Electron microscopy and tomography reveal that sodium 2-naphthalene sulfonate incorporated into perming solutions swells and tilts trichocyte intermediate filaments causing straightening of curly Japanese human hair.

OBJECTIVE: A new hair-care process has been specifically developed for the straightening of curved Japanese woman's hair . The process included sodium 2-naphthalene sulfonate (SNS) in the reduction and oxidation steps of a conventional perming process. Our objective was to develop an understanding of how this process caused hair straightening by measuring the changes to morphology and ultrastructure between untreated, conventionally permed and SNS permed hair. Untreated and SNS permed Merino wool fibres were used to confirm structural changes. METHODS: Japanese hair samples were measured for single-fibre curvature before and after perming treatments. A silver staining method was developed to stain hair fibres without changing fibre curvature so that transmission electron microscopy could be used to measure changes in the lateral dimensions of all structural components from the cellular to protein filament level. Electron tomography determined intermediate filament slopes and slope changes after SNS perming relative to the central longitudinal axis of the fibre. RESULTS: SNS perming was found to cause greater lateral swelling than conventional perming of: the paracortical cells of wool; the cuticle, the cuticular cell membrane complex and the macrofibrillar centre-to-centre distance of hair; and of the intermediate filaments in wool and hair. In curved hair, SNS perming caused the intermediate filaments of the helical macrofibrils to simultaneously swell and to tilt further, resulting in the slight longitudinal contraction of the macrofibrils. The overall swelling and tilting was greatest in the helical macrofibrils of Type B cortical cells predominately located in the convex fibre half. The presence of a higher percentage of helical macrofibrils in the convex fibre half than in the concave fibre half caused a contraction differential between the two halves leading to straighten of the curved fibre. A mechanical model was proposed to explain how SNS perming straightened curly hair. CONCLUSION: The effects of conventional and SNS perming on the morphological and ultrastructural components of curved Japanese hair and high-curl Merino wool fibres have given clear insights into understanding the mechanism of fibre curvature change.

OBJECTIF: Un nouveau procédé de soin des cheveux a été spécialement conçu pour lisser les cheveux ondulés des Japonaises[1]. Le procédé utilise le sulfonate de naphthalène-2 sodium (SNS) dans les étapes de réduction et d'oxydation du procédé conventionnel de permanente. Notre objectif était de comprendre la façon dont ce procédé induisait le lissage des cheveux en mesurant les différences de changement morphologique et ultrastructural entre les cheveux non traités et ceux soumis à une permanente conventionnelle et une permanente à base de SNS. Des fibres de laine de mérinos non traitées et soumises à une permanente à base de SNS ont été utilisées pour confirmer les changements structurels. MÉTHODES: Des échantillons de cheveux japonais ont été utilisés pour mesurer la courbure d'une fibre isolée avant et après le traitement de permanente. Une méthode de coloration argent a été mise au point pour colorer les fibres de cheveux sans changer la courbure des fibres afin de pouvoir utiliser la microscopie électronique en transmission pour mesurer les modifications des dimensions en largeur de tous les composants structurels du filament, de la cellule aux protéines. Une tomographie électronique a déterminé les pentes intermédiaires et les changements de pente des filaments après permanente à base de SNS par rapport à l'axe longitudinal central de la fibre. RÉSULTATS: On a constaté que la permanente à base de SNS induisait un gonflement en largeur plus important que la permanente classique des cellules paracorticales de la laine; de la cuticule, du complexe de la membrane cellulaire cuticulaire et de la distance centre à centre des macrofibrilles du cheveu; et des filaments intermédiaires dans la laine et les cheveux. Dans les cheveux ondulés, la permanente à base de SNS a provoqué à la fois un gonflement et une inclinaison des filaments intermédiaires des macrofibrilles hélicoïdales, entraînant une légère contraction longitudinale des macrofibrilles. Au total, le gonflement et l'inclinaison étaient plus importants dans les macrofibrilles hélicoïdales des cellules corticales de type B situées principalement dans la moitié convexe de la fibre. La présence d'un pourcentage plus élevé de macrofibrilles hélicoïdales dans la moitié convexe par rapport à la moitié concave de la fibre a entraîné une contraction différentielle entre les deux moitiés qui a entraîné le redressement de la fibre courbée. Un modèle mécanique a été proposé pour expliquer comment la permanente à base de SNS lissait les cheveux bouclés. CONCLUSION: Les effets de la permanente conventionnelle et à base de SNS sur les composants morphologiques et ultrastructuraux des cheveux japonais ondulés et des fibres de laine très frisés de mérinos ont permis de mieux comprendre le mécanisme du changement de courbure des fibres.

The physical and chemical disruption of human hair after bleaching - studies by transmission electron microscopy and redox proteomics.

OBJECTIVE: To understand the structural and chemical effects of cosmetic peroxide bleaching on human hair. METHODS: Human hair was progressively bleached using alkaline peroxide-persulphate treatment. Proteins lost through leaching were examined using amino acid analysis and mass spectrometric sequencing. Fibre damage was assessed using transmission electron microscopy, amino acid analysis and redox proteomics. RESULTS: Protein loss through leaching increased with bleaching severity. Leached proteins were not limited to the cuticle, but also included cortical intermediate filaments and matrix keratin-associated proteins. The leached proteins were progressively oxidized as bleaching severity increased. Bleached fibres demonstrated substantial damage to the cuticle layers and to the cortex. Extensive melanin granule degradation was present after the mildest bleach treatment. Protein oxidation in bleached fibres was principally in cortical intermediate filaments - the most abundant hair proteins - and targeted the sulphur-containing amino acids, particularly the conversion of cystine disulphide bonds to cysteic acid. CONCLUSION: Peroxide chemical treatments quickly access the cortex, causing untargeted oxidative damage across the fibre in addition to the desired loss of melanin. Peroxide ingress is likely facilitated by the considerable structural degradation caused to the cuticle layers of hair fibres. The consequences of the peroxide action within the cuticle and cortex are oxidation of the proteins, and subsequent protein loss from the fibre that correlates to bleaching severity.

Efficacy and safety of antidepressant augmentation of continued antipsychotic treatment in patients with schizophrenia.

OBJECTIVE: To evaluate the efficacy and safety of antidepressant augmentation of antipsychotics in schizophrenia. METHODS: Systematic literature search (PubMed/MEDLINE/PsycINFO/Cochrane Library) from database inception until 10/10/2017 for randomized, double-blind, efficacy-focused trials comparing adjunctive antidepressants vs. placebo in schizophrenia. RESULTS: In a random-effects meta-analysis (studies = 42, n = 1934, duration = 10.1 ± 8.1 weeks), antidepressant augmentation outperformed placebo regarding total symptom reduction [standardized mean difference (SMD) = -0.37, 95% confidence interval (CI) = -0.57 to -0.17, P < 0.001], driven by negative (SMD = -0.25, 95% CI = -0.44-0.06, P = 0.010), but not positive (P = 0.190) or general (P = 0.089) symptom reduction. Superiority regarding negative symptoms was confirmed in studies augmenting first-generation antipsychotics (FGAs) (SMD = -0.42, 95% CI = -0.77, -0.07, P = 0.019), but not second-generation antipsychotics (P = 0.144). Uniquely, superiority in total symptom reduction by NaSSAs (SMD = -0.71, 95% CI = -1.21, -0.20, P = 0.006) was not driven by negative (P = 0.438), but by positive symptom reduction (SMD = -0.43, 95% CI = -0.77, -0.09, P = 0.012). Antidepressants did not improve depressive symptoms more than placebo (P = 0.185). Except for more dry mouth [risk ratio (RR) = 1.57, 95% CI = 1.04-2.36, P = 0.03], antidepressant augmentation was not associated with more adverse events or all-cause/specific-cause discontinuation. CONCLUSIONS: For schizophrenia patients on stable antipsychotic treatment, adjunctive antidepressants are effective for total and particularly negative symptom reduction. However, effects are small-to-medium, differ across antidepressants, and negative symptom improvement seems restricted to the augmentation of FGAs.

Redox proteomic evaluation of bleaching and alkali damage in human hair.

OBJECTIVE: Protein modification and damage in human hair, resulting from environmental, cosmetic and grooming stresses, create changes to visual and tactile characteristics and correlates with consumer perception of quality. This study outlines molecular-level evaluation of modification resulting from peroxide (bleaching) and alkaline straightening (relaxing) treatments. METHODS: Redox proteomic profiling of virgin, bleached and relaxed hair tresses was performed, with comprehensive qualitative characterization of modification and semi-quantitative evaluation of damage through adaptation of a new damage scoring system. Modifications were mapped to specific locations in the hair proteome and a range of potential damage marker peptides identified. RESULTS: Virgin hair contained a baseline level of modification, consistent with environmental oxidative insult during hair growth. Hydrogen peroxide bleaching resulted in significantly increased levels of oxidative damage observable at the molecular level. This treatment also resulted in enhanced levels of dehydroalanine and dehydration products; modifications typically associated with alkali or thermal treatment and not previously been reported as a product of hair bleaching. Relaxation treatment with sodium hydroxide increased the formation of dehydroalanine and dehydration products and moderately enhanced the levels of oxidation. Cysteine was the predominant modification site for both bleaching and alkali damage. CONCLUSION: This study validates the utility and power of redox proteomic-based approaches to characterizing hair modification. This offers potential application to a wide range of damage types, as well as evaluation of new damage mitigation and repair technologies.

Transmission electron microscopy staining methods for the cortex of human hair: a modified osmium method and comparison with other stains.

For wool, superior staining of a wide range of ultrastructural components is achieved by en bloc treatment of fibres with a chemical reductant followed by osmium tetroxide. For human scalp hair, although staining quality is similar, the penetration of reagents is poor, resulting in large parts of the fibre cortex remaining unstained. Here we describe a modification to the reduction-osmication method in which reagents penetrate through a cut fibre end, allowing visualization of a wide range of features across the cortex. We compare the staining quality, artefacts and range of structure rendered visible using transmission electron microscopy for en bloc reduction-osmication to other staining alternatives including en bloc silver nitrate and section stains based on uranyl acetate and lead citrate, phosphotungstic acid, potassium permanganate, ammoniacal silver nitrate and some combinations of these stains. The effects of hair-care treatments are briefly examined.

Morphology and ultrastructure of antler velvet hair and body hair from red deer (Cervus elaphus).

We provide a detailed description of the ultrastructure of deer hair fibers. Guard hairs and underhairs from the winter coat of red deer (Cervus elaphus), and antler velvet hairs from the same species were examined. All fibers displayed the typical keratin fiber morphology of overlapping cuticle cells surrounding a core of cortex cells, and often a centrally-located medulla, but there were considerable differences in the diameter, cuticle thickness, and scale pattern, and in the relative amounts of cortex and medulla along individual fibers, and between the different types of fiber. In addition, closer examination of cortex cells using transmission electron microscopy revealed considerable differences in the arrangement of intermediate filaments in the different fiber types. Fine underhairs appeared similar to fine wool fibers from sheep because intermediate filament arrangements were very similar to those found in wool orthocortex cells and paracortex cells. In addition, a similar bilateral distribution of these cell types was evident. However, in the antler velvet hairs and the guard hairs, intermediate filament arrangements were more variable and complex, and showed similarities to those in heterotype cortex cells described for human hair.

Clinical trial to compare tinnitus masking and tinnitus retraining therapy.

CONCLUSION: Both tinnitus masking (TM) and tinnitus retraining therapy (TRT) can be effective therapies for amelioration of tinnitus. TM may be more effective for patients in the short term, but with continued treatment TRT may produce the greatest effects. OBJECTIVES: Although TM and TRT have been used for many years, research has not documented definitively the efficacy of these methods. The present study was a controlled clinical trial to prospectively evaluate the clinical efficacy of these two methods for US military veterans with severe tinnitus. SUBJECTS AND METHODS: Over 800 veterans were screened to ensure that enrolled patients had tinnitus of sufficient severity to justify 18 months of individualized treatment. Qualifying patients (n=123) were placed quasi-randomly (alternating placement) into treatment with either TM or TRT. Treatment was administered at 0, 3, 6, 12, and 18 months. Outcomes of treatment were evaluated primarily using three self-administered tinnitus questionnaires (Tinnitus Handicap Inventory, Tinnitus Handicap Questionnaire, Tinnitus Severity Index). RESULTS: Findings are presented from the three written questionnaires with respect to three categories of patients: describing tinnitus as a 'moderate,' 'big,' and 'very big' problem at baseline. Based on effect sizes, both groups showed considerable improvement overall. In general, TM effects remained fairly constant over time while TRT effects improved incrementally. For the patients with a 'moderate' and 'big' problem, TM provided the greatest benefit at 3 and 6 months; benefit to these TRT patients was slightly greater at 12 months, and much greater at 18 months. For patients with a 'very big' problem, TM provided the greatest benefit at 3 months. For these latter patients, results were about the same between groups at 6 months, and improvement for TRT was much greater at 12 months, with further gains at 18 months.

Masking of tinnitus through a cochlear implant.

The relief of tinnitus has been effected in a cochlear-implant patient by presenting masking sounds to the microphone of the implant. Oddly enough, the presence of the masking sound improved the clarity of speech and music.

Characteristics of tinnitus induced by head injury.

OBJECTIVE: To determine if the characteristics of tinnitus produced by head trauma are specific and exclusive when compared with other origins of tinnitus. DESIGN: Retrospective study using clinic test results and data from the Tinnitus Data Registry compiled from questionnaires, interviews, and testing. Tinnitus produced by head injury was compared with tinnitus of mixed origins, including no known origin. SETTING: A tinnitus referral clinic where all patients must see an otologist or an ear, nose, and throat physician prior to attending the clinic. PATIENTS: All patients had severe to moderately severe constant tinnitus and presented with tinnitus as the primary symptom. RESULTS: No exclusive characteristics were found to describe head injury-induced tinnitus. The tinnitus for the group with head injury was statistically significantly (P = .004) louder and occurred with greater incidence of continuing pain in the ears. The group with head injury also had more episodes of dizziness and a more severe form of tinnitus. However, no marked difference was noted in pitch of tinnitus, complexity (number of sounds) of tinnitus, or the minimum masking level. CONCLUSIONS: This retrospective study found that tinnitus induced by head injury was significantly (P = .004) louder than tinnitus induced from other causes but, interestingly, did not require higher levels of masking. The patients with head injury-induced tinnitus more frequently (P = .0003) displayed residual inhibition although the duration of residual inhibition was not different from that of the comparison group. Other symptoms associated with the tinnitus onset were more frequently mentioned by the group with head trauma-induced tinnitus, except for the condition of pressure sensation in the ears. Using a severity questionnaire, the group with head trauma-induced tinnitus rated their tinnitus as being more severe than did the comparison group. However, such things as pitch of the tinnitus, masking level, acceptance of wearable maskers, general hearing level, and complexity of the tinnitus did not distinguish the two groups.

Measuring tinnitus parameters: loudness, pitch, and maskability.

Improved procedures have been developed for obtaining hearing thresholds, loudness matches, pitch matches, and masking curves of tinnitus. Computer programs enable all of these measures to be obtained in a single session. These measures have been obtained in tinnitus and nontinnitus subjects, with an external stimulus used to simulate tinnitus in nontinnitus subjects. These measures, obtained in repeated sessions, were used to determine the test-retest variability of each measure. The test-retest standard error of measurement, across-subjects, is reported, which enables changes in tinnitus to be determined. In nontinnitus subjects, the accuracy, as well as the reliability, is described.

Pathophysiology of tinnitus: a special case--hyperacusis and a proposed treatment.

The occurrence of hyperacusis is rare. In our Tinnitus Clinic, where more than 4,000 patients have been seen, hyperacusis has been seen only four times. Treatment of hyperacusis has been a combination of protection from external sounds along with desensitization to sound. Desensitization has been produced by very low intensity masking which is gradually increased every two to four weeks. The process of desensitization requires a great deal of time.

Attempts to suppress tinnitus with transcutaneous electrical stimulation.

Various electrical stimuli were tested for their ability to suppress or relieve severe tinnitus. Stimulation was applied transdermally by electrodes placed on the preauricular and postauricular regions and on the two mastoids. Of the 50 patients tested, only 14 (28%) obtained relief that met the criterion of a reduction in the tinnitus by 40% or more. When relief was obtained, it usually extended for several hours into the poststimulation period. There was only one positive response (2%) in the placebo trial, which was administered to all patients. It was concluded that transdermal electrical stimulation such as that used in this research is not a practical therapeutic procedure for the relief of tinnitus.

Research in tinnitus. A report of progress.

As one reviews the contents of this presentation, one finds there are no dramatic "breakthroughs" and there are frequent examples of neutral or negative findings. One should not let this state of affairs discourage continued research. It is often the case that many mistrials are encountered when investigating an area where very little is known. We expect research on tinnitus to proceed at a slow pace, but under no circumstances should the research effort in tinnitus be curtailed.

Reduction of acoustically-induced auditory impairment by inhalation of carbogen gas. I. Permanent noise-induced cochlear damage.

The possible beneficial effects of carbogen gas (95% O2/5% CO2) inhalation on noise-induced permanent cochlear impairment were investigated. Groups of guinea pigs were exposed to daily 3 1/2-hour presentations of 120 dB of broad-band noise in an atmosphere of either carbogen gas or normal air. Other groups received carbogen or normal air with a low intensity (50 dB) acoustic exposure. After a 30-day stabilization period each ear was examined electrophysiologically and histologically. Measures included a.c. cochlear potentials from 100 Hz through 20 kHz as well as counts of missing inner hair cells (IHCs) and outer hair cells (OHCs). Statistically significant improvement in the 1 microV isopotential function of the a.c. cochlear potential over all test frequencies and significant reduction in the number of missing IHCs and OHCs was found to result from inhalation of carbogen gas. Blood gas analysis demonstrated a rapid and marked elevation in arterial PCO2 and PO2 with a corresponding drop in pH to result from inhalation of carbogen. The vasodilating effects of increased arterial carbon dioxide tension are discussed in terms of current speculations regarding the role of vasoconstriction in noise-induced hearing loss.

Tinnitus masking:unresolved problems.

With care to provide properly chosen masking sounds, masking can help in 60-80% of clinically significant tinnitus cases. There is no universal masker; instead, an individual evaluation of each patient's tinnitus must be performed in order to match the masking sounds to the patient's audiogram and the spectral characteristics of the tinnitus. Successful long-term masking can usually be achieved in patients for whom (1) hearing impairment is not excessive. (2) the tinnitus frequency, FT, can be reliably located, and (3) the tinnitus can be completely masked by a band of noise at or near FT at a low sensation level. Such patients often experience residual inhibition (temporary suppression of tinnitus upon cessation of masking) which may accumulate with sustained use of masking, in some cases becoming permanent. Long-term masking is difficult or impossible for patients whose hearing is so impaired they cannot hear the masker, or those for whom the masking sounds must be presented at unacceptably loud levels to obtain adequate coverage of the tinnitus. There is a great need for additional work to determine what factors influence the effectiveness of masking, in order to improve our ability to provide appropriate masking stimuli even for the difficult cases.

Evaluation of a tinnitus masking program: a follow-up study of 598 patients.

A follow-up study of two groups of tinnitus patients was conducted in an attempt to evaluate the tinnitus masking program. Results are discussed separately for a group of patients seen during the first three years of the program (1976 through 1978) and during the last year (1979). These results suggest an improvement in the management of the tinnitus patient and support this procedure as a viable technique in providing relief for selected tinnitus patients.