A Milestone in the Treatment of Ataxias: Approval of Omaveloxolone for Friedreich Ataxia.

The exciting news about the US FDA approval of omaveloxolone as the first-ever drug to be approved for an inherited ataxia is welcome news for patients and families that deal with this devastating disease as well as for health care providers and investigators with an interest in this and other rare diseases. This event is the culmination of long and fruitful collaboration between patients, their families, clinicians, laboratory researchers, patient advocacy organizations, industry, and regulatory agencies. The process has generated intense discussion about outcome measures, biomarkers, trial design, and the nature of approval process for such diseases. It also has brought hope and enthusiasm for increasingly better therapies for genetic diseases in general.

Activation of the cannabinoid CB1 receptor may involve a W6 48/F3 36 rotamer toggle switch.

The cannabinoid CB1 receptor, a member of the Rhodopsin (Rho) family of G protein coupled receptors (GPCRs), exhibits high levels of constitutive activity. In contrast, Rho exhibits an exquisite lack of constitutive activity. In Rho, W6.48(265) on transmembrane helix 6 (TMH6) is flanked by aromatic residues at positions i-4 (F6.44) and i + 3 (Y6.51), while in CB1 the residues i-4 and i + 3 to W6.48 are leucines (L6.44 and L6.51). Based upon spectroscopic evidence, W6.48 has been proposed to undergo a rotamer switch (chi1 g+ -->trans) upon activation of Rho. In the work reported here, the biased Monte Carlo method, Conformational Memories (CM) was used to test the hypothesis that the high constitutive activity exhibited by CB1 may be due, in part, to the lack of aromatic residues i-4 and i + 3 from W6.48. In this work, the W6.48 rotamer shift (chi1 g+ -->trans) was used as the criterion for activation. Conformational Memories (CM) calculations on WT CB1 TMH6 and L6.44F and L6.51Y mutant TMH6s revealed that an aromatic residue at 6.44 tends to disfavor the W6.48 chi1 g+ -->trans transition and an aromatic residue at 6.51 would require a concomitant movement of the Y6.51 chi1 from trans-->g+ when the W6.48 chi1 undergoes a g+ -->trans shift. In contrast, CM calculations on WT CB1 TMH6 revealed that the presence of leucines at 6.44 and 6.51 provide W6.48 with greater conformational mobility, with a W6.48 transchi1 preferred. Conformational Memories calculations also revealed that the W6.48 chi1 g+ -->trans transition in WT CB1 TMH6 is correlated with the degree of kinking in TMH6. The average proline kink angles for TMH6 were higher for helices with a W6.48 g+ chi1 than for those with a W6.48 transchi1. These results are consistent with experimental evidence that TMH6 straightens during activation. Transmembrane helix (TMH) bundle models of the inactive (R) and active (R*) states of CB1 were then probed for interactions that may constrain W6.48 in the inactive state of CB1. These studies revealed that F3.36 (transchi1) helps to constrain W6.48 in a g+ chi1 in the inactive (R) state of CB1. In the R* state, these studies suggest that F3.36 must assume a g+ chi1 in order to allow W6.48 to shift to a transchi1. These results suggest that the W6.48/F3.36 interaction may act as the 'toggle switch' for CB1 activation, with W6.48 chi1 g+/F3.36 chi1 trans representing the inactive (R) and W6.48 chi1 trans/F3.36 chi1 g+ representing the active (R*) state of CB1.

Prior childhood sexual abuse in mothers of sexually abused children.

OBJECTIVE: To see if mothers who were sexually abused in their own childhood are at increased risk of their children being sexually abused and to see if prior sexual abuse in mothers affects their parenting abilities. METHOD: Sixty-seven mothers whose children had been sexually abused by others and 65 control mothers were asked about sexual abuse in their own childhood. The sexually abused children of mothers who had been sexually abused in their own childhood were compared with the sexually abused children of mothers who had not suffered child sexual abuse as children. Comparisons were made on self-esteem, depression and behavior in the children. RESULTS: Thirty-four percent of mothers of sexually abused children gave a history of sexual abuse in their own childhoods, compared with 12% of control mothers. Assessment of the sexually abused children for self-esteem, depression and behavior at the time of diagnosis, after 18 months and after 5 years showed no difference in any of these measures at any of the three time intervals between those whose mothers had suffered child sexual abuse and those whose mothers had not been abused. CONCLUSION: In this study, sexual abuse in a mother's own childhood was related to an increased risk of sexual abuse occurring in the next generation, although prior maternal sexual abuse did not effect outcome in children who were sexually abused.

Acute and chronic effects of bilateral lung transplantation without cardiopulmonary bypass on the first transplanted lung.

BACKGROUND: Bilateral lung transplantation (BLT) without cardiopulmonary bypass (CPB) may exacerbate reperfusion injury to the initially engrafted lung because of increases in pulmonary flow during implantation of the second graft. METHODS: In a retrospective review of 23 BLT patients, we hypothesized that BLT without CPB injures the first transplanted lung measured by acute and late graft dysfunction compared to the second transplanted lung. Of the 23 BLT, 19 underwent transplantation without CPB while 4 patients were placed on CPB secondary to hemodynamic instability. RESULTS: Acute graft function was assessed by radiographic scoring of lung quadrants (blinded radiologist; 0 = no infiltrate; 1 = infiltrate; maximum = 2 per lung) and by arterial/alveolar oxygen tension ratios (PaO2/ FiO2) ratios. Late graft function was evaluated by quantitative perfusion scan. Lung perfusion was graded as abnormal if less than 50% on the right or less than 45% on the left (Fisher's exact). Radiographic scores were not different between first and second implanted lungs at 1 and 24 hours, PaO2/FiO2 ratios at 1 and 24 hours were 273+/-26 and 312+/-23, respectively, and perfusion scans at 3 and 12 months revealed normal differential blood flow. CONCLUSIONS: These findings suggest no acute or chronic differences occur between the first or second transplanted lung completed without CPB.

Self esteem, depression, behaviour and family functioning in sexually abused children.

Eighty-four sexually abused children and their families, were compared with controls to look at short-term effects of sexual abuse. The abuse group had more marital breakdown, unemployment, communication problems within the family and poor marital mental health. The abused children had more depression, low self-esteem and behaviour disorder. There was no relationship between intrafamilial abuse and depression, self-esteem or behaviour disorder. More severe abuse was related to low self-esteem and children's negative perceptions of their mothers. In planning treatment the child's relationship to the perpetrator may need less emphasis, with more on self-esteem, depression, family functioning and the child's perceptions of the family.

The criminal justice system and the sexually abused child. Help or hindrance?

OBJECTIVE: To assess the progress of 59 sexually abused children in the criminal justice system to see whether they testified, whether there were any effects on their self-esteem or behaviour, whether it resulted in depression and what their parents' perceptions of the process were. DESIGN: A prospective study of sexually abused children, with data from interviews with the parents and psychological testing of the children. RESULTS: Thirty-three cases were committed for trial or sentencing, resulting in 20 convictions. Twenty-two children testified at the committal hearing and eight at trials. Although 55% of parents expressed dissatisfaction with the legal system, thinking it was stressful to their children, a comparison of children who did not testify with those who did showed no significant differences on indices of depression, self-esteem or behaviour. As most children were involved in court-preparation programs and most mothers were supportive of their children, these may have been ameliorating factors. CONCLUSIONS: Even though the initial stressful effects of children appearing in court appear to be transient, there should be increased use of screens, closed-circuit television and preparation-for-court programs to make court appearances less intimidating.

Stability and change in outcomes for sexually abused children.

OBJECTIVE: To evaluate sexually abused children and their families at intake and 18 months later, in comparison with a control group. METHODS: Eighty-four sexually abused children aged 5 to 15 years were assessed at intake, with 64 being able to be reassessed at 18 months, the assessment using measures of self-esteem relevant to their age; the Children's Depression Inventory, and the Achenbach Child Behavior Checklist. Parents were assessed with the McMaster Family Assessment Device and the General Health Questionnaire. Control children and families were similarly assessed. Additional measures at follow-up were a structured interview with the parents, the Indices of Coping Responses, and the Newcastle Child and Family Life Events Schedule. Therapists were contacted to obtain information on type and duration of therapy. RESULTS: While the control children's self-esteem, depression, and behavior scores showed little change over time, the abused children's scores were more likely to move toward the normal range although 56% remained in the dysfunctional range for self-esteem, 48% for behavior, and 35% for depression. Improvement in child behavior was related to improvement in family function. While there was no direct relationship between child outcome and the relationship of the abuser to the child, family dysfunction, which was related to child outcome, did correlate with the closeness of the abuser to the child. Sixty-five percent of abused children had received therapy for an average of 9 months. No relationship was found between therapy and outcome. CONCLUSIONS: The major variable relating to improvement in sexually abused children appears to be adequacy of family functioning. There is a need for increased emphasis on the evaluation of treatment.

Who participates in child sexual abuse research?

This paper stems from a prospective case control study of the effects of child sexual abuse and explores issues of sampling bias resulting from non-participation in research. Despite similarities in family demographics and in the level of abuse experienced, differences between the study participants and non-participants emerged. The more dysfunctional families were less likely to participate, the research was not a passive experience for the families and finally, non-participants were offered less therapy following clinical assessment. The implications of these differences for the main prospective study will be explored.

Protein, fiber, and mineral nutrition of growing dairy goats.

Seven yearling Alpine does were in a series of balance trials to determine apparent utilization of fiber, protein, and minerals. The 34 kg does consumed 2.2% body weight of a hay-concentrate ration that was 18.8% crude protein, 40.9% neutral detergent fiber, 24.7% acid detergent fiber, 1.18% calcium, .67% phosphorus, .39% magnesium, .98% potassium, and .48% sodium. Digestion coefficients were 59.5, 68.5, 42.3, 70.6, and 29.3 for dry matter, crude protein, neutral detergent fiber, hemicellulose, and acid detergent fiber. Retention (g/day) was: 2.6, 1.3, 2.1, 1.8, and 1.1 for calcium, phosphorus, potassium, sodium, and magnesium. Nitrogen intake was related in a positive linear fashion to fecal nitrogen, urinary nitrogen, and absorbed nitrogen. Apparent absorption rates were 2.7, 1.4, 1.3, 5.1, and 3.2 g per doe per day for calcium, phosphorus, magnesium, potassium, and sodium. Mineral retentions as percent of grams apparently absorbed were 96.2, 88.2, 80.9, 37.7, and 56.0.

Divalent cation dependent resistance in E. coli LMR-26 to the broad spectrum antimicrobial agent irgasan.

Strains of E. coli found in nature are commonly sensitive to irgasan at concentrations of 1-3 ppm. However, E. coli LMR-26 has been shown to be resistant in media up to a maximum of 35 ppm irgasan. The presence of a divalent cation (Mg++ or Ca++) for this resistance is required in the medium. Resistance to similar concentrations of hexachlorophene with Mg++ was also observed with E. coli LMR-26. Comparative analysis of total envelope proteins gel electrophoresis showed no significant differences between an irgasan-sensitive wild strain and the resistant organism. However, gas liquid chromatography did indicate significant differences in the envelope fatty acids of the two organisms. Electron microscopy revealed major morphological modifications in the resistant organism subjected to an irgasan stress. A possible mechanism of resistance is discussed.

Effect of irgasan on bacterial growth and its adsorption into the cell wall.

Isolated cell walls and whole cells of E. coli, S. aureus and P. aeruginosa were shown to adsorb irgasan, with P. aeruginosa adsorbing the greatest amount of irgasan per microgram of cell wall and whole cell tested. The drug uptake displayed by both cell walls and whole cells appears to be by diffusion. Although P. aeruginosa revealed the highest affinity for the bisphenol of the three organisms tested, it was most resistant to its antibacterial action. These results indicated that the lipid content of the cell wall may be responsible for the degree of adsorption and resistance since P. aeruginosa showed the most adsorption, resistance and the highest cell wall lipid content of the three micro-organisms tested.

Irgasan-induced pigmentation in Serratia marcescens and Pseudomonas aeruginosa.

Two irgasan-resistant micro-organisms (P. aeruginosa and S. marcescens) were used to study the effects of various antibiotic and chemotherapeutic agents on pigment production. These agents included streptomycin, thallium acetate, polymyxin B, hexachlorophene, irgasan, prodigiosin and DMSO (dimethyl sulphoxide). Only irgasan, compared to other drugs and membrane-active agents showed the unique property of inducing pigmentation in both P. aeruginosa and S. marcescens, i.e. prodigiosin in S. marcescens and pyocyanin in P. aeruginosa.

A qualitative and quantitative study of the fatty acid composition of selected micro-organisms.

Fatty acid content was found to be an important parameter in the identification and numerical taxonomy of many micro-organisms. Isolates of the same species and genus as well as members of many well defined groups, such as the Enterobacteriaceae, were included in the study. A direct methylation procedure of the bacteria was found to be accurate, efficient and rapid. Fatty acids were found to be reliable indicators of micro-organisms in group, generic, specific and strain identification. Other biochemical tests were especially valuable when used in conjunction with fatty acid profiles in identification and classification of the bacteria studied.

Toxigenic studies with the antibiotic pigments from Serratia marcescens.

Prodigiosin, obtained from the bacterium, Serratia marcescens, was extracted in five organic solvents, petroleum ether, chloroform, acetone, ethanol, and methanol, and the fractions were labeled PE-1, C-2, A-3, E-4, and M-5 respectively. The effects of prodigiosin and its fractions on embryogenesis showed the whole pigment and C-2 fraction to be highly toxigenic while other fractions demonstrated toxicities approaching LD50 values of 26-30 mug/egg when dissolved in 100% dimethyl sulfoxide. The E-4 fraction in DMSO was least toxic. Ninety-five percent ethanol proved to be highly toxic at a dose level of 0.1 ml/egg indicating that it was an unsuitable solvent for studies of this nature. Disc-agar diffusion sensitivity studies were performed against E. coli, E. aerogenes, S. aureus, B. subtilis, and P. aeruginosa with prodigiosin and fractions dissolved in 100% DMSO. The solvent was found to have no diffusible bacteriostatic activity in vitro. However, prodigiosin and the ethanol (E-4) and methanol (M-5) fractions produced inhibition zones with every organism tested. Data presented below indicate that prodigiosin extracts have toxigenic effects on chick embryos and inhibit the growth of several species of bacteria.

Chromatographic separation of the pigment fractions from a Serratia marcescens strain.

A procedure was developed for the separation of pigment fractions in a wild-type Serratia marcescens strain. Separation was achieved by column chromatography and elution with several organic solvents. At least six pigment fractions were obtained from the alumina columns by this technique, whereas only four fractions had been reported previously. Spectral and elemental analyses indicate that, in S. marcescens, prodigiosin is a complex of six fractions, differing in absorption spectra while retaining the general characteristics of the whole pigment.