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1.
Phys Rev E ; 108(2-1): 024314, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37723784

ABSTRACT

In this work, we model an individual social career by a finite-size trajectory along a hexagonal lattice moving only forward. At each bifurcation, the individual makes a free-will choice to follow one or the other branch within an uncertain outcome. Considering that those choices are determined by an individual self built from endogenous characteristics, we assume they are random following a binomial distribution. As a result, the individual ascends or descends on the social scale via random progress through the series of bifurcations made at the encountered junctions. The related stochastic process is found to be diffusive. For different selves coming from different points on the social scale, progress does overlap. In addition, we include the possibility of continuous transition across the lattice caused external influences as an epiphany. The occurrence of a quantum leap resulting from an affirmative action opportunity is also included. We also treat the case of a social group being acted by a collective epiphany as with education. The results highlight the key effect of epiphanies and quantum leaps to promote upward mobility across social classes.

2.
Eur J Endocrinol ; 181(5): 509-517, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31484162

ABSTRACT

INTRODUCTION: The role of vitamin D on bone microarchitecture and fragility is not clear. OBJECTIVE: To investigate whether vitamin D deficiency (25(OH)D <20 ng/mL) increases cortical bone loss and the severity of fractures. DESIGN: Cross-sectional study of 287 elderly women with at least one prevalent low-impact fracture. METHODS: Biochemistry, X-rays to identify vertebral fractures (VFs) and to confirm non-vertebral fractures (NonVFs), and high-resolution peripheral quantitative computed tomography (HR-pQCT) to evaluate bone microstructure. RESULTS: Serum 25(OH)D levels were associated with body mass index (BMI: r = -0.161, P = 0.006), PTH (r = -0.165; P = 0.005), CTX (r = -0.119; P = 0.043) and vBMD at cortical bone (Dcomp: r = 0.132; P = 0.033) and entire bone (D100: r = 0.162 P = 0.009) at the distal radius, but not at the tibia. Age and PTH levels were potential confounding variables, but in the multiple linear regressions only BMI (95% CI: 0.11-4.16; P < 0.01), 25(OH)D (95% CI: -0.007 to 1.70; P = 0.05) and CTX (95% CI: -149.04 to 21.80; P < 0.01) predicted Dcomp, while BMI (95% CI: 1.13-4.18; P < 0.01) and 25(OH)D (95% CI: 0.24-1.52; P < 0.01) predicted D100. NonVFs predominated in patients with 25(OH)D <20 ng/mL (P = 0.013). Logistic regression analysis showed a decrease in the likelihood of presenting grade 2-3 VFs/NonVFs for every increase in 25(OH)D (OR = 0.962, 95% CI: 0.940-0.984; P = 0.001), BMI (OR = 0.932, 95% CI: 0.885-0.981; P = 0.007) and D100 at radius (OR = 0.994, 95% CI: 0.990-0.998; P = 0.005). CONCLUSION: In elderly patients with prevalent fractures, vitamin D deficiency was associated with cortical bone loss and severity of fractures.


Subject(s)
Fractures, Bone/epidemiology , Fractures, Bone/etiology , Osteoporosis/epidemiology , Osteoporosis/etiology , Vitamin D Deficiency/complications , Age Factors , Aged , Aged, 80 and over , Body Mass Index , Cross-Sectional Studies , Female , Humans , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/etiology , Parathyroid Hormone/blood , Spinal Fractures/epidemiology , Spinal Fractures/etiology
3.
Int Endod J ; 50(4): 407-414, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27000665

ABSTRACT

AIM: To evaluate, using a novel micro-CT approach, the solubility and dimensional changes of an MTA-based sealer inside the root canal system after a solubility challenge. The MTA-based material (MTA Fillapex) was compared to a gold standard epoxy-based endodontic sealer (AH Plus). METHODOLOGY: Ten human mandibular premolars with a single canal were divided randomly into two groups (n = 5) according to the sealer used. The canals were instrumented using the Reciproc System (VDW) with a R40 file and filled with R40 gutta-percha cones and one of the sealers. The filled canals were immediately scanned in a micro-CT, and after that, the teeth were immersed in 20 mL phosphate-buffered saline (PBS) at 37 °C for 7 days, when they were removed and rescanned. Final image stacks were registered against the initial stacks and the numerical difference between the initial and final volume of the filling material was obtained. Calculations were performed to identify dimensional changes of the filling material. All image stacks were 3D rendered to disclose areas of dislocation of the filling material inside or outside the root canal. The Shapiro-Wilk's test revealed that data were normally distributed; thus, the Student's t-test was used to detect statistically significant changes, assuming a 5% α-error. RESULTS: No significant changes were seen for the percentage volume of material lost after the solubility challenge for both AH Plus and MTA Fillapex groups (1.44% and 1.16%, respectively). A significant difference was, however, found for the volume of filling material which revealed dimensional changes after the solubility test (6.68% for MTA Fillapex and 1.09% for AH Plus). In fact, observation of 3D models disclosed that MTA Fillapex was associated with material extrusion through the foramen in all but one sample. In AH Plus filled samples, no material extrusion was detected. CONCLUSIONS: Although the solubility of both sealers was similar using this novel micro-CT approach, MTA Fillapex was associated with significant dimensional changes related to material extrusion through the apex after PBS storage compared to AH Plus.


Subject(s)
Aluminum Compounds/therapeutic use , Calcium Compounds/therapeutic use , Epoxy Resins/therapeutic use , Oxides/therapeutic use , Root Canal Filling Materials/therapeutic use , Root Canal Obturation/methods , Silicates/therapeutic use , X-Ray Microtomography/methods , Aluminum Compounds/chemistry , Calcium Compounds/chemistry , Dental Pulp Cavity/diagnostic imaging , Drug Combinations , Epoxy Resins/chemistry , Humans , Oxides/chemistry , Root Canal Filling Materials/chemistry , Silicates/chemistry , Solubility
4.
Horm Metab Res ; 46(4): 259-68, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24627101

ABSTRACT

Childhood obesity is growing in prevalence. Obesity and bone dysfunctions may be related disorders, and therefore our aim was to study the impact of the early overfeeding (EO) in offspring bone health since weaning up to adulthood. To induce EO during lactation, litter size was adjusted to 3 male rats per litter (SL). Litter containing 10 pups per mother was the control (NL). Bone tissue was evaluated by dual-energy X-ray absorptiometry, computed tomography, microcomputed tomography, biomechanical tests, and serum analyses. SL offspring presented higher body weight, fat mass, lean mass from 21 up to 180 days, hyperphagia, and higher visceral fat mass. Bone analysis showed that SL offspring presented higher total bone mineral density (BMD) only at 180 days, and higher total bone mineral content and higher bone area from 21 until 180 days. At 180 days, SL offspring presented higher femur BMD and fourth lumbar vertebra (LV4) BMD, higher femoral head radiodensity and LV4 vertebral body radiodensity, lower trabecular pattern factor and trabecular separation, however with higher trabecular number, higher maximal load, resilience, stiffness and break load, and lower break deformation. SL group had, at 180 days, higher osteocalcin and lower C-terminal cross-linked telopeptide of type I collagen (CTX I). We have shown that the excess of fat mass contributed to an increased bone mass, and hypothesized that this increase could be mediated by the hypothyroidism and previous higher thyroid hormone action and hyperleptinemia at weaning. Furthermore, the increased biomechanical loading due to increased body weight probably help us to understand the protective effects obesity exerts upon bone health.


Subject(s)
Feeding Behavior , Femur/pathology , Femur/physiopathology , Overnutrition/pathology , Overnutrition/physiopathology , Absorptiometry, Photon , Animals , Animals, Newborn , Biomechanical Phenomena , Body Weight , Bone Density , Collagen Type I/metabolism , Female , Femur/diagnostic imaging , Intra-Abdominal Fat/physiopathology , Male , Organ Size , Osteocalcin/metabolism , Overnutrition/diagnostic imaging , Peptides/metabolism , Rats, Wistar , Weaning , Weight-Bearing , X-Ray Microtomography
5.
Anal Chim Acta ; 778: 9-14, 2013 May 17.
Article in English | MEDLINE | ID: mdl-23639393

ABSTRACT

In the present study a method for the simultaneous determination of aflatoxins B2 and G2 in peanuts has been developed. The method uses second order standard addition method and excitation-emission fluorescence data together with parallel factor analysis (PARAFAC). The aflatoxin analysis was based on extraction with methanol-water and carried out using immunoaffinity clean-up. The results of PARAFAC on a set of spiked and naturally contaminated peanuts indicated that the two aflatoxins could be successfully determined. The method was validated and analytical figures of merit were obtained for both analytes. The limits of detection (LOD) were 0.05 and 0.04 µg kg(-1) for aflatoxins B2 and G2, respectively. The limits of quantification (LOQ) were 0.16 and 0.12 µg kg(-1) for aflatoxins B2 and G2, respectively. Coupling of spectrofluorimetry with PARAFAC can be considered as an alternative method for quantification of aflatoxins in the presence of unknown interferences obtained through analysis of highly complex matrix of peanuts samples at a reduced cost per analysis.


Subject(s)
Aflatoxins/analysis , Arachis/chemistry , Food Microbiology/methods , Limit of Detection , Principal Component Analysis
6.
Arq. bras. med. vet. zootec ; 65(1): 6-12, fev. 2013. tab
Article in English | LILACS | ID: lil-667529

ABSTRACT

The present study aimed to verify the caprine semen characteristics during dry and rainy seasons in the Brazilian Northeast, and the influence of these seasons on cooled semen. Seminal volume, concentration, percentage of motile cells, vigor and spermatic morphology, as well as biochemical profile (fructose, citric acid, P, Ca2+, Mg, total proteins and phospholipase A2 activity) were analyzed. It was observed a reduction (P<0.05) in normal sperm morphology, fructose, citric acid, P, Mg and total protein concentration during the dry season, which did not affect the motility, vigor, volume and sperm concentration. Phospholipase A2 activity was increased during the dry season (P<0.05). The analysis of the semen cooled at 4ºC during 48 hours showed reduction in total motility and vigor sperm during the dry season (P<0.05). Based on these results, we conclude that the best period of year for caprine semen cooling is the rainy season.


Verificou-se as características seminais de caprinos durante a época seca e a chuvosa no Nordeste brasileiro e a influência da época no resfriamento do sêmen. Foram mensurados volume, concentração espermática, porcentagem de espermatozoides móveis, vigor, morfologia espermática e características bioquímicas (frutose, ácido cítrico, fósforo, magnésio, proteínas totais e atividade da fosfolipase A2). Observou-se redução (P<0,05) no número de espermatozóides morfologicamente normais, frutose, ácido cítrico, fósforo, magnésio e proteínas totais durante a época seca que não influenciaram na motilidade, vigor, volume e concentração do sêmen. Entretanto, a atividade da fosfolipase A2 foi maior na época seca. Quando o sêmen foi submetido ao resfriamento a 4ºC durante 48 horas, houve redução (P<0,05) na motilidade total e no vigor espermático durante a época seca. Com base nesses resultados, conclui-se que o período chuvoso é melhor para resfriar sêmen de caprinos no Nordeste brasileiro.


Subject(s)
Animals , Male , Semen Preservation/statistics & numerical data , Semen Preservation/veterinary , Semen/chemistry
7.
Anesthesiology ; 90(6): 1528-33, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10360847

ABSTRACT

BACKGROUND: Guidelines for cancer pain management include nonsteroidal antiinflammatory drugs with opioids administered in a time-contingent manner. This study was designed to evaluate the role of oral ketamine or transdermal nitroglycerin polymer, a nitric oxide donor, as coadjuvants to oral morphine in cancer pain therapy. METHODS: After institutional approval and informed patient consent were obtained, 60 patients with cancer pain were randomized to one of four groups (n = 15) and studied prospectively to evaluate analgesia and any adverse effects. A visual analog scale that consisted of a 10-cm line with 0 representing "no pain at all" and 10 representing "the worst possible pain" was introduced. All patients were regularly taking oral amitriptyline 50 mg at bedtime. The morphine regimen was adjusted individually to a maximal oral dose of 80-90 mg/day to keep the visual analog scale score less than 4. When patients reported pain (visual analog scale of 4 or more), despite taking 80-90 mg oral morphine daily, the test drug was added as follows: the control group (CG) received an additional 20 mg oral morphine (10 mg at 12-h intervals); the nitroglycerin group (NG) received a 5-mg nitroglycerin patch daily; the ketamine group (KG) received 0.5 mg/kg oral ketamine at 12-h intervals; and the dipyrone group (DG) received 500 mg oral dipyrone at 6-h intervals. Patients were free to manipulate their daily morphine consumption when the test drug was introduced to keep their visual analog scale score less than 4. RESULTS: The groups were similar with respect to demographic data and visual analog scale pain scores before treatment. The visual analog scale scores after the test drug was introduced were similar among the groups. The daily consumption of oral morphine was as follows: on day 15: CG = DG = NG (P > 0.05), CG > KG (P = 0.036); on day 20: CG > NG = KG (P < 0.02) (CG > KG, P < 0.005; CG > NG, P < 0.02), DG > KG (P < 0.05); on day 30: CG = DG > KG = NG (P < 0.05). Patients in the CG and DG groups reported somnolence, but patients in the NG and KG groups did not. CONCLUSIONS: Low-dose ketamine and transdermal nitroglycerin were effective coadjuvant analgesics. In conjunction with their opioid tolerance-sparing function, joint delivery of ketamine or nitric oxide donors with opiates may be of significant benefit in cancer pain management.


Subject(s)
Analgesics, Opioid/administration & dosage , Ketamine/administration & dosage , Morphine/administration & dosage , Neoplasms/physiopathology , Nitric Oxide Donors/administration & dosage , Nitroglycerin/administration & dosage , Pain, Intractable/drug therapy , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Administration, Cutaneous , Administration, Oral , Adult , Aged , Female , Humans , Ketamine/adverse effects , Male , Middle Aged , Morphine/adverse effects , Nitric Oxide/physiology , Nitroglycerin/adverse effects , Prospective Studies
8.
Reg Anesth ; 22(3): 243-8, 1997.
Article in English | MEDLINE | ID: mdl-9168216

ABSTRACT

BACKGROUND AND OBJECTIVES: This study was conducted to evaluate the analgesic efficacy of tramadol, an analgesic with both opioid and nonopioid actions (norepinephrine and serotonin pathways), with beta-cyclodextrin piroxicam, a nonsteroidal antiinflammatory drug, in the perioperative setting. METHODS: The study population consisted of 48 patients scheduled for minor abdominal procedures, who were assigned to one of four groups of 12 patients each. The premedication was either a placebo tablet or a 192.1-mg beta-cyclodextrin piroxicam tablet, administered orally 30-40 minutes before anesthesia induction. After intravenous administration of tramadol 1.5 mg/kg, anesthesia was induced with an intravenous loading dose of propofol. Anesthesia was maintained an intravenous infusion of propofol at 6-12 mg/kg/h plus either saline or tramadol at 1.2 mg/kg/h, atracurium, and a 2:1 nitrous oxide-oxygen mixture. The control group received a placebo tablet and an infusion of saline with propofol for anesthesia maintenance; the tramadol group received a placebo tablet and a continuous tramadol-propofol infusion; the beta-cyclodextrin piroxicam (BCP) group received a BCP tablet and a continuous saline-propofol infusion; and the beta-cyclodextrin piroxicam-tramadol (BCPT) group received beta-cyclodextrin piroxicam and a continuous tramadol-propofol infusion. RESULTS: The relative propofol consumption by the four groups was control = BCP (P > .05) >tramadol (P < .001) > B-CPT (P < .0002). The time for analgesic rescue decreased in the order BCPT > BCP (P < .0002) = tramadol > control (P < .001). The degree of sedation and the visual analog scores 10-cm scale at the time patients requested rescue analgesics were similar among the groups (P > .05). CONCLUSIONS: The combination of tramadol and beta-cyclodextrin piroxicam provided better perioperative analgesia than tramadol alone.


Subject(s)
Analgesics, Non-Narcotic/therapeutic use , Analgesics, Opioid/therapeutic use , Pain, Postoperative/drug therapy , Pain/drug therapy , Piroxicam/therapeutic use , Tramadol/therapeutic use , beta-Cyclodextrins , Abdomen/surgery , Adult , Analgesics, Non-Narcotic/administration & dosage , Analgesics, Opioid/administration & dosage , Cyclodextrins , Double-Blind Method , Drug Combinations , Excipients , Female , Humans , Injections, Intravenous , Intraoperative Period , Male , Middle Aged , Pain Measurement , Piroxicam/administration & dosage , Prospective Studies , Tramadol/administration & dosage
9.
Anesth Analg ; 82(3): 617-20, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8623971

ABSTRACT

This study was designed to qualitatively evaluate the analgesic actions of intrathecal neostigmine alone and with intravenous (IV) N-butyl-scopolamine on somatic and visceral pain. Twenty-seven patients scheduled for both tubal ligation and vaginoplasty were divided into three groups. Patients received a standard anesthetic with thiopental, atracurium, and N2O/O2/enflurane. N-butyl-scopolamine, 20 mg, or saline was administered as a 2-mL IV bolus 20 min before the end of the surgical procedure. The control group (CG) received spinal and IV saline; the neostigmine group (NG), spinal neostigmine and IV saline; and the neostigmine-N-butyl-scopolamine group (NSG), spinal neostigmine and IV N-butyl-scopolamine. Postoperatively, patients assessed their pain on a 10-cm visual analog scale (VAS). The CG had both visceral and somatic pain at the first 30-min assessment, and all patients requested morphine. Patients from the NG had only visceral pain from the first assessment; however, they had lower VAS scores (P = 0.026) and requested less morphine (P = 0.037). Patients from the NSG were pain free during all assessment times (P < 0.0001). Neostigmine was more effective for somatic pain than visceral pain. N-butyl-scopolamine administration acted peripherally as an effective complement for treatment of visceral pain, reflecting an association between central cholinergic effects and peripheral anticholinergic effects in the treatment of visceral postoperative pain.


Subject(s)
Analgesia , Butylscopolammonium Bromide/administration & dosage , Cholinergic Antagonists/administration & dosage , Neostigmine/administration & dosage , Pain, Postoperative/prevention & control , Parasympatholytics/administration & dosage , Parasympathomimetics/administration & dosage , Adult , Analgesics/administration & dosage , Double-Blind Method , Female , Humans , Injections, Intravenous , Injections, Spinal , Morphine/administration & dosage , Pain Measurement , Prospective Studies , Sterilization, Tubal , Vagina/surgery , Viscera
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