Principles for the safety evaluation of cosmetic powders.

Consumer exposure to cosmetic (personal care) products is mostly by dermal contact, however additional considerations with regards to potential inhalation exposure from some cosmetics, such as sprays and powders, may be needed for a robust and reliable safety assessment. To get a deeper understanding of the exposure to airborne particles and droplets during product application, a team of international experts was founded under the umbrella of the European Association of the Cosmetic Industry "Cosmetics Europe" (CE) in Brussels. This expert team has worked out a pragmatic strategy how small and medium sized enterprises (SMEs), but also relevant authorities, could handle the safety evaluation of cosmetic powder products. Sufficient information on the aerodynamic diameter of sprayed droplets and here specifically of airborne particles is essential in addition to knowing the exposure after typical product application. The current article is focused on the determination of inhalation exposure to solids, and the derivation of safe exposure levels for cosmetic powder products found in the market. The principles described herein are very similar to spray products as published earlier and should be applied in a similar way (Steiling et al., 2014). Prediction models for the best estimate of inhalation exposure, developed with data from computer simulation programs, individual real-time measurements or finally by experience from the market were introduced and applied. Safety assessment approaches for exposure from powder spray products were developed and have been already considered in regulatory guidelines like the EC Cosmetics Regulation.

A comparison of breast muscle characteristics in three broiler great-grandparent lines.

Genetic selection of broiler chickens has led to a gross overdevelopment of the broiler breast muscle pectoralis major. This may have resulted in increased myopathy and detrimental effects on meat quality. The present study examined 3 commercial great-grandparent lines (lines A, B, and C). Lines A and B are female lines, and line C is a male line. The mean BW of line C (2.7 kg) was significantly greater than those of lines A and B (both 2.3 kg). However, the mean breast yield of both lines B and C (8.9 and 8.7%, respectively) was significantly greater than that of line A (6.9%). Line B therefore matched the meat yield of line A while maintaining a high reproductive capacity. The mean breast fillet weight of line A (169 g) was significantly lower than lines B (207 g) and C (235 g). No differences were observed between lines in either mean fiber size or amount of connective tissue. Therefore, additional fibers must provide the additional weight in the breast fillet of lines B and C, compared with A. Plasma creatine kinase activity, a commonly used marker of muscle damage, was significantly higher in line A (1368 IU/L) than in lines B (995 IU/L) and C (982 IU/L). However, qualitative evaluations of muscle pathology revealed no differences among lines. Selection for increased embryonic muscle fiber number, rather than for increased radial fiber growth, could improve growth potential and may also alleviate muscle damage.

Bladder muscle biopsy and urethral sphincter EMG in patients with bladder dysfunction after pelvic surgery.

Eleven patients who suffered persistent bladder dysfunction after pelvic surgery have been investigated by needle urethral sphincter electromyography (EMG) and bladder muscle biopsy, and the results compared with those obtained in a series of controls. Individual motor units recorded from the urethral sphincter in patients who had undergone pelvic surgery were strikingly abnormal, suggesting the presence of reinnervation, and the density of detrusor innervation was significantly reduced. However, since reduction in the density of detrusor innervation may occur in circumstances other than peripheral nerve injury, we conclude that urethral sphincter EMG provides the most effective means of assessing damage to vesico-urethral innervation as a result of previous pelvic surgery.

Confirmation of in vitro and clinical safety assessment of behentrimonium chloride-containing leave-on body lotions using post-marketing adverse event data.

Behentrimonium chloride (BTC) is a straight-chain alkyltrimonium chloride compound commonly used as an antistatic, hair conditioning, emulsifier, or preservative agent in personal care products. Although the European Union recently restricted the use of alkyltrimonium chlorides and bromides as preservatives to ≤0.1%, these compounds have been safely used for many years at ≤5% in hundreds of cosmetic products for other uses than as a preservative. In vitro, clinical, and controlled consumer usage tests in barrier-impaired individuals were conducted to determine if whole body, leave-on skin care products containing 1-5% BTC cause dermal irritation or any other skin reaction with use. BTC-containing formulations were predicted to be non-irritants by the EpiDerm® skin irritation test and the bovine corneal opacity and permeability (BCOP)/chorioallantoic membrane vascular assay (CAMVA) ocular irritation test battery. No evidence of allergic contact dermatitis or cumulative dermal irritation was noted under the exaggerated conditions of human occlusive patch tests. No clinically assessed or self-reported adverse reactions were noted in adults or children with atopic, eczematous, and/or xerotic skin during two-week and four-week monitored home usage studies. These results were confirmed by post-marketing data for five body lotions, which showed only 0.69 undesirable effects (mostly skin irritation) reported per million shipped consumer units during 2006-2011; a value consistent with a non-irritating body lotion. No serious undesirable effects were reported during in-market use of the products. Therefore, if formulated in appropriate conditions at 1-5%, BTC will not cause dermal irritation or delayed contact sensitization when used in a whole-body, leave-on product.

Skeletal muscle fibre growth and growth associated myopathy in the domestic chicken (Gallus domesticus).

1. Genetic selection of broilers may have pushed muscle fibres to their maximum functional size constraints. Broiler (B), female great-grandparent (GGP) and layer (L) lines were weighed, blood sampled and killed from 5 to 25 weeks of age. 2. At 25 weeks, Pectoralis major (Pm) fibre size reached by the B (65.9 microm) and GGP (59.8 microm) were 1.5 times greater than the L (38.1 microm). In the B and GGP lines, fibre growth of the Pm markedly exceeded that of the Biceps femoris (Bf) muscle. However, in the L line, fibre growth of the Pm and Bf muscle was comparable. Connective tissue content was generally higher in the Bf than in the Pm of all lines. 3. Centralised nuclei were observed predominantly in Pm, and may regulate fibre size. Both large muscle fibres and inadequate capillary supply may induce metabolic stress in B and GGP lines due to the large diffusion distances for oxygen, metabolites and waste products. 4. Enzyme markers of muscle damage (creatine kinase (CK), lactate dehydrogenase (LDH) and aspartate aminotransaminase (AST)) and histopathological analysis of Pm and Bf indicated greater myopathy in B and GGP vs L. 5. Regenerative processes were associated with oestrogen secretion. Reduced CK and LDH preceded egg yolk precursor production and increased calcium uptake for eggshell synthesis in all three lines. Oestrogen may stimulate muscle fibre regeneration and recovery as a myo-protective adaptation to potentially detrimental changes in calcium economy during egg production.

The legal advantage of disability management.

Actively working with disabled workers to try to accommodate their needs and limitations--even if accommodation proves impossible--provides powerful protection from ADA lawsuits.

Smooth muscle in the wall of the developing human urinary bladder and urethra.

A series of human fetal and neonatal specimens ranging in age from the second month of intrauterine development to 4 1/2 years after birth has been examined using histological and histochemical techniques. In both sexes histologically differentiated smooth muscle cells were evident in the bladder wall from the 52 mm crown-rump length stage onwards--urethral smooth muscle was not distinguishable until 119 mm crown-rump length. In addition to relatively late differentiation, urethral smooth muscle was histochemically distinct from the urinary bladder detrusor muscle. Sex differences in the arrangement and innervation of smooth muscle in the proximal urethra have also been observed, and these findings lend support to the presence of a pre-prostatic urethra sphincter. It seems likely that this sphincter acts principally to prevent reflux of ejaculate into the bladder during seminal emission.

A comparison between the physiological and histochemical characterisation of urethral striated muscle in the guinea pig.

In this in vitro study comparison has been made between the actomyosin ATPase activity and the contractile properties of the external urethral sphincter in the guinea pig. Histochemical analysis showed the external urethral sphincter to contain a mixture of alkali and acid stable actomyosin ATPase positive fibres in the ratio of 3:1. External urethral sphincter isometric contraction measurements were undertaken using specimens mounted transversely or longitudinally with respect to the urethral lumen. These contraction parameters have shown that the majority of fibres which constitute the external urethral sphincter correspond to the fast twitch type. In order to determine whether the relatively small fibre diameter of urethral striated muscle influenced the contraction results, when compared with controls, corrections for different volume ratios of slow and fast fibres were applied to the results. These modified values revealed close correlation between muscle fibre actomyosin ATPase content and isometric contraction responses.

Morphological and morphometric studies of the human obstructed, trabeculated urinary bladder.

As part of an ongoing study on trabeculation of the human urinary bladder, morphological and morphometric techniques have been employed on biopsy samples of detrusor muscle removed from control and urodynamically obstructed patients. In control material the mean profile area, profile diameter and nucleated profile percentage of bladder smooth muscle cells were determined. The values of the same parameters were obtained for smooth muscle cells in samples from urodynamically obstructed and endoscopically trabeculated patients. Comparison of the results obtained from the two groups showed that smooth muscle cells undergo compensatory hypertrophy in response to outflow obstruction. Furthermore, connective tissue infiltration of detrusor muscle bundles is a characteristic of those bladders which possess cells showing the largest increase in cell size.

Quantitative study of phenol as a neurolytic agent in the urinary bladder.

The endoscopic subtrigonal injection of a 6% aqueous phenol solution is an effective technique for denervating the bladder but its clinical usefulness is limited by unpredictable side effects. This study explored the possibility of making this procedure safer by comparing the neurolytic effects of different concentrations and carriers of phenol. Phenol in 2.5 and 5% solutions in three different carriers (water, glycerine and oil) was injected into the rectovesical pouch in 35 rats. After 3 weeks the bladders were excised and the effects on the density of acetylcholinesterase-positive nerves were assessed in each animal using morphometric techniques. The density of enzyme-containing nerves was reduced by 20% in the phenolised animals when compared with controls. This reduction was maximum when water was used as the carrier for either 2.5 or 5% phenol solutions.

Intramural ganglia of the human urinary bladder.

The arrangement and distribution of intramural autonomic ganglion cells have been examined in samples of the dome and lateral walls of the human urinary bladder. Ganglia were frequently observed in samples removed from either site and possessed histochemical characteristics to support their classification as presumptive cholinergic neurons. Unlike pelvic autonomic neurons, intramural bladder ganglion cells are not associated with noradrenergic (possibly inhibitory) preganglionic nerve terminals. The widespread distribution of ganglion cells within the bladder wall serves to frustrate surgical attempts to denervate detrusor smooth muscle. The outcome of such operative procedures is likely to result in decentralisation rather than denervation of the urinary bladder.

A stone farm: development of a method for simultaneous production of multiple calcium oxalate stones in vitro.

We have previously shown how individual calcium oxalate stones of about 1 cm can be grown in vitro. While this proved a design concept, it was severely limited as an experimental tool because of the time required to undertake comparative studies. Here we describe a development of this system in which six parallel pairs of stone generators are supplied with feed solutions generating a medium that is supersaturated with calcium oxalate. Twelve stones were grown simultaneously in aseptically prepared artificial urine over a period of 32 days from 100 mg to about 250 mg. Flow rates, pH and [Ca(2+)] were stable and reproducible over the course of the experiment. Sodium azide (0.02%) was included in the growth medium of six stones and caused a modest decrease in growth rate from 5.5 to 3.4 mg/day. The experimental design is such that this was readily detectable both visually and statistically ( p<0.001). This multiple stone growing system ("a stone farm") shows improved consistency and illustrates the statistical power of the technique. Azide has only a minor effect on the growth kinetics and can be used as an antibacterial agent in studies involving urinary macromolecules. The technique is suitable for practical and meaningful investigation of calcium oxalate stone formation in vitro.

The innervation of the human prostate gland--the changes associated with benign enlargement.

Different regions of the prostate gland, namely prostatic capsule, peripheral prostate and central prostate (subdivided into proximal (near the bladder neck), distal (near the verumontanum) and midway between these areas) were obtained from 32 obstructed (stable obstructed, n = 8; unstable obstructed, n = 13; acute retention, n = 11) and five control patients. The innervation of these tissues was studied both histochemically to localise acetylcholinesterase activity and immunohistochemically for dopamine-beta-hydroxylase, 5-hydroxytryptamine, vasoactive intestinal polypeptide, neuropeptide Y, leu- and met-enkephalin, calcitonin gene-related peptide, substance P and somatostatin. In control patients the greatest density of nerves was found in the proximal central prostate, followed by the anterior capsule and distal central prostate, with the least density in the peripheral prostate. The greatest density of nerves were acetylcholinesterase positive and immunoreactive to neuropeptide Y followed (in decreasing order) by nerves immunoreactive to: vasoactive intestinal polypeptide and dopamine beta-hydroxylase; leu-enkephalin and 5-hydroxytryptamine; calcitonin gene-related peptide; met-enkephalin; substance P; somatostatin. In addition a group of periacinar 5-hydroxytryptamine-immunoreactive cells and ganglia containing acetylcholinesterase, dopamine beta-hydroxylase and all of the peptides studied except somatostatin were identified. In the prostate gland from obstructed patients there was a significant reduction in the density of acetylcholinesterase-positive nerves (p less than 0.001) when compared with the controls. A similar trend was found for dopamine beta-hydroxylase, 5-hydroxytryptamine and all of the putative neuropeptides in most areas of the prostate, the most notable exceptions being in the peripheral prostate, with an increase in dopamine beta-hydroxylase- and leu-enkephalin-immunoreactive nerves in all three groups of obstructed patients an an increase in vasoactive intestinal polypeptide- and calcitonin gene-related peptide-immunoreactive nerves in those presenting in urinary retention. The functional significance of these findings is discussed.

Decrease in the autonomic innervation of human detrusor muscle in outflow obstruction.

In a group of patients in whom bladder outflow obstruction had been confirmed urodynamically, quantitative assessment of the amount of autonomic nerve in detrusor biopsy samples has been carried out using light and electron microscope techniques. In each specimen allowance was made for muscle cell hypertrophy and increases in connective tissue, both of which occurred in response to bladder outflow obstruction. Similar quantitative assessment was performed on bladder biopsy samples from a group of unobstructed 'control' patients. When the results from the two groups were compared a statistically significant reduction in the amount of autonomic nerve supplying detrusor muscle was demonstrated in the obstructed group. This finding provides additional evidence that functional impairment of the urinary bladder occurs in response to outflow obstruction and emphasizes the need for prompt relief of the condition.

The fine structure of autonomic neurons in the wall of the human urinary bladder.

Using fresh biopsy specimens, intramural ganglia of the human urinary bladder have been examined by electron microscopy. The fine structural features of these neurons were compatible with their classification as parasympathetic in type. In several ganglia, groups of neurons were observed lying in close apposition to one another without any intervening satellite cell cytoplasm. Apart from occasional septate junctions the apposing membranes lacked any specialisation. The majority of terminals occurring in association with these intramural neurons were axosomatic in location. The terminals contained numerous small agranular and occasional large granulated vesicles and structurally were presumptive cholinergic in type. Occasional axon varicosities packed with a heterogeneous population of small agranular vesicles, large vesicles of variable density and multivesicular bodies lay in close association with the ganglion cells. The functional significance of these morphological features in terms of ganglionic transmission has been considered.

The pathogenesis of genitourinary prolapse and stress incontinence of urine. A histological and histochemical study.

Histological and histochemical analysis of biopsy samples of pubococcygeus muscle obtained from asymptomatic women and from women with stress incontinence of urine, with or without genitourinary prolapse, have been compared. In the asymptomatic women both age and parity appeared to be related to the morphological features of the samples and in particular those obtained from the posterior part of the pubococcygeus. In the symptomatic women there was a significant increase in the number of muscle fibres showing pathological damage which were obtained from the posterior part of the pelvic floor. The range of diameters of both Type I and Type II fibres obtained from this region was significantly different between symptomatic and asymptomatic women. These findings may be attributable to partial denervation of the pelvic floor in patients with urinary stress incontinence with or without genital tract prolapse.

The effects of vasectomy on the autonomic innervation of the human vas deferens.

Neurohistochemical and fine structural techniques have been employed to examine the intramural autonomic innervation of the human vas deferens following surgical division of the duct one to 15 years previously. Samples from sites on the distal (testicular) and proximal (urethral) aspects of the original vasectomy have been compared with control specimens obtained at vasectomy as to the arrangement and distribution of autonomic nerves. In contrast with tissue from the proximal part and from controls, the distal samples revealed a marked reduction in the noradrenergic innervation of the muscle coat. In addition acetylcholinesterase-containing nerves associated with the basal aspect of the epithelium were usually absent from the distal portion of the vas deferens. These findings have been considered in relation to the contractile and secretory activities of the organ following vasovasostomy and may be of importance to the maturation and fertility of spermatozoa.

PIP: Vas deferens specimens taken from 43 men during vasovasostomy were examined by histochemical techniques and electron microscopy for evidence of noradrenergic and acetylcholinergic nerve structures. The subjects had been vasectomized 1-15 years ago (mean 6.5 years). Controls were 22 men being operated for vasectomy. Light microscopy revealed fine noradrenergic nerve plexi throughout the muscle coat, in the proximal, urethral portions of the vas, and circling blood vessels in the adventitia, as well as in both proximal and distal control specimens. The distal, testicular specimens of previously vasectomized men contained only occasional adrenergic fibers. In proximal or urethral portions, fine cholinergic nerves occurred in the muscle coat; large ones in the adventitia near blood vessels, and numerous cholinergic fibers were located under the epithelium. In distal, testicular portions, cholinergic nerves were similar to controls and to urethral specimens from vasectomized men in the muscle layer only, but absent in lamina propria. Ultramicroscopic structure of these various nerve fibers is described in detail. It is to be noted that the distal portion of the vas is the testicular portion, as concerns innervation, and this is lost after vasectomy. It was remarkable to see evidence of reinnervation of cholinergic axons distally, however. It has been established that noradrenergic control is important for the motor and secretory activities of the vas. Physiological significance of adrenergic innervation is unknown. These results add evidence for the advice to men seeking vasectomy to consider it a permanent form of fertility control.

A comparison of diuresis renography, the Whitaker test and renal pelvic morphology in idiopathic hydronephrosis.

Diuresis renography and the Whitaker test are established methods of diagnosing obstruction in dilated renal pelves. These techniques have been compared in 36 patients with radiologically demonstrated idiopathic hydronephrosis and evaluated, where possible, against renal pelvic morphological features. The agreement between the results of the tests was as follows: diuresis renography/Whitaker test 67%; diuresis renography/renal pelvic morphology 74%; Whitaker test/renal pelvic morphology 58%. Both diuresis renography and the Whitaker test are indicated in some cases of idiopathic hydronephrosis.

Bladder outflow obstruction--a cause of denervation supersensitivity.

Eighteen Landrace pigs and 12 Göttingen mini-pigs were evaluated in a study of experimental bladder outflow obstruction. Twenty-two of the animals underwent partial bladder outflow obstruction for periods up to 12 months. The subsequent changes were assessed using cystometric, physiological and morphological means. There was a consistent increase in the voiding pressures and a concomitant reduction in the flow rates in all the obstructed animals. Seventy-seven per cent of the obstructed animals showed cystometric evidence of bladder instability. In vitro studies showed an increase in sensitivity to exogenously applied agonists and a reduction in sensitivity to intramural nerve stimulation. Morphological studies showed an inverse correlation between neuronal density and the duration of obstruction. These changes are typical of post-junctional supersensitivity secondary to partial denervation. These results suggest that agents capable of stabilising the bladder smooth muscle membrane may be useful in the treatment of detrusor instability secondary to bladder outflow obstruction.

Cystometric, physiological and morphological studies after relief of bladder outflow obstruction in the pig.

Experimental bladder outflow obstruction was relieved in 18 pigs between 2 and 15 months after the creation of partial urethral obstruction. Cystometric, physiological and morphological studies were performed 2 to 6 months after relief of the obstruction. An increase in average voiding flow rates from 2.8 +/- 1.0 ml/s to 6.8 +/- 1.2 ml/s was recorded in the Landrace pigs and from 2.2 +/- 0.9 ml/s to 7.4 +/- 1.4 ml/s in the Göttingen mini-pigs. There was a concomitant decrease in the voiding detrusor pressures from 52 +/- 11 cm H2O to 32 +/- 8 cm H2O and from 78 +/- 12 cm H2O to 33 +/- 6 cm H2O respectively. A return towards control values of the physiological responses to exogenously applied agonists (acetylcholine and potassium) and to electrical field stimulation was observed. There was an increase in neuronal innervation in the morphological studies which was more marked in the animals with a shorter period of obstruction. The implications for patient care are discussed.