Calcium pyrophosphate dihydrate crystal deposition in the craniovertebral junction

OBJECT: Calcium pyrophosphate dihydrate (CPPD) deposition is a rare cause of retroodontoid mass lesions in elderly individuals. However, this condition may be severely underdiagnosed if sufficient attention is not paid to imaging characteristics and clinical presentation. The authors sought to evaluate the decision-making process in both the diagnosis and surgical treatment of CPPD. METHODS: A retrospective review of University of Iowa medical records and radiographs accumulated between 1977 and 2006 was performed. The inclusion criterion was histopathological findings consistent with pseudogout at the craniovertebral junction (CVJ). Twenty-one patients with a mean age of 70.3 years and a mean symptom duration prior to presentation of 17.5 months were identified and included in this study. RESULTS: The patients presented most frequently with occipital and neck pain (85%) and numbness or paresthesias (61%). Lower cranial nerve deficits were seen in 29%. Calcification of the mass or transverse ligament was seen on computed tomography in all included patients. Gross-total resection was achieved in all patients: 19 of 21 patients underwent transoral-transpalatopharyngeal resection, with only 16 requiring concomitant dorsal occipital-cervical fusion. The mean follow-up duration was 15 months. Eighteen patients (86%) had improvement or resolution of symptoms after treatment, and 3 were lost to follow-up. CONCLUSIONS: Although rare, CPPD deposition at the CVJ should be suspected on finding calcification of and around the transverse ligament on neuroimaging. Transoral-transpalatopharyngeal resection is preferred to halt the progression of neurological deterioration; dorsal fusion is not always mandatory as concomitant ligamentous calcification and atlantoaxial joint ankylosis may provide added stability.     

Three-dimensional analysis of dentolabial relationships: effect of age and sex in healthy dentition

Morphological changes in three-dimensional (3D) dentolabial relationships during ageing were assessed in healthy individuals. 38 subjects with healthy dentition were analysed. They were divided into a youthful group (21–34 years, mean 26 years, SD 4) and an older group (45–65 years, mean 53 years, SD 5). Stone labial and dental models were made, digitized and 3D virtual reproductions of dentolabial morphology were obtained. From the digital reconstructions, the relative positions of the labial commissure and of the maxillary dental clinical crowns in the vertical direction were obtained. Sex and age effects were compared using two-way analysis of variance. Lip position relative to the teeth was significantly different in youthful and older subjects (P < 0.01). No statistically significant effects of sex in dentolabial relationship were demonstrated, but a sex × age effect was found in the anterior labial segments (P < 0.05). The perioral soft tissues drop down in older subjects and the soft tissue descends on the entire labial arch. These differences may help the clinician when estimating, planning and evaluating surgical, orthodontic and prosthetic treatments.     

A single injection of pregabalin induces short- and long-term beneficial effects on fear memory and anxiety-like behavior in rats with experimental type-1 diabetes mellitus

Metabolic Brain Disease - Anxiety Disorders and Posttraumatic Stress Disorders (PTSD) associated with type-1 diabetes mellitus (T1DM) are increasingly common comorbidities and the treatment is...     

Muscular adaptations to training programs using the Nordic hamstring exercise or the stiff-leg deadlift in rugby players

Sport Sciences for Health - Muscular responses to training programs with the Nordic hamstring exercise (NHE) have been widely investigated to understand its preventive effects on muscle strain...     

Reduced Motivation in Perinatal Fluoxetine-Treated Mice: A Hypodopaminergic Phenotype

Early life is a sensitive period, in which enhanced neural plasticity allows the developing brain to adapt to its environment. This plasticity can also be a risk factor in which maladaptive development can lead to long-lasting behavioral deficits. Here, we test how early-life exposure to the selective-serotonin-reuptake-inhibitor (SSRI), fluoxetine, affects motivation, and dopaminergic signaling in adulthood. We show for the first time that mice exposed to fluoxetine in the early postnatal period exhibit a reduction in effort-related motivation. These mice also show blunted responses to amphetamine and reduced dopaminergic activation in a sucrose reward task. Interestingly, we find that the reduction in motivation can be rescued in the adult by administering bupropion, a dopamine-norepinephrine reuptake inhibitor used as an antidepressant and a smoke cessation aid but not by fluoxetine. Taken together, our studies highlight the effects of early postnatal exposure of fluoxetine on motivation and demonstrate the involvement of the dopaminergic system in this process.SIGNIFICANCE STATEMENT The developmental period is characterized by enhanced plasticity. During this period, environmental factors have the potential to lead to enduring behavioral changes. Here, we show that exposure to the SSRI fluoxetine during a restricted period in early life leads to a reduction in adult motivation. We further show that this reduction is associated with decreased dopaminergic responsivity. Finally, we show that motivational deficits induced by early-life fluoxetine exposure can be rescued by adult administration of bupropion but not by fluoxetine.     

ABO blood group in Amerindians from Brazilian Amazon

Background : The Parakanã is a group of Indians with cultural similarities to the extinct Tupi group. They are an isolated native population from East Brazilian Amazon. A number of different O alleles have been found at the blood group ABO locus in populations of several ethnic origins (Caucasians, Blacks, Amerindians). Aim : The present study describes the ABO blood group polymorphism gene of the Parakanã Indians. The Amerindian group was carefully selected for racial background. Subject and methods : The blood group polymorphism was analysed in genomic DNA from 62 Parakanã Indians. We determined the 261G deletion, the T646A and C771T mutations described in O 1variant and the G542A substitution, using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Results : All Amerindians studied were homozygous for the 261G deletion. The frequencies of the T646A and C771T mutations in Parakanãs (0.65) were lower than that observed in Kayapo, Yanomama and Arara Indians (0.91) ( &#104 2 = 18.24; p-v < 0.001. The G542A substitution in Parakanãs was also lower (0.22) than in other tribes (0.42) ( &#104 2 = 9.73; p-v = 0.001). Conclusions : The different O alleles including the G542A mutation are not distributed homogeneously among all Amazonian Amerindians. Our results are in agreement with other genetic markers studied previously in Parakanã Indians, whose distinct genetic pattern differs from Europeans and even from other Amerindians.     

Edentulousness in relation to remodeling of the gonial angles and incisures in dentate and edentate mandibles: morphometric study using the Image J software

Purpose

The human mandible is subject to stimuli during its growth phase and also in adulthood. One of these stimuli may be absence of teeth, which gives rise to mandibular remodeling. Morphological changes may occur in different areas of this bone, such as in the gonial, condylar and ramus regions.

Objective

To investigate the influence of edentulousness on remodeling of the gonial angle of the mandible and the angle formed by the mandibular incisure.

Materials and method

Eighty-five dry mandibles from adults were examined: 42 from males and 43 from females. The mandibles were photographed using a camera coupled to a static support that was positioned 20 cm from the object to be photographed. The images were digitized and transferred to the Image J 1.42q software, in which the gonial angle of the mandible and the mandibular incisure angle were measured.

Results

There were no differences in the mandibular and mandibular incisure angles in relation to presence or absence of teeth, or between the right and left sides. The mandibular incisure angle was greater in the women.

Conclusion

Edentulousness did not cause remodeling of the gonial angle of the mandible or in the mandibular incisure angle.     

Rutin-modified silver nanoparticles as a chromogenic probe for the selective detection of Fe3+ in aqueous medium

The development of nanoprobes for selective detection of metal ions in solution has attracted great attention due to their impact on living organisms. As a contribution to this field, this paper reports the synthesis of silver nanoparticles modified with rutin in the presence of ascorbic acid and their successful use as a chromogenic probe for the selective detection of Fe³⁺ in aqueous solution. Limits of detection and quantification were found to be 17 nmol L⁻¹ and 56 nmol L⁻¹, respectively. The sensing ability is proposed to proceed via an iron-induced nanoparticle growth/aggregation mechanism. A practical approach using image analysis for quantification of Fe³⁺ is also described.

The use of rutin-modified silver nanoparticles for selective detection and sensitive quantification of Fe³⁺ in aqueous solution is described.

Metal ions are key species in nature due to their essential functions in living organisms.^1,2 On the other hand, heavy metals as well as essential metals at abnormally high levels are toxic.² Iron, for instance, in addition to its popular use in industry and construction, is essential to the human body and active in biological processes. Although the trivalent form of iron is particularly important for oxygen transport in blood and the mitochondrial respiratory chain, high levels of this cation are associated with important pathologies.^3,4 The detection of metal ions in aqueous solution is traditionally performed by methods including atomic absorption spectrometry,⁵ electrochemical measurements,^6,7 and inductively coupled plasma techniques,⁸ among others. However, these techniques have important drawbacks, notably the need for sophisticated instrumentation, in addition to being time-consuming and requiring laborious procedures. To overcome these issues, the development of chromogenic and fluorogenic chemosensors for the selective detection of metal-targets has attracted great attention, especially due to the possibility of fast, sensitive and non-expensive analysis.^9,10 In the last decade, nanoscaled materials have been reported as selective probes for metal ions, including Fe³⁺.^11–24Silver nanoparticles (AgNPs) are of particular interest because of the affordable price of starting materials, ease of controlling size and morphology, possibility to functionalize their surface with organic molecules, and optical properties that enable detection of a variety of analytes via simple UV-vis spectroscopy and digital image analysis. Furthermore, applications of AgNPs are also biotechnologically relevant due to the possibility of green synthetic protocols, including the use of plant extracts,²⁵ natural sources,²⁶ glycerol,²⁷ among others.Flavonoids are secondary metabolites naturally found in fruits and other vegetables with relevant roles due to their nutritional, pharmaceutical and medicinal properties.²⁸ Because of their adequate structural features, flavonoids are candidates to be employed in the synthesis of AgNPs.²⁶ Rutin (RU), a sugar-based flavonoid, may be employed as reducing agent in the synthesis of AgNPs along with a stabilizer such as polyvinylpyrrolidone (PVP)²⁶ or used as crude plant extract component.^29,30This paper reports the use of RU-modified AgNPs (RU-AgNPs) as a chromogenic probe for Fe³⁺ in aqueous medium in the presence of ascorbic acid (AA). Sensing ability of RU-AgNPs for the selective detection of Fe³⁺ toward other metal cations was investigated with UV-vis spectroscopy analysis. These data and transmission electronic microscopy (TEM) results allowed a mechanistic proposal involved in the selective detection of Fe³⁺ by RU-AgNPs. Furthermore, a practical approach based on correlation of images of solutions obtained with a conventional smartphone and chemometrics was employed for a simpler quantification of Fe³⁺ in aqueous medium.Initially, the order of reagent combination was investigated in the synthesis of RU-AgNPs. Concentration of RU ranged from 0.10 to 0.50 mmol L⁻¹, while concentrations of other components were fixed at 0.20 mmol L⁻¹ AgNO₃, 0.10 mmol L⁻¹ AA and 0.10 M NaOH. Water was used as solvent in all cases. Narrower surface plasmon resonance (SPR) bands were obtained from adding a solution of AA and NaOH to a solution containing RU and AgNO₃ (Fig. 1a) against the addition of RU, AA, and NaOH to AgNO₃ solution (Fig. S1a – ESI^†), or the addition of RU and NaOH to a solution of AA and AgNO₃ (Fig. S1b^†). RU-AgNPs obtained from the condition presented in Fig. 1a are small (4.1 nm average diameter) and considerably polydisperse (standard deviation of 4.7 nm), however, presenting only one population (Fig. 1b and S2^†). A study of the influence of RU concentration (0.10 to 0.50 mmol L⁻¹) on the stability of RU-AgNPs over time indicated that 0.10 mmol L⁻¹ RU generates more stable RU-AgNPs (Fig. S3^†). Next, a study on the influence of pH indicated that RU-AgNPs are only stable under strong alkaline conditions (pH 12.5 or higher) (Fig. S4^†).Open in a separate windowFig. 1(a) UV-vis analysis of RU-AgNPs under strong alkaline condition (pH > 12.5) based on the order of adding reagents (RU, 0.10 to 0.50 mmol L⁻¹; AgNO₃, 0.20 mmol L⁻¹; AA, 0.10 mmol L⁻¹; NaOH, 0.10 mmol L⁻¹); (b) TEM image of RU-AgNPs under the selected condition.The ability of RU-AgNPs to sense metal cations was investigated by both naked-eye and UV-vis spectroscopy analysis (Fig. 2). The separate addition of 10 μmol L⁻¹ of several metal cations (Fe³⁺, Co²⁺, Zn²⁺, Sr²⁺, Cu²⁺. Al³⁺, Ba²⁺, Cd²⁺, Pb²⁺, Ni²⁺, Mg²⁺, Hg²⁺, Cu⁺ and Cr³⁺) to solutions of RU-AgNPs (prepared according to Fig. 1a) indicated that only Fe³⁺ induces a significant colorimetric change in the final aspect of solution after 50 minutes (Fig. 2a).Open in a separate windowFig. 2Naked-eye (a) and UV-vis (b) analysis of RU-AgNPs in absence (control, C) and presence of 10 μmol L⁻¹ of selected metal cations (Fe³⁺, Co²⁺, Zn²⁺, Sr²⁺, Cu²⁺. Al³⁺, Ba²⁺, Cd²⁺, Pb²⁺, Ni²⁺, Mg²⁺, Hg²⁺, Cu⁺ and Cr³⁺) after 50 min; (c) calibration curve obtained by the addition of different amounts (0 to 10 μmol L⁻¹) of Fe³⁺ to solutions of RU-AgNPs; (d) TEM image of RU-AgNPs after addition of Fe³⁺ (10 μmol L⁻¹). In all experiments, RU-AgNPs were prepared in the presence of ascorbic acid.The results presented in Fig. 2a are consistent with the UV-vis spectroscopy analysis (Fig. 2b). Co²⁺ ions also induce some change in the system, however at a considerably smaller extension than Fe³⁺. In this study, AA played a crucial role in the selective detection of Fe³⁺ by the referred nanoprobe. In the absence of AA, Co²⁺ (mainly) as well as other cations induce stronger colorimetric and spectral changes (Fig. S5a and b,^† respectively) in the analysis of solutions of RU-AgNPs when compared to the system containing AA. This selectivity may arise from two possible reasons: (i) preservation of RU by avoiding its oxidation in the reduction of Ag⁺ ions; (ii) coordination of ascorbate anion to cations other than Fe³⁺.Interaction of RU-AgNPs and Fe³⁺ (10 μmol L⁻¹) stabilizes after approximately 40 minutes (Fig. S6^†). Next, a calibration curve was built from the direct relationship between the absorbance at 396 nm and the concentration of Fe³⁺ (Fig. 2c), presenting a good correlation (R² = 0.9929). The limits of detection and quantification were found to be 17 nmol L⁻¹ and 56 nmol L⁻¹, respectively, which is very satisfactory.^13,14 The influence of other cations in the detection of Fe³⁺ was investigated by UV-vis spectroscopy. Fig. S7^† clearly demonstrates that there are only small changes when a second cation (30 μmol L⁻¹) is added together with Fe³⁺ to the RU-AgNPs solution.Mechanistically, the detection of Fe³⁺ by RU-AgNPs in aqueous medium proceeds via a growth/aggregation-combined process. This proposal is first evidenced by UV-vis analysis due the suppression of SPR band (Fig. 2b), a behavior consistent with the literature.^31,32 Interestingly, TEM analysis clearly shows a growth in AgNPs size after addition of Fe³⁺ to the solution (Fig. 2d), resulting in a final single AgNPs population with average diameter of 14.7 nm ± 8.9 nm. Due to the strong alkaline medium, the main specie responsible for the behavior of NPs is likely to be Fe(OH)₃. A schematic illustration of the mechanism involving aggregation of RU-AgNPs induced by the addition of Fe³⁺ is presented in Fig. 3. AgNPs are initially formed by adsorption of anionic RU to the silver surface via deprotonated 5-hydroxychromen-4-one moiety. This is supported by the literature³³ and confirmed by alteration in the 1800–1500 cm⁻¹ region of the RU infrared spectra before and after coordination with silver (Fig. S9^†). Afterwards, the addition of Fe³⁺ induces the formation of a coordination complex through an anionic catechol group, in which at least 2 : 1 ligand–Fe³⁺ stoichiometry is required for an aggregated effect.Open in a separate windowFig. 3Mechanistic proposal for growth/aggregation of RU-AgNPs in the presence of Fe³⁺. Insert: binding model for RU-AgNPs.Due to increasing interest in image processing as an analytical tool for many purposes,^34,35 Multiple Linear Regression was employed to verify the capacity of the RU-AgNPs to probe Fe³⁺ standards at distinct concentrations, as presented in Fig. 4. The curve was obtained by plotting the color absorbances RGB-based values versus the concentrations of Fe³⁺ standards after RU-AgNPs interaction. Predicted iron is a vector based on RGB values that were then extracted from the filtered images and inserted in the equation described by Beer–Lambert law in order to generate the absorbances for the construction of the analytical curve. A linear behavior between the predicted response and the measured concentrations was observed (R² = 0.9806).Open in a separate windowFig. 4Calibration curve for Fe³⁺ analysis showing the predicted iron (RGB) vs. iron(iii) concentration (1 to 8 μmol L⁻¹). Adjusted R² = 0.9806.Regression coefficients of the calibration model (using the R, G and B channels simultaneously) obtained by MLR method are shown in eqn (1):[Fe³⁺] = 44.5R − 4.9G − 16.4B + 5.11where Fe³⁺ concentration is the dependent variable (Predicted Iron), 5.1 is the intercept (β₀), 44.5, −4.9 and −16.4 are the regression coefficients of the independent variables (R, G and B channels, respectively).It is possible to observe an interesting performance of the method using the three RGB color channels allied with MLR to quantify the Fe³⁺ content, which presented reasonable deviations in its responses considering that it is simple and low-cost. The good linearity is similar to other colorimetric methods such as sodium determination in seawater and coconut water (R² > 0.91) by Moraes and coauthors,³⁶ or iron(ii) in simulated seawater (R² = 0.9993) by Gasparotto et al.³⁷Second order regression was applied to the dataset to obtain a better adjustment, resulting in an adjusted R-squared of 0.9955. RGB values were then inserted in eqn (2) in order to generate the construction of the correlation:[Fe³⁺] = 14.4R + 30.7G − 23.4B − 398RG − 348RB − 0.8BG − 978R² + 695G² + 26.9B² + 4.52This paper reports the use of AgNPs functionalized with RU as nanoprobes for selective detection and sensitive quantification of Fe³⁺ in aqueous solution. The synthesis of RU-AgNPs is reproducible, easily performed and requires no stabilizer agent other than RU. AA has a crucial role in the selectivity by either the avoidance of oxidation of RU by silver and/or coordination of ascorbate with other cations. The literature brings relevant examples of chromogenic and fluorogenic chemosensors for selective detection of Fe³⁺ in solution. Many of these artificial organic receptors present high selectivity and relevant limits of detection, requiring, however, very specific reagents and laborious synthetic procedures.^38–41 Metal-based nanoparticles have emerged as potential probes for detection of Fe³⁺.^11–16 Although effective in Fe³⁺ sensing, the synthesis of these nanoprobes require some toxic reagents, such as NaBH₄ or PVP, use plant extracts, which may lead to some drawbacks, such as the understanding of the sensing mechanism. In contrast, our method is based on commercially available, nontoxic, low-cost reagents. Fe³⁺ sensing performed satisfactorily in the 1–10 μmol L⁻¹ range, and the limit of detection obtained with this method (17 nmol L⁻¹) is comparable to the most sensitive methods reported in literature. A mechanism for the detection of Fe³⁺ by RU-AgNPs involves a combined growth/aggregation of the NPs. There is a still limited number of nanoscaled systems reported as being selective and sensitive in the detection of Fe³⁺, which reinforces the relevance of the method reported herein. The linearity range obtained by both UV-vis spectroscopy and image analysis comprises the maximum of residual Fe³⁺ in drinking water according to the European and US legislations.^15,42     

Non-mechanical traumatic gas gangrene: forgotten but not gone

We report a case of gas gangrene (GG) in a non-diabetic HIV seronegative man who died within 60 hours following an intramuscular injection in rural India. The occurrence of GG after intramuscular injection is rare and only a few cases have been reported in the published literature.