Initiation of the breeding season in ewe lambs and goat kids with melatonin implants

Sixty-eight female and 4 male lambs of the Chios breed born in autumn (September–October) and 48 female and 4 male kids of the Damascus breed also born in autumn (November), were used to evaluate the effect of melatonin implants (Regulin^®) on the initiation of the breeding season. For each species and sex, half of the animals were either left untreated to serve as controls (C) or received ear implants (females one and males two implants) of melatonin (MEL) in May (spring). Each C and MEL group of females was kept separately and away from males for 5 weeks after implantation and then, C and MEL males were joined with the respective groups for 45 (sheep) and 35 days (goats). Animals not conceiving during the early June–July breeding season, were mated again in September (natural breeding season). The reproductive performance and the 60-day milk yield of animals giving birth during the two seasons were compared. Early in the season (mid November–December), significantly more MEL than C ewes and goats gave birth (75.5% versus 23.5%, p < 0.01; 70.8% versus 37.5%, p < 0.05, respectively). For both species, most of the other characteristics examined were significantly affected by season, but not by treatment. Females giving birth early in the season were approximately 80 days younger at parturition and recorded a lower body weight at mating than those giving birth in the natural February–March season. In the first mating period, the animals mated and conceived had similar body weights to those not mated. The natural, compared with the early June–July mating season, was associated in sheep with higher litter weight at birth (7.0 kg versus 5.8 kg, p < 0.05) and in sheep and goats with a higher number (p < 0.05) of offspring born live (1.78 versus 1.38; 2.0 versus 1.61, respectively) and weaned (1.74 versus 1.36; 1.82 versus 1.35, respectively). Total litter size at birth and 60-day milk yield after weaning, were not significantly different between the two seasons. It could be concluded that melatonin implants administered during the last month of spring in autumn-born female Chios sheep and Damascus goats, advanced the initiation of their breeding season by about 80 days when joined with young males also treated with melatonin implants. The overall reproductive performance and milk yield of animals breeding early, was satisfactory and comparable to that of animals breeding in the natural breeding season.     

Salivary DNA,lipid, and protein oxidation in nonsmokers with periodontal disease

Reactive oxygen species (ROS) are implicated in the destruction of the periodontium during periodontitis. The imbalance in oxidant activity may be a key factor.The aim of this paper is to determine whether periodontitis is associated with increased oxidative damage to DNA, lipids, and proteins and modification of total antioxidant capacity (TAC) in saliva. Saliva was collected from 58 periodontitis patients and 234 healthy controls, all nonsmokers. Periodontal disease status was characterized using the Community Periodontal Index of Treatment Needs (CPITN). Assays for 8-OHdG (ELISA), 8-epi-PGF2α (ELISA), and total protein carbonyls (ELISA), and oxy-blotting (Western)/mass spectrometry were performed to quantify oxidative damage to nucleic acids, lipids, total and individual proteins, respectively, in whole nonstimulated saliva. Salivary TAC was measured by inhibition of ABTS oxidation by metmyoglobin. We observed (i) significantly higher levels of 8-OHdG, 8-epi-PGF2α, and carbonylated proteins in saliva of periodontal patients as compared with controls (P = 0.0003, < 0.0001 and < 0.0001); (ii) 8-OHdG, 8-epi-PGF2α, and carbonylated proteins were independently negatively associated with CPITN (P = 0.004, 0.02, and < 0.0001); (iii) a positive correlation between salivary TAC and periodontal disease status in the study group (P < 0.0001); and (iv) specific oxidation of transferrin, human IgG1 heavy chain fragment, and salivary amylase in periodontitis. Periodontal disease is associated with increased oxidative modification of salivary DNA, lipids, and proteins. Augmented salivary total antioxidant capacity may represent an adaptive response to oxidative stress. Salivary amylase, transferrin, and human IgG1 heavy chain fragments are particularly prone to enhanced oxidation in periodontitis.     

Melatonin stimulates antioxidant enzymes and reduces oxidative stress in experimental traumatic brain injury: the Nrf2–ARE signaling pathway as a potential mechanism

The goal of this study was to evaluate the potential involvement of melatonin in the activation of the nuclear factor erythroid 2-related factor 2 and antioxidant-responsive element (Nrf2–ARE) signaling pathway and the modulation of antioxidant enzyme activity in an experimental model of traumatic brain injury (TBI). In experiment 1, ICR mice were divided into four groups: sham group, TBI group, TBI + vehicle group, and TBI + melatonin group (n = 38 per group). Melatonin (10 mg/kg) was administered via an intraperitoneal (ip) injection at 0, 1, 2, 3, and 4 h post-TBI. In experiment 2, Nrf2 wild-type (Nrf2^+/+ group) and Nrf2-knockout (Nrf2^−/− group) mice received a TBI insult followed by melatonin administration (10 mg/kg, ip) at the corresponding time points (n = 35 per group). The administration of melatonin after TBI significantly ameliorated the effects of the brain injury, such as oxidative stress, brain edema, and cortical neuronal degeneration. Melatonin markedly promoted the translocation of Nrf2 protein from the cytoplasm to the nucleus; increased the expression of Nrf2–ARE pathway-related downstream factors, including heme oxygenase-1 and NAD(P)H:quinone oxidoreductase 1; and prevented the decline of antioxidant enzyme activities, including superoxide dismutase and glutathione peroxidase. Furthermore, knockout of Nrf2 partly reversed the neuroprotection of melatonin after TBI. In conclusion, melatonin administration may increase the activity of antioxidant enzymes and attenuate brain injury in a TBI model, potentially via mediation of the Nrf2–ARE pathway.     

Morphological characteristics of phytoliths from representative conifers in China

Coniferous phytoliths in sediments are an effective tool for detecting the historical appearance of conifers. However, at the timberline in mountainous areas, such coniferous phytoliths are easily confused with grass phytoliths. This study analyses modern phytoliths from 17 conifer plants. Six common types and six rare types were identified. The conifers studied produce abundant blocky polyhedral and cubic (in the average 30–40 μm size range), blocky scrobiculate (average 30–40 μm), tabular elongate unsculpted (length 50–100 μm, width 10–20 μm), tabular elongate cavate (length 50–150 μm, width ∼10 μm), tabular elongate dendritic (50–100 μm × 10–20 μm), and irregular oblong (20–40 μm) phytoliths. This paper aims to show morphological characteristics of coniferous phytoliths in China, and to show how the common coniferous phytoliths differ from similar grass phytolith types, such as blocky polyhedral coniferous phytoliths from silicified parallelepipedal bulliform cells produced by grass. Blocky polyhedral and cubic phytoliths are the commonest coniferous phytoliths found in the sediments, but need to be carefully distinguished from grass parallelepipedal bulliform cells. This study indicates that clearly protruding ridges and irregular inward edges are essential features of cubic and polyhedral morphotypes produced by conifers. Results of this paper might provide important material for the study of paleovegetation and paleoecology of mountainous areas, especially at the timberline.     

Study of folliculogenesis in vivo in guinea pig

Understanding normal folliculogenesis in guinea pigs is fundamental as a first step towards the development of a guinea pig follicle culture system. The aims of this study were (1) to characterise morphological changes during follicular development in vivo and (2) to describe the growth pattern of follicles. Cycling guinea pigs were infused with 5-bromo-2′-deoxyuridine for 1 or 2 weeks and sacrificed at time points ranging from 0 to 37 days after the infusion. The granulosa cell number in the largest cross-sections increased from 25.0 ± 6.1 (mean ± S.D.) in primary (type 2) to 192.0 ± 65.9 in preantral (type 5) and 256.3 ± 96.9 in antral (type 6) follicles. The oocyte diameter increased from 44.8 ± 6.2 μm (type 2) to 72.8 ± 9.1 μm (type 5) and 78.9 ± 9.3 μm (type 6) and the follicle diameter from 67.9 ± 10.1 μm (type 2) to 188.9 ± 29.7 μm (type 5) and 231.0 ± 56.1 μm (type 6). After a 1-week labelling period, about 71% of type 2 follicles had at least one labelled granulosa cell, as did 95% of type 3–4, and 100% of type 5 and 6. About 1 week was needed to achieve 95% mitotic activity in granulosa cells (GC) of type 5 and 6 follicles, while about 2 weeks was required to achieve 100% mitotic activity in GC of type 3–4 and more than 2 weeks for GC of type 2 follicles. These data provide some baselines for the examination of a guinea pig follicle culture system.     

Changes in the size distribution of goat steroidogenic luteal cells during pregnancy

Experiments were conducted to investigate the size distribution of goat steroidogenic luteal cells throughout pregnancy. Corpora lutea were collected from very early (<6 weeks), early (6–8 weeks), middle (9–14 weeks) or late (15–18 weeks) stages of pregnancy. Luteal tissue was dissociated into single-cell suspension by enzyme treatments. Cells were stained for 3β-hydroxysteroid dehydrogenase (3β-HSD) activity, a marker for steroidogenic cells. The steroidogenic cells covered a wide spectrum of size ranging from 5 to 45 μm in diameter. There was a significant increase in mean cell diameter (P>0.01) as pregnancy progressed. Mean diameter of 3β-HSD positive cells increased from 14.73±0.35 μm in the corpus luteum of very early pregnancy to 24.20±0.45 μm in the corpus luteum of late pregnancy. The ratio of large (>20 μm in diameter) to small (5–20 μm in diameter) luteal cells was 0.28:1.0 in very early pregnancy, with the 7.5–15 μm cell size class being dominant. However, the ratio of large-to-small luteal cells was increased to 1.77:1.0 μm as pregnancy advanced and 25–35 μm cell sizes became predominant. It is likely that small luteal cells could develop into large cells as pregnancy progresses. Development of pregnancy is also associated with an increase in size of steroidogenic luteal cells.     

Simultaneous determination of tryptophan and kynurenine in plasma samples of children patients with Kawasaki disease by high-performance liquid chromatography with programmed wavelength ultraviolet detection

A simple, fast, sensitive and specific high-performance liquid chromatography (HPLC) method is developed for simultaneous determination of kynurenine (Kyn) and tryptophan (Trp) with ultraviolet (UV) detection setting programmed wavelength. The separation was carried out on an Agilent Hypersil ODS column (125 mm × 4.0 mm, 5 μm) in less than 6 min and the eluate was monitored by the programmed wavelength detection setting at 360 nm from 0 min to 4 min for Kyn, and at 278 nm from 4 min to 6 min for Trp in a single run with UV detector. The linearities of the method were from 0.20 μmol/L to 21.2 μmol/L for Kyn and 2.25–678.0 μmol/L for Trp, and the detection limits were 0.028 μmol/L for Kyn and 0.053 μmol/L for Trp, respectively. Satisfactory precisions and recoveries were obtained by this method. The assay was employed to analyze plasma samples of children patients with Kawasaki disease (KD). The result showed great difference between Kawasaki disease and control group.     

Morphology and phylogeny of Henneguya jocu n. sp. (Myxosporea,Myxobolidae), infecting the gills of the marine fish Lutjanus jocu

Henneguya jocu n. sp. (Myxosporea, Myxobolidae) is described from the gill lamellae of the marine teleost fish Lutjanus jocu, with a focus on ultrastructural and molecular features. This myxosporean forms subspherical cysts up to ∼260 μm × 130 μm long, and develops asynchronously. Mature myxospores ellipsoidal with a bifurcated caudal process. Myxospore length 10.9 ± 0.4 μm (n = 50); width, 8.2 ± 0.3 μm (n = 50); and thickness, 2.9 ± 0.5 μm (n = 50). Two equal caudal processes, 34.1 ± 1.0 μm long (n = 50); and total myxospore length, 45.2 ± 1.0 μm (n = 50). Two symmetric valves surround two ellipsoidal polar capsules, 5.0 ± 0.3 × 1.4 ± 0.2 μm (n = 20), each containing an isofilar polar filament forming 4–5 coils along the inner wall of these structures, as well as a binucleated sporoplasm presenting a spherical vacuole and several globular sporoplasmosomes. Both the morphological data and molecular analysis of the SSU rDNA gene identify this parasite as a new species of the genus Henneguya. Maximum Likelihood and Maximum Parsimony analyses further indicate that the parasite clusters within others marine Myxobolidae species, forming a group alongside other Henneguya species described from marine hosts.     

Selection of developmentally competent buffalo oocytes by brilliant cresyl blue staining before IVM

The brilliant cresyl blue (BCB) test determines the activity of glucose-6-phosphate dehydrogenase (G6PDH); the activity of this enzyme is greatest in growing oocytes, but it declines as oocytes mature. The objective was to develop and evaluate this test for assessing development of buffalo oocytes (to select developmentally competent oocytes for increased in vitro embryo production). Oocytes were exposed to BCB stain diluted in mDPBS (DPBS with 0.4% BSA) for 90 min at 38.5 °C in a humidified air atmosphere; those with or without blue coloration of the cytoplasm were designated as BCB+ and BCB−, respectively. In Experiment 1, oocytes were exposed to 13, 26, or 39 μM BCB. There were fewer BCB+ oocytes after exposure to 13 μM BCB (10%) than after exposure to 26 or 39 μM BCB (57.2 and 61.8%; P < 0.05), but there was no significant difference among treatments for blastocyst production rate. In Experiment 2, the diameter of BCB+ oocytes (144.4 ± 4.2 μm; mean ± S.E.M.) was higher (P < 0.05) than that of BCB− oocytes (136.8 ± 4.6 μm). In Experiment 3, oocytes were allocated into three groups: control (immediately cultured); holding-control (kept in mDPBS for 90 min before cultured); and treatment-incubation (incubated with 26 μM BCB). After IVM, oocytes were fertilized in vitro and cultured on an oviductal monolayer. The nuclear maturation rate was higher (P < 0.05) in BCB+ (86.2%), control (83.4%) and holding-control (82.6%) oocytes than BCB− (59.2%) oocytes. The BCB+ oocytes yielded more blastocysts than control or holding-control oocytes (33.4, 20.2, and 21.0%, P < 0.05); blastocyst development was lowest in BCB− oocytes (5.2%). In conclusion, staining of buffalo oocytes with BCB before IVM may be used to select developmentally competent oocytes for increased in vitro embryo production.     

Time-course correlation of early toxic events in three models of striatal damage: Modulation by proteases inhibition

Metabolic alterations in the nervous system can be produced at early stages of toxicity and are linked with oxidative stress, energy depletion and death signaling. Proteases activation is responsible for triggering deadly cascades during cell damage in toxic models. In this study we evaluated the early time-course of toxic events (oxidative damage to lipids, mitochondrial dysfunction and LDH leakage, all at 1, 3 and 6 h) in rat striatal slices exposed to quinolinic acid (QUIN, 100 μM) as an excitotoxic/pro-oxidant model, 3-nitropropionic acid (3-NP, 1 mM) as an inhibitor of mitochondrial succinate dehydrogenase, and a combined model produced by the co-administration of these two toxins at subtoxic concentrations (21 and 166 μM for QUIN and 3-NP, respectively). In order to further characterize a possible causality of caspases or calpains on the toxic mechanisms produced in these models, the broad calpain inhibitor IC1 (50 μM), and the pan-caspase inhibitor Z-VAD (100 μM) were tested. Lipid peroxidation (LP) was increased at all times and in all models evaluated. Both IC1 and Z-VAD exerted significant protection against LP in all models and at all times evaluated. Mitochondrial dysfunction (MD) was consistently affected by all toxic models at 3 and 6 h, but was mostly affected by 3-NP and QUIN at 1 h. IC1 differentially protected the slices against 3-NP and QUIN at 1 h and against QUIN at 3 h, while Z-VAD exhibited positive actions against QUIN and 3-NP at all times tested, and against their combination at 3 and 6 h. LDH leakage was enhanced at 1 and 3 h in all toxic models, but this effect was evident only for 3-NP + QUIN and 3-NP at 6 h. IC1 protected against LDH leakage at 1 h in 3-NP + QUIN and 3-NP models, at 3 h in all toxic models, and at 6 h in 3-NP + QUIN and 3-NP models. In turn, Z-VAD protected at 1 and 6 h in all models tested, and at 3 h in the combined and QUIN models. Our results suggest differential chronologic and mechanistic patterns, depending on the toxic insult. Although LP, MD and membrane cell rupture are shared by the three models, the occurrence of each event seems to obey to a selective recruitment of damaging signals, including a differential activation of proteases in time. Proteases activation is likely to be an up-stream event influencing oxidative stress and mitochondrial dysfunction in these toxic models.     

Sources of variation contributing to production and quality attributes of Kyrgyz cashmere in Osh and Naryn provinces: Implications for industry development

We aimed to quantify the sources of variation contributing to the production and quality of cashmere produced in five districts in Osh and Naryn provinces of Kyrgyzstan. In early spring 2008 mid-side cashmere samples were taken from 719 cashmere adult females, and 41 cashmere adult males and castrates. Samples came from 53 villages and a total of 156 farmers’ flocks. For 91 goats from 33 farmers in 13 villages of two districts that had been sampled earlier, cashmere was combed from the goat at the time of a second visit (end of April 2008) when the cashmere would normally be harvested. Following standard cashmere objective measurement, data were examined using general linear modelling to quantify the effects of potential determinants. The mean fibre diameter (MFD) of cashmere differed between provinces (Osh 15.7 μm, Naryn 16.7 μm; P = 4.4 × 10⁻²⁰). About 42% of the cashmere was <16 μm, 48% was 16.0–18.0 μm and 9.5% was >18.0 μm. Most of the cashmere samples were coloured (81%), with 63% black and 19% white. The percentage of cashmere samples that were white declined as MFD increased (26% < 14 μm to 11% of >18 μm). The primary determinants of cashmere MFD of individual goats were age of goat (range 1.46 μm, P = 1.8 × 10⁻¹²) and farm (range 6.5 μm, P = 1.7 × 10⁻¹⁴). The lesser effects detected for sex (range 0.9 μm, P = 0.026) and colour of cashmere (range 1.8 μm, P = 0.023) were based on small sample sizes and are unreliable. Age of goat had important affects on fibre diameter variation (up to 1.7% in coefficient of variation, P = 5.8 × 10⁻⁶) and fibre curvature (2.5–5°/mm, P = 2.1 × 10⁻⁴). By far the greatest effect on fibre curvature was cashmere MFD (P = 3.0 × 10⁻¹⁰⁴) with a smaller effect of sex (about 5°/mm, P = 3.0 × 10⁻⁶). Village effects were detected on fibre diameter variability (range 4.5% in coefficient of variation, P = 0.027) and fibre curvature (range 15°/mm, P = 1.6 × 10⁻⁷). There was a strong negative association between increasing MFD and declining fibre curvature (−5.11 ± 0.181°/mm per 1 μm; P = 7.1 × 10⁻¹²¹; r² = 0.51). Average combed cashmere weight was 164 g, the clean cashmere content was 0.661 and median clean cashmere production was 110 g per goat (range 60–351 g). Combed cashmere production increased with altitude of the village, probably related to different moulting times as spring temperatures warmed up later in higher altitude villages up to 3200 masl. Measurements of combed cashmere MFD were coarser than the mid-side samples taken earlier in the year. There are farmers and cashmere goats in the sampled districts of Kyrgyzstan which produce the finest qualities of commercial cashmere as the vast majority of cashmere is fine, has low variation in fibre diameter and has fibre crimping (curvature) typical of Chinese and Mongolian cashmere. There is substantial scope to increase the production and commercial value of cashmere produced by Kyrgyz goats. In particular, some villages and farmers need to change their buck selection practices if they wish to produce acceptable cashmere. Farmers should separate their finer and white cashmere prior to sale.     

Association between periodontitis and common variants in the promoter of the interleukin-6 gene

We recently reported an association between interleukin-6 (IL6) polymorphisms (SNPs) and haplotypes and aggressive periodontitis (AgP). The aim of this study was to investigate this association in a larger cohort of subjects, affected by either aggressive or chronic periodontitis. Five IL6 SNPs were analyzed in 765 subjects (167 generalized aggressive periodontitis, 57 localized aggressive, 310 chronic periodontitis and 231 periodontally healthy). Among Caucasians (n = 454) there were moderate associations for ?1363T allele (p = 0.011) and for ?174GG and ?1363GG genotypes with diagnosis of periodontitis (respectively, p = 0.044, OR = 1.6, 95% CI = 1.0–2.4, and p = 0.017, OR = 1.8, 95% CI = 1.1–2.8, adjusted for age, gender and smoking). Haplotypes containing the ?174G>C, ?1363G>T and ?1480C>G polymorphisms were associated with diagnosis of periodontitis (p = 0.02). Subgroup analysis by disease phenotype showed associations for the localized AgP (LAgP) group and ?1480C>G and ?6106A>T SNPs (p = 0.007 and 0.010, respectively). Among Caucasians the genotypes IL6 ?1480 CC and ?6106 TT increased the adjusted OR for LAgP (OR = 3.09 and 2.27, respectively). This study supports the hypothesis that IL6 polymorphisms and haplotypes are moderately associated with periodontitis, possibly acting through influencing tissue levels of IL6. This association is stronger for LAgP than for other periodontal disease phenotypes.     

Oral administration of melatonin modulates the expression of tumor necrosis factor-α (TNF-α) gene in irradiated rat cervical spinal cord

AimWe aimed to determine the changes in TNF-α expression and Malondialdehyde (MDA) level in a short time after irradiation. Furthermore, we evaluated the effect of melatonin on the modulation of TNF-α gene expression.BackgroundThe radio-sensitivity of the cervical spinal cord limits the dose of radiation which can be delivered to tumors in the neck region. There is increasing evidence that TNF-α has a role in the development of the acute phase of spinal cord injury.Materials/MethodsFour groups of rats were investigated. Group 1 (vehicle treatment) served as the control. Group 2 (radiation) was treated with the vehicle, and 30 min later, the rats were exposed to radiation. Group 3 (radiation + melatonin) was given an oral administration of melatonin (100 mg/kg body weight) and 30 min later exposed to radiation in the same manner as in group 2. Group 4 (melatonin-only) was also given an oral administration of melatonin (100 mg/kg body weight). 5 mg/kg of melatonin was administered daily to rats in groups 3 and 4, and the vehicle was administered daily to rats in groups 1 and 2.ResultsThree weeks after irradiation, TNF-α gene up-regulated almost 5 fold in the irradiated group compared to the normal group. TNF-α gene expression in the melatonin pretreatment group, compared to the radiation group, was significantly down-regulated 3 weeks after irradiation (p < 0.05). MDA levels increased after irradiation and then significantly decreased under melatonin treatment.ConclusionWe suggest that inhibition of TNF-α expression by oral administration of melatonin may be a therapeutic option for preventing radiation-induced spinal cord injury.     

Evidence that metyrapone in the presence of inflammation modulates cytokine mRNA expression

ObjectiveMetyrapone (MT) has been used clinically to decrease glucocorticoid levels in human and animal studies. However, the potential effects of MT in the presence of inflammation are poorly understood. Thus, the aim of this study was to evaluate the effects of the administration of MT on the mRNA levels of pro-inflammatory cytokines in the presence of inflammation induced by the well-established model of ligature-induced periodontitis in rats.Material and methodsSixty animals were randomly assigned into three experimental groups of 20 rats each: G1-control; G2-periodontal disease (PD) induced by cotton ligature; G3-PD associated with 3 daily doses of MT (50 mg/kg/3 × 3 h). After 30 days, all animals were killed by decapitation. Blood samples were taken and the concentrations of corticosterone and catecholamines measured. Marginal tissues around ligated and non-ligated teeth were harvested and gene expression was assessed by quantitative polymerase chain reaction technique (qPCR). Moreover, the area of interradicular bone loss (ABL) was histometrically determined.ResultsData analysis showed that: (i) ligature placement resulted in a significant ABL, as compared to non-ligated sites of G1 group; (ii) mRNA levels of all the pro-inflammatory factors assessed (INF-γ, TNF-α, IL-1β and IL-6) were increased in the PD group (G2) (p < 0.05) when compared to G1; (iii) there were no significant differences in corticosterone and catecholamine plasmatic levels between the three groups; (iv) MT administration, in the presence of inflammation, induces an increased ABL and significantly increased mRNA levels of all pro-inflammatory cytokines analyzed (p < 0.05).ConclusionWithin the limits of this study, it can be concluded that MT in the presence of inflammation may modulate expression of pro-inflammatory cytokines, regardless of its effect on plasma corticosterone levels.     

Selenium status in elderly: Relation to cognitive decline

Studies show that decreased antioxidant system is related to cognitive decline. Thus we aimed to measure selenium (Se) status in Alzheimer's disease (AD) and mild cognitive impairment (MCI) elderly and compared them with a control group (CG). 27 AD, 17 MCI and 28 control elderly were evaluated. Se concentration was determined in plasma and erythrocyte by using hydride generation atomic absorption spectroscopy. Erythrocyte Se concentration in AD group was lower than CG (43.73 ± 23.02 μg/L and 79.15 ± 46.37 μg/L; p = 0.001), but not statistically different from MCI group (63.97 ± 18.26 μg/L; p = 0.156). AD group exhibited the lowest plasma Se level (34.49 ± 19.94 μg/L) when compared to MCI (61.36 ± 16.08 μg/L; p = 0.000) and to CG (50.99 ± 21.06 μg/L; p = 0.010). It is observed that erythrocyte Se decreases as cognition function does. Since erythrocyte reflects longer-term nutritional status, the data point to the importance of the relation between Se exposure and cognitive function. Our findings suggest that the deficiency of Se may contribute to cognitive decline among aging people.     

Exogenous and endogenous stages of Eimeria perforans naturally infected domestic rabbit (Oryctolagus cuniculus) in Saudi Arabia: Light microscopic study

Exogenous and endogenous stages of Eimeria perforans naturally infected rabbits in Saudi Arabia were described. The prevalence of infection was 75%. Oocysts were ovoid to elliptical and measured 16 × 10 μm. The four dizoic sporocysts were ovoid and measured 7 × 5 μm. Endogenous stages were restricted to the duodenum. Meronts, microgamonts, macrogamonts and young oocysts were recorded and described.     

Body-size spectra of biofilm-dwelling protozoa and their seasonal shift in coastal ecosystems

Community-based assessment of protozoa is usually performed at a taxon-dependent resolution. As an inherent ‘taxon-free’ trait, however, body-size spectrum has proved to be a highly informative indicator to summarize the functional structure of a community in both community research and monitoring programs in aquatic ecosystems. To demonstrate the relationships between the taxon-free resolution of protozoan communities and water conditions, the body-size spectra of biofilm-dwelling protozoa and their seasonal shift and environmental drivers were explored based on an annual dataset collected monthly from coastal waters of the Yellow Sea, northern China. Body sizes were calculated in equivalent spherical diameter (ESD). Among a total of 8 body-size ranks, S2 (19–27 μm), S3 (28–36 μm), S4 (37–50 μm) and S5 (53–71 μm) were the top four levels in frequency of occurrence, while rank S1 (13–17 μm), S2 and S4 were the dominant levels in abundance. These dominants showed a clear seasonal succession: S2/S4 (spring) → S2/S4 (summer) → S4 (autumn) → S2 (winter) in frequency of occurrence; S1 (spring) → S4 (summer) → S2 (autumn) → S1 (winter) in abundance. Bootstrapped average analysis showed a clear seasonal shift in body-size spectra of the protozoa during a 1-year cycle, and the best-matching analysis demonstrated that the temporal variations in frequency of occurrence and abundance were significantly correlated with water temperature, pH, dissolved oxygen (DO), alone or in combination with chemical oxygen demand (COD) and nutrients. Thus, the body-size spectra of biofilm-dwelling protozoa were seasonally shaped and might be used as a time and cost efficient bioindicator of water quality in marine ecosystems.     

Biomorphometric characteristics of different types of sensilla detected on the antenna of Helicoverpa armigera by scanning electron microscopy

A morphometric study on H. armigera antenna showed four styles of sensilla, i.e., styloconica, chaetica, coeloconica, and trichodea, and their numbers were estimated. Sensilla trichodea detect inter and intraspecific communication signals and was the most numerous. They were divided into three types: type I, the longest, with a length of 34.04 ± 3.16 μm and about 2.16 to 2.42 μm in diameter at its base; 2) type II, intermediate, with a length of 22.58 ± 0.77 μm and basal diameter of 1.8–2.52 μm; 3) type III, the shortest sensilla trichodea, with a length of 7.62 ± 0.4 μm and a range in diameter similar to that of type II. The length of the female sensilla trichodea was longer than that of the male. The total number of sensilla trichodea was estimated to be 7520 on the antenna of the female, and 6831 on the male antenna. The lengths of the sensilla trichodea type I and type III were significantly different on male (t = 4.6881, P = 0.0034) and female antenna (t = 18.9852, P = 0.0001). An estimation of the predicted surface area of the most numerous type I on sampled segments between the 12th and 20th segments from a female of H. armigera showed a surface area of 5 × 10³ μm² and a sensillar density of 38 sensilla/10³ μm². The fraction of sensilla-occupied surface area was 0.4 μm².     

Altered sarcoplasmic reticulum calcium transport in the presence of the heavy metal chelator TPEN

TPEN (N,N,N′,N′-tetrakis(2-pyridylmethyl)-ethylenediamine) is a membrane-permeable heavy-metal ion chelator with a dissociation constant for Ca²⁺ comparable to the Ca²⁺ concentration ([Ca²⁺]) within the intracellular Ca²⁺ stores. It has been used as modulator of intracellular heavy metals and of free intraluminal [Ca²⁺], without influencing the cytosolic [Ca²⁺] that falls in the nanomolar range. In our previous studies, we gave evidence that TPEN modifies the Ca²⁺ homeostasis of striated muscle independent of this buffering ability. Here we describe the direct interaction of TPEN with the ryanodine receptor (RyR) Ca²⁺ release channel and the sarcoplasmic reticulum (SR) Ca²⁺ pump (SERCA). In lipid bilayers, at negative potentials and low [Ca²⁺], TPEN increased the open probability of RyR, while at positive potentials it inhibited channel activity. On permeabilized skeletal muscle fibers of the frog, but not of the rat, 50 μM TPEN increased the number of spontaneous Ca²⁺ sparks and induced propagating events with a velocity of 273 ± 7 μm/s. Determining the hydrolytic activity of the SR revealed that TPEN inhibits the SERCA pump, with an IC₅₀ = 692 ± 62 μM and a Hill coefficient of 0.88 ± 0.10. These findings provide experimental evidence that TPEN directly modifies both the release of Ca²⁺ from and its reuptake into the SR.