bluuebunny/crossref_metadata_2025 huggingface dataset:
Acetone
Authors: Johanson Gunnar
Published: August 2012

Acetone is the simplest example of the ketones. It is a clear, colorless, mobile liquid. Acetone is completely miscible with water and most organic solvents and oils. It therefore serves as an important industrial solvent for cleaning, as a common building block in organic chemistry, and as a precursor to polymers. Well‐known domestic uses of acetone are as the active ingredient in nail polish remover and as paint thinner.

Acetone is the most widely used ketone in industry. It is used primarily to synthesize methacrylates, about half of the world's production of acetone is used as a precursor to methyl methacrylate. Other large‐scale chemicals derived from acetone are bisphenol A and methyl isobutyl ketone. Acetone is also used as a process solvent in the manufacture of cellulose acetate yarn, smokeless gun powder, surface coatings, and various pharmaceutical and cosmetic products. Other solvent uses include paint, ink, resin, and varnish formulations; thinning of fiberglass resin; cleaning of fiberglass tools; and dissolution of two‐part epoxies and superglues before hardening.

Acetone is a normal by‐product of mammalian metabolism and is thus found in all tissues, including blood, as well as in urine and breath. The levels vary, depending on nutritional and metabolic conditions, and are increased in obese compared with slim people and in working compared with resting people. Diabetic patients show markedly elevated levels of acetone.

Acetone is readily taken up via inhalation if present in ambient air and via the gastrointestinal tract if ingested. Uptake via skin is of minor importance. However, due to its excellent solvent properties, acetone readily removes water from the skin. This impairs the barrier properties and makes the skin more vulnerable to other irritating, sensitizing, or infectious agents.

Compared with many other industrial solvents, acetone is of relatively low toxicity. The critical effect, that is, the first effect that appears as the exposure level increases, is mild respiratory tract and eye irritation. At higher exposures, CNS effects such as lightheadedness and headache are observed. In general, signs and symptoms of acetone intoxication, such as vomiting, convulsions, and unconsciousness, are nonspecific. Acetone is rapidly cleared from the body, mainly by metabolism and, to some extent, by excretion via breath and urine, and toxic effects after chronic exposure in general agree with those following acute exposure.

Reproductive and developmental effects appear only after much higher doses of acetone than those causing irritation and CNS effects. Genotoxicity is not observedin vitroandin vivo. No carcinogenicity studies are available. Limited data from tumor promotion studies, using acetone as a vehicle or a promoter, suggest that dermally applied acetone is not tumorigenic.
Ketones of Six to Thirteen Carbons
Authors: O'Donoghue John L.
Published: August 2012

Ketones of carbon number 6–13 are important commercial and industrial materials. Their primary use is as solvents in numerous products and industrial applications. Owing to their volatility, environmental regulations have been directed at restricting emissions, particularly to the atmosphere. A number of the ketones discussed in this chapter not only can undergo photochemical transformations that contribute to their abiotic degradation but also may contribute to the formation of smog. Regulations limiting or prohibiting release of materials that may contribute to smog formation are leading to reductions in the use of some of these materials.

As for the short‐chain ketones discussed in Chapter 53, the ketones covered in this chapter are of concern mainly due to inhalation and dermal exposure routes. Acute exposure to high vapor concentrations of these materials may result in narcosis; however, such exposures are rare except in cases of accidents.

Low levels of exposure to many of these ketones can be expected in the environment and through endogenous exposure because ketones are common substrates for many of the enzymes associated with intermediary metabolism in organisms from bacteria to man.
Monohydric Alcohols: C1to C6
Authors: Bevan C.
Published: August 2012

The present chapter summarizes monohydric aliphatic C1 to C6 alcohols. These alcohols exist as volatile liquids at ambient temperatures, and exposure can occur in both industrial and nonindustrial environments. Generally, few or minor problems have been reported with the use of these alcohols in the workplace where the major routes of exposure are dermal or inhalation. Methanol, ethanol, propanols and butanols are known to cause adverse effects when ingested; however, ingestion is not a major route of occupational exposure. A common property of some of the alcohols is to produce local irritation to the skin, eyes, and respiratory tract. Although central nervous system (CNS) depressants, few alcohols produce neuropathic effects in humans. Abuse of products containing methanol and ethanol has produced some indications of neurotoxicity in humans, but nothing has been reported in an occupational environment. 2‐Hexanol produces neurotoxicity by the oral and intraperitoneal routes in animals, but there is no evidence of such an effect having occurred in the workplace. There is no clear evidence that occupational exposures to alcohols represent a carcinogenic risk to humans. Some of these alcohols such as ethanol and isopropanol can enhance the toxic effects of various chemicals, particularly hepatotoxins. This effect is likely due to an inductive effect of the alcohol on microsomal enzymes, particularly the cytochrome P450 system, which may allow a greater metabolic conversion of the hepatotoxin to its toxic metabolite.
Occupational Ergonomics: Principles and Applications
Authors: Bhattacharya Amit , Talbott Nancy , Kincl Laurel
Published: August 2012

This chapter provides the basic principles that underlie the field of ergonomics and their application to some of the current issues of importance in the workplace. Sections 2–4 deal with the physiology of muscles; biomechanics; cellular responses to tissue, nerve, and joint injuries as they relate to cumulative trauma disorders; and common types of overuse syndromes. The remaining sections deal with applications of the principles to workplace ergonomic issues and proposed ergonomic regulations.

The word “ergonomics” is made up of two Greek words, “ergo” meaning work and “nomas” meaning laws. The field of ergonomics is highly interdisciplinary. It applies principles from engineering, physiology, medicine, and psychology to the understanding of the interaction of humans with their workplace. The interaction of humans with their workplace may consist of identifying the relationship between job physical risk factors and physiological responses. For example, a specific ergonomic problem of paramount importance in the occupational health and safety is the issue of work‐related musculoskeletal disorders (WMD). Some of these issues are discussed further in this chapter. The specific areas of application relevant to the field of ergonomics are defined and briefly explained.

Activities that involve repetitive stress have effects that are extremely complicated. Adding internal or external forces to the body can, as described, alter bone, joints, ligaments, tendons, nerves, and muscles. Belief that a repetitive motion will result in an isolated nerve injury without affecting surrounding joints, ligaments, muscles, or tendons is likely to inhibit appropriate care and control of exposed individuals. Additional research is needed to further characterize changes that occur, and current approaches to recognizing, managing, and preventing repetitive injuries must address all tissues in the involved area.
Abnormal Pressures: Hyperbaric and Hypobaric
Authors: (Bill) Hamilton (Deceased) R. W.
Published: August 2012

This chapter deals with the interrelated physiological (or toxicological) effects of altered ambient pressure, the pressure continuum from deep sea to outer space. Pressures may be both higher and lower than the sea‐level pressure to which we are accustomed and in which we have evolved.

The chapter first discusses what pressure is, and where and why alternative pressures are encountered by humans. It reviews the occupational, medical, and recreational incentives for forays into both environments, high and low. It points out the role of time in evaluating the effects of pressure exposures and the importance of transitions to and from higher and lower pressures. Next, it covers first the effects of elevated pressures, then the effects of lack of pressure, emphasizing the importance of breathing gases in most alternative pressures. Last, it pays particular attention to the main pressure‐related disorder, decompression sickness, and its treatment.
Biological Rhythms, Shiftwork, and Occupational Health
Authors: Scott Allene J.
Published: August 2012

“… and God divided the light from the darkness, and God called the lightday, and the darkness He callednight. And the evening and the morning were the first day” (Genesis 1:4–5, King James Version). So from the beginning, day/night periodicity has been an important environmental influence on life on earth. For diurnal species, like human beings, the sunlight portion of the day is the time for activity and the dark, nighttime for sleeping.

Although we are under the influence of environmental rhythms, such as the daylight–night cycle, we are also under the physiological influence of our own internal biological clock. Normally synchronization of biological rhythms with each other and with environmental rhythms (external time cues) maximizes our waking and sleeping performance and promotes overall well‐being. Night work is opposed to the innate drive to sleep at night and work during the daytime and results in an unnatural mismatch of environmental and internal time cues. Shiftworkers are exposed to disruptive effects of schedule‐related time shifts on the normal synchronization of individual biological rhythms with each other as well as with the external time cues.

This chapter reviews basic chronobiological principles as they relate to shiftworker safety and health. Studies dealing with the effects of time shifts on sleep, alertness, and performance rhythms are discussed. Research exploring the consequences of shiftwork on physical and mental health is reviewed. Countermeasures for minimizing adverse health and safety effects of sleep deprivation and biological rhythm disruption are presented. Industrial hygiene considerations related to control of worker exposure to potential toxins during extended and rotating shifts are considered. Finally, international and U.S. regulatory policy regarding shiftwork scheduling and special medical provisions for shiftworkers are reviewed.
Pharmaceuticals
Authors: Acosta Daniel
Published: August 2012

This chapter provides a comprehensive summary of common adverse side effects associated with key pharmaceutical drugs used in the treatment of selected diseases and disorders. The focus of this chapter is on the use of drugs associated with key organs and physiological functions of the body. The main topics covered are anesthetics, analgesics, sedative hypnotics, antipsychotics, antiepileptics, neurodegenerative disorders, adrenergic and cholinergic agents, cardiovascular drugs, and hormone antagonists.
Engineered Nanomaterials
Authors: Kosnett Michael J. , Woskie Susan
Published: August 2012

Engineered nanomaterials (ENM) represent an emerging technology with a wide range of industrial and medical applications. The toxicity of nanomaterials may vary considerably depending on numerous variables, including but not limited to composition (including impurities), size, shape, charge, aggregation status, solubility, and surface characteristics. Although this poses a challenge to the development of occupational exposure limits (OELs), some OELs have recently been proposed for selected ENMs. Based on animal data and findings associated with ambient nanoparticulates, health concerns for ENMs have focused on cardiovascular and pulmonary endpoints. The potential for exposure to ENMs can occur across the lifecycle. A precautionary approach that focuses on prevention of potential exposures and toxicity evaluation aimed at the sustainable production of these potentially valuable new products is recommended. Although there is no consensus on the value of instituting routine medical surveillance targeted to workers with potential exposure to nanomaterials, the potential utility of nanomaterial worker exposure registries has received increasing attention.
On the Effect of Atomic Structure on the Activity and Deactivation of Catalytic Gold Nanoparticles
Authors: Walsh Michael J. , Yoshida Kenta , Pay Mungo L. , Gai Pratibha L. , Boyes Edward D.
Published: August 2012

We present studies of the structure and stability of catalytic gold nanoparticles through in situ aberration‐corrected electron microscopy to investigate the effect of heating on the nature of the identified atomic active sites. Low coordination surface atoms are replaced by atomically clean surface facets through local rearrangements to minimise surface energy. The associated movement of surface atoms is proposed to directly precede Ostwald ripening. Expansive surface strain resulting from inherently strained structures, such as the decahedra, is shown to diminish with increasing particle size and the associated elastic energy is reduced through a shifting of the disclination axis towards the particle surface. At elevated temperatures a reduction in surface energy anisotropy may lead to energetically favourable morphologies with minimal intrinsic strain. Such processes will act as structural deactivation mechanisms, resulting in a loss of active sites without any necessary associated loss of surface area or change in particle size through traditional sintering mechanisms. Considerations of the active site stability and the particle size according to the reaction conditions are described.
A New Biosensor for Chiral Recognition Using Goat and Rabbit Serum Albumin Self‐Assembled Quartz Crystal Microbalance
Authors: Chen Wen‐Jing , Zhang Sheng , Zhang Wei‐Guang , Fan Jun , Yin Xia , Zheng Sheng‐Run , Su Wen‐Cui , Zhang Zhi , Hong Tao
Published: August 2012

Quartz crystal microbalance (QCM) biosensor was used for the chiral recognition of five pairs of enantiomers by using goat serum albumin (GSA) and rabbit serum albumin (RbSA) as chiral selectors. Serum albumin (SA) was immobilized on the QCM through the self‐assembled monolayer technique, and the surface concentration of GSA and RbSA were 8.8 × 10−12  mol cm−2 and 1.2 × 10−11 mol cm−2, respectively. The QCM biosensors showed excellent sensitivity and selectivity. Meanwhile, the chiral recognition of SA sensors was quite species dependent. There were differences between GSA and RbSA sensors in the ability and the preference of chiral recognition. To R,S‐1,2,3,4‐tetrahydro‐1‐naphthylamine (R,S‐1‐TNA), R,S‐1‐(4‐methoxyphenyl)ethylamine (R,S‐4‐MPEA), and R,S‐1‐(3‐methoxyphenyl)ethylamine (R,S‐3‐MPEA), the preference of the stereoselective SA‐drug binding of the two kinds of SA sensors were consistent. However, to R,S‐2‐octanol (R, S‐2‐OT) and R,S‐methyl lactate (R,S‐MEL), the two kinds of SA sensors had opposite chiral recognition preference. Moreover, the interactions of SA and the five pairs of enantiomers have been further investigated through ultraviolet (UV) and fluorescent (FL) spectra. The UV/FL results were in accordance with the consequence of QCM. Chirality 24:804–809, 2012. © 2012 Wiley Periodicals, Inc.
Gallium Trichloride Catalyzed Hydroamination of Alkynes: Scope, Limitation, and Mechanistic Studies by DFT
Authors: Li Lei , Huang Genping , Chen Zhou , Liu Wei , Wang Xiufang , Chen Yanmei , Yang Lijuan , Li Wu , Li Yahong
Published: August 2012

The successful application of gallium trichloride as a catalyst for the intermolecular hydroamination of alkynes with aromatic amines is reported. The reaction is effective with many aniline derivatives and shows exclusive selectivity for the Markovnikov products. The mechanism of the transformation was investigated by DFT calculations and a plausible pathway is proposed.
Mercury concentrations of a resident freshwater forage fish at Adak Island, Aleutian Archipelago, Alaska
Authors: Kenney Leah A. , von Hippel Frank A. , Willacker James J. , O'Hara Todd M.
Published: August 2012

The Aleutian Archipelago is an isolated arc of over 300 volcanic islands stretching 1,600 km across the interface of the Bering Sea and North Pacific Ocean. Although remote, some Aleutian Islands were heavily impacted by military activities from World War II until recently and were exposed to anthropogenic contaminants, including mercury (Hg). Mercury is also delivered to these islands via global atmospheric transport, prevailing ocean currents, and biotransport by migratory species. Mercury contamination of freshwater ecosystems is poorly understood in this region. Total Hg (THg) concentrations were measured in threespine stickleback fish (Gasterosteus aculeatus) collected from eight lakes at Adak Island, an island in the center of the archipelago with a long military history. Mean THg concentrations for fish whole-body homogenates for all lakes ranged from 0.314 to 0.560 mg/kg dry weight. Stickleback collected from seabird-associated lakes had significantly higher concentrations of THg compared to non-seabird lakes, including all military lakes. The δ13C stable isotope ratios of stickleback collected from seabird lakes suggest an input of marine-derived nutrients and/or marine-derived Hg. Environ. Toxicol. Chem. 2012; 31: 2647–2652. © 2012 SETAC
Novel differential diagnostic method for superficial/deep tumor of the parotid gland using ultrasonography
Authors: Higashino Masaaki , Kawata Ryo , Haginomori Shin‐Ichi , Lee Koutetsu , Yoshimura Katsuhiro , Inui Takaki , Nishikawa Shuji
Published: August 2012

Background

The purpose of this study was to prepare the ultrasonographic diagnostic criteria on parotid tumors for preoperative differentiation of superficial and deep tumors.

Methods

We evaluated 154 patients with a benign parotid tumor who underwent surgery. The minimum thickness of normal parotid gland tissue between the parotideomasseteric fascia and tumor (minimum fascia–tumor distance [MFTD]) was measured on preoperative ultrasonography and compared among tumors at different locations, and the optimum cutoff value to differentiate a deep tumor was identified.

Results

The MFTD showed significant differences between superficial and deep tumors and between inferior pole and deep tumors. The sensitivity, specificity, and accuracy of an MFTD ≥3 mm for the differentiation of deep tumors were 85%, 91%, and 89%.

Conclusion

A tumor with an MFTD ≥3 mm on preoperative ultrasonography is very likely to be a deep tumor based on a new differentiation method for deep parotid tumors considering those present at other locations. Head Neck, 2013
Uncommon presentations of parathyroid adenoma
Authors: Givens Daniel J. , Hunt Jason P. , Bentz Brandon G.
Published: August 2012

Background

Patients with parathyroid adenomas (PAs) are commonly encountered in otolaryngology and may present with asymptomatic hypercalcemia. Retropharyngeal hematoma and recurrent laryngeal nerve (RLN) paralysis are less commonly encountered presentations and may be harbingers of a malignant process.

Methods and Results

We present 2 patients with rare presentations of parathyroid adenoma. The first is a 57‐year‐old man with retropharyngeal hemorrhage and progressive airway compromise. The second is a 51‐year‐old woman presenting with dysphonia who was found to have RLN paralysis. Both of these patients were found to have benign disease.

Conclusions

Although most patients with PA present with asymptomatic hypercalcemia, this disease entity must be considered in patients with other unusual presentations including hemorrhagic neck masses and dysphonia. The importance of a broad differential diagnosis and thorough workup is emphasized. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Feasibility and safety of minimal‐incision thyroidectomy for Graves' disease: A prospective, single‐center study
Authors: Perigli Giuliano , Qirici Etleva , Badii Benedetta , Kokomani Aurora , Staderini Fabio , Luconi Michaela , Crescioli Clara , Mannelli Massimo , Maggi Mario , Cianchi Fabio
Published: August 2012

Background

The role of minimally invasive surgery in Graves' disease is still controversial. The aim of this study was to compare the clinical outcomes of patients undergoing minimal‐incision thyroidectomy with those undergoing conventional thyroidectomy for Graves' disease.

Methods

A prospective study was performed on 148 patients undergoing total thyroidectomy. Seventy‐one patients underwent minimal‐incision thyroidectomy and 77 underwent conventional thyroidectomy. Minimal‐incision thyroidectomy was proposed if the thyroid volume was ≤50 mL.

Results

There were no significant differences in the operative time between minimal‐incision thyroidectomy and conventional thyroidectomy. The length of skin incision was significantly shorter in the minimal‐incision thyroidectomy than that in the conventional thyroidectomy group. The incidence of postoperative complications was similar in the 2 groups. Patients undergoing minimal‐incision thyroidectomy experienced significantly less postoperative pain and were more satisfied with the cosmetic result than patients who underwent conventional thyroidectomy.

Conclusions

Minimal‐incision thyroidectomy is a feasible and safe option for the surgical treatment of selected patients with Graves' disease. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Effect of erlotinib on epidermal growth factor receptor and downstream signaling in oral cavity squamous cell carcinoma
Authors: Tsien Christina I. , Nyati Mukesh K. , Ahsan Aarif , Ramanand Susmita G. , Chepeha Douglas B. , Worden Francis P. , Helman Joseph I. , D'Silva Nisha , Bradford Carol R. , Wolf Gregory T. , Lawrence Theodore S. , Eisbruch Avraham
Published: August 2012

Background

The purpose of this study was to determine if there are differences in biomarker modulation and epidermal growth factor receptor (EGFR) degradation between the tumor and the normal mucosa after treatment with an EGFR inhibitor, erlotinib, in head and neck cancer.

Methods

Patients with primary oral cavity squamous cell cancers received a course of erlotinib, 150 mg every day for 7 days before surgical resection. Tumor and normal mucosa biopsies were obtained both pre‐erlotinib and post‐erlotinib. Changes in known markers of EGFR activity (phospho, AKT, STAT3) were measured by immunoblotting, whereas changes in tissue distribution were analyzed by immunohistochemical analysis.

Results

Twelve patients were enrolled; 7 had evaluable paired tumors and normal mucosa biopsies pretreatment and posttreatment. Expression of EGFR was higher in tumors compared to the normal mucosa (p = .005). Erlotinib administration was associated with marked inhibition of phosphorylated epidermal growth factor receptor (pEGFR) and reduction in total EGFR protein (p = .004, p = .007) in tumors, whereas there was heterogeneity in EGFR inhibition in the normal mucosa (p = .10 [pEGFR], and p = .07 [EGFR]). Reduced levels of pSrc and pSTAT3 and enhanced p27 levels were noted in tumors after erlotinib. Cell culture studies confirmed that EGFR is degraded in tumor cells after prolonged treatment with erlotinib.

Conclusion

Our results show that EGFR inhibition by erlotinib led to a marked reduction in EGFR protein levels in patients. Differential effects of erlotinib on tumors compared to the normal mucosa suggest there may be individual patient heterogeneity. These preliminary data suggest EGFR degradation should be further analyzed as a potential biomarker in selecting patients likely to benefit from EGFR inhibitors. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Frozen biopsy of central compartment in papillary thyroid cancer: Quantitative nodal analysis
Authors: Lim Yun‐Sung , Choi Sung‐Won , Lee Yoon Se , Lee Jin‐Choon , Lee Byung‐Joo , Wang Soo‐Geun , Son Seok‐Man , Kim In‐Ju , Shin Dong‐Hoon
Published: August 2012

Background

Nodal metastasis in papillary thyroid cancer (PTC) usually occurs in the central compartment of the ipsilateral neck and spreads laterally. The purpose of this study was to evaluate the diagnostic accuracy of frozen biopsy for quantitative nodal evaluation of central neck metastasis in PTC.

Methods

In all, 252 patients with PTC underwent total thyroidectomy with bilateral central neck dissection (CND). All tissues from ipsilateral CND were examined by frozen biopsy.

Results

Among them, 53% of patients had central neck metastasis. The sensitivity and specificity of frozen biopsy for central neck metastasis were 92% and 99%, respectively. The positive predictive value and the negative predictive value were 99% and 84%, respectively. The diagnostic accuracy for the exact number of metastatic nodes was 91% compared to permanent biopsy.

Conclusions

Frozen biopsy for quantitative analysis of central compartment is a useful tool for the precise evaluation of central lymphatic status intraoperatively with a high sensitivity and specificity. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Impact of chemotherapeutic agents on the immunostimulatory properties of human 6‐sulfo LacNAc+ (slan) dendritic cells
Authors: Wehner Rebekka , Bitterlich Anna , Meyer Nicole , Kloß Anja , Schäkel Knut , Bachmann Michael , Schmitz Marc
Published: August 2012

Chemotherapy is an important treatment modality for many patients with advanced cancer. Recent data revealed that certain chemotherapeutic agents differentially affect maturation, cytokine production and T‐cell stimulatory capacity of dendritic cells (DCs), which play a crucial role in the induction of antitumor immunity. Whereas most reports are based on mouse or human monocyte‐derived DCs, studies investigating the direct effect of chemotherapeutic drugs on native human DCs are rather limited. Here, we evaluated the impact of various chemotherapeutic drugs on the immunostimulatory properties of 6‐sulfo LacNAc+ (slan) DCs, representing a major subpopulation of human blood DCs. Because of their various antitumor effects, slanDCs may essentially contribute to the immune defense against tumors. We demonstrated that doxorubicin and vinblastine significantly impair the release of tumor necrosis factor‐α, interleukin (IL)‐6 and IL‐12 by slanDCs. Functional data revealed that both drugs inhibit slanDC‐mediated proliferation of T lymphocytes and their capacity to differentiate naive CD4+ T cells into proinflammatory T‐helper type I cells. Furthermore, these agents markedly suppressed the ability of slanDCs to stimulate interferon‐γ secretion by natural killer (NK) cells. In contrast, paclitaxel, mitomycin C and methotrexate sustained the ability of slanDCs to produce proinflammatory cytokines and their potential to activate T‐lymphocytes and NK cells. These results indicate that doxorubicin and vinblastine impair the ability of native human DCs to stimulate important immune effector cells, whereas methotrexate, mitomycin C and paclitaxel maintain their immunostimulatory properties. These novel findings may have implications for the design of treatment modalities for tumor patients combining immunotherapeutic strategies and chemotherapy.
A Non‐Feeding Pilidium With Apparent Prototroch and Telotroch
Authors: Maslakova Svetlana A. , von Dassow George
Published: August 2012

The nemertean pilidium larva is a long‐lived planktotrophic form which is challenging to homologize to other invertebrate larval forms. Here we report a reduced, lecithotrophic pilidium which superficially resembles a trochophore. We document the pilidium‐like catastrophic metamorphosis of this larva, including devouring of the larval body. Sequences of COI and 16S rRNA show that this larva belongs to an undescribed lineiform species. This novel larval form highlights the long‐standing question, is the trochophore a conserved larval ground‐plan or a functional design arrived at by convergence? J. Exp. Zool. (Mol. Dev. Evol.) 318B:586–590,2012 © 2012 Wiley Periodicals, Inc.
Preparative separation of bioactive compounds from essential oil of Flaveria bidentis (L.) Kuntze using steam distillation extraction and one step high‐speed counter‐current chromatography
Authors: Wei Yun , Du Jilin , Lu Yuanyuan
Published: August 2012

In order to utilize and control the invasive weed, bioactive compounds from essential oil of Flaveria bidentis (L.) Kuntze were studied. Steam distillation extraction and one step high‐speed counter‐current chromatography were applied to separate and purify the caryophyllene oxide, 7,11‐dimethyl‐3‐methylene‐1,6,10‐dodecatriene, and caryophyllene from essential oil of Flaveria bidentis (L.) Kuntze. The two‐phase solvent system containing n‐hexane/acetonitrile/ethanol (5:4:3, v/v/v) was selected for the one step separation mode according to the partition coefficient values (K) of the target compounds and the separation factor (α). The purity of each isolated fraction after a single high‐speed counter‐current chromatography run was determined by high performance liquid chromatography. A 3.2 mg of caryophyllene oxide at a purity of 92.6%, 10.4 mg of 7,11‐dimethyl‐3‐methylene‐1,6,10‐dodecatriene at a purity of 99.1% and 5.7 mg of caryophyllene at a purity of 98.8% were obtained from 200 mg essential oil of Flaveria bidentis (L.) Kuntze. The chemical structures of these components were identified by GC‐MS, 1H‐NMR, and 13C‐NMR.
Activation–Deactivation Equilibrium Associated With Iron‐Mediated Atom‐Transfer Radical Polymerization up to High Pressure
Authors: Schroeder Hendrik , Yalalov Denis , Buback Michael , Matyjaszewski Krzysztof
Published: August 2012

The equilibrium constant, Kmodel, of iron‐mediated atom‐transfer radical polymerization (ATRP) is investigated for FeBr2/α‐bromoester model systems in the absence of monomer. Quantitative analysis is carried out in solution of either N‐methylpyrrolidin‐2‐one (NMP) or acetonitrile (MeCN) via high‐pressure online VIS/NIR spectroscopy monitoring the formation of the FeIII species. The reaction volume is determined to be ΔVR = 13 ± 3 cm3 mol−1, which indicates that Kmodel decreases with pressure. This observation points to preferred formation of catalytically inactive or less active iron–solvent complexes toward higher pressure. Thus suitable solvent selection is important for the development of efficient iron‐based ATRP catalysts.
Mediating and moderating effects of learned resourcefulness on depressive symptoms and positive ideation in hospital nurses in Taiwan
Authors: Chung Chun‐Chih , Lin Mei‐Feng , Ching Yung‐Chieh , Kao Ching‐Chiu , Chou Yi‐Ying , Ho Ping‐Hui , Chang Hsiu‐Ju
Published: August 2012

Learned resourcefulness (LR) is important in facilitating mental health in individuals experiencing depression, and positive ideation plays a further protective role in the prevention of suicidal ideation. The purpose of this study was to explore whether LR mediates or moderates the relationship between depressive symptoms and positive ideation in hospital nurses. Participants were 807 full‐time hospital nurses. The relationship between depressive symptoms and positive ideation was both mediated and moderated by LR after controlling for age, job title, and marital status. Continuing education and counseling strategies may increase nurses' LR and thereby enhance positive ideation and reduce risk of depression and suicide. © 2012 Wiley Periodicals, Inc. Res Nurs Health 35:576–588, 2012
Androgen deprivation induces senescence characteristics in prostate cancer cells in vitro and in vivo
Authors: Ewald Jonathan A. , Desotelle Joshua A. , Church Dawn R. , Yang Bing , Huang Wei , Laurila Timo A. , Jarrard David F.
Published: August 2012

BACKGROUND

The treatment of non‐localized prostate cancer involves androgen deprivation (AD) therapy which results in tumor regression. Apoptosis has been implicated in the tumor response to AD, but constitutes a small fraction of the total tumor at any time. Cellular senescence is a response to sub‐lethal stress in which cells are persistently growth arrested and develop distinct morphological and biochemical characteristics. The occurrence of senescence in prostate tumor tissue after AD therapy has not previously been investigated.

METHODS

Phenotypic and molecular characteristics of senescence were examined in models of androgen‐sensitive prostate cancer after AD and compared with androgen‐intact controls.

RESULTS

In vitro in LNCaP cells, AD induced elevated senescence‐associated β‐galactosidase (SA‐β‐gal) staining, decreased proliferation, and increased flow cytometric side scatter while minimally affecting cell viability. The increased expression of the senescence‐related proteins Glb1, the cyclin‐dependent kinase inhibitor p27Kip1 and chromatin‐regulating heterochromatin protein 1γ (HP1γ) were detected in LNCaP cells after AD in vitro by immunoblot and immunofluorescence microscopy. In mice bearing LuCaP xenograft tumors in vivo, surgical castration similarly increased SA‐β‐gal staining, increased expression of p27Kip1 and HP1γ, and decreased expression of the proliferation marker KI‐67, with minimal induction of apoptosis identified by detection of cleaved caspase 3 and TUNEL. Immunohistochemical analysis of human prostate tumors removed after AD shows similar induction of Glb1, HP1γ and decreased KI‐67.

CONCLUSIONS

We conclude that AD induces characteristics consistent with cellular senescence in androgen‐sensitive prostate cancer cells. This finding may explain incomplete tumor regression in response to AD. Prostate 73: 337–345, 2013. © 2012 Wiley Periodicals, Inc.
Dislocation motion in Sb‐doped SiGe on Si substrate
Authors: Yamashita Yoshifumi , Matsunaga Takuya , Funaki Toru , Fushimi Tatsuya , Kamiura Yoichi
Published: August 2012

We have successfully grown antimony‐doped Si1−xGex epi‐films with different doping level and a boron‐doped one on Si (001) substrate. Using these samples, we have investigated the effect of these impurities in Si1−xGex epifilm on dislocation velocity. Although dislocation velocities in the B‐doped SiGe film were comparable to those in the undoped one because of the low concentration of B, those in Sb‐doped samples are remarkably enhanced, which is qualitatively similar to the effects in bulk Si. The reduction of the activation energy of dislocation motion depended on the doping level of Sb and the amount of the reduction was 1.0 eV in the highest Sb‐concentration film. This value is significantly larger than those reported in bulk Si. The velocities in the lowest Sb‐concentration samples are also enhanced though the samples are thought to be electrically intrinsic at the temperatures where dislocation velocities were measured. Therefore, the large activation energy reduction is possibly attributed to multiple effects of the Fermi level change and other characteristic effects of the SiGe epifilm.
Possible mechanisms of switching in amorphous chalcogenides
Authors: Popescu Mihai , Velea Alin
Published: August 2012

A new description of the switching phenomenon is given. The switching is regarded as due to the formation and breaking of the links between the dendrites of crystalline nuclei in bulk materials, as a consequence of the energy pumped by an electrical field. This mechanism explains the very short switching time (<20 ns), the possibility to get smart memories based on multisteps of resistivity and the high number of cycles supported by the cell (1016). A cellular automaton mechanism was created on the basis of this model for switching. Multistage memory in chalcogenide materials has also been explained by this mechanism.
Breakdown of Stokes–Einstein relation in the supercooled liquid state of phase change materials
Authors: Sosso G. C. , Behler J. , Bernasconi M.
Published: August 2012

The application of amorphous chalcogenide alloys as data‐storage media relies on their ability to undergo an extremely fast (10–100 ns) crystallization once heated at sufficiently high temperature. However, the peculiar features that make these materials so attractive for memory devices still lack a comprehensive microscopic understanding. By means of large scale molecular dynamics simulations, we demonstrate that the supercooled liquid of the prototypical compound GeTe shows a very high atomic mobility (D ∼10−6 cm2 s−1) down to temperatures close to the glass transition temperatures. This behavior leads to a breakdown of the Stokes–Einstein relation between the self‐diffusion coefficient and the viscosity in the supercooled liquid. The results suggest that the fragility of the supercooled liquid is the key to understand the fast crystallization process in this class of materials.
Characterization of Ge2Sb2Te5 thin film alloys using conductive‐tip atomic force microscopy
Authors: Chang Chia Min , Liu Yen Ju , Tseng Ming Lun , Chu Nien‐Nan , Huang Ding‐Wei , Mansuripur Masud , Tsai Din Ping
Published: August 2012

Conductive‐tip atomic force microscopy (C‐AFM) is a powerful tool for investigating the electrical characteristics of phase‐change materials commonly used for electronic and optical data storage. We demonstrate the usefulness of this technique by examining the electrical conductivity of crystalline marks recorded with a focused laser pulse on a thin Ge2Sb2Te5 film.
Identifying Martian atmospheric instabilities and their physical origins using bred vectors
Authors: Greybush Steven J. , Kalnay Eugenia , Hoffman Matthew J. , Wilson R. John
Published: August 2012

The bred vector (BV) technique applied to the Geophysical Fluid Dynamics Laboratory (GFDL) Mars General Circulation Model (MGCM) identifies regions and seasons of instability of the Martian atmosphere, and a kinetic energy equation applied to the control and perturbed states elucidates their physical origins. Instabilities prominent in the late autumn to early spring seasons of each hemisphere along the polar temperature front result from baroclinic conversions from BV potential to BV kinetic energy near the surface, whereas both baroclinic and barotropic conversions play a role for the westerly jets aloft. The low‐level tropics and the northern hemisphere summer are relatively stable, with negative bred vector growth rates. Bred vector growth precedes initiation of travelling wave activity in the midlatitudes during the transition seasons, and their structure relates to the eddy field. Topography plays a role in determining favoured locations for near‐surface instabilities. Bred vectors are also linked to forecast ensemble spread in data assimilation and help explain the growth of forecast errors. We finally note that the ability to use breeding to identify instabilities as well as their physical origin depends on the fact that both the control and the perturbed solutions that give rise to bred vectors satisfy exactly the model's governing equations. As a result, this approach can be used with any dynamical system represented by a model. Copyright © 2012 Royal Meteorological Society
Information Visualization to Enhance Sensitivity and Selectivity in Biosensing
Authors: Oliveira Osvaldo N. , Pavinatto Felippe J. , Constantino Carlos J. L. , Paulovich Fernando V. , de Oliveira Maria Cristina F.
Published: August 2012

An overview is provided of the various methods for analyzing biosensing data, with emphasis on information visualization approaches such as multidimensional projection techniques. Emphasis is placed on the importance of data analysis methods, with a description of traditional techniques, including the advantages and limitations of linear and non-linear methods to generate layouts that emphasize similarity/dissimilarity relationships among data instances. Particularly important are recent methods that allow processing high-dimensional data, thus taking full advantage of the capabilities of modern equipment. In this area, now referred to as e-science, the choice of appropriate data analysis methods is crucial to enhance the sensitivity and selectivity of sensors and biosensors. Two types of systems deserving attention in this context are electronic noses and electronic tongues, which are made of sensor arrays whose electrical or electrochemical responses are combined to provide “finger print” information for aromas and tastes. Examples will also be given of unprecedented detection of tropical diseases, made possible with the use of multidimensional projection techniques. Furthermore, ways of using these techniques along with other information visualization methods to optimize biosensors will be discussed.
Neonatal intensive care unit‐specific screening criteria for retinopathy of prematurity
Authors: Lai Yu‐Hung , Tseng Hsing‐I. , Yang San‐Nan , Hsu Hsin‐Tien , Chen Hsiu‐Lin
Published: August 2012

This study investigated the incidence of retinopathy of prematurity (ROP) and its risk factors in a tertiary referral hospital in Taiwan to evaluate the applicability of the ROP screening guidelines published by the American Academy of Pediatrics, American Academy of Ophthalmology, and American Association for Pediatric Ophthalmology and Strabismus in 2006 (2006 guidelines). A pediatric ophthalmologist applied the 2006 guidelines to screen for ROP and to treat with laser photocoagulation in each case. We retrieved all records of premature infants referred for ROP screening at the hospital during 2004 to 2008. Univariate logistic regression analysis was applied firstly to identify factors correlating with stage 3 ROP or with laser treatment, and then those significant (p < 0.05) risk factors were analyzed by multivariate logistic regression. In the 138 male and 118 female premature infants in this study, mean gestation age was 30.8 ± 2.8 weeks, and mean birth weight was 1464.7 ± 434.2 g. The percentage of infants with ROP in at least one eye was 38.7%. Thirty two (12.5%) had ROP stage 3 or higher in at least one eye. Multivariate logistic regression analysis showed that the best predictors of type 1 pre‐threshold ROP (requiring laser treatment) were young gestational age, low birth weight and male gender. As medical care of extremely premature infants improves, timely identification and treatment of conditions such as ROP are essential. Although the incidence of ROP in this institute was comparable to that in developing countries and higher than that in developed countries, the 2006 guidelines originally developed for a United States population were still applicable. However, the 2006 guidelines should be modified for a Taiwan population by considering gender.
A Systematic Review of the Evidence for Complete Decongestive Therapy in the Treatment of Lymphedema From 2004 to 2011
Authors: Lasinski Bonnie B. , Thrift Kathryn McKillip , Squire DeCourcy , Austin Melanie K. , Smith Kandis M. , Wanchai Ausanee , Green Jason M. , Stewart Bob R. , Cormier Janice N. , Armer Jane M.
Published: August 2012

Objective

To critically analyze the contemporary published research that pertains to the individual components of complete decongestive therapy (CDT), as well as CDT as a bundled intervention in the treatment of lymphedema.

Data Sources

Publications were retrieved from 11 major medical indices for articles published from 2004‐2010 by using search terms for lymphedema and management approaches. Literature archives of the authors and reference lists were examined through 2011.

Study Selection

A research librarian assisted with initial literature searches by using search terms used in the Best Practice for the Management of Lymphoedema, plus expanded terms, for literature related to lymphedema. Authors sorted relevant literature for inclusion and exclusion; included articles were sorted into topical areas for data extraction and assessment of level of evidence by using a published grading system and consensus process. The authors reviewed 99 articles, of which 26 met inclusion criteria for individual studies and 1 case study did not meet strict inclusion criteria. In addition, 14 review articles and 2 consensus articles were reviewed.

Data Extraction

Information on study design and/or objectives, participants, outcomes, intervention, results, and study strengths and weaknesses was extracted from each article. Study evidence was categorized according to the Oncology Nursing Society Putting Evidence into Practice level of evidence guidelines after achieving consensus among authors.

Data Synthesis

Levels of evidence were only moderately strong, because there were few randomized controlled trials with control groups, well‐controlled interventions, and precise measurements of volume, mobility and/or function, and quality of life. Treatment interventions were often bundled, which makes it difficult to determine the contribution of each individual component of treatment to the outcomes achieved.

Conclusions

CDT is seen to be effective in reducing lymphedema. This review focuses on original research about CDT as a bundled intervention and 2 individual components, manual lymph drainage and compression bandages. Additional studies are needed to determine the value and efficacy of the other individual components of CDT.
Policy-making in an era of agencification: An exploration of task divisions between politicians, core departments and public agencies
Authors: Verschuere Bram , Vancoppenolle Diederik
Published: August 2012

In many Western countries, alongside NPM-rhetoric, important tasks of public service delivery have been devolved to autonomous single purpose agencies. This was also the case in Flanders (Belgium). This reform rhetoric also has a clear vision on how tasks in the policy cycle are to be distributed between actors: policy-making is a political prerogative, supported by core governmental departments, whereas executive agencies have policy implementation as their main task. This article addresses whether this ideal-typical model really exists, drawing on two case studies of policy initiatives in Flanders. Our observations confirm a policy-operations divide between politics and administration, but it needs refinement: ministers and their advisors make the strategic policy decisions, in which they are assisted by executive agencies. Ministerial departments are hardly involved in the policy-making process. Executive agencies are more than policy implementers alone, as they often have a large input in the operational stages of policy-making.
Do etiological influences on aggression overlap with those on rule breaking? A meta-analysis
Authors: Burt S. A.
Published: August 2012

Background

Although aggressive (AGG) and non-aggressive rule-breaking (RB) dimensions of antisocial behavior have been shown to be differentially heritable, available studies have disagreed on the extent to which the genetic and environmental factors influencing AGG also influence RB. The current meta-analysis sought to clarify the extent of etiological overlap between AGG and RB.

Method

Thirteen twin/sibling studies examining the covariation between AGG and RB were collected, of which 11 (with 12 independent samples) were ultimately included in the analyses (n=12923 twin/sibling pairs). Genetic and environmental correlations between AGG and RB served as study effect sizes. When squared, these correlations directly index the proportion of genetic and environmental overlap. Data were analyzed using mixed effect models.

Results

Analyses revealed that genetic influences on AGG were largely, but not entirely, distinct from those on RB: only 38.4% of the genetic influences on AGG overlapped with those on RB. Similarly, only 10.2% of the non-shared environmental influences on AGG overlapped with those on RB. Although the conclusion that etiological influences on AGG are partially distinct from those on RB persisted across several potential moderators, the age of the sample and the informant used were found to moderate the extent of overlap.

Conclusions

The findings underscore the presence of meaningful etiological distinctions between AGG and RB, and imply that future conceptualizations of antisocial behavior should be organized (at least in part) around the dimensions of AGG and RB.