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The Internet has become an increasingly important part of teen culture; however, there still remains little in the medical/psychiatric literature pertaining to the impact of the Internet on adolescent development. Despite the potential problems associated with communication online, the Internet offers a variety of positive opportunities for teens. In this report, we present a case study that illustrates the Internet as a helpful tool in a 15-year-old adolescent boy with a history of chronic neurological illness accompanied by refractory psychosis. Although the case emphasizes some of the ways in which the Internet may have a positive impact on adolescent development, further research is indicated to evaluate the contexts in which the Internet serves healthy developmental processes and those in which its influence is potentially deleterious.

Proline utilization A (PutA) from Escherichia coli is a multifunctional flavoprotein that is both a transcriptional repressor of the proline utilization (put) genes and a membrane-associated enzyme which catalyzes the 4-electron oxidation of proline to glutamate. Previously, proline was shown to induce PutA-membrane binding and alter the intracellular location and function of PutA. To distinguish the roles of substrate binding and FAD reduction in the mechanism of how PutA changes from a DNA-binding protein to a membrane-bound enzyme, the kinetic parameters of PutA-membrane binding were measured under different conditions using model lipid bilayers and surface plasmon resonance (SPR). The effects of proline, FAD reduction, and proline analogues on PutA-membrane associations were determined. Oxidized PutA shows no binding to E. coli polar lipid vesicles. In contrast, proline and sodium dithionite induce tight binding of PutA to the lipid bilayer with indistinguishable kinetic parameters and an estimated dissociation constant (K(D)) of <0.01 nM (pH 7.4) for the reduced PutA-lipid complex. Proline analogues such as L-THFA and DL-P5C also stimulate PutA binding to E. coli polar lipid vesicles with K(D) values ranging from approximately 3.6 to 34 nM (pH 7.4) for the PutA-lipid complex. The greater PutA-membrane binding affinity (>300-fold) generated by FAD reduction relative to the nonreducing ligands demonstrates that FAD reduction controls PutA-membrane associations. On the basis of SPR kinetic analysis with differently charged lipid bilayers, the driving force for PutA-membrane binding is primarily hydrophobic. In the SPR experiments membrane-bound PutA did not bind put control DNA, confirming that the membrane-binding and DNA-binding activities of PutA are mutually exclusive. A model for the regulation of PutA is described in which the overall translocation of PutA from the cytoplasm to the membrane is driven by FAD reduction and the subsequent energy difference ( approximately 24 kJ/mol) between PutA-membrane and PutA-DNA binding.

Proline dehydrogenase (PRODH) catalyzes the first step of proline catabolism, the flavin-dependent oxidation of proline to Delta(1)-pyrroline-5-carboxylate. Here we present a structure-based study of the PRODH active site of the multifunctional Escherichia coli proline utilization A (PutA) protein using X-ray crystallography, enzyme kinetic measurements, and site-directed mutagenesis. Structures of the PutA PRODH domain complexed with competitive inhibitors acetate (K(i) = 30 mM), L-lactate (K(i) = 1 mM), and L-tetrahydro-2-furoic acid (L-THFA, K(i) = 0.2 mM) have been determined to high-resolution limits of 2.1-2.0 A. The discovery of acetate as a competitive inhibitor suggests that the carboxyl is the minimum functional group recognized by the active site, and the structures show how the enzyme exploits hydrogen-bonding and nonpolar interactions to optimize affinity for the substrate. The PRODH/L-THFA complex is the first structure of PRODH with a five-membered ring proline analogue bound in the active site and thus provides new insights into substrate recognition and the catalytic mechanism. The ring of L-THFA is nearly parallel to the middle ring of the FAD isoalloxazine, with the inhibitor C5 atom 3.3 A from the FAD N5. This geometry suggests direct hydride transfer as a plausible mechanism. Mutation of conserved active site residue Leu432 to Pro caused a 5-fold decrease in k(cat) and a severe loss in thermostability. These changes are consistent with the location of Leu432 in the hydrophobic core near residues that directly contact FAD. Our results suggest that the molecular basis for increased plasma proline levels in schizophrenic subjects carrying the missense mutation L441P is due to decreased stability of human PRODH2.

The PutA flavoprotein from Escherichia coli combines DNA-binding, proline dehydrogenase (PRODH), and Delta(1)-pyrroline-5-carboxylate dehydrogenase (P5CDH) activities onto a single polypeptide. Recently, an X-ray crystal structure of PutA residues 87-612 was solved which identified a D370-Y540 hydrogen bond pair in the PRODH active site that appears to have an important role in shaping proline binding and the FAD redox environment. To examine the role of D370-Y540 in the PRODH active site, mutants D370A, Y540F, and D370A/Y540F were characterized in a form of PutA containing only residues 86-601 (PutA86-601) designed to mimic the known structural region of PutA (87-612). Disruption of the D370-Y540 pair only slightly diminished k(cat), while more noticeable affects were observed in K(m). The mutant D370A/Y540F showed the most significant changes in the pH dependence of k(cat)/K(m) and K(m) relative to wild-type PutA86-601 with an apparent pK(a) value of about 8.2 for the pH-dependent decrease in K(m). From the pH profile of D370A/Y540F inhibition by l-tetrahydro-2-furoic acid (l-THFA), the pH dependency of K(m) in D370A/Y540F is interpreted as resulting from the deprotonation of the proline amine in the E-S complex. Replacement of D370 and Y540 produces divergent effects on the E(m) for bound FAD. At pH 7.0, E(m) values of -0.026, -0.089 and -0.042 V were determined for the two-electron reduction of bound FAD in D370A, Y540F and D370A/Y540F, respectively. The 40-mV positive shift in E(m) determined for D370A relative to wild-type PutA86-601 (E(m)=-0.066 V, pH 7.0) indicates D370 has a key role in modulating the FAD redox environment.

The PutA flavoprotein from Escherichia coli is a transcriptional repressor and a bifunctional enzyme that regulates and catalyzes proline oxidation. PutA represses transcription of genes putA and putP by binding to the control DNA region of the put regulon. The objective of this study is to define and characterize the DNA binding domain of PutA. The DNA binding activity of PutA, a 1320 amino acid polypeptide, has been localized to N-terminal residues 1-261. After exploring a potential DNA-binding region and an N-terminal deletion mutant of PutA, residues 1-90 (PutA90) were determined to contain DNA binding activity and stabilize the dimeric structure of PutA. Cell-based transcriptional assays demonstrate that PutA90 functions as a transcriptional repressor in vivo. The dissociation constant of PutA90 with the put control DNA was estimated to be 110 nm, which is slightly higher than that of the PutA-DNA complex (K(d) approximately 45 nm). Primary and secondary structure analysis of PutA90 suggested the presence of a ribbon-helix-helix DNA binding motif in residues 1-47. To test this prediction, we purified and characterized PutA47. PutA47 is shown to purify as an apparent dimer, to exhibit in vivo transcriptional activity, and to bind specifically to the put control DNA. In gel-mobility shift assays, PutA47 was observed to bind cooperatively to the put control DNA with an overall dissociation constant of 15 nm for the PutA47-DNA complex. Thus, N-terminal residues 1-47 are critical for DNA-binding and the dimeric structure of PutA. These results are consistent with the ribbon-helix-helix family of transcription factors.

This study examined diagnostic efficiency of Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV), criteria for borderline personality disorder (BPD). One hundred thirty monolingual Hispanic adults (90 men, 40 women) at an outpatient psychiatric and substance abuse clinic were assessed with the Spanish-Language Version of the Diagnostic Interview for DSM-IV Personality Disorders (C. M. Grilo, L. M. Anez, & T. H. McGlashan, 2003). The BPD diagnosis was determined by the best-estimate method. Diagnostic efficiency indices were calculated for all BPD criteria, for the entire study group, and separately by gender. Overall, the best exclusion criterion was affective instability, whereas suicidality or self-injury was the best inclusion criterion and the best predictor overall. These findings did not differ by gender, are similar to those reported elsewhere in the literature, and have implications for the refinement of diagnostic systems.

The regulation of proline utilization in Escherichia coli involves the proline-dependent translocation of the PutA flavoprotein from the cytoplasm to a peripheral position on the membrane. In the cytoplasm, PutA represses transcription of the proline utilization (put) genes while membrane-bound PutA catalyzes the oxidation of L-proline to glutamate. The mechanism by which PutA switches from a DNA-binding protein to a membrane-bound enzyme involves a proline-induced conformational change that is characterized by the appearance of a 119-kDa fragment during limited proteolysis of proline-reduced PutA. To establish whether the FAD redox state is responsible for the proline-induced conformational change in PutA, we distinguished the effects that FAD reduction and proline analogue binding have on PutA conformation by limited chymotrypsin proteolysis. Controlled potentiometric proteolysis of PutA demonstrated that the formation of the 119-kDa band occurs at an E(m)(conf) value of -0.058 V (pH 7.5), which is within 20 mV of the E(m) value for FAD bound to PutA. The manipulation of the E(m)(conf) value by reconstitution of PutA with the FAD analogue, 5-deazaFAD, confirmed that the conformational change observed in the presence of proline is solely dependent on the FAD redox state. The proline analogue, L-tetrahydro-2-furoic acid (L-THFA), failed to elicit the formation of the 119-kDa fragment during chymotrypsin cleavage of PutA. Instead, a unique fragment of about 93-kDa was observed, indicating that a distinct PutA conformer is stabilized by L-THFA. Reduction of L-THFA-complexed PutA, however, regenerated the 119-kDa fragment showing that reduction of the FAD cofactor overrides conformational changes induced by L-THFA. Mapping of the protease susceptibility sites in PutA revealed that the conformational changes caused by FAD reduction and L-THFA binding are transmitted to domains outside the proline dehydrogenase active site.

The PutA flavoprotein from Escherichia coli plays multiple roles in proline catabolism by functioning as a membrane-associated bi-functional enzyme and a transcriptional repressor of proline utilization genes. The human homolog of the PutA proline dehydrogenase (PRODH) domain is critical in p53-mediated apoptosis and schizophrenia. Here we report the crystal structure of a 669-residue truncated form of PutA that shows both PRODH and DNA-binding activities, representing the first structure of a PutA protein and a PRODH enzyme from any organism. The structure is a domain-swapped dimer with each subunit comprising three domains: a helical dimerization arm, a 120-residue domain containing a three-helix bundle similar to that in the helix-turn-helix superfamily of DNA-binding proteins and a beta/alpha-barrel PRODH domain with a bound lactate inhibitor. Analysis of the structure provides insight into the mechanism of proline oxidation to pyrroline-5-carboxylate, and functional studies of a mutant protein suggest that the DNA-binding domain is located within the N-terminal 261 residues of E. coli PutA.

Objective: The authors examined the diagnostic efficiency of borderline personality disorder criteria in adolescent inpatients. For comparison, diagnostic efficiency of borderline personality disorder criteria was also examined in a group of concurrently recruited adult inpatients., Method: Adolescents (N=123) and adults (N=106) were reliably assessed with the Personality Disorder Examination, a semistructured diagnostic interview for DSM-III-R personality disorders. Sixty-five adolescents and 50 adults met diagnostic criteria for borderline personality disorder. Conditional probabilities were calculated to determine which borderline personality disorder criteria were most efficient as inclusion criteria and as exclusion criteria. Adolescents and adults were analyzed separately, and the results were compared., Results: There were no significant differences between groups with regard to the base rates of the borderline personality disorder diagnosis nor for any borderline personality disorder criterion. The best inclusion criterion for the adolescents was abandonment fears, though for the adults all symptoms were approximately equivalent in this regard. The most efficient exclusion criterion was uncontrolled anger for the adolescents and impulsiveness for the adults., Conclusions: In hospitalized patients, borderline personality disorder and its symptoms appear to be as frequent for adolescents as for adults. Despite these surface similarities between groups with respect to symptom patterns, several differences were found at the level of the diagnostic efficiency for individual borderline personality disorder criteria. These differences may shed light on the nature of borderline psychopathology during adolescence.

The PutA flavoprotein regulates proline metabolism in Escherichia coli by performing two distinct functions. First, in the cytoplasm, PutA represses transcription of the put (proline utilization) regulon. Second, PutA associates with the membrane to oxidize proline to glutamate using discrete proline dehydrogenase and Delta(1)-pyrroline-5-carboxylate dehydrogenase domains. Here, we identify a proline analog that will be useful for testing the role substrate binding has in regulating PutA functions. L-Tetrahydro-2-furoic acid (L-THFA) was found to display simple competitive inhibition of proline dehydrogenase activity in PutA (apparent K(i)=0.2mM) and to perturb the flavin adenine dinucleotide (FAD) absorbance spectrum upon complexation to PutA. At pH 7.5, a reduction potential (E(m)) of -0.089V for the FAD/FADH(2) couple in L-THFA-complexed PutA was determined by potentiometric titrations. The E(m) value for L-THFA-complexed PutA is 12mV more negative than the E(m) for uncomplexed PutA (E(m)=-0.077V, pH 7.5) and corresponds to just a twofold increase in the dissociation constant of L-THFA with PutA upon reduction of FAD.

The multifunctional PutA flavoprotein from Escherichia coli is a peripherally membrane-bound enzyme that has both proline dehydrogenase (PDH) and Delta(1)-pyrroline-5-carboxylate dehydrogenase (P5CDH) activities. In addition to its enzymatic functions, PutA displays DNA-binding activity and represses proline catabolism by binding to the control region DNA of the put regulon (put intergenic DNA). Presently, information on structure-function relationships for PutA is derived from primary structure analysis. To gain further insight into the functional organization of PutA, our objective is to dissect PutA into different domains and to characterize them separately. Here, we report the characterization of a bifunctional proline dehydrogenase (PutA(669)) that contains residues 1-669 of the PutA protein. PutA(669) purifies as a dimer and has a PDH specific activity that is 4-fold higher than that of PutA. As anticipated, PutA(669) lacks P5CDH activity. At pH 7.5, an E(m) (E-FAD/E-FADH(-)) of -0.091 V for the two-electron reduction of PutA(669)-bound FAD was determined by potentiometric titrations, which is 15 mV more negative than the E(m) for PutA-bound FAD. The pH behavior of the E(m) for PutA(669)-bound FAD was measured in the pH range 6.5-9.0 at 25 degrees C and exhibited a 0.03 V/pH unit slope. Analysis of the DNA and membrane-binding properties of PutA(669) shows that it binds specifically to the put intergenic control DNA with a binding affinity similar to that of PutA. In contrast, we did not observe functional association of PutA(669) with membrane vesicles. We conclude that PutA(669) has FAD-binding and DNA-binding properties comparable to those of PutA but lacks a membrane-binding domain necessary for stable association with the membrane.

The PutA flavoprotein from Escherichia coli is a multifunctional protein that plays pivotal roles in proline catabolism by functioning as both a membrane-associated bifunctional enzyme and a transcriptional repressor. Peripherally membrane-bound PutA catalyzes the two-step oxidation of proline to glutamate, while cytoplasmic PutA represses the transcription of its own gene and the gene for a proline-transporter protein. X-ray crystallographic studies on PutA have been initiated to determine how the PutA structural scaffold enables it to be both an enzyme and a repressor, and to understand the mechanism by which PutA switches between its enzymatic and DNA-binding functions. To facilitate crystallization, a recombinant protein (PutA669) corresponding to the N-terminal 669 amino-acid residues of the 1320 residues of PutA was engineered. Activity assays demonstrated that PutA669 catalyzes the first step of chemistry performed by PutA, the conversion of proline to Delta1-pyrroline-5-carboxylate. Crystals of PutA669 have been obtained from PEG 3000 buffered at pH 6-7. The crystals occupy an I-centered orthorhombic lattice with unit-cell parameters a = 72.5, b = 140.2, c = 146.8 A; a 2.15 A data set was collected using a rotating-anode source. Assuming one molecule per asymmetric unit, the Matthews coefficient V(M) is 2.5 A(3) Da(-1), with a solvent content of 50%. The structure of PutA669 will be solved by multiple isomorphous replacement.

Methyl-coenzyme M reductase (MCR), the key enzyme in methanogenesis, catalyzes methane formation from methyl-coenzyme M (methyl-SCoM) and N-7-mercaptoheptanoylthreonine phosphate (CoBSH). Steady-state and presteady-state kinetics have been used to test two mechanistic models that contrast in the role of CoBSH in the MCR-catalyzed reaction. In class 1 mechanisms, CoBSH is integrally involved in methane formation and in C-S (methyl-SCoM) bond cleavage. On the other hand, in class 2 mechanisms, methane is formed in the absence of CoBSH, which functions to regenerate active MCR after methane is released. Steady-state kinetic studies are most consistent with a ternary complex mechanism in which CoBSH binds before methane is formed, as found earlier [Bonacker et al. (1993) Eur. J. Biochem. 217, 587-595]. Presteady-state kinetic experiments at high MCR concentrations are complicated by the presence of tightly bound CoBSH in the purified enzyme. Chemical quench studies in which (14)CH(3)-SCoM is rapidly reacted with active MCRred1 in the presence versus the absence of added CoBSH indicate that CoBSH is required for a single-turnover of methyl-SCoM to methane. Similar single turnover studies using a CoBSH analogue leads to the same conclusion. The results are consistent with class 1 mechanisms in which CoBSH is integrally involved in methane formation and in C-S (methyl-SCoM) bond cleavage and are inconsistent with class 2 mechanisms in which CoBSH binds after methane is formed. These are the first reported pre-steady-state kinetic studies of MCR.

We examined the stability of DSM-III-R personality disorder dimensions in a clinical sample of adolescents. Sixty adolescent inpatients were reliably assessed with the Personality Disorder Examination (PDE) soon after admission to the Yale Psychiatric Institute, and were independently reassessed with the same instrument 2 years following discharge. PDE symptom ratings were summed to create dimensional scores for each personality disorder. To assess the dimensional stability of personality disorders, intraclass correlation coefficients (ICCs) were computed. To assess the magnitude of the difference between baseline and follow-up scores, paired t tests were used. Significant ICCs were observed for histrionic, narcissistic, dependent, obsessive-compulsive, and passive-aggressive personality disorders. Compared to baseline, dimensional scores for most personality disorders were significantly lower at follow-up-and none was significantly higher. Diagnostic stability is a key defining feature of personality disorders. We observed low-to-moderate stability for dimensional measures of personality dysfunction in adolescents-suggesting that previous reports of modest personality disorder stability in this age group cannot be attributed solely to limitations of the categorical approach to such pathology. Alternatively, our findings may be viewed as consistent with reports in the adult literature that personality disorders may improve over time, and can potentially benefit from treatment., (Copyright 2001 by W.B. Saunders Company)

The effects of aromatic stacking interactions on the stabilization of reduced flavin adenine dinucleotide (FAD) and substrate/product have been investigated in short-chain acyl-coenzyme A dehydrogenase (SCAD) from Megasphaera elsdenii. Mutations were made at the aromatic residues Phe160 and Tyr366, which flank either face of the noncovalently bound flavin cofactor. The electrochemical properties of the mutants were then measured in the presence and absence of a butyryl-CoA/crotonyl-CoA mixture. Results from these redox studies suggest that the phenylalanine and tyrosine both engage in favorable pi-sigma interactions with the isoalloxazine ring of the flavin to help stabilize formation of the anionic flavin hydroquinone. Disruption of these interactions by replacing either residue with a leucine (F160L and Y366L) causes the midpoint potential for the oxidized/hydroquinone couple (E(ox/hq)) to shift negative by 44-54 mV. The E(ox/hq) value was also found to decrease when aromatic residues containing electron-donating heteroatoms were introduced at the 160 position. Potential shifts of -32 and -43 mV for the F160Y and F160W mutants, respectively, are attributed to increased pi-pi repulsive interactions between the ring systems. This study also provides evidence for thermodynamic regulation of the substrate/product couple in the active site of SCAD. Binding to the wild-type enzyme caused the midpoint potential for the butyryl-CoA/crotonyl-CoA couple (E(BCoA/CCoA)) to shift 14 mV negative, stabilizing the oxidized product. Formation of product was found to be even more favorable in complexes with the F160Y and F160W mutants, suggesting that the electrostatic environment around the flavin plays a role in substrate/product activation.

We examined internal consistency and criterion overlap of DSM-III-R personality disorder criteria in late adolescence, 2 years after psychiatric hospitalization. A total of 60 adolescents were assessed with the Personality Disorder Examination. Within-category cohesiveness (internal consistency) was evaluated by coefficient alpha and mean intercriterion correlation (MIC). Between-category criterion overlap was evaluated by examining intercategory mean intercriterion correlations (ICMIC) between all pairs of disorders. Internal consistency was low, with alpha less than .70 for all except borderline and dependent personality disorders. For most disorders, MIC values were higher than ICMIC values. Our findings suggest that personality disorder criteria sets have limited internal consistency in older adolescents. Although the criteria for most personality disorders correlate better with each other than with the criteria for other personality disorders, suggesting some degree of discriminant validity, comparison of these results with a similar analysis performed shortly after hospital admission raises questions about personality disorder construct validity during adolescence.

The PutA flavoprotein from Escherichia coli is both a transcriptional repressor and a membrane-associated proline dehydrogenase. PutA represses transcription of the putA and putP genes by binding to the control region DNA of the put regulon (put intergenic DNA). Previous work has shown that FAD has a role in regulating the transcriptional repressor and membrane binding functions of the PutA protein. To test the influence of the FAD redox state on PutA--DNA interactions, we characterized the redox properties of the PutA flavoprotein from E. coli. At pH 7.5, an E(m)(E--FAD/E--FADH(2)) of --0.076 V for the two-electron reduction of PutA-bound FAD was determined by potentiometric titrations. Stabilization of semiquinone species was not observed during potentiometric measurements. Dithionite reduction of PutA, however, caused formation of red anionic semiquinone. The E(m) value for the proline/Delta(1)-pyrroline-5-carboxylate couple was determined to be --0.123 V, demonstrating the reduction of PutA by proline is favored by a potential difference (Delta E degrees ') of more than 0.045 V. Characterization of the PutA redox properties in the presence of put intergenic DNA revealed an E(m)(E(DNA)--FAD/E(DNA)--FADH(2)) of --0.086 V. The 10 mV negative shift in E(m) corresponds to just a 2.3-fold increase in the dissociation constant of PutA with the DNA upon reduction of FAD. Thus, it appears the FAD redox state has little influence on the overall PutA--DNA interactions.

Objective: The authors investigated the concurrent and predictive validity of the DSM-III-R diagnosis of personality disorder in adolescents by means of baseline and follow-up assessments of inpatients treated at the Yale Psychiatric Institute., Method: One hundred sixty-five hospitalized adolescents were reliably assessed by using a structured interview for personality disorder diagnoses as well as two measures of impairment and distress--the Global Assessment of Functioning Scale and the SCL-90-R. Two years after initial assessment, 101 subjects were independently reassessed with the same measures; their functioning was also assessed at this time., Results: At baseline, adolescents with personality disorders were significantly more impaired than those without personality disorders. At follow-up, adolescents with a personality disorder diagnosis at baseline had used significantly more drugs and had required more inpatient treatment during the follow-up interval. Over time, the scores on the Global Assessment of Functioning Scale and SCL-90-R of adolescents diagnosed with a personality disorder at baseline became more similar to the scores of adolescents without a personality disorder., Conclusions: The diagnosis of personality disorder in adolescent inpatients has good concurrent validity; however, the predictive validity of the diagnosis is mixed.

Objective: The authors describe the psychiatric sequelae of "ethnic cleansing" in adolescent Bosnian refugees, via a 1-year follow-up study., Method: Ten Bosnian adolescent refugees from the war in Bosnia-Herzegovina received a baseline assessment within the first year after their resettlement and a follow-up assessment 1 year later. Evaluations included an assessment scale for posttraumatic stress disorder (PTSD) symptom severity., Results: At baseline, 3 subjects met criteria for PTSD. At follow-up, this diagnosis persisted in none of these subjects, though 1 subject met criteria at follow-up only. For the group, mean PTSD severity scores at baseline and at follow-up were 8.9 and 4.0, respectively. At baseline, reexperiencing symptoms were present 43% of the time, avoidance symptoms were present 33% of the time, and hyperarousal symptoms were present 33% of the time; at follow-up, these proportions were 35%, 16%, and 18%, respectively., Conclusions: Overall, rates of PTSD symptoms diminished during the 1-year follow-up interval, suggesting that they may be transient and not representative of enduring psychopathology. This finding may reflect the relative resiliency of adolescents, as well as a variety of factors that facilitated adaptation in our particular group of adolescent refugees.

Objective: The authors examined the applicability of personality disorder criteria to adolescent inpatients by evaluating internal consistency and criterion overlap., Method: Thirty-eight adolescents and 28 adults were assessed with the Personality Disorder Examination. Within-category cohesiveness (internal consistency) of the criteria was evaluated by examining intercriterion correlations as well as coefficient alpha. In addition, between-category criterion overlap was evaluated by examining "intercategory" intercriterion correlations between all pairs of disorders. Separate analyses were conducted for adolescents and adults, and the groups were compared., Results: Internal consistency appeared to be lower in adolescents, as measured by intercriterion correlation and coefficient alpha, with the largest differences being identified for most cluster B disorders. Intercategory analysis indicated that criterion overlap may be greater among adolescents., Conclusions: Overall, this psychometric analysis suggests that there may be limitations to the DSMs approach to categorizing personality disorders. For both adolescents and adults, modest degrees of within-category cohesiveness (internal consistency) and between-category criterion overlap were observed. Comparatively, personality disorder criteria in adolescents tended to have lower internal consistency and less discriminant validity. The data raise questions about the construct validity of these disorders--or the applicability of these criteria--within this age group.

Nucleotide excision repair, a general repair mechanism for removing DNA damage, is initiated by dual incisions bracketing the lesion. In procaryotes, the dual incisions result in excision of the damage in 12- to 13-nucleotide-long oligomers, and in eucaryotes they result in excision of the damage in the form of 24- to 32-nucleotide-long oligomers. We wished to find out if Archaea perform excision repair. Using cell extracts from Methanobacterium thermoautotrophicum, we found that this organism removes UV-induced (6-4) photoproducts in the form of 10- to 11-mers by incising the sixth to seventh phosphodiester bond 5' to the damage and the fourth phosphodiester bond 3' to the damage.

An iron-sulfur flavoprotein (Isf) from the methanoarchaeaon Methanosarcina thermophila, which participates in electron transfer reactions required for the fermentation of acetate to methane, was characterized by electrochemistry and EPR and Mössbauer spectroscopy. The midpoint potential (Em) of the FMN/FMNH2 couple was -0.277 V. No flavin semiquinone was observed during potentiometric titrations; however, low amounts of the radical were observed when Isf was quickly frozen after reaction with CO and the CO dehydrogenase/acetyl-CoA synthase complex from M. thermophila. Isf contained a [4Fe-4S]2+/1+ cluster with g values of 2.06 and 1.93 and an unusual split signal with g values at 1.86 and 1.82. The unusual morphology was attributed to microheterogeneity among Isf molecules. The Em value for the 2+/1+ redox couple of the cluster was -0.394 V. Extracts from H2-CO2-grown Methanobacterium thermoautotrophicum cells catalyzed either the H2- or CO-dependent reduction of M. thermophila Isf. In addition, Isf homologs were found in the genomic sequences of the CO2-reducing methanoarchaea M. thermoautotrophicum and Methanococcus jannaschii. These results support a general role for Isf in electron transfer reactions of both acetate-fermenting and CO2-reducing methanoarchaea. It is suggested that Isf functions to couple electron transfer from ferredoxin to membrane-bound electron carriers, such as methanophenazine and/or b-type cytochromes.

Objective: The authors' goal was to describe the characteristics of posttraumatic stress disorder (PTSD) symptoms on resettlement in the United States and at 1-year follow-up among Bosnian refugees as well as possible factors affecting the PTSD symptom profile among these refugees., Method: They used standardized instruments to assess 34 Bosnian refugees for PTSD at resettlement in the United States and 1 year later., Results: Fifteen of the refugees were diagnosed with PTSD at 1-year follow-up, compared with 25 at initial assessment. The average PTSD severity score at follow-up was 12.5, compared with 20.6 at initial assessment. At 1-year follow-up, 25 of the refugees experienced a decrease in severity of PTSD symptoms, one remained the same, and eight experienced an increase in severity. Older refugees were significantly more likely to have PTSD than younger refugees, and older refugees had more severe symptoms., Conclusions: The level of PTSD diagnosis and symptoms in Bosnian refugees remained substantial 1 year after their resettlement in the United States, although there were notable overall decreases. Older refugees appeared to be at greater risk.

Here, we report a method to generate the active form of methyl-SCoM reductase (MCR) from Methanosarcina thermophila. The protocol involves adding sodium sulfide to a growing cell culture prior to harvest to yield a "ready" (MCRox1) state of the enzyme. This method can also generate a ready state of the Methanobacterium thermoautotrophicum (strain Marburg) MCR. Experiments using sodium 35S-labeled sulfide indicate the ready state that is generated involves a Ni-S adduct. As was shown earlier for the Mb. thermoautotrophicum MCRox1 [Goubeaud, M., Schreiner, G. and Thauer, R. K. (1997) Eur. J. Biochem. 17, 2374-2377], this ready state is converted to the highly active MCRred1 form by reductive activation with Ti(III) citrate. The reduction of MCRox1 to MCRred1 with concomitant increase in activity demonstrated that MCRred1 is the active form of MCR from Ms. thermophila. We also observed the loss of the 35S-sulfide label from the enzyme when MCRox1 was converted to MCRred1. Other states of MCR could be generated in the whole cells by adding different potential ligands to the cell medium; for example, the MCRox2 state was generated by treating cells with sodium sulfite or sodium dithionite.

The authors used the SCID-DES (disorders of extreme stress) instrument to assess for personality change in Bosnian survivors of "ethnic cleansing." Twenty four refugees underwent systematic, trauma-focused, research assessments, including the SCID-DES interview. Overall, this group of Bosnian survivors had been severely traumatized as a result of the Serbian nationalists' genocide. However, no subject met diagnostic criteria for DES. The SCID-DES yields far lower rates of trauma-related personality change in Bosnian survivors of genocide than in adult survivors of prolonged early life traumas. Therefore, the DES construct may have better application to prolonged, interpersonal, early life traumas than to the prolonged, communal traumas of genocide.

Objective: The purpose of this study was to examine DSM-III-R axis I and axis II comorbidity in psychiatrically hospitalized young adults with substance use disorders., Method: Structured diagnostic interviews were given to 117 consecutive inpatients. Seventy patients with substance use disorders and 47 patients without substance use disorders were compared., Results: High rates of co-occurrence of axis I disorders were observed, but no disorder coexisted in the group with substance use disorders at a significantly higher rate than in the group without substance use disorders. Among axis II disorders, borderline personality disorder was diagnosed significantly more frequently in the group with substance use disorders., Conclusions: Significant additional diagnostic co-occurrence, defined as comorbidity, was observed only between borderline personality disorder and substance use disorders. The use of a relevant psychiatric comparison group allows for finer distinctions between covariation based on shared severity and comorbidity possibly based on shared pathophysiology.

To examine gender differences in the co-occurrence of DSM-III-R axis I disorders and axis II personality disorders in young adult psychiatric inpatients with substance use disorders (SUDs), a consecutive series of 70 inpatients (33 men and 37 women) with SUD were reliably assessed with structured diagnostic interviews. Higher rates of dysthymia and eating disorders were observed in SUD females and higher rates of cluster A personality disorders were observed in SUD males. No gender differences were found for depression or anxiety in our SUD inpatients; these findings contrast with gender ratios for these disorders in the general population. In conclusion, relatively few gender differences were found in young adult inpatients with SUD, even where they would be expected based on general population gender patterns.

We compared the diagnostic comorbidity of DSM-III-R axis I and axis II disorders in a sample of hospitalized adolescents with conduct disorder (CD) and a comparison group of hospitalized adolescents without conduct disorder (non-CD). Of 138 consecutively evaluated adolescents, 76 patients met criteria for CD and 62 did not. On axis I, CD was significantly comorbid with attention-deficit hyperactivity disorder (ADHD) and substance use disorders (SUDs). None of the personality disorders assessed showed differential association with CD. The comorbid relationships found within this sample suggest a strong association between CD, ADHD, and SUD in hospitalized teenagers. This finding underscores the clinical importance of conducting a thorough developmental assessment and, when indicated, of treating ADHD and SUD in conduct-disordered adolescents.

The authors describe the prevalence of childhood traumatic experiences among adolescent inpatients. A Childhood Trauma Chart Review Scale (CTCRS) was developed to assess traumatic experiences during childhood and adolescence. The CTCRS was reliably applied to the medical records of 75 adolescent inpatients who had been given structured clinical interviews for DSM-III-R diagnoses at the time of admission. Most subjects (81%) had experienced at least one traumatic event during childhood, with loss of caregiver being the most frequent type of traumatic experience. Many subjects had multiple types of traumatic experiences, during both early and late childhood. A history of childhood trauma was associated with greater functional impairment and higher likelihood of having a personality disorder, but with no difference in Axis I diagnoses.

This study examined the presence of personality disorders in adolescent inpatients with major depression (MDD; n = 45), substance use disorders (SUD; n = 27), or both disorders combined (MDD-SUD; n = 42). A consecutive series of patients were given structured diagnostic interviews for Axes I and II disorders. The groups did not differ with regard to age, gender, ethnicity, socioeconomic status, psychiatric history, or global assessment of functioning. Borderline personality disorder was diagnosed more frequently in the MDD-SUD group than in the MDD or the SUD groups.

We examined gender differences in DSM-III-R personality disorders in psychiatrically hospitalized young adults. Structured diagnostic interviews were reliably performed on a consecutive series of 118 inpatients. Men were significantly more likely to meet criteria for cluster A, schizotypal, and antisocial personality disorders. To reduce variability due to axis I heterogeneity, we retested for gender differences in a subgroup of patients with major depression. Depressed men were more likely to meet criteria for cluster A, schizotypal, and cluster C personality disorders. Women were not observed to have a higher frequency of any personality disorder than men in either study group.

Objective: The authors examined gender differences in DSM-III-R personality disorders in adolescent psychiatric inpatients., Methods: Structured diagnostic interviews were reliably performed with a series of 138 consecutively admitted adolescent inpatients. To reduce variability due to heterogeneity of axis I diagnoses, a subgroup of 87 patients with major depression was retested for gender differences., Results: Females were significantly more likely than males to meet the criteria for borderline personality disorder. Narcissistic personality disorder was diagnosed only in males. A similar pattern was observed in the subgroup of patients with major depression., Conclusions: The findings suggest potentially important gender differences in personality disorders in adolescent inpatients.

Objective: The authors examined the association between conduct disorder and substance use disorders in adolescent inpatients., Method: Structured diagnostic interviews were given to 165 adolescent inpatients to assess the presence of DSM-III-R axis I disorders and personality disorders from axis II. Patients with conduct disorder (N = 25), substance use disorders (N = 24), and coexisting conduct and substance use disorders (N = 54) were compared to determine whether additional axis I and axis II disorders presented at significantly different rates., Results: The groups with conduct disorder and coexisting conduct and substance use disorders had a higher proportion of male subjects than the group with substance use disorders alone. Patients with conduct disorder had an earlier age at first psychiatric contact and were diagnosed significantly more often with attention deficit hyperactivity disorder than the other two groups. Borderline personality disorder was diagnosed more frequently in the patients with substance use and coexisting conduct and substance use disorders than in the patients with conduct disorder. These differential co-occurrence patterns were observed for both male and female subjects., Conclusions: Conduct disorder and substance use disorders have high comorbidity rates with other psychiatric disorders in adolescent inpatients. The additional psychiatric comparison group (patients with coexisting conduct and substance use disorders) allowed for finer distinctions regarding psychiatric comorbidity. The validity of subtyping conduct disorder on the basis of the presence of a coexisting substance use disorder is suggested; conduct disorder patients without a coexisting substance use disorder are more likely to have attention deficit hyperactivity disorder.

Structured diagnostic interviews were used to determine DSM-III-R axis I and II diagnoses among 136 female psychiatric inpatients. To distinguish comorbidity of eating disorders with axis I and II disorders from simple diagnostic overlap, the frequency and distribution of diagnoses among the 31 patients with an eating disorder and the 105 without an eating disorder were compared. Social phobia, substance use disorders, borderline personality disorder, and avoidant personality disorder were diagnosed in a significantly larger proportion of the group with eating disorders. Future studies should focus on interpreting the meaning of the co-occurrence of these disorders in patients with eating disorders.

Objective: To describe the psychiatric assessments and trauma testimonies of 12 Bosnian adolescents newly resettled in America., Method: Twelve Bosnian adolescents who experienced the massive psychic trauma of "ethnic cleansing" were assessed during the first year after their resettlement in the United States. Assessments consisted of systematic, trauma-focused, clinical interviews that included standard assessment scales of posttraumatic stress disorder (PTSD) and depression, as well as the opportunity to give testimony about their experiences., Results: PTSD was diagnosed in 25% of subjects and depressive disorders in 17%. Reexperiencing cluster symptoms were present in 50%, avoidance cluster symptoms in 31%, and hyperarousal cluster symptoms in 29%., Conclusions: The relatively low rate of PTSD in this sample (in comparison with adult survivors of "ethnic cleansing" and with Cambodian adolescent survivors) may be attributable to normal prior development, time-limited adversity, lack of physical or sexual traumas, rejoining nuclear families, or insufficient time for the development of delayed-onset PTSD. It may also be a reflection of the resiliency of adolescence.

Objective: To assess DSM-III-R Axis I and Axis II co-occurrence and comorbidity in adolescent inpatients with substance use disorders (SUD)., Method: A consecutive series of 138 adolescent inpatients were reliably assessed with structured diagnostic interviews for Axis I disorders and Axis II personality disorders. To determine significant co-occurrence of diagnoses, comparisons were between 69 patients with SUD and 69 patients without SUD., Results: Disruptive behavior disorders were diagnosed significantly more frequently in patients with SUD than in those without SUD. Conduct disorder was diagnosed more frequently and oppositional defiant disorder was diagnosed less frequently in the SUD patients than in the non-SUD patients. Anxiety disorders were diagnosed less frequently in the SUD group. Cluster B personality disorders and borderline personality disorder were diagnosed more frequently in the SUD group., Conclusions: The findings replicate previous research showing high rates of co-occurrence of other psychiatric disorders in adolescent inpatients with SUD. The use of a relevant psychiatric comparison group allows for finer distinctions regarding significant comorbidity and the psychopathological implications thereof.

We assessed the co-occurrence of DSM-III-R axis I and II disorders and self-reported psychologic distress in inpatients with eating disorders with and without substance use disorders (ED-SUD and ED groups, respectively) and in a matched comparison sample with substance use disorders but no eating disorder (SUD group). The three groups showed similar distributions of axis I disorders but differed in the distribution of axis II disorders. Cluster B personality disorders were diagnosed more frequently in SUD and ED-SUD groups than in the ED group. In contrast, cluster C personality disorders were diagnosed more frequently in the ED group than in SUD and ED-SUD groups. The SUD group reported greater psychologic distress than ED and ED-SUD groups. Possible implications of the observed group differences for psychologic models of why these disorders may be associated are considered.

Objective: The authors examined the stability of DSM-III-R disorders and groups of disorders in adolescent inpatients followed up 2 years after hospitalization., Method: Seventy hospitalized adolescents were reliably assessed by using structured diagnostic interviews for DSM-III-R disorders. Two years later the subjects were independently assessed with the same interviews. Diagnostic stability was measured by determining both the percentage of persisting cases and the kappa statistic., Results: Internalizing disorders had the highest percentage of persisting cases (59%) but an insignificant kappa due to many new cases at follow-up. Externalizing disorders had a lower percentage of stable cases (39%) but a significant kappa because of fewer new cases. Substance use disorders were fairly stable (53%) and had a significant kappa, indicating that this may be the most stable group of disorders in adolescents. Personality disorder clusters were relatively unstable, especially clusters A and C., Conclusions: Diagnostic stability in these hospitalized adolescents was less than that reported for adults. This may indicate that DSM-III-R diagnoses in adolescents have poor construct validity, but it may also reflect the different paths for development of psychopathology during adolescence. For axis I, externalizing disorders appear most specific to adolescence, with some persistence but decreasing incidence over time. Existing cases of internalizing disorders tend to be even more persistent, but the high incidence of new cases during adolescence contributes to lower overall stability. Substance use disorders appear to be most stable, and personality disorders appear to be least stable, in adolescents.

Objective: The authors describe the psychiatric assessments and trauma testimonies of 20 Bosnian refugees of "ethnic cleansing" who have recently resettled in the United States., Method: Refugees referred from agencies managing refugee resettlement underwent systematic, trauma-focused, clinical interviews that included standardized assessment scales., Results: The traumatic experiences of ethnic cleansing in these Bosnian refugees were genocidal in nature. The number of types of traumatic experiences correlated positively with age. Posttraumatic stress disorder (PTSD) was diagnosed in 65% of the refugees, and depressive disorders in 35%. PTSD severity scores were correlated with the number of types of traumatic events experienced., Conclusions: Ethnic cleansing has caused high rates of PTSD and depression, as well as other forms of psychological morbidity, in this group of resettled Bosnian refugees. The longitudinal sequelae of ethnic cleansing as a form of massive psychic trauma remain to be studied.

This study assessed the relationship between substance use disorders and eating disorders in female psychiatric inpatients. Structured diagnostic interviews were reliably administered to a series of inpatients with substance use disorders (n = 67) and a comparison sample without substance use disorders (n = 69). Eating disorder diagnoses as a whole, including eating disorder not otherwise specified, were distributed significantly more frequently among subjects with substance use disorders than among psychiatric controls. Frequencies of the specific diagnoses of bulimia nervosa and anorexia nervosa, however, did not differ significantly between groups. The results suggest that eating disorder features may be overrepresented among female inpatients with substance use disorders.

Previous work has shown that the redox properties of Megasphaera elsdenii short-chain acyl-CoA dehydrogenase (SCAD) are specifically modulated upon the binding of the substrate/product couple, allowing the reaction to proceed thermodynamically [Stankovich, M.T., & Soltysik, S. (1987) Biochemistry 26, 2627-2632]. The focus of this study on the Glu367Gln SCAD mutant protein is to gain an understanding of this phenomenon. The active-site mutant Glu367Gln SCAD inactivates the reductive and oxidative pathways and allows the effects of substrate (butyryl-CoA) and product (crotonyl-CoA) binding on the redox properties of the Glu367Gln SCAD mutant protein to be determined separately. Red anionic semiquinone was found to be thermodynamically stabilized in coulometric/potentiometric reductions of both butyryl-CoA- and crotonyl-CoA-complexed Glu367Gln SCAD. Reduction potential measurements showed that butyryl-CoA binding has little effect on the reduction potential of Glu367Gln SCAD. Crotonyl-CoA complexation, however, shifted the reduction potential of the Glu367Gln SCAD mutant protein by 30 mV in the positive direction. This modulation is similar to the 60-mV positive shift observed in native M. elsdenii SCAD upon complexation with the substrate/product couple [Stankovich, M.T., & Soltysik, S. (1987) Biochemistry 26, 2627-2632]. Thus, product binding and not substrate binding, thermodynamically regulates M. elsdenii SCAD. We propose that this observation is best explained by assuming that the product resembles an intermediate in the catalytic mechanism that is responsible for facilitating isopotential electron transfer from the substrate to the enzyme.

The objective of this work is to determine the molecular mechanism and regulation of short-chain acyl-CoA dehydrogenase (SCAD) from Megasphaera elsdenii. To achieve this, the gene coding for SCAD from M. elsdenii was cloned and sequenced. Site-directed mutagenesis was then used to identify an amino acid residue that is required for the proposed mechanism. To clone the gene, the amino acid sequence of the 50 N-terminal residues of SCAD from M. elsdenii was determined. This sequence information was utilized to synthesize two sets of mixed oligonucleotide primers which were then used to generate a 120-bp specific probe from M. elsdenii DNA by the polymerase chain reaction (PCR) method. The 120-bp probe was used to screen a M. elsdenii genomic DNA library cloned into Escherichia coli. The gene encoding M. elsdenii SCAD was identified from this library, sequenced, and expressed. The cloned SCAD gene contained an open reading frame which revealed a high degree of sequence identity with an open reading frame protein sequence of the human SCAD and the rat medium-chain acyl-CoA dehydrogenase (MCAD) (44% and 36% identical residues in paired comparisons for human SCAD and rat MCAD, respectively). Recombinant SCAD expressed from a pUC119 vector accounted for 35% of the cytosolic protein in the Escherichia coli crude extract. The expressed protein had similar activity, redox potential properties, and nearly identical amino acid composition to native M. elsdenii SCAD. In addition, a site-directed Glu367 Gln mutant of SCAD expressed from a pUC119 vector was shown to have minimal reductive and oxidative pathway activity with butyryl-CoA and crotonyl-CoA, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: The authors studied the hemispheric functioning of adolescents with attention-deficit hyperactivity disorder (ADHD) in relation to this group's response to positively toned emotional stimuli., Method: Dichotic word tests were used to measure perceptual asymmetry in 21 adolescent inpatients and 24 control subjects. Ten patients had ADHD; 11 did not. Subjects were tested under four emotional conditions by using combinations of neutral, positive, and negative words., Results: the ADHD group had lower right ear advantage (REA) scores when presented with stimulus pairs containing positive words than when presented with pairs not containing positive words. By comparison, the non-ADHD patient group and the control group had higher REA scores under positive emotional conditions than under non-positive conditions., Conclusions: The abnormal response to positive emotional tone supports the reward system dysfunction hypothesis of ADHD and may also have implications for learning problems, behavioral difficulties, and disturbed interpersonal relationships in this population.