Morphological and molecular characteristics of a Trypanosoma sp. from triatomines (Triatoma rubrofasciata) in China.

BACKGROUND: Triatomines (kissing bugs) are natural vectors of trypanosomes, which are single-celled parasitic protozoans, such as Trypanosoma cruzi, T. conorhini and T. rangeli. The understanding of the transmission cycle of T. conorhini and Triatoma rubrofasciata in China is not fully known. METHODS: The parasites in the faeces and intestinal contents of the Tr. rubrofasciata were collected, and morphology indices were measured under a microscope to determine the species. DNA was extracted from the samples, and fragments of 18S rRNA, heat shock protein 70 (HSP70) and glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) were amplified and sequenced. The obtained sequences were then identified using the BLAST search engine, followed by several phylogenetic analyses. Finally, laboratory infections were conducted to test whether Tr. rubrofasciata transmit the parasite to rats (or mice) through bites. Moreover, 135 Tr. rubrofasciata samples were collected from the Guangxi region and were used in assays to investigate the prevalence of trypanosome infection. RESULTS: Trypanosoma sp. were found in the faeces and intestinal contents of Tr. rubrofasciata, which were collected in the Guangxi region of southern China and mostly exhibited characteristics typical of epimastigotes, such as the presence of a nucleus, a free flagellum and a kinetoplast. The body length ranged from 6.3 to 33.9 µm, the flagellum length ranged from 8.7 to 29.8 µm, the nucleus index was 0.6 and the kinetoplast length was -4.6. BLAST analysis revealed that the 18S rRNA, HSP70 and gGAPDH sequences of Trypanosoma sp. exhibited the highest degree of similarity with those of T. conorhini (99.7%, 99.0% and 99.0%, respectively) and formed a well-supported clade close to T. conorhini and T. vespertilionis but were distinct from those of T. rangeli and T. cruzi. Laboratory experiments revealed that both rats and mice developed low parasitaemia after inoculation with Trypanosoma sp. and laboratory-fed Tr. rubrofasciata became infected after feeding on trypanosome-positive rats and mice. However, the infected Tr. rubrofasciata did not transmit Trypanosoma sp. to their offspring. Moreover, our investigation revealed a high prevalence of Trypanosoma sp. infection in Tr. rubrofasciata, with up to 36.3% of specimens tested in the field being infected. CONCLUSIONS: Our study is the first to provide a solid record of T. conorhini from Tr. rubrofasciata in China with morphological and molecular evidence. This Chinese T. conorhini is unlikely to have spread through transovarial transmission in Tr. rubrofasciata, but instead, it is more likely that the parasite is transmitted between Tr. rubrofasciata and mice (or rats). However, there was a high prevalence of T. conorhini in the Tr. rubrofasciata from our collection sites and numerous human cases of Tr. rubrofasciata bites were recorded. Moreover, whether these T. conorhini strains are pathogenic to humans has not been investigated.

Clonorchis sinensis infection amplifies hepatocellular carcinoma stemness, predicting unfavorable prognosis.

BACKGROUND: Extensive evidence links Clonorchis sinensis (C. sinensis) to cholangiocarcinoma; however, its association with hepatocellular carcinoma (HCC) is less acknowledged, and the underlying mechanism remains unclear. This study was designed to investigate the association between C. sinensis infection and HCC and reveal the relationship between C. sinensis infection and cancer stemness. METHODS: A comprehensive analysis of 839 HCC patients categorized into C. sinensis (-) HCC and C. sinensis (+) HCC groups was conducted. Chi-square and Mann-Whitney U tests were used to assess the association between C. sinensis infection and clinical factors. Kaplan-Meier and Cox regression analyses were used to evaluate survival outcomes. Immunohistochemistry was used to determine CK19 and EpCAM expression in HCC specimens. RESULTS: Compared to C. sinensis (-) HCC patients, C. sinensis (+) HCC patients exhibited advanced Barcelona Clinic Liver Cancer (BCLC) stage, higher male prevalence and more liver cirrhosis as well as elevated alpha-fetoprotein (AFP), carbohydrate antigen 19-9 (CA19-9), eosinophil, complement 3 (C3), and complement 4 (C4) values. C. sinensis infection correlated with shorter overall survival (OS) (p < 0.05) and recurrence-free survival (RFS) (p < 0.05). Furthermore, Cox multivariate analysis revealed that C. sinensis infection was an independent prognostic factor for OS in HCC patients. Importantly, C. sinensis infection upregulated the expression of HCC cancer stem cell markers CK19 and EpCAM. CONCLUSION: HCC patients with C. sinensis infection exhibit a poor prognosis following hepatectomy. Moreover, C. sinensis infection promotes the acquisition of cancer stem cell-like characteristics, consequently accelerating the malignant progression of HCC. AUTHOR SUMMARY: Clonorchis sinensis (C. sinensis) is a prominent food-borne parasite prevalent in regions such as China, particularly in Guangxi. C. sinensis has been associated with various hepatobiliary system injuries, encompassing inflammation, periductal fibrosis, cholangiocarcinoma and even hepatocellular carcinoma (HCC). A substantial body of evidence links C. sinensis to cholangiocarcinoma, However, the connection between C. sinensis and HCC and the intricate mechanisms underlying its contribution to HCC development remain incompletely elucidated. Our study demonstrates clear clinicopathological associations between C. sinensis and HCC, such as gender, BCLC stage, liver cirrhosis, MVI, AFP, CA19-9, circulating eosinophils and complements. Furthermore, we found that the co-occurrence of C. sinensis exhibited a significant association with shorter OS and RFS in patients diagnosed with HCC. A major finding was that C. sinensis infection promotes the acquisition of cancer stem cell-like characteristics, consequently accelerating the malignant progression of HCC. Our results provide a more comprehensive comprehension of the interplay between C. sinensis and HCC, shedding fresh light on the carcinogenic potential of C. sinensis.

Multi-omics approaches reveal the molecular mechanisms underlying the interaction between Clonorchis sinensis and mouse liver.

Introduction: Clonorchiasis remains a serious global public health problem, causing various hepatobiliary diseases. However, there is still a lack of overall understanding regarding the molecular events triggered by Clonorchis sinensis (C. sinensis) in the liver. Methods: BALB/c mouse models infected with C. sinensis for 5, 10, 15, and 20 weeks were constructed. Liver pathology staining and observation were conducted to evaluate histopathology. The levels of biochemical enzymes, blood routine indices, and cytokines in the blood were determined. Furthermore, alterations in the transcriptome, proteome, and metabolome of mouse livers infected for 5 weeks were analyzed using multi-omics techniques. Results: The results of this study indicated that adult C. sinensis can cause hepatosplenomegaly and liver damage, with the most severe symptoms observed at 5 weeks post-infection. However, as the infection persisted, the Th2 immune response increased and symptoms were relieved. Multi-omics analysis of liver infected for 5 weeks identified 191, 402 and 232 differentially expressed genes (DEGs), proteins (DEPs) and metabolites (DEMs), respectively. Both DEGs and DEPs were significantly enriched in liver fibrosis-related pathways such as ECM-receptor interaction and cell adhesion molecules. Key molecules associated with liver fibrosis and inflammation (Cd34, Epcam, S100a6, Fhl2, Itgax, and Retnlg) were up-regulated at both the gene and protein levels. The top three metabolic pathways, namely purine metabolism, arachidonic acid metabolism, and ABC transporters, were associated with liver cirrhosis, fibrosis, and cholestasis, respectively. Furthermore, metabolites that can promote liver inflammation and fibrosis, such as LysoPC(P-16:0/0:0), 20-COOH-leukotriene E4, and 14,15-DiHETrE, were significantly up-regulated. Conclusion: Our study revealed that the most severe symptoms in mice infected with C. sinensis occurred at 5 weeks post-infection. Moreover, multi-omics analysis uncovered predominant molecular events related to fibrosis changes in the liver. This study not only enhances our understanding of clonorchiasis progression but also provides valuable insights into the molecular-level interaction mechanism between C. sinensis and its host liver.

Multilayer omics reveals the molecular mechanism of early infection of Clonorchis sinensis juvenile.

BACKGROUND: Clonorchiasis remains a non-negligible global zoonosis, causing serious socioeconomic burdens in endemic areas. Clonorchis sinensis infection typically elicits Th1/Th2 mixed immune responses during the course of biliary injury and periductal fibrosis. However, the molecular mechanism by which C. sinensis juvenile initially infects the host remains poorly understood. METHODS: The BALB/c mouse model was established to study early infection (within 7 days) with C. sinensis juveniles. Liver pathology staining and observation as well as determination of biochemical enzymes, blood routine and cytokines in blood were conducted. Furthermore, analysis of liver transcriptome, proteome and metabolome changes was performed using multi-omics techniques. Statistical analyses were performed using Student's t-test. RESULTS: Histopathological analysis revealed that liver injury, characterized by collagen deposition and inflammatory cell infiltration, occurred as early as 24 h of infection. Blood indicators including ALT, AST, WBC, CRP and IL-6 indicated that both liver injury and systemic inflammation worsened as the infection progressed. Proteomic data showed that apoptosis and junction-related pathways were enriched within 3 days of infection, indicating the occurrence of liver injury. Furthermore, proteomic and transcriptomic analysis jointly verified that the detoxification and antioxidant defense system was activated by enrichment of glutathione metabolism and cytochrome P450-related pathways in response to acute liver injury. Proteomic-based GO analysis demonstrated that biological processes such as cell deformation, proliferation, migration and wound healing occurred in the liver during the early infection. Correspondingly, transcriptomic results showed significant enrichment of cell cycle pathway on day 3 and 7. In addition, the KEGG analysis of multi-omics data demonstrated that numerous pathways related to immunity, inflammation, tumorigenesis and metabolism were enriched in the liver. Besides, metabolomic screening identified several metabolites that could promote inflammation and hepatobiliary periductal fibrosis, such as CA7S. CONCLUSIONS: This study revealed that acute inflammatory injury was rapidly triggered by initial infection by C. sinensis juveniles in the host, accompanied by the enrichment of detoxification, inflammation, fibrosis, tumor and metabolism-related pathways in the liver, which provides a new perspective for the early intervention and therapy of clonorchiasis.

Effects of tolC on tolerance to bile salts and biofilm formation in Cronobacter malonaticus.

Bile salts is one of essential components of bile secreted into the intestine to confer antibacterial protection. Cronobacter species are associated with necrotizing enterocolitis in newborns and show a strong tolerance to bile salts. However, little attempt has been made to focus on the molecular basis of the tolerance to bile salts. In this study, we investigated the roles of tolC on growth, cell morphology, motility, and biofilm formation ability in Cronobacter malonaticus under bile salt stress. The results indicated that the absence of tolC significantly affected the colony morphology and outer membrane structure in a normal situation, compared with those of the wild type strain. The deletion of tolC caused the decline in resistance to bile salt stress, inhibition of growth, and observable reduction in relative growth rate and motility. Moreover, the bacterial stress response promoted the biofilm formation ability of the mutant strain. The expression of the AcrAB-TolC system (acrA, acrB, and tolC) was effectively upregulated compared with the control sample when exposed to different bile salt concentrations. The findings provide valuable information for deeply understanding molecular mechanisms about the roles of tolC under bile salt stress and the prevention and control of C. malonaticus.

Role of fliC on biofilm formation, adhesion, and cell motility in Cronobacter malonaticus and regulation of luxS.

Cronobacter malonaticus is one of the important foodborne pathogens causing infections mainly in adults. Biofilm formation, adhesion, and motility in Cronobacter have been documented, but the implying molecular mechanism has received little attention. Here, a comparison in biofilm formation, adhesion ability, and cell motility among wild type (WT), △luxS, and △fliC strains were analyzed using scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM). The thickest biofilm was formed by WT, followed by △luxS and △fliC. Furthermore, the deletion of fliC caused the loss of cell motility and the failure to flagella biosynthesis and mature biofilm formation. Besides, the adhesion abilities of △luxS and △fliC to biotic cells (LoVo and IEC-6) and abiotic surface (glass) were significantly decreased compared to WT, revealing that fliC might have an important role in the organism's invasion properties. We further demonstrated that the expression of negative regulator (flgM) of flagellin in △luxS was higher than that in WT, which indicated that luxS indirectly contributed to fliC expression. Our findings provided a novel perspective for precaution and control of C. malonaticus through intercepting fliC-mediated adhesion to biotic cells and abiotic surface.

Role of the multiple efflux pump protein TolC on growth, morphology, and biofilm formation under nitric oxide stress in Cronobacter malonaticus.

Nitric oxide (NO) is a biological signal molecule that can control and prevent the growth of most pathogens. Cronobacter species are a group of gram-negative foodborne pathogens that cause severe diseases, including neonatal meningitis, septicemia, and necrotizing enterocolitis, especially among newborns and infants consuming contaminated powdered infant formula. Cronobacter species might be tolerant to NO, resulting in severe infections. However, the specific mechanism of tolerance to NO in Cronobacter species is unclear. Here, we explore the effects of a key component, the protein TolC, of a multiple efflux pump on the growth, morphological changes, and biofilm formation of Cronobacter malonaticus under NO stress. We found that deletion of tolC resulted in a decreased growth rate under 100 mM sodium nitroprusside (NO donor) and led to more disruptive morphological injury to the bacterial cells. Furthermore, C. malonaticus lacking the TolC protein (ΔtolC mutant) showed weaker biofilm formation than the wild-type strain under normal or NO stress conditions. We have proved that TolC plays an important role in cell growth and biofilm formation of C. malonaticus. Therefore, our results may provide valuable theoretical basis for formulating clinical guidelines for treatment of disease caused by C. malonaticus and ensuring food safety.

Schistosoma japonicum SjE16.7 Protein Promotes Tumor Development via the Receptor for Advanced Glycation End Products (RAGE).

Schistosome infection contributes to cancer development, but the mechanisms are still not well-understood. SjE16.7 is an EF-hand calcium-binding protein secreted from Schistosoma japonicum eggs. It is a neutrophil attractant and macrophage activator and, as such, plays an important role in the inflammatory granuloma response in schistosomiasis. Here, we show that SjE16.7 binds to host cells by interacting with receptors for advanced glycation end products (RAGE). This ligation leads to activation of the NF-κB signaling pathway, an increase in the generation of reactive oxygen species, and production of the pro-inflammatory cytokines IL-6 and TNF-α. Using a mouse model of colorectal cancer, we demonstrate that intraperitoneal injection of SjE16.7 promotes colorectal cancer progression along with systemic myeloid cell accumulation. Thus, our results identify a new helminth antigen contributing to tumor development in the mammalian host.

Characterization of a non-sexual population of Strongyloides stercoralis with hybrid 18S rDNA haplotypes in Guangxi, Southern China.

Strongyloidiasis is a much-neglected but sometimes fatal soil born helminthiasis. The causing agent, the small intestinal parasitic nematode Strongyloides stercoralis can reproduce sexually through the indirect/heterogonic life cycle, or asexually through the auto-infective or the direct/homogonic life cycles. Usually, among the progeny of the parasitic females both, parthenogenetic parasitic (females only) and sexual free-living (females and males) individuals, are present simultaneously. We isolated S. stercoralis from people living in a village with a high incidence of parasitic helminths, in particular liver flukes (Clonorchis sinensis) and hookworms, in the southern Chinese province Guangxi. We determined nuclear and mitochondrial DNA sequences of individual S. stercoralis isolated from this village and from close by hospitals and we compared these S. stercoralis among themselves and with selected published S. stercoralis from other geographic locations. For comparison, we also analyzed the hookworms present in the same location. We found that, compared to earlier studies of S. stercoralis populations in South East Asia, all S. stercoralis sampled in our study area were very closely related, suggesting a recent common source of infection for all patients. In contrast, the hookworms from the same location, while all belonging to the species Necator americanus, showed rather extensive genetic diversity even within host individuals. Different from earlier studies conducted in other geographic locations, almost all S. stercoralis in this study appeared heterozygous for different sequence variants of the 18S rDNA hypervariable regions (HVR) I and IV. In contrast to earlier investigations, except for three males, all S. stercoralis we isolated in this study were infective larvae, suggesting that the sampled population reproduces predominantly, if not exclusively through the clonal life cycles. Consistently, whole genome sequencing of individual worms revealed higher heterozygosity than reported earlier for likely sexual populations of S. stercoralis. Elevated heterozygosity is frequently associated with asexual clonal reproduction.

Preparation and biocompatibility of Fe50Ni50p/HAP/PEEK biocomposites with weak magnetic properties.

Hydroxyapatite (HAP)/polyetheretherketone (PEEK) composites are widely used in the new generation of bone implant materials. The use of weak magnetic fields can promote the biocompatibility of PEEK materials. In this paper, Fe50Ni50 alloy nanopowders and Fe50Ni50/HAP/PEEK composites were prepared by liquid phase chemical reduction and liquid phase mixing. The prepared Fe50Ni50 alloy nanopowders have a particle size of about 100 nm and good chemical activity and magnetic properties. The saturation magnetization (M s) of the Fe50Ni50 alloy powders is 70 emu g-1. Fe50Ni50 nano-powders in Fe50Ni50/HAP/PEEK composites are uniformly distributed in the matrix in the form of individual particles, achieving nano-level dispersion. With the increase of Fe50Ni50 alloy powders content, the magnetic properties of the composites are significantly enhanced. The biocompatibility of Fe50Ni50/HAP/PEEK composites is significantly better than that of PEEK and HAP/PEEK materials. The 2% Fe50Ni50/HAP/PEEK composite has the best comprehensive performance, and its biocompatibility is good. The contact angle is only 55.85°. The M s reaches 1.5 emu g-1 and the hardness reaches 42 HBa.

A novel genotype screening and phylogenetic analysis of Blastocystis hominis based on EF-1α.

Blastocystis hominis (B. h) is a kind of intestinal parasitic protozoa with the characteristic of worldwide distribution, morphology diversity, and diarrhea induced, etc. The traditional morphological classify was difficult to distinguish the genetic difference of B. h in different population and different geological strains. Recently, based on the small subunit ribosomal DNA sequence of B. h, the sequenced-tagged site (STS) primers was design, and successfully and widely applied to the distinguish the genotype of B. h, and however several B. h strains did not distinguish. To address it, the elongation factor-1 alpha (EF-1α) gene of B. h was screened due to its conservation here, and its specific primers were designed to distinguish the genotype of B. h. After epidemiological survey, the infection rate of B. h in boys was 14.74%, and that of girls was 15.05%, and the total infection rate of B. h was 14.93%. In total of 53 infection students, with the using of 7 pairs STS primers, 31 strains was validated by polymerase chain reaction (PCR), including 4 strains of Type 1, 17 strains of Type 3, 4 strains of Type 4, 1 strains of Type 6, and 5 strains of Type 7, and did not found the Type 2, Type 5 and mixture genotype. In the 23 unknown genotype strains of B. h, 15 strains were identified by PCR using EF-1α primers, and had a higher homology in the DNA sequence (70%), and was evolutionarily closer to the EF-1α sequence of S and H strains of B. h. This study indicated that STS primers could identify the genotype of B. h, and EF-1α primers as a novel diagnosis primers could auxiliary identify the unknown genotype strain of B. h, and exhibited a wide application on the identification of the genotype strain of B. h, and provided a significant reference on the study of B. h in clinic.

Comparative analysis of intestinal parasitic infections of outpatients in Guangxi medical university affiliated hospital in 2005 and 2013.

OBJECTIVE: To understand the hospital's status and trends of intestinal parasitic infections and to provide a reference for prevention. METHODS: Stool samples were treated by acid-ether centrifugation; iodine staining and direct-smearing were performed; intestinal parasites were examined under a microscope; characteristics of parasitic infections in population were analyzed using the descriptive epidemiological method. RESULTS: 10 kinds of parasites were detected; the infection rate of clonorchissinensis was the highest, followed by B. hominis, hookworm, whipworm and roundworm in order (x(2) = 131.188, 1261.928, 129.386, P < 0.01); The overall infection rates in 2013 and 2005 were 37.08% and 41.07% respectively, and the infection rate in 2013 was lower than that in 2005 (x(2) = 20.5003, P < 0.01); All the infection rates of clonorchissinensis, hookworm, whipworm and roundworm in 2013 were lower than those in 2005 (x(2) = 18.275, 45.449, 34.855, 12.435, P < 0.01); Both in 2005 and 2013, the male infection rate was higher than that in female (x(2) = 12.859, 24.924, P < 0.01); For male, the infection rate of clonorchissinensis was the highest, followed by B. hominis (x(2) = 313.621, 104.409, P < 0.01); for female, the infection rate of B. hominis was the highest, followed by clonorchissinensis (x(2) = 95.293, 43.357, P < 0.01). For male, the age group of 41~ had the highest infection rate of clonorchissinensis in 2005 (x(2) = 5.734, P < 0.05), and the age groups of 31~ and 41~ had the highest infection rate of clonorchissinensis in 2013 (x(2) = 8.908, P < 0.01); for female, both in 2005 and 2013, the age group of 21~, 31~, 41~ and 51~ had the highest infection rate of clonorchissinensis (x(2) = 6.508, 5.145, P < 0.05). There was no difference in male infection rate of B. hominis in 2005 (x(2) = 10.134, P > 0.05); in 2013, the age group of 0~ had the highest infection rate (x(2) = 3.825, P < 0.05); for women, it was the highest in the age groups of 11~, 21~ and 31~ in 2005 (x(2) = 10.459, P < 0.01), 0~ and 11~ in 2013 (x(2) = 53.669, P < 0.01). For Hookworm infection in male, the highest infection rate was found in the age group of 11~ 21~ and 61~ in 2005 (x(2) = 4.547, P < 0.05), 61~ and ≥ 71~ in 2013 (x(2) = 4.843, P < 0.05); for female, the highest infection rate was found in the age groups of 51~ and 61~ both in 2005 and 2013 (x(2) = 5.709, 5.958, P < 0.05). CONCLUSION: In Nanning city, although there was a decline in the infection rate of intestinal parasites of attenders compared with 8 years ago, the infection rate was still high and intestinal parasites were various; The infection rate of geohelminthes had been reduced to a low level; Clonorchissinensis and B. hominis were still the insect species with the highest infection rate.

Cloning, expression, and partial characterization of FBPA from Schistosoma japonicum, a molecule on that the fluke may develop nutrition competition and immune evasion from human.

Carbohydrate metabolism is the most important physiological process for Schistosoma japonicum which resides in host. However, as a key glycolytic enzyme in carbohydrate metabolism, fructose-1,6-bisphosphate aldolase (FBPA), there is no study on its enzymatic kinetics and antigenic peptides. Here, we report the gene cloning, expression, purification, and kinetics of the FBPA from S. japonicum (sjFBPA). After cloning, sjFBPA gene was introduced into pET-28a and transformed BL21, and a soluble His6-sjFBPA was expressed and purified successfully at the expected molecular mass of ~45 kDa. We first reported that the diversities in IGS regions and the features of residues position 346 and 357-362 of sjFBPA may be conferred either through conformational changes influencing easily the active site from a distance and/or causing the C-terminal region to interact directly with the active site, which lead His6-sjFBPA to exhibit a higher specific activity of 197.43 units/mg and degrades FBP with a typical substrate inhibition model and a higher efficiency of k cat = 6261.3/s and K m = 0.061 µM than human aldolases, which might be the strategy that S. japonicum gaining energy and surviving in its environment with low concentration of carbohydrate, and benefitting to get more metabolic substances for parasites in nutrition competition with their host. sjFBPA exhibits a high similarity of 81.46 % with that of hosts, especially in antigenic peptide regions, and 14 of 15 antigenic peptides of sjFBPA were conserved to those of human aldolase A, B, and/or C with high identity (17, 16, or 16 antigenic peptides, respectively), which may result in a molecular mimicry of FBPA with that of host, and an immune evasion from their hosts. This work would supply an experimental base for using FBPA to prevent the schistosomiasis in the future.

[PCR-based genotype classification of Blastocystis hominis isolates from college students of Guangxi].

Fifty-three Blastocystis hominis isolates were separated from the fecal specimens of carriers in college students from Guangxi and cultivated in vitro, and the genetic DNA was extracted. All the isolates were genotyped by PCR using seven pairs of known sequence-tagged site (STS) primers. The results showed there were five subtypes in the 53 isolates. Subtype 3 was the most popular one (32.1%, 17/53), followed by subtype 7 (9.4%, 5/53). Subtypes 1 (7.6%, 4/53), 4 (7.6%, 4/53), and 6 (1.9%, 1/53) were detected, while subtypes 2 and 5 were not detected. The genotypes of the other 22 isolates were unknown which were negative to all the STS primers.

Efficient space-time sampling with pixel-wise coded exposure for high-speed imaging.

Cameras face a fundamental trade-off between spatial and temporal resolution. Digital still cameras can capture images with high spatial resolution, but most high-speed video cameras have relatively low spatial resolution. It is hard to overcome this trade-off without incurring a significant increase in hardware costs. In this paper, we propose techniques for sampling, representing, and reconstructing the space-time volume to overcome this trade-off. Our approach has two important distinctions compared to previous works: 1) We achieve sparse representation of videos by learning an overcomplete dictionary on video patches, and 2) we adhere to practical hardware constraints on sampling schemes imposed by architectures of current image sensors, which means that our sampling function can be implemented on CMOS image sensors with modified control units in the future. We evaluate components of our approach, sampling function and sparse representation, by comparing them to several existing approaches. We also implement a prototype imaging system with pixel-wise coded exposure control using a liquid crystal on silicon device. System characteristics such as field of view and modulation transfer function are evaluated for our imaging system. Both simulations and experiments on a wide range of scenes show that our method can effectively reconstruct a video from a single coded image while maintaining high spatial resolution.

[Relationship between morphology and pathogenicity of Blastocystis hominis trophozoites].

Six hundred and eighty-six fresh fecal specimens were collected from outpatients (663 well-formed feces and 23 watery feces) during March 2011 to March 2012. All specimens were examined microscopically by direct smear and iodine stained method. B. hominis obtained from the human positive fecal specimens were cultured in LES medium, and inoculated into the abdominal cavity of 10 female mice of 6-8-week old. The abdominal fluid was examined with same methods. 103 of 686 patients were positive (80 well-formed feces and 23 watery feces). Micro-scopically, the granular form and vacuolated form of B. hominis trophozoites could be easily identified by direct smear and iodine staining in well-formed fecal specimens, showing ovoid in shape and about (13.2 +/- 0.2) microm in size. The trophozoites cultured in LES medium showed similar feature. But in the watery fecal specimens and mice ascites specimen, they were amorphous containing more granules. And their average size was (28.0 +/- 0.3) microm which was larger than the former. Moreover, the ameba form of B. hominis trophozoites was also detected in the 23 watery fecal specimen and mice ascites specimen. The trophozoites of B. hominis were varying in shape and size depending on their living environment.

[Expressions and significance of IL-17 and IL-23 in intestinal mucosa of mice infected with Blastocystis hominis].

OBJECTIVE: To study the expressions of interleukin-17 (IL-17) and interleukin-23 (IL-23) in the intestinal mucosa of BABL/C mice infected with Blastocystis hominis. METHODS: A total of 30 BABL/C mice were randomly divided into different groups: an experimental group, an immunosuppressant group and a normal group. Each mouse of the experimental group and immunosuppressant group was administered intraperieneally with dexamethasone (2 mg, gd, for 5 days) and one of the control group was given physiological saline (0.2 ml). In the experimental group, each mouse was infected with Blastocystis hominis (107 parasites per 0.5 ml) by the intragastric infusion method; in the immunosuppressant group and normal group, the mice were fed with equal physiological saline. On the fifth day post-infection, the duodenum, jejunum, ileum and colon of the mice of the 3 groups were taken out for the tissue section. The pathological changes of bowel mucosa were determined by HE staining, and the expressions of IL-17 and IL-23 in different parts of bowel mucosa were determined by immunohistochemistry assay. RESULTS: The pathological examinations showed intestinal mucosa had various degrees of inflammatory changes. The expressions of IL-17 and IL-23 in the intestinal mucosa of the mice in the experimental group was significantly higher than those in the immunosuppressant group or normal group (both P < 0.05). The expressions of IL-17 and IL-23 in the intestinal mucosa of the mice in the immunosuppressant group were similar to those in the normal group (P > 0.05). The expression of IL-17 in the duodenum or jejunum or colon of the mice was significantly higher than that in the ileum in the experimental group (P < 0.05). The expression of IL-23 in the duodenum or jejunum of the mice was significantly higher that that in the ileum or colon in the experimental group (P < 0.05). CONCLUSIONS: IL-17 and IL-23 are highly expressed in the intestinal mucosa of the mice infected with Blastocystis hominis. IL-23 may also be involved in the immunomodulatory effects of Blastocystis hominis infection, which plays a mutual regulatory role with IL-17.

Bistability and oscillations in gene regulation mediated by small noncoding RNAs.

The interplay of small noncoding RNAs (sRNAs), mRNAs, and proteins has been shown to play crucial roles in almost all cellular processes. As key post-transcriptional regulators of gene expression, the mechanisms and roles of sRNAs in various cellular processes still need to be fully understood. When participating in cellular processes, sRNAs mainly mediate mRNA degradation or translational repression. Here, we show how the dynamics of two minimal architectures is drastically affected by these two mechanisms. A comparison is also given to reveal the implication of the fundamental differences. This study may help us to analyze complex networks assembled by simple modules more easily. A better knowledge of the sRNA-mediated motifs is also of interest for bio-engineering and artificial control.

[A preliminary study on preservation methods of Blastocystis hominis].

OBJECTIVE: To observe the effect of different cryoprotective agents and temperature factors on the viability of Blastocystis hominis so as to explore the ideal method for preservation of B. hominis. METHODS: B. hominis agents were obtained from a patient's fecal specimen. Having washed by normal saline and divided into tubes, the samples were cryopreserved in -20 degrees C refrigerator or in -196 degrees C liquid nitrogen with 10% DMSO, 40% glycerol and 15% ethylene glycol respectively. The thawed B. hominis agents were then used for culture. By trypan blue staining and microscopy, the viability and proliferation of those resuscitative cells were investigated. RESULTS: B. hominis survived for 3 weeks at 18 degrees C-20 degrees C while less than 1 week at 4 degrees C-6 degrees C. When stored in -20 degrees C refrigerator or liquid nitrogen with cryoprotective agents, they survived for more than 3 months. The cryopreservation with 40% glycerol at -196 degrees C for 6 months resulted in 41.7% viability of the revivified cells. Cleavage cells were easily observed after culturing for 72 hours. CONCLUSION: Preserving B. hominis in liquid nitrogen with 40% glycerol is an optimal cryopreservation protocol.