Effect of a calcium silicate cement and experimental glass ionomer cements containing calcium orthophosphate particles on demineralized dentin.

OBJECTIVE: The study aims to evaluate the effect of a glass ionomer cement (GIC; Fuji 9 Gold Label, GC) with added calcium orthophosphate particles and a calcium silicate cement (CSC; Biodentine, Septodont) regarding ion release, degradation in water, mineral content, and mechanical properties of demineralized dentin samples. METHODS: GIC, GIC + 5% DCPD (dicalcium phosphate dihydrate), GIC + 15% DCPD, GIC + 5% ß-TCP (tricalcium phosphate), GIC + 15% ß-TCP (by mass), and CSC were evaluated for Ca2+/Sr2+/F- release in water for 56 days. Cement mass loss was evaluated after 7-day immersion in water. Partially demineralized dentin disks were kept in contact with materials while immersed in simulated body fluid (SBF) at 37 °C for 56 days. The "mineral-to-matrix ratio" (MMR) was determined by ATR-FTIR spectroscopy. Dentin hardness and elastic modulus were obtained by nanoindentation. Samples were observed under scanning and transmission electron microscopy. Data were analyzed by ANOVA/Tukey test (α = 0.05). RESULTS: Ca2+ release from CSC and GIC (µg/cm2) were 4737.0 ± 735.9 and 13.6 ± 1.6, respectively. In relation to the unmodified GIC, the addition of DCPD or ß-TCP increased ion release (p < 0.001). Only the dentin disks in contact with CSC presented higher MMR (p < 0.05) and mechanical properties than those restored with a resin composite used as control (p < 0.05). Mass loss was similar for GIC and CSC; however, the addition of DCPD or ß-TCP increased GIC degradation (p < 0.05). CONCLUSION: Despite the increase in ion release, the additional Ca2+ sources did not impart remineralizing capability to GIC. Both unmodified GIC and CSC showed similar degradation in water. CLINICAL RELEVANCE: CSC was able to promote dentin remineralization.

The Sleep Parameters of Paralympic Athletes: Characteristics and Assessment Instruments.

CONTEXT: Sleep serves many important functions for athletes, particularly in the processes of learning, memory, recovery, and cognition. OBJECTIVES: Define the sleep parameters of Paralympic athletes and identify the instruments used to assess and monitor sleep Paralympic athletes. EVIDENCE ACQUISITION: This systematic review was carried out based on the PRISMA guidelines. The survey was conducted in April 2020, the searches were carried out again in September 2021 to check whether there were new scientific publications in the area of sleep and Paralympic sport, searches were performed in the following databases: PubMed, Web of Science, Scopus, SPORTDiscus, Virtual Health Library (BIREME), and SciELO. This systematic review has included studies that investigated at least one of the following sleep parameters: total sleep time, sleep latency, sleep efficiency, number of awakenings, quality of sleep, daytime sleepiness, and chronotype; the participants were comprised of athletes with disabilities. Studies published at any time in English, Portuguese, and Spanish, were included. EVIDENCE SYNTHESIS: Data extraction and study selection were performed by 2 researchers independently, and a third author was consulted as necessary. The search returned a total of 407 studies. Following the screening based on exclusion and inclusion criteria, a total of 13 studies were considered. Paralympic athletes have a low amount (7.06 h) of sleep with poor quality and sleep latency (28.05 min), and 57.2% have daytime sleepiness, with the majority belonging to the indifferent chronotype (53, 5%). Moreover, 11 studies assess sleep using subjective instruments (questionnaires), and 2 studies used an objective instrument (actigraphy). CONCLUSIONS: Sleep disorders are common among Paralympic athletes, poor sleep quality and quantity, and high rates of daytime sleepiness. Subjective methods are most commonly used to assess sleep.

The mGluR5 positive allosteric modulator VU0409551 improves synaptic plasticity and memory of a mouse model of Huntington's disease.

Huntington's Disease (HD) is an autosomal-dominant neurodegenerative disorder, characterized by involuntary body movements, cognitive impairment, and psychiatric disorder. The metabotropic glutamate receptor 5 (mGluR5) plays an important role in HD and we have recently demonstrated that mGluR5-positive allosteric modulators (PAMs) can ameliorate pathology and the phenotypic signs of a mouse model of HD. In this study, we investigated the molecular mechanisms involved in mGluR5 PAMs effect on memory. Our results demonstrate that subchronic treatment with the mGluR5 PAM VU0409551 was effective in reversing the memory deficits exhibited by BACHD mice, a mouse model for HD. Moreover, VU0409551 treatment stabilized mGluR5 at the cellular plasma membrane of BACHD mice, increasing the expression of several genes important for synaptic plasticity, including c-Fos, brain-derived neurotrophic factor, Arc/Arg3.1, syntaxin 1A, and post-synaptic density-95. In addition, VU0409551 treatment also increased dendritic spine density and maturation and augmented the number of pre-synaptic sites. In conclusion, our results demonstrate that VU0409551 triggered the activation of cell signaling pathways important for synaptic plasticity, enhancing the level of dendritic spine maturation and rescuing BACHD memory impairment. OPEN PRACTICES: Open Science: This manuscript was awarded with the Open Materials Badge. For more information see: https://cos.io/our-services/open-science-badges/.

Thiamine Deficiency Increases Ca2+ Current and CaV1.2 L-type Ca2+ Channel Levels in Cerebellum Granular Neurons.

Thiamine (vitamin B1) is co-factor for three pivotal enzymes for glycolytic metabolism: pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase. Thiamine deficiency leads to neurodegeneration of several brain regions, especially the cerebellum. In addition, several neurodegenerative diseases are associated with impairments of glycolytic metabolism, including Alzheimer's disease. Therefore, understanding the link between dysfunction of the glycolytic pathway and neuronal death will be an important step to comprehend the mechanism and progression of neuronal degeneration as well as the development of new treatment for neurodegenerative states. Here, using an in vitro model to study the effects of thiamine deficiency on cerebellum granule neurons, we show an increase in Ca2+ current density and CaV1.2 expression. These results indicate a link between alterations in glycolytic metabolism and changes to Ca2+ dynamics, two factors that have been implicated in neurodegeneration.

Reproductive and genital health and risk of cervical human papillomavirus infection: results from the Ludwig-McGill cohort study.

BACKGROUND: There are inconsistencies in the literature on reproductive and genital health determinants of human papillomavirus (HPV) infection, the primary cause of cervical cancer. We examined these factors in the Ludwig-McGill Cohort Study, a longitudinal, repeated-measurements investigation on the natural history of HPV infection. METHODS: We analyzed a cohort subset of 1867 women with one complete year of follow-up. We calculated odds ratios (OR) and 95% confidence intervals (CI) for reproductive and genital health characteristics from questionnaire and laboratory data in relation to 1-year period prevalence of HPV infection. Two outcomes were measured; the first based on phylogenetic grouping of HPV types based on tissue tropism and oncogenicity (Alphapapillomavirus Subgenus 1: species 1, 8, 10 and 13; Subgenus 2: species 5, 6, 7, 9, 11; Subgenus 3: species 3, 4 and 14) and the second based on transient or persistent HPV infections. RESULTS: Lifetime (Subgenus 3 OR = 2.00, CI: 1.23-3.24) and current (Subgenus 3 OR =2.00, CI: 1.15-3.47) condom use and use of contraceptive injections (Subgenus 1 OR = 1.96, CI: 1.22-3.16, Subgenus 2 OR = 1.34, CI: 1.00-1.79) were associated with increased risk of HPV infection. Intrauterine device use was protective (Subgenus 1 OR = 0.48, CI: 0.30-0.75, Subgenus 2 OR = 0.78, CI: 0.62-0.98). These factors were not associated with persistence of HPV infection. Tampon use, previous gynecologic infections and cervical inflammation were associated with an overall increased risk of HPV infection. CONCLUSIONS: Cervical HPV infection was associated with reproductive and genital health factors. Further studies are necessary to confirm the low to moderate associations observed.

Expression of Genes Involved in Porphyrin Biosynthesis Pathway in the Human Renal Cell Carcinoma.

Renal cell carcinoma (RCC) remains one of the greatest challenges of urological oncology and is the third leading cause of death in genitourinary cancers. Surgery may be curative when patients present with localized disease. Our previous results demonstrated the autofluorescence of blood PpIX in primary RCC mouse model and an increase in fluorescence intensity as a function of growth of the subcutaneous tumor mass. In another work, a nice correlation between the growth of the tumor mass and tissue fluorescence intensity was found. The aim of this study was to evaluate the expression profile of porphyrin biosynthesis pathway-related genes of human kidney cells. We used two kidney cell lines, one normal (HK2) and another malignant (Caki-1). Endogenous and 5-aminolevolinic acid (ALA) induced protoporphyrin IX (PpIX) HK2 and Caki-1 cells were analyzed by fluorescence spectroscopy. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to measure mRNA of those genes. Emission spectra were obtained by exciting the samples at 405 nm. For ALA untreated cells the maximum fluorescence intensity was detected at 635 nm. The mean peak area of emission spectra in both cells types increased linearly in function of cell number. Besides, basal levels of PpIX autofluorescence of each cell concentration of HK2 samples were significantly lower than those of Caki-1 samples. For ALA-treated cells the mean PpIX spectra shows PpIX emission peak at 635 nm with a shoulder at 700 nm. Analysis of PpIX fluorescence intensity ratio between tumor cells and HK2 cells showed that fluorescence intensity was, on average, 26 times greater in tumor cells than in healthy cells. qRT-PCR revealed that in Caki-1 ALA-treated cells, PEPT gene was significantly up-regulated and FECH and HO-1 genes were significantly down regulated in comparison with HK2 ALA-treated cells. In conclusion, our results demonstrate the preferential accumulation of ALA-induced PpIX in human RCC and also indicate that PEPT1, FECH and HO-1 genes are major contributors to this accumulation.

Physicochemical characterization of experimental resin-based materials containing calcium orthophosphates or calcium silicate.

OBJECTIVE: To evaluate experimental dimethacrylate-based materials containing calcium orthophosphates or calcium silicate particles in terms of their optical, mechanical and Ca2+ release behaviour. METHODS: Dicalcium phosphate dihydrate (DCPD), hydroxyapatite (HAp), beta-tricalcium phosphate (ß-TCP) or calcium silicate (CaSi) particles were added to a photocurable BisGMA/TEGDMA resin (1:1 in mols) at a 30 vol% fraction. Materials containing silanized or non-silanized barium glass particles were used as controls. Degree of conversion (DC) at the top and base of 2-mm thick specimens was determined by ATR-FTIR spectroscopy (n = 5). Translucency parameter (TP) and transmittance (%T) were determined using a spectrophotometer (n = 3). Biaxial flexural strength (BFS) and flexural modulus (FM) were determined by biaxial flexural testing after 24 h storage in water (n = 10). Ca2+ release in water was determined during 28 days by inductively coupled plasma optical emission spectrometry (n = 3). Statistical analysis was performed using ANOVA/Tukey test (DC: two-way; TP, %T; BFS and FM: one-way; Ca2+ release: repeated measures two-way, α = 5 %). RESULTS: CaSi and ß-TCP particles drastically reduced DC at 2 mm, TP and %T (p < 0.001). Compared to both controls, all Ca2+-releasing materials presented lower BFS (p < 0.001) and only the material with DCPD showed significantly lower FM (p < 0.05). The material containing CaSi presented the highest Ca2+ release, while among materials formulated with calcium orthophosphates the use of DCPD resulted in the highest release (p < 0.001). SIGNIFICANCE: CaSi particles allowed the highest Ca2+ release. Notwithstanding, the use of DCPD resulted in a material with the best compromise between optical behaviour, DC, strength and Ca2+ release.

Study of protoporphyrin IX elimination by body excreta: a new noninvasive cancer diagnostic method?

This paper describes the elimination of porphyrins by feces. It was demonstrated that porphyrin accumulates substantially more in tumors than in normal tissues, and consequently more PPIX reaches the blood of patients and animals with tumors, and then, it needs to be eliminated. The fluorescence of feces revealed that there are large amounts of PPIX in the excreta of animals with cancer comparing with healthy animals. The autofluorescence of feces porphyrin extracted with acetone was analyzed using fluorescence spectroscopy of animals inoculated with DU145 cells into the prostate and healthy animals to monitor the PPIX concentration. Emission spectra were obtained by exciting the samples at 405 nm. Significant differences were observed in autofluorescence intensities measured in the 575-725 nm spectral regions for the studied groups. The results showed a noninvasive, simple, rapid and sensitive method to detect cancer by feces analysis.

Maternal dietary zinc status alters offspring female mammary gland development and response to acute 7,12-dimethylbenzanthracene insult.

We evaluated the effects of prenatal and postnatal dietary zinc (Zn) deficiency or supplementation on mammary gland morphology and on acute response to 7,12-dimethylbenzanthracene (DMBA) in pubertal female rats. On gestational day 10 (GD 10), rat dams were allocated randomly into three experimental groups of 10: a Zn-adequate diet group (ZnA) fed 35 mg Zn/kg chow, a Zn-deficient diet group (ZnD) fed 3 mg ZN/kg chow and a Zn-supplemented diet group (ZnS) fed 180 mg Zn/kg chow. After weaning, female offspring were fed the same diet as their dams until postnatal day 53 (PND 53). All animals received a single 50 mg/kg dose of DMBA on PND 51 and were euthanized on PND 53. Female ZnD offspring exhibited significantly less weight gain compared to the ZnA group and reduced mammary gland development compared to the ZnD and ZnA groups. By PND 53, the Ki-67 labeling index in mammary gland epithelial cells was significantly greater for the ZnS group than for the ZnA and ZnD groups. Apoptosis and ER-α indices did not differ among groups. The ZnD group exhibited significantly increased lipid hydroperoxide (LOOH) levels and decreased catalase and glutathione peroxidase (GSH-Px) activity compared to the ZnA and ZnS groups. The ZnS group exhibited significantly reduced superoxide dismutase (SOD) activity compared to the ZnA and ZnS groups. We observed atypical ductal hyperplasia in the mammary gland of female ZnS group offspring compared to the ZnA and ZnD groups and decreased expression of the Api5 and Ercc1 genes related to apoptosis inhibition and DNA damage repair, respectively. Both the Zn-deficient and Zn-supplemented diet exerted adverse effects on offspring mammary gland morphology and acute response to DMBA.

In vivo Activity of Silver Nanoparticles Against Pseudomonas aeruginosa Infection in Galleria mellonella.

Pseudomonas aeruginosa is an opportunistic pathogen associated with life-threatening nosocomial and community-acquired infections. Antibiotic resistance is an immediate threat to public health and demands an urgent action to discovering new antimicrobial agents. One of the best alternatives for pre-clinical tests with animal models is the greater wax moth Galleria mellonella. Here, we evaluated the antipseudomonal activity of silver nanoparticles (AgNPs) against P. aeruginosa strain UCBPP-PA14 using G. mellonella larvae. The AgNPs were synthesized through a non-toxic biogenic process involving microorganism fermentation. The effect of AgNPs was assessed through characterization and quantification of the hemocytic response, nodulation and phenoloxidase cascade. On average, 80% of the larvae infected with P. aeruginosa and prophylactically treated with nanoparticles survived. Both the specific and total larvae hemocyte counts were restored in the treated group. In addition, the nodulation process and the phenoloxidase cascade were less exacerbated when the larvae were exposed to the silver nanoparticles. AgNPs protect the larvae from P. aeruginosa infection by directly killing the bacteria and indirectly by preventing an exacerbated immunological response against the pathogen. Our results suggest that the prophylactic use of AgNPs has a strong protective activity against P. aeruginosa infection.

Early-in-life dietary zinc deficiency and supplementation and mammary tumor development in adulthood female rats.

Zinc deficiency during pregnancy and postnatal life can adversely increase risk of developing human diseases at adulthood. The present study was designed to evaluate whether dietary zinc deficiency or supplementation during the pregnancy, lactation and juvenile stages interferes in the development of mammary tumors induced by 7,12-dimethylbenzanthracene (DMBA) in female Sprague-Dawley (SD) rats. Pregnant female SD rats were allocated into three groups: zinc-adequate diet (ZnA - 35-mg/kg chow), zinc-deficient diet (ZnD - 3-mg/kg chow) or zinc-supplemented diet (ZnS - 180-mg/kg chow) during gestational day 10 (GD 10) until the litters' weaning. Female offspring received the same diets as their dams until postnatal day (PND) 51. At PND 51, the animals received a single dose of DMBA (50 mg/kg, ig) and zinc-adequate diets. At PND 180, female were euthanized, and tumor samples were processed for histological evaluation and gene expression microarray analysis. The ZnD induced a significant reduction in female offspring body weight evolution and in mammary gland development. At late in life, the ZnD or ZnS did not alter the latency, incidence, multiplicity, volume or histological types of mammary tumors in relation to the ZnA group. However, the total tumor number in ZnS group was higher than in ZnA group, accompanied by distinct expression of 4 genes up- and 15 genes down-regulated. The present findings indicate that early-in-life dietary zinc supplementation, differently to zinc deficiency, has a potential to modify the susceptibility to the development of mammary tumors induced by DMBA.

N-type Ca2+ channels are affected by full-length mutant huntingtin expression in a mouse model of Huntington's disease.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by a polyglutamine expansion in the amino-terminal region of the huntingtin (htt) protein. In addition to facilitating neurodegeneration, mutant htt is implicated in HD-related alterations of neurotransmission. Previous data showed that htt can modulate N-type voltage-gated Ca2+ channels (Cav2.2), which are essential for presynaptic neurotransmitter release. Thus, to elucidate the mechanism underlying mutant htt-mediated alterations in neurotransmission, we investigated how Cav2.2 is affected by full-length mutant htt expression in a mouse model of HD (BACHD). Our data indicate that young BACHD mice exhibit increased striatal glutamate release, which is reduced to wild type levels following Cav2.2 block. Cav2.2 Ca2+ current-density and plasma membrane expression are increased in BACHD mice, which could account for increased glutamate release. Moreover, mutant htt affects the interaction between Cav2.2 and 2 major channel regulators, namely syntaxin 1A and Gßγ protein. Notably, 12-month old BACHD mice exhibit decreased Cav2.2 cell surface expression and glutamate release, suggesting that Cav2.2 alterations vary according to disease stage.

Maternal Resveratrol Treatment Reduces the Risk of Mammary Carcinogenesis in Female Offspring Prenatally Exposure to 2,3,7,8-Tetrachlorodibenzo-p-Dioxin.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) presents adverse effects on breast development/carcinogenesis. This study aimed to identify the ability of resveratrol (Res) to modify the adverse effects of TCDD in a female offspring. Pregnant female Wistar rats were allocated into four groups: TCDD, TCDD + Res, Res, and control. TCDD (1 µg/kg) was orally administered as a single dose on gestational day (GD) 15, and Res was orally administered during GD10-21 and lactation at a dose of 20 mg/kg/day. Female offsprings were euthanized on a specific postnatal day (PND) for hormonal analysis (PND 22, 48-51), vaginal opening (PND 30-48), and mammary gland morphology (PND 22). Other females received two doses of N-nitroso-N-methylurea (MNU, 50 mg/kg) on PNDs 22 and 51 and were euthanized on PND 24 (Ki-67, ER-α and apoptosis indexes or molecular analysis) or PND 180 (tumor assay). TCDD exposure altered the development of the mammary structure while these alterations were partially improved by maternal Res. Two days after first MNU administration, some genes associated with apoptosis were altered in the mammary tissue from the TCDD group (Bax and Caspase 3 down- and Bcl-2 upregulated) but were also partially reestablished by maternal Res. Mammary gland bcl-2 and bcl-xl proteins expression was increased while the apoptosis index was reduced by TCDD exposure but restored by maternal Res. An increase in number of mammary tumors was observed in female offspring from the TCDD group compared to the other groups. The results indicate that most mammary changes induced in female offspring through TCDD exposure or after MNU administrations were reduced by maternal resveratrol treatment.

Effect of Paralympic powerlifting training on sleep and its relationship with training load

Abstract Aim: This study aims to compare the sleep parameters in Paralympic powerlifting athletes during days with and without training, and to analyze the relationship between the training load and sleep on the same day and the relationship between the previous night's sleep and the training load of the following day. Methods: Actigraphy was used to analyze the sleep parameters of 11 Paralympic powerlifting athletes for 14 days (7 days without and with training), whereas Ratings of Perceived Exertion (RPE) analysis was used to assess training load. In addition, the Horne and östberg chronotype questionnaire and the Epworth Sleepiness Scale were applied. Results: Athletes show morning and indifferent chronotype and low daytime sleepiness. We found that on training days, sleep onset latency (SOL) was lower (average 5.3 min faster), whereas total sleep time (TST) and sleep efficiency (SE) were higher (TST averaged 169 min and SE 7% higher) compared to non-training days. In addition, the TST of the night before the training days correlated positively with the RPE of the following day, and the training volume correlated negatively with the SE of the same day. Conclusion: Our findings show that Paralympic powerlifting training had positive effects in increasing TST and SE and decreasing SOL on training days. These results show the positive effects of this type of training in improving sleep in athletes with physical disabilities. In addition, a good night's sleep the day before training can make it possible to put more effort into the next day's training. Therefore, guiding athletes to sleep more before training with more intense loads is recommended.

N-Methyl-d-Aspartate (NMDA) Receptor Blockade Prevents Neuronal Death Induced by Zika Virus Infection.

Zika virus (ZIKV) infection is a global health emergency that causes significant neurodegeneration. Neurodegenerative processes may be exacerbated by N-methyl-d-aspartate receptor (NMDAR)-dependent neuronal excitoxicity. Here, we have exploited the hypothesis that ZIKV-induced neurodegeneration can be rescued by blocking NMDA overstimulation with memantine. Our results show that ZIKV actively replicates in primary neurons and that virus replication is directly associated with massive neuronal cell death. Interestingly, treatment with memantine or other NMDAR blockers, including dizocilpine (MK-801), agmatine sulfate, or ifenprodil, prevents neuronal death without interfering with the ability of ZIKV to replicate in these cells. Moreover, in vivo experiments demonstrate that therapeutic memantine treatment prevents the increase of intraocular pressure (IOP) induced by infection and massively reduces neurodegeneration and microgliosis in the brain of infected mice. Our results indicate that the blockade of NMDARs by memantine provides potent neuroprotective effects against ZIKV-induced neuronal damage, suggesting it could be a viable treatment for patients at risk for ZIKV infection-induced neurodegeneration.IMPORTANCE Zika virus (ZIKV) infection is a global health emergency associated with serious neurological complications, including microcephaly and Guillain-Barré syndrome. Infection of experimental animals with ZIKV causes significant neuronal damage and microgliosis. Treatment with drugs that block NMDARs prevented neuronal damage both in vitro and in vivo These results suggest that overactivation of NMDARs contributes significantly to the neuronal damage induced by ZIKV infection, and this is amenable to inhibition by drug treatment.

Alzheimer's disease: Targeting the Cholinergic System.

Acetylcholine (ACh) has a crucial role in the peripheral and central nervous systems. The enzyme choline acetyltransferase (ChAT) is responsible for synthesizing ACh from acetyl-CoA and choline in the cytoplasm and the vesicular acetylcholine transporter (VAChT) uptakes the neurotransmitter into synaptic vesicles. Following depolarization, ACh undergoes exocytosis reaching the synaptic cleft, where it can bind its receptors, including muscarinic and nicotinic receptors. ACh present at the synaptic cleft is promptly hydrolyzed by the enzyme acetylcholinesterase (AChE), forming acetate and choline, which is recycled into the presynaptic nerve terminal by the high-affinity choline transporter (CHT1). Cholinergic neurons located in the basal forebrain, including the neurons that form the nucleus basalis of Meynert, are severely lost in Alzheimer's disease (AD). AD is the most ordinary cause of dementia affecting 25 million people worldwide. The hallmarks of the disease are the accumulation of neurofibrillary tangles and amyloid plaques. However, there is no real correlation between levels of cortical plaques and AD-related cognitive impairment. Nevertheless, synaptic loss is the principal correlate of disease progression and loss of cholinergic neurons contributes to memory and attention deficits. Thus, drugs that act on the cholinergic system represent a promising option to treat AD patients.

The Phoneutria nigriventer spider toxin, PnTx4-5-5, promotes neuronal survival by blocking NMDA receptors.

Spider toxins are recognized as useful sources of bioactive substances, showing a wide range of pharmacological effects on neurotransmission. Several spider toxins have been identified biochemically and some of them are specific glutamate receptors antagonists. Previous data indicate that PnTx4-5-5, a toxin isolated from the spider Phoneutria nigriventer, inhibits the N-methyl-d-aspartate receptor (NMDAR), with little or no effect on AMPA, kainate or GABA receptors. In agreement with these results, our findings in this study show that PnTx4-5-5 reduces the amplitude of NMDAR-mediated EPSCs in hippocampal slices. It is well established that glutamate-mediated excitotoxic neuronal cell death occurs mainly via NMDAR activation. Thus, we decided to investigate whether PnTx4-5-5 would protect against various cell death insults. For that, we used primary-cultured corticostriatal neurons from wild type (WT) mice, as well as from a mouse model of Huntington's disease, BACHD. Our results showed that PnTx4-5-5 promotes neuroprotection of WT and BACHD neurons under the insult of high levels of glutamate. Moreover, the toxin is also able to protect WT neurons against amyloid ß (Aß) peptide toxicity. These results indicate that the toxin PnTx4-5-5 is a potential neuroprotective drug.

Early diagnosis of prostate cancer by citrate determination in urine with europium-oxytetracycline complex.

Normal prostate tissue contains high levels of citrate. In the presence of prostate cancer, the citrate level is diminished. In this paper we show that it is possible to use europium-oxytetracycline complex as a citrate fluorescent probe and consequently as a prostate cancer probe. We analyzed normal nude male mice urine and urine from nude male mice in which prostate cancer was induced by intraprostatic inoculation of DU145 cells. The urine samples were collected from the animals at the 7th, 14th, 21st, and 35th days after the surgery procedures. The intensity of europium emission at 615 nm in europium-oxytetracycline complex in the presence of citrate increases linearly. The citrate concentrations were determined from a calculated calibration curve. A concentration decrease in malignant prostate urine from the normal (PBS group) urine value from ~8.0 mM to ~2.4 mM (tumor group at 35th day) was found. The obtained results indicated that europium-oxytetracycline provides a significant biomarker for prostate cancer detection with a direct, accurate, noninvasive, and non-enzymatic method for measurement of citrate in biological fluids.

Urea hydrogen peroxide determination in whole blood using europium tetracycline probe.

We introduce the use of a lanthanide complex, tetracycline-europium, for the clinical diagnosis of urea hydrogen peroxide in human whole blood. The values obtained agree with the urea concentration variation verified in 49 patients, including 12 predialysis, 12 peritoneal, and 15 dialysis subjects, and 10 controls. This method is noninvasive and can help in the identification of renal and cardiac diseases.