Dentine hypersensitivity: a clinical trial to compare 2 strontium densensitizing toothpastes with a conventional fluoride toothpaste

Sixty-nine patients, aged 63-98 years and admitted at the Geneva Geriatric Hospital, were included in the present retrospective study. They received clomipramine orally, 50 or 75 mg/day. Blood concentrations of clomipramine were measured as part of a routine drug monitoring program. Comparison with a reference population of patients aged < or = 65 years indicated that elderly patients with concomitant somatic diseases reach higher dose-normalized concentrations of clomipramine and increased parent drug to demethylated metabolite ratios, as a consequence of impaired demethylation (approximately 50%) and hydroxylation (approximately 25%). Sixty-five percent of patients showed clinical improvement, with a maximum rate of satisfactory response observed in major depression. Severe side effects, such as symptomatic hypotension or confusion, were seen in 20% of patients. Because of 10- and 15-fold interindividual variations in the concentrations of clomipramine and its metabolite, respectively, therapeutic drug monitoring can provide valuable assistance to clinical judgment in individual dose adjustment for patients whose old age, associated somatic diseases, and comedication necessitate additional precautions.     

Simple Robust PID Tuning for Magnetic Levitation Systems Using Model-free Control and $${{\cal H}_\infty}$$ ℋ ∞ Control Strategies

International Journal of Control, Automation and Systems - This paper proposes two control techniques to provide robust tracking for magnetic levitation systems (MLS): model-free control (MFC) and...     

Novel dynamic semiempirical proton exchange membrane fuel cell model incorporating component voltages

This paper introduces a novel dynamic semiempirical model for the proton exchange membrane fuel cell (PEMFC). The proposed model not only considers the stack output voltage but also provides valid waveforms of component voltages, such as the no‐load, activation, ohmic, and concentration voltages of the PEMFC stack system. Experiments under no‐load, ramping load, and dynamic load conditions are performed to obtain various voltage components. According to experimental results, model parameters are optimised using the lightning search algorithm by providing valid theoretical ranges of parameters to the lightning search algorithm code. In addition, the correlation between the vapour and water pressures of the PEMFC is obtained to model the component voltages. Finally, all component voltages and the stack output voltage are validated by using the experimental/theoretical waveforms mentioned in previous research. The proposed model is also compared with a recently developed semiempirical model of PEMFC through particle swarm optimisation. The proposed dynamic model may be used in future in‐depth studies on PEMFC behaviour and in dynamic applications for health monitoring and fault diagnosis.     

The intubating laryngeal mask. II: A preliminary clinical report of a new means of intubating the trachea

To determine the effect of anterior cruciate ligament (ACL) reconstruction on symptoms of pain and instability in patients with chronic ACL insufficiency who had previously undergone meniscectomy, we reviewed a series of 21 symptomatic, previously meniscectomized patients with chronic ACL deficiency (average age, 31 years). Arthroscopically assisted intra-articular ACL reconstruction using a middle, one-third patella-tendon autograft was performed in all cases. All patients had radiographic evidence of degenerative changes before ACL reconstruction. The average time from meniscectomy to ACL reconstruction was 6.6 years. Preoperative and postoperative range of motion, stability, and subjective evaluations were compared. Follow-up averaged 37.4 months (range, 24 to 67 months). Physical examination and postoperative KT-1000 side-to-side measurements revealed three patients (14%) with pathological ligament laxity. One patient had a 2+ Lachman, a 2+ pivot shift, and > 5 mm difference on KT-1000 maximum manual test, and two patients had a 1+ Lachman and a 1+ pivot shift. Range of motion measurements taken at follow-up were not significantly different from preoperative measurements (extension, P = .14; flexion, P = .46). Subjectively, all items on a panel of 15 visual analog scales were improved, but intensity of pain and instability were significantly improved after statistical analysis (P < .05). This review suggests that symptoms of pain and instability in patients with chronic ACL deficiency who have previously undergone meniscectomy can be improved by ACL reconstruction if objective stability is obtained.     

A split-mouth placebo-controlled study to determine the effect of amorphous calcium phosphate in the treatment of dentine hypersensitivity

Many treatments for dentine hypersensitivity are formulated to directly or indirectly occlude the open dentinal tubules associated with the condition. Combining solutions of calcium chloride and potassium phosphate can result in the precipitation of amorphous calcium phosphate. Such a system applied to exposed dentine could occlude dentinal tubules and reduce sensitivity. The aims of this study using a placebo control were to assess the therapeutic value of amorphous calcium phosphate in dentine hypersensitivity and provide further information on the apparently natural improvement in the condition frequently observed in clinical trials. 38 subjects with dentine hypersensitivity affecting 1 tooth in each left and right sides of the jaws were recruited into this split mouth, randomised, double-blind study. At baseline, sensitivity was scored by the subjects on a 0-10 visual apologue scale after tactile, cool and cold water and evaporative stimulation of the test teeth. Active and control, water, solutions were then applied by a 2nd clinician. After 24 h, subjects returned for rescoring. On days 7 and 14, subjects were again rescored and the treatments reapplied. Further follow-up appointments for rescoring were on days 21, 28, 56 and 84. Plaque scores also were recorded from test teeth at each visit. Overall sensitivity decreased considerably and to a similar degree in test and control teeth with no consistent significant treatment difference. Plaque scores also decreased through the study period. It is concluded that either the amorphous calcium phosphate was without therapeutic effect or the activity was masked by the placebo response in the control teeth.     

Guidelines for the design and conduct of clinical trials on dentine hypersensitivity

Clinical trials on dentine hypersensitivity have been numerous and protocols varied. To date there is little consensus as to the conduct of studies on this poorly-understood yet common and painful dental condition. A committee of interested persons from academia and industry was convened to discuss the subject of clinical trials on dentine hypersensitivity and a consensus report is presented. A double-blind randomized parallel groups design is recommended, although cross-over designs may be used for the preliminary screening of agents. Subjects may have multiple sites scored. Sample size will be determined by estimating the variability in the study population, the effect to be detected and the power of the statistical test to be used. Subject selection is based on a clinical diagnosis of dentine hypersensitivity, excluding those with conflicting characteristics such as currently-active medical or dental therapy. The vestibular surfaces of incisors, cuspids and bicuspids are preferred as sites to be tested. A range of sensitivity levels should be included. Tactile, cold and evaporative air stimuli should be applied. Negative and benchmark controls should be incorporated. Most trials should last 8 weeks. Sensitivity may be assessed either in terms of the stimulus intensity required to evoke pain or the subjective evaluation of pain produced by a stimulus using a visual analog or other appropriate scale. The subject's overall assessment may be determined by questionnaire. Outcomes should be expressed in terms of clinically significant changes in symptoms. Follow-up evaluation is required to determine the persistence of changes. At least 2 independent trials should be conducted before a product receives approval.     

COVID-19, Globalization,De-globalization and the Slime Mold's Lessons For Us All

The world is struggling with the COVID-19 pandemic on a backdrop of conflicting globalization and de-globalization forces. A study of biology reveals that nature has been contending with such general issues for billions of years and has come up with broad strategies for their resolution. Copy and paste!     

The intubating laryngeal mask airway: an initial assessment of performance

A new prototype of the laryngeal mask airway (LMA), the intubating laryngeal mask airway (ILMA), was used to facilitate tracheal intubation in 100 fasted patients presenting for elective surgery. Alignment of the ILMA with the larynx was assessed fibreoptically before intubation without the investigator performing the intubation being aware of the view score. Ease of intubation correlated with the view obtained and with the degree of manipulation of the ILMA needed to achieve tracheal intubation. Intubation was successful in 93 patients. Of the seven intubation failures, five occurred in the first 20 patients. Conventional connection to the breathing system and ventilation of the lungs of the patients were possible throughout the intubation procedure.     

Relationship of aging and cytokines to the immunomodulation by delta-9-tetrahydrocannabinol on murine lymphoid cells

The effect of delta 9-tetrahydrocannabinol, the major psychoactive component of marijuana, was investigated utilizing lymphoid cells from 2-week, 2-month, and 18-month-old mice. Previous studies have shown a differential modulation by THC related to age such that cells from adult mice could be up-regulated by THC when stimulated by their CD3 receptor. Cells from 2-week-old and 18-month-old mice were resistant to this THC-mediated enhancement. This paper questioned whether these resistant cells could be up-regulated by either addition or removal of cytokines or by exposure to supernatants derived from adult cells. IL-1, IL-4, and IL-6 modified cell proliferation in general, and their effects had some age-related differences, but these actions were independent of THC. In contrast, the THC-induced enhancement appeared to be related in part to IL-2 levels in the adult cell cultures such that when IL-2 was removed, not only did up-regulation not occur, but THC was, in fact, suppressive. Addition of IL-2 or supernatants from adult cells did lead to a modified THC-induced up-regulation of proliferation in cells from adult or 2-week-old mice. Cells from 18-month-old mice remained resistant to this modulation by THC. This did not represent a general anergy of these older cells since they did proliferate well in culture. These results demonstrate a difference in immune response to THC related to the age of the mice which correlates at least in part to IL-2 levels in 2-week-old and young adult mice. THC modulation, whether immunoenhancing or suppressing, appears to be influenced by the presence of other cell stimulators such as cytokines, and is sensitive to the timing of THC exposure relative to such stimuli.