Tail Research Articles

Study on the characteristics of pharmacokinetics of different doses of gastrodin in mice

Background: Rhizoma Gastrodiae, the dried rhizome of Gastrodia elata Blume (G. elata) , is famous Chinese herb that belongs to the genus Gastrodia , family Orchidaceae. Gastrodin (GAS) is an effective monomer with one of the major active constituents in Rhizoma Gastrodiae . GAS has a good sedative and sleeping effect and has a mitigating effect on neurasthenia, insomnia, and headache. Moreover, in the circulatory system, it has the effect of reducing peripheral vascular resistance, blood pressure, and so on. Objectives: The objective is to investigate the pharmacokinetic characteristics after the administration of different doses of GAS by using pharmacokinetic method and make a preliminary judgment on whether the intake of GAS in the liver is involved in transporters. Materials and Methods: All healthy mice were randomly divided into three groups according to the drug concentration: low-concentration group (LC group), middle-concentration group, and high-concentration group. Then, each group received different doses of GAS by tail vein injection. The blood samples of different groups were harvested at different time points, and the blood drug concentration was evaluated by high-performance liquid chromatography method. The method was confirmed in terms of the linearity, precision, and accuracy. Results: The results showed that the analytical curve was linear over the concentration range of 4–40 μg/mL. In the intra- and inter-assay, the coefficient of variation was

Screening of potential inhibitors against flotillin-1 as therapeutics for Alzheimer's disease

Background: Alzheimer's disease (AD) is one of the most common neurological disorders occurring in older people. So far, no specific drug is available for the disease, and only palliative medicines are available for the patients. Accumulation of amyloid beta (Aβ) peptides is considered to play a crucial role in the generation of the disease. Aβ peptide is generated by the proteolysis of amyloid precursor protein by two distinct proteases β and γ-secretase. Flotillin-1 (FLOT1) directly binds to the cytoplasmic tail of β-secretase and affects the sorting and recycling of the enzyme. Increased expression of FLOT1 has been correlated with the progression of AD, while FLOT1 knockdown causes a reduction in Aβ production. Thus, FLOT1 is an attractive therapeutic target for the suppression of beta-secretase 1 (BACE-1 ). Objective: This study aims to screen the potential inhibitors against FLOT1 as therapeutics for AD. Materials and Methodology: In this work, protein–protein interactions, tertiary structure prediction, molecular docking, and molecular dynamics (MD) simulation were performed. Results: Tertiary structure prediction of FLOT1 and screening inhibitors against it helped in finding key molecules with potential therapeutic properties. Protein–protein interaction study of FLOT1 deciphered the interactors playing key role in AD. Pharmacokinetic parameters were quantified for each potential inhibitor. The results of MD simulation analysis revealed that the ZINC67911837 had better inhibitory activities with FLOT1. Conclusion: The analysis suggests that the ZINC67911837 compound could be a novel potential inhibitor of FLOT1 to modulate BACE-1 activity and used as a therapeutic agent for the treatment of AD. This study facilitates the initiation of the natural drug discovery process for the treatment of AD patients.

The role and mechanism of myeloid-derived suppressor cells in mice with nonalcoholic steatohepatitis

Objective To investigate the effects of myeloid-derived suppressor cells (MDSCs) on nonalcoholic steatohepatitis mice. Methods ⑴ Male C57BL/6 mice aged 6-8 weeks were randomly divided into normal diet group, CDAA group(choline deficient amino acid diet) and CSAA group (choline sufficient amino acid diet). ⑵ After the success of the non-alcoholic steatohepatitis model, serum was collected from some mice to detect biochemical indexes; Liver tissue was retained for microscopic observation by hematoxylin-eosin (HE) staining; The changes of T cell subsets in peripheral blood of mice in each group were detected by flow cytometry. In addition, The proportion and subtype of CD11b+ Gr-1+ MDSCs cells in liver, spleen, blood and bone marrow were also detected by flow cytometry. ⑶ The bone marrow-derived Gr-1highLy-6G+ was purified by magnetic bead sorting technique, and the purified Gr-1highLy-6G+ was transferred into non-alcoholic steatohepatitis (NASH) mice by tail vein injection. The role of MDSCs in NASH was analyzed by detection of serological indexes of liver function and pathological dyeing. Results ⑴ There was no significant difference in body weight and liver index between the groups (P>0.05). Serological indicators: alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood glucose, interleukin (IL)-6 and interferon-γ (INF-γ) in the model group were significantly higher than those in the normal group (P 0.05); the MDSCs of liver in CDAA group is lower than that of normal group (P normal group (P<0.01), CD11b+ Gr-1dimLy-6G-(M-MDSC) showed a downward trend, CDAA group < normal group; ⑶ Serum AST and ALT levels of NASH mice who receiving Gr-1highLy-6G+ MDSCs from normal bone marrow were significantly decreased (P<0.001), and histopathological changes were alleviated. Conclusions ⑴ The NASA mouse model can be successfully established on the CDAA diet. ⑵ The CDAA-induced NASH mice may have immune dysfunction, mainly manifesting in the change of bone marrow MDSCs subpopulations and the increase of CD11b+ Gr-1highLy-6G+ (G-MDSC). ⑶ MDSCs derived from normal mouse bone marrow can alleviate the pathological changes of NASH. Key words: Myeloid-derived suppressor cells; Non-alcoholic steatohepatitis; T-lymphocytes; Interleukin-6; Mice

Effects of stress preconditioning on vulnerability of gastric and small intestinal mucosa to ulcerogenic action of indomethacin in rats.

The preconditioning effect of a mild stressor can reduce the ulcerogenic effect of a severe stressor on the gastric mucosa. The aim of the study was to investigate the effect of preconditioning stress on the gastric and the small intestinal injury caused by a single injection of indomethacin (IM) in conscious rats. Preliminary fasting (24 hours) rats were subjected IM administration (35 mg/kg, subcutaneously) with preconditioning stress (30 min cold-restraint at 10°C and further 1 hour keeping in cages at room temperature) or without stress. Plasma corticosterone level, heart rate (HR), blood pressure (BP) and somatic pain sensitivity (tail flick latency) were measured under circumstances of the gastrointestinal IM-induced injury in preliminary stressed and non-stressed rats. IM administration induced formation of gastric erosions well visible 4 hours after its injection. The healing of gastric erosions for 48 hours was accompanied by the development of a small intestinal injury. Corticosterone levels were elevated under formation of gastric erosions (4 hours after IM injection) but decreased following their healing (24 and 48 hours IM injection). Cold-restraint stress caused corticosterone rise 30 min after its onset. IM-induced gastrointestinal injury resulted in an increase of tail flick latencies (somatic hypoalgesia) and gradual decrease of systolic BP and increase of the HR. Stress preconditioning attenuated IM-induced gastric erosions as well as small intestinal injury 4 and 24 hours after its injection, respectively. The preconditioning also resulted in elimination of somatic hypoalgesia 4 hours after IM, but didn't influence an appearance of somatic hypoalgesia 24 and 48 hours after IM. Preconditioning stress recovered the HR and systolic BP (48 hours after IM). Elevated corticosterone level could be observed only in the 4th hour, but not in the 24th and 48th hours after IM administration. Thus, the data suggest that preconditioning stress reduces the vulnerability of the gastric and the small intestinal mucosa to ulcerogenic action of IM, stabilizes the hemodynamic parameters and normalizes somatic pain sensitivity.

A New Species of Triumphalisnema (Nematoda: Coronostomatoidea) Parasite of Proculejus hirtus (Coleoptera: Passalidae) from Mexico, and the Position of the Family in the Oxyuridomorpha

A new species of the nematode Triumphalisnema Kloss, 1962 (Oxyuridomorpha), is described from the wood beetle Proculejus hirtus Truqui from the mountain mesophilic forest in Hidalgo State, Mexico. Triumphalisnema zuuei n. sp. is distinguished from the other 4 congeners species by the presence of an expanded cervical ring, well-developed lateral alae, an obtuse cauda with a short and bifurcated caudal appendage, series of cuticular folds at ventral and dorsal body surface from excretory pore level to anal region, and ellipsoidal eggs ornamented with numerous small mushroom-like structures over the surface. The phylogenetic position of the new species is inferred based on a Maximum Likelihood and Bayesian Inference analysis of partial sequences of 18S SSU rRNA. The phylogenetic analysis showed that Triumphalisnema zuuei n. sp., the only representative of the Traklosiidae in our study, is closely related to Coynema poeyi and species of Longior, Hystrignathus, and Lepidonema, all of them members of Hystrignathidae. These relationships are supported by high support values. The present study increases to 5 the number of species assigned to Triumphalisnema, all of them parasites of Passalidae. Additionally, a taxonomic key to the species of the genus is provided.

Effects of Human Amniotic Mesenchymal Stem Cells on Acute Graft-Versus-Host Disease in Xenotransplantation

To investigate the effects of human amniotic mesenchymal stem cell（AMSC） on acute graft-versus-host disease (aGVHD) in xenotransplatation. NPG mice were injected with human PBMNC via tail vein to establish a xenografted aGVHD model. The mice in the experimental group were divided into PBMNC infusion group and PBMNC+AMSC co-infusion group, the general condition, survival time and manifestations of aGVHD were observed, the body weight and blood routine indicators were detected, the pathological changes of aGVHD target organs (lung, liver, spleen, small intestine) were observed by HE staining, and the levels of human T cells in peripheral blood, tissues and organs of mice was detected by flow cytometry. The manifestations of aGVHD (lassitude hunchback, shrub, weight reduction, etc.) and the pathological damage of the target organs (lung, liver, spleen, intestine) in PBMNC+AMSC co-infusion group were lighter than those in PBMNC infusion group. Moreover, the PBMNC and AMSC co-infusion significantly reduced the implantion proportion of human T lymphocytes (CD3+, CD45+) in mice and increased the ratio of CD4+/CD8+. Infusion of human-derived AMSC can attenuate the manifestations of aGVHD in mouse xenografts to a certain level, and improve the pathological damage of receptor target organs.

Long noncoding RNA GAS5 enhanced by curcumin relieves poststroke depression by targeting miR-10b/BDNF in rats.

The treatment for post-stroke depression (PSD) is mainly based on a therapeutic strategy combining anti-stroke and anti-depressant drugs. In the present study, the therapeutic effect of curcumin on rats with PSD was detected by open field tests and tail suspension tests, as well as the examination of corticosterone and corticotropin-releasing hormone (CRH) levels in the serum and neurotransmitter 5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and dopamine (DA) levels in the hippocampus. Curcumin notably alleviated depression compared to the controls. Furthermore, long noncoding RNA growth arrest-specific transcript 5 (GAS5) enhanced by curcumin contributed to activation of the BDNF/Trkβ signaling pathway to promote the expression of synaptic-related proteins. GAS5 was demonstrated to function as a sponge of miR-10b. GAS5 upregulation by curcumin could reduce miR-10b to compromise the BDNF mRNA levels. Taken together, these results revealed a novel mechanism of curcumin on PSD through the GAS5/miR-10b/BDNF regulatory axis.

BAX Deletion Accelerates Progression of BCR-ABL-Induced B-ALL in Mice

To explore whether BAX plays a role in the development of Philadelphia chromosome-positive leukemia and related mechanisms. Target-gene knockout mice were used as bone marrow cell donors. Retrovirus over-expressing BCR-ABL were packaged. BCR-ABL-induced B-ALL mouse model was established through donor's B cells transfected by the retrovirus and the B cells over-expressing BCR-ABL were given to the receptor mice by tail vein injection. Western blot was used to detect the protein express and flow cytometry was used to analyze the B cell subpopulations in BAX-/- and WT mouse bone marrows. Kaplan-Meier analysis was used to estimate the survival of diseased mice. BAX deletion caused faster development of BCR-ABL-induced leukemia in vitro and in vivo. BCR-ABL increased BCL-2 expression and enhanced BCL-2/BAX heterodimer formation. The BAX deletion can accelerate the disease progression of BCR-ABL induced B-ALL.

A rare bird of Czechia: Case of homozygous female Fabry disease patient

A new myxozoan species belonging to the genus Henneguya was isolated from the serous membrane of the visceral cavity of the hognosed catfish Brochis multiradiatus from Peruvian Amazon. Whitish plasmodia, macroscopically visible, were found in four of the thirty examined fishes. Mature myxospores were ellipsoidal in shape in frontal view and had a total length of 44.5 ± 0.6 μm (43.9–45.1), spore body measured 18.7 ± 0.9 μm (16.8–19.6) in length, 7.1 ± 0.2 μm (6.6–7.4) in width and 5.5 ± 0.3 μm (4.9–5.6) in thickness. The two polar capsules were elongated and equal in size, measuring 9.1 ± 0.1 μm (8.8–9.4) in length and 1.7 ± 0.1 μm (1.6–1.8) in width, occupying half of the myxospore body. Polar tubules coiled in 10–11 turns perpendicular to the long axis of the polar capsule. The caudal appendage was not bifurcated and measured 25.8 ± 0.6 μm (24.7–26.5) in length. The sequencing of the 18S rDNA gene resulted in 1400 bp and this sequence did not match any of the myxozoans available in GenBank. Phylogenetic analysis placed the new species in a well-supported subclade of Henneguya spp. infecting callichthyid fishes, with Henneguya loretoensis being the closest species. This study is the first description of a myxozoan species, Henneguya multiradiatus n. sp. from a fish of the genus Brochis.

COMPROMISO ORGANIZACIONAL Y PRODUCTIVIDAD DE LOS TRABAJADORES EN PROTEGE ORIENTE S.A., PUCALLPA, 2019

El objetivo del estudio es determinar el grado deasociación existente entre el compromiso organizacionaly productividad de los colaboradores en Protege OrienteS.A., Pucallpa, 2019, las dimensiones e indicadores de lavariable: el compromiso organizacional, fueron adaptadosdel trabajo de Fuentes (2018), de la misma manera loselementos de la variable: productividad de los trabajadores,se adaptaron de Zapata (2018). El tipo de investigaciónfue aplicativo, el nivel descriptivo correlacional, la muestraestuvo compuesta por el total de la población, 54 personas,que trabajaron en la empresa de vigilancia privada, ProtegeOriente SA, Pucallpa. Mediante la prueba de hipótesis,unilateral de cola derecha, utilizándose el coeficiente rhode Spearman se determinó que existe relación directay significativa entre el compromiso organizacional yproductividad de los trabajadores en Protege Oriente S.A.,con la correlación de 0,794, estimada como asociaciónpositiva considerable, en tanto que el nivel de significanciade la prueba, tuvo un valor: s = 0.000 ˂ 0.05, el coeficientefue significativo en el nivel de 0.000, en consecuenciael nivel de confiabilidad es100 % que la correlación seaverdadera y 0.0 % de probabilidad de error

Effect and mechanism of DL-3-n-butylphthalide on emotional memory in mice with chronic alcoholism

Objective To investigate the improvement and possible mechanism of dl-3-n-butylphthalide (NBP) on the emotional memory of chronic alcoholism model mice. Methods Twenty-four adult male C57/BL6 mice were randomly divided into control group (CON, n=8), model group (AT, n=8), treatment group (AT+ NBP, n=8). Mice in AT group and AT+ NBP group were administrated with alcohol to establish chronic alcoholism model. In the AT+ NBP group, the mice was administrated with NBP (40 mg/kg) by gavage once a day for 14 days during the alcohol modeling period. Ang the mice in AT group and CON group was given the same dose of corn oil by gavage.Open field test was used to evaluate anxiety-like behavior, tail suspension test to evaluate depression-like behavior, Morris water maze and new object recognition to evaluate memory ability, and TUNEL staining to evaluate the number of neuron apoptosis. The primary cultured neurons were interfered by alcohol and NBP at the cell level, and the calcium concentration in the neurons was detected by fluorescence calcium imaging. Descriptive analysis, t-test and one-way ANOVA were processed by SPSS 17.0. Results The results of open field test showed that the exploration time of AT+ NBP group was longer than that of AT group ((50.68±7.82)s, (38.50±13.93)s; t=-2.16, P<0.05)). In the spatial memory test, the target quadrant exploration time of AT+ NBP group was longer than that of AT group ((28.02±7.13)s, (20.98±5.58)s; t=-2.20, P<0.05). In short memory test, the cognitive coefficient RI (0.83±0.08) of AT+ NBP group was higher than that of AT group (0.68±0.10) (t=-3.13, P<0.05). Compared with CON group, the number of neuron apoptosis in prefrontal cortex in AT group increased ((17.33±2.51), (115.67±6.50); t=-24.41, P<0.001), and that in AT+ NBP group decreased compared with AT group((45.00±5.57)) (t=14.29, P<0.001). The number of apoptosis neurons in the dentate gyrus of the hippocampus in AT group (13.75±4.79) was also less than that in the AT+ NBP group (5.75±3.30) (t=2.75, P<0.05). Calcium concentration in nerve cells was detected that the three concentrations of alcohol (100 mmol/L, 200 mmol/L and 300 mmol/L) led to a significant increase in the RFU within the nerve cells (△F/F) ((1.43±0.32), (2.31±1.39), (1.21±0.73); t=-7.67, -2.85, -2.86, all P<0.05). In comparison, the changes of RFU in the three groups treated with NBP treatment were relatively stable ((0.04±0.01), (-0.03±0.01), (-0.04±0.02); t=7.96, 2.96, 2.92, all P< 0.05). Conclusion The 3-n-Butylphthalide can improve the learning and memory ability of chronic alcoholism model mice, which may be related with the inhibition of neuron apoptosis and the influence of intracellular calcium homeostasis. Key words: DL-3-n-Butylphthalide; Alcoholism; Anxiety; Memory; Neuronal apoptosis; Calcium homeostasis

Correlation between solute carrier transporter 22A3 gene rs7758229 polymorphism and prognosis of pancreatic cancer

Objective To investigate the relationship between solute carrier transporter 22A3 (SLC22A3) gene rs7758229 polymorphism and prognosis of pancreatic cancer. Methods One hundred patients with resectable pancreatic cancer who underwent surgery were admitted to our hospital from March 30, 2014 to March 30, 2016 were selected. There were were 61 male and 39 female patients, aging from 35 to 79 years with a median age of (49.1±5.7) years. The location included head and neck of the pancreas (n=66), body and tail of pancreas (n=34). According to the 7th American Joint Committee on Cancer (AJCC) Pancreatic Cancer Staging System, 19 cases were in stage I, 56 cases were in stage Ⅱ and 25 cases in stage Ⅲ. On the 2nd day after admission, 5 ml of fasting venous blood was taken, and the polymorphism of SLC22A3 gene rs7758229 was detected by DNA extraction kit and sequencing method. The patients were followed up and the end point was all-cause death. The correlation between polymorphism of rs7758229 and the prognosis of pancreatic cancer, and the factors affecting the overall survival (OS) of the patients were analyzed. The date analysis was conducted by SPSS 25.0; the gene type distribution deviation was tested by Hardy-Weinberg equilibrium, the correlation analysis of clinical date was analyzed by χ2 test analysis. The correlation between polymorphism of rs7758229 and the prognosis of pancreatic cancer, and the factors affecting the OS of the patients were analyzed by by Kaplan- Meier method and Cox model respectively. Results There were 28 cases (28.0%) of GG type, 51 cases (51.0%) of GT type, and 21 cases (21.0%) of TT type. The rs7758229 mononucleic acid polymorphism was significantly correlated with the degree of tumor differentiation and clinical stage (χ2=10.209, 10.826, P<0.05). Six patients were lost to follow-up (2 patients with GG, 3 patients with GT, and 1 patient with TT) with a median follow-up of 46 months. There were 73 deaths. Kaplan-Meier analysis and Log-rank test showed that overall survival (OS) was significantly shortened in patients with rs7758229 TT as compared with that in those with rs7758229 GG (Log-rank: χ2=11.254, P<0.05). Cox proportional hazard model results showed that rs7758229 mononuclear acid polymorphism [TT type/GG type, P<0.05, odds ratio (OR): 2.357, 95% confidence interval (CI): 1.524-6.317], TNM stage (P<0.05, OR: 1.194, 95%CI: 0.031-3.491), age (P<0.05, OR: 1.354, 95%CI: 1.067-4.357), degree of tumor differentiation (P<0.05, OR: 1.687, 95%CI: 1.108-4.217), and margin situation (P<0.05, OR: 1.947, 95%CI: 1.354-5.218) were independent prognostic factors influencing OS in patients with pancreatic cancer (P<0.05). Conclusion The rs7758229 polymorphism of SLC22A3 gene is associated with the survival rate of pancreatic cancer. The OS of TT patients is shorter. Key words: Solute carrier transporter 22A3 gene; Mononucleotide polymorphism; Pancreatic cancer; Overall survival

Extreme value modeling of structural load effects with non-identical distribution using clustering

The common practice to predict the characteristic structural load effects (LEs) in long reference periods is to employ the extreme value theory (EVT) for building limit distributions. However, most applications ignore that LEs are driven by multiple loading events and thus do not have the identical distribution, a prerequisite for EVT. In this study, we propose the composite extreme value modeling approach using clustering to (a) cluster initial blended samples into finite identical distributed subsamples using the finite mixture model, expectation-maximization algorithm, and the Akaike information criterion; (b) combine limit distributions of subsamples into a composite prediction equation using the generalized Pareto distribution based on a joint threshold. The proposed approach was validated both through numerical examples with known solutions and engineering applications of bridge traffic LEs on a long-span bridge. The results indicate that a joint threshold largely benefits the composite extreme value modeling, many appropriate tail approaching models can be used, and the equation form is simply the sum of the weighted models. In numerical examples, the proposed approach using clustering generated accurate extrema prediction of any reference period compared with the known solutions, whereas the common practice of employing EVT without clustering on the mixture data showed large deviations. Real-world bridge traffic LEs are driven by multi-events and present multipeak distributions, and the proposed approach is more capable of capturing the tendency of tailed LEs than the conventional approach. The proposed approach is expected to have wide applications to general problems such as samples that are driven by multiple events and that do not have the identical distribution.

Rhabdias elegans (Nematoda: Rhabdiasidae) in the toad, Rhinella arenarum (Hensel, 1867) from Argentina.

This study describes the morphology of Rhabdias elegans Gutierrez, 1945, isolated from the lungs of the toad Rhinella arenarum (Hensel, 1867) from Lomas de Tafi Tucumán, Argentina. This is the first record of R. elegans in R. arenarum from northwestern Argentina as previously described Rhabdias truncata is a species inquirendae. The distribution of R. elegans is extended since it was previously recorded in Buenos Aires, Chaco and Corrientes Provinces, Argentina. Our light microscopical study of morphological details of R. elegans revealed a few previously unreported structures in the apical region including position of the excretory pore and lateral sessile papillae in the tail. In addition, morphometric variability was observed on comparing present specimens and those described in previous studies. Our study made it possible to validate the occurrence of three Rhabdias species occurring in Argentina: R. elegans, R. füelleborni and R. cf. sphaerocephala. The information presented in this study represents an important contribution to the parasitological knowledge of R. arenarum from northwestern Argentina.

LC-ESI-MS/MS Alkaloidal Profiling and Biological Investigation of Cleistocactus winteri Stems.

Cleistocactus winteri is a succulent plant of the Cactaceae family, commonly known as the golden rat tail. Many members of the Cactaceae family are the focus of chemical and biological studies as they contain bioactive compounds, well known for their health-related properties. We aimed to investigate Cleistocactus winteri stems both phytochemically and biologically for the first time including three biological effects. For the evaluation of the anti-inflammatory activity, Nitric oxide (NO) inhibition on lipopolysaccharide (LPS) stimulated Raw murine microphages (RAW 264.7) cell model was used. The cytotoxic activity was evaluated against hepatocarcinoma (HepG2), breast adenocarcinoma (MCF-7), colorectal carcinoma (HCT-116), and colon adenocarcinoma (CACO 2) human cancer cell lines using MTT (3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide) assay. The antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Seven alkaloids were tentatively identified based on Mass bank on line library in addition to the isolation and identification of four known flavonoids and a β-sitosterol 3- O-glucoside from the studied extract. The stem methanol extract showed a 6% inhibition of NO production (up to 48 μmol/L). Furthermore, the IC50 of the total alkaloid fraction against HepG2, MCF-7, and CACO-2 cell lines was equal to 26.53, 23.8, and 13.07 µg/mL, respectively, while that of the methanol extract against Hep-G2 and HCT-116 was 181 µg/mL and 357 µg/mL, respectively with no effect against MCF-7 cell line. The antioxidant effect of the extract was about one third (112 µg/mL) that of ascorbic acid.

Description of three new species of Myxosporidia (Cnidaria: Myxobolidae) parasites of Paramormyrops kingsleyae Günther, 1896 (Mormyridae) in the Nyong basin in Cameroon

Parasitological examination of Paramormyrops kingsleyae Gunther, 1896 caught in the Djolon River in Cameroon revealed the presence of three new species of Myxosporidia of the genus Myxidium Butschli 1882 and Henneguya Thelohan, 1892 of which complete description is given in the present study. These species are: Myxidium binguelai sp. nov., parasite of the kidney that produce fusiform spores with a turgid medial part and both ends pointed. They measured 12.1 (11.1-12.9) μm long x 5.3 (4.8-5.8) μm broad; the polar capsules are ovoid, equal in size and measure 3.6 (3.0-4.1) μm x 2.5 (2.0-2.8) μm. Myxidium djolonensis sp. nov., a parasite of the gall bladder and urinary bladder, produce fusiform and elongated spores, that measure 16.3 (15.5-18.0) μm long x 6.1 (5-7.1) μm broad; its polar capsules are equal and measure 4.9 (4-5.6) x 3.5 (3-4.2) μm. Henneguya paramormyropsi sp. nov. form cyst in gill, eye and kidney. The total spore length is 29.2 (25.5-32.5) μm. The ovoid spore body, with narrowed anterior end measure 11.9 (10.7-12.8) μm x 4.5 (3.9-5.9) μm. The two separate caudal appendages measure 17.3 (14-20.3) μm. The 2 equal-sized thin and smooth valves surrounded 2 equal-sized pyriform, elongate polar capsules (5 (4.2-5.6) ×1.5 (1.2-1.9) μm) that contained 3 to 4 coils of the filament.

CARACTERIZAÇÃO TECNOLÓGICA E REAPROVEITAMENTO DE RESÍDUOS DE MAGNETITA EM MISTURAS ASFÁLTICAS E EM CONCRETO: UMA REVISÃO

A magnetita consiste em um mineral com excelentes propriedades magnéticas e mecânicas, estando presente em rejeitos da extração de ferro, estes, disponíveis mundialmente em milhões de toneladas depositadas em aterros. Ao considerar a variabilidade das características deste material, conforme especificidades da jazida de extração e das operações de processamento e reprocessamento, para a sua aplicação tecnológica é fundamental realizar a caracterização do resíduo. As mais promissoras formas de reaproveitamento do rejeito de magnetita referem-se a sua aplicação em asfalto e em concreto. Neste contexto, este trabalho aborda as principais técnicas de caracterização tecnológica de rejeitos de magnetita e suas contribuições, bem como resultados de estudos da incorporação do subproduto mineral em misturas betuminosas e concreto. Identificou-se que as técnicas utilizadas analisam os rejeitos e/ou material asfáltico compósito e betão considerando as propriedades físicas, químicas, mineralógicas e termodinâmicas. Verificou-se que o rejeito de magnetita, como substituinte parcial e integral do material de enchimento, melhorou a resistência à corrosão e às rachaduras das misturas asfálticas. Além disso, o uso de pó de magnetita, extraído do resíduo, melhorou a rigidez e a resposta elástica, bem como promoveu a cura de microfissuras da mistura betuminosa. A incorporação de resíduos do mineral em pó no concreto resultou em melhorias na trabalhabilidade e resistência do material. As informações desta revisão oferecem um panorama das técnicas de caracterização e das perspectivas de reciclagem dos rejeitos de magnetita no setor da construção civil.

Morphological variation of the newly confirmed population of the javelin sand boa, Eryx jaculus (Linnaeus, 1758) (Serpentes, erycidae) in Sicily, Italy

The presence of the Javelin sand boa in Sicily has recently been confirmed. Here the morphological characters and sexual dimorphism of the Sicilian population of Eryx jaculus are presented. Seven meristic and six metric characters in 96 specimens from Sicily were examined. The results show that tail length, snout-vent length, the distance between nostrils and the number of ventral and subcaudal scales are different between sexes. The characters found in the Sicilian population of the Javelin sand boa resemble those of the African population (ssp. jaculus) rather than the Eurasian population (ssp. turcicus), but biomolecular studies are necessary to understand its taxonomic identity.

Hot-Carrier Relaxation in CdSe/CdS Core/Shell Nanoplatelets

We present time-resolved photoluminescence (PL) spectroscopy of a series of colloidal CdSe/CdS core/shell nanoplatelets with different core and shell thicknesses. Exciton numbers are determined from the integrated PL intensities, and carrier temperatures are determined from the high-energy exponential tail of the PL spectra. For times between 10 and 1000 ps, the measured carrier relaxation dynamics are well described by a simple model of Auger reheating: biexcitonic Auger recombination continually increases the average energy of the carriers (while decreasing their number), and this reheating sets a bottleneck to cooling through electron–phonon coupling. For times between 1 and 10 ps, the relaxation dynamics are consistent with electron–phonon coupling, where the bottleneck is now the decay of the longitudinal optical phonon population. Comparison of relaxation dynamics to recombination dynamics reveals changes in the carrier–phonon coupling for shell thicknesses greater than 4 monolayers.

A whale of a tail

A whale of a tail