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Nine mRNA transcripts associated with acute cellular rejection (ACR) in previous microarray studies were ported to the clinically amenable NanoString nCounter platform. Here we report the diagnostic performance of the resulting blood test to exclude ACR in heart allograft recipients: HEARTBiT.

Drosophilaintestinal tumors show an extended cellular heterogeneity. We devise a protocol to assess tumor cell heterogeneity by employing nuclear size measurement and immunofluorescence-based cell lineage analysis. We describe steps for intestinal dissection, staining, and imaging, followed by detailed procedures for nuclear size analysis. This approach efficiently detects overall heterogeneity across the entire tumor cell population and deviations within specific cell populations. The procedure is also applicable for analyzing the heterogeneity of wild-type intestinal cells in various contexts.

The article discusses the legal standards for conducting searches of students in schools. It highlights the 1985 U.S. Supreme Court case of T.L.O. v. New Jersey, which established that school officials only need reasonable suspicion, rather than probable cause, to justify a search. The article emphasizes the need to balance students' expectations of privacy with the school's need to maintain a safe learning environment. It also mentions that certain circumstances, such as imminent danger, may require immediate action without strict adherence to guidelines. Overall, the article suggests that schools should have sound policies in place to navigate search situations effectively. [Extracted from the article]

There is a direct relationship between bodyweight and risk of diabetes. Lorcaserin, a selective serotonin 2C receptor agonist that suppresses appetite, has been shown to facilitate sustained weight loss in obese or overweight patients. We aimed to evaluate the long-term effects of lorcaserin on diabetes prevention and remission.

Many tumors recapitulate the developmental and differentiation program of their tissue of origin, a basis for tumor cell heterogeneity. Although stem-cell-like tumor cells are well studied, the roles of tumor cells undergoing differentiation remain to be elucidated. We employ Drosophilagenetics to demonstrate that the differentiation program of intestinal stem cells is crucial for enabling intestinal tumors to invade and induce non-tumor-autonomous phenotypes. The differentiation program that generates absorptive cells is aberrantly recapitulated in the intestinal tumors generated by activation of the Yap1 ortholog Yorkie. Inhibiting it allows stem-cell-like tumor cells to grow but suppresses invasiveness and reshapes various phenotypes associated with cachexia-like wasting by altering the expression of tumor-derived factors. Our study provides insight into how a native differentiation program determines a tumor’s capacity to induce advanced cancer phenotypes and suggests that manipulating the differentiation programs co-opted in tumors might alleviate complications of cancer, including cachexia.

Our study elucidates the role of E-cadherin (E-cad) in cell invasion during dissemination of transformed cells from the intestine. E-cad is a new component of invasive protrusions resembling invadopodia observed in cancer cells. Notably, E-cad controls the invasiveness of transformed cells by recruiting cortactin to invasive protrusions.

Published ahead of print May 4, 2017.

One Kentucky elementary school recently had its student pickup line disrupted by the need to administer naloxone to a parent in a vehicle who had lost consciousness while waiting to pick up his child after school. The elementary school's ride pickup line can be a source of both pain and comic relief for school leaders. Organizing and managing an orderly line is a task commensurate with carrying out the D-Day invasion, and it has been the subject of numerous comedic movie scenes, social media memes and school staff meltdowns. [Extracted from the article]

Current implants for breast augmentation containing silicone gel, saline, or both can totally obscure mammographic detection of microcalcifications and soft-tissue masses. To investigate the possibility of developing a more radiolucent implant, radiographs were obtained of silicone shells that contained silicone gel, saline, silicone gel and saline, polyurethane-covered silicone gel, gelatin, sunflower oil, and peanut oil. All radiographs were obtained using a Siemens Mammomat by placing the implant over an American College of Radiology mammography phantom.

A middle school student in Florida used her cellphone video to record a school fight. This area of the law continues to develop, but the general consensus at this time is that a school resource officer's body camera footage is not subject to FERPA confidentiality requirements. [Extracted from the article]

Autologous fat grafting has been gaining popularity in recent years, although there remains concern regarding the safety and efficacy of the practice for breast surgery. The purpose of this study was to determine national trends for fat grafting to the breast and to establish the frequency and specific techniques of the procedure to provide more supportive data.

There are increasing concerns about a possible association between anaplastic large cell lymphoma (ALCL) and breast implants. The authors conducted a structured expert consultation process to evaluate the evidence for the association, its clinical significance, and a potential biological model based on their interpretation of the published evidence.

In recent years, there have been growing concerns about a possible association of non-Hodgkin's lymphoma—in particular, anaplastic large cell lymphoma (ALCL)—and breast implants. The purpose of this study was to identify and analyze all reported cases of non-Hodgkin's lymphoma occurring in patients with breast implants.

Venous thromboembolism is a devastating complication representing one of the major causes of postoperative death in plastic surgery. Within the scope of plastic surgery, body-contouring procedures are often considered to carry a higher risk of venous thromboembolism. Hereditary thrombophilias comprise a group of conditions defined by a genetic predisposition to thrombosis development. Collectively, hereditary thrombophilias are present in at least 15 percent of Western populations and underlie approximately half of thromboembolic events. Although the topic of venous thromboembolism is discussed widely throughout the literature, there is little published on the diagnosis and management of hereditary thrombophilias in the plastic surgery literature. The goals of this study were to present a review of the major inherited thrombophilias, to delineate the risk of these disorders, and to recommend a practical algorithm for patient screening and management before major plastic surgery.

Few data are available regarding the psychological impact of scars arising from routine elective/aesthetic surgical procedures. To gain insight into both patients’ and clinicians’ concerns, the authors have undertaken structured semiquantitative surveys of (1) patients who had recently undergone a routine surgical procedure and (2) a cohort of plastic and aesthetic dermatological surgeons.

Campylobacter jejuni is a globally distributed cause of human food-borne enteritis and has been linked to chronic joint and neurological diseases. We hypothesized that C. jejuni 11168 colonizes the gastrointestinal tract of both C57BL/6 mice and congenic C57BL/6 interleukin-10-deficient (IL-10–/–) mice and that C57BL/6 IL-10–/–mice experience C. jejuni 11168-mediated clinical signs and pathology. Individually housed mice were challenged orally with C. jejuni 11168, and the course of infection was monitored by clinical examination, bacterial culture, C. jejuni-specific PCR, gross pathology, histopathology, immunohistochemistry, and anti-C. jejuni-specific serology. Ceca of C. jejuni 11168-infected mice were colonized at high rates: ceca of 50/50 wild-type mice and 168/170 IL-10–/–mice were colonized. In a range from 2 to 35 days after infection with C. jejuni 11168, C57BL/6 IL-10–/–mice developed severe typhlocolitis best evaluated at the ileocecocolic junction. Rates of colonization and enteritis did not differ between male and female mice. A dose-response experiment showed that as little as 106CFU produced significant disease and pathological lesions similar to responses seen in humans. Immunohistochemical staining demonstrated C. jejuni antigens within gastrointestinal tissues of infected mice. Significant anti-C. jejuni plasma immunoglobulin levels developed by day 28 after infection in both wild-type and IL-10-deficient animals; antibodies were predominantly T-helper-cell 1 (Th1)-associated subtypes. These results indicate that the colonization of the mouse gastrointestinal tract by C. jejuni 11168 is necessary but not sufficient for the development of enteritis and that C57BL/6 IL-10–/–mice can serve as models for the study of C. jejuni enteritis in humans.

ABSTRACTCampylobacter jejuniis a globally distributed cause of human food-borne enteritis and has been linked to chronic joint and neurological diseases. We hypothesized that C. jejuni11168 colonizes the gastrointestinal tract of both C57BL/6 mice and congenic C57BL/6 interleukin-10-deficient (IL-10−/−) mice and that C57BL/6 IL-10−/−mice experience C. jejuni11168-mediated clinical signs and pathology. Individually housed mice were challenged orally with C. jejuni11168, and the course of infection was monitored by clinical examination, bacterial culture, C. jejuni-specific PCR, gross pathology, histopathology, immunohistochemistry, and anti-C. jejuni-specific serology. Ceca of C. jejuni11168-infected mice were colonized at high rates: ceca of 50/50 wild-type mice and 168/170 IL-10−/−mice were colonized. In a range from 2 to 35 days after infection with C. jejuni11168, C57BL/6 IL-10−/−mice developed severe typhlocolitis best evaluated at the ileocecocolic junction. Rates of colonization and enteritis did not differ between male and female mice. A dose-response experiment showed that as little as 106CFU produced significant disease and pathological lesions similar to responses seen in humans. Immunohistochemical staining demonstrated C. jejuniantigens within gastrointestinal tissues of infected mice. Significant anti-C. jejuniplasma immunoglobulin levels developed by day 28 after infection in both wild-type and IL-10-deficient animals; antibodies were predominantly T-helper-cell 1 (Th1)-associated subtypes. These results indicate that the colonization of the mouse gastrointestinal tract by C. jejuni11168 is necessary but not sufficient for the development of enteritis and that C57BL/6 IL-10−/−mice can serve as models for the study of C. jejunienteritis in humans.

Frontline LEGAL BRIEF A SCHOOL DISTRICT in our state was preparingto vote on a tax levy. On the day the board of education plannedto formally approve the levy and put it up forpublic approval, one board member had to behospitalized with a serious illness. Open Meetings Laws The most likely source of guidance for remoteelectronic participation by school board membersis the state's open meeting law (or "sunshine"laws). [Extracted from the article]

Protonation of (2-(dimethylamino)ethyl)cyclopentadienyl (Cp^N) group VI metal carbonyl anions with acetic acid proceeds at the amine to provide zwitterionic (2-(dimethylammonium)ethyl)cyclopentadienyltricarbonylmetalates, M(CO)3(η⁵-Cp^NH) (M = Cr (1), Mo (2), W (3)). Few zwitterionic organometalates with anionic metal centers and positive charges that cannot be delocalized have been reported to date. The impact of the intramolecular charge separation on the structures and reactivity of zwitterionic organometalates is of current interest. The M(CO)3 units of structurally characterized 1−3 are significantly perturbed in solution and the solid state due to ion-pairing between the pendant ammonium cation and anionic metal center. The concentration and solvent dependence of the ¹H NMR ammonium hydrogen chemical shifts of 1−3 and the intramolecular N···M separations of these zwitterions in the solid state are consistent with three-center−four-electron N−H···M hydrogen bonding. One other hydrogen bond with a zerovalent group VI metal acceptor has been characterized to date. The intramolecular charge separation attenuates the reactivity of the anionic metal centers of 1−3 relative to that of [M(CO)3(η⁵-Cp)]^-. Structurally characterized [WH(CO)3(η⁵-Cp^NH)]Cl (4) was the only isolable salt obtained from protonation of 1−3; the Cr and Mo analogues are unstable relative to 1 and 2, respectively. Structurally characterized [M(AuPPh3)(CO)3(η⁵-Cp^NH)]Cl (M = Mo (5), W(6)) were synthesized via reactions of 2 and 3, respectively, with Ph3PAuCl and protonation of M(AuPPh3)(CO)3(η⁵-Cp^N) (M = Mo (8), W (9)) with HCl. Pure samples of the analogous chromium salt were inaccessible from either 1 or structurally characterized Cr(AuPPh3)(CO)3(η⁵-Cp^N) (7).

Crystal structures of glyme solvates with LiTFSI and LiBETI (TFSI^- = bis(trifluoromethanesulfonyl)imide, BETI^- = bis(perfluoroethanesulfonyl)imide) have been determined including (monoglyme)1:LiBETI, (diglyme)2:LiTFSI, (diglyme)1/2:LiTFSI, and low-temperature (triglyme)1:LiBETI. These solvates, combined with the phase behavior of the salts with various glymes from DSC analysis, provide insight into the molecular interactions of lithium salts in ethoxy solvents commonly used for solid polymer and liquid electrolytes. Many of the solvates appear to undergo order−disorder solid phase transitions. These are the first reported crystal structures containing the BETI^- anion.

Salts of (2-(dimethylamino)ethyl)cyclopentadienyl (Cp^N) group VI metal carbonyl anions ([M(CO)3(η⁵-Cp^N)]^- (M = Cr, Mo, W)), important reagents for studies involving Cp^N, have been characterized by X-ray crystallography. These anions (M‘ = Mo, W) react with R3SnCl (R = Ph, cyclohexyl) to provide structurally characterized tin(IV) derivatives.

A means to induce dehydrodimerization of Seebach's oxazolidinone (5), the stereochemical outcome of which is entirely temperature dependent, is described. The resultant dimers 3 and 4 are precursors to (R,R)-α,α‘-biproline (1) and meso-α,α‘-biproline (2), respectively. An organohypobromite and an iminium halide are proposed to serve as electrophiles in the reaction with the enolate of 5 to give 3 and 4, respectively.

Two new isostructural scandium and indium phosphate frameworks, (C6H14N2)M4F2(PO4)4·4H2O (M = Sc, In), have been synthesized from hydrothermal conditions using an organic amine, 1,4-diazabicyclo[2.2.2]octane (DABCO), as a template. Their structures have been determined by single-crystal X-ray diffraction and supported by solid-state magic-angle spinning (MAS) NMR spectroscopy. They crystallize in the P21/n space group with a = 10.283(2) Å, b = 12.698(2) Å, c = 17.864(3) Å, and β = 102.761(3)° and a = 10.280(2) Å, b = 12.700(2) Å, c = 17.860(4) Å, and β = 102.47(3)° for Sc- and In-compounds, respectively. They are built from corner-sharing M octahedra and P tetrahedra which form eight- and six-membered channels along the b-axis. The channels are occupied by organic templates and water molecules. All PO4 groups share four corners with M polyhedra, resulting in a fully connected framework. The local environments around P, F, and Sc atoms in the Sc-compound were carefully examined by ³¹P MAS, ¹⁹F MAS, ⁴⁵Sc MAS, ⁴⁵Sc MQMAS, and ⁴⁵Sc/¹⁹F REDOR NMR spectroscopy.

Prophylactic bilateral mastectomy has been demonstrated to reduce breast cancer incidence in women with a high inherited susceptibility to breast cancer. For the majority of high-risk women, however, bilateral prophylactic mastectomy is not an acceptable option for primary prevention of breast cancer. Several epidemiological follow-up studies have indicated that there may be a substantial reduction in breast cancer risk among women who have undergone breast reduction surgery. The authors reviewed the evidence from these studies, with emphasis on the problems inherent in interpreting the results of nonexperimental studies of elective medical procedures. Although such observational studies cannot demonstrate definitively that reduction mammaplasty reduces the risk of breast cancer, the evidence from these studies is sufficiently strong to warrant the evaluation of breast reduction surgery as an option for primary prevention in clinical studies of women at increased risk of breast cancer. The availability of a more acceptable surgical option for primary prevention of breast cancer could increase the number of women willing to choose risk reduction surgery and thus may result in an overall reduction in breast cancer mortality among high-risk women.

Low-level laser therapy is a new subspecialty for the medical application of lasers that provides therapeutic rather than surgical outcomes for many medical indications. Recently, low-level laser therapy was reported to “liquefy” or release stored fat in adipocytes by the opening of specialized yet not identified cell membrane–associated pores after a brief treatment. Currently, low-level laser therapy is a U.S. Food and Drug Administration–approved technology for improving pain alleviation. To explore these data further, a series of in vitro studies on human preadipocytes and institutional animal care and use committee–approved protocols in a porcine Yucatan model and an institutional review board–approved clinical study were performed. Using a 635-nm low-level laser of 1.0 J/cm2supplied to the authors by the vendor, these studies were designed to determine whether alteration in adipocyte structure or function was modulated after low-level laser therapy. Cultured human preadipocytes after 60 minutes of laser therapy did not change appearance compared with nonirradiated control cells. In the porcine model, low-level laser therapy (30 minutes) was compared with traditional lipoplasty (suction-assisted lipoplasty) and ultrasound-assisted lipoplasty. From histologic and scanning electron microscopic evaluations of the lipoaspirates, no differences were observed between low-level laser therapy–derived and suction-assisted lipoplasty–derived specimens. Using exposure times of 0, 15, 30, and 60 minutes in the presence or absence of superwet wetting solution and in the absence of lipoplasty, total energy values of 0.9 mW were delivered to tissue samples at three increasing depths from each experimental site. No histologic tissue changes or specifically in adipocyte structure were observed at any depth with the longest low-level laser therapy (60 minutes with superwet fluid). Three subjects undergoing large-volume lipoplasty were exposed to superwet wetting fluid infiltration 14 minutes before and 12 minutes after, according to vendor instructions. Tissue samples from infiltrated areas were collected before suction-assisted lipoplasty and lipoaspirates from suction-assisted lipoplasty. No consistent observations of adipocyte disruptions were observed in the histologic or scanning electron microscopy photographs. These data do not support the belief that low-level laser therapy treatment before lipoplasty procedures disrupts tissue adipocyte structure.

The compound [Ph2N3C2(C3F7)2]HgCH3 was synthesized from Na[Ph2N3C2(C3F7)2] and CH3HgCl. In solution, it exists as a mixture of two isomers that interconvert slowly on the NMR time scale. Both isomers feature a η¹-Ph2N3C2(C3F7)2 ligand. In the asymmetrical one, the CH3Hg group is bonded to one of the two terminal nitrogen atoms. In the more stable symmetrical isomer, [PhN&dbd;C(C3F7)]2NHgCH3, mercury is attached to the central nitrogen atom. It is this isomer that crystallizes and that was characterized by X-ray diffraction. Thermodynamic parameters for the CH3Hg shift reaction were obtained by DNMR spectroscopy. ¹⁹F NMR spectra were analyzed. A metallotropic rearrangement was not observed in [Ph2N3C2(C3F7)2]AuPPh3.

Reactions of aqueous base with the dicationic iridium and rhodium thiophene complexes [Cp*Ir(η⁵-2,5-Me2T)](X)2 (X = BF4, 1(BF4); X = OSO2CF3, 1(OTf)) and [Cp*Rh(η⁵-2,5-Me2T)](BF4)2 (8(BF4)) and the acid/base reactivity of these products are discussed. The reaction of 1(BF4) with 1 equiv of aqueous KOH (0.01 M) affords the following mixture of mono-, di-, and tetranuclear compounds:  [Cp*Ir(η⁴-SC(Me)CHCHC(O)Me)] (3), (Cp*Ir)[Cp*Ir(η⁴-SC(Me)CHCHC(O)Me)]3(BF4)2 (4(BF4)), [(Cp*Ir)2(μ2,η⁴-SC(Me)CHCC(O)Me)](BF4) (5(BF4)), and [Cp*Ir(μ2,η³-SC(Me)CHCH2C(O)Me)]2(BF4)2 (6(BF4)). The ¹H and ¹³C NMR data are consistent with the single-crystal X-ray diffraction structures of the cationic complexes 4(BF4), 5(OTf), and 6(BF4). These products are formed by a complex series of reactions that begin with the displacement of the 2,5-dimethylthiophene (2,5-Me2T) ligand from 1 and reaction of the resulting “[Cp*Ir]²⁺” fragment with 3. In the synthesis of 8(BF4), the new complex [(Cp*Rh)2(μ2,η⁴-SC(Me)CHCC(O)Me)](BF4) (9(BF4)), analogous to 5(BF4), is produced. Studies of the reactions of [Cp*Rh(η⁵-2,5-Me2T)](BF4)2 (8(BF4)) with OH^- and MeO^- show a type of reactivity quite different from that observed for 1(BF4) and 1(OTf). The solvolysis of 8(BF4) in acetone affords the mononuclear complex [Cp*Rh(OCMe2)2(OH)](BF4) (10(BF4)), whose crystal structure is described. Detailed NMR studies establish the pathways by which [Cp*Ir(η⁵-2,5-Me2T)]²⁺ (1) and [Cp*Rh(η⁵-2,5-Me2T)]²⁺ (8) react with H2O/OH^- and MeOH/MeO^- to give the variety of observed products.

Three crystal structures of tetraglyme coordination complexes with lithium salts are reported&sbd;(tetraglyme)1:LiAsF6, (tetraglyme)1/2:LiBF4, and (tetraglyme)2/5:LiCF3CO2. A novel form of six-coordinate Li⁺ cation coordination by the ether oxygens is found resembling double-helix dimers. Structural characterization of these materials provides insight into the molecular interactions which occur among the cations, anions, and ether oxygens. Such interactions are of interest for aiding in the understanding of the many factors which contribute to ionic conductivity mechanisms in amorphous concentrated liquid and solid poly(ethylene oxide) electrolytes.

Crystalline phases of (triglyme)1:LiX (X = CF3SO3^-, BF4^-, ClO4^-, and AsF6^-) have been isolated and structurally characterized. The phases are isostructural and represent a novel form of Li⁺ cation coordination not observed in crystalline poly(ethylene oxide) (PEO)−salt phases. The crystal structure of a (triglyme)1:LiBPh4 phase has also been determined, which differs markedly from those found with the smaller anions. In addition, a more concentrated (triglyme)2/3:LiCF3SO3 phase has been characterized, which also displays a novel form of Li⁺ cation coordination. Such solvates represent models for interchain cation transport transition states in concentrated liquid and amorphous PEO electrolytes.

The reaction of TlTp‘ (Tp‘ = HB(3-mesitylpyrazolyl)3^- (Tp^Ms), HB(3-mesitylpyrazolyl)2(5-mesitylpyrazolyl)^- (Tp^Ms*)) with NiCl2·6H2O affords Tp^MsNiCl (1) and Tp^Ms*NiCl (2) in good yield. The compound 2 undergoes an isomerization process to form [{Tp^Ms**}NiCl]2 (3) (Tp^Ms**= HB(5-mesitylpyrazolyl)2(3-mesitylpyrazolyl)^-) in 68% yield. Treatment of the tris(pyrazolyl)borate nickel compounds 1 and 2 with alkylaluminum cocatalysts such as methylalumoxane (MAO) and trimethylaluminum (TMA) in toluene generates active catalysts for ethylene oligomerization. The compound 1 shows turnover frequencies in the range of (2.2−43.1) × 10³ h^-1. Oligomerization reaction conditions can be adjusted that lead to selectivities as high as 81% for butene-1.

The recent expansion of zeolitic synthesis toward mixed geometry frameworks reflects their potential applications in shape-selective catalysis and absorption. Four scandium phosphates with three-dimensional frameworks have been hydrothermally synthesized. All structures were solved from single-crystal X-ray diffraction and were supported by ³¹P MAS NMR and infrared spectroscopy. Structure 1 ((C2N2H10)8Sc8(ScO2)4(PO4)4(HPO4)12·12H2O) consists of a novel framework with 14-membered rings (MRs) and 10-MR channels along the a and c axes, respectively. Ethylenediamine and water reside in the resulting supercage. Structure 2 ((C2N2H10)2Sc4(HPO4)8) consists of a framework built from the corner-sharing of ScO6 octahedra with HPO4 tetrahedra whose connection results in a 8-MR channel down the a axis, where hydrolyzed cyclam resides. This compound is isostructural to a number of existing synthetic materials including a scandium phosphate, an indium phosphate, and an iron phosphate. Structure 3 (Sc4(HPO4)8·4(H3O)) is a framework built in the same way as structure 2 but is described by a 12-MR channel down the a axis in which hydronium resides. This structure is isostructural to a ferric oxonium bis(hydrogenphosphate). Structure 4 (Sc4(PO4)4·8H2O) is a framework built by the corner-sharing of PO4 tetrahedra with ScO4·2H2O octahedra to form 8-MR channels down the a-axis. This structure occurs in nature as sterrettite, a scandium-bearing phosphate mineral, and has an isostructural indium phosphate. Crystal data:  structure 1, P21/n, a = 8.603(2) Å, b = 15.476(3) Å, 16.504(4) Å, and β = 96.877(5)°, structure refinement converged at R = 0.0443; structure 2, P2/n, a = 9.4111(15) Å, b = 9.1066(15) Å, c = 9.6950(15) Å, and β = 117.272(3)°, structure refinement converged at R = 0.032; structure 3, P2/n, a = 5.3048(11) Å, b = 8.8230(18) Å, c = 14.779(3) Å, and β = 96.685(5)°, structure refinement converged at R = 0.0433; structure 4, P2(1)/n, a = 5.4429(8) Å, b = 10.2513(15) Å, c = 8.9094(11) Å, and β = 90.253(7)°, structure refinement converged at R = 0.063.

This study analyzed the shells of single-lumen silicone gel breast implants within the general context of device durability in vivo. The investigation included the major types of gel-filled implants that were manufactured in the United States in a 30-year period. The implants analyzed were Cronin seamed (two explants and one control), Silastic 0 and Silastic I (18 explants and seven controls), and Silastic II (22 explants and 43 controls). The biodurability of the explants was investigated with measurements of the mechanical and chemical properties of the various types of silicone gel control and explanted shells, with implantation times ranging from 3 months to 32 years. The shell properties measured for the controls and explants included the stress-strain relationships, tensile strength, elongation, tear resistance, moduli, cross-link density, and amount of extractable material in the shell. In addition, the mechanical properties of shells that had been extracted with hexane were analyzed for both explants and control implants. The silicone gel explants investigated in this study included some of the oldest explants of the various major types that have been tested to date. For assessment of long-term implantation effects, the data obtained in this study were combined with all known data from other institutions on the various major types of gel implants. The study also addressed the failure mechanisms associated with silicone gel breast implants. The results of the study demonstrated that silicone gel implants have remained intact for 32 years in vivo and that degradation of the shell mechanical and chemical properties is not a primary mechanism for silicone gel breast implant failure.

New N-functionalized benziodazoles were prepared by the peracetic oxidation of 2-iodobenzamides derived from alanine or valine. X-ray crystal structural analysis of two benziodazole-based phenyliodonium derivatives provides insight into facile interchange between benziodazoles and iminium benziodoxoles under acidic or basic conditions.

Emissions of volatile chemicals control the hydroxyl radical (OH), the atmosphere's main cleansing agent, and thus the production of secondary pollutants. Accounting for all of these chemicals can be difficult, especially in environments with mixed urban and forest emissions. The first direct measurements of the atmospheric OH reactivity, the inverse of the OH lifetime, were made as part of the Southern Oxidant Study (SOS) at Cornelia Fort Airpark in Nashville, TN in summer 1999. Measured OH reactivity was typically 11 s−1. Measured OH reactivity was 1.4 times larger than OH reactivity calculated from the sum of the products of measured chemical concentrations and their OH reaction rate coefficients. This difference is statistically significant at the 1σ uncertainty level of both the measurements and the calculations but not the 2σ uncertainty level. Measured OH reactivity was 1.3 times larger than the OH reactivity from a model that uses measured ambient concentrations of volatile organic compounds (VOCs), NO, NO₂, SO₂, and CO. However, it was within ~10% of the OH reactivity from a model that includes hydrocarbon measurements made in a Nashville tunnel and scaled to the ambient CO at Cornelia Fort Airpark. These comparisons indicate that 30% of the OH reactivity in Nashville may come from short-lived highly reactive VOCs that are not usually measured in field intensive studies or by US EPA's Photochemical Assessment Monitoring Stations.

The iridathiabenzene analogues [η⁶-Cp*Ir(C,S-2,5-Me2T)]M(CO)3, where M = Cr (3), Mo (5), W (7), of (η⁶-arene)M(CO)3 are prepared from M(CO)3(NCMe)3 and Cp*Ir(C,S-2,5-Me2T) (2), where C,S-2,5-Me2T is ring-opened 2,5-dimethylthiophene. The high reactivity and coordination flexibility of the η⁶-Cp*Ir(C,S-2,5-Me2T) ligand leads to a variety of products upon reaction with phosphine ligands. The reaction of 3 with PEt3 leads to PEt3 adduct formation at the Ir in the product [η⁵-Cp*Ir(PEt3)(C,S-2,5-Me2T)][Cr(CO)3] (17). On the other hand, reaction of the analogous tungsten complex 7 with PEt3 yields the adduct [η⁴-Cp*Ir(C,S-2,5-Me2T)]W(CO)2(PEt3)(μ-CO) (19), in which PEt3 adds to the W atom. These and other studies show that the iridathiabenzene ligand is capable of coordination to Cr, Mo, or W through one, four, five, or six of its ring atoms. When 7 is reacted with CF3SO3H, protonation occurs at the tungsten, as occurs in the protonation of the analogous arene complex (η⁶-C6Me6)W(CO)3. Structures of four of the complexes were established by X-ray studies.

Several generations of silicone gel breast implants have been produced by implant manufacturers. The primary material usually viewed as the base material in the manufacture of implants is polydimethylsiloxane. Polymeric reactions are notorious for their variability and nonuniformity. The elastomer used in different types of implants can have vastly different properties. Furthermore, the material properties associated with a particular type of implant can vary considerably from one lot to the next. Considering the various designs, styles, and manufacturing techniques associated with silicone gel implants, knowledge of the original properties of the implants before implantation is important in determining the effects of aging in vivo. This study was conducted to investigate differences in key mechanical and chemical properties of silicone gel breast implant materials. The two types of implants chosen for analysis were Silastic I and Silastic II control implants. Material property data were determined for both types of controls and significant differences were found in their values. Lottolot variability was also investigated and found to be significant. Plast. Reconstr. Surg.108 647, 2001.

This article summarizes the current state and future needs of research into saline-filled and silicone gel breast implants. The authors describe recent investigations into possible causes and potential risk factors for silicone gel and saline implant failure. Also discussed are local complications of breast implantation and the need for revisional operations in augmentation and reconstruction patients. In addition, the effects that surgical, implant, and patient variables have on the aesthetic outcome of surgery are addressed. The last portion of the article lays out future research needs, such as determining the incidence rate of implant failure, reducing the frequency of revisional surgery, and the difficulty of designing better breast implants in the current strict regulatory climate.

In this article, mechanisms of breastimplant failure caused by surgical instruments commonly used to perform implantation, breast biopsies, needle localization procedures, cyst aspirations, and explantation are described. Failure was artificially induced in breastimplant shells using various types of surgical instruments, including scalpels, suture needles, hypodermic needles, hemostats, and Adson forceps. Fieldemission scanning electron microscopy SEM was used to document the morphology of the failure sites produced by these instruments. Micrographs were used to categorize failure according to a specific type of surgical instrument. SEM micrographs were also obtained on explants that failed in situ, and the morphology of the corresponding failure sites was examined. The study was designed to document a range of failure mechanisms associated with gelfilled, salinefilled, doublelumen salinegel, and soybean oilfilled implants. The results of the study also demonstrate that SEM can often be used to determine the cause of breastimplant failure. Plast. Reconstr. Surg.108 52, 2001.

X-ray structural studies establish that the titanium dicarbollide complexes (η⁵-C2B9H11)(C5Me5)TiMe (4) and (η⁵-C2B9H11)(η⁵,η¹-C5Me4CH2)Ti (5) adopt bent metallocene structures. In 4 the metallocene units are linked into chains by weak intermolecular Ti- - -H−B interactions involving B−H units that are meta to Ti within the C2B9Ti cages. The fulvene ligand in 5 is bonded in a π-η⁵,σ-η¹-fashion.

Continued investigation of cancer-cell growth-inhibitory constituents of the blue marine sponge Cribrochalina sp. has led to discovery of cribrostatins 3 (4a), 4 (5), and 5 (4b) in 10^-5 to 10^-7 % of the wet weight. The structure of cribrostatin 3 (4a) was determined by results of high field (500 MHz) ¹H and ¹³C NMR and HRMS interpretations. The same general approach to the structures of cribrostatins 4 (5) and 5 (4b) was completed by X-ray crystal structure determinations. Cribrostatins 3, 4, and 5 provided significant cancer cell line inhibitory activities. Cribrostatins 1 and 2² and the newly isolated cribrostatins 3−5 displayed antibacterial and/or antifungal activities.