[Significance of induction chemotherapy in the treatment of locally advanced laryngeal cancer and hypopharyngeal cancer]

Objective:To explore the effect of induction chemotherapy on the treatment of locally advanced laryngeal cancer and hypopharyngeal cancer.Method: A retrospective analysis of 40 cases with advanced laryngeal cancer or hypopharyngeal cancer at the stage of Ⅲ-Ⅳb.Forty patients were randomly divided into two groups:treatment group(receive induction chemotherapy before surgery plus radiation therapy) and control group (receive surgery plus radiotherapy).During a five years followup, the therapeutic effect, the adverse treatment reactions, the survival rate and the larynx preservation rate were analyzed and compare between the two groups.Result:Twenty patients in the treatment group all received induction chemotherapy. After treatment, 3 patients with complete remission(CR), 14 patients with partial response(PR),2 patients in stable condition, and 1 patient with progression disease. The effective number of the treatment patients was 17 in the treatment group. The oneyear survival rate in the treatment group was higher than that in the control group(P<0.05),however, the 3-year and 5-year survival rate were similar in the two groups(P>0.05). The arynx preservation rate in the treatment and control group was 45%（9/20）and 15%（3/20）,respectively; and there was significant difference between the two groups(P<0.05).Conclusion:The Induction of chemotherapy has a better shortterm curative effect, which can alleviate clinical staging of the cancer, reduce tumor micro infiltration, increase the chance of patients with surgical opportunity and radiation therapy, and ultimately improve the outcome after treatment.

Genome-wide analysis of TCP family in tobacco

The TCP family is a transcription factor family, members of which are extensively involved in plant growth and development as well as in signal transduction in the response against many physiological and biochemical stimuli. In the present study, 61 TCP genes were identified in tobacco (Nicotiana tabacum) genome. Bioinformatic methods were employed for predicting and analyzing the gene structure, gene expression, phylogenetic analysis, and conserved domains of TCP proteins in tobacco. The 61 NtTCP genes were divided into three diverse groups, based on the division of TCP genes in tomato and Arabidopsis, and the results of the conserved domain and sequence analyses further confirmed the classification of the NtTCP genes. The expression pattern of NtTCP also demonstrated that majority of these genes play important roles in all the tissues, while some special genes exercise their functions only in specific tissues. In brief, the comprehensive and thorough study of the TCP family in other plants provides sufficient resources for studying the structure and functions of TCPs in tobacco.

[Endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus: a clinicopathologic analysis of 5 cases]

OBJECTIVE

Endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus is a rare morphological variant of endometrioid carcinoma. The biphasic morphological features may cause confusion with carcinosarcoma of the uterus, leading to misdiagnosis. The aim of this article is to elucidate the clinicopathological characteristics of such endometrial carcinoma to avoid misdiagnosis.

METHODS

The clinical and pathological data of 5 cases of endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus were collected and analyzed.

RESULTS

The age of the 5 patients ranged from 29 to 39 years, with a mean age of 33 years. Four patients underwent surgery of radical hysterectomy, the other dilation and curettage biopsy. Among the former, 3 patients were at FIGO stageⅠA, the other ⅢC1. Microscopically, all 5 tumors contained endometrioid carcinoma components, 4 of which were FIGO gradeⅠ, the remaining one was grade Ⅱ. Each tumor was of variable proportions of corded and hyalinized areas ranging from 10% to 60%. The cells in the corded and hyalinized areas were epithelioid, fusiform and spindle in morphology, admixed with the endometrioid carcinoma component, resulting in a biphasic pattern. The corded and hyalinized component exhibited distinctively different immunophenotypical feature from that by the conventional endometrioid carcinoma component. The results of follow-up for 4 patients of 7 to 68 months (mean=26.5 months) revealed that all patients were alive without recurrence of the malignancy.

CONCLUSIONS

Endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus presents unique morphology, and the patients are usually young with relatively favorable prognosis. The definite mechanism for the pathogenesis of the sex cord-like formations and hyalinization needs further investigation.

Preparation of N-doped activated carbons with high CO2 capture performance from microalgae (Chlorococcum sp.)

N-Doped activated carbons with high CO₂ adsorption capacity have been prepared from sugar-rich microalgae (Chlorococcum sp.) feedstock via simple hydrothermal carbonization coupled with KOH activation or NH₃ modification.

Genetic characterization of red-colored heartwood genotypes of Chinese fir using simple sequence repeat (SSR) markers

The present study investigated the genetic characterization of red-colored heartwood Chinese fir [Cunninghamia lanceolata (Lamb.) Hook.] in Guangxi using 21 simple sequence repeat (SSR) markers and analyzes of the genetic variation (N = 149) in samples obtained from five sites in Guangxi Province, China. The number of different alleles and the Shannon's information index per locus ranged from 3 to 12 and from 0.398 to 2.258 with average values of 6 and 1.211, respectively, indicating moderate levels of genetic diversity within this germplasm collection. The observed and expected heterozygosity ranged from 0.199 to 0.827 and from 0.198 to 0.878 with an average of 0.562 and 0.584, respectively. Although, the mean fixation index was 0.044, indicative of a low level of genetic differentiation among germplasms, analysis of molecular variance revealed considerable differentiation (99%) within the samples. The neighbor-joining dendrogram revealed that the majority of red-colored Chinese fir genotypes were apparently not associated with their geographic origins. Further analysis by STRUCTURE showed that this Guangxi germplasm collection could be divided into three genetic groups comprising 76, 37, and 36 members, respectively; these were classified into mixed groups with no obvious population structure. These results were consistent with those of the cluster analysis. On the whole, our data provide a starting point for the management and conservation of the current Guangxi germplasm collection as well as for their efficient use in Chinese fir-breeding programs.

Transcriptional profiles of emasculated flowers of black locust (Robinia pseudoacacia) determined using the cDNA-AFLP technique

Black locust (Robinia pseudoacacia) is a tree in the subfamily Faboideae, native to North America, that has been naturalized and widely planted in temperate Europe and Asia. Black locust has important ecological and economic value, but its quality needs improvement. Hybridization programs are important for black locust breeding, but the low rate of fruit set after controlled pollination limits both its breeding and that of other monoclinous plant species that share this problem. In this study, we investigated gene expression in emasculated black locust flowers using the cDNA-amplified fragment length polymorphism technique to determine why the rate of fruit set is low after controlled pollination. Flowers that were emasculated after being frozen in liquid nitrogen were used as controls. Changes in the flower transcriptome were more dramatic at 5 h after emasculation than at 48 h. Injury caused by emasculation decreased the expression levels of genes associated with metabolism, growth regulation, signal transduction, and photosynthesis, and it increased the expression of genes related to stress-response metabolism, signal transduction, and promotion of senescence. The changes in the expression levels of these genes had negative effects on sugar metabolism, protein metabolism, lipid metabolism, energy metabolism, matter transport, signal transduction, osmotic regulation, pH regulation, and photosynthesis. Thus, emasculation accelerated flower senescence, resulting in low fruit set.

Homology-based analysis of the GRAS gene family in tobacco

Members of the GRAS gene family are important transcriptional regulators. In this study, 21 GRAS genes were identified from tobacco, and were classified into eight subgroups according to the classification of Arabidopsis thaliana. Here, we provide a preliminary overview of this gene family in tobacco, describing the gene structure, gene expression, protein motif organization, phylogenetic analysis, and comparative analysis in tobacco, Arabidopsis, and rice. Using the sequences of 21 GRAS genes in Arabidopsis to search against the American tobacco genome database, 21 homologous GRAS genes in tobacco were identified. Sequence analysis indicates that these GRAS proteins have five conserved domains, which is consistent with their counterparts in other plants. Phylogenetic analyses divided the GRAS gene family into eight subgroups, each of which has distinct conserved domains and biological functions. Furthermore, the expression pattern of these 21 GRAS genes reveals that most are expressed in all six tissues studied; however, some have tissue specificity. Taken together, this comprehensive analysis will provide a rich resource to assist in the study of GRAS protein functions in tobacco.

Characterization of ESTs from black locust for gene discovery and marker development

Black locust (Robinia pseudoacacia L.) is an ecologically and economically important species. However, it has relatively underdeveloped genomic resources, and this limits gene discovery and marker-assisted selective breeding. In the present study, we obtained large-scale transcriptome data using a next-generation sequencing platform to compensate for the lack of black locust genomic information. Increasing the amount of transcriptome data for black locust will provide a valuable resource for multi-gene phylogenetic analyses and will facilitate research on the mechanisms whereby conserved genes and functions are maintained in the face of species divergence. We sequenced the black locust transcriptome from a cDNA library of multiple tissues and individuals on an Illumina platform, and this produced 108,229,352 clean sequence reads. The high-quality overlapping expressed sequence tags (ESTs) were assembled into 36,533 unigenes, and 4781 simple sequence repeats were characterized. A large collection of high-quality ESTs was obtained, de novo assembled, and characterized. Our results markedly expand the previous transcript catalogues of black locust and can gradually be applied to black locust breeding programs. Furthermore, our data will facilitate future research on the comparative genomics of black locust and related species.

Effects of microwave ablation or its combination with whole-body chemotherapy on serum vascular endothelial growth factor levels in patients with stage IIIB/IV NSCLC

We aimed to analyze the changes of serum vascular endothelial growth factor (VEGF) before and after microwave ablation (MWA) in patients with stage IIIB-IV non-small cell lung cancer (NSCLC), and to observe the effects of MWA combined with chemotherapy on short-term therapeutic efficacy and long-term survival. Concentrations of serum VEGF in 20 healthy subjects were considered as controls. Changes of serum VEGF were detected by ELISA before and after MWA (1 and 7 days after treatment). Seven days after MWA, patients were divided into a combination chemotherapy group of 22 subjects and a MWA alone group of 18 subjects. Serum VEGF was measured 1 month after MWA and 4 cycles after chemotherapy (3 months) to evaluate term effects; and 1- and 2-year survival rates. Serum VEGF concentrations declined sharply 1 day after MWA, and were significantly different from the levels before treatment. Subsequently, VEGF rebounded 7 days after ablation, higher than that before treatment. At 1 and 3 months, serum VEGF levels in both treatment groups were remarkably lower than that before treatment; efficiency, or for the 1-year survival rate. However, the 2-year survival rates were significantly different between the two groups. We demonstrated that after MWA, the serum VEGF concentration undergoes a process of increasing, which might promote metastasis and recurrence of NSCLC. MWA combined with whole-body chemotherapy appears to be an effective method to increase the disease control rate, reduce the probability of metastasis and recurrence, and thus improve long-term survival.

Polymorphisms in a myostatin gene and associations with growth in a hybrid of Culter alburnus and Ancherythroculter nigrocauda

Myostatin (MSTN) is a member of the transforming growth factor-β superfamily that negatively regulates skeletal muscle development and growth. In the present study, partial genomic fragments of MSTN were screened for single nucleotide polymorphisms (SNPs) in a hybrid of Culter alburnus (♀) x Ancherythroculter nigro-cauda (♂) individuals from a commercial hatchery population, and two non-synonymous SNPs (c.6T>C and c.162G>A) and two synonymous SNPs (c.152G>A and c.155G>A) in exon 2 were identified. The two non-synonymous SNPs caused an amino acid change, from Ser to Pro and from Val to Ile, respectively. Genotyping by the direct sequencing of polymerase chain reaction products for these four SNPs was conducted in 190 individuals from the commercial hatchery population. Association analysis showed that one non-synonymous SNP (c.6T>C) in exon 2 was significantly associated with total length, body length, body height, head length, and body weight. Haplotype analyses revealed that the haplotype combination H1H3 exhibited the best growth performance. Our results demonstrate that some of the SNPs in MSTN may have positive effects on growth, and suggest that MSTN could be a candidate gene for marker-assisted selection in C. alburnus and A. nigrocauda.

Cloning and expression analysis of terpenoid metabolism-related gene NsyCMS in Nicotiana sylvestris

Terpenoids constitute the main class of secondary metabolites produced in plants with industrial, pharmacological, and agricultural interests. Nicotiana sylvestris has been widely adopted as a diploid model system in plant biology for studies of terpenoid biosynthesis. In this paper, we report the isolation and analysis of the 2-C-methyl-d-erythritol 2,4-cyclodiphosphate synthase (CMS) gene of the MEP (methylerythritol 4-phosphate) pathway from N. sylvestris. We used homologous-based cloning with a RACE method to obtain the full-length coding sequence of the NsCMS. Then, the physical and chemical properties, function, and three-dimensional structure of the NsyCMS protein were predicted. Fluorogenic quantitative PCR was used to conduct an expression analysis at different developmental stages of various tissues of the NsyCMS. The sequence of the NsyCMS consists of a 954-bp open reading frame and encodes a predicted protein of 317 amino acids, with a molecular weight of approximately 49.6 kDa and pi of 6.92. The in vivo localization of the encoded protein was cytoplasmic with no signal peptide, whereas 2 transmembrane regions were found in NsyCMS. The conserved domains of typical 2-C-methyl-d-erythritol 2,4-cyclodiphosphate synthase, aminotransferase, and pyridoxal phosphate-dependent transferase were found in NsyCMS. Differential expression patterns of the NsyCMS were observed throughout the different developmental stages and tissues. NsyCMS messenger RNA was expressed in all tissues, with the highest level of expression in the seedling leaves. NsyMK was expressed at a higher level in the resettling roots. The results from our study set the foundation for exploring the terpenoid biosynthetic pathways in N. sylvestris.

Independent and joint effects of the IL-6 and IL-10 gene polymorphisms in pulmonary tuberculosis among the Chinese Han population

We investigated the association between interleukin (IL)-6 and IL-10 gene polymorphisms and the susceptibility to pulmonary tuberculosis (PTB). DNA samples were obtained from 191 Han Chinese patients with PTB and 191 healthy control subjects. IL-6 (-572, -174, -597) and IL-10 (-1082, -819) polymorphisms were analyzed using polymerase chain reaction-restriction fragment length polymorphism. The IL-6 -572 C/C and IL-10 -819 T/T genotypes were observed less frequently in the case group than in the control group, with crude odds ratios of 0.591 [95% confidence interval (CI) = 0.381-0.917] and 0.401 (95%CI = 0.257-0.627), respectively. A significant association remained after adjusting for environmental factors in multivariate logistic analysis. The homozygote genotypes of IL-6 -572 and IL-10 -819 had an adjusted OR of 0.565 (95%CI = 0.356-0.898) and 0.341 (95%CI = 0.210-0.553), respectively. These results indicate that the mutant heterozygote IL-10 -1082 A/ G+G/G genotype and the homozygote IL-10 -819 T/T genotype have a combined effect on PTB. These results suggest that the IL-6 -572 C/C and IL-10 -819 T/T genotype polymorphisms are protective factors against PTB.

Homology-based cloning and expression analysis of Rf genes encoding PPR-containing proteins in tobacco

As a model plant, mechanisms of the cytoplasmic male sterility/restoration of fertility (CMS/Rf) system in tobacco are seldom studied. Using Rf gene sequences from other Solanaceae plants and the draft genome of Nicotiana benthamiana, degenerate primers were designed to amplify the cDNA pool of N. tomentosiformis. In total, six possible Rf sequences were identified, two of which contained base-deletion mutations. The other four were intact open reading frames, of which NtomPPR5 harbored a 3-pentatricopeptide repeat (PPR) motif deletion. Structure analysis revealed that they all encoded a PPR-containing protein with putative mitochondrial targeting signals at their N-terminus, and they all belong to the P subfamily. Phylogenetic analysis showed that all of the Rf-coding PPRs clustered together, and recent duplication events might have occurred in tobacco after the divergence of the species. Quantitative reverse transcription polymerase chain reaction analysis demonstrated that the NtomRfs were expressed in all tissues of N. tomentosiformis and (CMS) K326, although the expression levels varied with gene, organ, and developmental stage. Furthermore, the expression levels of Rf sequences in K326 were lower than those in CMS K326. The molecular basis of the CMS/Rf system in tobacco requires further investigation.

Evidence for inbreeding depression in the tree Robinia pseudoacacia L. (Fabaceae)

The magnitude of inbreeding depression within populations is important for the evolution and maintenance of mixed mating systems. However, data are sparse on the magnitude of inbreeding depression in Robinia pseudoacacia. In this study, we compared differences in the mature seed set per fruit, seed mass, germination success, and seedling growth between self- and cross-pollination treatments and estimated the inbreeding depression at 3 stages: seed maturation, seedling emergence, and seedling growth at 10 and 20 weeks. We found that progenies resulting from cross-pollination treatments showed significantly higher fitness than progenies resulting from self-pollination, causing high levels of inbreeding depression. Inbreeding depression was not uniformly manifested, however, over the 3 stages. Inbreeding depression was the greatest between fertilization and seed maturation stage (δ = 0.5419), and the seedling emergence (0.3654) stage was second. No significant differences in seedling growth were observed between selfed and crossed progenies. The cumulative inbreeding depression (δ) across all 3 stages averaged 0.7452. Inbreeding depression may promote outcrossing in R. pseudoacacia by acting as a post-pollination barrier to selfing. The large difference in the seed set between self- and cross-pollination that we detected indicated that inbreeding depression would probably be a reasonable explanation for the high abortion and low seed set in R. pseudoacacia.

Experience with adrenal schwannoma in a Chinese population of six patients

OBJECTIVES

Benign adrenal schwannoma is an extremely uncommon cause of incidentaloma. This article describes our experience with the diagnosis and treatment of adrenal schwannoma in a Chinese population of 6 patients. To our knowledge, this is the largest series of this uncommon adrenal tumor treated in a single center.

METHODS

From May 1999 to May 2009, 6 patients with incidentally discovered adrenal schwannoma were operated on at a tertiary referral hospital in Eastern China. Clinical details, radiographic features, laboratory examinations, pathological findings, and follow-up data of these patients were analyzed.

RESULTS

Of the 6 patients, 4 were females (F) and 2 were males (M), with a mean age of 40.5 yr (range: 30-47, M:F=2:1). The 6 patients were managed with open unilateral adrenalectomy; 5 patients had schwannomas on the left side, and 1 on right side. Abnormal urine catecholamine was detected in 1 patient. The mean pathological size of these tumors was 4.3 ± 1.1 cm. The diagnosis of schwannoma was based on classic histological findings, and supported by immunohistochemistry of S-100, vimentin, and ABC positivity. In the follow- up of 47.5 ± 32.3 months, no recurrence and metastasis were observed.

CONCLUSIONS

Although there may be some clues for radiological diagnosis of adrenal schwannoma, preoperative misdiagnosis is not infrequent. Those tumors may occasionally have endocrine function. Histological examination is the key of diagnosis, and surgical resection is the treatment of choice once malignancy cannot be excluded by preoperative analyses.

Carvedilol reduces myocardial no-reflow by decreasing endothelin-1 via activation of the ATP-sensitive K+ channel

It has been verified that carvedilol can attenuate myocardial no-reflow. However, the effects of carvedilol on adenosine triphosphate-sensitive K+ (KATP) channel and endothelin-1 (ET-1) are unknown. Forty mini-swines were randomized into 5 study groups: 8 control, 8 carvedilol pretreatment, 8 glibenclamide (KATP channel blocker)-treated, 8 carvedilol and glibenclamide-pre-treated and 8 sham-operated. An acute myocardial infarction(AMI) and reperfusion model was created with a three-hour occlusion of the left anterior descending coronary artery followed by one-hour reperfusion. Compared with the control group, carvedilol significantly decreased the area of no-reflow (myocardial contrast echocardiography: from 78.5±4.5% to 24.9±4.1%, pathological means: from 82.3±1.9% to 25.8±4.3% of ligation area, respectively; all p < 0.01) and reduced necrosis size from 98.5±1.3% to 74.4±4.7% of ligation area, p < 0.05). It also decreased plasma ET-1 and myocardial tissue ET-1. However, glibenclamide abrogated the protective effect of carvedilol. The beneficial effect of carvedilol on myocardial no-reflow could be due to its effect on ET-1 via the activation of the KATP channel.

An updated meta-analysis of adjuvant chemotherapy after curative resection for gastric cancer

OBJECTIVES

To investigate whether and how much gastric cancer patients after curative resection could benefit from chemotherapy.

PATIENTS AND METHODS

Meta-analysis was conducted with all the qualified clinical randomized trials which compared adjuvant chemotherapy with surgery alone. The database includes MEDLINE, EMBase and CBM disc, and the censor data were up to November 2007. Primary outcomes were relative risk (RR) on death and disease-free survival (DFS); secondary outcomes include RR of adverse reactions of the two arms. Sub-group analysis and sensitivity analysis were also performed. All the calculations and statistical tests were done with the RevMan 4.2.8 software.

RESULTS

Finally, 23 trials which included 4919 patients (2441 in the adjuvant chemotherapy arm, 2478 in the observation arm) achieved all the criteria. Among them, 19 studies reported the survival rate at the end of follow-up, 60.6% alive among 2286 patients in the adjuvant chemotherapy arm, 53.4% alive among 2313 patients in the observation arm, with the RR on death of 0.85 (95%CI: 0.80-0.90). Eight studies reported the DFS, and the observation arm had a shorter DFS (RR: 0.88, 95%CI: 0.77-0.99). Grade 3/4 of myelosuppression and GI toxicity occurred more frequently in the treatment arm. Nine studies reported the recurrence rate and suggested that the treatment arm had a lower recurrence rate (RR: 0.78, 95%CI: 0.71 approximately 0.86).

CONCLUSIONS

Statistically, adjuvant chemotherapy could improve the survival rate and disease-free survival rate in gastric cancer after curative resection and reduce the relapse rate. However, the clinical benefits of adjuvant chemotherapy still need to be improved. Additionally, post-operative chemotherapy could be tolerated.

An updated meta-analysis of adjuvant chemotherapy after curative resection for gastric cancer

OBJECTIVES

To investigate whether and how much gastric cancer patients after curative resection could benefit from chemotherapy.

PATIENTS AND METHODS

Meta-analysis was conducted with all the qualified clinical randomized trials which compared adjuvant chemotherapy with surgery alone. The database includes MEDLINE, EMBase and CBM disc, and the censor data were up to November 2007. Primary outcomes were relative risk (RR) on death and disease-free survival (DFS); secondary outcomes include RR of adverse reactions of the two arms. Sub-group analysis and sensitivity analysis were also performed. All the calculations and statistical tests were done with the RevMan 4.2.8 software.

RESULTS

Finally, 23 trials which included 4919 patients (2441 in the adjuvant chemotherapy arm, 2478 in the observation arm) achieved all the criteria. Among them, 19 studies reported the survival rate at the end of follow-up, 60.6% alive among 2286 patients in the adjuvant chemotherapy arm, 53.4% alive among 2313 patients in the observation arm, with the RR on death of 0.85 (95%CI: 0.80-0.90). Eight studies reported the DFS, and the observation arm had a shorter DFS (RR: 0.88, 95%CI: 0.77-0.99). Grade 3/4 of myelosuppression and GI toxicity occurred more frequently in the treatment arm. Nine studies reported the recurrence rate and suggested that the treatment arm had a lower recurrence rate (RR: 0.78, 95%CI: 0.71 approximately 0.86).

CONCLUSIONS

Statistically, adjuvant chemotherapy could improve the survival rate and disease-free survival rate in gastric cancer after curative resection and reduce the relapse rate. However, the clinical benefits of adjuvant chemotherapy still need to be improved. Additionally, post-operative chemotherapy could be tolerated.

Identification of differentially expressed genes from the cross-subfamily cloned embryos derived from zebrafish nuclei and rare minnow enucleated eggs

Cross-species nuclear transfer (NT) has been used to retain the genetic viability of a species near extinction. However, unlike intra-species NT, most embryos produced by cross-species NT were unable to develop to later stages due to incompatible nucleo-cytoplasmic interactions between the donor nuclei and the recipient cytoplasm from different species. To study the early nucleo-cytoplasmic interaction in cross-species NT, two laboratory fish species (zebrafish and rare minnow) from different subfamilies were used to generate cross-subfamily NT embryos in the present study. Suppression subtractive hybridization (SSH) was performed to screen out differentially expressed genes from the forward and reverse subtractive cDNA libraries. After dot blot and real-time PCR analysis, 80 of 500 randomly selective sequences were proven to be differentially expressed in the cloned embryos. Among them, 45 sequences shared high homology with 28 zebrafish known genes, and 35 sequences were corresponding to 22 novel expressed sequence tags (ESTs). Based on functional clustering and literature mining analysis, up- and down-regulated genes in the cross-subfamily cloned embryos were mostly relevant to transcription and translation initiation, cell cycle regulation, protein binding, etc. To our knowledge, this is the first report on the determination of genes involved in the early development of cross-species NT embryos of fish.

Survival of faecal coliforms and hygiene risks in soils treated with municipal sewage sludges

An incubation experiment was conducted to monitor effect of sewage sludge application on changes in numbers of faecal coliforms in soils over time after sludge application and evaluate the hygiene risks. Soil faecal coliform counts were made after 1, 7, 14, 28, 56 and 84 days of incubation. The faecal coliform counts in the sludge-treated soils decreased substantially with time and were similar to those in the untreated controls after incubation for 56 days. Land application of air-dried sludges increased the hygiene risks due to the re-growth of faecal coliforms, and the counts of faecal coliforms in soil treated with air dried sludge from Suzhou (91% DM) were 50 times higher than in soils with fresh dewatered sludge from Suzhou (15% DM) after 7 days of incubation. The main factors affecting the changes in faecal coliform counts were sludge type and incubation time. Sludge type determined the faecal coliform counts and the ability of the faecal coliforms to re-establish, and indigenous microorganisms competed with the faecal coliforms for nutrients during the incubation process.