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11.
Horizontal root fractures (HRF) usually affect anterior teeth of male patients as a result of trauma. The consequences can be complex because of combined damage to different tissues, but it has been reported that root fractures undergo healing in majority cases. Diagnosis of HRF must be based on clinical findings, sensibility tests, and radiographic examination. The cone‐beam computed tomography (CBCT) has already been proven to be superior among other radiographic modalities for diagnostic imaging of root fractures. However, CBCT in these cases needs to be used in a careful manner, and only when the radiation exposure should be justified by the potential diagnostic benefits and improvement of the treatment results. This case report describes a case of spontaneously healed horizontal root fracture with displacement of the fragments and discusses the usefulness of CBCT in the follow‐up of root fractures cases.  相似文献   
12.

Background

There is an increased prevalence of asthmatic, obese patients undergoing bariatric surgery. The objective of our study is to evaluate the severity, level of control, respiratory medication use, and time required for prebariatric surgery asthma control.

Methods

This is a prospective study in which 88 obese asthmatics were evaluated by a pulmonologist in two steps, prebariatric surgery. In the first step, patients were evaluated for severity, level of control, and respiratory medication in use, categorized as bronchodilators and corticosteroids. In the second step, the time required for asthma control between steps and appropriate respiratory medication was determined.

Results

Thirty-eight obese patients (43.2%) had intermittent asthma, 22 had mildly persistent (25.0%), 24 moderately persistent (27.3%), and 4 severely persistent (4.5%). There were 43 patients with controlled asthma (48.9%), 31 partly controlled (35.2%), and 14 uncontrolled (15.9%). The study sample showed a significant increase in bronchodilators in the first step and corticosteroids in the second step (p?≤?0.0001). Comparisons between steps showed significant differences with a reduction of bronchodilators and increase in corticosteroids in the second step (p?≤?0.0001). The mean time (days) required for asthma control between steps was 28.98?±?33.40 days, with significant differences between groups (p?≤?0.001).

Conclusions

In prebariatric surgery, there was a higher proportion of intermittent asthma and uncontrolled asthma, with asthma severity influencing the achievement of asthma control and the time required for surgical release.  相似文献   
13.

Background

l-glutamate is a major excitatory neurotransmitter in the mammalian brain. Glutamate receptors have been reported in the rat adrenal cortex and in human aldosterone-producing adenomas (APA). However, details regarding the expression levels and functions of these receptors in human adrenocortical tissues remain unknown.

Methods

The mRNA levels of glutamate receptors were evaluated by qPCR in: 12 normal adrenal cortex (NAC), 11 APA, and 12 cortisol-producing adenoma (CPA) tissues. Protein localization was evaluated by immunohistochemistry for 15 NAC, 5 idiopathic hyperaldosteronism cases, 15 APA and 15 CPA. H295R cells were treated with angiotensin-II or forskolin alone or combined with the GRM2/3 agonist LY354740.

Results

The level of GRM3 mRNA was higher in APA than in CPA (P = 0.0086) or NAC (P = 0.0022). GRM1, IGLUR2, and IGLUR3 were also detected in adrenocortical tissues. When added to angiotensin-II/forskolin treatments, LY354740 decreased aldosterone and cortisol production in H295R cells.

Conclusions

GRM3 is considered to regulate steroidogenesis in adrenocortical tissues.  相似文献   
14.
Herein, a combination of heteropolyacids and ionic liquids as a catalytic system was studied for the Biginelli multicomponent reaction; the positive ionic liquid effect associated with the acidic strength of zeolite-supported heteropolyacids made this combination an efficient catalytic system for the multicomponent synthesis of 3,4-dihydropyrimidin-2(1H)-one/thione derivatives. The acidic strength effect was evaluated, and a range was determined in which the reaction provided better results. The mechanism of the reaction was also investigated in the presence and absence of ionic liquids, and two features of paramount importance were revealed: the mechanism could be tuned to proceed through only one reaction path among three possibilities and the kinetics of the reaction was significantly faster in the presence of an ionic liquid.

Heteropolyacids and ionic liquid effect allowed tuning of the Biginelli reaction mechanism and synthesis of 3,4-dihydropyrimidin-2(1H)-one/thione derivatives in an efficient, recyclable fashion. The role of acidic strength and supported heteropolyacid is disclosed.  相似文献   
15.

Background

Neurotrophic factors have been investigated in the pathophysiology of alcohol and drug dependence and have been related to early life stress driving developmental programming of neuroendocrine systems.

Methods

We conducted a follow-up study that aimed to assess the plasma levels of glial cell line–derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT3) and neurotrophin-4/5 (NT4/5) in crack users during 3 weeks of early abstinence in comparison with healthy controls. We performed a comprehensive clinical assessment in female inpatients with crack cocaine dependence (separated into 2 groups: participants with (CSA+) and without (CSA−) a history of childhood sexual abuse) and a group of nonuser control participants.

Results

Our sample included 104 women with crack cocaine dependence and 22 controls; of the women who used crack cocaine, 22 had a history of childhood sexual abuse and 82 did not. The GDNF plasma levels in the CSA+ group increased dramatically during 3 weeks of detoxification. In contrast, those in the CSA− group showed lower and stable levels of GDNF under the same conditions. Compared with the control group, BDNF plasma levels remained elevated and NGF levels were reduced during early abstinence. We found no differences in NT3 and NT4/5 between the patients and controls. However, within-group analyses showed that the CSA+ group exhibited higher levels of NT4/5 than the CSA− group at the end of detoxification.

Limitations

Some of the participants were using neuroleptics, mood stabilizers or antidepressants; our sample included only women; memory bias could not be controlled; and we did not investigate the possible confounding effects of other forms of stress during childhood.

Conclusion

This study supports the association between early life stress and peripheral neurotrophic factor levels in crack cocaine users. During early abstinence, plasmastic GDNF and NT4/5 were the only factors to show changes associated with a history of childhood sexual abuse.  相似文献   
16.
Background To evaluate the efficacy of intra-alveolar administration of dexamethasone 4 mg in the control of edema, trismus, and pain resulting from the extraction of impacted lower third molars and the drug permeability through the oral mucosa by in silico prediction.Material and Methods The randomized, double-blind, split-mouth clinical trial included patients who had both impacted lower third molars in equivalent positions. Hemiarches were divided into control side when dexamethasone was administered orally and experimental side when dexamethasone was administered using the intra-alveolar route. Patients were evaluated considering edema, trismus, and pain. The permeability of dexamethasone through the oral mucosa was assessed by in silico prediction. Student’s t-test was selected for comparative analysis of edema and trismus, and the chi-square test analyzed the distribution of postoperative pain between the sides.Results There were no significant differences between the routes of administration in measuring symptoms between the pre and postoperative times (p>0.05). In silico prediction suggested that dexamethasone molecular characteristics facilitate intra-alveolar administration.Conclusions Intra-alveolar administration had similar efficacy to oral administration in controlling symptoms of post-surgical inflammation of impacted lower third molars. Key words:Molar, third, tooth, impacted, oral surgical procedures, dexamethasone.  相似文献   
17.
Paired maternal and newborn urine and amniotic fluid from 138 subjects collected during a Zika virus (ZIKV) outbreak was analyzed for ZIKV by gene amplification (RT-qPCR), and the findings were correlated with clinical symptoms and neurological anomalies in the babies. ZIKV was detected in 1 of 9 symptomatic women (11.1%) and in 19 of 129 asymptomatic women (14.7%). Neurological manifestations were present in 19 babies (13.7%), 10 of 20 (50%) positive and 9 of 119 (7.6%) negative (p < 0.001) for ZIKV. Twelve (8.6%) urines collected during gestation were ZIKV-positive; only 2 remained positive for ZIKV postpartum. Six (4.1%) newborn urines collected within 1 day of delivery were ZIKV-positive cases. In 3 of these cases, ZIKV was detected in mother’s urine pre- and postpartum and in both mother’s urine and babies’ urine. Four of the amniotic fluid samples (2.9%) were ZIKV-positive. Among ZIKV-negative babies with neurological sequel, 87.5% were female; in contrast, 72.7% ZIKV-positive babies with neurological abnormalities were male (p = 0.019). We conclude that during a ZIKV outbreak, clinical symptoms and ZIKV detection in biological fluids are poor predictors of infection and adverse neurologic sequel in newborns.  相似文献   
18.
19.
Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) are decreased and mean arterial pressure (MAP) is increased after unilateral release of bilateral ureteral obstruction (BUO). An imbalance between vasoconstrictor and vasodilator substances may explain the hemodynamic alterations seen in this setting. The present study examines the role of endothelin-1 in such alterations. Rats with BUO (N = 10) had significantly lower GFR and ERPF (ml/min/kg body wt) than sham-operated rats (SOR, N = 9) (1.40 +/- 0.14 vs. 6.20 +/- 0.38 and 5.12 +/- 0.68 vs. 20.2 +/- 2.20, respectively) and significantly higher MAP (mm Hg) than SOR (154.9 +/- 3.2 vs. 120.6 +/- 1.7). Rats with BUO given a specific antiendothelin antibody (N = 8) had significantly higher GFR (2.10 +/- 0.12) and ERPF (7.46 +/- 0.95) than BUO control rats, but there were no significant changes in MAP (159.5 +/- 5.8). In SOR (N = 6), mechanical denudation of the main renal artery endothelium did not significantly affect renal function when compared to renal function in control SOR. However, the same maneuver significantly lowered GFR (0.64 +/- 0.17) and ERPF (1.67 +/- 0.36) in BUO rats (N = 5) when compared to BUO control rats. We conclude that: (1) endothelin-1 has a significant vasoconstrictor role in rats with BUO of 24 hours duration and accounts for a portion of the decrease in glomerular filtration rate seen in rats after unilateral release of bilateral ureteral obstruction, and (2) in the BUO setting, the net role of the renal artery endothelium is vasodilatory.  相似文献   
20.
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