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The second biannual Alpine Winter Conference on Medicinal and Synthetic Chemistry (short: Alpine Winter Conference) took place January 19-23, 2020, in St. Anton in western Austria. There were roughly 180 attendees from around the globe, making this mid-sized conference particularly conducive to networking and exchanging ideas over the course of four and a half days. This report summarizes the key events and presentations given by researchers working in both industry and academia.

The second biannual Alpine Winter Conference on Medicinal and Synthetic Chemistry (short: Alpine Winter Conference) took place January 19-23, 2020, in St. Anton in western Austria. There were roughly 180 attendees from around the globe, making this mid-sized conference particularly conducive to networking and exchanging ideas over the course of four and a half days. This report summarizes the key events and presentations given by researchers working in both industry and academia.

The Medicinal and Bioorganic Chemistry Foundation (MBCF) hosted its 13th biannual Winter Conference on Medicinal and Bioorganic Chemistry (WCMBC) this past January 22nd -26th in Steamboat Springs, Colorado (USA). The gathering this year kept true to the tradition of this conference series, with an impressive lineup of presenters from both academia and industry. With about 125 delegates, the conference took all the advantages of a mid-sized gathering: a sufficiently wide spectrum of scientists in attendance, yet an intimate atmosphere conducive to solid networking and frank, open discussions. This conference report summarizes the presentations that were given this year.

Moving in medchem: Editors David Peralta and Scott Williams look back at the ChemMedChem 10th anniversary celebration in 2016 and introduce exciting developments for the journal in 2017, including the expansion of its scope to nanomedicine, the introduction of Patent Reviews, the addition of new board members, and the publication of special issues related to the expanded scope.

Happy birthday! Issue 01/2016 marks the 10th anniversary of ChemMedChem. With a complete set of 10 volumes, the Editorial Team takes a look back at how the journal, and indeed the field of medicinal chemistry, have evolved and changed over the past decade.

A simple procedure for the preparation of octadecylsiloxane self-assembled monolayers (SAMs) on float glass substrates is described. The method utilizes commercial octadecyltriethoxysilane, OTE: n-C18H37Si(OCH2CH3)3, as the SAM precursor, with deposition accomplished in toluene solution using n-butylamine as catalyst. This synthetic approach obviates the use of the problematic trichlorosilanes typically required for the preparation of high quality SAMs, and is characterized by a wide ‘process window,’ utilizing off-the-shelf reagents without special handling.

A pretest/posttest design was used to investigate the experiences of participants on a university-sponsored ski/snowboard trip to Interlaken, Switzerland. Self-administered questionnaires measuring benefits sought, destination image, satisfaction, and risk perception were distributed during transit. Of the 90 participants, 55 (61%) completed the pretest questionnaire. Thirty-nine (43.3%) completed and returned the posttest questionnaires via e-mail. Additional data were provided by participant observation and open-ended responses within the questionnaire. Frequencies and t-tests revealed that students sought benefits related to novelty, excitement, and social opportunities. Images were of scenic beauty, unique skiing, and cultural attractions. Participants were unconcerned with risks involved in travel after September 11, 2001. Gender, involvement, and previous travel experience were also examined. Recommendations for planners of similar trips are to consider the interests of nonskiers and skiers in marketing, capitalizing on popular images of destinations.

We have examined the effects of truncated Bid (tBid) and ceramide on mitochondrial membrane integrity and cytochrome c release, using mitochondria with intact outer membranes. While tBid permeabilizes the outer membrane and efficiently stimulates cytochrome c release, digitonin is unable to cause cytochrome c release in the absence of salt. Ceramides did not permeabilize the mitochondrial outer membrane, and stimulated cytochrome c release only in the presence of digitonin. Taken together, these observations support a model for cytochrome c release in which the first step is dissociation from the inner membrane followed by transit across the outer membrane.

The role of nuclear membrane phospholipids as targets of phospholipases resulting in the generation of nu- clear signaling messengers has received attention. In the present study, we have exploited the utility of electrospray ionization mass spectrometry to determine the phospho- lipid content of nuclei isolated from perfused hearts. Rat heart nuclei contained choline glycerophospholipids com- posed of palmitoyl and stearoyl residues at the sn -1 position with oleoyl, linoleoyl, and arachidonoyl residues at the sn -2 position. Diacyl molecular species were the predominant molecular subclass in the choline glycerophospholipids, with the balance of the molecular species being plasmalo- gens. In the ethanolamine glycerophospholipid pool from rat heart nuclei approximately 50% of the molecular spe- cies were plasmalogens, which were enriched with arachi- donic acid at the sn -2 position. A 50% loss of myocytic nu- clear choline and ethanolamine glycerophospholipids was observed in hearts rendered globally ischemic for 15 min followed by 90 min of reperfusion in comparisons with the content of these phospholipids in control perfused hearts. The loss of nuclear choline and ethanolamine glycerophos- pholipids during reperfusion of ischemic myocardium was partially reversed by the calcium-independent phospholi- pase A 2 (iPLA 2 ) inhibitor bromoenol lactone (BEL), sug- gesting that the loss of nuclear phospholipids during ischemia/reperfusion is mediated, in part, by iPLA 2 . West- ern blot analyses of isolated nuclei from ischemic hearts demonstrated that iPLA 2 is translocated to the nucleus after myocardial ischemia. Taken together, these studies have demonstrated that nuclear phospholipid mass decreases after myocardial ischemia by a mechanism that involves, at least in part, phospholipolysis mediated by iPLA 2 . — Williams, S. D., F-F. Hsu, and D. A. Ford. Electrospray ion- ization mass spectrometry analyses of nuclear membrane phospholipid loss after reperfusion of ischemic myocar- dium. J. Lipid Res. 2000. 41: 1585-1595.

The E. coli adenine glycosylase MutY is a member of the base excision repair (BER) superfamily of DNA repair enzymes. MutY plays an important role in preventing mutations caused by 7, 8-dihydro-8-oxo-2'-deoxyguanosine (OG) by removing adenine from OG:A base pairs. Some enzymes of the BER superfamily catalyze a strand scission even concomitant with base removal. These bifunctional glycosylase/AP lyases bear a conserved lysine group in the active site region, which is believed to be the species performing the initial nucleophilic attack at C1' in the catalysis of base removal. Monofunctional glycosylases such as MutY are thought to perform this C1' nucleophilic displacement by a base-activated water molecule, and, indeed, the conservation of amine functionality positioning has not been observed in protein sequence alignments. Bifunctional glycosylase/AP lyase activity was successfully engineered into MutY by replacing serine 120 with lysine. MutY S120K is capable of catalyzing DNA strand scission at a rate equivalent to that of adenine excision for both G:A and OG:A mispair substrates. The extent of DNA backbone cleavage is independent of treating reaction aliquots with 0.1 M NaOH. Importantly, the replacement of the serine with lysine results in a catalytic rate that is compromised by at least 20-fold. The reduced efficiency in the glycosylase activity is also reflected in a reduced ability of S120K MutY to prevent DNA mutations in vivo. These results illustrate that the mechanisms of action of the two classes of these enzymes are quite similar, such that a single amino acid change is sufficient, in the case of MutY, to convert a monofunctional glycosylase to a bifunctional glycosylase/AP lyase.

The mutY gene product of Escherichia coli is a 39-kDa protein that catalyzes the removal of adenine bases mispaired with 2'-deoxyguanosine and 7,8-dihydro-8-oxo-2'-deoxyguanosine (OG) in DNA. Although adenine removal proceeds via monofunctional glycosylase activity, MutY is able to form covalent adducts with substrate DNA in the presence of borohydride, a trait otherwise known to be associated only with enzymes having bifunctional glycosylase/AP lyase activity. To help identify active site residues involved in the formation of MutY-DNA adducts in the presence of borohydride, a series of site-directed mutant forms of MutY were generated. Our data show that Lys 142 is the primary residue involved in cross-link formation. The absence of Lys 142 results in near elimination of the enzyme-DNA adducts formed relative to wild-type, suggesting that this residue is the primary one involved in forming covalent associations with DNA during MutY catalysis. Importantly, the enzymatic activity and DNA binding of the K142A enzyme is nearly identical to the WT enzyme. This shows that formation of the covalent intermediate is not required for adenine removal by MutY. Furthermore, this suggests that the covalent intermediate is formed by reaction of Lys 142 with the OG/G:(AP site) product, and this may be a consequence of MutY's unusually high affinity for the product of its glycosylase action.

The Escherichia coli adenine glycosylase MutY is involved in the repair of 7,8-dihydro-8-oxo-2'-deoxyguanosine (OG):A and G:A mispairs in DNA. DNA strand cleavage via beta-elimination (beta-lyase) activity coupled with MutY's removal of misincorporated adenine bases was sought using both qualitative and quantitative methods. The qualitative assays demonstrate formation of a Schiff base intermediate which is characteristic of DNA glycosylases catalyzing a concomitant beta-lyase reaction. Borohydride reduction of the Schiff base results in the formation of a covalent DNA-MutY adduct which is easily detected in SDS-PAGE experiments. However, quantitative activity assays which monitor DNA strand scission accompanying base release suggest MutY behaves as a simple monofunctional glycosylase. Treatment with base effects DNA strand cleavage at apurinic/apyrimidinic (AP) sites arising via simple glycosylase activity. The amount of cleaved DNA in MutY reactions treated with base is much greater than that in non-base treated reactions, indicating that AP site generation by MutY is not associated with a concomitant beta-lyase step. As standards, identical assays were performed with a known monofunctional enzyme (uracil DNA glycosylase) and a known bifunctional glycosylase/lyase (FPG), the results of which were used in comparison with those of the MutY experiments. The apparent inconsistency between the data obtained for MutY by the qualitative and quantitative methods underscores the current debate surrounding the catalytic activity of this enzyme, and a detailed explanation of this controversy is proposed. The work presented here lays ground for the identification of specific active site residues responsible for the chemical mechanism of MutY enzyme catalysis.

The DNA repair enzyme MutY plays an important role in the prevention of DNA mutations caused by the oxidatively damaged lesion 7,8-dihydro-8-oxo-2‘-deoxyguanosine (OG) by removal of misincorporated adenine residues in OG:A mismatched base pairs using N-glycosylase activity. MutY also has glycosylase activity toward adenine in the mismatched base-pairs G:A and C:A. We have investigated the interaction of MutY with DNA duplexes containing the 2‘-deoxyadenosine (A) analogs 2‘-deoxytubercidin (7-deaza-2‘-deoxyadenosine, Z) and 2‘-deoxyformycin A (F). Both F and Z should effectively mimic the recognition properties of A but be resistant to the glycosylase activity of MutY, owing to their structural properties. Thus, these derivatives will provide a method for forming a stable MutY−substrate analog complex amenable to structural and biochemical investigation. We find that oligonucleotide duplexes containing OG/G:F and OG/G:Z base-pairs are not substrates for MutY as expected. Using a gel retardation method to m...

The array of categorical public programs for multineed families has often resulted in fragmented, ineffective, and inefficient services that add to the complexity and frustration experienced by these families. Utah's initiative to develop family-centered, community-based, coordinated services has encountered five major management challenges including (a) resisting nonproductive agency reorganization, (b) maintaining a focus on systems change rather than the creation of yet another new program, (c) changing the culture of service providers, (d) balancing the priorities of prevention, core treatment, and crisis services, and (e) maintaining an emphasis on a family-centered system. Weathering the political preferences for service specialization, a “quick-fix” to social problems, the aloof posture of the judicial system, and oversimplified approaches to evaluation present additional challenges. Sustaining true system change will require accountability, broad community involvement, and skilled leadership.

Lack of access to health care by those medically underserved results from a complex of social and economic factors. Solutions to the problem will require, at a minimum, removal of financial barriers and assurance of availability of qualified providers. The authors examine public policies designed to impact the supply and training of health care providers in terms of their short- and long-term effectiveness in influencing the composition of the health care workforce. They analyze data from a series of qualitative studies with family practice residents, providers, and key personnel from family practice residency programs for insights to help identify candidates who could be successful in needy environments, and in understanding providers’ perceptions of benefits and drawbacks of working with the underserved. The authors recommend a strategy for recruiting candidates better matched to the requirements of practice with the underserved, revising curricula to provide needed training to facilitate providers’ success in underserved settings, and designing practice environments supportive of providers working with underserved populations.

Objective To investigate the personal characteristics and professional experiences of medical providers working with medically underserved urban populations. Design Focus groups of primary care providers. Setting Public and private clinics in Salt Lake City, Utah, in which the providers had ongoing relationships with medically underserved patients. Participants Twenty-four providers (11 men and 13 women), including 12 physicians (three family physicians, seven pediatricians, and two psychiatrists), one dentist, three physician assistants, and eight nurse practitioners participated in three focus groups. Main outcome measure Interpretative analysis of verbatim quotations regarding personal beliefs, feelings, and practice experiences. Results Participants revealed a strong sense of service to humanity and pride in making a difference. They thrive on the challenge of creatively dealing with their patients' complex human needs with limited health care resources. Factors critical to survival in an urban underserved setting include a hardy personality style, flexible but controllable work schedule, and multidisciplinary practice team. The camaraderie and synergy of teams generate personal support and opportunities for continuing professional development. Conclusions Increasing the numbers of health care professionals wanting to work with the medically underserved may be facilitated through refining admissions criteria to schools for health care professionals to include values and personality characteristics, emphasizing within curricula the important skills and practice styles necessary to work with underserved patients, and ensuring that underserved practice environments provide support through multidisciplinary teams and structured work hours. These potentially effective approaches could increase success in recruiting and retaining health care professionals to work with medically underserved patients.

The shortage of providers in rural areas is threatening the quality and availability of health care in many communities. The causes of the provider shortage are many and varied-from economic to social to personal. Government programs have addressed the issue of provider supply by offering scholarships and loan repayment programs for medical students who then must fulfil service obligations in underserved settings, among which are rural areas. Experience has shown that once providers complete their obligations under these grant programs, retention of providers in rural areas becomes an even more critical issue. Using focus group research, this study explores the practice setting choices of a group of physicians currently practicing in rural areas. The discussion reveals that personal values are one of the primary motivators for choosing to practice in rural settings while lack of availability of career opportunities for spouses and educational opportunities for children are major obstacles. The health care system poses barriers to success for providers in rural settings. The key rewards from rural practice are the ability to become integrated into the local community and the provider/patient relationships that develop in such settings. These findings are used as the basis for proposing recruitment and retention strategies for providers to improve access to medical care by patients in rural areas.

Study objective. To evaluate the effects of setting, type of supervision, and time in clinic on the resident continuity clinic experience. Design. Prospective cohort with preintervention and postintervention measures. Settings. Pediatric residents selected one of three clinic settings for their continuity clinic experience. These included a traditional, university-based clinic, private practice offices, and publicly funded community-based clinics. Subjects. All pediatric residents at the University of Utah Health Sciences Center, July 1985 through June 1991. Interventions. Using varied clinic sites, matching residents one or two to one with preceptors for their continuity clinic, increasing continuity clinic from 1 to 2 half-days per week. Measurements and main results. Residents in private offices had the most varied experience, seeing more patients, more acute care, and a broader age range of patients than residents at other sites. They were more likely both to be observed by their preceptors during patient visits and to observe their preceptors delivering care. Because the number of patients seen per session rose, increasing continuity clinic time from one to two half-days per week more than doubled the number of patients seen per week. Increased time away from hospital did not affect scores on the Pediatric In-Training Examination. While test scores were similar for incoming residents, those in private offices scored higher on the final Behavioral Pediatrics Examination (P < .05). Conclusions. Clinic setting, time in clinic, and faculty supervision affect the quality of the continuity clinic experience. Increased time in clinic resulted in a broader exposure to patients. Residents placed in private offices had a more varied patient mix, were more closely supervised, and seemed to gain primary care skills more rapidly than residents at other sites.

Because postneonatal circumcision includes the risk of general anesthesia and costs more than elective neonatal circumcision, a retrospective study was performed to describe the population currently undergoing postneonatal circumcision and to identify the factors influencing decisions that lead to this procedure. A chart review and follow-up telephone survey were done to gather information concerning patients admitted for postneonatal circumcision to two Salt Lake City hospitals during a 2-year period. From the 135 patients eligible for analysis, two distinct groups emerged: the "sick" group (n = 52)—those who had neonatal complications, and the "well" group (n = 83)—those with no neonatal complications. The median age at circumcision was 5.5 months for the boys in the sick group and 35 months for the boys in the well group (P < .001, Student's t test). During the neonatal period, 32% of families in the well group received anticircumcision advice from their primary care physician. The decision in favor of circumcision was made by two thirds of the families of sick infants before their sons were 6 weeks of age. Other surgery was performed concurrent with the circumcision in 44% of patients in the sick group and 24% of patients in the well group (P < .0001, χ2). Balanitis, phimosis, or a physician's recommendation were listed as the primary reason for postneonatal circumcision by 50% of patents in the well group. Phimosis was listed by the surgeon as an indication for postneonatal circumcision in 65% of all patients's charts, although only 13% of parents listed phimosis as an indication for their children's circumcision. According to this profile of two distinct populations of postneonatal circumcision patients, pediatricians may be able to reduce the incidence of this procedure by providing support of individual preferences and objective information regarding circumcision to families of healthy infants during the neonatal period; by anticipating and facilitating the decisions surrounding neonatal circumcision for families of sick infants; and by educating families of uncircumcised boys about foreskin care and development during regular well-child visits.

The tricarboxylate reagent benzene-1,3,5-triacetic acid (BTA) was used to attach 5'-aminated DNA primers and templates on an aminosilanized glass surface for subsequent generation of DNA colonies by in situ solid-phase amplification. We have characterized the derivatized surfaces for the chemical attachment of oligonucleotides and evaluate the properties relevant for the amplification process: surface density, thermal stability towards thermocycling, functionalization reproducibility and storage stability. The derivatization process, first developed for glass slides, was then adapted to microfabricated glass channels containing integrated fluidic connections. This implementation resulted in an important reduction of reaction times, consumption of reagents and process automation. Innovative analytical methods for the characterization of attached DNA were developed for assessing the surface immobilized DNA content after amplification. The results obtained showed that the BTA chemistry is compatible and suitable for forming highly dense arrays of DNA colonies with optimal surface coverage of about 10 million colonies/cm2 from the amplification of initial single-template DNA molecules immobilized. We also demonstrate that the dsDNA colonies generated can be quantitatively processed in situ by restriction enzymes digestion. DNA colonies generated using the BTA reagent can be used for further sequence analysis in an unprecedented parallel fashion for low-cost genomic studies. © 2006 Oxford University Press.

The efforts of families, health care providers, and public health programs to optimize health care and health outcomes for children are often limited by the lack of timely, complete, and accurate health information. Families frequently serve as the messenger between providers in providing clinical details that they may not understand, because the paper record of previous care is unavailable. Providers believe in the value of good information, but haven't the time, training, or financial resources to create better data sharing methods. Public health programs often must rely on unacceptably slow, redundant, or otherwise limited data collection efforts to provide population-based assessments of child health problems that inform public policy and program development. Integrated child health information systems allow the appropriate, secure sharing of health data that are critical to improving these processes. Developing such systems will require a strong commitment from these 3 stakeholder groups and attention to human values as well as technical challenges.

Background — Linkage of the 11–amino-acid transduction domain of HIV TAT to a heterologous protein allows the protein to be transduced readily into cells. Methods and Results — In this study, we inserted the apoptosis repressor with caspase recruitment domain (ARC) or β-galactosidase (β-gal) cDNA into the pTAT-hemagglutinin bacterial expression vector to produce genetic in-frame TAT-ARC or TAT-β-gal fusion proteins for use in cell culture and in Langendorff perfusion of adult rat hearts. TAT-β-gal and TAT-ARC were conjugated with Texas Red and could be detected in >95% of cells. TAT-ARC was able to protect H9c2 cells against cell death mediated by hydrogen peroxide, as measured by protection against the loss of mitochondrial membrane potential and preservation of nuclear morphology. Isolated adult hearts were perfused with recombinant TAT-β-gal or TAT-ARC (20 nmol/L) for 15 minutes and then subjected to 30 minutes of global no-flow ischemia, followed by 2 hours of reperfusion. Protein transduction was assessed by Western blotting of cell lysates and cytosolic and mitochondrial fractions and by fluorescence microscopy of Texas Red–conjugated TAT proteins. TAT-β-gal and TAT-ARC readily transduced into perfused hearts and were homogeneously distributed. Infarct size was determined by 2,3,5-triphenyltetrazolium chloride staining, and creatine kinase release was measured. Transduction of TAT-ARC was cardioprotective when administered before global ischemia and reperfusion. Conclusions — Our results demonstrate that TAT-linked fusion protein transduction into the myocardium is feasible and that transduction of TAT-ARC is protective in cell culture and in the perfused heart.

MutY is an Escherichia coli DNA repair enzyme that binds to 8-oxo-G:A and G:A mismatches and catalyzes the deglycosylation of the mismatched 2‘-deoxyadenosine. We have applied DNA-mediated charge transport to probe the interaction of MutY with its DNA substrate. Oligonucleotides synthesized with a tethered rhodium intercalator and guanine doublets placed before and after the MutY binding site are used to assay for base flipping activity by MutY. On the basis of this assay, we find no evidence that MutY uses progressive base flipping as a means to find its binding site; protein binding does not perturb long-range DNA charge transport. DNA-mediated charge transport can be utilized to promote protein−DNA cross-linking from a distance. Long-range oxidation of 8-oxo-G within the MutY binding site using tethered rhodium intercalators promoted cross-linking and yielded information on MutY side chains that interact with this base. On the basis of photooxidative cross-linking of the wild type but not K142A mutant, it is evident that, within the protein complex, lysine 142 makes important contacts with 8-oxo-G.

Calcium-independent phospholipase A(2) (iPLA(2)) is the predominant phospholipase A(2) present in myocardium, and its pathophysiological role in acute myocardial infarction has been suggested by the rapid increase in membrane-associated iPLA(2) activity during myocardial ischaemia and reperfusion (I/R). We therefore examined iPLA(2) in mitochondrial fractions prepared from Langendorff-perfused adult rabbit hearts. Our studies indicate that iPLA(2)beta is present in rabbit heart mitochondrial inner membranes with no apparent translocation during ischaemia, I/R or preconditioning. Mitochondrion-associated iPLA(2) was catalytically competent and exhibited 2-, 3- and 2.5-fold increases in measured iPLA(2) activity following ischaemia, I/R and preconditioning, respectively, when compared with the activity of iPLA(2) measured in mitochondria from control hearts. Mitochondrial phospholipids are essential for maintaining the ordered structure and function of the organelle. I/R resulted in a rapid overall decrease in phosphatidylcholine and phosphatidylethanolamine glycerophospholipid species, as determined by electrospray ionization MS, that was partially alleviated by pretreatment of hearts with the iPLA(2)-specific inhibitor, bromoenol lactone (BEL). Pretreatment of I/R hearts with 10 microM BEL significantly reduced the infarct size almost to that of continuously perfused hearts and was cardioprotective only when administered prior to ischaemia. Cardioprotection by BEL was reversed by the simultaneous perfusion of 100 microM 5-hydroxydecanoate, implicating the mitochondrial K(ATP) channel in BEL-mediated protection from I/R. Preconditioning also significantly reduced the infarct size in response to I/R but protection was lost by concurrent perfusion of 10 microM arachidonic acid. Taken together, these data strongly implicate mitochondria-associated iPLA(2) in the signal transduction of myocardial I/R injury.

In isolated, perfused adult rat hearts, global ischemia increased the phosphorylation of cAMP response element-binding protein (CREB) relative to control levels, and this phosphorylation was reversed with reperfusion. CREB phosphorylation elicited by 5 min of global ischemia was sensitive to treatments with the calcium-independent phospholipase A2(iPLA2) inhibitor bromoenol lactone (BEL) and occurred in the absence of increases in myocardial cAMP content. In contrast, CREB phosphorylation elicited by 15 min of global ischemia was likely mediated by elevated cAMP levels. The expression of c- fos, in response to brief myocardial ischemia, was also sensitive to BEL treatment. The induction of iPLA2-mediated CREB phosphorylation was further substantiated by the observations that lysoplasmenylcholine increased both the phosphorylation of CREB and the induction of c- fosexpression in the absence and presence of BEL. CREB phosphorylation in both ischemic hearts and lysoplasmenylcholine-perfused hearts was inhibited by pretreatment of hearts with the specific cAMP-dependent protein kinase (PKA) inhibitor H-89. Taken together, these data demonstrate that iPLA2mediates CREB phosphorylation through a PKA-dependent pathway during brief periods of myocardial ischemia, possibly through the formation of lysophospholipids.

Escherichia coli MutY is an adenine glycosylase involved in base excision repair that recognizes OG:A (where OG = 7, 8-dihydro-8-oxo-2'-deoxyguanosine) and G:A mismatches in DNA. MutY contains a solvent-exposed polypeptide loop between two of the cysteine ligands to the [4Fe-4S](2+) cluster, referred to as the iron-sulfur cluster loop (FCL) motif. The FCL is located adjacent to the proposed active site pocket and has been suggested to be part of the DNA binding surface of MutY (Y. Guan et al., 1998, Nat. Struct. Biol. 5, 1058-1064). In order to investigate the role of specific residues within the FCL motif, we have determined the effects of replacing arginine 194, lysine 196, and lysine 198 with alanine on the enzymatic properties of MutY. The properties of the R194A, K196A, and K198A enzymes were also compared to the properties of mutated enzymes in which lysine residues near the active site pocket were replaced with alanine or glycine. Substrate recognition was evaluated using a duplex containing a 2'-deoxyadenosine analog in a base pair opposite G or OG. These results indicate that removal of positively charged amino acids within the FCL and the active site compromise the ability of the enzyme to bind to the substrate analog. However, only the K198A enzyme exhibited a significant reduction (15-fold) of the rate of adenine removal from a G:A base pair-containing duplex. This is the first direct evidence that Lys 198 within the FCL motif of MutY has a role in specific damage recognition and removal. Furthermore, these results suggest that the FCL motif is intimately involved in the base removal process.

Plasmalogen-specific, calcium-independent phospholipase A2 (iPLA2) is activated during myocardial ischemia. Accordingly, we have assessed the activation of myocardial protein kinases by the iPLA2 product, lysoplasmenylcholine. Lysoplasmenylcholine-activated protein kinase activity from heart cytosol fractionated on a DE-52 column was identified as cAMP-dependent protein kinase (PKA) based on the following: (1) protein kinase activity stimulated by cAMP and lysoplasmenylcholine co-eluted on sequential chromatographic steps; (2) lysoplasmenylcholine-activated protein kinase activity was inhibited by the PKA inhibitor, PKI; and (3) the unprimed PKA form generated from the primed form of PKA was activated by cAMP and lysoplasmenylcholine. These results demonstrate a novel mechanism for PKA activation by lysoplasmenylcholine.

The injury-related mortality rate for Native American children between the ages of 1 and 4 years is nearly three times that of the same age group in the general population. To assess injury prevention awareness in urban Native American families, we administered 39 age-appropriate questions from the Framingham Safety Survey to 50 Native American families and 100 other families and developed an answer scoring system to analyze and compare survey responses. Survey responses revealed that Native American families are less likely to keep small objects, household products, and medicines out of the reach of their children and to possess and understand the use of ipecac. Although urban Native-American families appear to be less aware of ingestion prevention practices than other urban families, these and other deficiencies in injury prevention awareness are more likely the result of factors related to their low-income status than to culturally based practices.

We present the results from a photometric monitoring program of 15 open cluster stars and one weak-lined T Tauri star during late 1993/early 1994. Several show rotators which are members of the Alpha Persei, Pleiades, and Hyades open clusters have been monitored and period estimates derived. Using all available Pleiades stars with photometric periods together with current X-ray flux measurements, we illustrate the X-ray activity/rotation relation among Pleiades late-G/K dwarfs. The data show a clear break in the rotation-activity relation around P approximately 6-7 days -- in general accordance with previous results using more heterogeneous samples of G/K stars.

We have obtained spectral types, H alpha equivalent widths, and optical photometry for a small sample of late K and M dwarf candidate members of the Praesepe open cluster. At least for the small sample of stars we have observed, all of the Paesepe members later than M2 have H alpha in emission. The chromospheric activity of the Praesepe satrs is essentially the same as that for Hyades members of the same mass, as expected since the two clusters are thought to be the same age.