Scanning electron microscopic observation of morphology of Rhipicephalus sanguineus at different developmental stages in Hainan Province / 中国热带医学

@#Abstract: Objective To understand the morphological characteristics and ultrastructure of the dominant species of Rhipicephalus sanguineus in Hainan at different developmental stages, and provide theoretical basis for the identification of the lineage and control of Rhipicephalus sanguineus. Methods The external morphology of different developmental stages of the dominant species of Rhipicephalus sanguineus, including larva, nymph and adult tick in Hainan were observed by scanning electron microscope. Results The division between each segment of larva pedipalps was not obvious, and setae was serrated; dental formula type 2 | 2; 3 pairs of podomere; a pair of setae on the anal valve; none of anal groove, spiracular plate, porous area and genital aperture. There was a clear boundary at the beginning of each segment of nymph pedipalps; dental formula type 2 | 2; 4 pairs of podomere; 3 pairs of setae on the anal valve; anal groove; none of porous area and genital aperture. The male adult tick's trichotheca are covered by the pedipalps, and the whole bristles are conical; dental formula type 3 | 3; 4 pairs of podomere; anal groove and paraprocts; 7 setae on the anal valve; genital aperture was oval. The female of adult tick can be distinguished by dental formula 3 | 3; pairs of podomere; porous areas with 3 short setae; anal groove; 4 pairs of setae and 2 pores on the anal valve; genital pore was broadly U-shaped. In addition, the male adult's scutum occupies almost the entire dorsal surface, the basis capituli of larva, nymph and adult tick all were hexagonal, and the existence of Haller's organ was found on the first pair of legs. Conclusions Scanning electron microscopy observation of the different developmental stages of R.sanguineus revealed clear morphological features, preliminarily suggesting that R.sanguineus in Hainan Province may belong to the tropical lineage, which provide a certain experimental basis for the identification of the tick and the comprehensive prevention and control of local tick-borne diseases.

Phytoplankton community and HAB species in the South China Sea detected by morphological and metabarcoding approaches.

The southern Chinese coast is one of the most developed regions in China and is an area where harmful algal blooms (HABs) have occurred frequently. In this study, differences in the phytoplankton community between microscopic observations and 18S rDNA metabarcoding were compared in 89 surface water samples collected from the southern Chinese coast and the western South China Sea (SCS). This is the first report investigating the phytoplankton community and HAB species using a combination of morphological and metabarcoding approaches in this sea area. There were substantial differences in phytoplankton community structure detected by the two methods. Microscopic observation revealed diatom predominance in the phytoplankton community, while metabarcoding indicated dinoflagellate dominance. The phytoplankton community structure obtained by microscopic observation better reflects the real situation in the water column. Metabarcoding annotated more species than morphospecies observed by microscopy. Haptophyta and Cryptophyta were the specific phyla detected in metabarcoding but were missed in microscopy due to their small size. Conversely, some taxa were found in microscopic analysis alone, such as species in Dinophysis, Prorocentrum, and Scrippsiella, suggesting some biases during metabarcoding and gaps in sequence databases. Metabarcoding is superior for detecting morphologically cryptic, small-sized and HAB taxa, such as unarmored dinoflagellates, nanosized hatophytes and chlorophytes, as well as multiple species in Alexandrium, Pseudonitzschia, and Chaetoceros in our study. A total of 62 HAB taxa were identified in this study, including blooming and potentially toxic species. Diatom abundances generally decreased southward, while those of dinoflagellates and haptophytes showed the opposite trend. Chlorophytes were mainly distributed in coastal waters, especially in the Pearl River Estuary. Phytoplankton community structures were shaped by nutrients and salinity, and phosphorus was the most limiting factor for phytoplankton growth. The phytoplankton community in the western SCS showed unique characteristics away from those in the coastal sea areas. The results suggest that the combination of morphological and metabarcoding approaches comprehensively reveals the phytoplankton community structure and diversity of HAB species.

Effect of Silkworm Pupa Protein Hydrolysates on Proliferation of Gastric Cancer Cells In Vitro.

The proliferation inhibition effects of the hydrolysates from silkworm pupa proteins on MGC-803 gastric cancer cells were investigated in this study. The specific morphological changes (cell membrane, cell nucleus and cytoskeleton) of cells were measured. In vitro, the proliferation of MGC-803 cells was inhibited by silkworm pupa protein hydrolysates (SPPHs) in a dose-dependent manner. The flow cytometry analysis showed that the blocking effect of SPPHs on the MGC-803 cells was mainly in the G0/G1-phase. The morphological changes, disintegration of the cytoskeleton and retardant cell cycles were probably related to the activation of apoptosis. Thus, SPPHs could be promising as a chemopreventive agent due to their ability to promote apoptosis of tumor cells.

Evidence for mixotrophy in pico-chlorophytes from a new Picochlorum (Trebouxiophyceae) strain.

Mixotrophs are increasingly recognized for their wide distribution in aquatic ecosystems and significant contributions to biogeochemical cycling. Many taxa within the phyla Chrysophyta, Cryptophyta, and Haptophyta are capable of phago-mixotrophy, however, phagotrophy in the Chlorophyta remains controversial due to insufficient research and solid evidence. In this study, we identified a new strain, Picochlorum sp. GLMF1 (Trebouxiophyceae), using 18S rRNA gene analysis and morphological observations. It displayed multi-cell division through autosporulation (two- or four-cell daughters) and has two unequal flagella that have never been reported in the genus Picochlorum. By using multiple methods, including 3D bioimaging analysis, acidic food vacuole-like compartment staining, and prey reduction calculation, we discovered and confirmed bacterivory in Picochlorum, which provided strong evidence for phago-mixotrophy in this green alga. In addition, we found that Picochlorum sp. GLMF1 cannot grow under complete darkness or prey-depleted conditions, suggesting that both light and bacteria are indispensable for this strain, and its mixotrophic nutrition mode is obligate. Like other phago-phototrophs, Picochlorum sp. GLMF1 is capable of regulating their growth and ingestion rates according to light intensity and inorganic nutrient concentration. The confirmation of mixotrophy in this Picochlorum strain advances our understanding of the trophic roles of green algae, as well as the photosynthetic picoeukaryotes, in marine microbial food webs.

Cellular Analysis and Comparative Transcriptomics Reveal the Tolerance Mechanisms of Candida tropicalis Toward Phenol.

Phenol is a ubiquitous pollutant and can contaminate natural water resources. Hence, the removal of phenol from wastewater is of significant importance. A series of biological methods were used to remove phenol based on the natural ability of microorganisms to degrade phenol, but the tolerance mechanism of phenol-degraded strains to phenol are not very clear. Morphological observation on Candida tropicalis showed that phenol caused the reactive oxygen species (ROS) accumulation, damaging the mitochondrial and the endoplasmic reticulum. On the basis of transcriptome data and cell wall susceptibility analysis, it was found that C. tropicalis prevented phenol-caused cell damage through improvement of cell wall resistance, maintenance of high-fidelity DNA replication, intracellular protein homeostasis, organelle integrity, and kept the intracellular phenol concentration at a low level through cell-wall remodeling and removal of excess phenol via MDR/MXR transporters. The knowledge obtained will promote the genetic modification of yeast strains in general to tolerate the high concentrations of phenol and improve their efficiency of phenol degradation.

Combination Susceptibility Testing of Common Antimicrobials in Vitro and the Effects of Sub-MIC of Antimicrobials on Staphylococcus aureus Biofilm Formation.

The current study was conducted to evaluate the antibacterial combination efficacies, and whether the sub-inhibitory concentrations (sub-MIC) of antibiotics can influent on the biofilm formation of S. aureus. The minimum inhibitory concentration (MIC) of common antibacterial drugs was determined in vitro against clinical isolates of Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Pasteurella multocida (P. multocida) alone and in combination with each other by using the broth microdilution method and the checkerboard micro-dilution method analyzed with the fractional inhibitory concentration index (FICI), respectively. Regarding these results, antibacterial drug combinations were categorized as synergistic, interacting, antagonistic and indifferent, and most of the results were consistent with the previous reports. Additionally, the effects of sub-MIC of seven antimicrobials (kanamycin, acetylisovaleryltylosin tartrate, enrofloxacin, lincomycin, colistin sulfate, berberine, and clarithromycin) on S. aureus biofilm formation were determined via crystal violet staining, scanning electron microscopy (SEM) and real-time PCR. Our results demonstrate that all antibiotics, except acetylisovaleryltylosin tartrate, effectively reduced the S. aureus biofilm formation. In addition, real-time reverse transcriptase PCR was used to analyze the relative expression levels of S. aureus biofilm-related genes such as sarA, fnbA, rbf, lrgA, cidA, and eno after the treatment at sub-MIC with all of the six antimicrobials. All antibiotics significantly inhibited the expression of these biofilm-related genes except for acetylisovaleryltylosin tartrate, which efficiently up-regulated these transcripts. These results provide the theoretical parameters for the selection of effective antimicrobial combinations in clinical therapy and demonstrate how to correctly use antibiotics at sub-MIC as preventive drugs.

Improvement of docosahexaenoic acid fermentation from Schizochytrium sp. AB-610 by staged pH control based on cell morphological changes.

Schizochytrium sp. AB-610 accumulates relatively higher amount of DHA-rich lipid in the cells, and it was found that DHA yield was closely related to the cell morphology and pH value during fermentation period. DHA production from Schizochytrium sp. AB-610 in fed-batch fermentation was investigated and four growth stages were clarified as lag stage, balanced growth stage, lipid accumulation stage, and lipid turnover stage, based on the morphologic observation and key parameters changes. Then a simple strategy of two-stage pH control was developed, in which pH 7.0 was kept until 12 h after the end of balanced growth stage, and then shifted to 5.0 for the rest period in fermentation. A maximal DHA production of 11.44g/L was achieved. This approach has advantage of easy scaling up for industrial DHA fermentation from Schizochytrium sp. cells.

[Investigation on Cheyletoidea mites breeding in culture environment of Eupolyphaga sinensis and morphologic observation of Eucheyletia reticulate Cunliffe].

OBJECTIVE: To investigate the species of Cheyletoidea mites breeding in the culture environment of Eupolyphaga sinensis and to observe the morphology of Eucheyletia reticulata Cunliffe. METHODS: The soil samples from an E. sinensis farm in northern Anhui were collected. The mites in the soil samples were separated directly under a microscope and the glass specimens were made to observe the morphological feature of the mites under a light microscope, then the mites species were identified and classified based on the morphological characteristics. RESULTS: In the culture soil of E. sinensis, totally 7 kinds of Cheyletoidea mites were isolated, namely Eucheyletia reticulata Cunliffe, Cheyletus eruditus Schrank, Cheyletus malaccensis Oudemans, Cheyletus troussarti Oudemans, Cheyletus aveisor Rohdendorz, Acaropsis sollers Rohdendorz and Cheletomorpha lepidopterorum Shaw. They belonged to genera Eucheyletia, Cheletomorpha, Acaropsis and Cheyletus of Cheyletidae Leach family. The Eucheyletia reticulata Cunliffe was firstly found in the culture environment of E. sinensis, and its gnathosoma was large, the pedipalpal femurs were expanding and there were two strips of comb hair and two smooth bristles on the pedipalpal tarsus, and the back of the body was covered with two pieces of tergum, which were decorated with reticular pattern. The body and foot setae were fan-shape. CONCLUSIONS: There are various of Cheyletoidea mites found in the breeding environment of E. sinensis. These mites are important species for pest control in the culture environments of E. sinensis. Related measures should be taken to prevent the excessive growth of Cheyletoidea mites, so as to avoid the adverse effects on the quality and quantity of E. sinensis.

Investigation on Cheyletoidea mites breeding in culture environment of Eupolyphaga sinensis and morphologic observation of Eucheyletia reticulata Cunliffe / 中国血吸虫病防治杂志

Objective To investigate the species of Cheyletoidea mites breeding in the culture environment of Eupolyphaga sinensis and to observe the morphology of Eucheyletia reticulata Cunliffe. Methods The soil samples from an E. sinensis farm in northern Anhui were collected. The mites in the soil samples were separated directly under a microscope and the glass speci?mens were made to observe the morphological feature of the mites under a light microscope,then the mites species were identi?fied and classified based on the morphological characteristics. Results In the culture soil of E. sinensis,totally 7 kinds of Chey?letoidea mites were isolated,namely Eucheyletia reticulata Cunliffe,Cheyletus eruditus Schrank,Cheyletus malaccensis Oudemans,Cheyletus troussarti Oudemans,Cheyletus aveisor Rohdendorz,Acaropsis sollers Rohdendorz and Cheletomor?pha lepidopterorum Shaw. They belonged to genera Eucheyletia,Cheletomorpha,Acaropsis and Cheyletus of Cheyletidae Leach family. The Eucheyletia reticulata Cunliffe was firstly found in the culture environment of E. sinensis,and its gnathosoma was large,the pedipalpal femurs were expanding and there were two strips of comb hair and two smooth bristles on the pedipal?pal tarsus,and the back of the body was covered with two pieces of tergum,which were decorated with reticular pattern. The body and foot setae were fan?shape. Conclusions There are various of Cheyletoidea mites found in the breeding environment of E. sinensis. These mites are important species for pest control in the culture environments of E. sinensis. Related measures should be taken to prevent the excessive growth of Cheyletoidea mites,so as to avoid the adverse effects on the quality and quan?tity of E. sinensis.

Morphological observation of Tritrichomonas muris isolated from Xinjiang Cricetulus migratorius and analysis of its 16 S rRNA gene / 中国实验动物学报

Objective To conduct morphological observation and gene identification of the strain of flagellate iso -lated from Cricetulus migratorius in the Xinjiang Research Center for Experimental Animals .Methods The ileocecal con-tents of C.migratorius were microscopically examined on direct smear with Wright-Giemsa staining , and the total RNA iso-lated from Xinjiang C.migratorius was extracted and 16S rRNA was amplified by PCR , and then sequenced .Furthermore the homology was compared and the phylogenetic tree was developed using MEGA 5.22 software.Results Morphological observation indicated that the isolated flagellate was Tritrichomonas muris.The 16S rRNA gene sequence of the Xinjiang C. migratorius isolate shared highly homology with that of other Tritrichomonas.Phylogenetic tree analysis indicated that the 16S rRNA gene of Xinjiang C.migratorius isolate was classified into a subgroup with T.muris 16S rRNA (U85966.1), but was relatively distant relative from other related tritrichomonas.Conclusions The flagellate isolated from Xinjiang C. migratorius is identified to be T.muris by both morphological observation and 16S rRNA gene analysis.

Observation of the preparation and morphology of the small intestinal submucosa sponge / 中国基层医药

Objective The sponge of the small intestinal submucosa(SSIS) is established by the material chemistry,in order to supply the database for the scaffold of the dermic tissue engineering.Methods At the regular temperature,the SSIS was conducted firstly by the physiochemical method.Then,the SSIS was crosslinked by the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) so as to get the three dimentional SSIS.The morphological feature was obtained by the lighting and electron microscope,ophthalmic oberservation,the embedding in the mouse of the SSIS was used to observe the adsorbing and immunology.The results were analyzed by statistic software.Results The crosslinked SSIS was regular in the structure and not loosen,the framework was equilibrium,the pore was abundant with the diameter of the 100 ～ 200μm,the difference was obvious (all P ＜ 0.05).The firstweek after embedding did not exist the adherence leukocyte infiltration,the vascularization occur in the third week.The material was completed and had no elastic degradation.Conclusion Reconstructed SSIS has completed structure,elastic with the vascularization and minor immunology,which could be used as the extracellular scaffold for the dermic tissue engineering.

Histological and ultrastructural alterations of liver graft undergoing warm ischemia injury from non-heart-beating donor in rats / 中国普通外科杂志

Objective To investigate the histological and ultrastructural characteristics of liver graft after different warm ischemia time (WIT) in rats. Methods According to WIT, rats were randomized into 7 groups, with WIT of 0, 10, 15, 20, 30, 45, 60 minutes respectively. All specimens were investigated by light, electron microscopy, and histochemistry stain. 6, 24, and 48 hours after orthotopic liver transplantation(OLTx) ,the graft morphology was observed. Results The donor liver from non-heart-beating donors (NHBO) underwent ischemia injury both in the warm ischemia period and in the reperfusion period. Morphological changes were positively related to warm ischemia time in a time-dependent manner during the reperfusion period. There was a histocytic degeneration of different degree within 30 minutes warm ischemia. Although becoming more severe with the prolongation of warm ischemia time within this period, there was no obvious hepatocyte necrosis in any specimens. In WIT 45 min group, small focal necrosis occurred which was found in central area of hepatic lobule first. In 60 min group, patchy or diffused necrosis was observed and the area was gradually extended, while hepatic sinusoid endothelial cell obviously swelled to be bleb or balloonlike, hepatic sinusoid was obstructed and microcirculation was in disorder. Conclusion Rat liver graft undergoing warm ischemia injury is on the reversible stage within 30 minutes warm ischemia time by histological, histochemistry and ultrastructural dynamic observation. 45 min is a critical point of rat liver graft to endure warm ischemia injury, and when WIT was over 60 min, the damage is irreversible.

Morphological observation of Ascending Pharyngeal Artery and Ascending Palatine Artery / 昆明医科大学学报

A detailed description of the ascending pharyngeal artery and the ascending palatine artery,including their courses,branches and supplies,was given based on the full dissection,exposure and comparison of 30 sides of half-head specimens(20 sides of fetus heads and 10 sides of adult heads).The results are as follows:(1) the arteries can be divided into three types,the dominant type of the ascending pharyngeaL artery,the dominant type of the ascending palatine artery and the type of balance;(2)the various branches of the ascending pharyngeal artery,especia- lly some branches unknown or known a little,have been described in detail;(3) recommendation of a simple and rapid method for exposing these two arteries.

MORPHOLOGICAL OBSERVATION OF EFFECTS OF ELECTROACUPUNCTURE ON BRAIN INFARCT RAT / 解剖学报

0.05) 1 day after acupuncture.There was a significant difference in the damage neurons of penumbrazone between the acupuncture and control groups(P