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Carbapenems can be an effective treatment of infections with multidrug-resistant Gram-negative bacteria such as Pseudomonas aeruginosa,1 Acinetobacter spp.,2 Klebsiella pneumoniae,3 and other Enterobacteriaceae.4 They are semi-synthetic or synthetic β-lactam compounds that are distinguished from other β-lactam compounds such as penicillins and cephalosporins by the absence of a sulfur atom in the bicyclic core and a different stereochemistry at Cα of the β-lactam ring (in penicillins and carbapenems, this atom is usually referred to as C6; in cephalosporins as C7) (Figure 1). The most popular carbapenem antibiotics are imipenem5, 6 (Merck, 1985), meropenem7, 8 (Sumitomo Pharmaceuticals and AstraZeneca, 1996), ertapenem9, 10 (Merck, 2005), and doripenem11, 12 (Shionogi Co. and Johnson & Johnson, 2005) (Figure 2). All of these broad-spectrum drugs are used intravenously. Carbapenems are considered to be drugs of last resort due to the fact that they are not inactivated by and effectively inhibit many β-lactamases (most Ambler class A and C β-lactamases13), while these enzymes efficiently hydrolyze penicillins and cephalosporins. β-Lactamases hydrolyze the β-lactam ring of β-lactam antibiotics blocking peptidyltransferase (also referred to as penicillin binding protein or PBP) activity that is critical for the peptidoglycan biosynthesis of the bacterial cell wall.14 β-Lactam antibiotics inhibit peptidyltransferase by forming a stable acyl-enzyme intermediate after an active-site serine of pepdityltransferase cleaves the β-lactam ring through a nucleophilic attack.15 Similar to peptidyltransferase, most β-lactamases contain an active site serine, which exerts a nucleophilic attack on and cleaves the β-lactam ring, resulting in turnover by the enzyme. These enzymes are referred to as serine β-lactamases (SBLs) and, based on sequence and structural homology, have been grouped into classes A, C, and D by Ambler.13 CTX-M β-lactamases are a group of class A SBLs expressed by Enterobacteriaceae that confer resistance toward the third-generation cephalosporin cefotaxime (Figure 3).16 As a consequence, carbapenems are frequently used to treat infections with Enterobacteriaceae expressing these enzymes. The increased use of carbapenems drives the emergence of carbapenem resistance mechanisms. Open in a separate window Figure 1 Chemical structures of the bicyclic cores of different classes of β-lactam antibiotics. The penem core is found in penicillins and consists of a β-lactam ring fused with a tetrahydrodrothiazole ring. The cephem core is found in cephalosporins and consists of a β-lactam ring fused with a dihydrothiazine ring. The carbapenem core consists of a β-lactam ring fused with a dihydropyrrole ring. Heavy atoms of the bicyclic systems are numbered according to common use rather than according to the IUPAC nomenclature to facilitate comparisons between the different antibiotics. Note that the numbering of the R groups is arbitrary; here we started labeling R groups from the ones attached to the core atoms with the lowest number. more...

Three case studies involving scientists from different disciplines that contribute their expertise to advancing human rights in the US and abroad are discussed. Scientific research can have a greater impact on society if directed towards solving problems relevant to human rights. Progress in science and technology can be abused, leading to violations of human rights, but can also benefit humanity. Scientists have an opportunity to play an active role in preserving human rights. more...

This study reports the actual laboratory-tested total fat amounts and portion sizes of food samples taken from four New Jersey public middle-school cafeterias. It is based on the hypothesis that the actual total dietary fat of foods served by schools can vary from published school foodservice administration expectations and surveyed findings in the literature. Seventy-two individual food samples were taken from middle school cafeterias. Total fat analysis was done using a standard Association of Official Agricultural Chemists method. Portion size and total fat values were compared with listed amounts in school foodservice records. With the exception of certain menu items with significantly higher than total fat listed, the average total fat across the schools was generally close to values reported by the schools. Average portion sizes were more problematic and overall, generally higher than documented values. Concerns with respect to portion size and total fat consistency were revealed. more...

This investigation follows seminal work on nutrient degradation as the authors seek to quantify how much vitamin C, as a marker of nutrient quality, is retained at various stages of processing (frozen, steamed, trayline and delivery) of peas at two New Jersey hospitals. Healthcare providers use nutrient data standards provided by various national and international government and nongovernment agencies. Physicians, dietitians and menu planners rely on these values for nutritional therapy. We found that the current methodology for predicting nutritional outcomes of cooked foods in hospitals may not be reliable in assessing nutrients served to patients. Sampled peas were found to contain significantly ( P < 0.05 for both Hospitals A and B) less vitamin C compared with the published standard value (‘cooked’) for vitamin C. In Hospitals A and B, the nutrient quality of vitamin C was significantly reduced ( P < 0.05) as peas progressed to patients. As improved nutritional status has been shown to correlate with faster healing and recovery, thus reduced hospital stays, we recommend that hospitals use improved cooking methods to reduce the loss of nutrients in foods served to patients. Vegetables in particular should be cooked for the briefest period of time or at the lowest temperature that ensures safety. more...

We describe a novel, "mix and read" immunoassay for insulin in biological samples using FMAT. Current commercial assays for insulin require multiple washing steps and can be expensive. The insulin assay described is a simple two-step, time-saving assay and amenable to robotics. The linear response for the fluorometric signal is comparable to that observed using classical ELISA and RIA. A series of mouse plasma samples were tested for insulin levels and yielded results comparable to that measured using a commercial ELISA for insulin. more...

IMP-1 metallo-beta-lactamase (class B) is a plasmid-borne zinc metalloenzyme that efficiently hydrolyzes beta-lactam antibiotics, including carbapenems, rendering them ineffective. Because IMP-1 has been found in several clinically important carbapenem-resistant pathogens, there is a need for inhibitors of this enzyme that could protect broad spectrum antibiotics such as imipenem from hydrolysis and thus extend their utility. We have identified a series of 2,3-(S,S)-disubstituted succinic acids that are potent inhibitors of IMP-1. Determination of high resolution crystal structures and molecular modeling of succinic acid inhibitor complexes with IMP-1 has allowed an understanding of the potency, stereochemistry, and structure-activity relationships of these inhibitors. more...

Peptide deformylase is an essential eubacterial metalloenzyme involved in the maturation of proteins by cleaving the N-formyl group from N-blocked methionine polypeptides. Biaryl acid analogs containing tetrazole, acyl sulfonamide, or carboxylate pharmacophores were found to be potent inhibitors of recombinant Escherichia coli peptide deformylase. Two of these compounds, a biphenyl tetrazole, compound 1, and a biphenyl acyl sulfonamide, compound 4, were competitive inhibitors with Ki values of 1.2 and 6.0 μM, respectively. By analogy to the binding of related compounds to other metalloenzymes such as Bacteroides fragilis metallo-β-lactamase CcrA and human carbonic anhydrase, a mechanism of inhibition is proposed for these peptide deformylase inhibitors where the acidic moieties form direct ionic interactions with the active site metal cation. more...

Resistance to carbapenem antibiotics in gram-negative bacteria is due, in part, to expression of a wide spectrum metallo-beta-lactamase, which renders the drug inactive. Biphenyl tetrazoles containing 3-n-butyl-1-phenylpyrazole-5-carboxylates or the corresponding 5-ethyl esters were found to inhibit metallo-beta-lactamases as well as renal dehydropeptidase I to a lesser extent. more...

As part of a structure-aided effort to design clinically useful inhibitors of metallo-beta-lactamases, the X-ray crystal structure of a complex between the metallo-beta-lactamase from Bacteroides fragilis and 4-morpholinoethanesulfonic acid (MES) has been determined and a model for the structure has been refined to a crystallographic R-factor of 0.151 for data between 10.0- and 1.85-A resolution. Although the binding of MES was an adventitious result of the use of MES as a buffer in the crystallization mixture, MES was subsequently shown to be a competitive inhibitor of the enzyme, with a Ki of 23 +/- 5 mM. MES binds in the same fashion to both of the molecules in the crystallographic asymmetric unit; both direct and solvent-mediated hydrogen bonds to the protein and to the binuclear zinc cluster are observed, involving the oxygens of the sulfonic acid group and the nitrogen of the morpholino ring. In addition, there are hydrophobic interactions between the morpholino ring and residues in the flexible beta-strand of the enzyme between residues 26 and 36. Comparison of this structure with the previously reported unliganded structures of the same enzyme [Concha, N. O., Rasmussen, B. A., Bush, K., and Herzberg, O. (1996) Structure 4, 823-836; Carfi, A., Duée, E., Paul-Soto, R., Galleni, M., Frère, J. -M., and Dideberg, O. (1998) Acta Crystallogr. D54, 47-57] reveals that although the overall conservation of structure in the three different crystal lattices is very high, binding of MES is correlated with a significant change in the conformation of this beta-strand. The flexibility of this beta-strand will be an important consideration in the design of inhibitors of the metallo-beta-lactamases. more...

Xylella fastidiosa (Xf) is the causative agent of Pierce's disease in a variety of commercially important plants such as citrus, coffee, and grapes. By blocking the xylem, Xf disrupts water and nutrient transport. Xf is a gram-negative phytopathogen that can form biofilms. Twelve genes have been identified in Xf that can regulate exopolysaccharides, a major component of biofilms, including aconitase, which responds to intracellular iron levels. We have employed a quantitative assay for biofilm formation referred to as minimal biofilm elimination concentration (MBEC) assay that is amenable for highthroughput screening. Biofilm formation by Xf (Napa, CA) can be blocked using iron chelators such as lactoferrin (LF), ethylenediaminetetraacetic acid (EDTA), and S, S' ethylenediaminedisuccinic acid (EDDS). Incubation of Xf in the presence of LF at 1000 μg/mL for 3.5 days showed inhibition of biofilm formation (42%) as well as inhibition (32%) of planktonic growth (liquid-phase bacteria). EDTA at a concentration of 15 mg/mL inhibited 99.7% of biofilm formation and 98.9% of planktonic growth in a 24 h incubation. In contrast, EDDS at a concentration of 38.2 mg/mL showed 64.7% inhibition of biofilm formation and 33.6% inhibition of planktonic growth. Iron deprivation could serve as a first step toward eradication of Pierce's disease via blockage of biofilm formation. more...

The gene from Bacteroides fragilis encoding a metallo-beta-lactamase, ccrA, was expressed in Escherichia coli BL21(DE3) containing the wild-type disulfide bond-catalyzing system dsb as an active, soluble enzyme in quantities exceeding 100 mg/liter using both rich and minimal media. Both the nonfusion and a glutathione S-transferase fusion enzyme lacking the periplasmic signal sequence were purified to homogeneity. Characteristics of the purified nonfusion enzyme are shown to be similar to those of the renatured enzyme previously reported. Thermal denaturation studies using circular dichroism and fluorescence spectroscopy show that CcrA undergoes a transition at approximately 50 degrees C which corresponds to the transition temperature of catalytic activity. The secondary structure of the protein and the catalytic apparatus are thus intimately linked. more...

4-Aza-5alpha-androstan-3-one 17beta-(N-substituted carboxamides) are potent human type 2 5alpha-reductase (5aR) inhibitors with generally poor binding to the human androgen receptor (hAR). When the 17-amide N-substituent included an aromatic residue, potent dual inhibitors of both type 1 and 2 5aR are produced, but hAR binding remained poor. Tertiary-substituted-17-amides have reduced inhibition of both 5aR isozymes. The addition of an N4-methyl substitutent to the A-ring profoundly increased hAR affinity and the addition of unsaturation to the A-ring (delta1) modestly augmented hAR binding. The unsubstituted carbanilides in the delta1-N4-methyl series show some selectivity for type 1 5aR over the type 2 isozyme, whereas addition of aryl substituents, particularly at the 2-position, increased type 2 5aR binding to provide dual inhibitors with excellent hAR binding, e.g. N-(2-chlorophenyl)-3-oxo-4-methyl-4-aza-5alpha-androst-1-ene-17bet a-carboxamide (9c). Compounds of this type exhibit low nanomolar IC50s for both human 5aR isozymes as well as the human androgen receptor. Kinetic analysis confirms that the prototype 9c displays reversible, competitive inhibition of both human isozymes of 5aR with K(i) values of less than 10 nM. Furthermore, this compound binds to the androgen receptor with an IC50 equal to 8 nM. Compounds in this series are projected to be powerful antagonists of testosterone and dihydrotestosterone action in vivo, with potential utility in the treatment of prostatic carcinoma (PC). more...

Non-steroidal antiandrogens have been employed in the management of prostate cancer, but the mechanism of action is unclear due to a lack of good tissue culture models. The growth of a hamster ductus deferens cell line (DDT1) is highly dependent upon the addition of 10 nM testosterone to synthetic serum-free media. We describe a non-steroidal compound N-(4-chlorophenyl)-(Z,Z)-2,3-bis(-cyclopropylmethylene) cyclopentanecarboxamide (L-245976) which antagonizes the action of testosterone on DDT1 cells at 10 microM but exhibits little or no effect on cell growth by itself. This compound also blocks the binding of 3H-dihydrotestosterone (DHT) to the human androgen receptor (AR) with an IC50 of approximately 28 microM. In addition, L-245976 was found to antagonize DHT-dependent transactivation of the AR via the probasin gene promoter at comparable doses with no agonist activity. more...

The CphA metallo-beta-lactamase from Aeromonas hydrophilia has been expressed, purified and crystallized by the hanging-drop vapor-diffusion method using ammonium sulfate as the precipitant. The crystals exhibit orthorhombic symmetry (P2(1)2(1)2), with unit-cell parameters a = 40.75, b = 42.05, c = 128.88 A. There is one monomer in the asymmetric unit and the solvent content is estimated to be 44% by volume. A data set extending to 1.8 A has been measured. more...

Steroid 5alpha-reductase is required for the conversion of testosterone to dihydrotestosterone. Localization of type 1 5alpha-reductase in the sebaceous gland of skin offers the possibility for selective inhibition of this isozyme as a treatment for acne. The goals of these studies are to demonstrate the mechanism of inhibition of MK386 and its selectivity for type 1 5alpha-reductase. The apparent potency of MK386 differed depending on the source of the enzyme (i.e. recombinant vs. native), yet selectivity for type 1 5alpha-reductase was unchanged. Our results indicate that the apparent potency of MK386 is modulated by the membrane concentration of the assay. These results suggest that MK386 has a high affinity for the lipid-rich membrane environment of 5alpha-reductase. MK386 was also found to be a slow binding inhibitor of type 1 5alpha-reductase. However, the cause of this time-dependent inhibition is unrelated to partitioning of the inhibitor into the membrane because similar studies with type 2 5alpha-reductase indicate that MK386 is a reversible, competitive inhibitor. A number of counterscreens were developed to demonstrate that MK386 is a poor inhibitor of other steroid metabolizing enzymes. more...

The escalating number of multidrug resistant pathogens has demanded the swift development of new and potent antibiotics (ref. 2). Metallo-[beta]-lactamases (MBLs) continue to evolve, rendering the latest generation of carbapenem antibiotics useless (ref. 8). SPM-1, a recently discovered MBL, was isolated from a juvenile leukemia patient residing in a hospital in San Palo, Brazil just prior to the patient succumbing to septicemia brought on by Pseudomonas aeruginosa expressing SPM-1 (ref. 8). Screening of the Johns Hopkins Compound library of 1,514 FDA or FAD approved drugs (ref. 1) identified a novel SPM-1 inhibitor that is synergistically compatible with meropenem. Using clinically achievable concentrations, meropenem coupled with nadifloxacin inhibits Pseudomonas aeruginosa expressing SPM-1. This shotgun approach to new drug discovery provided a prompt solution to the grave problem of antibiotic resistant pathogens that are thriving in hospitals today. more...

Antibiotic-resistant bacteria continue to threaten human health through multiple mechanisms, including hydrolytic inactivation of beta-lactam antibiotics by metallo-beta-lactamases (MBLs). The SPM-1 enzyme, originally identified from a Pseudomonas aeruginosa clinical isolate, is a Class B beta-lactamase responsible for resistance in bacteria against antibiotics such as penicillins, cephalosporins, and carbapenems. Unlike Class A, C, and D beta-lactamases, which employ a serine residue in their active site, Class B enzymes possess one or two Zn atoms in the active site that play both a structural and catalytic role. A beta-lactamase inhibitor with co-administration of a beta-lactam antibiotic has proven to be an effective treatment against antibiotic-resistant bacteria whose resistance is due to serine-based beta-lactamases (e.g., amoxicillin/clavulanic acid). A similar clinical approach has not yet been developed for resistant bacteria possessing MBLs. The identification and development of specific and effective MBL inhibitors to combat this resistance could extend the utility of currently prescribed antibiotics such as cephalosporins and carbapenems. To discover MBL inhibitors, compound libraries are screened typically by enzymatic hydrolysis of a chromogenic substrate such as nitrocefin monitored by absorbance. Spectrophotometric assays, while valuable, lack the sensitivity and selectivity to screen natural product extract libraries because of the strongly absorbing nature of some extracts and the dilute concentrations of active components. An assay is described herein that monitors the SPM-1-catalyzed hydrolysis of penicillin G by high-performance (high-pressure) liquid chromatography-electrospray mass spectroscopy, which permits investigations with greater sensitivity and selectivity allowing the screening of natural product extracts for inhibitors of MBLs. more...

Yellow KK mice carrying the 'yellow obese' gene Ay are a well established polygenic model for human non-insulin dependent diabetes mellitus. These animals develop marked adiposity and decreased glucose tolerance relative to their control littermates, KK mice. The authors monitored glucose tolerance in KK-Ay mice over time and observed a significant (P more...

Carbapenem resistance continues to erode the effectiveness of antibiotics such as imipenem and meropenem in the clinic. Resistance mechanisms can include interplay between porin loss (membrane permeability), mutation of penicillin binding proteins necessary for cell division, and expression of class A, B and D beta-lactamases. Bacterial resistance to beta-lactams such as penicillin or amoxicillin has been overcome in the clinic using several strategies, including development of antibiotics not susceptible to hydrolysis by beta-lactamases, or co-administration of the antibiotic with beta-lactamase inhibitors. This overview will focus on progress since 2000 in identifying inhibitors of class B, or metallo-beta-lactamases with the aim of reversing carbapenem resistance. more...

IMP-1 metallo-beta-lactamase is a zinc metalloenzyme that confers antibiotic resistance to bacteria through the hydrolysis of beta-lactam antibiotics. Pathogens that express the enzyme show reduced susceptibility to carbapenems, such as meropenem and imipenem. In order to identify novel IMP-1 inhibitors, the National Cancer Institute (NCI) chemical diversity set was screened using 96-well high throughput screening format. The collection yielded several novel succinic acid derivatives that exhibited mixed inhibition of IMP-1 with compound 20707 having the highest affinity with a Ki value of 3.3 microM+/-1.7. The compounds are moderately potent inhibitors of IMP-1 with IC50 values ranging from 5.0 to 17 microM. An original chemical class of IMP-1 inhibitor, 2-((E)-(1,3-dihydroxy-2-methylpropan-2-ylimino)methyl)-4,6-diiodophenol, was discovered and was the most potent with an IC50 of 1.2 microM. NCI compounds, 20707, 140905 and 9746 sensitized a carbapenem-resistant laboratory strain of Escherichia coli to clinically achievable levels of meropenem. more...

Iseganan (IB-367) is a protegrin under development by IntraBiotics, as part of a larger protegrin program, for the potential treatment of oral mucositis, a frequent side effect of anticancer therapies. The company is developing three formulations of the drug: A rinse for the potential treatment of mucositis, an aerosolized liquid for the potential treatment of respiratory infection and a gel formulation for the potential treatment of pneumonia [376325]. Iseganan kills a broad-spectrum of bacteria and fungi, including those resistant to conventional antimicrobial drugs, by attaching to and destroying the integrity of the lipid cell membrane [241594]. Until August 1999, PharmaciaUpjohn was a codeveloper of iseganan. IntraBiotics re-acquired the global rights to iseganan in December 1999, and both companies agreed to terminate the collaboration [335766]. In May 2000, analysts at SG Cowen predicted the drug's potential market at US $100 to US $200 million [376325]. more...

IMP-1 metallo-beta-lactamase is a transferable carbapenem-hydrolyzing enzyme found in some clinical isolates of Pseudomonas aeruginosa, Serratia marcescens and Klebsiella pneumoniae. Bacteria that express IMP-1 show significantly reduced sensitivity to carbapenems and other beta-lactam antibiotics. A series of thioester derivatives has been shown to competitively inhibit purified IMP-1. As substrates for IMP-1, the thioesters yielded thiol hydrolysis products which themselves were reversible competitive inhibitors. The thioesters also increased sensitivity to the carbapenem L-742,728 in an IMP-1-producing laboratory stain of Escherichia coli, but will need further modification to improve their activity in less permeable organisms such as Pseudomonas and Serratia. Nonetheless, the thioester IMP-1 inhibitors offer an encouraging start to overcoming metallo-beta-lactamase-mediated resistance in bacteria. more...

Background: High level resistance to carbapenem antibiotics in gram negative bacteria such as Bacteroides fragilis is caused, in part, by expression of a wide-spectrum metallo-β-lactamase that hydrolyzes the drug to an inactive form. Co-administration of metallo-β-lactamase inhibitors to resistant bacteria is expected to restore the antibacterial activity of carbapenems. Results: Biphenyl tetrazoles (BPTs) are a structural class of potent competitive inhibitors of metallo-β-lactamase identified through screening and predicted using molecular modeling of the enzyme structure. The X-ray crystal structure of the enzyme bound to the BPT L-159,061 shows that the tetrazole moiety of the inhibitor interacts directly with one of the two zinc atoms in the active site, replacing a metal-bound water molecule. Inhibition of metallo-β-lactamase by BPTs in vitro correlates well with antibiotic sensitization of resistant B. fragilis . Conclusions: BPT inhibitors can sensitize a resistant B. fragilis clinical isolate expressing metallo-β-lactamase to the antibiotics imipenem or penicillin G but not to rifampicin. more...

A novel human coronavirus has been reported to be the causative agent of severe acute respiratory syndrome (SARS). Since replication of HcoVs depends on extensive proteolytic processing, the main proteinase, 3CLpro, is an attractive drug target for anti-SARS agents. We have employed molecular docking of a chemical database into the active site of 3CLpro to search for non-peptidyl inhibitors. One compound was identified to be the natural product sabadinine, isolated from a historical herbal remedy. more...

Publisher Summary Circulating C1g steroids, secreted from the testis, adrenal, and ovary serve as the source of hormonal androgens for endocrine function. Two androgens, testosterone (T) and 5a dihydrotestosterone (DHT) are responsible for the activation of the intracellular androgen receptor (AR) that, in turn, regulates gene transcription, and ultimately protein synthesis. Two major approaches have been employed to control androgen action: modulation of the AR-hormone interaction and inhibition of hormone production. The focus of this review are conditions that are amenable to hormonal manipulation and includes benign prostatic hyperplasia (BPH), prostatic carcinoma (PC), and skin-related problems, such as acne, seborrhea, androgenic alopecia, and hirsutism. Earlier reviews of these topics can be found in this series or elsewhere. The high incidence of BPH and PC in modern society has provided impetus for broadening the search for safe and specific agents to control agerelated phenomena of the androgen sensitive prostate gland. New agents, such as casodex and finasteride, appear to provide significant advances toward the treatment of PC and BPH, respectively, by offering ease of use and good side-effect profiles. The use of combined androgen ablation methods are likely to add to the length and quality of life for PC patients. Other approaches, such as the use of anti-sense DNA to block AR expression or blocking of the AR response elements on DNA, may lead to more specific effects, but their medical application appears to be more distant. more...

In the News Focus Story “A new day for Egyptian science?” (15 July, p. [278][1]), A. Lawler provides an accurate picture of a nation in dire need of revamping education as it struggles to define itself in the aftermath of the Mubarak dictatorship. Current Egyptian students can enroll only in government-controlled academic programs that serve more than 2.7 million students at public and private universities or public research institutes ([ 1 ][2]). Because of the complexity involved in centrally administering such a large system, quality has been sacrificed for quantity and innovation has been stifled. We believe that decentralization of higher education in Egypt could offer many benefits to students, faculty, and their surrounding communities. Faculty would be free to develop innovative curricula without the current constraints of a centralized approval process ([ 2 ][3]). Research centers could be managed independently, privatized, and/or linked to private-sector industries. The Egyptian Ministry of Higher Education has recently moved toward granting autonomy to university branches in Egypt's rural areas ([ 3 ][4]). This is a step in the right direction that should be expanded to give full independence to Egypt's universities. Pursuing a decentralization strategy would provide new opportunities for independent universities. They could adopt innovative management procedures and develop creative financial strategies that complement academic programs and research goals with academe and the private sector working closely together. Ultimately, such restructuring would boost Egypt's global competitiveness and serve as a model for the Middle East as the ripple of effects of the Arab Spring spread throughout the region. 1. [↵][5] 1. R. I. Selim, 2. M. El-Halawany Egyptian Ministry of Higher Education, “Guide to Higher Education in Egypt,” R. I. Selim, M. El-Halawany, Eds. (2007); [www.mohe-casm.edu.eg/Main\_menu/version/daleel\_talem_aaly/English.pdf][6]. 2. [↵][7] World Bank, “Higher Education Reform in the Middle East and North Africa” (World Bank, Report No. 62651, Washington, DC, 2011), vol. 1. 3. [↵][8] Egyptian Higher Education Report Team, “Higher education in Egypt: Country background report summary” (Egyptian Ministry of Higher Education, El Giza, Egypt, 2008). [1]: http://www.sciencemag.org/content/333/6040/278.summary [2]: #ref-1 [3]: #ref-2 [4]: #ref-3 [5]: #xref-ref-1-1 "View reference 1 in text" [6]: http://www.mohe-casm.edu.eg/Main_menu/version/daleel_talem_aaly/English.pdf [7]: #xref-ref-2-1 "View reference 2 in text" [8]: #xref-ref-3-1 "View reference 3 in text" more...

The News Story “Stepping away from the trees for a look at the forest” (17 December 2010, Science News staff, special section on Insights of the Decade, p. [1612][1]) describes the potential of network science to solve complex problems, including the use of crowd-sourcing. Network science has also been applied to disaster response, such as the aftermath of the magnitude 7.0 M W earthquake in Haiti in 2010. An open-source technology named Ushahidi (“testimony” in Swahili) ([ 1 ][2]) was used to create high-resolution maps of accessible roads through integration of more than 80,000 text messages and geographic information systems. This platform can also process voice messages, making it a useful tool for the illiterate. These aggregated data allowed more rapid transport of earthquake victims to hospitals, given the paucity of reliable road maps before the disaster. Similar open source tools such as Geo-Chat ([ 2 ][3], [ 3 ][4]) have been applied to disease outbreaks globally and to human rights issues in Burma ([ 4 ][5]), facilitating anonymous reporting of sexual violence, human trafficking, and child soldiers. Societal benefits of these technologies will broaden as more users revise methods for uploading, processing, visualizing, and interpreting data to inform public policy. 1. [↵][6] 1. C. C. Freifeld 2. et al ., PLoS Med. 7, e1000376 (2010). [OpenUrl][7][CrossRef][8][PubMed][9] 2. [↵][10] Innovative Support to Emergencies, Diseases, and Disasters (InSTEDD) ( ). 3. [↵][11] 1. D. Butler , Nat. News 10.1038/news.2009.187 (25 March 2009). doi:10.1038/news.2009.187 [OpenUrl][12][CrossRef][13] 4. [↵][14] Handheld Human Rights ([www.handheldhumanrights.org][15]/). [1]: /lookup/doi/10.1126/science.330.6011.1612 [2]: #ref-1 [3]: #ref-2 [4]: #ref-3 [5]: #ref-4 [6]: #xref-ref-1-1 "View reference 1 in text" [7]: {openurl}?query=rft.stitle%253DPLoS%2BMed%26rft.aulast%253DFreifeld%26rft.auinit1%253DC.%2BC.%26rft.volume%253D7%26rft.issue%253D12%26rft.spage%253De1000376%26rft.epage%253De1000376%26rft.atitle%253DParticipatory%2Bepidemiology%253A%2Buse%2Bof%2Bmobile%2Bphones%2Bfor%2Bcommunity-based%2Bhealth%2Breporting.%26rft_id%253Dinfo%253Adoi%252F10.1371%252Fjournal.pmed.1000376%26rft_id%253Dinfo%253Apmid%252F21151888%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [8]: /lookup/external-ref?access_num=10.1371/journal.pmed.1000376&link_type=DOI [9]: /lookup/external-ref?access_num=21151888&link_type=MED&atom=%2Fsci%2F331%2F6020%2F1010.2.atom [10]: #xref-ref-2-1 "View reference 2 in text" [11]: #xref-ref-3-1 "View reference 3 in text" [12]: {openurl}?query=rft.jtitle%253DNat.%2BNews%26rft_id%253Dinfo%253Adoi%252F10.1038%252Fnews.2009.187%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [13]: /lookup/external-ref?access_num=10.1038/news.2009.187&link_type=DOI [14]: #xref-ref-4-1 "View reference 4 in text" [15]: http://www.handheldhumanrights.org more...

The global pharmaceutical industry is facing diminishing returns from its massive investment in research and development. This is particularly troublesome because the industry has long enjoyed monopoly rents that come from innovative new drugs. The purpose of this paper is to examine the extant R&D practices in the industry and make a strong case for a shift to the open innovation model. Potential roadblocks to adopting the open innovation model are identified as well as ways to overcome these roadblocks. This conceptual paper makes use of archival R&D and sales data to support its contentions. more...

The launch of the AAAS Science and Human Rights Coalition, held in Washington, DC, on 14 to 16 January, offered an opportunity for AAAS-affiliated scientific organizations to participate in bridging communities of scientists and human rights organizations. A shared goal of this coalition is to articulate the right to “share in scientific advancement and its benefits” ([1][1]). I believe that this launch offers a rare opportunity in higher education to enhance partnerships between academicians in the sciences and the arts and humanities to engage student learning at all levels. Mary Robinson, a human rights advocate and former president of Ireland, pointed out an example: Physicians for Human Rights investigated an outbreak of cholera in Zimbabwe and found that it was due to the centralization of the water system by the Zimbabwean government and the subsequent degradation due to lack of proper maintenance ([2][2]). ![Figure][3] The AAAS Science and Human Rights Program.CREDIT: AAAS SCIENCE AND HUMAN RIGHTS PROGRAM, SHR.AAAS.ORG AAAS has established a “scientists on call” program ([3][4]) to contribute to humanitarian efforts such as this. Imagine the engagement of an undergraduate student in a science teaching laboratory analyzing data from sub-Saharan Africa that could provide critical insight for a human rights effort, ranging from analysis of contaminated water to biological samples from a suspected incident of genocide. With appropriate regulatory compliance and faculty supervision, a grassroots “students on call” effort could ensue. Techniques such as polymerase chain reaction or water analysis that are commonplace in the developed world may not be feasible or attainable in regions in crisis in the developing world. Incorporation of human rights into both science and general education curricula could have a profound effect on higher education and, importantly, on K-12 education by engagement of future teachers. 1. 1.[↵][5]United Nations Universal Declaration of Human Rights, Article 27. 2. 2.[↵][6]1. C. Beyrer, 2. F. Donaghue , The Washington Post A15 (8 January 2009). 3. 3.[↵][7]AAAS Science and Human Rights Program, “On-Call” Scientists ( ). [1]: #ref-1 [2]: #ref-2 [3]: pending:yes [4]: #ref-3 [5]: #xref-ref-1-1 "View reference 1. in text" [6]: #xref-ref-2-1 "View reference 2. in text" [7]: #xref-ref-3-1 "View reference 3. in text" more...

In the News Focus “Industrial-style screening meets academic biology” (8 August, p. [764][1]), J. Kaiser presents the discovery of several potential small-molecule therapeutics and probes for cellular function along with skeptical views from industrial scientists questioning “whether this massive effort is worth the time and money.” The goals of the pharmaceutical industry and academia are very different. Industry scientists are focused on discovering a highly specific and potent compound that can benefit human health. Academic scientists focus on finding compounds that can reveal novel cellular mechanisms, a basic tenet in chemical biology ([1][2]). It is this pursuit that allows the academician to foster student learning and interdisciplinary collaborations with faculty that could lead to a novel biological probe or a potential therapeutic. The current $100 million-per-year funding from the NIH Molecular Libraries Initiative (MLI) is a wise investment in the training of future scientists and teachers. Students working with faculty mentors on these screening efforts learn how to solve problems across all areas of science and mathematics; indeed, the “challenge of merging two cultures—biologists and chemists” is an opportunity for a better education ([2][3]). Such an interdisciplinary approach to science education is timely, given the recently passed Public Law 110-69, “America Competes Act,” which includes appropriation of $896 million for “education and human resources” ([3][4]) that will promote the training of future science and mathematics teachers. Regardless of the skepticism, I believe that the NIH MLI could “pay it forward” to our society in many ways. 1. 1.[↵][5] 1. S. L. Schreiber , Nat. Chem. Biol. 1, 64 (2005). [OpenUrl][6][CrossRef][7][PubMed][8][Web of Science][9] 2. 2.[↵][10] 1. R. L. Stein , J. Biomol. Screen. 8, 615 (2003). [OpenUrl][11][Abstract/FREE Full Text][12] 3. 3.[↵][13] Public Law 110-69 (H.R. 2272), sec. 7002, fiscal year 2008. [1]: /lookup/doi/10.1126/science.321.5890.764 [2]: #ref-1 [3]: #ref-2 [4]: #ref-3 [5]: #xref-ref-1-1 "View reference 1. in text" [6]: {openurl}?query=rft.stitle%253DNat%2BChem%2BBiol%26rft.aulast%253DSchreiber%26rft.auinit1%253DS.%2BL.%26rft.volume%253D1%26rft.issue%253D2%26rft.spage%253D64%26rft.epage%253D66%26rft.atitle%253DSmall%2Bmolecules%253A%2Bthe%2Bmissing%2Blink%2Bin%2Bthe%2Bcentral%2Bdogma.%26rft_id%253Dinfo%253Adoi%252F10.1038%252Fnchembio0705-64%26rft_id%253Dinfo%253Apmid%252F16407997%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [7]: /lookup/external-ref?access_num=10.1038/nchembio0705-64&link_type=DOI [8]: /lookup/external-ref?access_num=16407997&link_type=MED&atom=%2Fsci%2F322%2F5898%2F46.atom [9]: /lookup/external-ref?access_num=000232648200002&link_type=ISI [10]: #xref-ref-2-1 "View reference 2. in text" [11]: {openurl}?query=rft.jtitle%253DJournal%2Bof%2BBiomolecular%2BScreening%26rft.stitle%253DJ%2BBiomol%2BScreen%26rft.issn%253D1087-0571%26rft.aulast%253DStein%26rft.auinit1%253DR.%2BL.%26rft.volume%253D8%26rft.issue%253D6%26rft.spage%253D615%26rft.epage%253D619%26rft.atitle%253DHigh-Throughput%2BScreening%2Bin%2BAcademia%253A%2BThe%2BHarvard%2BExperience%26rft_id%253Dinfo%253Adoi%252F10.1177%252F1087057103260741%26rft_id%253Dinfo%253Apmid%252F14711386%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [12]: /lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NToic3BqYngiO3M6NToicmVzaWQiO3M6NzoiOC82LzYxNSI7czo0OiJhdG9tIjtzOjIxOiIvc2NpLzMyMi81ODk4LzQ2LmF0b20iO31zOjg6ImZyYWdtZW50IjtzOjA6IiI7fQ== [13]: #xref-ref-3-1 "View reference 3. in text" more...

A factor has been identified in extracts from human HeLa and hamster V79 cells that retards the electrophoretic mobility of several DNA restriction fragments modified with the antitumor drug cis-diamminedichloroplatinum(II) (cisplatin). Binding of the factor to cisplatin-modified DNA was sensitive to pretreatment with proteinase K, establishing that the factor is a protein. Gel mobility shifts were observed with probes containing as few as seven Pt atoms per kilobase of duplex DNA. By competition experiments the dissociation constant, Kd, of the protein from cisplatin-modified DNA was estimated to be (1-20) X 10(-10) M. Protein binding is selective for DNA modified with cisplatin, [Pt(en)Cl2] (en, ethylenediamine), and [Pt(dach)Cl2] (dach, 1,2-diaminocyclohexane) but not with chemotherapeutically inactive trans-diamminedichloroplatinum(II) or monofunctionally coordinating [Pt(dien)Cl]Cl (dien, diethylenetriamine) complexes. The protein also does not bind to DNA containing UV-induced photoproducts. The protein binds specifically to 1,2-intrastrand d(GpG) and d(ApG) cross-links formed by cisplatin, as determined by gel mobility shifts with synthetic 110-bp duplex oligonucleotides; these modified oligomers contained five equally spaced adducts of either cis-[Pt(NH3)2d(GpG) or cis-[Pt(NH3)2d(ApG)]. Oligonucleotides containing the specific adducts cis-[Pt(NH3)2d(GpTpG)], trans-[Pt(NH3)2d(GpTpG)], or cis-[Pt(NH3)2(N3-cytosine)d(G)] were not recognized by the protein. The apparent molecular weight of the protein is 91,000, as determined by sucrose gradient centrifugation of a preparation partially purified by ammonium sulfate fractionation. Binding of the protein to platinum-modified DNA does not require cofactors but is sensitive to treatment with 5 mM MnCl2, CdCl2, CoCl2, or ZnCl2 and with 1 mM HgCl2.(ABSTRACT TRUNCATED AT 250 WORDS) more...

Pyruvate kinase is an enzyme that catalyzes the formation of pyruvate from phosphenolpyruvate in glycolysis. There is a wealth of data on the activity of certain molecules and their effects on pyruvate kinase. This project aims to create an application that uses a pyruvate kinase dataset to determine the nature of unidentified molecules; whether or not they would be activators or inhibitors of this enzyme. This application uses an Apriori algorithm to identify or predict modulators of pyruvate kinase. This initial study focuses on simplified molecular input line entry specification (SMILES) text as target data to be mined. The three dimensional structure of pyruvate kinase is known and accessible though the Protein Data Bank (e.g., PDB code IA3W). more...

Purified human beta-hexosaminidase A (beta-N-acetylgulcosaminidase; 2-acetamido-2-deoxy-beta-D-glucoside acetamidodeoxyglucohydrolase, EC 3.2.1.30) has been labeled with 125I to high specific activity with the retention of 80% of its enzyme activity. The binding of this enzyme to sonicated synaptosomes from rat brain was shown to be a saturable and specific process. Glycoproteins containing a sialic acid-terminal oligosaccharide or a galactose-terminal oligosaccharide (i.e., alpha 1-acid glycoprotein and fetuin and their asialo derivatives) were strong inhibitors of the binding. In contrast, ovalbumin, which contains a mannose-rich oligosaccharide, and mannans were poor inhibitors of the binding. Of the monosaccharides tested, sialic acid, galactosamine, mannose, galactose, and lactose were inhibitory in decreasing potency of inhibition. Optimal binding occurred at pH 7.0 in the presence of 3 mM calcium ions. The binding was a linear function of synaptosomal protein concentration between 25 and 200 microgram of protein per assay and was directly proportional to time up to 3 hr, beyond which there was no further increase in specific binding. The data suggest a unique but complex mode of interaction of glycoproteins with receptors on synaptic membranes. more...

We have compared the sites of nucleotide incision on DNA damaged by oxidizing agents when cleavage is mediated by either Escherichia coli endonuclease III or an endonuclease present in bovine and human cells. E. coli endonuclease III, the bovine endonuclease isolated from calf thymus, and the human endonuclease partially purified from HeLa and CEM-C1 lymphoblastoid cells incised DNA damaged with osmium tetroxide, ionizing radiation, or high doses of UV light at sites of pyrimidines. For each damaging agent studied, regardless of whether the E. coli, bovine, or human endonuclease was used, the same sequence specificity of cleavage was observed. We detected this endonuclease activity in a variety of human fibroblasts derived from normal individuals as well as individuals with the DNA repair deficiency diseases ataxia telangiectasia and xeroderma pigmentosum. The highly conserved nature of such a DNA damage-specific endonuclease suggests that a common pathway exists in bacteria, humans, and other mammals for the reversal of certain types of oxidative DNA damage. more...

A simple, low‐cost, computerized, very low‐frequency lock‐in amplifier is described for signal‐to‐noise enhancement. This system is based on a low‐cost digital multimeter connected to a microcomputer through an IEEE‐488 interface. The system works with signals that can be modulated at ≃1 Hz. The signal‐to‐noise ratio, calculated in real time during data acquisition, can be used to terminate acquisition either after the desired signal‐to‐noise ratio is reached or after a specified number of samples has been averaged. The system is also suitable for eliminating large constant backgrounds on small signals. Possible applications include spectrophotometry, spectrofluorimetry, and ac calorimetry. more...