Economic decision-making is disrupted in individuals with gambling disorder, an addictive behavior observed in Parkinson's disease (PD) patients receiving dopaminergic therapy. The subthalamic ...nucleus (STN) is involved in the inhibition of impulsive behaviors; however, its role in impulse control disorders and addiction is still unclear. Here, we recorded STN local field potentials (LFPs) in PD patients with and without gambling disorder during an economic decision-making task. Reaction times analysis showed that for all patients, the decision whether to risk preceded task onset. We compared then for both groups the STN LFP preceding high- and low-risk economic decisions. We found that risk avoidance in gamblers correlated with larger STN LFP low-frequency (<12-Hz) fluctuations preceding task onset. In particular, the amplitude of low-frequency LFP fluctuations carried significant information about future decisions. Decisions of patients not affected by gambling disorder were instead not correlated with pretask STN LFP. Our results suggest that STN activity preceding task onset affects risk decisions by preemptively inhibiting attraction to high but unlikely rewards in favor of a long-term payoff.
Dentinogenesis imperfecta determines structural alterations of the collagen structure still not completely elucidated. Immunohistochemical analysis was used to assay Type I and VI collagen, various ...non-collagenous proteins distribution in human primary teeth from healthy patients or from patients affected by type I dentinogenesis imperfecta (DGI-I) associated with osteogenesis imperfecta (OI). In sound primary teeth, an organized well-known ordered pattern of the type I collagen fibrils was found, whereas atypical and disorganized fibrillar structures were observed in dentin of DGI-I affected patients. Expression of type I collagen was observed in both normal and affected primary teeth, although normal dentin stained more uniformly than DGI-I affected dentin. Reactivity of type VI collagen was significantly lower in normal teeth than in dentin from DGI-I affected patients (P<0.05). Expressions of dentin matrix protein (DMP)-1 and osteopontin (OPN) were observed in both normal dentin and dentin from DGI-I affected patients, without significant differences, being DMP1 generally more abundantly expressed. Immunolabeling for chondroitin sulfate (CS) and biglycan (BGN) was weaker in dentin from DGI-I-affected patients compared to normal dentin, this decrease being significant only for CS. This study shows ultrastructural alterations in dentin obtained from patients affected by DGI-I, supported by immunocytochemical assays of different collagenous and non-collagenous proteins.
Closure of the sigmoid-jugular complex is generally planned during various surgical procedures on the skull base, either to repair a jugular foramen lesion or as the oncological boundary of the ...resection. A series of 218 cases of skull base tumour surgeries was analysed in which closure of the sigmoid-jugular complex was systematically planned (bilaterally in one case) in patients treated for jugular foramen paragangliomas, squamous cell carcinomas and other temporal bone tumours. Surgery was performed via a petro-occipital trans-sigmoid approach in 61 cases, an infratemporal A in 128, en bloc subtotal temporal bone resections in 10 and other approaches in 20. In our experience, planned unilateral (and, in one case, bilateral) closure of the sigmoid-jugular complex had no clinical consequences. The vicarious drainage of the skull base was always assessed preoperatively, revealing no contraindications to intraoperative sinus closure. Given the scarcity of literature on this subject, the present report shows that the procedure is associated with low morbidity and helps to improve our understanding of cerebral venous discharge.
The cordierite is commonly prepared by reaction of talc, clay and gibbsite within the range of 1200–1350
°C. This study deals with the effect of the amorphization by grinding of that mixture and its ...influence on the cordierite formation.
The mixture previously mentioned underwent six different treatments: mixing without grinding (A) (only mixing); non-amorphizing grinding (A
M) and amorphizing grinding in oscillating mill at four different times (H samples). The phases formed by thermal treatment were studied using differential thermal analysis (DTA)–thermogravimetric analysis (TG)–DTG, dilatometries and X-ray diffraction (XRD) techniques in certain combinations.
The thermal analysis of the A and A
M series were compared and they do not show significant differences, whereas the H samples present remarkable alterations in the DTA peaks as well as in the weight losses (TG). Thus, a great number of DTA peaks tend to decrease the temperature of the maximum and to lower the intensity as the amorphization time increases.
Calcination tests performed within the range 900–1200
°C show important differences in the diffractograms obtained from the intermediate products. While at 1350
°C the A and H samples reach the same final phases, within the range 1200–1360
°C they present important differences in the DTA indicating that the sequence and direction of reaction are different. The same behavior can be observed by dilatometric analysis.
Dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein (DSPP) are extracellular matrix proteins produced by odontoblasts involved in the dentin mineralization. The aim this study was to ...compare the distribution of DMP1 and DSPP in human sound dentin vs human sclerotic dentin. Sixteen sound and sixteen carious human molars were selected, fixed in paraformaldehyde and processed for immunohistochemical detection of DMP1 and DSPP by means of light microscopy, transmission electron microscopy (TEM) and high-resolution field emission in-lens scanning electron microscopy (FEI-SEM). Specimens were submitted to a pre-embedding or a post-embedding immunolabeling technique using primary antibodies anti DMP1 and anti-DSPP and gold-conjugated secondary antibodies. Other samples were processed for the detection of DMP1 and DSPP levels. Dentin from these samples was mechanically fractured to powder, then a protein extraction and a protein level detection assay were performed. DMP1 and DSPP were more abundant in carious than in sound samples. Immunohistochemical analyses in sclerotic dentin disclosed a high expression of DMP1 and DSPP inside the tubules, suggesting an active biomineralization of dentin by odontoblasts. Furthermore, the detection of small amounts of these proteins inside the tubules far from the carious lesion, as shown in the present study, is consistent with the hypothesis of a preventive defense of all dentin after a noxious stimulus has undermined the tooth.
Magnesium aluminate spinel (MgAl2O4) is a mixed oxide with a cubic structure and it is considered as an excellent raw material for ceramics due to its chemical and physical properties. Most studies ...on formation and sintering of spinel were carried out under air atmosphere. In this work, spinel formation and sintering are studied using reducing atmospheres. Stoichiometric, alumina- and magnesia-rich spinels were prepared from calcined alumina and brucite. The spinel synthesis was studied up to 1300°C using XRD and dilatometric techniques. Sintering was carried out on isostatically pressed pellets up to 1650°C using: air (PO2=0.21), CO/CO2 mixture (PO2∼10−10) and pure CO gas (PO2∼10−15). Spinel formation was slightly affected by the particle size of precursors, but not by the atmosphere. The alumina-rich spinel shows the higher stability during sintering. A weight loss due to magnesium volatilization was verified in magnesia-rich spinel under CO atmosphere. The lattice parameters measured were in accordance with the weight losses and densities observed. Microstructures show microporosities due to magnesium loss.
Objective
To analyse life‐threatening obstetric complications that occurred in public hospitals in Argentina.
Design
Multicentre collaborative cross‐sectional study.
Setting
Twenty‐five hospitals ...included in the Perinatal Network of Buenos Aires Metropolitan Area.
Population
Women giving birth in participating hospitals during a 1‐year period.
Methods
All cases of severe maternal morbidity (SMM) and maternal mortality (MM) during pregnancy (including miscarriage and induced abortion), labour and puerperium were included. Data were collected prospectively.
Main outcome measures
Identification criteria, main causes and incidence of SMM; case‐fatality rates, morbidity–mortality index and effective intervention's use rate.
Results
A total of 552 women with life‐threatening conditions were identified: 518 with SMM, 34 with MM. Identification criteria for SMM were case‐management (48.9%), organ dysfunction (15.2%) and mixed criteria (35.9%). Incidence of SMM was 0.8% (95% confidence interval 95% CI 0.73–0.87%) and hospital maternal death ratio was 52.3 per 100 000 live births (95% CI 35.5–69.1). Main causes of MM were abortion complications and puerperal sepsis; main causes of SMM were postpartum haemorrhage and hypertension. Overall case‐fatality rate was 6.2% (95% CI 4.4–8.6): the highest due to sepsis (14.8%) and abortion complications (13.3%). Morbidity‐mortality index was 15:1 (95% CI 7.5–30.8). Use rate of known effective interventions to prevent or treat main causes of MM and SMM was 52.3% (95% CI 46.9–57.7).
Conclusions
This study describes the importance of life‐threatening obstetric complications that took place in public hospitals with comprehensive obstetric care and the low utilisation of known effective interventions that may decrease rates of SMM and MM. It also provides arguments that justify the need to develop a surveillance system for SMM.
Three experiments investigated the malleability of perceived
plausibility and the subjective likelihood of occurrence of plausible and
implausible events among participants who had no recollection of ...experiencing
them. In Experiment 1, a plausibility-enhancing
manipulation (reading accounts of the occurrence of events) combined
with a personalized suggestion increased the perceived plausibility of the
implausible event, as well as participants' ratings of the
likelihood that they had experienced it. Plausibility and likelihood
ratings were uncorrelated. Subsequent studies showed that the
plausibility manipulation alone was sufficient to increase likelihood ratings
but only if the accounts that participants read were set in a contemporary
context. These data suggest that false autobiographical beliefs can be
induced in clinical and forensic contexts even for initially implausible
events.
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