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L Laporte

Publications and source records attributed to L Laporte.

12 recordsLinked to original sources
PubMed2001

Abusive relationships in families of women with borderline personality disorder, anorexia nervosa and a control group.

In a group of intact families, we examined the rates and parameters of verbal, physical, and sexual abuse in 35 women with borderline personality disorder (BPD), 34 women with anorexia nervosa (AN), and 33 women without a clinical history (NC); their experience of multiple abuse and its correlation with their SCL-90-R scores; and their reports of abuse of their siblings. Corroboration of abuse was obtained from some parents in each group. Women with BPD suffered more intrafamilial verbal and physical abuse. Whereas AN and NC women experienced relatively rare single events of extrafamilial sexual abuse at an older age, those with BPD suffered repeated intrafamilial sexual abuse at a younger age and also suffered more multiple abuse. All multiply abused women had more psychopathology. Siblings were reported abused in the same proportions as subjects; many parents of BPDs corroborated their daughters' reports of all three forms of abuse.

Adolescent↗
PubMed2000

Empathy in families of women with borderline personality disorder, anorexia nervosa, and a control group.

This is a study of empathy in the families of 27 women with borderline personality disorder (BPD), 28 women with restricting anorexia nervosa (AN), and 27 women without a clinical diagnosis (NC). The daughters and both parents responded to the Interpersonal Reactivity Index (IRI), an instrument for assessing four dimensions of empathy. In addition, they were personally interviewed, with the Family Interview for Protectiveness and Empathy (FIPE), about the extent of empathy expressed by the parents to their daughter during her development. On the IRI, women with BPD scored highest on the immature and lowest on the mature aspects of empathy, whereas scores of AN and NC women were all within normal limits. Parents of BPDs had the lowest IRI scores, while parents of AN and NC groups were similar to each other and to criterion group scores. IRI scores of AN daughters were positively correlated with their parents' scores whereas BPDs' scores were negatively correlated with those of their parents. There were no correlations between the IRI scores of NC subjects and their parents. On the FIPE, borderline daughters and parents agreed about the relative absence of empathic parenting, whereas AN and NC daughters and parents agreed as to the presence of empathic parenting. The theoretical and clinical implications of these contrasting findings are discussed.

Adolescent↗
PubMed1999

Molecular mechanism of DNA recognition by the alpha subunit of the Oxytricha telomere binding protein.

Interactions between telomeric DNA and the alpha subunit of the heterodimeric telomere binding protein of Oxytricha nova have been probed by Raman spectroscopy, CD spectroscopy, and nondenaturing gel electrophoresis. Telomeric sequences investigated include the Oxytricha 3' overhang, d(T4G4)2, and the related sequence dT6(T4G4)2, which incorporates a 5'-thymidylate leader. Corresponding nontelomeric isomers, d(TG)8 and dT6(TG)8, have also been investigated. Both d(T4G4)2 and dT6(T4G4)2 form stable hairpins that contain Hoogsteen G.G base pairs [Laporte, L., and Thomas, G. J., Jr. (1998) J. Mol. Biol. 281, 261-270]. The alpha subunit binds specifically and stoichiometrically to the dT6(T4G4)2 hairpin and alters its secondary structure by inducing conformational changes in the 5'-thymidylate leader without extensive disruption of G.G base pairing. Conversely, binding of the alpha subunit to d(T4G4)2 eliminates G.G pairing and unfolds the hairpin. DNA unfolding is accompanied by conformational changes affecting both the backbone and dG residues, as evidenced by Raman and CD spectra. Interestingly, the alpha subunit also forms complexes with the nontelomeric isomers, d(TG)8 and dT6(TG)8, evidenced by altered electrophoretic mobility in nondenaturing gels; however, Raman and CD spectra of complexes of the alpha subunit with nontelomeric DNA suggest no significant changes in backbone or deoxynucleoside conformations. Similarly, the alpha subunit binds to but does not appreciably alter the secondary structure of duplex DNA. The present results show that while the alpha subunit has the capacity to bind to Watson-Crick and different non-Watson-Crick motifs, DNA refolding is specific to the Oxytricha telomeric hairpin and the retention of G.G pairing is specific to the telomeric sequence incorporating the 5' leading sequence. A model is proposed for alpha subunit binding to telomeric DNA, and the physiological role of the alpha subunit in telomere organization is discussed.

Animals↗
PubMed1999

Paternal filicide: a study of 10 men.

OBJECTIVE: To describe the psychiatric and sociodemographic profiles of 10 men who killed 1 or more of their children. METHOD: Data were gathered from psychiatric, psychological, and criminological assessments found in the files of 10 filicidal men hospitalized at the Institut Philippe Pinel de Montréal between 1982 and 1994. RESULTS: Many situational factors were present during the period preceding the offence (such as the possibility of a separation or financial problems). Most of these homicides have been classified as pathological filicides. At the time of the offence, the most frequent diagnoses were mood disorders. Eight subjects had personality disorders, one-half of which were borderline personality disorders. Four men had psychotic symptoms at the time of the offence. Six of the 10 men also killed or attempted to kill their spouses. CONCLUSION: Many factors are involved in the dynamics of a filicidal situation. It is therefore difficult to identify specific warning signals for the prevention of this type of homicide. However, mental health professionals and the general population must be made aware of the importance of early assessment of possible filicidal tendencies when a man verbalizes delusional ideas about his child and/or if he manifests disorganized and bizarre behaviour.

Adolescent↗
PubMed1998

A hairpin conformation for the 3' overhang of Oxytricha nova telomeric DNA.

The solution secondary structure of the Oxytricha nova telomeric 3' overhang, d(T4G4)2, has been investigated by Raman spectroscopy, hydrogen-deuterium exchange kinetics and gel electrophoresis. The electrophoretic mobility of d(T4G4)2 in non-denaturing gels indicates a highly compact conformation, consistent with a hairpin secondary structure. Raman markers show that the d(T4G4)2 hairpin contains equal numbers of C2'-endo/syn and C2'-endo/anti deoxyguanosine conformers, as well as G.G base-pairs of the Hoogsteen type. The hydrogen-deuterium exchange kinetics of d(T4G4)2, monitored by time-resolved Raman spectroscopy, reveal two kinetically distinct classes of guanine imino (N1H) protons. The more slowly exchanging fraction (kN1H(1)=4.6x10(-3) min-1), which represents 50% of N1H groups, is attributed to Hoogsteen-paired residues. The more rapidly exchanging fraction (kN1H(2)>/=0.3 min-1) is attributable to solvent-exposed residues. Raman dynamic probe of the kinetics of guanine C8H-->C8(2)H exchange in d(T4G4)2 reveals modest retardation vis-à-vis dGMP, which rules out quadruplex formation by the telomeric repeat and confirms an ordered secondary structure consistent with a Hoogsteen-paired hairpin. Similar Raman, hydrogen-isotope exchange and electrophoretic mobility experiments on the related telomeric model, dT6(T4G4)2, also reveal a hairpin stabilized by Hoogsteen G.G pairs. Presence of the 5' thymidine tail preceding the Oxytricha telomeric repeat has no apparent effect on the hairpin secondary structure. We propose a molecular model for the hairpin conformation of the Oxytricha nova telomeric repeat and consider its possible roles in mechanisms of telomeric DNA interaction in vitro and telomere function in vivo.

Animals↗
PubMed1998

Structural basis of DNA recognition and mechanism of quadruplex formation by the beta subunit of the Oxytricha telomere binding protein.

Interactions of the beta subunit of the Oxytricha nova telomere binding protein with the telomeric DNA sequences, d(T4G4)2 and dT6(T4G4)2, have been investigated in vitro using Raman and fluorescence spectroscopies. Raman difference spectra show that the beta subunit binds to both d(T4G4)2 and dT6(T4G4)2 but promotes the formation of a parallel-stranded quadruplex only in dT6(T4G4)2, thus demonstrating the importance of the telomeric 5' tail for in vitro recognition and guanine quadruplex formation. While d(T4G4)2 is not a suitable substrate for quadruplex promotion by the beta subunit, the Raman spectra reveal other structural rearrangements of this DNA strand upon beta subunit binding, including changes in guanine glycosyl torsion angles from syn to anti and disruption of carbonyl hydrogen-bonding interactions. The conformation of d(T4G4)2 in the beta:d(T4G4)2 complex is suggested as a plausible intermediate along the pathway to formation of the parallel-stranded guanine quadruplex. Fluorescence band shifts indicate that at least one of the two tryptophans of the beta subunit is shielded from solvent as a consequence of DNA binding in both the beta:dT6(T4G4)2 and beta:d(T4G4)2 complexes. However, the Raman spectra of these complexes suggest no significant changes in the beta subunit secondary structure attendant with DNA binding. A model for beta subunit binding by Oxytricha telomeric DNA sequences and a mechanism for quadruplex formation are proposed. A key feature of this model is the use of a telomeric hairpin secondary structure as the recognition motif.

Animals↗
PubMed1997

Solution conformations and interactions of alpha and beta subunits of the Oxytricha nova telomere binding protein: investigation by Raman spectroscopy.

Solution conformations of the alpha and beta subunits of the Oxytricha nova telomere binding protein have been investigated by Raman spectroscopy. Raman spectra have also been obtained for a deletion mutant of the beta subunit, betaC232, which retains the N-terminal domain that is active in ternary complex (alpha:beta:DNA) formation but lacks the C-terminal domain that is active in catalyzing guanine quadruplex formation. The Raman spectra show that alpha, beta, and betaC232 are rich in beta-strand secondary structure ( approximately 40-50%) and turns. The Raman signature of the C-terminal 153 amino acids of beta, generated by subtracting the spectrum of betaC232 (residues 1-232) from that of the full subunit, indicates that the domain active in guanine quadruplex formation contains less beta-strand secondary structure and more irregular structure than the domain active in alpha:beta:DNA formation. Raman markers also provide information about the environments and orientations of several key side chains, including tryptophan residues in N- and C-terminal domains of the beta subunit. Both alpha and beta denature between 30 and 40 degrees C, as evidenced by large changes in Raman bands diagnostic of main chain conformation and side chain environments. The Raman spectrum of an equimolar alpha/beta mixture exhibits no evidence of specific interaction between the subunits; further, the denaturation profile of this mixture is indistinguishable from the sum of denaturation profiles of the constituent subunits, consistent with the absence of appreciable interaction between alpha and beta throughout the range 0-50 degrees C. The present results provide insights into the solution conformations of the Oxytricha telomere binding protein subunits and serve as the basis for future study of subunit interactions with telomeric DNA.

Animals↗
PubMed1995

[Infanticide committed by the mother].

Using data gathered at the Institut Philippe Pinel in Montréal, we shall describe the sociodemographic and psychiatric profile of a sample of 17 women who have killed (n = 14) or attempted to kill (n = 3) one of their children. Our data indicate that women who have committed this type of offence generally come from a disadvantaged socioeconomic environment. Most have a psychiatric history (evaluation and/or hospitalization). Review of the offence demonstrates that most women do not use a weapon to kill their child; the preferred methods are strangulation or drowning. Most of these offences may be classified as extended suicide or altruistic acts. Several of the women present with a severe personality disorder and an additional depressive episode in the context of the offence. We hope our study will help clarify understanding of filicide and assist in the development of certain prevention axes. These results indicate that the population at large and various intervenors in our society (family physicians, psychiatrists, criminologists, social workers, pediatricians, psychologists, gynecologists) must become increasingly vigilant and avoid trivialization of signals such as verbalization of homicidal thoughts about the child or recourse to certain disorganized behaviours.

Adult↗
PubMed1985

[Use of barbiturates in posttraumatic comas at the mesencephalic level. Apropos of 38 cases].

Thirty-eight patients with brain injury and mesencephalic coma, or a Glasgow score of less than 5, were treated routinely with Thiopental administered by electric syringe for a mean duration of 4 days. Follow up review criteria were based on clinical computed tomography and electroencephalographic data, as well as results of monitoring of intracranial pressure and assay of blood barbiturate levels. Global results indicated a mortality of 55.3% and reintegration of 34.2% of the patients. Results as a function of the different parameters of surveillance are discussed.

Adult↗
PubMedDate not supplied

[Characteristics of families of women with restricting anorexia nervosa compared with families of normal probands].

This study compares families of women with restricting anorexia nervosa with families of women without any psychiatric history on the following variables: parents' eating problems (Eating Attitudes Test: EAT-26) and psychopathology (Symptom Checklist-90-R: SCL-90-R); family members' perceptions of the parent-daughter relationship (Parental Bonding Instrument: PBI) and the family's overall functioning (Self-Report Family Inventory: SFI). Twenty-eight young women suffering from restricting anorexia nervosa, 27 non-clinical women and their respective parents, completed these questionnaires and also participated in a semi-structured individual interview. Our results demonstrated that parents in the two groups had similar eating attitudes and behaviors. However, parents of women with anorexia nervosa reported more problems with alcohol consumption than non-clinical parents. There were no differences between the two groups on the measure of family functioning (SFI), all scores in the families of anorectics being within normal limits. All the daughters, however, reported less family cohesion and more family conflict than did their parents. On the PBI, all the daughters reported receiving more care from their mothers than their fathers; the anorectic women reported experiencing more maternal control, intrusiveness and overprotection. The relationship between each family member's perception of family functioning and the parent-daughter relationship was examined. Anorectic daughters associate the emotional health of their family with the care received from both parents, whereas control women associate this variable with their father's attitudes and behaviors. However, fathers from both groups do not consider their own care or protection as having contributed to the health of the family.

Adolescent↗