[Dosimetric analysis of different optimization algorithms for three-dimensional brachytherapy for gynecologic tumors]

OBJECTIVE

To investigate the dosimetric difference between manual and inverse optimization in 3-dimensional (3D) brachytherapy for gynecologic tumors.

METHODS

This retrospective study was conducted among a total of 110 patients with gynecologic tumors undergoing intracavitary combined with interstitial brachytherapy or interstitial brachytherapy. Based on the original images, the brachytherapy plans were optimized for each patient using Gro, IPSA1, IPSA2 (with increased volumetric dose limits on the basis of IPSA1) and HIPO algorithms. The dose-volume histogram (DVH) parameters of the clinical target volume (CTV) including V200, V150, V100, D90, D98 and CI, and the dosimetric parameters D2cc, D1cc, and D0.1cc for the bladder, rectum, and sigmoid colon were compared among the 4 plans.

RESULTS

Among the 4 plans, Gro optimization took the longest time, followed by HIPO, IPSA2 and IPSA1 optimization. The mean D90, D98, and V100 of HIPO plans were significantly higher than those of Gro and IPSA plans, and D90 and V100 of IPSA1, IPSA2 and HIPO plans were higher than those of Gro plans (P < 0.05), but the CI of the 4 plans were similar (P > 0.05). For the organs at risk (OARs), the HIPO plan had the lowest D2cc of the bladder and rectum; the bladder absorbed dose of Gro plans were significantly greater than those of IPSA1 and HIPO (P < 0.05). The D2cc and D1cc of the rectum in IPSA1, IPSA2 and HIPO plans were better than Gro (P < 0.05). The D2cc and D1cc of the sigmoid colon did not differ significantly among the 4 plans.

CONCLUSION

Among the 4 algorithms, the HIPO algorithm can better improve dose coverage of the target and lower the radiation dose of the OARs, and is thus recommended for the initial plan optimization. Clinically, the combination of manual optimization can achieve more individualized dose distribution of the plan.

Versatile Triblock Peptide Self-Assembly System to Mimic Collagen Structure and Function

The construction of collagen mimetic peptides has been a hot topic in tissue engineering due to their attractive advantages, such as virus-free nature and low immunogenicity. However, all of the reported self-assembled peptides rely on the inclusion of risky elements of potential safety concerns or lack the capability of incorporating critical functional motifs. A versatile self-assembly design of pure synthetic peptides that can mimic the collagen structure and function remains an insurmountably challenging target. We have herein created a type of triblock peptide consisting of a central triple helical block and N-terminal/C-terminal blocks with oppositely charged amino acids. Favorable electrostatic interactions between the two terminal blocks have been demonstrated to trigger the triblock peptides to form collagen-like nanofibers with a distinct D-banding pattern. A length of 3 or above charged amino acid pairs as well as the maintenance of the triple helical conformation are required for the self-assembly of triblock peptides. Notably, integrin and discoidin domain receptor (DDR) binding sequences GFOGER and GVMGFO have been well demonstrated as vivid examples of convenient incorporation of functional motifs into the triblock peptides without interfering with their self-assembly. These triblock peptides provide a robust and versatile strategy to create next-generation peptide-based biomaterials that can recapitulate the structure and function of collagen, which have promising applications in the fields of tissue engineering and regenerative medicine.

THIRD bedside ultrasound protocol for rapid diagnosis of undifferentiated shock: a prospective observational study

INTRODUCTION

It is clinically challenging to differentiate the pathophysiological types of shock in emergency situations. Here, we evaluated the ability of a novel bedside ultrasound protocol (Tamponade/tension pneumothorax, Heart, Inferior vena cava, Respiratory system, Deep venous thrombosis/aorta dissection [THIRD]) to predict types of shock in the emergency department.

METHODS

An emergency physician performed the THIRD protocol on all patients with shock who were admitted to the emergency department. All patients were closely followed to determine their final clinical diagnoses. The kappa index, sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the initial diagnostic impression provided by the THIRD protocol, compared with each patient's final diagnosis.

RESULTS

In total, 112 patients were enrolled in this study. The kappa index between initial impression and final diagnosis was 0.81 (95% confidence interval=0.73-0.89; P<0.001). For hypovolaemic, cardiogenic, distributive, and obstructive types of shock, the sensitivities of the THIRD protocol were 100%, 100%, 93%, and 100%, respectively; the sensitivity for a 'mixed' shock aetiology was 86%. The negative predictive value of the THIRD protocol for all five types of shock was ≥96%.

CONCLUSION

Initial diagnostic judgements determined using the THIRD protocol showed favourable agreement with the final diagnosis in patients who presented with undifferentiated shock. The THIRD protocol has great potential for use as a bedside approach that can guide the rapid management of undifferentiated shock in emergency settings, particularly for patients with obstructive, hypovolaemic, or cardiogenic shock.

Diagnostic magnetic resonance imaging in synovial chondromatosis of the temporomandibular joint

The aim of this paper was to investigate the clinical and magnetic resonance imaging (MRI) features of synovial chondromatosis (SC) of the temporomandibular joint (TMJ). Fourteen patients with SC of the TMJ were included in the study. Clinical and MRI features were analysed and divided into three types based on MRI classification: type I with loose bodies, type II with homogeneous masses, and type III with a mixture of loose bodies and homogeneous masses. All SCs occurred in the superior compartment of the TMJ. There were two patients (14%) categorised as type I, five (36%) as type II and seven (50%) as type III. Four patients (29%) had disc perforation, and nine had bone erosion; among those nine, seven (78%) had type III and two (22%) type II. Histological examination showed inflammation and calcification in the synovial membrane and, and cartilage of the hyaline type in all cases. MRI has advantages in the diagnosis of SC.

Vitamin D does not improve lung function decline in COPD: a meta-analysis

OBJECTIVE

Vitamin D deficiency plays an important role in chronic obstructive pulmonary disease (COPD). However, the effects of vitamin D supplementation on lung function decline in COPD were inconsistently reported and a meta-analysis is thus needed.

MATERIALS AND METHODS

Eligible cohort and randomized controlled trials (RCTs) were searched from databases including PubMed, Embase, and Web of Science. Pooled standardized mean difference (SMD) with 95% confidence interval (CI) was calculated in a random or fixed effects model.

RESULTS

Eight studies reaching the inclusion criteria and involving 687 COPD patients were included. Pooled effect size showed vitamin D treatment resulted in no significant improvements in FEV1 (SMD: 0.38, 95% CI: -0.13 to 0.88, p= 0.144), FVC (SMD: 0.55, 95% CI: -0.49 to 1.58, p=0.299), and FEV1/FVC (SMD: 0.00, 95% CI: -0.27-0.27, p=0.995) in COPD patients. Subgroup analysis revealed neither short-term (<6 months) (SMD: 0.10, 95% CI: -0.17 to 0.37, p=0.479) nor long-term (≥6 months) (SMD: 0.52, 95% CI: -0.23 to 1.27, p=0.172) vitamin D exposure could significantly benefit lung function decline in COPD.

CONCLUSIONS

This meta-analysis shows neither short-term nor long-term additional supplementation of vitamin D can benefit the lung function decline in COPD. Moreover, large scale RCTs focusing on COPD smokers with low level of vitamin D should be considered.

[Trend in proportion and clinicopathological characteristics of young women with stage Ⅰa2 to Ⅱa2 cervical cancer]

Objective: To analyze the 13 years trend in proportion, risks factors and clinicopathological characteristics of young women with stage Ⅰa2 to Ⅱa2 cervical cancer by using multi-center data of cervical cancer in China. Methods: The clinicopathological data of 46 313 patients with cervical cancer treated from 37 hospitals in China were obtained from January 2004 to December 2016. Using clinical and pathologic data, each patient's stage was reclassified by the 2018 International Federation of Gynecology and Obstetrics (FIGO) staging system. A total of 19 041 patients were selected according to the following criteria: FIGO stage Ⅰa2 to Ⅱa2, underwent type B or C radical hysterectomy and pelvic lymphadenectomy. All the patients were divided into two groups: the study group of 1 888 patients aged 35 years or younger and the control group of 17 153 patients aged over 35 years. The 13 years trend in proportion of young women with stage Ⅰa2 to Ⅱa2 cervical cancer, risks factors and clinicopathological characteristics of two groups were retrospectively analyzed. Results: (1) The total number of hospitalized patients with stage Ⅰa2 to Ⅱa2 cervical cancer increased annually. However, a downward trend of patients aged 35 years or younger was observed (P<0.01) . The constituent ratio of patients aged 35 years or younger was significantly greater during 2004-2010 than that during 2011-2016 [12.6% (820/6 484) and 8.5% (1 068/12 557) , respectively; χ(2)=82.101, P<0.01]. (2) Compared with patients aged over 35 years, patients aged 35 years or younger had an earlier age at menarche, a later age at marriage, lesser gravida and parity (all P<0.01). The positive rate of high-risk HPV infection was not statistically different between two groups (all P>0.05). (3) The proportions of stage Ⅰ, exophytic type and non-squamous histological type in patients aged 35 years or younger were clearly higher than those in patients aged over 35 years (83.4% vs 68.5%, P<0.01; 63.2% vs 56.2%, P<0.01; 13.9% vs 12.0%, P<0.05, respectively). Whereas the poor differentiation ratios of the two groups had no statistical significance (P>0.05). (4) As for the postoperative pathological risk factors, the rate of surgical margin involvement in patients aged 35 years or younger was lower than that aged over 35 years (1.1% vs 1.8%, P<0.05), and the rate of depth of stromal invasion >1/2 in patients aged 35 years or younger was lower than that in patients aged over 35 years (40.1% vs 50.9%, P<0.01). In addition, there were no significant difference in parametrial margin involvement, tumor size and lymph vascular space invasion between two groups (all P>0.05). Conclusions: The trend in proportion among hospitalized patients for stage Ⅰa2 to Ⅱa2 cervical cancer in young women is decreasing yearly. Compared with cervical cancer in middle-aged and elderly women, cervical cancer in young women have an earlier age at menarche, a higher proportion of stage Ⅰ patients and non-squamous histological type. In terms of the postoperative pathological risk factors, the rate of surgical margin involvement and depth of stromal invasion >1/2 in young women with cervical cancer are lower than in middle-aged and elderly women.

Laparoscopic extraperitoneal uterine suspension with suture line instead of mesh

OBJECTIVE

To compare the safety and effectiveness of two different materials (mesh and suture line) used in laparoscopic extraperitoneal uterine suspension.

DESIGN

A retrospective observational study.

SETTING

Gynaecology departments in two hospitals in China.

POPULATION

Women with symptomatic pelvic organ prolapse (POP) of stage II or higher.

METHODS

The women were divided into two groups according to the two different materials for laparoscopic extraperitoneal uterine suspension: mesh or suture line. The baseline characteristics, perioperative details, complications, objective and subjective indexes of the two groups were compared.

MAIN OUTCOME MEASURES

The primary outcome was subjective satisfaction rate based upon validated questionnaires. The secondary outcome was objective anatomic assessment with the POP-Q system.

RESULTS

No difference was found in baseline characteristics and perioperative details except that there were more cases of cardiovascular disease (CVD) and associated other surgeries in the Line than the Mesh group (36 versus 19, P < 0.05; 12 versus 2, P < 0.05). Statistically significant improvements were found in anatomical measures of points Aa, Ba, Ap, Bp, C and TVL (P < 0.01), as well as functional and quality-of-life measures (P < 0.01 for PFDI-20 and PFIQ-7) between both groups. The postoperative PFDI-20, PFIQ-7 and PGI-I scores were not different between two groups (P > 0.05). Two cases of deep wound infection were observed in Mesh group at 3-month follow up.

CONCLUSIONS

Laparoscopic extraperitoneal linear uterine suspension is easy to perform and is associated with fewer mesh-related complications. It is more secure, especially in elderly women and in those with physical complications.

TWEETABLE ABSTRACT

Laparoscopic extraperitoneal linear uterine suspension is safe, with fewer mesh-related complications.

Deciphering the spectrum of somatic mutations in the entire mitochondrial DNA genome

The mitochondrion is a crucial intracellular organelle responsible for regulating cellular energy metabolism, producing free radicals, initiating and executing the apoptotic pathways. Previous studies have shown that somatic mutations in mitochondrial DNA are associated with various tumors, which may be involved during carcinogenesis and tumor progression. To examine the mutation pattern in cancer, 625 reported somatic mutations in the mitochondrial DNA genome were analyzed. We found that, except for deletions and insertions, most somatic mutations were point mutations, accounting for 89.44% of somatic mutations. Transition was the predominant form of somatic mutation in the entire mitochondrial DNA genome, accounting for 87.12% of point mutations, most of which were homoplastic. Frequency statistics analysis of point mutations indicated that, except for 3 tRNA genes, the mutations were distributed on all resting genes and in the D-loop region, with the latter showing the highest frequency of somatic mutation (19.34%), followed by the tRNA leucine 2 gene and non-coding regions between base pairs 5892 and 5903, while 13 coding-region genes and 2 rRNA genes showed a relatively lower frequency of somatic point mutations. Nonsynonymous mutations and terminal amino acid changes were the primary point somatic mutations detected from 13 coding-region genes, which may cause mitochondrial dysfunction in cancer cells. We found that the somatic mutations may affect the mitochondrial DNA genome; the non-coding region should be examined to identify somatic mutations as potential diagnostic biomarkers for early detection of cancer.

Establishment of reference panel for human platelet antigen genotyping

BACKGROUND AND OBJECTIVES

Human platelet antigens (HPAs) are platelet-specific alloantigens associated with polymorphisms of platelet surface glycoproteins (GPs), and they can induce alloantibodies when individuals lacking a particular polymorphism are exposed to them via pregnancy or transfusion. Immune responses to HPAs are involved in the pathogenesis of several clinical syndromes. HPA genotyping is therefore important for clinical diagnosis and laboratory research. This study aims to establish a reference panel for HPA genotyping.

MATERIALS AND METHODS

Genomic DNA extracted from human blood was used as the template for amplifying HPA (1a-5a and 15a) gene fragments using specific primers. The amplified products were cloned into pGM-T vectors, which were transformed into competent TOP10 cells. After clone screening and amplification, the plasmids were extracted and sequenced. Next, the gene fragments HPA-1b-5b and 15b were obtained by site-directed mutagenesis using the corresponding HPA-1a-5a and 15a plasmids as template DNA.

RESULTS

We successfully constructed reference plasmids for HPA genotyping with HPA-1a-5a, 15a, HPA-1b-5b and 15b. The DNA sequences were consistent with those published in GenBank.

CONCLUSION

Obtaining reference DNA for low-frequency HPAs is very difficult, and the successful construction of reference plasmids for the six HPA systems may solve this problem. Establishment of this panel has laid the foundation for future research on HPA genotyping.

Few-layer graphene direct deposition on Ni and Cu foil by cold-wall chemical vapor deposition

We report an alternative synthesis process, cold-wall thermal chemical vapor deposition (CVD), is replied to directly deposit single-layer and few-layer graphene films on Ar plasma treated Ni and Cu foils using CH4 as carbon source. Through optimizing the process parameters, large scale single-layer graphene grown on Ni foil is comparable to that grown on Cu foil. The graphene films were able to be transferred to other substrates such as SiO2/Si, flexible transparent PET and verified by optical microscopy, Raman microscopy and scanning electron microscopy. The sheet resistance and transmission of the transferred graphene films on PET substrate were also discussed.

Combination of valproic acid and ATRA restores RARβ2 expression and induces differentiation in cervical cancer through the PI3K/Akt pathway

Epigenetic silencing of the tumor suppressor gene, RARβ2, through histone deacetylation has been established as an important process of cervical carcinogenesis. This pivotal role has led to the suggestion that a combination of retinoids selective for RARβ2 with histone deacetylase (HDAC) inhibitors may have therapeutic potential. Valproic acid (VPA), a HDAC inhibitor, has a critical role in the regulation of gene expression through histone acetylation and causes transformed cells to undergo growth arrest, differentiation, and apoptosis. Therefore, we hypothesized that the combination of VPA and ATRA could restore RARβ2 expression, thus resulting in enhanced anti-neoplastic activity in cervical cancer. Here, we show that VPA combined with ATRA led to hyperacetylation of histone H3 and a significant alteration of gene expression in cervical cancer cells, including RARβ2 gene expression, which was upregulated 50- to 90-fold. The combination therapy effectively inhibited the growth of cervical cancer cells more than the single agent treatment both in vitro and in vivo. The additive effects were associated with a significant upregulation of p21(CIP1) and p53 as well as a pronounced decrease in p-Stat3. Furthermore, the combined treatment led to cell cycle arrest predominantly at the G1 phase, and it preferentially induced cell differentiation rather than apoptosis in cervical cancer cells. The differentiation program was determined by the presence of E-cadherinmediated adhesion and activation of the PI3K/Akt pathway. Taken together, these results provide new insight into the mechanisms of enhanced antitumor activity of the HDAC inhibitor and ATRA regimen, thus offering a new therapeutic strategy for cervical cancer patients.

One-dimensional single-crystalline bismuth oxide micro/nanoribbons: morphology-controlled synthesis and luminescent properties

Based on a facile vapor-phase transport method without any catalyst and template, one-dimensional single-crystalline bismuth oxide (Bi2O3) micro/nanoribbons were fabricated on silicon substrates in large quantities and morphology-controlled fabrication of Bi2O3 was achieved from a single precursor. The widths of Bi2O3 ribbons varied from 0.2 to 20 microm depending on the deposition temperatures. The thickness was in the range of 0.1-2 microm and the length reached several hundred micrometers and even millimeter range. The detailed composition and structural analysis confirmed the single-crystalline nature of alpha-Bi2O3 micro/nanoribbons with monoclinic structure. The photoluminescence spectrum of a single Bi2O3 ribbon showed a broadband emission from 450 to 750 nm in the visible region, consisting two peaks located at 589 and 697 nm which were primarily originated from the impurity ions and crystal defects. A self-catalyzed vapor-solid model was proposed to account for the growth mechanism of Bi2O3 ribbons with different morphologies.

Extra-articular diffuse tenosynovial giant cell tumour of the infratemporal fossa: report of a case and literature review

The authors describe a 34-year-old man who presented with an unapparent swelling on the right preauricular zygomatic region, with progressive limitation of mouth opening and slight temporomandibular joint pain. Based on fine-needle aspiration cytology and radiological investigations, the patient was diagnosed preoperatively as having a possible tenosynovial giant cell tumour (TGCT). Surgical treatment was effective and no local recurrence was observed. Histological and immunohistochemical examination diagnosed an extra-articular diffuse TGCT. The clinical features, histopathological characteristics, imaging modalities, diagnostic methods and treatment of TGCT are discussed and a review of the relevant literature is presented.

Effect of conditioned medium of mesenchymal stem cells on the in vitro maturation and subsequent development of mouse oocyte

Mesenchymal stem cells (MSCs) secrete a variety of cytokines and growth factors in addition to self-renewal and multiple forms of differentiation. Some of these secreted bioactive factors could improve meiotic maturation in vitro and subsequent embryo developmental potential. The aim of the present study was to determine whether in vitro maturation (IVM) of mouse oocyte with or without cumulus cells could be improved by contact with conditioned medium (CM) of MSCs as well as the efficiency of CM to support follicular growth and oocyte maturation in the ovarian organ of mice cultured on soft agar. The developmental potential of matured oocyte was assessed by blastocyst formation after in vitro fertilization (IVF). Germinal vesicle stage oocytes with or without cumulus cells were subjected to IVM in either CM, Dulbecco's modified Eagle's medium (DMEM), alpha-minimum essential medium (alpha-MEM) or human tubal fluid (HTF). Approximately 120 oocytes were studied for each medium. CM produced a higher maturation rate (91.2%) than DMEM (54.7%), alpha-MEM (63.5%) and HTF (27.1%). Moreover, CM improved embryo development to blastocyst stage significantly more than DMEM and HTF (85 vs 7% and 41.7%, respectively) but there was no significant difference compared with alpha-MEM (85 vs 80.3%). The behavior of cortical granules of IVM oocytes cultured in CM revealed cytoplasmic maturation. Moreover, CM also supported preantral follicles growth well in organotypic culture on soft agar resulting in the maturation of 60% of them to developmentally competent oocytes. The production of estrogen progressively increased approximately 1-fold every other day during organ culture, while a dramatic 10-fold increase in progesterone was observed 17 h after human chorionic gonadotropin stimulus at the end of culture. Thus, CM is an effective medium for preantral follicle growth, oocyte maturation, and sequential embryo development.

A study on pathogenesis of sudden death syndrome in broiler chickens

Sudden death syndrome (SDS) in fast growing broiler chickens has been recognized as a patho-physiological entity for four decades, but its pathogenesis still remains unknown. More recent investigations provided evidence that link SDS to cardiac arrhythmia, but the mechanism triggering arrhythmogenesis and factors responsible for fatal outcome are poorly understood. In order to understand the chain of events leading to SDS in broilers, the present study focused on putative mechanisms that trigger arrhythmia and mechanisms that predispose the myocardium to fatal arrhythmia. Susceptibility of broilers to cardiac arrhythmia under stress conditions was evaluated using a simulated stress test with epinephrine. Detailed histopathological evaluation of the broiler heart was undertaken to identify structural features that may predispose the myocardium to fatal arrhythmia. The simulated stress challenge revealed that many broilers are highly susceptible to stress induced cardiac arrhythmia. In some broilers the stress challenge induced severe ventricular arrhythmia, and the life threatening nature of this arrhythmia was evidenced by the fact that several birds showing the most severe arrhythmic responses, died suddenly within several days after the stress challenge. Examination of hearts of broilers that died of SDS revealed microscopic lesions in the cardiomyocytes, and widespread changes in the sub-endocardial and mural His-Purkinje system (HPS). Immune staining for Caspase-3 confirmed that numerous Purkinje cells in the left ventricular myocardium from broiler chickens that died of SDS were undergoing apoptosis. The observed lesions suggest that the electrical stability of the myocardium was compromised. Taken together, our findings indicate that stress is a most likely trigger of cardiac arrhythmia in broilers, whereas the pathological changes seen in the myocardium and in the HPS in fast growing broilers provide a very conducive milieu for sustained ventricular arrhythmia. In cases where the electrical stability of the myocardium is compromised, even an episodic arrhythmic event may readily degenerate to catastrophic ventricular fibrillation and sudden death. We conclude that the combination of stress and changes in the cardiomyocytes and HPS are the key requisite features in the pathogenesis of SDS.

Biochemical factors limiting myocardial energy in a chicken genotype selected for rapid growth

Broiler chickens (Gallus gallus) genetically selected for rapid growth are inherently predisposed to heart failure. In order to understand the biochemical mechanisms associated with the deterioration of heart function and development of congestive heart failure (CHF) in fast-growing chickens, this study examined several factors critical for myocardial energy metabolism. Measured variables included cardiac energy substrates [creatine phosphate (CrP), adenosine triphosphate (ATP), l-carnitine], activity of selected cytosolic enzymes [creatine kinase (CK; EC 2.7.3.2), lactate dehydrogenase (LDH; EC 1.1.1.27)] and mitochondrial enzymes [pyruvate dehydrogenase (PDH; EC 1.2.4.1), alpha-ketoglutarate dehydrogenase (alpha-KGDH; EC 1.2.4.2)]. The CK activities were higher in fast-growing and CHF broilers as compared to slow-growing broilers (p<0.05). Cardiac LDH and alpha-KGDH activities were not changed (p>0.05), whereas PDH activity was highest (p<0.05) in broilers with CHF. Deterioration of heart function is correlated with lowered cardiac ATP, CrP, and l-carnitine levels (all p<0.05). Depletion of high energy phosphate substrates, ATP and CrP, is evident in fast-growing chickens and those that developed CHF. Increased activity of CK suggests that cardiac energy management in fast-growing broilers and those with CHF largely depends on contribution of this pathway to regeneration of ATP from CrP. In this scenario, inadequate level of CrP is a direct cause of ATP insufficiency, whereas low cardiac l-carnitine, because of its role in fatty acid transport, is most likely an important factor contributing to shortage of key substrate required for synthesis of cardiac ATP. The insufficiencies in cardiac energy substrate synthesis provide metabolic basis of myocardial dysfunction in chickens predisposed to heart failure.

Darbepoetin alfa administered once monthly maintains hemoglobin concentrations in patients with chronic kidney disease

BACKGROUND

Darbepoetin alfa is an erythropoiesis-stimulating glycoprotein that functions by the same mechanism as recombinant human erythropoietin (rHuEPO), but has a three-fold longer serum half-life. Reduction in the frequency of darbepoetin alfa administration would be beneficial to patients with renal disease and their healthcare providers. This study evaluated the effect of extending the darbepoetin alfa dosing interval to once monthly in patients with chronic kidney disease (CKD) not receiving dialysis.

METHODS

This study was a multicenter, open-label study of 97 patients with CKD not on dialysis. Patients receiving stable subcutaneous doses of darbepoetin alfa once every two weeks were converted to darbepoetin alfa once monthly for 29 weeks. The proportion of patients who successfully maintained hemoglobin concentrations between 10.0 and 12.0 g/dl and the mean darbepoetin alfa dose were evaluated. Safety measurements (e.g. adverse events, laboratory parameters, blood pressure) and seroreactivity were assessed.

RESULTS

Hemoglobin concentration was maintained within the target range in 79% (95% confidence interval (CI) = 71% to 87%) of all patients receiving darbepoetin alfa and in 85% (95% Cl = 78% - 93%) of patients who completed the study period. The mean +/- standard deviation monthly darbepoetin alfa dose was similar between baseline (88.7 +/- 49.9 microg) and the evaluation period (86.6 +/- 78.8 microg). The safety profile for monthly darbepoetin alfa administration was comparable with that previously observed with more-frequent administration.

CONCLUSION

Patients with CKD who are clinically stable on darbepoetin alfa administered once every two weeks can be safely and effectively converted to darbepoetin alfa administered once monthly.

Longitudinal follow up of SIVmac pathogenesis in rhesus macaques of Chinese origin: emergence of B cell lymphoma

Two subspecies of rhesus (Rh) macaques, the Chinese (Ch) and Indian (Ind) subspecies were infected intravenously with 100TCID50 SIVmac239. CD4+, CD8+ T cells, plasma viral loads, depletion of intestinal lymphocytes with memory phenotype, humoral immune responses and clinical courses were monitored for 600 days. The pathogenesis of SIVmac was also compared with primary human immunodeficiency virus (HIV) infection of humans. Plasma viral loads in Ch Rh were lower in the acute and chronic phases compared with Ind Rh. SIVmac pathogenesis in Ch Rh was closer to virus loads in untreated HIV infected humans. Ch Rh had higher CD4/CD8 ratios, stronger antibody responses and interestingly, less depletion of intestinal memory CCR5+ CD4+ T lymphocytes compared with Ind Rh. One Ch Rh developed B cell origin lymphoma at 570 days post-infection, the first such report in this subspecies. Three of four Ind Rh developed AIDS within 6 months. The findings indicate that Ch Rh are more resistant to SIVmac pathogenesis compared with Ind Rh and that Ch Rh paralleled HIV-1 infections in untreated adult humans. The SIVmac infected Ch Rh subspecies are an acceptable model for HIV/AIDS.

[A pilot study on arsenic removal facilities for central supply of drinking water]

In order to promote the application and industrialization of an arsenic removal agent developed in this project, and to improve the technology, it is necessary to have a median sized facility to test the effects, capacity and regeneration of the agent. A facility with the capacity of 1 m3/h for arsenic removal was installed in a bottled water plant, which has been operated since April 1999. The results showed that the arsenic content of effluent water has met the requirement of the national standard for drinking water. The effect of arsenic removal was by 2 mg/g. The annual cost per person was only 1.46 Yuan RMB. The operation and maintenance of the facility was simple and no need to adjust the pH of influents and effluents. The chemical regenerative agent was safe, low cost and effective. Therefore, the facility can be used in rural areas and the water plants while the arsenic in source water was higher than 0.05 mg/L.

[Study on an enhancing agent for removing arsenic from drinking water]

Drinking water contaminated by arsenic for an extended period of time could be detrimental to the health of people. Some preliminary symptoms could be alleviated by drinking water non-contaminated. It is important to develop an arsenic removal agent with a specific property of most efficient, cost-effective and easy for operation. The results showed that the capacity of the agent developed in this study was 10 times higher for arsenic removal than other agent available. The lowest arsenic content of the treated water was 0.05 mg/L. The special function of this agent was arsenic removing without changing other components and the concentrations of other elements in the treated water. The operation and management was simple without adjusting pH of the influent and effluent water. The agent was 5 times cheaper in cost than alumina or activated carbon, because it was a reusable oxidation-catalyst. Therefore, the agent could be widely applied in drinking water plants or used as a purifier at home in the high arsenic areas.

[Determination of lead in whole blood by graphite furnace atomic absorption spectrometry with matrix modifier and L'vov platform]

Lead in whole blood has been determined by graphite furnace atomic absorption spectrometry with matrix modifier and L'vov platform. It's found that addition of the mixture solution of 0.6% NH4H2PO4 and 0.4% NH4NO3 as matrix modifier, the ash temperature will increase up to 900 degrees C. 750 degrees C is practically used for ash temperature. D2 lamp is used for background correction. Lead in whole blood was directly determined after addition of 0.3% Triton X-100 without digestion. The analytical results of six whole samples is satisfactory. The recoveries are 93%-106%. The relative standard deviations are 3%-7%. The sensitivity of characteristic mass is 6.0 pg/1%.

[Disinfection for cistern water]

Rainwater is often collected into cisterns (pits or tanks) for household using as drinking water source in the rural areas of the northwest and the southeast coast in China, where no enough fresh water resource is available. However, the total number of bacteria and coliforms in the cisterns water was higher than the standard of that in drinking water. In order to ensure the safety for drinking, the effectiveness, conditions of treatment and cost for such disinfection methods compared with solar radiation, ultraviolet (UV), chloridation, micro-filteration and KDF were studied in 10 households in Cixi of Zhejiang Province and Weiyuan of Gansu Provinces, respectively. The micro-filteration is more compatible for bacteria removal in the tanks, while chloridation more for disinfection in the underground pits.

[Analysis of hepatitis G virus genotypes in some areas of China]

OBJECTIVE

To study the genotype distribution of hepatitis G virus (HGV) isolated from different population in some areas of China.

METHODS

A total of 12 strains of HGV were isolated from different areas of China (three from Guangxi Zhuang Autonomous Region, three from Hebei Province, one from Heilongjiang, Jiangxi, Guangdong, Jiangsu, Anhui, Jilin Provinces and Xinjiang Autonomous Region each). The HGV 5' untranslated region (UTR) of the 12 isolates was sequenced and compared with other 26 isolates previously reported (17 from China and nine from other countries).

RESULTS

The nucleotide sequences of five HGV clones isolated from the same patient with HGV infection were identical, with the homology of 99.1% - 100%, indicating that variation of HGV in the same human body was very limited. Genotyping could be based on the sequence of one positive clone isolated from a patient with HGV infection. The homology of the nucleotide sequences in the 12 isolates was 96.8% - 99.4%, suggesting that they belonged to the same genotype. The homology of the 12 isolates was 88.0% - 89.7%, 87.2% - 90.3% and 94.7% - 96.3%, respectively, as compared with HGV genotypes 1 (U36380), 2 (U44402) and 3 (D90601), which indicated that all the 12 HGV isolates belonged to genotype 3. Phylogenetic distance analysis of the 38 isolates suggested that HGV strains isolated from China could be further divided into different subgroups.

CONCLUSION

The majority of Chinese HGV isolates belonged to genotype 3 and they could be further divided into different subgroups.

Health impairments arising from drinking water polluted with domestic sewage and excreta in China

Raw water of poor quality still causes many drinking-water associated health problems all over China, largely because of poor sanitation, inadequate disposal of sewage and excreta. Eutrophication due to excess of total nitrogen and phosphorous in some sources for drinking-water has led to massive proliferation of cyanobacteria. The dominant species of cyanophyta can produce microcystins, a potent liver cancer promotor. As in previous studies, high incidence of liver cancer coincided with high microcystin concentration in the source water, especially in pond water. A frequent consequence of heavy pollution of source water is further the high incidence of infectious intestinal diseases, which are more than 10-100 times as frequent in China than in developed countries.

[Toxic effect of fluoride-arsenic on the reproduction and development of rats]

To determine the effects of the fluoride-arsenic exposure on the reproductive function and the development of offspring. Two generations-one nest reproduction was studied in Wistar rats to assess the changes of reproductive function and structure of ovary and development of their offspring after rats were exposed to different doses of fluoride(NaF)-arsenic(As2O3) orally. The rates of the pregnancy, normal parturition, survival and feeding survival in high dose group were lower than that in low dose groups and control. The rates of pregnancy were 73.08% and 61.54% in high dose groups, and 92.31% and 84.62% in the control. But the contents of fluoride and arsenic in rats' offspring were increased. The weights of rats' offspring in high dose group were lighter than that in control. The average weights were 38.45 g in high dose group and 60.84 g in control one month after birth. Pathological changes could be found in each stage of oocytes with transmission electron microscope(TEM). Conclusion Fluoride-arsenic exposure has adverse effects on the reproductive system and the development of rats' offspring.

Epidermal growth factor receptor expression in neurofibromatosis type 1-related tumors and NF1 animal models

We have found that EGF-R expression is associated with the development of the Schwann cell-derived tumors characteristic of neurofibromatosis type 1 (NF1) and in animal models of this disease. This is surprising, because Schwann cells normally lack EGF-R and respond to ligands other than EGF. Nevertheless, immunoblotting, Northern analysis, and immunohistochemistry revealed that each of 3 malignant peripheral nerve sheath tumor (MPNST) cell lines from NF1 patients expressed the EGF-R, as did 7 of 7 other primary MPNSTs, a non-NF1 MPNST cell line, and the S100(+) cells from each of 9 benign neurofibromas. Furthermore, transformed derivatives of Schwann cells from NF1(-/-) mouse embryos also expressed the EGF-R. All of the cells or cell lines expressing EGF-R responded to EGF by activation of downstream signaling pathways. Thus, EGF-R expression may play an important role in NF1 tumorigenesis and Schwann cell transformation. Consistent with this hypothesis, growth of NF1 MPNST lines and the transformed NF1(-/-) mouse embryo Schwann cells was greatly stimulated by EGF in vitro and could be blocked by agents that antagonize EGF-R function.

[The effect of fluoride-arsenic exposure on the lipid peroxidation and antioxidation of the offspring of rats]

OBJECTIVE

To provide information on the effects of the offspring of rats exposed to fluoride-arsenic.

METHODS

The levels of lipid peroxidation and the abilities of antioxidation were determined in the blood of the rats and their offsprings under two generations-one nest reproductive test.

RESULTS

The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the blood decreased with the increase of exposure dose. For example, the activity of SOD, was 14.56, 13.74, 11.89 and 11.21 micromol x min(-1) x mg Hb(-1) in different dose groups of F(2), respectively. In contrast, the concentration of lipid peroxides (LPO) increased. Eight weeks after exposure, the activities of SOD and GSH-Px increased, the activity of SOD was 13.97, 13.55, 13.47 and 12.76 micromol x min(-1) x mg Hb(-1), respectively, and the concentration of LPO returned to normal level.

CONCLUSION

Fluoride-arsenic exposure can cause oxidative damage of the rat's offspring.

[Effect of fluoride-arsenic exposure on the neurobehavioral development of rats offspring]

In order to explain the effects of fluoride-arsenic exposure on the neurobehavioral development of rats, a two generations-one nest reproductive test was used. Wistar rats were exposed to fluoride and arsenic for two generations. The results demonstrated that: with the increasing concentrations of fluoride and arsenic, the positive rates of early physiological development and nerve reflex were decreased obviously, and the abilities of learning and memory of the offspring were decreased, the swimming and enduring anoxia time gradually shortened. The pathological changes of brain under electron microscope were as follows: decreased number of nerve cells, irregular cell nucleus, organellae degeneration, and obvious decreased number of synapses. It was demonstrated that fluoride-arsenic displayed distinct damage on the nerve system of the offspring.

Neurofibromin, the neurofibromatosis type 1 Ras-GAP, is required for appropriate P0 expression and myelination

The neurofibromatosis type 1 (NF1) gene product, neurofibromin, regulates activation of the Ras intracellular signaling pathway in Schwann cells. Schwann cells purified from mouse embryos with null mutations in the Nf1 gene increase expression of the major myelin glycoprotein P0. v-Ras expression in cultured Schwann cells partially mimics loss of Nf1, suggesting a role for Ras in upregulation of P0 expression in Nf1-deficient cells. We tested whether loss of Nf1 alters the ability of Schwann cells to form myelin. No significant changes in myelin formation resulted when Nf1-deficient or v-Ras-expressing Schwann cells were cultured with normal neurons. Yet, in organotypic cultures of neurons, Schwann cells, and fibroblasts without neurofibromin, myelination was dramatically reduced. We suggest that Nf1-dependent signaling cascades in neurons and/or fibroblasts, as well as Schwann cells, are required for normal myelination.

[A cross-sectional study on HGV infection in a rural population]

OBJECTIVE

To determine the epidemiological characteristics and clinical significance of HGV infection, and to compare with HBV and HCV infections.

METHODS

Anti-HGV, HBsAg, anti-HBs, anti-HBc and anti-HCV were detected by enzyme-linked immunoassays (EIA). Anti-HGV positive sera were further tested for HGV RNA by a nested reverse transcription polymerase chain reaction (RT-nPCR).

RESULTS

The anti-HGV prevalence rate was 12.9%. It was relatively low in children under 10 years, and then increased with age and peaked in the group of 50-60 years of age (29.2%). The positive rate of HBsAg was 12.6%, and it quickly reached the highest (16.2%) in the 5-year old group. The prevalence rate of HBV infection was 64.9%, and increased to a high level in the group of 10 years of age, and maintained high up to 79.2% in the 50 years old group. The HCV infection rate was 15.3%. No anti-HCV positive cases were found in the group under 10 years of age. It was particularly high in the 20-40 years age group, and reached the peak in the group of 30 years old. No significant differences were found in the infection rates of HBV, HCV and HGV between male and female. HGV infection was associated with the history of blood donation, and the sexual transmission between couples. The anti-HGV positive rate of wives with anti-HGV positive husbands was 53.3%, significantly higher than that of those with anti-HGV negative husbands (7.8%). HGV coinfection with HBV or HCV had no influence on serum alanine aminotransferase (ALT). NO ALT elevation was found in the group with HGV infection alone.

CONCLUSIONS

The epidemiological characteristics of HGV infection are different from those of HBV and HCV. HGV is transmitted by blood and sex, and does not seem to cause liver damage.

Increased overall antibiotic susceptibility in Staphylococcus aureus femAB null mutants

The staphylococcal pentaglycine side chain of the peptidoglycan is reduced to one glycine in femAB null mutants. This is associated with increased susceptibility to methicillin and to a whole range of unrelated antibiotics as well. Genetic evidence suggests that femAB null mutants are only viable because of a compensatory mutation in an unlinked site.

[Accumulative arsenic level in viscera in offsprings of exposed parent rats]

OBJECTIVE

To explore the metabolism and accumulation of arsenic in the offsprings of exposed rats.

METHODS

Arsenic contents in viscera of the rat offsprings, whose parents exposed to different dose of arsenic, were determined with a two-generation reproductive test.

RESULTS

Arsenic contents in the heart, liver, brain, kidney and spleen of the offsprings correlated with the dose their exposed parents, the highest in the spleen. There was significant difference in arsenic contents of the viscera between two generations of rats. Arsenic contents in the viscera of the offsprings declined significantly one month after stopping exposure to arsenic, but still higher than that in controls.

CONCLUSION

It suggests that arsenic can deposit in the bodies of the rat offsprings, and excreted from the bodies slowly.

Schistosomiasis: the cleanup continues

During the past 40 years immense progress has been made in the control of schistosomiasis in China. The authors consider how the 100 million people in the country who are still at risk from the disease can be protected.

[The effect of arsenic on reproduction and offspring development of rats]

The effect of arsenic on reproduction and offspring development of Wistar rats was studied. The results demonstrated that the pregnant rate and feeding survival rate in high dose group were lower than these of in the groups of control and low dose. The differences of normal parturition rate and the survival rate in all the groups were not significant. The contents of arsenic in the young rats were increased by the doses of arsenic and the differences were significant. After 10, 20 and 30 days of birth, the weight of offspring in high dose group was lighter than that in the groups of control and low dose. According to the results, arsenic can affect the reproduction of rats and the development of their offspring.

Nf1-deficient mouse Schwann cells are angiogenic and invasive and can be induced to hyperproliferate: reversion of some phenotypes by an inhibitor of farnesyl protein transferase

We have developed a potential model of Schwann cell tumor formation in neurofibromatosis type 1 (NF1). We show that mouse Schwann cells heterozygous or null at Nf1 display angiogenic and invasive properties, mimicking the behavior of Schwann cells from human neurofibromas. Mutations at Nf1 are insufficient to promote Schwann cell hyperplasia. Here we show that Schwann cell hyperplasia can be induced by protein kinase A activation in mutant cells. Removal of serum from the culture medium also stimulates hyperplasia, but only in some mutant cells. After serum removal, clones of hyperproliferating Schwann cells lose contact with axons in vitro, develop growth factor-independent proliferation, and exhibit decreased expression of the cell differentiation marker P0 protein; hyperproliferating cells develop after a 1-week lag in Schwann cells heterozygous at Nf1. The experiments suggest that events subsequent to Nf1 mutations are required for development of Schwann cell hyperplasia. Finally, an anti-Ras farnesyl protein transferase inhibitor greatly diminished both clone formation and hyperproliferation of null mutant cells, but not invasion; farnesyl transferase inhibitors could be useful in treating benign manifestations of NF1.

[Health assessment on safe treatment of night-soil on schistosomiasis endemic areas]

The family size biogas tanks were built in the study site. Their effects were monitored. Faecal coliform and parasite eggs were examined before and after biogas digestion. The results of whole-year operation indicate that faecal coliform and parasite eggs can be reduced by 99.7% and 99.8%, respectively. The schistosome eggs survival experiment showed that the eggs all died off in 100 days of retention in biogas tanks. Therefore, the appropriate technology of nightsoil treatment can effectively interrupt the life cycle of schistosome.

[Determination of lead in blood by polarography]

A method for determination of trace lead in blood with complex catlysis polarography was develop. The peak potential of lead is -0.54 V in the system of hydrochloric acidpotassium iodide-vanadium (IV)-ethanol-ascorbic acid. There is good linelar relationship between peak current and lead concentration in the range of 0-1.0 microgram/3 ml. The recoveries of spiked samples ranged from 76.0% to 105.0% and the average recovery was 91.0% with RSD of 3.6% to 7.0%. The detection limit was 45 micrograms/L. The blood samples of 24 normal people and 6 workers with occupational exposure to lead were measured and the results were concordant with the clinical diagnoses. The proposed method is simple, rapid, sensitive and reliable. It is suitable for determination of trace lead in blood.