Dynamic symmetry-breaking in a simple quantum model of magneto-electric rectification, optical magnetization, and harmonic generation.

The state mixings necessary to mediate three new optical nonlinearities are shown to arise simultaneously and automatically in a 2-level atom with an ℓ = 0 ground state and an ℓ = 1 excited state that undergoes a sequence of electric and magnetic dipole-allowed transitions. The treatment is based on an extension of dressed state theory that includes quantized electric and magnetic field interactions. Magneto-electric rectification, transverse magnetization, and second-harmonic generation are shown to constitute a family of nonlinear effects that can take place regardless of whether inversion is a symmetry of the initial unperturbed system or not. Interactions driven jointly by the optical electric and magnetic fields produce dynamic symmetry-breaking that accounts for the frequency, the intensity dependence, and the polarization of induced magnetization in prior experiments. This strong field quantum model explains not only how a driven 2-level system may develop nonlinear dipole moments that are forbidden between or within its stationary states, but it also broadens the class of materials suitable for optical energy conversion applications and magnetic field generation with light so as to include all transparent dielectrics.

Elevated serum cardiac troponin I in older patients with hip fracture: incidence and prognostic significance.

INTRODUCTION: Cardiovascular complications are the main causes of morbidity and mortality in patients with osteoporotic hip fracture (HF). The aim of this prospective study was to evaluate the incidence and prognostic significance of elevated cardiac troponin I (cTnI) in the early peri-operative period in older patients with HF. MATERIALS AND METHODS: A blind evaluation of myocardial injury as detected by cTnI elevation in 238 consecutive older patients with low-trauma HF (mean age 81.9 +/- 7.8 (SD) years; 72% females). Data on demographic and clinical characteristics, in-hospital mortality, hospital length of stay and discharge destination were collected prospectively. Serum cTnI level was analysed from blood collected routinely in the first 72 h of hospital admission. RESULTS: Sixty-nine (29%) patients had elevated cTnI (>0.06 microg/l) but myocardial injury was clinically recognised in only 23 (33%) and only 24 (34.8%) had a history of coronary artery disease (CAD). Patients with elevated cTnI were significantly older, more often had American Society of Anaesthesiologist status score >or=3, a history of CAD or stroke and more often were current smokers than the patients without cTnI elevation. In multivariate regression analysis only age was an independent predictor of cTnI elevation. Patients with cTnI release were twice as likely to have a length of stay >or=20 days (P = 0.047) and 2.7 times more likely to be discharged to a long-term residential care facility (RCF) (P = 0.013). cTnI level >or=1 microg/l was a strong independent predictor of all-cause mortality with 98.3% specificity and 89.1% negative predictive value. CONCLUSION: Peri-operative myocardial injury is common in older HF patients but is frequently unrecognised clinically. Elevated blood cTnI level is an independent predictor of prolonged length of hospital stay (>or=20 days), need for long-term RCF and mortality (if cTnI >or=1 microg/l).

Molecular cloning and characterization of the constitutive bovine aortic endothelial cell nitric oxide synthase.

The constitutive endothelial cell nitric oxide synthase (NOS) importantly regulates vascular homeostasis. To gain understanding of this enzyme, a pEF BOS cDNA library of 5 x 10(5) clones was prepared from bovine aortic endothelial cells (BAEC) and screened with a 2.8-kb cDNA BamHI fragment of rat brain NOS. Clone pBOS13 was found to express NO synthase activity when transfected into COS-7 cells. Sequence analysis revealed sequences compatible with binding domains for calcium/calmodulin, flavin mononucleotide, flavin adenine nucleotide and NADPH. The deduced amino acid sequence revealed a protein with a relative mol mass of 133,286, which is 58% homologous to the rat cerebellar NOS and 51% homologous to the mouse macrophage NOS. The amino-terminal portion of the protein exhibits several characteristics peculiar to the endothelial cell NOS. These include a proline-rich region and several potential sites for proline-directed phosphorylation as well as a potential substrate site for acyl transferase. Northern hybridization to mRNA from cultured BAEC revealed an abundant 4.8-kb message, which was not increased by coincubation with tumor necrosis factor alpha, but was markedly increased by exposure to shear stress for 24 h. The unique features of the endothelial cell NO synthase, particularly in the amino terminal portion of the molecule, may provide for novel regulatory influences of enzyme activity and localization.

Outcomes for older patients with hip fractures: the impact of orthopedic and geriatric medicine cocare.

OBJECTIVES: To assess the impact of a specifically designed model of orthopedic-geriatric cocare on hip fracture (HF) outcomes. SETTING: Tertiary teaching hospital (level I trauma center). DESIGN: Prospective observational study with a retrospective (historical) control. Data on 951 consecutive patients 60 years of age or older admitted to the authors' institution with a nonpathologic HF over a 7-year period (1995 to 2002) were analyzed. Between 1995 and 1997, medical problems were managed by a geriatric medicine (GM) consultation-only service (retrospective audit). In 1998, a GM registrar began overseeing daily medical care with weekly geriatrician consultant review (prospective study). Outcomes for 2 time periods were compared: a 3-year period before (no GM; 504 patients) and a 4-year period after (GM; 447 patients) the introduction of GM cocare. MAIN OUTCOME MEASUREMENTS: Postoperative medical complications, mortality, length of stay, discharge destination, use of thromboprophylaxis, and antiosteoporotic treatment. RESULTS: While comparing 2 periods (GM and no GM), significant reductions in postoperative medical complications and comorbid conditions (in total 49.5% vs. 71.0%, P<0.001) and mortality (4.7% vs. 7.7%, P<0.01) occurred and rehospitalization to medical wards within 6 months decreased (28% vs. 7.6%). However, no differences were observed in median length of hospital stay (10.8 vs. 11.0 days) or in discharge destination. Antiosteoporotic treatment (12% to 69%) and specific thromboprophylaxis (63% to 94%) increased in the GM period. CONCLUSIONS: Orthopedic-geriatric cocare for the older patients with HF was associated with significant reductions in morbidity and mortality, and increases in optimal postoperative care. Options for further improvement of orthopedic-GM cocare need to be investigated.

Charge-tunnelling and self-trapping: common origins for blinking, grey-state emission and photoluminescence enhancement in semiconductor quantum dots.

Understanding instabilities in the photoluminescence (PL) from light emitting materials is crucial to optimizing their performance for different applications. Semiconductor quantum dots (QDs) offer bright, size tunable emission, properties that are now being exploited in a broad range of developing technologies from displays and solar cells to biomaging and optical storage. However, instabilities such as photoluminescence intermittency, enhancement and bleaching of emission in these materials can be detrimental to their utility. Here, we report dielectric dependent blinking, intensity-"spikes" and low-level, "grey"-state emission, as well as PL enhancement in ZnS capped CdSe QDs; observations that we found consistent with a charge-tunnelling and self-trapping (CTST) description of exciton-dynamics on the QD-host system. In particular, modulation of PL in grey-states and PL enhancement are found to have a common origin in the equilibrium between exciton charge carrier core and surface-states within the CTST framework. Parameterized in terms of size and electrostatic properties of the QD and its nanoenvironment, the CTST offers predictive insight into exciton-dynamics in these nanomaterials.

Correction: Charge-tunnelling and self-trapping: common origins for blinking, grey-state emission and photoluminescence enhancement in semiconductor quantum dots.

Correction for 'Charge-tunnelling and self-trapping: common origins for blinking, grey-state emission and photoluminescence enhancement in semiconductor quantum dots' by M. A. Osborne, et al., Nanoscale, 2016, 8, 9272-9283.

A carboxy-terminal deletion mutant of protein kinase C beta II inhibits insulin-stimulated 2-deoxyglucose uptake in L6 rat skeletal muscle cells.

Alternative splicing of pre-mRNA encoding the carboxy-terminal (C-terminal) exons of protein kinase C beta (PKC beta) leads to the expression of two protein isoforms, PKC beta 1 and PKC beta II, with the potential for different functions. PKC beta II expression is regulated by insulin via alternative mRNA splicing. A physiological consequence of its activation was investigated in L6 rat skeletal muscle cells expressing GLUT4 transporters, a cell line in which PKC is involved in glucose transport. We examined the contribution of PKC beta II for insulin-stimulated [3H]2-deoxyglucose uptake by constructing three PKC beta II C-terminal deletion mutants designated M216, M217, and M218. When transiently expressed in COS1 cells, M217, with nine amino acids deleted, demonstrated autophosphorylation activity 10-fold less than full-length PKC beta II. The mutants M218, with 13 amino acids deleted, and M216, with 52 amino acids deleted, demonstrated no autophosphorylation activity and are kinase negative. When transiently expressed in L6 myotubes, M217 inhibited insulin-stimulated 2-deoxyglucose uptake by 45% (with a 45% transfection efficiency) whereas M216 and M218, kinase-negative mutants, had no effect compared with cells transfected with control plasmid. Cotransfection of full-length PKC beta II with M217 was able to rescue the inhibition of insulin-stimulated 2-deoxyglucose uptake as compared with cotransfection of M217 with the control plasmid, suggesting that M217 acts as a dominant-negative. In contrast, cotransfection of full-length PKC beta I, the other alternatively spliced form, did not rescue inhibition of insulin-stimulated 2-deoxyglucose uptake by M217. To further demonstrate the involvement of PKC, specifically PKC beta II, in insulin-stimulated 2-deoxyglucose uptake, we used two inhibitors, CG41251 (a specific PKC inhibitor) and CG53353 (a PKC beta II-specific inhibitor at 1 microM). Both inhibited insulin-stimulated 2-deoxyglucose uptake 50-60% in L6 myotubes. We conclude that M217 may act as a specific PKC beta II dominant-negative and that PKC beta II is more specific for insulin-stimulated 2-deoxyglucose uptake in these cells than PKC beta I.

Nephrotoxicity and hepatotoxicity of histamine H2 receptor antagonists.

The extensive use of selective histamine H2 receptor antagonists provides a unique opportunity to describe very rare adverse drug reactions. Although mild elevation of serum creatinine level following the administration of cimetidine is relatively common, acute interstitial nephritis (AIN) is a rare hypersensitivity reaction. There have been 25 published reports of AIN associated with H2 antagonist therapy and we also identified 16 cases from the Australian Adverse Drug Reaction Advisory Committee (ADRAC) database. AIN was reported most commonly following cimetidine administration. AIN was supported by renal biopsy in 28 patients and by rechallenge in 6. H2 antagonist-induced AIN was more commonly reported in men older than 50 years. In the majority of cases the onset was within 2 weeks of initiation of therapy (1 day to 11 months). The clinical manifestations were nonspecific including sterile pyuria, elevated erythrocyte sedimentation rate, fatigue, proteinuria and leucocytosis whereas rash, arthralgia and flank pain were rarely reported. There were 170 cases of hepatotoxicity following H2 antagonist administration reported to ADRAC. These were more common following ranitidine and included cholestatic, hepatocellular and mixed reactions. Hepatotoxicity was proven following liver biopsy in several cases published in the literature and in 15 cases reported to ADRAC. Hepatotoxicity recurred upon rechallenge in 6 cases. Generally, renal and hepatic adverse effects resolved quickly after cessation of H2 antagonist therapy and did not require specific treatment. Nephrotoxicity and hepatotoxicity following administration of an H2 antagonist is rare and a high index of suspicion is necessary for early detection. Now that many H2 antagonists are available over the counter, awareness of these conditions and early detection with cessation of H2 antagonist therapy would appear paramount.

Persulfate hair bleach reactions. Cutaneous and respiratory manifestations.

Ammonium persulfate is widely used to "boost" peroxide hair bleaches. These persulfates can produce a variety of cutaneous and respiratory responses, including allergic eczematous contact dermatitis, irritant dermatitis, localized edema, generalized urticaria, rhinitis, asthma, and syncope. Some of these reactions appear to be truly allergic while others appear to be due to the release of histamine on a nonallergic basis. Patch tests may be performed with 2% to 5% aqueous solution of ammonium persulfate. Scratch tests may result in asthma and syncope. In some patients, merely rubbing a saturated solution of ammonium persulfate into the skin will evoke a large urticarial wheal. Hairdressers should be made aware that these ammonium persulfate hair bleach preparations may provoke severe reactions and should seek medical attention if the client complains of severe itching, tingling, a burning sensation, hives, dizziness, or weakness.

Contact stomatitis.

Allergic contact stomatitis may be difficult to distinguish from irritant stomatitis and may mimic the oral changes of a vitamin deficiency, certain anemias, uremic stomatitis, stomatitis nicotina, and even candidiasis. When these conditions have been ruled out, skin patch testing may be indicated. There is no need to test the oral mucosa directly because the oral mucosa and skin are sensitized at the same time.

Clinical pathway for pediatric parenteral nutrition.

The nutrition support team at Lucile Salter Packard Children's Hospital at Stanford developed a clinical pathway for infants and children receiving parenteral nutrition (PN). Use of clinical pathways for health care delivery is one way in which clinicians and institutions are responding to pressure from managed care organizations to reduce costs and maintain or improve quality. This pathway was developed to standardize the process for ordering, implementing, and monitoring PN. Specific goals for the pathway are as follows: to decrease the number of patients receiving PN inappropriately, to decrease the duration of PN for those patients who require it, to determine complication rates, and to monitor outcomes of therapy. Such comprehensive monitoring will help identify areas for improvement. By developing and implementing action plans to address these issues, we expect to improve continuously the processes and outcomes associated with PN therapy.

A "current contact news" follow-up: controversial subjects and those resulting in litigation.

PIP: In May 1993, the US Food and Drug Administration (FDA) granted product approval for the first female condom made of polyurethane. It provides some protection against sexually transmitted diseases (STDs), but the data are limited on the effectiveness of the Reality Vaginal Pouch against STDs. Female condom users have a relatively high pregnancy rate. FDA requires the label for Reality to stress that latex condoms for men are most effective against STDs and HIV/AIDS. Men who are sensitive to rubber can use condoms made of sheep intestine or cecum (brand names: Fourex and Lambskin). These nonrubber male condoms prevent pregnancy, but do not prevent HIV transmission. A specialist in contact dermatitis suggests that rubber sensitive men use a nonrubber condom directly over the penis and then cover that condom with a rubber condom to protect against HIV transmission. A nonlatex thermoplastic elastomer has been used to make male condoms since the early 1990s, but FDA has yet to approve it. A recent article suggests that a thermoplastic elastomer may be the only choice for rubber sensitive males. FDA approval will increase the availability of a nonlatex thermoplastic elastomer condom. The contact dermatitis specialist reviews and follows up on other articles he has written over the last 20 years. Topics include ethylene oxide burns in hospitalized patients, paraben paradox, benzocaine as a contaminant in sunscreens containing glyceryl PABA, sensitivity to nickel, misuse of a patch test to detect hypersensitivity to mercury amalgam dental fillings, permanent destruction of the fingernails due to an allergic reaction to an acrylic nail preparation, and dermatitis due to visual display units.^ieng

Fiberglass vs mineral wool (rockwool) dermatitis.

Fiberglass and rockwool dermatitis is usually due to a mechanical irritant reaction. When several members of a family are affected, scabies is often initially suspected. The irritant dermatitis may be complicated by an urticarial and an eczematous reaction which may mimic an allergic reaction clinically and histologically. Allergic reactions to added epoxy or formaldehyde resins may very rarely occur.

Systemic contact dermatitis from Orinase and Diabinese in diabetics with para-amino hypersensitivity.

Diabetic patients sensitized by topical medication containing such para-amino compounds as sulfanilamide and benzocaine can acquire a widespread eczematous "systemic" contact dermatitis from the oral administration of such para-amino hypoglycemic drugs as Orinase or Diabinese.

Management of "consort dermatitis" due to combined allergy: seminal fluid and latex condoms.

PIP: Belgian dermatologists recently reported what is probably the first case of combined seminal fluid and latex allergy. A young atopic woman presented with the clinical symptoms of swelling and a burning sensation on the vulva and in the vulvovaginal area during or after coitus, followed by vesiculation, lichenification, and generalized eczema. Diagnosis was confirmed by the appropriate testing methods. The author treated a 34-year old nurse who had an immediate type I reaction to seminal fluid documented by results of radioallergosorbent and prick tests. The patient also has an history of contact urticaria due to latex gloves and rubber condoms. Nonrubber condoms, such as Lambskin condoms, made from processed sheep intestines, may be recommended for use by patients with this type of combined allergy. These condoms do not, however, protect against HIV infection. To protect against HIV infection, the male partner must wear a rubber condom with a Lambskin condom over the rubber one to protect his partner from allergy. Otherwise, the female condom may be used, for it is made of nonsensitizing polyurethane. In this case, the doctor gave Tactylon nonlatex synthetic elastomer condoms to the husband. The condoms, yet to be approved by the US Food and Drug Administration, are made by the manufacturer of Tactylon nonlatex gloves. The nurse use the gloves at work without experiencing an allergic reaction.^ieng

Allergic contact dermatitis to nonoxynol-9 in a condom.

PIP: Nonoxynols are ethoxylated alkyl phenols or nonylphenylethers. Many condoms contain nonoxynol-9, a nonionic, surfactant-effective spermicide with a very low rate of toxic effects in humans. It is a very rare sensitizer which is compatible with latex and silicone lubricants used in condoms in a range of 1-12%. Nonoxynol-9 is also microbicidal against many organisms including HIV, the herpes viruses, Gonococcus, Treponema, Trichomonas, and hepatitis B. The unique case of a 32-year-old man experiencing allergic contact dermatitis to nonoxynol-9 is reported. A female allergic reaction was, however, reported in Holland, while several cases of allergic reactions to nonoxynol compounds have been reported in Belgium. Nonoxynol is also known to potentially cause allergic contact dermatitis when encountered in waterless hand cleansers and in detergents. The author notes that individuals experiencing irritation from high concentrations of nonoxynol should try a product with a lower concentration. Concern has been expressed that nonoxynol-9 through its detergent action and cytotoxicity may digest nonspecific protective mucosal coatings and induce hyperemia which by itself might promote HIV and other viral infections. Neither the safety nor efficacy of spermicides in preventing sexually transmitted infections in the anal canal or oropharynx has been studied.^ieng

Reactions at silicone-injected sites on the face associated with silicone breast implant "inflammation" or "rejection".

Although complications in various parts of the body have been suggested as being produced when silicone mammary implants are "rejected" or produce inflammation, there have apparently been no reports describing "flares" at previous sites of facial silicone injections as complications of mammary silicone implants. Such reactions appear to be comparable to so-called "systemic contact dermatitis." However, in the absence of results of skin testing, the mechanism of such "ectopic" flares remains in doubt.

Allergic stomatitis from dental impression compounds.

Two women experienced a severe stomatitis following brief contact with Impregum, a dental impression material. In one patient it was shown that the sensitizer was the catalyst 2,5 dichlorobenzene sulfonate. This dental impression material is widely used in the United States, and has been reported as a sensitizer in Europe. The catalyst in Scutan, another dental impression compound sometimes used instead of the methacrylates, has also been reported in Europe as being a sensitizer.

Contact urticaria due to polyethylene glycol.

Contact dermatitis developed in a patient from the use of Tinactin and Lotrimin solutions. Initially, the usual 'delayed' type of allergic contact dermatitis was suspected. However, covered patch tests gave negative results after forty-eight hours. 'Open' testing revealed an 'immediate' urticarial reaction to polyethylene glycol, which is used as a solvent in both antifungal agents. It should be emphasized that after a patient scratches or irritates an urticarial contact dermatitis, the resulting eruption closely resembles contact dermatitis of the usual delayed variety. Apparently, this is the first written report of such an 'immediate' reaction to polyethylene glycol. Although the modern, elegant antifungal agents with their complex vehicles are quite effective, one sometimes becomes nostalgic for the old-fashioned, inelegant but effective Whitfield's ointment (salicylic acid and benzoic acid) with its simple, nonsensitizing petrolatum base.

Condom dermatitis in either partner.

PIP: Condom sales rose in the 1980s because condoms protect against the spread of sexually transmitted diseases and AIDS. In anticipation of corresponding increase in the incidence of condom dermatitis, a dermatologist prepared a brief overview of the condition and ways to treat it to prepare health professional for the anticipated increase. In men, allergic reactions may consist of edema of the penis, especially the prepuce; penile itching; and eczematous dermatitis which extends to the scrotum, inguinal areas, and the inner thighs. Symptoms in women vary and may include pubic and groin dermatitis, vulvitis, pruritus vulvae, a burning vaginal sensation, vulval redness and edema, and eczema on nearby skin. Antioxidants or accelerators in the rubber are generally responsible for condom dermatitis. When a health professional believes the dermatitis to be allergic rubber condom dermatitis, he/she should request patch tests for the same make of condom that came in contact with the patient and for rubber chemicals known to induce an allergic reaction, e.g., mercaptobenzothiazole (MBT). To assist, the dermatologist includes a patch test series for such allergens. Natural latex condoms and condoms made of processed sheep intestine cecum may prevent most allergic reactions. Sometimes patients are allergic to condom lubricants, and not the rubber itself. Health professionals must be sure to inform dermatitis patients allergic to the lubricant to not switch to oils or petroleum jelly because they destroy the rubber. Spermicidal contraceptive agents also can cause contact dermatitis, particularly nonoxynol 9. A condom with corn starch can produce urticaria. Further, paralyzed male patients are especially prone to allergic dermatitis from either the rubber in the condom urinals and/or the medical adhesive.^ieng