Effects of Cadmium on the Rat Salivary Glands, During Lactation

Cadmium (Cd) in air, drinking water and food has the potential to affect the health of people, mainly those who live in highly industrialized regions. Cd affects placental function, can cross the placental barrier and directly modify fetal development. Once the organism is particularly susceptible to the exposition to the Cd during the perinatal period, and that this metal can be excreted in the milk, the aim of the present work was to study the effects of the constant exposition to drinkable water containing low levels of Cd during the lactation, on the salivary glands of the rat. Female rats received ad libitum drinking water containing 300mg/l of CdCl2 throughout the whole lactation. Control animals received a similar volume of water without Cd. Lactant rats (21 day old) were killed by lethal dose of anesthetic. The salivary glands were separated, fixed in ""alfac"" solution for 24 h, and serially sectioned. The 6 mu m thick sections were stained with hematoxylin and eosin. Nuclear glandular parameters were estimated, as well as cytoplasm and cell volume, nucleus/cytoplasm ratio, number and surface density, diameters and cell thickness. Mean body weight was 34.86 g for the control group and 18.56 g for the Cd-treated group. Histologically, the glandular acini were significantly smaller, the gland ducts were similar in both groups studied. The connective tissue was more abundant. In conclusion, the salivary glands (submandibular, parotid and sublingual) showed retarded growth after Cd intoxication.

Isolation and characterization of four type 2 ribosome inactivating pulchellin isoforms from Abrus pulchellus seeds

Abrus pulchellus seeds contain at least seven closely related and highly toxic type 2 ribosome-inactivating pulchellins, each consisting of a toxic A-chain linked to a sugar binding B-chain. In the present study, four pulchellin isoforms (termed P I, P II, P III and P IV) were isolated by affinity, ion exchange and chromatofocusing chromatographies, and investigated with respect to toxicity and sugar binding specificity. Half maximal inhibitory concentration and median lethal dose values indicate that P I and P II have similar toxicities and that both are more toxic to cultured HeLa cells and mice than P III and P IV. Interestingly, the secondary structural characteristics and sugar binding properties of the respective pairs of isoforms correlate well with the two toxicity levels, in that P I/P II and P III/P IV form two specific subgroups. From the deduced amino acids sequences of the four isoforms, it is clear that the highest similarity within each subgroup is found to occur within domain 2 of the B-chains, suggesting that the disparity in toxicity levels might be attributed to subtle differences in B-chain-mediated cell surface interactions that precede and determine toxin uptake pathways.

Determination of fluoroacetate and fluoride in blood serum by capillary zone electrophoresis using capacitively coupled contactless conductivity detection

Fluoroacetate is a highly toxic species naturally found in plants and in commercial products (compound 1080) for population control of several undesirable animal species. However, it is non-selective and toxic to many other animals including humans, and thus its detection is very important for forensic purposes. This paper presents a sensitive and fast method for the determination of fluoroacetate in blood serum using capillary electrophoresis with capacitively coupled contactless conductivity detection. Serum blood samples were treated with ethanol to remove proteins. The samples were analyzed in BGE containing 15 mmol/L histidine and 30 mmol/L gluconic acid (pH 3.85). The calibration curve was linear up to 75 mu mol/L (R(2) = 0.9995 for N = 12). The detection limit in the blood serum was 0.15 mg/kg, which is smaller than the lethal dose for humans and other animals. Fluoride, a metabolite of the fluoroacetate defluorination, could also be detected for levels greater than 20 mu mol/L, when polybrene was used for reversion of the EOF. CTAB and didecyldimethylammonium bromide are not useful for this task because of the severe reduction of the fluoride level. However, no interference was observed for fluoroacetate.

Is a lower dose of vitamin D supplementation enough to increase 25(OH)D status in a sunny country?

Calcium and vitamin D are essential nutrients for bone metabolism Vitamin D can either be obtained from dietary sources or cutaneous synthesis. The study was conducted in subtropic weather; therefore, some might believe that the levels of solar radiation would be sufficient in this area. To evaluate calcium and vitamin D supplementation in postmenopausal women with osteoporosis living in a sunny country. A 3-month controlled clinical trial with 64 postmenopausal women with osteoporosis, mean age 62 +/- A 8 years. They were randomly assigned to either the supplement group, who received 1,200 mg of calcium carbonate and 400 IU (10 mu g) of vitamin D(3,) or the control group. Dietary intake assessment was performed, bone mineral density and body composition were measured, and biochemical markers of bone metabolism were analyzed. Considering all participants at baseline, serum vitamin D was under 75 nmol/l in 91.4% of the participants. The concentration of serum 25(OH)D increased significantly (p = 0.023) after 3 months of supplementation from 46.67 +/- A 13.97 to 59.47 +/- A 17.50 nmol/l. However, the dose given was limited in effect, and 86.2% of the supplement group did not reach optimal levels of 25(OH)D. Parathyroid hormone was elevated in 22.4% of the study group. After the intervention period, mean parathyroid hormone tended to decrease in the supplement group (p = 0.063). The dose given (400 IU/day) was not enough to achieve 25(OH)D concentration, considered optimal for bone health.

Higher evening antiepileptic drug dose for nocturnal and early-morning seizures

We describe 17 children with nocturnal or early-morning seizures who were switched to a proportionally higher evening dose of antiepileptic drugs and were retrospectively reviewed for seizure outcome and side effects. Of 10 children with unknown etiology, clinical presentation was consistent with nocturnal frontal lobe epilepsy (NFLE) in 5 and benign epilepsy with centrotemporal spikes (BECTS) in 3. After a mean follow-up of 5.3 months, 15 patients were classified as responders: 11 of these became seizure free (5 NFLE, 1 BECTS, 5 with structural lesions) and 4 (2 BECTS, 2 with structural lesions) experienced 75-90% reductions in seizures. Among two nonresponders, seizures in one had failed to resolve with epilepsy surgery. Nine subjects (53%) received monotherapy after dose modification, and none presented with worsening of seizures. Two complained of transient side effects (fatigue/somnolence). Differential dosing led to seizure freedom in 64.7% (11/17) of patients, and 88.2% (15/17) experienced >= 50% reductions in seizures. (C) 2010 Elsevier Inc. All rights reserved.

FT-IR spectroscopy assessment of aesthetic dental materials irradiated with low-dose therapeutic ionizing radiation

The aim of the present study was to evaluate the effects of low-dose therapeutic ionizing radiation on different aesthetic dental materials. Forty five specimens (n = 45) of three different aesthetic restorative materials were prepared and randomly divided into five groups: G1 (control group); G2, G3, G4, G5 experimental groups irradiated respectively with 0.25, 0.50, 0.75, and 1.00 Gy of gamma radiation by the (60)Co teletherapy machine. Chemical analyses were performed using a FT-IR Nicolet 520 spectrophotometer with reflectance diffuse technique. Even a minimal exposition at ionizing radiation in therapeutic doses can provide chemical changes on light-cured composite resins. The three studied restorative materials showed changes after exposure at gamma radiation, however the increase of the radiation dose did not contribute to an increase in this effect.

In vitro tests to establish LC(50) and discriminating concentrations for fipronil against Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) and their standardization

Laboratory test was carried out on larvae and adults of the cattle tick, Rhipicephalus (Boophilus) microplus, to determine fipronil toxicity. Adult immersion test (AIT, N = 26), larval immersion test (LIT, N = 71) and larval packet test (LPT, N = 41) were standardized using susceptible strain (Mozo). Dose-response curves were compared with a fipronil resistant strain. Four variables were analyzed from AIT results: mortality, weight of eggs on day 7 and on day 14, index of fertility, and index of fecundity. For larval test, dose mortality curves were analyzed. In spite of the high LC(50) variability, all variables determined for AIT were appropriate to discriminate both strains. AIT and LIT had more sensitivity than LPT, with larger resistance factors. It was used two times LC(99.9) as discriminating doses (DCs) following FAO suggestion. For mortality by AIT, LIT and LPT the DCs were estimated: 4.98 ppm, 7.64 ppm and 2365.8 ppm, respectively, for Mozo strain. DCs mortality values estimated for resistant strain by AIT, LIT and LPT were: 6.96 x 10(5) ppm, 343.26 ppm and 5.7 x 10(3) ppm, respectively and their respective resistant factors were: 202.4, 5.36 and 1.52. Protocols for AIT, LIT and LPT have been presented in this paper. (C) 2009 Elsevier B.V. All rights reserved.

Determination of the susceptibility of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) to ivermectin and fipronil by Larval Immersion Test (LIT) in Uruguay

Rhipicephalus (Boophilus) microplus is an important cattle pest in Uruguay, and the law regulates its control. It is resistant to organophosphates, synthetic pyrethroids and, as recently discovered, to fipronil. Resistance to macrocyclic lactones (MLs) and amitraz have not been documented; however, veterinarians and farmers have reported treatment failures. The objective of the present work was to study the susceptibility of cattle tick strains from different Uruguayan counties to ivermectin (IVM) and fipronil by using the Larval Immersion Test (LIT). The Mozo strain was used as the susceptible reference strain. From 2007 to 2009, twenty-eight tick populations were collected from different cattle farms with and without history of IVM or fipronil use. A probit analysis estimated dose-mortality regressions, lethal concentrations (LC), and confidence intervals. The resistance ratio (RR) was determined at the LC(50) and LC(90) estimates. To classify a tick population in relation to resistance, three categories based on a statistical analysis of LC and RR between field populations and Mozo strains were defined: susceptible (no differences), incipient resistance (differences and RR(50) < 2) and resistant (differences and RR(50) >= 2). Eighteen field populations were tested with IVM and five of them presented a RR(50) range between 1.35 and 1.98 and the LC(50/90), which is statistically different from the Mozo strain (incipient resistance). However, the RR(90) increases >= 2 in four of the populations, confirming that tick resistance to IVM is emergent. The low RR values obtained could be a result of a low frequency of treatments with IVM. Twenty-seven tick populations were tested with fipronil and six were diagnosed as resistant according to the LIT. Cross-resistance was not observed between fipronil and IVM on these tick populations. The current study presents different R. (B.) microplus populations with an incipient resistance to IVM, and indicates that the fipronil tick resistance is restricted to certain areas in Uruguay. (c) 2011 Elsevier B.V. All rights reserved.

Experimental Chemotherapy against Trypanosoma cruzi Infection Using Ruthenium Nitric Oxide Donors

The ruthenium NO donors of the group trans-[Ru(NO)(NH(3))(4)L](n+), where the ligand (L) is N-heterocyclic H(2)O, SO(3)(2 -), or triethyl phosphite, are able to lyse Trypanosoma cruzi in vitro and in vivo. Using half-maximal (50%) inhibitory concentrations against bloodstream trypomastigotes (IC(50)(try)) and cytotoxicity data on mammalian V-79 cells (IC(50)(V79)), the in vitro therapeutic indices (TIs) (IC(50)(V79)/IC(50)(try)) for these compounds were calculated. Compounds that exhibited an in vitro TI of >= 10 and trypanocidal activity against both epimastigotes and trypomastigotes with an IC(50)(try/epi) of <= 100 mu M were assayed in a mouse model for acute Chagas` disease, using two different routes (intraperitoneal and oral) for drug administration. A dose-effect relationship was observed, and from that, the ideal dose of 400 nmol/kg of body weight for both trans-[Ru(NO)(NH(3))(4)isn](BF(4))(3) (isn, isonicotinamide) and trans-[Ru(NO)(NH3) 4imN](BF4) 3 (imN, imidazole) and median (50%) effective doses (ED50) of 86 and 190 nmol/kg, respectively, were then calculated. Since the 50% lethal doses (LD(50)) for both compounds are higher than 125 mu mol/kg, the in vivo TIs (LD(50)/ED(50)) of the compounds are 1,453 for trans-[Ru(NO)(NH(3))(4)isn](BF(4))(3) and 658 for trans-[Ru(NO)(NH(3))(4)imN](BF(4))(3). Although these compounds exhibit a marked trypanocidal activity and are able to react with cysteine, they exhibit very low activity in T. cruzi -glycosomal glyceraldehyde-3-phosphate dehydrogenase tests, suggesting that this enzyme is not their target. The trans-[Ru(NO)(NH(3))(4)isn](BF(4))(3) and trans-[Ru(NO)(NH(3))(4)imN](BF(4))(3) compounds are able to eliminate amastigote nests in myocardium tissue at 400-nmol/kg doses and ensure the survival of all infected mice, thus opening a novel set of therapies to try against trypanosomatids.