Can hemozoin alone cause host anaemia?

Both schistosomes and malaria parasites produce hemozoin and cause host anaemia. However, the relationship between anaemia and hemozoin is unclear. Although some studies have proposed that hemozoin is related to anaemia in malaria patients, whether hemozoin alone can cause anaemia in patients infected by malaria parasites or schistosomes is uncertain. To investigate the effect of hemozoin on hosts, ß-haematin was injected intravenously to normal mice. Then, liver and spleen tissues were observed. Mouse blood was examined. Red blood cells (RBCs), white blood cells (WBCs) and haemoglobin were analysed. Macrophage changes in the spleens and marrow cells were compared using immunofluorescence and H&E or Giemsa stain, respectively. We found that after 15 injections of ß-haematin, a large amount of ß-haematin was observed to deposit in the livers and spleens. Splenomegaly and bone marrow mild hyperplasia were detected. The average number of RBCs, average number of WBCs and average concentration of haemoglobin decreased significantly from 9.36 × 1012 cells/L to 8.7 × 1012 cells/L, 3.8 × 109 cells/L to 1.7 × 109 cells/L and 142.8 g/L to 131.8 g/L, respectively. In specific, the number of macrophages in the spleens greatly increased after ß-haematin infection. The results showed that injections of ß-haematin alone can cause anaemia possibly through hypersplenism.

ATP synthase: an identified target gene of bantam in paired female Schistosoma japonicum.

MicroRNAs (miRNAs) are a class of small non-coding RNAs that function in transcriptional and post-transcriptional regulation of gene expression. An increasing number of schistosome miRNAs have been identified and are expected possibly involved in differentiation, development, and metabolism. However, limited information is available concerning the target genes of schistosome miRNAs. In the present study, the key target genes of bantam, an abundant miRNA found in paired female Schistosoma japonicum, were predicted by bioinformatics analysis and Solexa technology. Luciferase reporter assay and bantam mimic assay were applied in combination to further verify the targets of bantam. Results showed that ATP synthase (CAX76793.1), one of the three selected predicted targets, was confirmed as the target of bantam; bantam mimic assay results also showed that the two other predicted targets, namely, ataxia telangiectasia mutated (ATM)-related (XP_002571630.1), and ribosomal protein L30 (CAX72575.1), were not confirmed as targets. This research proposed the design and significance of reasonable biological experiments that could be performed to identify miRNA target genes in schistosomes.

Transcriptome profilings of female Schistosoma japonicum reveal significant differential expression of genes after pairing.

Pairing of Schistosoma japonicum initiates female development, leads to female sexual maturation, and maintains this mature state. To understand the mechanism involved in these processes, we studied parasites isolated from single- and double-sex cercariae-infected mice using deep-sequencing analysis, Solexa, to uncover pair-regulated transcriptional profiles. In this study, we report the results of high-throughput tag-sequencing (Tag-seq) analysis of the transcriptome of female worms 18 and 23 days postsingle- and double-sex infections. We sequenced over 3 million tags, obtained a total of 14,034, 27,251, 22,755, and 22,555 distinct tags corresponding to 5,773, 9,794, 8,885, and 8,870 tag-mapped genes for 23-day-old female schistosomula from double-sex infections (23DSI), 23-day-old female schistosomula from single-sex infections (23SSI), 18-day-old female schistosomula from double-sex infections (18DSI), and 18-day-old female schistosomula from single-sex infections (18SSI), respectively. Analyses of differentially expressed genes revealed similarities in the gene expression profiles between 18SSI and 18DSI as well as rational differential gene expression between 18SSI and 23SSI. However, fewer upregulated genes were found in 23DSI compared with 18DSI. Of the 3,446 differentially expressed genes between 23DSI and 23SSI, 2,913 genes were upregulated in 23SSI, whereas only 533 genes were upregulated in 23DSI. In these upregulated genes in 23DSI, phosphoglycerate mutase, superoxide dismutase, egg antigen, ribosomal proteins, ferritin-1 heavy chain, and eukaryotic translation initiation factor 2 were detected. Detection of these genes suggests that gene expression in 23DSI is specialized for functions such as promotion and maintenance of female sexual maturation and egg production. Quantitative real-time (RT)-PCR analysis confirmed the Solexa results, thereby supporting the reliability of the system. Our results offer new insights into the biological significance of pairing, which directs the expression of genes specific for sexual maturation and egg production.

[Advances on antitumor effect of parasites].

Immune response induced by parasites could inhibit tumor growth and promote apoptosis of tumor cells. The investigation into this character will provide new insights on the anti-tumor effect of parasites. The mechanism of parasite immune evasion may provide a reference for tumor research. Furthermore, some anti-parasitic drugs have shown antitumor effect indicating that the development of antitumor drugs may get inspiration from anti-parasitic drug studies.

Prevalence of depression and anxiety in patients with chronic digestive system diseases: A multicenter epidemiological study.

AIM: To investigate the prevalence of depression and anxiety in patients with chronic digestive system diseases. METHODS: A total of 1736 patients with chronic digestive system diseases were included in this cross-sectional study, including 871 outpatients and 865 in-patients. A self-designed General Information for Patients of the Department of Gastroenterology of General Hospitals questionnaire was used to collect each patient's general information, which included demographic data (including age, sex, marital status, and education) and disease characteristics (including major diseases, disease duration, principal symptoms, chronic pain, sleep disorder, and limited daily activities). RESULTS: The overall detection rate was 31.11% (540/1736) for depression symptoms alone, 27.02% (469/1736) for anxiety symptoms alone, 20.68% (359/1736) for both depression and anxiety symptoms, and 37.44% (650/1736) for either depression or anxiety symptoms. Subjects aged 70 years or above had the highest detection rate of depression (44.06%) and anxiety symptoms (33.33%). χ2 trend test showed: the higher the body mass index (BMI), the lower the detection rate of depression and anxiety symptoms (χ2trend = 13.697, P < 0.001; χ2trend = 9.082, P = 0.003); the more severe the limited daily activities, the higher the detection rate of depression and anxiety symptoms (χ2trend = 130.455, P < 0.001, χ2trend = 108.528, P < 0.001); and the poorer the sleep quality, the higher the detection rate of depression and anxiety symptoms (χ2trend = 85.759, P < 0.001; χ2trend = 51.969, P < 0.001). Patients with digestive system tumors had the highest detection rate of depression (57.55%) and anxiety (55.19%), followed by patients with liver cirrhosis (41.35% and 48.08%). Depression and anxiety symptoms were also high in subjects with comorbid hypertension and coronary heart disease. CONCLUSION: Depression and anxiety occur in patients with tumors, liver cirrhosis, functional dyspepsia, and chronic viral hepatitis. Elderly, divorced/widowed, poor sleep quality, and lower BMI are associated with higher risk of depression and anxiety.

Mutations in hepatitis B virus core regions correlate with hepatocellular injury in Chinese patients with chronic hepatitis B.

AIM: To elucidate the relationship between the frequency of core mutations and the clinical activity of hepatitis B virus (HBV)-related liver disease and to characterize the amino acid changes in the core region of HBV. METHODS: We studied 17 Chinese patients with chronic hepatitis B according to their clinical courses and patterns of the entire core region of HBV. RESULTS: Amino acid changes often appeared in the HBV core region of the HBV gene in patients with high values of alanine aminotransferase (ALT) or with the seroconversion from HbeAg to anti-HBe. The HBV core region with amino acid changes had high frequency sites that corresponded to HLA I/II restricted recognition epitopes reported by some investigators. CONCLUSION: The core amino acid changes of this study occur due to influence of host immune system. The presence of mutations in the HBV core region seems to be important for predicting the clinical activity of hepatitis B in Chinese patients.