Examining the bidirectional relationship between posttraumatic stress disorder symptom clusters and PAP adherence

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a common sleep disturbance in individuals with posttraumatic stress disorder (PTSD), with an emerging literature showing that treating OSA with positive airway pressure (PAP) therapy has a moderate effect on decreasing PTSD severity. Unfortunately, PAP adherence among individuals with PTSD is low. Our study examined how baseline PTSD cluster subscores predict 6-month PAP adherence and how PAP adherence predicts change in PTSD cluster subscores over time.

METHODS

We examined PTSD and PAP adherence in 41 veterans with PTSD newly diagnosed with OSA over 6 months of PAP use (mean age = 50.27 years; 73.7% White; 13.6% female). The Posttraumatic Stress Disorder Checklist-Specific (PCL-S) was used to examine PTSD and subscales (re-experiencing, avoidance, and hyperarousal). We used longitudinal analyses to examine PTSD subscores on PAP adherence and PAP adherence predicting changes in PTSD subscores at 6-month follow-up.

RESULTS

Among veterans with PTSD, higher levels of re-experiencing and hyperarousal, but not avoidance, predicted lower PAP use. Overall, the high-adherent group showed a 14.36-point decrease on the PCL-S, while the low-adherent group averaged just a 3.66-point decrease. More days of PAP use were associated with greater improvement in hyperarousal and avoidance subscores but not re-experiencing.

CONCLUSIONS

Our findings reaffirm the importance of PAP use among patients with comorbid PTSD and sleep apnea, as well as the difficulty in achieving adherent PAP use in this population. Directly addressing heightened re-experiencing and hyperarousal in PTSD may increase PAP adherence among veterans with PTSD and requires future research.

CITATION

Colvonen PJ, Goldstein LA, Sarmiento KF. Examining the bidirectional relationship between posttraumatic stress disorder symptom clusters and PAP adherence. J Clin Sleep Med. 2023;19(5):857-863.

Lifetime history of interpersonal partner violence is associated with insomnia among midlife women veterans

OBJECTIVE

Over a third of women in the United States report a lifetime history of intimate partner violence. Although a recent review found that intimate partner violence is related to poor subjective sleep, the majority of studies involved reproductive-aged women and used suboptimal measures of interpersonal violence and/or insomnia. We examined the relationship between lifetime intimate partner violence and current clinical insomnia in a cross-sectional sample of midlife women veterans.

METHODS

Cross-sectional data were drawn from the Midlife Women Veterans Health Survey. Women Veterans (N = 232) aged 45 to 64 years enrolled in Department of Veterans Affairs health care in Northern California completed an adapted version of the Extended-Hurt, Insult, Threaten, Scream to assess lifetime history of intimate partner violence (screening threshold score and any physical, sexual, and psychological intimate partner violence) and the Insomnia Severity Index to assess current insomnia.

RESULTS

In multivariable analyses, lifetime history of intimate partner violence was associated with twofold to fourfold odds of current clinical insomnia, including overall intimate partner violence (odds ratio, 3.24; 95% confidence interval, 1.57-6.69), physical intimate partner violence (odds ratio, 2.01; 95% confidence interval, 1.09-3.70), psychological intimate partner violence (odds ratio, 3.98; 95% confidence interval, 2.06-7.71), and sexual intimate partner violence (odds ratio, 2.09; 95% confidence interval, 1.08-4.07).

CONCLUSIONS

Lifetime history of intimate partner violence is common and may be associated with clinical insomnia during midlife. Findings highlight the importance of screening midlife women for intimate partner violence and recognizing the potential role of this traumatic exposure on women's health.

Barriers to positive airway pressure adherence among veterans with sleep apnea: a mixed methods study

Rates of adherence to positive airway pressure (PAP) for sleep apnea are suboptimal. Though previous studies have identified individual factors associated with PAP nonadherence, few projects have investigated a wide range of possible barriers directly from the patient perspective. We examined the range of factors that patients identify as barriers to optimal use of PAP as well as the solutions most commonly offered by providers. We employed a mixed methods design including semistructured interviews and medical record review at a US Department of Veterans Affairs Medical Center. Thirty patients identified as nonadherent to PAP participated. Patients were asked to report on current sleep problems, reasons for nonadherence, and solutions proposed by providers. Chart review was used to identify untreated apnea severity, Epworth Sleepiness Scale score, therapy hours, and residual apnea severity. Patients described physical and psychological barriers to adherent use at approximately equal rates: Mask leaks and dry throat/nose were common physical barriers, and anxiety/claustrophobia and worsening insomnia were common psychological barriers. Untreated apnea severity, residual apnea severity, and daytime sleepiness were not associated with therapy hours. Solutions offered by providers most frequently addressed physical barriers, and solutions to psychological barriers were rarely proposed. The most common solution offered by providers was trying different masks. We recommend individualized assessment of each patient's barriers to use as well as increased involvement of behavioral health providers in sleep medicine clinics.

Brief behavioral treatment for insomnia improves psychosocial functioning in veterans: results from a randomized controlled trial

STUDY OBJECTIVES

Our goal was to compare brief behavioral treatment for insomnia (BBTI) to a progressive muscle relaxation training (PMRT) control condition among veterans with insomnia, examining psychosocial functioning as a primary outcome and sleep-related outcomes, mood, cognition, and pain as secondary outcomes.

METHODS

Veterans were randomly assigned to either BBTI or PMRT (N = 91; 24-74 years; M = 49 years). BBTI consisted of two in-person (60-min and 30-min sessions) and two telephone sessions (20-min each), and the PMRT control condition was matched to BBTI for session duration and type. Veterans were assessed through clinical interview at baseline and self-report measures at pre-, mid-, and posttreatment, as well as 6-month follow-up for the BBTI condition to assess sustained response. Measures also included continuous sleep monitoring with sleep diary.

RESULTS

Intent-to-treat analyses demonstrated that individuals who completed BBTI versus PMRT reported greater improvements in work, home, social and cognitive functioning, insomnia symptom severity, mood, and energy. Improvements in psychosocial functioning, insomnia symptoms, and mood were maintained 6-months following BBTI treatment completion.

CONCLUSIONS

Veterans who received BBTI improved and maintained gains in psychosocial functioning, insomnia, and mood. BBTI is a treatment that can be implemented in primary care, mental health, or integrated care settings and provide symptom relief and improved functioning among those with insomnia, one of the most commonly reported mental health problems among veterans.

CLINICAL TRIAL REGISTRATION

NCT02571452.

Recent Advancements in Treating Sleep Disorders in Co-Occurring PTSD

PURPOSE OF REVIEW

Comorbidity of posttraumatic stress disorder (PTSD) and insomnia, nightmares, and obstructive sleep apnea (OSA) is high. We review recent research on psychotherapeutic and pharmacological interventions for sleep disorders in PTSD.

RECENT FINDINGS

PTSD treatments decrease PTSD severity and nightmare frequency, but do not resolve OSA or insomnia. Research on whether insomnia hinders PTSD treatment shows mixed results; untreated OSA does interfere with PTSD treatment. Cognitive behavioral therapy for insomnia is the recommended treatment for insomnia; however, optimal ordering with PTSD treatment is unclear. PTSD treatment may be most useful for PTSD-related nightmares. CPAP therapy is recommended for OSA but adherence can be low. Targeted treatment of sleep disorders in the context of PTSD offers a unique and underutilized opportunity to advance clinical care and research. Research is needed to create screening protocols, determine optimal order of treatment, and elucidate mechanisms between sleep and PTSD treatments.

Military sexual trauma is associated with eating disorders, while combat exposure is not

OBJECTIVE

There are strong associations among trauma and eating disorders. However, while trauma and eating disorders are more common among veterans than other populations, there is little information on how military-specific stressors affect eating disorder risk. This study's objective was to determine whether military sexual trauma and combat exposure were independent predictors of eating disorders among women veterans, a high-risk group.

METHOD

Participants were women age 18-70, using VA medical center services, without psychotic disorders or suicidal ideation (N = 407). We estimated a cross-sectional logistic regression model to predict eating disorders (anorexia, bulimia, binge eating disorder) as a function of military sexual trauma and combat exposure, adjusting for demographic variables.

RESULTS

Sixty-six percent of participants reported military sexual trauma, 32% reported combat exposure, and 15% met eating disorder criteria. Mean age was 49 years (SD = 13); 40% were veterans of color. Women reporting military sexual trauma had twice the odds of an eating disorder compared to women who did not (odds ratio [OR]: 2.03; 95% CI [1.03-3.98]). Combat exposure was not associated with eating disorders. Asian race (OR: 3.36; 95% CI [1.26-8.97]) and age (OR: 1.03; 95% CI [1.01-1.06]) were associated with eating disorders.

CONCLUSIONS

The high rates of military sexual trauma and eating disorders highlight a need for continued work. Results suggest that it may be useful to focus on women reporting military sexual trauma when implementing eating disorder screening and treatment programs. Given associations among trauma, eating disorders, obesity, and mortality, such efforts could greatly improve veteran health. (PsycINFO Database Record

Veterans Group Exercise: A randomized pilot trial of an Integrative Exercise program for veterans with posttraumatic stress

BACKGROUND

Posttraumatic stress disorder (PTSD) is prevalent among military veterans and is associated with significant negative health outcomes. However, stigma and other barriers to care prevent many veterans from pursuing traditional mental health treatment. We developed a group-based Integrative Exercise (IE) program combining aerobic and resistance exercise, which is familiar to veterans, with mindfulness-based practices suited to veterans with PTSD. This study aimed to evaluate the effects of IE on PTSD symptom severity and quality of life, as well as assess the feasibility and acceptability of IE.

METHODS

Veterans (N = 47) were randomized to either IE or waitlist control (WL). Veterans in IE were asked to attend three 1-h group exercise sessions for 12 weeks.

RESULTS

Compared with WL, veterans randomized to IE demonstrated a greater reduction in PTSD symptom severity (d = -.90), a greater improvement in psychological quality of life (d = .53) and a smaller relative improvement in physical quality of life (d = .30) Veterans' ratings of IE indicated high feasibility and acceptability.

LIMITATIONS

The sample was relatively small and recruited from one site. The comparison condition was an inactive control.

CONCLUSIONS

This initial study suggests that IE is an innovative approach to treating veterans with symptoms of PTSD that reduces symptoms of posttraumatic stress and improves psychological quality of life. This approach to recovery may expand the reach of PTSD treatment into non-traditional settings and to veterans who may prefer a familiar activity, such as exercise, over medication or psychotherapy.

Impact of military trauma exposures on posttraumatic stress and depression in female veterans

Previous research has demonstrated the deleterious effects of traumatic military experiences on symptoms of posttraumatic stress disorder (PTSD) and depression in female veterans. However, more research is needed to identify the unique predictors of distressing psychological symptoms when both combat-related and sexual trauma are considered, particularly as women's combat exposure in the military increases. Female veterans who had attended at least one appointment at a large Veterans Health Administration medical center were invited to complete questionnaires about traumatic military exposures and psychiatric symptoms. A total of 403 veterans responded, with 383 respondents' data used in analyses. Multiple regression analyses were conducted with trauma exposure items entered simultaneously to determine their association with symptoms of (1) PTSD and (2) depression. Sexual assault had the strongest relationship with both posttraumatic and depressive symptoms. Sexual assault, sexual harassment, feeling in danger of being killed, and seeing others killed/injured were associated with symptoms of PTSD, but only sexual assault and sexual harassment were associated with symptoms of depression, even when accounting for several aspects of combat exposure. Improving assessment for trauma exposure and developing treatments personalized to type of trauma experienced are important clinical research priorities as female service members' roles in the military expand.

Global epidemiology of amyotrophic lateral sclerosis: a systematic review of the published literature

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is relatively rare, yet the economic and social burden is substantial. Having accurate incidence and prevalence estimates would facilitate efficient allocation of healthcare resources.

OBJECTIVE

To provide a comprehensive and critical review of the epidemiological literature on ALS.

METHODS

MEDLINE and EMBASE (1995-2011) databases of population-based studies on ALS incidence and prevalence reporting quantitative data were analyzed. Data extracted included study location and time, design and data sources, case ascertainment methods and incidence and/or prevalence rates. Medians and interquartile ranges (IQRs) were calculated, and ALS case estimates were derived using 2010 population estimates.

RESULTS

In all, 37 articles met the inclusion criteria. In Europe, the median incidence rate (/100,000 population) was 2.08 (IQR 1.47-2.43), corresponding to an estimated 15,355 (10,852-17,938) cases. Median prevalence (/100,000 population) was 5.40 (IQR 4.06-7.89), or 39,863 (29,971-58,244) prevalent cases.

CONCLUSIONS

Disparity in rates among ALS incidence and prevalence studies may be due to differences in study design or true variations in population demographics such as age and geography, including environmental factors and genetic predisposition. Additional large-scale studies that use standardized case ascertainment methods are needed to more accurately assess the true global burden of ALS.

Outcome assessment via handheld computer in community mental health: consumer satisfaction and reliability

Computerized administration of mental health-related questionnaires has become relatively common, but little research has explored this mode of assessment in "real-world" settings. In the current study, 200 consumers at a community mental health center completed the BASIS-24 via handheld computer as well as paper and pen. Scores on the computerized BASIS-24 were compared with scores on the paper BASIS-24. Consumers also completed a questionnaire which assessed their level of satisfaction with the computerized BASIS-24. Results indicated that the BASIS-24 administered via handheld computer was highly correlated with pen and paper administration of the measure and was generally acceptable to consumers. Administration of the BASIS-24 via handheld computer may allow for efficient and sustainable outcomes assessment, adaptable research infrastructure, and maximization of clinical impact in community mental health agencies.

Developing research and recruitment while fostering stakeholder engagement in a National Institutes of Mental Health-funded Interventions and Practice Research Infrastructure Programs grant for depression

BACKGROUND

In the context of a National Institutes of Mental Health-funded Interventions and Practice Research Infrastructure Programs (IP-RISP) grant for the treatment of depression, a partnership was developed between a community mental health organization and a team of researchers.

OBJECTIVES

This paper describes the collaborative process, key challenges, and strategies employed to meet the goals of the first phase of the grant, which included development of a working and sustainable partnership and building capacity for recruitment and research.

METHODS

This paper was developed through the use of qualitative interviews and discussion with a variety of IP-RISP partners.

LESSONS LEARNED

Communication with multiple stakeholders through varied channels, feedback from stakeholders on research procedures, and employing a research liaison at the clinic have been key strategies in the first phase of the grant.

CONCLUSION

The strategies we employed allowed multiple stakeholders to contribute to the larger mission of the IP-RISP and helped to establish an ongoing research program within the mental health organization.

Unique and common mechanisms of change across cognitive and dynamic psychotherapies

The goal of this article was to examine theoretically important mechanisms of change in psychotherapy outcome across different types of treatment. Specifically, the role of gains in self-understanding, acquisition of compensatory skills, and improvements in views of the self were examined. A pooled study database collected at the University of Pennsylvania Center for Psychotherapy Research, which includes studies conducted from 1995 to 2002 evaluating the efficacy of cognitive and psychodynamic therapies for a variety of disorders, was used. Patient samples included major depressive disorder, generalized anxiety disorder, panic disorder, borderline personality disorder, and adolescent anxiety disorders. A common assessment battery of mechanism and outcome measures was given at treatment intake, termination, and 6-month follow-up for all 184 patients. Improvements in self-understanding, compensatory skills, and views of the self were all associated with symptom change across the diverse psychotherapies. Changes in self-understanding and compensatory skills across treatment were predictive of follow-up symptom course. Changes in self-understanding demonstrated specificity of change to dynamic psychotherapy.

Differential involvement of Bax and Bak in TRAIL-mediated apoptosis of leukemic T cells

TRAIL-induced apoptosis has been considered a promising therapeutic approach for tumors that are resistant to chemotherapy, which is usually mediated via mitochondrial apoptotic cascades. Recent studies have shown that in certain cancer cells, TRAIL-mediated apoptosis is also dependent on mitochondrial involvement, suggesting that similar mechanisms of resistance to chemotherapy might be implicated in the resistance of tumor cells to TRAIL. We have used TRAIL-resistant leukemic cells that are deficient in both Bax and Bak to determine the roles of these Bcl-2 members in TRAIL-mediated apoptosis. Exposure of these cells to TRAIL did not have an impact on cell viability, although it induced the processing of caspase-3 to its active p20 subunit. The activity of the p20 caspase-3 appeared to be inhibited as no autoprocessing of this p20 subunit or cleavage of known caspase-3 substrates were detected. Also, in the absence of Bax and Bak, no release of mitochondrial apoptogenic proteins was observed following TRAIL treatment. Adenoviral transduction of the Bax, but not the Bak gene, to the Bax/Bak-deficient leukemic cells rendered them TRAIL-sensitive as assessed by enhanced apoptotic death and caspase-3 processing. These findings demonstrate preferential utilization of Bax over Bak in leukemic cell response to specific apoptotic stimulation.

Resistance to granzyme B-mediated cytochrome c release in Bak-deficient cells

Granzyme B (GrB), a serine protease with substrate specificity similar to the caspase family, is a major component of granule-mediated cytotoxicity of T lymphocytes. Although GrB can directly activate caspases, it induces apoptosis predominantly via Bid cleavage, mitochondrial outer membrane permeabilization, and cytochrome c release. To study the molecular regulators for GrB-mediated mitochondrial apoptotic events, we used a CTL-free cytotoxicity system, wherein target cells are treated with purified GrB and replication-deficient adenovirus (Ad). We report here that the Bcl-2 proapoptotic family member, Bak, plays a dominant role in GrB-mediated mitochondrial apoptotic events. A variant of Jurkat cells, deficient in Bak expression, was resistant to GrB/Ad-mediated apoptosis, as determined by lack of membranous phosphatidylserine exposure, lack of DNA breaks, lack of mitochondrial outer membrane permeabilization, and unchanged expression of inner mitochondrial membrane cardiolipin. The resistance of Bak-deficient cells to GrB/Ad cytotoxicity was reversed by transduction of the Bak gene into these cells. The requirement for both Bid and Bak, was further demonstrated in a cell-free system using purified mitochondria and S-100 cytosol. Purified mitochondria from Bid knockout mice, but not from Bax knockout mice, failed to release cytochrome c in response to autologous S-100 and GrB. Also, Bak-deficient mitochondria did not release cytochrome c in response to GrB-treated cytosol unless recombinant Bak protein was added. These results are the first to report a role for Bak in GrB-mediated mitochondrial apoptosis. This study demonstrates that GrB-cleaved Bid, which differs in size and site of cleavage from caspase-8-cleaved Bid, utilizes Bak for cytochrome c release, and therefore, suggests that deficiency in Bak may serve as a mechanism of immune evasion for tumor or viral infected cells.

A role for mitochondrial Bak in apoptotic response to anticancer drugs

In the present study a clonal Jurkat cell line deficient in expression of Bak was used to analyze the role of Bak in cytochrome c release from mitochondria. The Bak-deficient T leukemic cells were resistant to apoptosis induced by UV, staurosporin, VP-16, bleomycin, or cisplatin. In contrast to wild type Jurkat cells, these Bak-deficient cells did not respond to UV or treatment with these anticancer drugs by membranous phosphatidylserine exposure, DNA breaks, activation of caspases, or release of mitochondrial cytochrome c. The block in the apoptotic cascade was in the mitochondrial mechanism for cytochrome c release because purified mitochondria from Bak-deficient cells failed to release cytochrome c or apoptosis-inducing factor in response to recombinant Bax or truncated Bid. The resistance of Bak-deficient cells to VP-16 was reversed by transduction of the Bak gene into these cells. Also, the cytochrome c releasing capability of the Bak-deficient mitochondria was restored by insertion of recombinant Bak protein into purified mitochondria. Following mitochondrial localization, low dose recombinant Bak restored the mitochondrial release of cytochrome c in response to Bax; at increased doses it induced cytochrome c release itself. The function of Bak is independent of Bid and Bax because recombinant Bak induced cytochrome c release from mitochondria purified from Bax(-/-), Bid(-/-), or Bid(-/-) Bax(-/-) mice. Together, our findings suggest that Bak plays a key role in the apoptotic machinery of cytochrome c release and thus in the chemoresistance of human T leukemic cells.

Apoptosis-resistant mitochondria in T cells selected for resistance to Fas signaling

Jurkat leukemic T cells are highly sensitive to the extrinsic pathways of apoptosis induced via the death receptor Fas or tumor necrosis factor-related apoptosis-inducing ligand as well as to the intrinsic/mitochondrial pathways of death induced by VP-16 or staurosporin. We report here that clonal Jurkat cell lines selected for resistance to Fas-induced apoptosis were cross-resistant to VP-16 or staurosporin. Each of the apoptotic pathways was blocked at an apical phase, where common regulators of apoptosis have not yet been defined. The Fas pathway was blocked at the level of caspase-8, whereas the intrinsic pathway was blocked at the mitochondria. No processing or activity of caspases was detected in resistant cells in response to either Fas-cross-linking or VP-16 treatment. Also, no apoptosis-associated alterations in the mitochondrial inner membrane, outer membrane, or matrix were detected in resistant Jurkat cells treated with VP-16. Thus, no changes in permeability transition, loss in inner membrane cardiolipin, generation of reactive oxygen species, or release of cytochrome c were observed in resistant cells treated with VP-16. Further, unlike purified mitochondria from wild type cells, those obtained from resistant cells did not release cytochrome c or apoptosis-inducing factor in response to recombinant Bax or truncated Bid. These results identify a defect in mitochondria ability to release intermembrane proteins in response to Bid or Bax as a mechanism of resistance to chemotherapeuetic drugs. Further, the selection of VP-16-resistant mitochondria via elimination of Fas-susceptible cells may suggest the existence of a shared regulatory component between the extrinsic and intrinsic pathways of apoptosis.

Identification of an alternatively spliced seprase mRNA that encodes a novel intracellular isoform

Seprase is a homodimeric 170-kDa integral membrane gelatinase that is related to the ectoenzyme dipeptidyl peptidase IV. We have identified an alternatively spliced seprase messenger from the human melanoma cell line LOX that encodes a novel truncated isoform, seprase-s. The splice variant mRNA is generated by an out-of-frame deletion of a 1223-base pair exonic region that encodes part of the cytoplasmic tail, transmembrane, and the membrane proximal-central regions of the extracellular domain (Val(5) through Ser(412)) of the seprase 97-kDa subunit (seprase-l). The seprase-s mRNA has an elongated 5' leader (548 nucleotides) that harbors at least two upstream open reading frames that inhibit seprase-s expression from a downstream major open reading frame. Deletion mutagenesis of the wild type splice variant cDNA confirms that initiation of the seprase-s coding sequence begins with an ATG codon that corresponds to Met(522) of seprase-l. The seprase-s open reading frame encodes a 239-amino acid polypeptide with an M(r) approximately 27,000 that precisely overlaps the carboxyl-terminal catalytic region of seprase-l.

Economic costs of motor vehicle crashes involving teenaged drivers in Kentucky, 1994

OBJECTIVES

To analyze data from motor vehicle crashes (MVCs) involving teenaged drivers in Kentucky for 1994, and derive cost estimates of these crashes.

METHODS

Crash data were obtained from the Kentucky Traffic Accident Facts 1994 Report and the Kentucky Accident Reporting System. The National Highway Traffic Safety Administration's Crash-Cost program was used to generate cost estimates for Kentucky data.

RESULTS

Teenaged drivers had significantly higher MVC fatal and non-fatal injury rates than did adult drivers. The deaths rates were 43.6 and 19.0 per 100,000 for teens and adult drivers, respectively. Odds ratios (ORs) were calculated to estimate the relative risk for (1) involvement in an MVC, (2) fatal or incapacitating injury, and (3) fatal injury for teenaged compared with adult drivers. The crude ORs were statistically significant at each age. Cost estimates were calculated on a per person/vehicle basis. A single fatal injury was $642,700. A critical injury was $563,000. In general, unit costs rose with increasing levels of injury severity. For the total number of fatal injuries, costs exceeded $91 million. For non-fatal injuries and property damage only crashes, total costs were $318 million. Overall, the total cost estimate for MVCs involving teenaged drivers was nearly $410 million.

CONCLUSIONS

Strategies aimed to reduce the number of MVCs attributed to teenaged drivers should reduce both the number and costs of crash related deaths and injuries. Graduated driver licensing (GDL) systems are one plausible approach toward achieving this goal. By recently enacting a GDL system in Kentucky, it is anticipated that many lives and dollars will be saved.

Molecular cloning of seprase: a serine integral membrane protease from human melanoma

Seprase is a homodimeric 170 kDa integral membrane gelatinase whose expression correlates with the invasiveness of the human melanoma cell line LOX. Here, we report the molecular cloning of a cDNA that encodes the 97 kDa subunit of seprase. Its deduced amino acid sequence predicts a type II integral membrane protein with a cytoplasmic tail of 6 amino acids, followed by a transmembrane domain of 20 amino acids and an extracellular domain of 734 amino acids. The carboxyl terminus contains a putative catalytic region (approximately 200 amino acids) which is homologous (68% identity) to that of the nonclassical serine protease dipeptidyl peptidase IV (DPPIV). The conserved serine protease motif G-X-S-X-G is present as G-W-S-Y-G. However, sequence analysis of seprase cDNA from LOX and other cell lines strongly suggests that seprase and human fibroblast activation protein alpha (FAP alpha) are products of the same gene. We propose that seprase/FAP alpha and DPPIV represent a new subfamily of serine integral membrane proteases (SIMP).

Identification of the 170-kDa melanoma membrane-bound gelatinase (seprase) as a serine integral membrane protease

The 170-kDa membrane-bound gelatinase, seprase, is a cell surface protease, the expression of which correlates with the invasive phenotype of human melanoma and carcinoma cells. We have isolated seprase from cell membranes and shed vesicles of LOX human melanoma cells. The active enzyme is a dimer of N-glycosylated 97-kDa subunits. Sequence analysis of three internal proteolytic fragments of the 97-kDa polypeptide revealed up to 87.5% identity to the 95-kDa fibroblast activation protein alpha (FAPalpha), the function of which is unknown. Thus, we used reverse transcription-polymerase chain reaction to generate a 2.4-kilobase cDNA from LOX mRNA with FAPalpha primers. COS-7 cells transfected with this cDNA expressed a 170-kDa gelatinase that is recognized by monoclonal antibodies directed against seprase. Sequence analysis also showed similarities to the 110-kDa subunit of dipeptidyl peptidase IV (DPPIV). Like DPPIV, the gelatinase activity of seprase was completely blocked by serine-protease inhibitors, including diisopropyl fluorophosphate. Seprase could be affinity-labeled by [3H]diisopropyl fluorophosphate, but the proteolytically inactive 97-kDa subunit could not, confirming the existence of a serine protease active site on the dimeric form. Proteolytic activity is lost upon dissociation into its 97-kDa subunit following treatment with acid, heat, or cysteine and histidine-modifying agents. We conclude that seprase, FAPalpha, and DPPIV are related serine integral membrane proteases and that seprase is similar to DPPIV, the proteolytic activities of which are dependent upon subunit association.

The neuronal voltage-gated sodium channel, Scn8a, is essential for postnatal maturation of spinal, but not oculomotor, motor units

Mice with a nontargeted transgene insertion at the motor endplate disease (med) locus (med(tg)) contain a deletion of a novel gene encoding a neuronal voltage-gated sodium channel, designated Scn8a. We characterized severe skeletal muscle atrophy beginning by Postnatal Day 10 (P10) and death by P20 in the med(tg) mouse. Denervation was functional, rather than structural, since the Scn8a mutation was not accompanied by retraction of neuromuscular contacts, motoneuron death, or decreased motoneuron soma diameter. Although pathology consistent with denervation was seen in both hindlimb and forelimb musculature, the postnatal maturation of the extraocular muscles was not altered. The onset of paralysis is likely coincident with the time that the Scn8a sodium channel normally assumes a critical role in the initiation and/or propagation of action potentials in spinal motoneurons. By contrast, the lack of consequences for extraocular muscle suggests that the Scn8a voltage-gated sodium channel may be of relatively minor importance for oculomotor motoneurons.

Motoneuron development after deafferentation. I. dorsal rhizotomy does not alter growth in the spinal nucleus of the bulbocavernosus (SNB)

The spinal nucleus of the bulbocavernosus (SNB) and the dorsolateral nucleus (DLN) are sexually dimorphic motor nuclei in the rat lumbar spinal cord. During postnatal development, SNB and DLN motoneurons grow substantially in measures of soma size, dendritic length, and radial dendritic extent. SNB motoneurons exhibit a biphasic pattern of dendritic growth, where there is an initial period of exuberant growth followed by a period of retraction to mature lengths by 7 weeks. In this experiment, we examined whether primary afferent input to the SNB nucleus was necessary for the normal postnatal growth of SNB motoneurons. We partially deafferented the SNB via unilateral dorsal rhizotomy of lumbosacral dorsal roots in male rats at 1 week of age. Using cholera toxin horseradish peroxidase (BHRP) to visualize SNB motoneurons, we examined SNB motoneuron morphology at 4 and 7 weeks of age. SNB motoneurons in rhizotomized males developed normally; measures of dendritic length in rhizotomized males were typically exuberant at 4 weeks of age, and declined significantly to mature lengths by 7 weeks of age. In addition, dorsal rhizotomy did not alter the development of SNB motoneuron soma size or radial dendritic extent. These results are discussed in reference to sensorimotor connections in the SNB, the extent of the deafferentation, and dendrodendritic interactions.

Motoneuron development after deafferentation: II. dorsal rhizotomy does not block estrogen-supported growth in the dorsolateral nucleus (DLN)

The lumbar spinal cord of the rat contains two sexually dimorphic motor nuclei, the spinal nucleus of the bulbocavernosus (SNB) and the dorsolateral nucleus (DLN). Postnatally, SNB and DLN motoneurons grow substantially and reach their adult morphology by 7 weeks of age. The masculinization of SNB and DLN motoneuron dendrites depends upon steroid hormones. After early castration, the growth of SNB and DLN dendrites is markedly attenuated, but testosterone replacement restores this growth. In the SNB, initial dendritic growth is also supported in castrates treated with estrogen. By using castration and hormone replacement techniques, we examined the development of DLN motoneuron morphology in estrogen-treated castrated rats to determine if estrogen also supports the growth of DLN motoneurons. In addition, given that dorsal root ganglia may be a site of estrogen action, we tested the hypothesis that estrogen acts at primary afferents to support DLN dendritic growth. Thus, we attempted to block the potential trophic effect of estrogen by performing unilateral dorsal rhizotomies in estrogen-treated castrates. DLN motoneuron morphology was analyzed at 4 and 7 weeks of age by using cholera toxin horseradish peroxidase (BHRP) histochemistry. As found for SNB motoneurons, estrogen treatment transiently supported development. DLN motoneurons in estrogen-treated castrates developed normally through 4 weeks of age, but by 7 weeks, DLN motoneuron morphology in estrogen-treated castrates was no longer different from that in oil-treated castrates. Moreover, deafferentation via unilateral dorsal rhizotomy did not inhibit estrogen's ability to masculinize the early development of DLN motoneurons. Thus, the trophic effect of estrogen did not appear to act via the dorsal root ganglia to support the early postnatal development of DLN motoneurons.

Differential effects of dihydrotestosterone and estrogen on the development of motoneuron morphology in a sexually dimorphic rat spinal nucleus

The rat lumbar spinal cord contains a sexually dimorphic motor nucleus, the spinal nucleus of the bulbocavernosus (SNB), whose motoneurons innervate perineal muscles involved in copulatory reflexes. Dendritic development of SNB motoneurons is biphasic and androgen dependent. During the first 4 postnatal weeks, SNB dendrites grow exuberantly, and subsequently retract to mature lengths by 7 weeks of age. After early postnatal castration, SNB dendrites fail to grow, and testosterone replacement restores this growth. In other systems, testosterone and its metabolites, dihydrotestosterone and estrogen, are important for somatic and neural sexual differentiation. The purpose of the present study was to examine the effects of castration and dihydrotestosterone or estrogen replacement on the growth of SNB motoneuron somata and dendritic arbors. Male rat pups were castrated on postnatal (P) day 7 and treated daily with either dihydrotestosterone propionate (DHTP; 2 mg) or estradiol benzoate (EB; 100 micrograms) until P28 or P49. By using cholera toxin horseradish peroxidase (BHRP) histochemistry, the soma size, dendritic length, dendritic extent, and arbor area of BHRP-labeled SNB motoneurons were measured and analyzed. Both DHTP and EB treatment supported the initial exuberant growth of SNB dendrites through P28, but EB treatment was ineffective in maintaining mature, adult lengths at P49. The possible sites of hormone action and functional implications of these hormonal treatments are discussed.

Motoneuron morphology in the dorsolateral nucleus of the rat spinal cord: normal development and androgenic regulation

The rat lumbar spinal cord contains two sexually dimorphic motor nuclei, the spinal nucleus of the bulbocavernosus (SNB), and the dorsolateral nucleus (DLN). These motor nuclei innervate anatomically distinct perineal muscles that are involved in functionally distinct copulatory reflexes. The motoneurons in the SNB and DLN have different dendritic morphologies. The dendrites of motoneurons in the medially positioned SNB have a radial, overlapping arrangement, whereas the dendrites of the laterally positioned DLN have a bipolar and strictly unilateral organization. During development, SNB motoneuron dendrites grow exuberantly and then retract to their mature lengths. In this experiment we determined whether the adult difference in SNB and DLN motoneuron morphology was reflected in different patterns of dendritic growth during normal development. Furthermore, the development of both these nuclei is under androgenic control. In the absence of androgens, SNB dendrites fail to grow; testosterone replacement supports normal dendritic growth. Thus, we also examined the development of DLN dendrites for similar evidence of androgenic regulation. By using cholera toxin-horseradish peroxidase (BHRP) to label motoneurons retrogradely, we measured the morphology of DLN motoneurons in normal males, and in castrates treated with testosterone or oil/blank implants at postnatal day (P) 7, P28, P49, and P70. Our results demonstrate that in contrast to the biphasic pattern of dendritic development in the SNB, dendritic growth in the DLN was monotonic; the dendritic length of motoneurons increased more than 500% between P7 and P70. However, as in the SNB, development of DLN motoneuron morphology is androgen-dependent. In castrates treated with oil/blank implants, DLN somal and dendritic growth were greatly attenuated compared to those of normal or testosterone-treated males. Thus, while androgens are clearly necessary for the growth of motoneurons in both the SNB and DLN, their different developmental patterns suggest that other factors must be involved in regulating this growth.

Changes in dendritic morphology of rat spinal motoneurons during development and after unilateral target deletion

During normal development, motoneuron dendrites in the spinal nucleus of the bulbocavernosus (SNB) grow exuberantly to almost twice their adult length and then retract. In this study, we retrogradely labeled SNB motoneurons with cholera toxin B-conjugated horseradish peroxidase (BHRP) to examine the maturation of SNB dendritic arbors in more detail, particularly with regard to its spatial distribution and reorganization. The number and orientation of SNB motoneuron primary processes did not change over the first ten weeks of life. In contrast, total dendritic length, radial extent and arbor area increased significantly through the first four postnatal weeks and declined thereafter. The declines in length and extent were restricted to particular portions of the arbor, specifically the dorsal, ipsi- and contralateral projections. Estimates of the degree of overlap between the dendritic arbors from both sides of the SNB reflected these changes, with overlap initially increasing and then decreasing as the SNB established its adult dendritic morphology. To determine if dendritic interactions facilitated by this arbor overlap might be involved in regulating the normal retraction of SNB dendrites, we reduced SNB motoneuron numbers unilaterally by target muscle removal on the day of birth. Somal size, number and orientation of primary processes developed normally in unilateral muscle-extirpated animals. The dendritic morphology of surviving SNB motoneurons in unilateral muscle extirpated males was altered, with significant increases in dendritic length, extent and arbor area relative to those of normal males. These results indicate that substantial changes in dendritic organization of SNB motoneurons occur in normal development and may be influenced by interactions between dendrites from the two halves of the SNB.

Timing and duration of dihydrotestosterone treatment affect the development of motoneuron number and morphology in a sexually dimorphic rat spinal nucleus

The spinal nucleus of the bulbocavernosus (SNB) is a sexually dimorphic motor nucleus in the rat lumbar spinal cord. SNB motoneurons and their perineal target muscles are present in adult males, but reduced or absent in adult females. This dimorphism is due to the presence of androgens during development. Perinatal treatment of females with testosterone (T), or a combination of dihydrotestosterone (DHT) and estrogen (E+D females) from embryonic (E) day 16 through postnatal (P) day 5, results in a masculine number of SNB motoneurons and the retention of the target muscles. Perinatal treatment with estrogen alone does not masculinize the SNB; prenatal treatment with DHT alone from E17-E22 results in a feminine number of SNB motoneurons and a significantly altered motoneuron morphology and connectivity. To determine if masculinization of the SNB involves the interaction of estrogen and DHT or results from a longer exposure to DHT alone, the number, morphology, and connectivity of SNB motoneurons in females treated with DHT both pre- and post-natally (from E16-P5) were examined. At E22, DHTP (E16-P5) females have SNB motoneuron numbers identical to E+D and normal females, but far fewer than normal males, thus indicating that T is essential for prenatal masculinization. After E22, SNB motoneuron number declines precipitously in normal females but remains stable in DHTP (E16-P5) females and E+D females, which do not differ from normal males at P10. These results demonstrate that DHT can completely masculinize SNB motoneuron number without any synergistic actions with estrogen, and suggest that the development of SNB motoneuron number is strictly an androgen-mediated event. In adulthood, horseradish peroxidase histochemistry reveals that the connectivity, dendritic length, and soma size of SNB motoneurons in DHTP (E16-P5) females are identical to those of normal males but differ significantly from those of DHTP (E17-E22) females. These data suggest that the altered connectivity in DHTP (E17-E22) females is not simply a hormone-specific effect, but the result of a truncated hormone exposure. Thus, DHT can fully masculinize SNB morphology and connectivity if given during the appropriate period of development. It is suggested that while T may be required to masculinize the SNB prenatally, DHT may be involved in masculinizing postnatal aspects of SNB development.

Identification of mRNA that encodes an alternative form of H-CAM(CD44) in lymphoid and nonlymphoid tissues

The cluster of differentiation 44 (CD44), hereafter referred to as H-CAM(CD44), represents a novel class of polymorphic (Mr 80,000-215,000) cell adhesion molecules that are involved in cell-cell and cell-matrix adhesion events in a variety of organ systems. We report the detection of distinct mRNAs, in both hematopoietic and nonhematopoietic human cell lines, that encode H-CAM(CD44) with different cytoplasmic domains. Genomic Southern blot analyses indicate that the exons encoding these two cytoplasmic domains are located on the same approximately 16 kilobase (kb) Eco RI restriction fragment. Restriction endonuclease and Southern blot analyses performed on polymerase chain reaction (PCR) amplification copies of these mRNAs confirm that their sequences correspond with previously reported cDNA sequences. A consensus splice donor site which is conserved in human, baboon, and mouse mRNAs that encode a molecule with an elongated cytoplasmic domain (H-CAM-L) is utilized to generate a distinct but low-abundance mRNA species that encodes H-CAM(CD44) with a truncated cytoplasmic domain of only three amino acids (H-CAM-S). Estimations of the relative abundance of these mRNA species in B-lymphoblastoid cells using the PCR amplification technique exhibit average H-CAM-L/H-CAM-S ratios ranging between 100 and 200. Therefore, H-CAM (CD44)-mediated adhesive events may be regulated through a differential capacity of H-CAM-L and H-CAM-S to interact with the cytoskeleton and to participate in intracellular signaling events.

Hormonal control of neuron number in sexually dimorphic spinal nuclei of the rat: IV. Masculinization of the spinal nucleus of the bulbocavernosus with testosterone metabolites

The spinal nucleus of the bulbocavernosus (SNB) is a sexually dimorphic motor nucleus in the rat lumbar spinal cord. SNB motoneurons and their perineal target muscles are present in adult males but reduced or absent in females. This sexual dimorphism is due to the presence of androgen during development; females treated with testosterone (T) perinatally have a masculine SNB system. To assess whether masculinization of the SNB could involve the conversion of testosterone into its active metabolites, dihydrotestosterone (DHT) and estrogen, we examined the development of the SNB in females treated perinatally with estrogen alone or in combination with dihydrotestosterone. Counts of motoneurons in the developing SNB in all groups showed the typical prenatal increase followed by a differential postnatal decline; the incidence of degenerating cells reflected this decline. Motoneuron numbers and the frequency of degenerating cells in females treated with estrogen (E) alone did not differ from those of normal females, with both groups losing large numbers of motoneurons and having a high incidence of degenerating cells. In contrast, females treated with both estrogen and dihydrotestosterone did not show the female-typical decline in motoneuron number and had a low, masculine incidence of degenerating cells. By postnatal day 10, females treated with estrogen and dihydrotestosterone had a fully masculine SNB motoneuron number, suggesting that dihydrotestosterone alone or in conjunction with estrogen may be involved in the development of the sexually dimorphic SNB system.

Androgen regulation of dendritic growth and retraction in the development of a sexually dimorphic spinal nucleus

The spinal nucleus of the bulbocavernosus (SNB) is a sexually dimorphic group of motoneurons whose development and maintenance are under androgenic control. Exposure to androgens early in development permanently alters SNB motoneuron number and soma size; in adulthood, androgens regulate dendritic and synaptic architecture. The present set of experiments investigates the influence of androgens on the development of SNB dendritic morphology. In normal males, SNB dendritic growth is biphasic, reaching exuberant lengths by the fourth postnatal week and then retracting to adult lengths by 7 weeks of age. This dendritic growth is androgen dependent--males castrated on postnatal day (P) 7 and given daily injections of testosterone propionate (TP) had exuberant dendritic lengths similar to those of normal males; dendritic length in oil-treated males remained at P7 levels. The early exuberant dendritic length was retained in TP-treated males through P49. The retraction of SNB dendrites after P28 is also influenced by androgens. Males castrated at P28 and given testosterone implants retained exuberant dendritic length at P49; blank-implanted males had significantly shorter dendritic lengths by P70. These results suggest that androgens are necessary for the early exuberant growth of SNB dendrites. Furthermore, the subsequent retraction of SNB dendrites may be halted when testosterone titers reach a critical level during puberty, stabilizing their adult length.

A human lymphocyte homing receptor, the hermes antigen, is related to cartilage proteoglycan core and link proteins

Lymphocyte interactions with high endothelial venules (HEV) during extravasation into lymphoid tissues involve an 85-95 kd class of lymphocyte surface glycoprotein(s), gp90Hermes (CD44). We report here the cloning of cDNA for gp90Hermes expressed in a mucosal HEV-binding B lymphoblastoid cell line, KCA. Northern hybridization revealed the presence of three invariant RNA bands at 1.5, 2.2, and 4.5 kb in mucosal HEV-, lymph node HEV-, or dual-binding cells. The deduced amino acid sequence predicts a mature protein with a C-terminal cytoplasmic tail, a hydrophobic transmembrane domain of 23 amino acids, and an N-terminal extracellular region of 248 amino acids. A proximal extracellular domain is the probable region of O-glycosylation and chondroitin sulfate linkage and displays at least two of the three immunodominant epitope clusters of native gp90Hermes. A distal region contains the majority of potential N-glycosylation sites and cysteines, and exhibits a striking homology to tandemly repeated domains of the cartilage link and proteoglycan core proteins. No significant similarities were found to the immunoglobulin, integrin, or cadherin gene families. Thus gp90Hermes represents a novel class of integral membrane protein involved in lymphocyte-endothelial cell interactions and lymphocyte homing.

Nucleotide sequence of rat haptoglobin cDNA. Characterization of the alpha beta-subunit junction region of prohaptoglobin

The biosynthesis of rat haptoglobin, a hetrotetrameric glycoprotein (alpha 2 beta 2), requires the post-translational cleavage of its glycosylated primary translation product (prohaptoglobin) into alpha- and beta-subunits (Hanley, J. M., Haugen, T. H., and Heath, E. C. (1983) J. Biol. Chem. 258, 7858-7869). To elucidate the site(s) at which proteolytic cleavage occurs in prohaptoglobin, we have isolated a recombinant plasmid whose cDNA insert encodes for the carboxyl terminus of the alpha-subunit, the alpha beta-subunit junction, and the beta-subunit region, and also the entire 3'-untranslated region (142 base pairs) and poly(A) tail (55 base pairs) of the mRNA. A single arginine residue was found at the alpha beta-subunit junction region -Val-Gln-Arg-Ile-Ile-Gly-Gly-of prohaptoglobin. The sequence homology of this region with serine protease precursors suggests that post-translational processing of prohaptoglobin involves cleavage of the Arg-Ile bond and extraction of the Arg residue. The rat beta-subunit shows a high degree (approximately 80%) of sequence homology with its human counterpart although it possesses only two of the four N-glycosylation sites present in human haptoglobin beta-subunit.

Lumbosacral transitional vertebrae and their relationship with lumbar extradural defects

The relationship between herniated lumbar disc and abnormalities of the transverse process of the lumbosacral junction was investigated. Two hundred consecutive patients with positive myelographic findings of herniated lumbar disc were reviewed. Sixty patients presented abnormalities of the transverse process to satisfy the criteria for lumbosacral transitional vertebra. A new classification of lumbosacral transitional vertebra is presented based upon the morphologic and clinical characteristics with respect to herniated nucleus pulposus. Type I represents a "forme fruste" of lumbosacral transitional vertebra and shows no difference in the incidence of the location of herniations. In types III and IV, there are no herniations at the level of the lumbosacral transitional vertebra and no increase in the incidence of herniations just proximal to the lumbosacral transitional vertebra. The Type II lumbosacral transitional vertebra presents herniated lumbar disc at the level of transition. It also presents a greater than normal incidence of herniations at the level just above the lumbosacral transitional vertebra.

Comparative ontogenesis of gamma-glutamyl transpeptidase in rat tissues

In rats, placental gamma glutamyl transpeptidase (GGTP) specific activity declined linearly during the last third of gestation. In contrast, the kidney enzyme activity progressively increased 15-fold. In the gut, peak activity was reached at mid-lactation (age 12 days). Hepatic GGTP levels were maximal during the foetal stage. Brain GGTP was negligible at birth and attained its highest specific activity at weaning.

Esophageal perforations: a 15 year experience

A review of 44 patients with 50 esophageal perforations from 1966 through 1980 is presented. The age span was 15 months to 94 years and the male to female ratio was 1 to 1. Each case was studied with regard to presentation, etiology, treatment and complications. Twenty-two cases of esophageal perforation followed instrumentation, including 6 secondary to Mosher bag dilatation for achalasia. Of the remainder, seven patients had spontaneous perforation, five had external trauma, five had intraoperative injury, two had caustic ingestion, and one each had foreign body ingestion, Zollinger-Ellison syndrome and an incarcerated paraesophageal hiatal hernia. Management was nonoperative in 12 patients, primary repair and drainage was performed in 23 patients, and 9 patients underwent drainage and diversion. This series plus 824 patients with esophageal perforation accumulated from a review of the literature emphasizes the importance of the influence of different methods of treatment and time lapse between occurrence and therapy. The type of perforation had no significance on this series. As a result of the experience gained from this series, a treatment protocol is proposed for the management of esophageal perforation.

Factor-dependent dissociation of wheat germ ribosomes

Ribosome dissociation factor has been found in wheat germ acetone powder extracts. Further purification of the crude extract by pH an ammonium sulfate fractionations, DEAE-cellulose and CM-Sephadex column chromatography has resulted in the separation of two active fractions. The possibility that ribosome dissociation activity exhibited by either fraction is due to protease or nuclease is considered unlikely, based on results of experiments involving ribosome dissociation kinetics, subunit structural integrity, and treatment with a serine protease inhibitor. Wheat germ ribosome dissociation factor is not species-specific. Dissociation factor from both fractions will promote the dissociation of Escherichia coli 70-S as well as Artemia salina 80-S ribosomes. Although both dissociation factor activities show the same dependence on K+ and Mg2+ for optimal activity, the two activities exhibit significant differences in their sensitivity to sulfhydryl reagents and heat, and in their dependence on incubation temperature for activity. Certain properties of both factors suggest that neither factor is initiation factor eIF-3; however, the possibility that one or both factors are subunits of initiation factor eIF-3 remains to be determined.

Guidelines for the management of lumbosacral spondylolisthesis associated with scoliosis

Lumbosacral spondylolisthesis, when it is associated with scoliosis, presents special problems which require special consideration in management. Lumbosacral spondylosisthesis associated with a major thoracic curve, presents two separate problems. Treatment of the lumbosacral spondylolisthesis depends upon the severity of the lesion and symptoms. The thoracic curve is treated as required, depending upon the severity of the scoliosis and the stage of spinal maturation. Lumbosacral spondylolisthesis associated with a thoracolumbar or lumbar curve requires treatment of the curves above, along with the spondylolisthesis. Do not fuse the lumbosacral joint in an uncorrected position.