Evaluation of bone texture imaging parameters on panoramic radiographs of patients with Sheehan's syndrome: a STROBE-compliant case-control study

Sheehan's syndrome (SHS) is a rare condition related to the risk of osteoporosis and evaluation of bone texture imaging features on panoramic radiographs would be suitable for this condition, which was the aim of the present study. Fractal dimension, lacunarity, and trabecular morphologic aspects were significantly altered in these patients.

INTRODUCTION

SHS is an important public health problem particularly in developing countries. It is characterized as postpartum hypopituitarism secondary to obstetric complications-related ischemic pituitary necrosis that shows significant systemic metabolic repercussions. Thus, this study aimed to evaluate bone texture parameters in digital panoramic radiographs of patients with SHS.

METHODS

A case-control study was conducted with 30 SHS patients from an Endocrinology and Diabetology Service of reference in Brazil, and 30 age- and sex-matched healthy controls. A custom computer program measured fractal dimension, lacunarity, and some morphologic features in the following mandibular regions of interest (50 × 50 pixels): below the mental foramen (F1), between the first and second molars (M1), and at the center of the mandibular ramus (R1).

RESULTS

The fractal analysis showed a statistically significant difference between the studied groups in all regions of interest. The fractal dimension in F1 (p = 0.016), M1 (p = 0.043), and R1 (p = 0.028) was significantly lower in SHS group, as well as lacunarity in R1 (p = 0.008). Additionally, several morphologic features were statistically significant in the SHS group (p < 0.05).

CONCLUSION

Therefore, individuals with SHS showed altered imaging texture parameters on panoramic radiographs, which reflect a smaller spatial organization of the bone trabeculae and, possibly, a state of reduced mineral bone density.

Brain infusion of α-synuclein oligomers induces motor and non-motor Parkinson's disease-like symptoms in mice

Parkinson's disease (PD) is characterized by motor dysfunction, which is preceded by a number of non-motor symptoms including olfactory deficits. Aggregation of α-synuclein (α-syn) gives rise to Lewy bodies in dopaminergic neurons and is thought to play a central role in PD pathology. However, whether amyloid fibrils or soluble oligomers of α-syn are the main neurotoxic species in PD remains controversial. Here, we performed a single intracerebroventricular (i.c.v.) infusion of α-syn oligomers (α-SYOs) in mice and evaluated motor and non-motor symptoms. Familiar bedding and vanillin essence discrimination tasks showed that α-SYOs impaired olfactory performance of mice, and decreased TH and dopamine levels in the olfactory bulb early after infusion. The olfactory deficit persisted until 45days post-infusion (dpi). α- SYO-infused mice behaved normally in the object recognition and forced swim tests, but showed increased anxiety-like behavior in the open field and elevated plus maze tests 20 dpi. Finally, administration of α-SYOs induced late motor impairment in the pole test and rotarod paradigms, along with reduced TH and dopamine content in the caudate putamen, 45 dpi. Reduced number of TH-positive cells was also seen in the substantia nigra of α-SYO-injected mice compared to control. In conclusion, i.c.v. infusion of α-SYOs recapitulated some of PD-associated non-motor symptoms, such as increased anxiety and olfactory dysfunction, but failed to recapitulate memory impairment and depressive-like behavior typical of the disease. Moreover, α-SYOs i.c.v. administration induced motor deficits and loss of TH and dopamine levels, key features of PD. Results point to α-syn oligomers as the proximal neurotoxins responsible for early non-motor and motor deficits in PD and suggest that the i.c.v. infusion model characterized here may comprise a useful tool for identification of PD novel therapeutic targets and drug screening.

Vertical stratification and effect of petiole and dry leaf size on arthropod feeding guilds in Cecropia pachystachya(Urticaceae)

AbstractThis study aimed to test for vertical stratification and the effects of dry leaf size on herbivore and predator arthropods and petiole length on insect borers in Cecropia pachystachya. The leaves were sampled in three strata: attached to the plant, suspended on the vegetation and on the ground. We detected vertical stratification only in the guild of predator arthropods associated with dry leaves, with lower richness and abundance in the attached stratum. In addition, larger leaves positively affected the insect herbivore fauna, whereas the richness and abundance of insect borers increased with petiole length. The greater isolation of leaves attached to trees relative to the surrounding vegetation likely creates greater difficulty for dispersal and colonization by non-winged predators such as spiders. Larger dry leaves provide more shelter against predators and climate variations for insect herbivores. Moreover, larger petioles increase the availability of resources and nesting sites for insect borers. These results are consistent with other studies that found a similarity in the structure of feeding guilds across vertical strata and with studies that showed an increase in species richness and abundance of free-feeding insect herbivores with increasing structural complexity of their host.

Toxicological Evaluation of Anti-Scrapie Trimethoxychalcones and Oxadiazoles

An altered form of the cellular prion protein, the PrPScor PrPRes, is implicated in the occurrence of the still untreatable transmissible spongiform encephalopathies. We have previously synthesized and characterized aromatic compounds that inhibit protease-resistant prion protein (PrPRes) accumulation in scrapie-infected cells. These compounds belong to different chemical classes, including acylhydrazones, chalcones and oxadiazoles. Some of the active compounds were non-toxic to neuroblastoma cells in culture and seem to possess drugable properties, since they are in agreement with the Lipinski´s rule of 5 and present desirable pharmacokinetic profiles as predicted in silico. Before the evaluation of the in vivo efficacy of the aromatic compounds in scrapie-infected mice, safety assessment in healthy mice is needed. Here we used Swiss mice to evaluate the acute toxicity profile of the six most promising anti-prionic compounds, the 2,4,5-trimethoxychalcones (J1, J8, J20 and J35) and the 1,3,4-oxadiazoles (Y13 and Y17). One single oral administration (300 mg/kg) of J1, J8, J20, J35, Y13 and Y17 or repeated intraperitoneal administration (10 mg/kg, 3 times a week, for 4 weeks) of J1, J8 and J35, did not elicit toxicity in mice. We strongly believe that the investigated trimethoxychalcones and oxadiazoles are interesting compounds to be further analyzed in vivo against prion diseases.

Influence of the artefact reduction algorithm of Picasso Trio CBCT system on the diagnosis of vertical root fractures in teeth with metal posts

OBJECTIVES

To assess the influence of the artefact reduction algorithm (AR) available on the Picasso Trio 3D(®) imaging system (Vatech, Hwaseong, Republic of Korea) on image quality [greyscale values, contrast-to-noise ratio (CNR) and artefact formation] and diagnosis of vertical root fractures (VRFs) in the teeth with intracanal metal posts.

METHODS

30 uniradicular teeth had their crowns removed and their roots endodontically treated to receive intracanal metal posts. In 20 teeth, both complete (n = 10) and incomplete (n = 10) VRFs were created. Each tooth was scanned twice, with and without AR activation. The mean and variation of greyscale values, as well as CNR, were calculated for all images. Subsequently, an evaluator compared the amount of artefact (cupping, white streaks and dark bands) in all images. Five evaluators rated for VRF presence using a five-point scale.

RESULTS

Mean greyscale values and CNR were significantly decreased in images acquired with the AR. The usage of the algorithm promoted an overall reduction of image artefacts. Regarding the diagnosis of complete and incomplete VRFs, the use of the AR had an overall negative impact on specificity and accuracy.

CONCLUSIONS

While indeed reducing artefact formation, the use of the AR, instead of improving the impact on the diagnosis of VRFs in teeth with intracanal metal posts, had a negative impact on the diagnosis.

Alzheimer-associated Aβ oligomers impact the central nervous system to induce peripheral metabolic deregulation

Alzheimer's disease (AD) is associated with peripheral metabolic disorders. Clinical/epidemiological data indicate increased risk of diabetes in AD patients. Here, we show that intracerebroventricular infusion of AD-associated Aβ oligomers (AβOs) in mice triggered peripheral glucose intolerance, a phenomenon further verified in two transgenic mouse models of AD. Systemically injected AβOs failed to induce glucose intolerance, suggesting AβOs target brain regions involved in peripheral metabolic control. Accordingly, we show that AβOs affected hypothalamic neurons in culture, inducing eukaryotic translation initiation factor 2α phosphorylation (eIF2α-P). AβOs further induced eIF2α-P and activated pro-inflammatory IKKβ/NF-κB signaling in the hypothalamus of mice and macaques. AβOs failed to trigger peripheral glucose intolerance in tumor necrosis factor-α (TNF-α) receptor 1 knockout mice. Pharmacological inhibition of brain inflammation and endoplasmic reticulum stress prevented glucose intolerance in mice, indicating that AβOs act via a central route to affect peripheral glucose homeostasis. While the hypothalamus has been largely ignored in the AD field, our findings indicate that AβOs affect this brain region and reveal novel shared molecular mechanisms between hypothalamic dysfunction in metabolic disorders and AD.

Insect herbivores associated with an evergreen tree Goniorrhachis marginata Taub. (Leguminosae: Caesalpinioideae) in a tropical dry forest

Goniorrhachis marginata Taub. (Leguminosae: Caesalpinioideae) is a tree species found in Brazilian tropical dry forests that retain their leaves during the dry season. That being, we addressed the following question: i) How do insect diversity (sap-sucking and chewing), leaf herbivory and defensive traits (tannin and leaf sclerophylly) vary on the evergreen tree species G. marginata between seasons? The abundance of sap-sucking insects was higher in the dry season than in the rainy season. However, we did not verify any difference in the species richness and abundance of chewing insects between seasons. Leaf herbivory was higher in the rainy season, whereas leaf sclerophylly was higher in the dry season. However, herbivory was not related to sclerophylly. Insect herbivores likely decrease their folivory activity during the dry season due to life history patterns or changes in behaviour, possibly entering diapause or inactivity during this period. Therefore, G. marginata acts as a likely keystone species, serving as a moist refuge for the insect fauna during the dry season in tropical dry forest, and the presence of this evergreen species is crucial to conservation strategies of this threatened ecosystem.

The 'Sharpen' filter improves the radiographic detection of vertical root fractures

AIM

To compare the diagnostic accuracy of digital enhancement filters in the diagnosis of vertical root fractures.

METHODOLOGY

The sample consisted of 40 single-rooted teeth randomly divided into two groups: experimental and control. Vertical root fractures were induced in the experimental group using a universal testing machine. All teeth were individually radiographed with three different horizontal angles using the Digora Optime(®) digital system. Three observers separately examined the original and filtered images (3D Emboss, Negative, Sharpen and Shadow). The area under Receiver Operating Characteristic curve values (Az) for each protocol were compared by one-way anova with post hoc Bonferroni test. The significance level was set at 5%.

RESULTS

The highest Az value was obtained using the Sharpen filter, with significant differences from the original and other filtered images (P < 0.05). The 3D Emboss filter had the lowest Az value, which was significantly different from the other filtered images (P < 0.05).

CONCLUSION

When using the Digora Optime(®) system, the 'Sharpen' filter is recommended to improve the radiographic detection of vertical root fractures.

Methodology for porphyrin isolation by high-performance countercurrent chromatography

Countercurrent chromatography is a versatile technique for the isolation of a wide variety of plant substances. However, little attention has been devoted to the application of this technique for the isolation of porphyrins. This class of compounds are of great importance in the medical area and in photocatalysis due to their heterocyclic structure, composed of four modified pyrrol subunits interconnected on their a carbon atoms by methinic bridges. The methanol extract of Gallesia integrifolia was partitioned using different solvents; the dichloromethane fraction was then submitted to countercurrent chromatography. The solvent system composed of n-hexane, ethyl acetate, methanol, and water (1:2.5:2.5:1) was chosen to perform the chromatographic analysis due to the enhanced solubility and the best distribution coefficients of the target compounds. Two porphyrins were isolated by this method and identified as 13(2)-hydroxypheophorbide a methyl ester and pheophorbide a, methyl ester. The solvent system proposed provided good distribution coefficients for both substances (1.27 and 1.87, respectively), and a high resolution factor.

Ants of three adjacent habitats of a transition region between the cerrado and caatinga biomes: the effects of heterogeneity and variation in canopy cover

Habitat heterogeneity and complexity associated with variations in climatic conditions are important factors determining the structure of ant communities in different terrestrial ecosystems. The objective of this study was to describe the horizontal and vertical distribution patterns of the ant community associated with three adjacent habitats in a transition area between the Cerrado and Caatinga biomes at the Pandeiros River, state of Minas Gerais, Brazil. We tested the following hypotheses: (1) the richness and composition of ant species and functional group structure changes between different habitats and strata; (2) habitats with higher tree species richness and density support higher ant species richness; and (3) habitats with lower variation in canopy cover support higher ant species richness. Sampling was conducted in three adjacent habitats and at three vertical strata. Ant species richness was significantly different among vertical strata. Ant species composition was different among both habitats and vertical strata and functional group structure was divergent among habitats. Partitioning of the diversity revealed that the diversity for the three components was statistically different from the one expected by the null model; α and β 2 were higher and β 1 was lower than the values expected by chance. Tree density and variation in canopy cover negatively affected ant species richness. The occurrence of different species and the changing of functional group structures in different habitats and strata suggest an ecological-evolutionary relationship between ants and their habitats and emphasize the need to implement local conservation strategies in the ecotones between biomes.

Evaluation of panoramic radiomorphometric indices related to low bone density in sickle cell disease

SUMMARY

In sickle cell disease, erythroid hyperplasia causes trabecular destruction leading to low bone density. This condition could be suspected by the radiomorphometric indices and your diagnosis becomes relevant in a multidisciplinary context of health care for sickle cell subjects, providing prognostics and contributing to determine adequate therapeutic and preventive actions.

INTRODUCTION

The aim of this study was to assess the risk of low bone density in subjects with sickle cell disease (SCD) through analysis of panoramic radiographic exams by radiomorphometric indices.

METHODS

Seventy-eight Brazilian subjects with SCD took part in this study and were subdivided into four groups: (I) 31 SCD subjects aged under 40 years; (II) 13 SCD subjects aged 40 years or more; (III) 12 normal subjects aged under 40 years; and (IV) 22 normal subjects aged 40 years or more. In the panoramic radiographs, the mandibular cortical index (MCI) classification, increased spacing of the trabecular bone, panoramic mandibular index (PMI), and mental index (MI) were evaluated. Exact Fisher's test was used to compare age between the different groups. Descriptive analysis of the data was performed to evaluate the simple visual estimation of low bone density (increased bone trabecular space and MCI), and a one-way analysis of variance (Bonferroni criteria) was used to compare the means of the quantitative indices (PMI and MI). The significance level was p < 0.05.

RESULTS

In the MCI classification, C2 was more prevalent, especially in groups I and IV. Increased spacing of the trabecular bone was more frequent in groups I and II. MI did not show a statistically significant difference among the groups. PMI showed a statistically significant difference only between groups III and IV.

CONCLUSIONS

The radiomorphometric indices applied in the present study can be used on panoramic radiographs to detect the presence of low bone density in SCD subjects.

Correlation of panoramic radiography and cone beam CT findings in the assessment of the relationship between impacted mandibular third molars and the mandibular canal

OBJECTIVES

The aim of this study was to assess the reliability of four panoramic radiographic findings, both individually and in association, in predicting the absence of corticalization between the mandibular canal and the third molar on cone beam CT (CBCT) images.

METHODS

The sample consisted of 72 individuals (142 mandibular third molars) who underwent pre-operative radiographic evaluation before extraction of impacted mandibular third molars. On panoramic radiographs, the most common signs of corticalization (darkening of roots, diversion of mandibular canal, narrowing of mandibular canal and interruption of white line) and the presence or absence of corticalization between the mandibular third molar and the mandibular canal on CBCT images were evaluated.

RESULTS

Darkening of roots and interruption of white line associated with the absence of corticalization between the mandibular third molar and the mandibular canal on CBCT images were statistically significant, both as isolated findings (p = 0.0001 and p = 0.0006, respectively) and in association (p = 0.002). No statistically significant association was observed for the other panoramic radiographic findings, either individually or in association (p > 0.05).

CONCLUSION

Darkening of roots and interruption of white line observed on panoramic radiographs, both as isolated findings and in association, were effective in determining the risk relationship between the tooth roots and the mandibular canal, requiring three-dimensional evaluation of the case.

Flare-up of hand osteoarthritis caused by zoledronic acid infusion

Zoledronic acid is effective for osteoporosis at a single annual intravenous dose. It usually causes few adverse effects; the most common are related to acute phase reactions. We reported the case of a 64-year-old woman who presented flare-up of hand osteoarthritis after zoledronic acid infusions. Despite the fact that arthralgia is a common side effect of intravenous bisphosphonates, development of inflammatory signs in osteoarthritic joints is a rare event. We hypothesized that this side effect is caused by a release of cytokines secondary to activation of gamma-delta T lymphocytes.

The leukocytes expressing DARPP-32 are reduced in patients with schizophrenia and bipolar disorder

Bipolar disorder (BPD) and schizophrenia (SCZ) are severe disorders representing an enormous social, familiar and individual burden, being SCZ the most disabling psychiatric disorder characterized by psychosis and cognitive impairment. It is well known that SCZ and BPD are associated with abnormalities in dopamine signaling pathway. Recent data in the literature have demonstrated altered expression levels of some proteins involved in the modulation of this pathway in both brain and peripheral tissues. It was shown that protein and mRNA levels of dopamine and cAMP regulated phosphoprotein (DARPP-32) were downregulated in dorsolateral prefrontal cortex (DLPFC) of patients with SCZ or BPD when compared to controls. Due to the difficulty to access brain tissue and the absence of objective laboratory tests for bio-markers, we measured DARPP-32 expression in blood cell sub-populations (CD4+ T lymphocytes, CD56+ NK cells, CD19+ B lymphocytes and CD14+ monocytes) taking advantage of the close relation of nervous and immune systems. Using flow cytometry as the analytical method, our results have shown that the DARPP-32 expression was diminished in CD4+ T lymphocytes, CD19+ B lymphocytes and CD14+ monocytes of BPD patients and was also decreased in CD4+ T lymphocytes and CD56+ NK cells of SCZ patients. These results showed that DARPP-32 expression in immune cells agrees with reports of reduced DARPP-32 protein in the DLPFC of BPD or SCZ patients. Our data suggest that DARPP-32 expression in PBMC could be used as a source of bio-markers to help in the treatment response of neuropsychiatry disorders as a window to the changes in the brain of those patients.

Benign cementoblastoma: case report and review of the literature

Benign cementoblastoma (BC) is a relatively rare odontogenic neoplasm characterized by the formation of a mass of cementum-like tissue connected to the root of a tooth. Clinically, BC has a slow and constant growth pattern, frequently accompanied by pain, and it promotes volume expansion on both the vestibular and lingual surfaces. Radiographically, it appears attached to the apical or lateral portion of the root of a tooth root as a densely radiopaque, well-circumscribed mass surrounded by a thick and uniform radiolucent halo. Treatment usually consists of surgical tooth extraction along with the attached calcified mass or endodontic treatment of the associated tooth, enucleation of the tumor and osseous curettage. In this article, the clinical, radiographic and histopathological features of one case of BC are presented and the variations of the cases cited in the literature are discussed.

Is the 5-HTTLPR polymorphism associated with bipolar disorder or with suicidal behavior of bipolar disorder patients?

The serotonin transporter gene has a 44 bp insertion/deletion polymorphism within the promoter region (5-HTTLPR) with two allelic forms, the long (L) and the short (S) variants. Association between the low-activity S variant and bipolar disorder (BPD) has been shown but its replication has not been consistent. It has also been described as an association between the S allele and suicidal behavior. Since suicidal behavior is a rather frequent event in BPD, an important question is whether suicidality, instead of bipolarity itself, could be related to S allele. We assessed 351 subjects (167 bipolar inpatients and 184 healthy controls). Diagnosis was conducted by a psychiatrist using a structured interview (MINI-PLUS), according to DSM-IV criteria. Suicidal behavior was assessed using a semi-structured instrument and a review of medical records. Genotyping of the 5-HTTLPR was performed using PCR. There were 77 patients with a history of previous suicide attempts. Bipolar patients and healthy controls showed comparable genotypic and allelic frequencies. Patients carrying the S allele made violent suicide attempts more frequently (chi(2) = 20.2; P = 0.0001) and made more suicide attempts (t = 2.6; P = 0.01). We were able to show an association between the S allele and suicidal behavior but not with BPD. Our data suggest that a phenotypic stratification, taking into account the suicidal behavior history, is of pivotal importance when performing association studies between BPD and 5-HTTLPR genotypes, which could explain previous contradictory results.

Cross-cultural adaptation of the Behçet's Disease Current Activity Form (BDCAF) to Brazilian Portuguese language

The Behçet's Disease Current Activity Form (BDCAF) is a clinical instrument used to assess the activity of Behçet's disease (BD), which was originally developed in English. The aim of the present study was to perform a cross-cultural adaptation of the BDCAF to Brazilian Portuguese language and to evaluate its reliability in a population of Brazilian patients with BD. Brazilian Portuguese version of the BDCAF, named BR-BDCAF, was obtained according to established guidelines. Forty Brazilian patients with BD diagnosed according to the International Study Group for Behçet's Disease criteria were assessed by two rheumatologists in independent sessions and submitted to the BR-BDCAF. Inter- and intraobserver agreement were then evaluated by kappa scores (values higher than 0.6 indicated good agreement). Good inter- and intraobserver agreements were achieved for the most common manifestations of BD: kappa scores higher than 0.6 were obtained for oral and genital ulcerations, skin lesions, and articular and general complaints. Moderate interobserver agreement was obtained for ocular activity (kappa 0.483) and fair interobserver agreement was obtained for gastrointestinal (kappa 0.322), major vessel (kappa 0.281), and central nervous system activity (kappa 0.304). BR-BDCAF was found to be a reliable instrument for the classic mucocutaneous and articular manifestations of BD and for general complaints, but complementary assessment is needed to evaluate specific visceral involvement for disease activity.

Sexual differences in reproductive phenology and their consequences for the demography of Baccharis dracunculifolia (Asteraceae), a dioecious tropical shrub

Patterns of phenological variation and reproductive investment were studied in the dioecious shrub Baccharis dracunculifolia DC (Asteraceae), and possible consequences on survivorship were evaluated. The sex ratio was determined in a natural field population (n = 921) of B. dracunculifolia in Belo Horizonte, Brazil. Fifty-two males and 56 females were sampled at random from this population. During the reproductive season of 1999, inflorescence production, shoot growth and mortality, and xylem water potential were recorded for each individual. The population sex ratio was male-biased (1.27 : 1, P < 0.05), and was associated with a higher mortality of female shoots (38.4 vs. 23.1 %, P < 0.05), and individuals (17.8 vs. 11.5 %, P < 0.1), despite lower water stress in female plants. Flowering phenology also differed between the sexes, with males producing more inflorescences, and earlier, than females. Owing to fruit maturation, the number of inflorescences supported by females was higher than that supported by males later in the reproductive season. This occurred during the dry season, and drought stress may have been responsible for the greater female mortality. Thus, the male-biased sex ratio in this population of B. dracunculifolia is probably due to different reproductive functions of males and females. Intersexual differences in reproductive phenology had consequences for plant demography.