ABSTRACT
INTRODUCTION: The stratum corneum is the biggest obstacle in cosmetics with respect to skin moisturisation. Many approaches have been taken to overcome the barrier, one of which is incorporating natural cosmeceuticals into cosmetic products to enhance moisturisation effects. Here, a commercial facemask formulation was electrospun to develop dry facemasks capable of hosting cosmeceuticals within the pores of incorporated mesoporous silica. METHODS: Ethanolic solutions containing 40% w/w of the marketed facemask (7th Heaven Dead Sea peel-off facemask) and mesoporous silica were prepared and electrically processed at 30 µL min-1 at an applied voltage of 12 ± 2 kV. In vitro characterisation and release studies using fluorescein dye as a model probe were carried out. RESULTS: SEM images confirmed the fibrous nature of the resulting matrix; showing an average fiber diameter of 298.32 nm. The electrospun mask was found to be advantageous due to this fibrous nature providing high active loading capacity whilst demonstrating 100% probe release within 60 min. Contact Angle hysteresis, thermal analysis and Fourier Transform Infrared Spectroscopy (FTIR) presented evidence of compatibility and stability of and within the formulation. CONCLUSION: Adapting the formulation of a commercial polymeric facemask into an electrospun facemask has shown the versatility of the electrospinning process; now successfully crossing over into the cosmetic industry.
INTRODUCTION: La couche cornée est le premier obstacle à l'hydratation de la peau par des produits cosmétiques. De nombreuses approches ont été adoptées pour surmonter cette entrave, dont l'une consiste à intégrer des cosméceutiques naturels dans les produits cosmétiques afin d'augmenter leur pouvoir hydratant. Ici, la formulation commercialisée d'un masque pour le visage a été modifiée par électrofilage de manière à développer des masques secs pouvant intégrer des cosméceutiques dans les pores de silice mésoporeuse présent dans le produit. MÉTHODES: Des solutions éthanoliques, contenant 40 % p/p du masque pour le visage commercialisé (masque peel-off 7th Heaven Dead Sea) et de la silice mésoporeuse ont été préparées et traitées électriquement à 30 µl/min_ 1, avec une tension appliquée de 12 ± 2 kV. Des études de caractérisation et de libération in vitro ont été menées, utilisant un colorant fluorescéine en tant que sonde. RÉSULTATS: Des images SEM ont confirmé la nature fibreuse de la matrice résultante, avec un diamètre de fibre moyen s'élevant à 298,32 nm. Le masque électrofilé a été jugé avantageux en raison de sa nature fibreuse, qui permet une capacité de charge élevée, ainsi qu'une libération de 100 % de la sonde dans les 60 min. L'hystérèse de l'angle de contact, l'analyse thermique et la spectroscopie infrarouge à transformée de Fourier (IRTF) ont permis d'identifier des preuves de compatibilité et de stabilité dans cette formulation. CONCLUSION: La possibilité d'adapter la formulation d'un masque pour le visage polymérique déjà commercialisé pour en faire un masque électrofilé montre la polyvalence du processus d'électrofilage, qui fait une apparition remarquable dans le domaine des cosmétiques.
Subject(s)
Cosmetics , Silicon Dioxide/chemistry , Skin/metabolism , Water/metabolism , Calorimetry, Differential Scanning , Fluorescein/chemistry , Humans , Microscopy, Electron, Scanning , Spectroscopy, Fourier Transform InfraredABSTRACT
OBJECTIVE: To assess the level of modification by local primary care doctors of key aspects of the National Asthma Education Program (NAEP) Guidelines for the Diagnosis and Management of Asthma. DESIGN: A random sample of primary care physicians participating in local asthma guideline development. SETTING: Two hospital systems, one based in an urban environment, and a second in a community and rural environment. PARTICIPANTS: Primary care physicians. INTERVENTION: Design of consensus-based local asthma guidelines using a modified Delphi approach. MEASUREMENTS AND MAIN RESULTS: A total of 42 physicians participated in the local guideline development. With few exceptions, the primary care physicians modified in major ways the NAEP Guidelines regarding the role of pulmonary function testing and spirometry. Specifically, the local guidelines did not require peak flow and spirometry measurements as the basis for initiating inhaled steroids as did the national guidelines. All 42 physicians emphasized a clinical diagnosis versus one based on a pulmonary function. Peak flow monitoring was recommended by 35 (83%) of physicians in selected patients only, in contrast to the national guidelines, which emphasized monitoring for all patients routinely and during exacerbations. There was strong agreement with the national guidelines on the role and importance of patient education, and on the indications for the use of inhaled steroids. CONCLUSIONS: Disagreement by primary care doctors with parts of the NAEP guideline is a potential cause for poor compliance and lack of influence on patient care. Recognizing the need to modify or customize guidelines through field testing with local primary care physicians will improve acceptance of national guidelines.
Subject(s)
Asthma/diagnosis , Asthma/drug therapy , Practice Guidelines as Topic/standards , Primary Health Care/standards , Administration, Inhalation , Adrenal Cortex Hormones/administration & dosage , Data Collection , Female , Guideline Adherence , Humans , Male , Massachusetts , Practice Patterns, Physicians' , Referral and Consultation/standards , Respiratory Function Tests , Rural Population , Urban PopulationABSTRACT
The relationship of insurance type to treatment-seeking behavior (ie, the transportation to emergency departments of patients with symptoms suggestive of acute cardiac ischemia) was evaluated. The focus was on comparing patients belonging to a health maintenance organization (HMO) with patients who had indemnity insurance. Data were collected prospectively on 10,783 patients presenting to emergency departments of 10 adult care hospitals in the Eastern and Midwestern United States between April and December 1993 as part of a clinical trial. A total of 6,604 patients presented within 24 hours of symptom onset. Although these patients as a group had a wide range of demographic and clinical characteristics, persons belonging to an HMO and those with indemnity insurance were very similar. The main outcome measures were whether the patient was transported by ambulance and the duration of time from symptom onset to emergency department arrival. A hospital-matched sample of HMO-insured and indemnity-insured patients allowed multivariable regression: HMO membership was not associated with a different rate of ambulance use (odds ratio = 1.0; 95% confidence interval = 0.73, 1.35) or duration of time from symptom onset to emergency department presentation (6 minutes less, P = 0.8). HMO participation was not related to treatment-seeking behavior, as reflected by ambulance use and duration of time from symptom onset to emergency department arrival. However, studies of more constrained managed care organizations and of broader ranges of patients are needed.
Subject(s)
Ambulances/statistics & numerical data , Emergency Service, Hospital/statistics & numerical data , Health Maintenance Organizations/statistics & numerical data , Insurance, Health/statistics & numerical data , Myocardial Ischemia/economics , Adult , Aged , Data Collection , Demography , Emergency Service, Hospital/economics , Female , Humans , Insurance Coverage , Male , Middle Aged , Multivariate Analysis , Patient Acceptance of Health Care/statistics & numerical data , Prospective Studies , Time Factors , United StatesABSTRACT
Physicians' attitudes toward capitated payment have not been quantified. We sought to assess physicians' views on capitated payment and to compare the views of those who did and did not participate in such payment. A written survey was given to 200 physicians with admitting privileges at a 600-bed Ohio hospital; 82 (41%) responded and were included in this study. Among respondents, 21 (26%) were primary care physicians, 18 (22%) were medical subspecialists, and 18 (22%) were surgeons. Fifty-eight (71%) were providers for managed care plans, and 35 (43%) participated in capitated payment arrangements. Among physicians who did not participate in capitated care, 100% believed that there was a conflict of interest in capitated payment, and 77% (23 physicians) believed that participation in plans that reduce physician income in proportion to medical expenditures is not acceptable. Among those who did participate in capitated payment contracts, 95% (41 physicians) believed these plans posed a conflict of interest, and 72% (31 physicians) said this was not acceptable (P = 0.4 and 0.66 for each comparison). There was no trend toward the opinion that capitated payment arrangements are acceptable with greater levels of experience in capitated care (P = 0.5 by Spearman test). There were trends suggesting that compared with those who were not receiving capitated payments, those who received capitated payment were 50% more likely to have never discussed capitated payment with any patient (63% versus 42%, P = 0.08), were 70% more likely to very strongly oppose the use of capitation to pay their own family's physicians (49% versus 29%, P = 0.07), and were 30% more likely to believe that it is impossible to stay in the practice of medicine without participating in capitated payment plans (84% versus 65%, P = 0.06). None of the respondents reported that they had a contractual "gag clause," but 34% (27 physicians) said they would not speak publicly about any perceived risks of capitated payments anyway. Among this sample of physicians, those who participated in existing capitated payment managed care plans had views that were as negative, or more negative, on the acceptability of capitated payment as did those of nonparticipating physicians. Many were participating in capitated payment plans in spite of these negative views because they feared that to do otherwise would force them out of medical practice. The hypotheses generated by this study must be tested in larger, national studies.
Subject(s)
Attitude of Health Personnel , Capitation Fee/statistics & numerical data , Physicians/psychology , Data Collection , Health Knowledge, Attitudes, Practice , Health Services Research , Hospital Bed Capacity, 500 and over , Hospitals, Teaching , Humans , Medical Staff Privileges , Ohio , Physicians/statistics & numerical dataABSTRACT
Nitric oxide mediates nerve-induced hyperpolarization of circular smooth muscle of the esophagus. Two mechanisms are proposed to explain this hyperpolarization: an increase in K+ current or a decrease in Cl- current. These studies test the hypothesis that nitric oxide increases a K+ current in esophageal smooth muscle. Three outward K+ currents are present in circular smooth muscle cells from the opossum esophagus. One current is a Ca(2+)-activated K+ current (IKCa2+). This current is inhibited by charybdotoxin. Whole cell currents were recorded from isolated opossum esophageal smooth muscle cells using the whole cell patch-clamp technique. These studies showed that IKCa2+ is activated at potentials more positive than -30 mV. Bath application of S-nitroso-L-cysteine increased IKCa2+ by 50% above control levels throughout the entire activation range of potentials. The enhanced current was reversible on washout. Either charybdotoxin, an inhibitor of IKCa2+, or (R)-p-8-(4-chloropenylthio)-guanosine 3',5'-cyclic monophosphorothioate, an inhibitor of protein kinase G, antagonized the increase in outward current induced by S-nitroso-L-cysteine. These data suggest that nitric oxide activates IKCa2+ via the guanosine 3',5'-cyclic monophosphate-protein kinase G signal transduction pathway.
Subject(s)
Calcium/physiology , Esophagus/physiology , Muscle, Smooth/physiology , Nitric Oxide/physiology , Potassium/physiology , S-Nitrosothiols , Animals , Charybdotoxin/pharmacology , Cyclic GMP/analogs & derivatives , Cyclic GMP/pharmacology , Cysteine/analogs & derivatives , Cysteine/pharmacology , Electric Conductivity , Electrophysiology , Esophagus/cytology , Esophagus/drug effects , Female , Male , Muscle, Smooth/cytology , Muscle, Smooth/drug effects , Nitric Oxide/pharmacology , Opossums , Thionucleotides/pharmacologyABSTRACT
Chemically altered hemoglobins are being investigated as blood substitutes. They may affect numerous biological processes since free hemoglobin binds nitric oxide (NO). Nitric oxide is a neural mediator of relaxation of the lower esophageal sphincter (LES) and esophageal peristalsis. We hypothesize that recombinant human hemoglobin (rHb1.1) alters esophageal motor function by scavenging NO. Contraction of transverse muscle strips from the opossum esophagus and LES was monitored. Transmembrane potential differences of circular smooth muscle from the esophagus were recorded using glass microelectrodes. Intrinsic esophageal nerves were stimulated electrically. Esophageal manometries were performed with a low-compliance perfused-catheter system. The activity of the enzyme NO synthase was determined with the citrulline assay. Recombinant hemoglobin diminished nerve-induced relaxation of LES muscle but did not alter LES tone. Circular esophageal muscle responded to nerve stimulation with an inhibitory junction potential and a mechanical off response. Recombinant hemoglobin diminished the inhibitory junction potential and shortened the latency of the off response. It increased the velocity of esophageal peristalsis, decreased the amplitudes of these contractions and diminished LES relaxation. Cyanomethemoglobin had little effect on nerve- or swallow-induced responses. Hemoglobin did not inhibit the activity of NO synthase. Recombinant human hemoglobin appears to alter esophageal motor function by scavenging NO.