Notch-Wnt signal crosstalk regulates proliferation and differentiation of osteoprogenitor cells during intramembranous bone healing.

Adult bone regeneration is orchestrated by the precise actions of osteoprogenitor cells (OPCs). However, the mechanisms by which OPC proliferation and differentiation are linked and thereby regulated are yet to be defined. Here, we present evidence that during intramembranous bone formation OPC proliferation is controlled by Notch signaling, while differentiation is initiated by activation of canonical Wnt signaling. The temporospatial separation of Notch and Wnt signal activation during the early stages of bone regeneration suggests crosstalk between the two pathways. In vitro and in vivo manipulation of the two essential pathways demonstrate that Wnt activation leads to initiation of osteogenic differentiation and at the same time inhibits Notch signaling, which results in termination of the proliferative phase. Here, we establish canonical Wnt signaling as a key regulator that facilitates the crosstalk between OPC proliferation and differentiation during intramembranous, primary bone healing.

Temporary inhibition of the plasminogen activator inhibits periosteal chondrogenesis and promotes periosteal osteogenesis during appendicular bone fracture healing.

INTRODUCTION: Aminocaproic acid is approved as an anti-fibrinolytic for use in joint replacement and spinal fusion surgeries to limit perioperative blood loss. Previous animal studies have demonstrated a pro-osteogenic effect of aminocaproic acid in spine fusion models. Here, we tested if aminocaproic acid enhances appendicular bone healing and we sought to uncover the effect of aminocaproic acid on osteoprogenitor cells (OPCs) during bone regeneration. METHODS: We employed a well-established murine femur fracture model in adult C57BL/6J mice after receiving two peri-operative injections of aminocaproic acid. Routine histological assays, biomechanical testing and micro-CT analyses were utilized to assess callus volume, and strength, progenitor cell proliferation, differentiation, and remodeling in vivo. Two disparate ectopic transplantation models were used to study the effect of the growth factor milieu within the early fracture hematoma on osteoprogenitor cell fate decisions. RESULTS: Aminocaproic acid treated femur fractures healed with a significantly smaller cartilaginous callus, and this effect was also observed in the ectopic transplantation assays. We hypothesized that aminocaproic acid treatment resulted in a stabilization of the early fracture hematoma, leading to a change in the growth factor milieu created by the early hematoma. Gene and protein expression analysis confirmed that aminocaproic acid treatment resulted in an increase in Wnt and BMP signaling and a decrease in TGF-ß-signaling, resulting in a shift from chondrogenic to osteogenic differentiation in this model of endochondral bone formation. CONCLUSION: These experiments demonstrate for the first time that inhibition of the plasminogen activator during fracture healing using aminocaproic acid leads to a change in cell fate decision of periosteal osteoprogenitor cells, with a predominance of osteogenic differentiation, resulting in a larger and stronger bony callus. These findings may offer a promising new use of aminocaproic acid, which is already FDA-approved and offers a very safe risk profile.

Galanin expression in adult human dorsal root ganglion neurons: initial observations.

Human dorsal root ganglia (DRGs) were obtained during various procedures and processed for single and double in situ hybridisation using oligonucleotide probes complementary to three peptide mRNAs. Some postmortem ganglia were also analysed. In donor (unlesioned) DRGs 12.5% of the neuron profiles (NPs) were galanin mRNA-positive (mRNA(+)), 47.5% calcitonin gene-related peptide (CGRP) mRNA(+) and 32.7% substance P mRNA(+). The corresponding percentages for cervical/thoracic DRGs from patients suffering from severe brachial plexus injury were 32.8%, 57.4% and 34.5%, respectively. In these DRGs a high proportion of the galanin mRNA(+) NPs contained CGRP mRNA and substance P mRNA. In DRGs from a patient with migraine-like pain a comparatively small proportion expressed galanin, whereas in DRGs from a herpes zoster patient galanin mRNA(+) NPs were comparatively more frequent. The results from human postmortem DRGs revealed only weak peptide mRNA signals. The present results demonstrate that galanin is expressed in DRGs not only in a number of animal species including monkey as previously shown, but also in a considerable proportion of human DRG neurons, often together with CGRP and substance P, and mostly in small neurons. Thus, galanin may play a role in processing of sensory information, especially pain, in human DRGs and dorsal horn. However, to what extent a similarly dramatic upregulation of galanin expression can be seen after peripheral nerve lesion in man, as has been reported for rat, mouse and monkey, remains to be analysed.

GDNF and NGF family members and receptors in human fetal and adult spinal cord and dorsal root ganglia.

We describe the expression of mRNA encoding ligands and receptors of members of the GDNF family and members of the neurotrophin family in the adult human spinal cord and dorsal root ganglia (DRG). Fetal human spinal cord and ganglia were investigated for the presence of ligands and receptors of the neurotrophin family. Tissues were collected from human organ donors and after routine elective abortions. Messenger RNA was found encoding RET, GFR alpha-1, BDNF, trkB, and trkC in the adult human spinal cord and BDNF, NT-3, p75, trkB, and trkC in the fetal human spinal cord. The percentage of adult human DRG cells expressing p75, trkA, trkB, or trkC was 57, 46, 29, and 24%, respectively, and that of DRG cells expressing RET, GFR alpha-1, GFR alpha-2, or GFR alpha-3 was 79, 20, 51, and 32%, respectively. GFR alpha-2 was expressed selectively in small, GFR alpha-3 principally in small and GFR alpha-1 and RET in both large and small adult human DRG neurons. p75 and trkB were expressed by a wide range of DRG neurons while trkA was expressed in most small diameter and trkC primarily in large DRG neurons. Fetal DRG cells were positive for the same probes as adult DRG cells except for NT-3, which was only found in fetal DRG cells. Messenger RNA species only expressed at detectable levels in fetal but not adult spinal cord tissues included GDNF, GFR alpha-2, NT-3, and p75. Notably, GFR alpha-2, which is expressed in the adult rat spinal cord, was not found in the adult human spinal cord.

The integration of individual therapy and family therapy in the treatment of child and adolescent psychiatric disorders.

Children influence families and families influence children. Individuals create a family, and a family is more than a sum of its individuals. These dialectic views are at the heart of the clinical application of the integration of individual and family therapy. Any attempt to treat the mental disorders of children and adolescents must consider both views and their treatment implications. The use of combined therapeutic modalities can offer more flexibility, specificity, and precision for the treatment process.

Assessment of the family. Systemic and developmental perspectives.

Why was Elizabeth the symptomatic family member? This challenging question is informed by the family assessment, which examines family process patterns, family structure, family history, and developmental challenges of individual family members and the family as a whole. Although the answer to this question may never be explained completely, the family assessment does contribute to the biopsychosocial formulation on which rational therapeutic intervention is based. The family assessment does not replace a clinical assessment of the identified patient. Rather, the use of the family assessment provides a greater breadth from which to view children and adolescents presenting complaints.

Parent management training.

As the estimates of prevalence and cost of mental health problems in our children continue to rise, it is incumbent on our society to have an effective and cost-efficient means to address this health crisis. Consistently, the research literature indicates that PMT offers great promise as an efficacious treatment of conduct-disordered children. There are recent studies of PMT's benefits as a preventive intervention that not only improves children's conduct but also positively affects parent-child relationships, mood, social competence, and school adjustment or performance. Although relatively untested, there are indications that PMT also could play an important adjunctive role in the treatment of internalizing disorders. As a curriculum-driven and didactic form of treatment, PMT is highly adaptable to various treatment and prevention contexts, and from a managed care perspective, PMT's structure allows its costs to be well defined and managed. Despite these positive attributes, however, few clinics systematically offer PMT as a treatment option, and third-party payers have been reluctant to cover its costs. Although it is conceded that much needs to be learned about the scope of PMT's effectiveness and the modifications that are necessary to improve its adaptability to high-risk families, it is proposed that PMT should join the mainstream of broadly available health care provisions for children and their families. This broad inclusion of PMT requires mental health educators to include PMT training as a standard part of provider training, requires that third-party payers include PMT as a covered service, and requires that local and federal governments support the proliferation of PMT in treatment and prevention initiatives.

Family therapy for eating disorders.

It is a perpetual source of debate whether dysfunctional family communication and relationship patterns cause eating disorders or the stress associated with raising a child with an eating disorder elicits such problems. Regardless, family therapy is a necessary component of any comprehensive biopsychosocial approach to the treatment of eating disorders. A careful assessment of the entire family, including the identified patient; his or her parents and siblings; the parents' marriage and families of origin; the child's emotional, social, and physical development; parental regulation of developmental stages; and communication patterns is mandatory. Family therapy for eating-disordered patients attempts to facilitate the elimination of potentially life-threatening symptoms and begin a therapeutic process of change within the entire family. Research has shown significant support for the use of family therapy in this population, but well-controlled treatment outcome research remains somewhat limited.

NOGO mRNA expression in adult and fetal human and rat nervous tissue and in weight drop injury.

Nogo is a myelin-associated protein known to inhibit growth of neurites. In order to understand possible physiological roles of Nogo, we performed in situ hybridization using rat and human probes complementary to a Nogo-A-specific sequence and a sequence shared by all known Nogo transcripts recognizing nogo-A, -B, and -C. We studied the cellular distribution of nogo-mRNA in fetal and adult human and rat tissues, with a focus on the spinal cord and ganglia. Rat mRNA expression was also studied in a spinal cord weight-drop model and in animals exposed to kainic acid. In human fetal tissue, nogo-A was strongly expressed in the ventral two-thirds of the spinal cord, the dorsal root ganglia, and autonomic ganglia. Similarly, nogo-A mRNA expression was observed in the adult human spinal cord and ganglia. High levels of nogo-A message were observed in neurons, such as motor neurons and sensory ganglia neurons. The distribution of nogo message in rats resembled that seen in human tissues. Thus, nogo mRNA was expressed in neurons and oligodendrocytes, but not astrocytes or Schwann cells. In addition, expression of nogo-A mRNA was observed in human and rat developing muscle tissue. High level of nogo-mRNA were also expressed in the rat trigeminal ganglion and trigeminal pontine nucleus. In fetal rats the adrenal gland and cell clusters in the liver were positive for the nogo-ABC pan-probe, but negative for the nogo-A probe. While neurons in the adult rat brain were generally positive, very prominent nogo-A mRNA and nogo-ABC mRNA signals were obtained from neurons of the hippocampus, piriform cortex, the red nucleus, and the oculomotor nucleus. Nogo-A mRNA expression was markedly reduced in the epicenter of a lesion in the spinal cord of adult rats 6 and 24 h after a weight-drop injury, while no perifocal upregulation of nogo mRNA was seen. No obvious change of nogo expression was detected in kainic acid exposed animals. In conclusion our in situ hybridization study has demonstrated widespread expression of nogo mRNA in the fetal, developing and adult nervous system of rat and man. In addition to oligodendroglial cells, high levels of nogo-A mRNA expression were found in neurons, raising important questions about the function of neuronal nogo mRNA. No obvious regulation of nogo was detected following injury.

A spinal thecal sac constriction model supports the theory that induced pressure gradients in the cord cause edema and cyst formation.

OBJECTIVE: Spinal cord cysts are a devastating condition that occur secondary to obstructions of the spinal canal, which may be caused by congenital malformations, trauma, spinal canal stenosis, tumors, meningitis, or arachnoiditis. A hypothesis that could explain how spinal cord cysts form in these situations has been presented recently. Therefore, a novel spinal thecal sac constriction model was implemented to test various aspects of this hypothesis. METHODS: Thecal sac constriction was achieved by subjecting rats to an extradural silk ligature at the T8 spinal cord level. Rats with complete spinal cord transection served as a second model for comparison. The animals underwent high-resolution magnetic resonance imaging and histological analysis. RESULTS: Thecal sac constriction caused edema cranial and caudal to the ligation within 3 weeks, and cysts developed after 8 to 13 weeks. In contrast, cysts in rats with spinal cord transection were located predominantly in the cranial spinal cord. Histological sections of spinal cords confirmed the magnetic resonance imaging results. CONCLUSION: Magnetic resonance imaging provided the specific advantage of enabling characterization of events as they occurred repeatedly over time in the spinal cords of individual living animals. The spinal thecal sac constriction model proved useful for investigation of features of the cerebrospinal fluid pulse pressure theory. Edema and cyst distributions were in accordance with this theory. We conclude that induced intramedullary pressure gradients originating from the cerebrospinal fluid pulse pressure may underlie cyst formation in the vicinity of spinal canal obstructions and that cysts are preceded by edema.

A characteristic serpin cleavage product of thyroxine-binding globulin appears in sepsis sera.

T4-binding globulin (TBG), the principal thyroid hormone-binding protein of serum, is a member of the serine protease inhibitor (serpin) superfamily. We report a characteristic serpin cleavage product of TBG in sepsis sera. At 49-50 kDa, the TBG remnant is 4-5 kDa smaller than the intact protein and is the same molecular mass as a TBG cleavage product produced by incubation with polymorphonuclear elastase. Incubation with polymorphonuclear leukocytes also produces the 49- to 50-kDa remnant, and this proteolysis is stimulated by zymosan activation. Polymorphonuclear cell cleavage of TBG increases the ratio of free/bound T4. As previously described, in vitro cleavage of TBG by elastase also increases free/bound T4. These findings are consistent with the hypothesis that serine proteases present at inflammatory sites cleave TBG, releasing its hormonal ligands.

Functional MRI at 4.7 tesla of the rat brain during electric stimulation of forepaw, hindpaw, or tail in single- and multislice experiments.

Stimulation of peripheral nerves activates corresponding regions in sensorimotor cortex. We have applied functional magnetic resonance imaging (fMRI) techniques to monitor activated brain regions by means of measuring changes of blood oxygenation level-dependent contrast during electric stimulation of the forepaw, hindpaw, or tail in rats. During alpha-chloralose anesthesia, artificial respiration, and complete muscle relaxation, stimulations were delivered at 3 Hz via subcutaneous bipolar electrodes with 500-microseconds-current pulses of 0.2-2.0 mA. Single- or multislice gradient echo images were collected during recording sessions consisting of five alternating rest and stimulation periods. Stimulation of the right and left forepaws and hindpaws repeatedly led to robust activation of the contralateral sensorimotor cortex. There was a significant correlation (P < 0.05) between current pulse strength and amount of activation of the sensory cortex during forepaw stimulation. The center of the main cortical representation of the forepaw was situated 3.4 mm lateral to the midline and 5 mm posterior to the rhinal fissure. The main representation of the hindpaw was 2.0 mm lateral to the midline and 6 mm posterior to the rhinal fissure. Tail stimulation gave rise to a strikingly extended bilateral cortical activation, localized along the midline in medial parietal and frontal cortex 4 and 5 mm posterior to the rhinal fissure. In conclusion, the experiments provide evidence that peripheral nerve stimulation induces a fMRI signal in the respective division of the somatosensory cortex in a stimulus-related manner. The marked cortical activation elicited by tail stimulation underlines the key importance of the tail.

Data-gathering tools for "real world" clinical settings: a multisite feasibility study.

OBJECTIVE: To determine the mental health needs and optimal treatments for children and families in "real world" settings, data-gathering strategies are needed that can be easily implemented across a variety of clinical settings. To address this need, the authors developed and piloted a "clinician-friendly" questionnaire that includes demographic, psychosocial, medical, and family history variables, such as those routinely gathered in standard clinical evaluations. METHOD: Optical scanning technology was used to encode data from more than 1,900 children, including 1,458 consecutive referrals in four military child psychiatry clinics, 285 consecutive admissions to a civilian psychiatric state hospital, 71 pediatric patients, and a community sample of 113 children. RESULTS: Despite geographic and logistic obstacles, clinical data were reliably obtained across multiple settings. Data analyses revealed meaningful differences across samples in subjects' presenting complaints, and a range of psychosocial, demographic, and background variables. Data were characterized by an apparently high degree of accuracy and completeness. CONCLUSIONS: Findings illustrate the importance and feasibility of standardized data-gathering approaches in routine clinical settings and clarify the hazards as well as the opportunities afforded by these research approaches. Such data-gathering tools appear to have significant merit and deserve further implementation and testing across a range of clinical and research settings.

Meeting infection control standards in the OR.

Quality health care is associated with the absence of negative outcomes in patients. Institutions realize that quality cannot be assured but it can be assessed and methods can be developed to improve patient care. Many heath care institutions, therefore, have begun the conceptual transition from quality assurance model to principles of continuous quality improvement (CQI). This article describes a CQI project that was developed to enhance infection control standards in OR settings. The project involved three phases: development of a survey tool, implementation of an environmental assessment and monitoring model, and transfer of the model to OR staff members. Five months after implementation of the model, the chi-square test revealed there was a significant improvement in compliance (chi 2 = 5.0, P < .03). After 22 months of using the model, compliance to infection control standards remains high and OR staff members have taken ownership of the model by incorporating it into their departmental CQI process.

The reported prevalence of physical and sexual abuse among a sample of children and adolescents at a public psychiatric hospital.

In this retrospective analysis of inpatient charts, a total of 298 children and adolescents admitted to a public psychiatric hospital over a 1-year period were examined for the prevalence of reported histories of physical or sexual abuse. Physical abuse was reported in 15% of the cases, while sexual abuse occurred in 13%. A variety of comparisons were made examining possible differences in gender, age, race, diagnosis, and personality trait disturbance among the abused and nonabused patients. Relative to known prevalence rates as reported to child protective agencies, physical or sexual abuse occurred much more frequently among our sample of patients, suggesting the need for careful assessment of such histories upon admission and during treatment.