Solvay (United States)

The Hypogonadism in Males study estimated the prevalence of hypogonadism [total testosterone (TT) < 300 ng/dl] in men aged > or = 45 years visiting primary care practices in the United States. A blood sample was obtained between 8 am and noon and assayed for TT, free testosterone (FT) and bioavailable testosterone (BAT). Common symptoms of hypogonadism, comorbid conditions, demographics and reason for visit were recorded. Of 2162 patients, 836 were hypogonadal, with 80 receiving testosterone. Crude prevalence rate of hypogonadism was 38.7%. Similar trends were observed for FT and BAT. Among men not receiving testosterone, 756 (36.3%) were hypogonadal; odds ratios for having hypogonadism were significantly higher in men with hypertension (1.84), hyperlipidaemia (1.47), diabetes (2.09), obesity (2.38), prostate disease (1.29) and asthma or chronic obstructive pulmonary disease (1.40) than in men without these conditions. The prevalence of hypogonadism was 38.7% in men aged > or = 45 years presenting to primary care offices.

Gold and silver nanoparticles, with different sizes, have been synthesized using ascorbic acid which allows a versatile and simple post-functionalisation.

OBJECTIVES: Pancreatic-enzyme replacement therapy (PERT) is the standard of care to prevent maldigestion, malnutrition, and excessive weight loss in patients with exocrine pancreatic insufficiency (EPI) due to chronic pancreatitis (CP) or pancreatic surgery (PS). Our objective was to assess the efficacy and safety of a new formulation of pancrelipase (pancreatin) delayed-release 12,000-lipase unit capsules (CREON) in patients with EPI due to CP or PS. METHODS: This was a double-blind, randomized, multicountry, placebo-controlled, parallel-group trial enrolling patients ≥18 years old with confirmed EPI due to CP or PS conducted in clinical research centers or hospitals. After a 5-day placebo run-in period (baseline), patients were randomized to pancrelipase (72,000 lipase units per meal; 36,000 per snack) or placebo for 7 days. All patients received an individually designed diet to provide at least 100 g of fat per day. The primary efficacy measure was the change in coefficient of fat absorption (CFA) from baseline to end of the double-blind period, analyzed using non-parametric analysis of covariance. Secondary outcomes included the coefficient of nitrogen absorption (CNA), clinical symptoms, and safety parameters. RESULTS: In total, 25 patients (median age of 54 years, 76% male) received pancrelipase and 29 patients (median age of 50 years, 69% male) received placebo. Th e mean ± s.d. change from baseline in CFA was significantly greater with pancrelipase vs. placebo: 31.9 ± 18.6 vs. 8.7 ± 12.4 % ( P < 0.0001) [corrected]. Similarly, the mean ± s.d. change from baseline in CNA was greater for pancrelipase vs. placebo: 35.2 ± 29.1 vs. 8.9 ± 28.0 % ( P = 0.0005) [corrected].Greater improvements from baseline in stool frequency, stool consistency, abdominal pain, and flatulence were observed with pancrelipase vs. placebo. Treatment-emergent adverse events (TEAEs) were reported in five patients (20.0%) in the pancrelipase group and in six (20.7%) in the placebo group; the most common were gastrointestinal (GI) events and metabolism/nutrition disorders. There were no treatment discontinuations due to TEAEs. CONCLUSIONS: Pancrelipase delayed-release 12,000-lipase unit capsules were effective in treating fat and nitrogen maldigestion with a TEAE rate similar to that of placebo in patients with EPI due to CP or PS.

Menopause is associated with decreased lean body mass and increased fat due to aging and declining hormone secretion. Estrogens or estrogen-progestins have been used to alleviate vasomotor symptoms. However, estrogen-androgen (E/A) therapy is also used for vasomotor symptom relief and has been shown to increase lean body mass while decreasing fat mass. The objective of this 16-wk, double-blind, randomized, parallel group clinical trial was to compare esterified estrogen plus methyltestosterone (1.25 mg estrogen + 2.5 mg methyltestosterone/d; E/A group) vs. esterified estrogen alone (1.25 mg/d; E group) on body composition. Forty postmenopausal women (mean age, 57 yr) participated. Compared with estrogen treatment alone, women in the E/A group increased their total lean body mass and reduced their percentage fat for all body parts (P < 0.05). After E/A treatment, there were statistically significant increases in lean body mass by 1.232 kg [0.181 +/- 0.004, 0.81 +/- 0.057, and 0.24 +/- 0.009 kg in the upper body (P = 0.021), trunk (P = 0.001), and lower body (P = 0.047), respectively]. In the E group, the increase was 0.31 +/- 0.004, 0.021 +/- 0.03, and 0.056 +/- 0.05 kg in the upper body, trunk, and lower body, respectively. In the E/A group, body fat was reduced by 0.90 kg (P = 0.18 for the trunk only), and percentage body fat declined by 7.4% (P < or = 0.05 for all body parts). Lower body strength increased by 23.1 kg (51 lb) in the E/A group vs. only 11 kg (24.25 lb) in the E group (P = 0.002 between groups). A statistically significant increase in weight (2.7 +/- 5.1 vs. 0.1 +/- 4.6 lb; P < 0.05) was observed in the E/A group compared with the E group. When subjects were given self-reporting questionnaires, more improvement was noted in sexual functioning and quality of life in the E/A group when compared with patients receiving E alone. There were no noteworthy side effects. In conclusion, E/A replacement therapy can improve body composition, lower-body muscle strength, quality of life, and sexual functioning in postmenopausal women.

We report the self-organization of microfluidic emulsions into anomalously homogeneous structures. Upon periodic driving confined emulsions undergo a first-order transition from a reversible to an irreversible dynamics. We evidence that this dynamical transition is accompanied by structural changes at all scales yielding macroscopic yet finite hyperuniform structures. Numerical simulations are performed to single out the very ingredients responsible for the suppression of density fluctuations. We show that, as opposed to equilibrium systems, the long-range nature of the hydrodynamic interactions are not required for the formation of hyperuniform patterns, thereby suggesting a robust relation between reversibility and hyperuniformity which should hold in a broad class of periodically driven materials.

The antimicrobial activity of citric acid (CA) is often evaluated without pH adjustment or control and its impact on micro-organisms is better understood in acidic conditions. However, the biocidal action of the fully ionized CA molecule, predominantly available at higher pH, has not been previously investigated. The objective of this study was to evaluate the antimicrobial effect of high (10%) and low (1%) concentrations of CA, each adjusted over a wide range of pH values (4·5, 6·5 and 9·5) relative to the controls exposed to corresponding pH levels alone (no CA). The viability and morphology of Escherichia coli and Klebsiella aerogenes were evaluated using a culture-based enumeration assay in parallel with direct SEM imaging. Overall, the highest membrane damage and loss in viability were achieved with 10% CA at pH 9·5, which yielded at least 4·6 log10 CFU per ml (P < 0·001) reductions in both organisms. Insight into the superior efficacy of CA at high pH is proposed based on zeta potential measurements which reveal a more negatively charged bacterial surface at higher pH. This pH-dependent increase in surface charge may have rendered the cells potentially more sensitive towards chelants such as CA3− that interact with membrane-stabilizing divalent metals.

t-Butyl alcohol (TBA) was administered in drinking water to F344/N rats and B6C3F1 mice for two years using 60 animals/dose/sex/species. Male rats received doses of 0, 1.25, 2.5, or 5 mg/ml and females received 0, 2.5, 5, or 10 mg/ml, resulting in average daily doses of approximately 85, 195, or 420 mg TBA/kg body weight for males and 175, 330, or 650 mg/kg for females. Ten rats per group were evaluated after 15 months. Male and female mice received doses of 0, 5, 10, or 20 mg/ml, resulting in average daily doses of approximately 535, 1,035, or 2,065 mg TBA/kg body weight for males and 510, 1,015, or 2,105 mg/kg for females. Survival was significantly reduced in male rats receiving 5 mg/ml, female rats receiving 10 mg/ml, and male mice receiving 20 mg/ml. Long-term exposure to TBA produced increased incidences of renal tubule adenoma and carcinoma in male rats; transitional epithelial hyperplasia of the kidney in male and female rats; follicular cell adenoma of the thyroid in female mice; and follicular cell hyperplasia of the thyroid and inflammation and hyperplasia of the urinary bladder in male and female mice. In addition, a slight increase in follicular cell adenoma or carcinoma of the thyroid (combined) in male mice may have been related to the administration of TBA.

Angioedema and cough are known side effects of angiotensin-converting enzyme (ACE) inhibitors. Angiotensin-converting enzyme is a potent inhibitor of kinase II, which facilitates the breakdown of bradykinin. An increase in bradykinin levels results in continued prostaglandin E2 synthesis, vasodilation, increased vascular permeability, and increased interstitial fluid. In contrast, the angiotensin II receptor blockers (ARBs) do not increase bradykinin levels. Angioedema as a complication of ACE inhibitor therapy is not widely recognized; this complication is even less recognized with second-line ARBs. We report angioedema associated with losartan (an ARB) in a patient who had experienced angioedema secondary to enalapril (an ACE inhibitor). Almost half of patients with ARB-associated angioedema also had developed angioedema while receiving ACE inhibitor therapy. Clinicians should exercise caution when using ARBs in patients with a history of angioedema secondary to ACE inhibitors.

The water/graphene interface has received considerable attention in the past decade due to its relevance in various potential applications including energy storage, sensing, desalination, and catalysis. Most of our knowledge about the interfacial water structure next to graphene stems from simulations, which use experimentally measured water contact angles (WCAs) on graphene (or graphite) to estimate the water-graphene interaction strength. However, the existence of a wide spectrum of reported WCAs on supported graphene and graphitic surfaces makes it difficult to interpret the water-graphene interactions. Here, we have used surface-sensitive infrared-visible sum frequency generation (SFG) spectroscopy to probe the interfacial water structure next to graphene supported on a sapphire substrate. In addition, the ice nucleation properties of graphene have been explored by performing in situ freezing experiments as graphitic surfaces are considered good ice nucleators. For graphene supported on sapphire, we observed a strong SFG peak associated with highly coordinated, ordered water next to graphene. Similar ordering was not detected next to bare sapphire, implying that the observed ordering of water molecules in the former case is a consequence of the presence of graphene. Our analysis indicates that graphene behaves like a hydrophobic (or negatively charged) surface, leading to enhanced ordering of water molecules. Although liquid water orders next to graphene, the ice formed is proton disordered. This research sheds light on water-graphene interactions relevant in optimizing the performance of graphene in various applications.

induced arterial diseaseAleutian disease and equine viral arteritis. Adv Cardiol 1 3 :1 81 -1 91 . 1 4 . Huntington PJ, Ellis PM, Forman AJ, Timoney P J: 1 990, Equine viral arteritis. Aust Vet J 67:429-43 1 . 1 5. Johnson B, Baldwin C, Timoney P, Ely R: 1 991 , Arteritis in equine fetuses aborted due to equine viral arteritis. Vet Pathol 2 8:2 48-2 50. 1 6, Jones TC, Doll ER, Bryans JT: 1 957, The lesions of equine viral arteritis. Cornell Vet 57:52 -68. 1 7. MacLachlan NJ: 1 994, The pathogenesis and immunology of bluetongue virus infection of ruminants. Comp Immunol Microbiol Infect Dis 1 7: 1 97-206. 1 8. McCollum WH, Prickett ME, Bryan JT: 1 971 , Temporal distribution of equine arteritis virus in respiratory mucosa, tissues and body fluids of horses infected by inhalation. Res Vet Sci 1 2 :459-464. 1 9. Meulenberg JJM, Hulst MM, de Meijer EJ, et al.: 1 994, Lelystad virus belongs to a new family, comprising lactate dehydrogenase-elevating virus, equine arteritis virus, and simian hemorrhagic fever virus. Arch Virol (Suppl) 9:441 -448. 20. Monreal L, Villatoro AJ, Hooghuis H, et al.: 1 995, Clinical features of the 1 992 outbreak of equine viral arteritis in Spain. Equine Vet J 2 7:301 -304. 2 1 . Plagemann PGW, Moennig V: 1 991 , Lactate dehydrogenase elevating virus, equine arteritis virus, and simian hemorrhagic fever virus: a new group of positive strand RNA viruses. Adv Virus Res 41 :99-1 92 . 2 2 . Reed LJ, Muench H: 1 938, A simple method of estimating fifty percent endpoints. Am J Hyg 27:493 -497. 2 3 . Timoney PJ, McCollum WH: 1 991 , Equine viral arteritis virus: current clinical and economic significance. Proc Am Assoc Equine Pract 36:403 -409. 24. Timoney PJ, McCollum WH: 1 993 , Equine viral arteritis. Vet Clin North Am Equine Pract 9:295-309. 25. Vaala WE, Hamir AN, Dubovi EJ, et al.: 1 992 , Fatal, congenitally acquired infection with equine arteritis virus in a neonatal Thoroughbred. Equine Vet J 2 4:1 55-1 58. 26. Wada R, Kondo T, Fukunaga Y, Kanemaru T: 1 994, Histopathological and immunofluorescent studies on the uterus of aborted mares experimentally infected with equine arteritis virus. J Equine Sci 5:41 -43 . 27. Wood JLN, Chimside ED, Mumford JA, Higgins AJ: 1 995, First recorded outbreak of equine viral arteritis in the United Kingdom. Vet Rec 1 36:381 -385. 28. Zaki SR, Greer PW, Coffield LM, et al.: 1 995, Hantavirus pulmonary syndrome. Am J Pathol 1 46:552 -579.

Green chemistry is being implemented in chemical manufacturing to advance sustainability. A scouting survey and recent industry-wide reports find that several green chemistry principles and related metrics are routinely being implemented in the chemical manufacturing sector. A cross-section of stakeholders surveyed agree that broader adoption of the principles of green chemistry can be promoted by collaboration among companies to identify best practices and define opportunities to increase green chemistry implementation in chemical manufacturing. Active collaborative efforts to improve implementation include identifying common attributes of effective process metrics, developing means of tracking sector-wide implementation, and defining industrial needs for translating promising green chemistry ideas into implementable, cost-effective, and low business risk technologies.

We experimentally characterize heterogeneous nonexponential relaxation in bidisperse supercooled colloidal liquids utilizing a recent concept called "softness" [Phys. Rev. Lett. 114, 108001 (2015)PRLTAO0031-900710.1103/PhysRevLett.114.108001]. Particle trajectory and structure data enable classification of particles into subgroups with different local environments and propensities to hop. We determine residence times t_{R} between particle hops and show that t_{R} derived from particles in the same softness subgroup are exponentially distributed. Using the mean residence time t[over ¯]_{R} for each softness subgroup, and a Kramers' reaction rate model, we estimate the activation energy barriers E_{b} for particle hops, and show that both t[over ¯]_{R} and E_{b} are monotonic functions of softness. Finally, we derive information about the combinations of large and small particle neighbors that determine particle softness, and we explicitly show that multiple exponential relaxation channels in the supercooled liquid give rise to its nonexponential behavior.

Mixing simple additives into poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) dispersions can greatly enhance the thermoelectric properties of the cast films with little manufacturing cost, but design rules for many of these additives have yet to emerge. We show that controlling stoichiometry in ionic liquid (I.L.) additives can decouple morphological and electronic modifications to PEDOT:PSS and enhance its power factor by over 2 orders of magnitude. Blending I.L. additives with a 1:1 stoichiometry between cationic imidazolium (Im+) derivatives and anionic bis(trifluoromethane)sulfonamide (TFSI–) groups into PEDOT:PSS dispersions raised the film conductivity to ∼1000 S/cm. The Seebeck coefficient, which gives insight into the electronic structure as well as thermoelectric performance, remained unchanged. This behavior mimics that of popular high-boiling solvent additives such as dimethyl sulfoxide and ethylene glycol, which restructure the film morphology to enhance carrier mobility. Blending I.L. additives with a 4:1 stoichiometry between Im+ and TFSI– groups raises the conductivity in a similar manner but also enhances the Seebeck coefficient. This selective Seebeck enhancement proceeds from the interaction of excess Im+ with anionic poly(styrenesulfonate) (PSS–) groups, similar to previous studies using inorganic salts, that results in a shift in charge carrier populations. Inorganic salts by themselves cannot raise the conductivity of PEDOT:PSS to appropriate values since they lack the solvent restructuring effect. These I.L. additives combine the effects of high-boiling solvents and diffuse ions, with the ability to tailor the Seebeck coefficient through ion stoichiometry.

Fluvoxamine CR has been reported effective in the short-term (12-wk) treatment of generalized social anxiety disorder (social phobia). Social anxiety disorder (SAD) is, however, a chronic disorder thought to require maintenance treatment. We report on data from the extension phase of a short-term study, in order to explore the efficacy and safety profile of fluvoxamine CR (100-300 mg/d) in the longer-term treatment of this disorder. Adult outpatients with generalized social anxiety disorder (GSAD) at 35 centres in Europe, South Africa, and USA were included in an acute phase study (12 wk). Subjects who demonstrated at least minimal improvement by endpoint (n=112), were offered participation in an extension phase, in which medication was continued for a further 12 wk under double-blind conditions. Efficacy was assessed using the Liebowitz Social Anxiety Disorder Scale (LSAS), the Clinical Global Impression Global Improvement score (CGI-I), the Clinical Global Impressions Severity of Illness score (CGI-S), and the Sheehan Disability Scale (SDS). Safety and tolerability assessments were also performed at regular intervals. Subjects treated with fluvoxamine CR had a numerically greater decrease in LSAS total scores than subjects treated with placebo at endpoint. Analysis of data from baseline (day 1) to endpoint (last observation carried forward) demonstrated that this difference tended towards significance, while severity of illness on the CGI-S and disability on the SDS were significantly lower in the fluvoxamine CR group than in the placebo group. The same trends were observed when only data from weeks 12-24 were included in the analysis; although the magnitude of changes was smaller in the extension phase than in the acute phase, fluvoxamine CR-treated subjects continued to show improvement compared to placebo-treated subjects. Most treatment-emergent signs and symptoms (TESS) were mild to moderate in severity. No unexpected abnormalities were reported on vital signs, electrocardiagrams, or laboratory investigations. These data support the long-term efficacy, safety, and tolerability of fluvoxamine CR in the treatment of GSAD. Given the prevalence, persistence, and disability associated with GSAD, and the relative paucity of long-term treatment studies of SAD, the current dataset provides empirical support for the current clinical consensus that pharmacotherapy of this disorder should be continued beyond the acute phase.

OBJECTIVE: Patients with progressive relapsing (PR) multiple sclerosis (MS) may accrue disability by incomplete recovery from acute exacerbations and by ongoing deterioration. In primary progressive (PP) MS, disability accumulates solely by continuous decline. Because it is the least common form of MS, there is scant information regarding the clinical characteristics of PRMS, but relapses are reportedly uncommon. The purpose of this study is to describe the clinical features of a cohort of patients with PRMS. METHODS: A retrospective chart review of 16 patients diagnosed with PRMS at two academic MS centres over a four-year period. RESULTS: Nine men and seven women had PRMS. The mean age at onset was 35.1+/-11.2 years. The most common presenting symptom was a progressive myelopathy. The mean disease duration was 10.1+/-8.5 years and the average time to first exacerbation was 4.1+/-3.7years. Patients had an average of 2.8+/-2.3 relapses with an annualized relapse rate of 0.6+/-0.8. Time to Expanded Disability Status Scale (EDSS) 6.0 was strongly associated with time to first exacerbation. Although there was no correlation between the number of relapses and time to EDSS 6.0, there was a modest inverse relation between time to EDSS 6.0 and annualized relapse rate. CONCLUSIONS: Relapses in PRMS may occur more often than previously described and disability may accumulate more rapidly in PRMS than in PPMS. We suggest differentiating between these two forms of MS.

PURPOSE: The purpose of this article is to describe androgen deficiency in men, the consequences of this clinically underdiagnosed endocrine disorder, and its relationship to the metabolic syndrome and the association with type 2 diabetes. An overview of prevalence, screening, diagnosis, treatment, and monitoring of male hypogonadism is presented. Method Established guidelines were used to provide definition, diagnosis, treatment, and monitoring information for male hypogonadism. A literature review from 1990 to 2007 revealed study findings that identify the link between low testosterone in men and the development of type 2 diabetes. The following databases were used to review and analyze the current literature: CINAHL, PubMed, and MEDLINE. RESULTS: An analysis of 26 studies was completed. The key findings in all of these studies show that there is a link between low levels of testosterone and an adverse metabolic profile (ie, obesity and insulin resistance). There is evidence that hypogonadism is associated with metabolic syndrome and type 2 diabetes in men. CONCLUSION: Male hypogonadism is a clinical condition that affects a significant number of men in the United States and can affect up to 50% of men diagnosed with type 2 diabetes. The implications for diabetes educators are two-fold: first, there is a high prevalence of low testosterone in men with type 2 diabetes, and second, educators need to have a better understanding of this disease state to provide instructional guidance for their patients and to coordinate care with other clinicians.

STUDY OBJECTIVE: To evaluate the pharmacokinetics of haloperidol after intranasal administration compared with intravenous and intramuscular administration, and to evaluate systemic and local tolerance of intranasal administration. DESIGN: Randomized, open-label, three-way crossover study. SETTING: Academic medical center. SUBJECTS: Four healthy volunteers (two men, two women; aged 24-37 yrs). INTERVENTION: Each subject received in a randomized order the following three treatments, with a 2-week washout period between treatments: intravenous haloperidol 2.5 mg (0.5 ml of 5.0 mg/ml) infused over 15 minutes, intramuscular haloperidol 2.5 mg (0.5 ml of 5.0 mg/ml), and intranasal haloperidol 2.5 mg (2.5 mg/0.1-ml spray into a single naris). MEASUREMENTS AND MAIN RESULTS: Blood samples were obtained serially and plasma levels determined. Noncompartmental analysis was used to estimate pharmacokinetic parameters. Physical and nasal examinations and adverse-effect profiles were obtained to assess tolerance. Mean (percent coefficient of variation) haloperidol bioavailability after intranasal administration was 63.8% (24.4%) compared with intravenous administration and 48.6% (29.4%) compared with intramuscular administration. Intranasal administration achieved higher peak levels that occurred more quickly compared with intramuscular administration. Median time to maximum concentration was 15 minutes after the intranasal dose compared with 37.5 and 15 minutes after the intramuscular and intravenous doses, respectively. Subjects had mild-to-moderate systemic adverse effects, all related to an extension of haloperidol's pharmacologic actions. Two of the four subjects complained of mild-tomoderate nasal irritation after the intranasal doses. CONCLUSION: Our results suggest that additional research studies are warranted for further evaluation of intranasal administration of haloperidol. The product provides rapid therapeutic plasma levels and sedation, with only minor and short-lived nasal irritation. These data suggest that intranasal administration of haloperidol, or other antipsychotics with similar potency, could play a role in treating psychiatric emergencies.

Fluvoxamine, a selective serotonin reuptake inhibitor, was studied extensively in 34,587 predominantly depressed patients in 66 studies conducted world-wide. These studies were largely uncontrolled trials representing the use of fluvoxamine by psychiatric and general practice physicians in everyday conditions. The safety data were analyzed according to standardized medical review and data management policies. Approximately 70% of the fluvoxamine population were female and 44% were aged 31-51 years. The modal total daily dose was 100 mg. Safety findings revealed a pharmacological adverse event profile similar to that seen with other serotonin reuptake inhibitors. Nausea was found to be the only common symptom, with an incidence rate of 16%. Approximately 2% of the fluvoxamine population reported at least one serious adverse event (per FDA criteria). Overall suicidality rates of fluvoxamine were found to be low (0.7%). No cases of zimelidine syndrome, bleeding syndrome or Guillain-Barré syndrome were identified. Overall, fluvoxamine was found to be safe and well tolerated suggesting a favorable alternative in the treatment of depression.

A panel of experts formulated relevant domains of sexual function with a focus on sexual interest and desire. The resulting 10-item scale, the Menopausal Sexual Interest Questionnaire (MSIQ), was examined for reliability (internal consistency and test-retest repeatability), construct validity (concurrent, convergent, and discriminant), sensitivity, and specificity in a clinical trial. A principal components analysis identified three factors (desire, responsiveness, and satisfaction) with eigenvalues > 1. A high degree of internal consistency was observed for each of the three domains. Test-retest repeatability correlation coefficients for domain scores were all highly significant. The MSIQ demonstrated adequate construct validity, with all three domains showing a high degree of sensitivity and with two of the three exhibiting specificity to the effects of treatment.

To compare the retention force of individual clasps made from cobalt chromium (CoCr) or new aryl ketone polymer (AKP) material, Ultaire™ AKP, following prolonged fatigue testing along ideal and non-ideal paths of removal and to assess 3D deformation of the active and passive clasp tips. CoCr and AKP clasps were manufactured in their standard, respective processes, digitally scanned prior to testing, then cycled 15,000 times over an e.max analogue crown in artificial saliva. Retentive load was measured in situ, as a function of cycles. Clasps were rescanned to assess deformation and along with their antagonists subjected to SEM to assess localised wear. Distortion of the CoCr clasps was consistently larger than Ultaire™ AKP clasps, irrespective of removal path. CoCr clasps had significantly higher retentive forces than AKP clasps, for both removal paths. Ultaire™ AKP clasps showed a lower but relatively constant retentive force. The non-ideal path of removal affected retentive forces for both clasp materials. SEM showed localised removal of glaze for e.max crowns used with CoCr clasps. Ultaire™ AKP clasps showed significantly less permanent deformation and lower retentive force than CoCr clasps. Unlike CoCr, the Ultaire™ AKP clasps did not work harden, nor had as large a reduction in retentive force and accompanying permanent deformation; the retentive force for the Ultaire™ AKP clasps was consistent over 15,000 cycles of fatigue mimicking prolonged clinical use. The AKP material was more robust; showing minimal deformation even in non-ideal paths of removal, as many patients would routinely use.