Detection of the unknown components of the oral microflora of teeth with periapical radiolucencies in a Turkish population using next-generation sequencing techniques.

AIM: To detect the unknown components of the oral microbiome and the effects of root canal treatment in a Turkish population and to evaluate the changes in microbial diversity in the root canals before and after treatment. METHODOLOGY: Single-rooted central and lateral maxillary incisors with one canal were chosen from 20 patients. Baseline samples of intact intracanal microbiota were collected from 20 root canals of permanent teeth with necrotic pulps using sterile paper points. After root canal preparation, the root canals were filled with a calcium hydroxide paste for 7 days. Calcium hydroxide was removed from root canal with 2.5% sodium hypochlorite and 17% EDTA using passive ultrasonic irrigation (PUI). A second bacteriologic samples were taken with sterile paper points prior to root filling. The samples were processes with DNase-I treatment using next-generation sequencing (NGS). Reduction in bacterial numbers during root canal treatment was evaluated using real-time quantitative PCR (qPCR). All statistical analyses were conducted using the MINITAB 17 software (Minitab Ltd. Co., Coventry, UK). A one-sample t-test was used to analyse the data. Statistical significance was accepted at P < 0.05. RESULTS: Relative abundances of Mycoplasma sp., Paludibacter sp., Tannerella sp., Prevotella spp. and an uncultured species from the order Bacteroidales decreased with root canal preparation and medication (98.7%, 99.8%, 98.8%, 97.7% and 99.3%, respectively), whilst the relative abundances of Methylobacterium sp., Corynebacterium sp. and Streptococcus infantis increased (93.1%, 94.8% and 99.4%, respectively). Considerable numbers of Streptophyta species were detected before and after treatment. The ratio of Agrobacterium sp. in the treated teeth community and the ratio of order Streptophyta in the infected canals had negative correlations with the success of bacterial elimination. CONCLUSIONS: The combination of NGS and qPCR techniques resulted in detection of previously unknown components of the oral microbiome and the effects of root canal treatment on their relative abundance in a Turkish population.

Vibration paradox and H-reflex suppression: is H-reflex suppression results from distorting effect of vibration?

Vibration paradox is that an increase in muscles activity coexists with the inhibition of H-reflex during vibration. The H-reflex suppression may be due to the movement of stimulating electrode during vibration. The aim of this study was to test this hypothesis. Fifteen healthy young adult males participated in this study. The soleus myoelectrical activities were evaluated by surface electromyography (SEMG). The vibration was applied only to the left leg and the H-reflex of soleus muscle was measured in the right leg to prevent the probable measurement errors caused by the movement of stimulating electrode. The Hmax/Mmax ratio of the right soleus isolated from vibration effects significantly decreased during the left leg vibration. As a result, this study shows that the H-reflex is suppressed during the vibration and the movement of the stimulating electrode has no role on the suppression of H-reflex.

Cross-education of muscle strength: cross-training effects are not confined to untrained contralateral homologous muscle.

The aim of this study was to evaluate whether electrical muscle stimulation (EMS) on dominant wrist flexors causes an increase in the muscle strength of the contralateral wrist extensors. Twenty-three healthy, young, adult men were included in this prospective, double-blind, controlled study. Participants were randomly allocated to the EMS group or Control group. Electrodes were placed over the flexor aspect of the right forearm in both groups. In the EMS group, passive wrist extension and (EMS) that caused powerful muscle contraction were simultaneously applied. In the Control group, a conventional mode of transcutaneous electrical nerve stimulation was applied without causing any contraction. A group effect (P=0.0001) and group-by-time interaction were found (P=0.0001) for both the wrist flexor and extensor muscles, but not group-by-time-by-arm interactions. This implies that the effect of the interventions was similar in both arms, but that the response was significantly larger in the EMS than in the Control group. The results of the current study suggest that cross-education is not confined to the untrained contralateral wrist flexors and that the strength increase may also be observed in the contralateral wrist extensors.

Erectile mechanisms in man.

Increases in penile circumference during sleep-related erections in human subjects closely reflected increases in penile blood flow, and bursts of activity in the bulbocavernosus and ischiocavernosus muscles were temporally related to these increases. The penile arterial system and the perineal muscles appear to have important coordinated roles in human penile erection. Monitoring sleep-related erections and penile blood flow holds promise for the study of erectile mechanisms and dysfunction and for screening of drugs.

Testosterone replacement therapy and sleep-related erections in hypogonadal men.

Hypogonadal men usually have diminished libido and erectile dysfunction, and testosterone replacement therapy in these men increases sexual activity, erotic thoughts, and self-reported nocturnal erections. The polygraphic assessment of nocturnal penile tumescence (NPT) provides an objective index of erectile capability and is useful for differentiating psychogenic from organic erectile dysfunction. In this study we evaluated NPT in six hypogonadal adult men during and after termination of androgen therapy. Multinight sleep studies were conducted within 1 week and 7-8 weeks after each man received 20 mg testosterone cypionate, im. The mean serum testosterone level 4-7 days after testosterone injection was 35.9 +/- 3.4 (+/- SE) nmol/L, and it fell to 2.3 +/- 0.9 nmol/L after 7-8 weeks. Significant declines (P less than 0.05) in the number of NPT episodes (3.7 to 2.0), maximum penile circumference increase (24 to 13 mm), and total tumescence time (107 to 55 min) accompanied the fall in the serum testosterone level. No androgen-related changes in the amount or integrity of rapid eye movement sleep were found. Finally, the mean penile rigidity (buckling pressure) decreased from 770 +/- 98 to 590 +/- 81 g (P less than 0.05). Comparison of these results to those in normal men revealed that none of these men met all diagnostic criteria for organic impotence, even 7-8 weeks after discontinuation of testosterone administration. While men with androgen deficiency may have normal NPT, sleep-related erections increase in response to testosterone administration.

Disulfiram and nocturnal penile tumescence in the chronic alcoholic.

Thirty male sober alcoholic inpatients received placebo or disulfiram in a random double-blind design in order to evaluate the effects of disulfiram on nocturnal penile tumescence. The amount and frequency of full erections were decreased in the cohort receiving disulfiram. Implications of these results for the role of norepinephrine in penile tumescence are discussed.

Nocturnal erections, differential diagnosis of impotence, and diabetes.

In this study it is shown that monitoring of nocturnal penile tumescence (NPT) is an objective method for determining the erectile status of patients who complain of impotence. The characteristics of 11 diabetic patients with abnormal NPT, 11 patients with normal NPT and no medical disorders, and 11 normal men are presented. Also described are several sociodemographic characteristics of the first 100 patients undergoing an NPT evaluation as part of a screen for patients seeking implantation of a penile prosthesis. It is suggested that NPT monitoring should be a component of the differential diagnosis procedure for every patient who complains of impotence and that it provides a tool for the concentrated study of the mechanisms of erection and impotence.

Dose-related sleep disturbances induced by coffee and caffeine.

In a 13-night sleep laboratory study, each of 18 normal young adult males twice received 1 cup of warm water, 1-, 2-, and 4-cup equivalents of regular coffee, a 4-cup equivalent of decaffeinated coffee, and a 4-cup equivalent of caffeine. All beverages were administered 30 min before bedtime according to a balanced Latin-square design. Regular coffee produced dose-related changes in most standard electroencephalogram-electrooculogram (EEG-EOG) sleep parameters, and the 4-cup equivalents of regular coffee and caffeine produced equivalent effects. Decaffeinated coffee had no effect. Regular coffee and caffeine caused rapid eye movement (REM) sleep to shift to the early part of the night and stages 3 and 4 sleep to shift to the later part. Coffee also produced dose-related changes in several subjects estimates of sleep characteristics. These results suggest that coffee and caffeine may be used in normal subjects to induce symptoms mimicking those of insomnia. Such a tool should promote further understanding of insomnia.

Sleep-related penile tumescence as a function of age.

The authors conducted a study of nocturnal penile tumescence (NPT) in 125 healthy males aged 3 to 79 by means of EEG recordings to provide normative data on how general the phenomenon is, its range of charateristics, and how it is related to man's sexual function. The results indicate that NPT occurs consistently in a healthy male population, that its expression is significantly affected by age, that it is related to stage of psychosexual development, and that it is worthy of further investigation. Clinical experience indicates that it is a useful, objective method of discriminating among various types of biogenic and psychogenic impotence.

Nocturnal penile tumescence and diagnosis in diabetic impotence.

The authors conducted a study of nocturnal penile tumescence (NPT) in 35 diabetic men, aged 33 to 70, who complained of impotence and in 35 age-matched control subjects. EEGs and other measurements showed that the diabetic men as a group exhibited significant reductions in the total amount of NPT and in the amount and frequency of full erection, thus suggesting that impotence in this cohort was organogenic. Although NPT monitoring represents an advance over the less precise traditional procedures for the differential diagnosis of impotence, the authors stress the need for more research in this area.

Narcolepsy: regional cerebral blood flow during sleep and wakefulness.

Serial measurements of regional cerebral blood flow were made by the 135Xe inhalation method during the early stages of sleep and wakefulness in eight normal volunteers and 12 patients with narcolepsy. Electroencephalogram, electro-oculogram, and submental electromyogram were recorded simultaneously. In normals, mean hemispheric gray matter blood flow (Fg) during stages I and II sleep was significantly less (-9.2 percent) than waking values (84.3 +/- 13 ml per 100 gm brain per minute). Maximum regional blood flow decreases during sleep occurred in the brainstem-cerebellar (-25.1 percent), right inferior temporal (-23.1 percent) and bilateral frontal (-18.9 percent) regions (p less than 0.05). In patients with narcolepsy, mean hemispheric Fg while awake was 80.5 +/- 13 ml per 100 gm brain per minute. During REM sleep (n = 2), mean hemispheric Fg increased by 9.8 percent concurrently with large increases (+34.6 percent) in brainstem-cerebellar region flow. During stages I and II sleep without REM (n = 6), there were significant increases in mean hemispheric Fg of +/-20.2 percent (p less than 0.01) and brainstem-cerebellar Fg of 38.0 percent (p less than 0.01), just the opposite of changes in normals. In narcolepsy, there appears to be a reversal of normal cerebral deactivation patterns, particularly involving the brainstem, during stages I and II sleep.

Erectile dysfunction in narcoleptic patients.

Many male narcoleptic patients complain of erectile dysfunction related to chemotherapy, and some find it so distressing that they fail to continue treatments. This is a potentially dangerous situation. We studied the erectile capabilities of 28 narcoleptic men who had complaints of erectile dysfunction with our objective sleep laboratory measurement of nocturnal penile tumescence (NPT) for diagnostic workup. We found that while short REM latency, a classic indicator of narcolepsy, was present in all patients, NPT, which is associated with REM sleep, did not coincide with the short REM latencies in about half the patients. This may be partially due to the fact that first-cycle REM is often not accompanied by NPT episodes (even in the control population). We also found that, in a few cases, the patients' subjective beliefs about their erectile capacity tended to underestimate our measurements. The patients receiving drug treatment already had some vasculogenic or neurogenic genital impairment, which probably made them more vulnerable to the effects of the drugs. Patients who had none of these complications showed similar erectile impairment under the influence of medication. Additionally, we found unique manifestations of the disease in three drug-free patients; one had cataplectic attacks upon arousal, and two had unexplained erectile impairment.

Sleep spindles: pharmacological effects in humans.

In the present paper we summarize the effects of a variety of drugs on sleep spindle activity in humans. The data are derived from 16 studies conducted in our laboratories during the past several years. The Sleep Analyzing Hybrid Computer was utilized to score each record for sleep stage and spindle activity. To the best of our knowledge, this collection of data is the largest currently available on the relationship between drug administration and standardized sleep spindle parameters in normal human subjects. Ten of the studies are dose-response evaluations. We consider this design a powerful and useful approach for basic sleep pharmacology research. Marked spindle enhancement was produced by flurazepam. WE-941 (a new benzodiazepine hypnotic), methaqualone, and secobarbital. Smaller differences were found for atropine, scopolamine, and caffeine. The results are discussed with respect to drug-class differences, sleep induction properties, the current literature, and the benzodiazepine hypothesis. Some of our future research plans with respect to spindle pharmacology also are presented.

Automated measurement of alpha, beta, sigma, and theta burst characteristics.

An automatic system was used for the selection and analysis of alpha, beta, and theta waveforms occurring in the awake and REM sleep states and sleep spindles occurring in stage 2 sleep. Two nights of sleep were analyzed for each of five normal subjects in each of five age groups: 3--5; 13; 25--34; 43--53; and 67--79 years of age. The waveform frequencies, length, and rate of occurrence were measured. No age-related changes were found in the alpha frequency (except for the younger group). No significant age differences were found in the beta and theta frequencies in the awake state. During REM sleep, the average beta and theta frequencies of the two youngest groups were significantly different from those of the three older groups. The average frequency of stage 2 sleep spindles of the two youngest groups was less than that in the middle group; the average spindle frequency of this group was significantly less than that of the two older groups. The number of spindles per minute was significantly less for the younger group and significantly more for the 25- to 34-year-olds.

Differentiating psychological characteristics of patients with sleep apnea and narcolepsy.

Fifty male subjects were group-matched for age and socioeconomic status. Twenty of the subjects were diagnosed as having sleep apnea and 20 were diagnosed as having narcolepsy on the basis of sleep studies. The remaining 10 subjects served as normal controls. Differences among the groups were evaluated on the bases of two psychological instruments designed to assess personality characteristics and mood states. The findings suggest that narcoleptics and apneics both present discriminatively different psychological profiles than do normals. Moreover, personality characteristics of these two groups are distinguishable from one another. Apneics tend to be individuals with hypochondriacal and hysterical characteristics, whereas narcoleptics are more easily characterized by anxiety and social introversion. Both severity of psychological disturbance (mean Minnesota Multiphasic Personality Inventory elevations) and personality pattern (two-point codes) distinguish the groups. Key Words: Sleep apnea-Narcolepsy-Psychological profiles.

Hypertension, erectile dysfunction, and occult sleep apnea.

Sleep-related respiratory pattern was evaluated in 175 hypertensive and 110 normotensive men, none of whom reported difficulties in initiating or maintaining sleep. Patients were grouped according to sexual status (complaint of erectile problems), hypertension treatment status (treated or untreated), and blood pressure (diastolic less than 90 or greater than or equal to 90). The prevalence of sleep apnea, apnea index, duration of the longest episode of apnea, and penile rigidity were tabulated. The group with elevated blood pressure, persistent even with antihypertensive drug therapy, had the most sleep apnea. The treated hypertensive men with controlled blood pressure had significantly less apnea than those whose blood pressure remained high. Untreated hypertensive groups, however, did not differ from normotensive groups with respect to apnea. Evidence of abnormal sleep-related respiratory activity was found in both hypertensive and normotensive groups with erectile problems. Interestingly, penile rigidity was significantly lower for hypertensive men with erectile complaints than for normotensive men with erectile complaints. There was also a small, but significant, negative correlation between apnea index and penile rigidity among men with erectile complaints. These results indicate that sexual status is an important consideration in the diagnosis of hypertension and sleep apnea. Moreover, these data suggest an interrelationship among hypertension, erectile dysfunction, and sleep apnea.

Daytime sleepiness as a criterion in hypnotic medication trials: comparison of triazolam and flurazepam.

Sleep laboratory hypnotic medication trials typically determine efficacy by examining changes in polysomnographically recorded sleep. We introduce the use of daytime sleepiness, as assessed by the Multiple Sleep Latency Test (MSLT), as a criterion for daytime functioning in such trials. Two benzodiazepine hypnotics, triazolam (0.5 mg) and flurazepam (30 mg), with short and long half-lives respectively, were compared in a multicentered, double-blind crossover study. Results indicated these medications had virtually indistinguishable nocturnal effects, but differed dramatically during the day. Flurazepam decreased sleep latency on the MSLT, whereas triazolam did not. These results could indicate that daytime sleepiness is a concomitant effect of flurazepam.

Sleep-related electrodermal activity patterns in impotent patients.

The etiology of erectile failure is not always clear despite the fact that recordings of nocturnal penile tumescence (NPT) are used to detect patients with a significant organic component to their complaint. We recorded electrodermal activity in addition to NPT in 60 impotent patients. Normally more electrodermal activity occurs in stage 2 than in stage REM sleep. Despite a similar total amount of electrodermal activity, organically impotent patients tended to have less electrodermal activity in stage 2 and more in stage REM sleep than those with normal NPT. This difference was due to a subgroup of 15 organically impotent patients with less electrodermal activity in stage 2 than in stage REM sleep. Because of this difference in the pattern of electrodermal activity in relation to sleep stages, the results suggest a central nervous system change is related to impaired erectile capability and abnormal NPT in these cases.

Uterine activity during sleep.

REM-related increases in uterine activity were found in 10 healthy young adult volunteer subjects. Contraction baseline pressures were elevated compared with NREM sleep, stage 2 sleep, stages 3 and 4 slow wave sleep (SWS), and stage 0. Contraction amplitudes during REM sleep were greater than those during SWS and stage 0, while contraction rates differed only between REM sleep and SWS. The results strongly indicated a cycle of genital activity in women that parallels the penile erection cycle in men. The implications of this finding and suggestions for future research are discussed.

Diabetes, erectile dysfunction, and sleep-related erections.

Sleep-related erections were assessed in conjunction with polysomnography in 100 diabetic and 400 nondiabetic men with complaints of erectile problems. We also measured bulbocavernosus reflex latency, heart rate response to deep breathing, postural-related blood pressure changes, penile arterial sufficiency, and brachial blood pressures. To investigate the relationship between diabetes and erectile capacity, the results obtained from men with and without diabetes were compared. Men with diabetes had fewer sleep-related erections, less tumescence time, diminished penile circumference increase, and lower penile rigidity than nondiabetic men. These diabetes-related differences were found regardless of the maximum penile rigidity observed. The diabetic group had less heart rate response to deep breathing and lower penile blood pressures than the nondiabetic group, but only among men with maximum penile rigidity less than 500 g. These data indicate that both neurological and vascular mechanisms are involved to a greater degree in organic diabetic impotence than in the organic erectile dysfunction that occurs in nondiabetic men. Finally, the pattern of lower values for measures of nocturnal tumescence among diabetic men, compared to nondiabetic men, occurred in all age groups, except the oldest. Among impotent men, age 65 years or older, no difference was found between men with and without diabetes. This suggests that diabetes may foreshadow some of the age-related pathophysiological processes associated with erectile dysfunction.