Circadian regulation of the Drosophila astrocyte transcriptome.

Recent studies have demonstrated that astrocytes cooperate with neurons of the brain to mediate circadian control of many rhythmic processes including locomotor activity and sleep. Transcriptional profiling studies have described the overall rhythmic landscape of the brain, but few have employed approaches that reveal heterogeneous, cell-type specific rhythms of the brain. Using cell-specific isolation of ribosome-bound RNAs in Drosophila, we constructed the first circadian "translatome" for astrocytes. This analysis identified 293 "cycling genes" in astrocytes, most with mammalian orthologs. A subsequent behavioral genetic screen identified a number of genes whose expression is required in astrocytes for normal sleep behavior. In particular, we show that certain genes known to regulate fly innate immune responses are also required for normal sleep patterns.

Feasibility of Actigraphy for Evaluating Sleep and Daytime Physical Activity in Children with Autism Spectrum Disorder.

This research evaluated the feasibility of actigraphy to measure sleep and physical activity in children (ages 2-8 years) with autism spectrum disorder (ASD). We also explored associations between sleep and physical activity. Validated screening measures established eligibility. Questionnaires, diaries, and 5 days and 5 nights of actigraphy monitoring were used to collect data. Of the 32 children enrolled, 27 (84.4%) completed actigraphy monitoring. Based on the median steps per day, children with high physical activity had lower total sleep time and more disruptive behaviors than children with low physical activity. Findings support the feasibility of using actigraphy to measure sleep and physical activity in children with ASD. Larger studies are needed to evaluate interactions of physical activity on sleep in this population.

Qualitative Exploration Toward the Development of a Parent-Rated Scale for Insomnia in Children with Autism Spectrum Disorder.

Toward the development of a new parent-rating for insomnia, this multi-site qualitative study explored sleep problems and related impacts in children with autism spectrum disorder (ASD) and their families. To ensure content validity of the measure, we conducted six focus groups with caregivers (N = 25) of 24 children (age 3 to 18 years) with ASD. Based on parent report, all children had a history of mild or greater insomnia. The focus group transcripts were systematically coded to identify major themes. Verbatim comments from caretakers were used to generate 134 candidate items. Further review by the research team and an expert panel followed by individual cognitive interviews with 12 parents reduced the item bank to 40. The thematic analysis of focus group transcripts identified 7 categories: (1) Trouble falling asleep; (2) trouble staying asleep; (3) early morning waking; (4) bedtime routines; (5) parental strategies for bedtime management; (6) impact of sleep problems on the child; and (7) impact of sleep problems on the family. The Flesch Kincaid Grade Level of the 40-item version was 7.2 (seventh grade reading level). Insomnia in children with ASD shares features in common with insomnia in the general pediatric population. However, perhaps owing to autistic features such as insistence on sameness, sensory sensitivities, communication impairments, insomnia in children with ASD appears to have unique behavioral manifestations. Content validity and item clarity of the 40-item bank were supported by expert panel review and cognitive interviews with caregivers of children with ASD.

Olfactomedin-4 + neutrophils exacerbate intestinal epithelial damage and worsen host survival after Clostridioides difficile infection.

Neutrophils are key first responders to Clostridioides difficile infection (CDI). Excessive tissue and blood neutrophils are associated with worse histopathology and adverse outcomes, however their functional role during CDI remains poorly defined. Utilizing intestinal epithelial cell (IEC)-neutrophil co-cultures and a pre-clinical animal model of CDI, we show that neutrophils exacerbate C. difficile -induced IEC injury. We utilized cutting-edge single-cell transcriptomics to illuminate neutrophil subtypes and biological pathways that could exacerbate CDI-associated IEC damage. As such, we have established the first transcriptomics atlas of bone marrow (BM), blood, and colonic neutrophils after CDI. We found that CDI altered the developmental trajectory of BM and blood neutrophils towards populations that exhibit gene signatures associated with pro-inflammatory responses and neutrophil-mediated tissue damage. Similarly, the transcriptomic signature of colonic neutrophils was consistent with hyper-inflammatory and highly differentiated cells that had amplified expression of cytokine-mediated signaling and degranulation priming genes. One of the top 10 variable features in colonic neutrophils was the gene for neutrophil glycoprotein, Olfactomedin 4 (OLFM4). CDI enhanced OLFM4 mRNA and protein expression in neutrophils, and OLFM4 + cells aggregated to areas of severe IEC damage. Compared to uninfected controls, both humans and mice with CDI had higher concentrations of circulating OLFM4; and in mice, OLFM4 deficiency resulted in faster recovery and better survival after infection. Collectively, these studies provide novel insights into neutrophil-mediated pathology after CDI and highlight the pathogenic role of OLFM4 + neutrophils in regulating CDI-induced IEC damage. One Sentence Summary: Utilizing single-cell transcriptomics, IEC-epithelial co-cultures, and pre-clinical models of CDI, we have identified a subset of neutrophils that are marked by OLFM4 expression as pathogenic determinants of IEC barrier damage after CDI.

A Simulated Shift Work Schedule Does Not Increase DNA Double-Strand Break Repair by NHEJ in the Drosophila Rr3 System.

Long-term shift work is widely believed to increase the risk of certain cancers, but conflicting findings between studies render this association unclear. Evidence of interplay between the circadian clock, cell cycle regulation, and DNA damage detection machinery suggests the possibility that circadian rhythm disruption consequent to shift work could alter the DNA double-strand break (DSB) repair pathway usage to favor mutagenic non-homologous end-joining (NHEJ) repair. To test this hypothesis, we compared relative usage of NHEJ and single-strand annealing (SSA) repair of a complementary ended chromosomal double-stranded break using the Repair Reporter 3 (Rr3) system in Drosophila between flies reared on 12:12 and 8:8 (simulated shift work) light:dark schedules. Actimetric analysis showed that the 8:8 light:dark schedule effectively disrupted the rhythms in locomotor output. Inaccurate NHEJ repair was not a frequent outcome in this system overall, and no significant difference was seen in the usage of NHEJ or SSA repair between the control and simulated shift work schedules. We conclude that this circadian disruption regimen does not alter the usage of mutagenic NHEJ DSB repair in the Drosophila male pre-meiotic germline, in the context of the Rr3 system.

Characterizing Sleep in Adolescents and Adults with Autism Spectrum Disorders.

We studied 28 adolescents/young adults with autism spectrum disorders (ASD) and 13 age/sex matched individuals of typical development (TD). Structured sleep histories, validated questionnaires, actigraphy (4 weeks), and salivary cortisol and melatonin (4 days each) were collected. Compared to those with TD, adolescents/young adults with ASD had longer sleep latencies and more difficulty going to bed and falling asleep. Morning cortisol, evening cortisol, and the morning-evening difference in cortisol did not differ by diagnosis (ASD vs. TD). Dim light melatonin onsets (DLMOs) averaged across participants were not different for the ASD and TD participants. Average participant scores indicated aspects of poor sleep hygiene in both groups. Insomnia in ASD is multifactorial and not solely related to physiological factors.

Changes in the fracture toughness of bone may not be reflected in its mineral density, porosity, and tensile properties.

Age-related changes in the skeleton often lead to an increase in the susceptibility of bone to fracture. Such changes most likely occur in the constituents of bone, namely, the mineral and organic phases, and in their spatial arrangement manifested as orientation and microstructure. In the past, however, bone loss or decline in bone mineral density has been considered to be the major contributing factor for the increased risk of bone fractures, and elastic modulus and ultimate strength have been commonly used to assess bone quality and strength. However, whether these properties provide sufficient information regarding the likelihood of bone to fracture remains debatable. Using a novel fracture toughness test, which measures the energy or stress intensity required to propagate a crack within a material, the objective of this study was to investigate if the mineral density and mechanical properties of bone can accurately predict bone fragility as measured by fracture toughness. Changes in fracture toughness (K(IC)), bone mineral density (BMD), elastic modulus (E), yield and ultimate strength (sigma y and sigma s), porosity (P0), and microhardness (Hv) of bone were examined as a function of age in a baboon model. With increasing age, the fracture toughness of bone decreased, and its microhardness increased. However, no significant changes were found in BMD, E, P0, sigma y, and sigma s as a function of age. In addition, simple regression analyses revealed no significant correlation between bone fracture toughness and the other parameters, except for microhardness of bone. The results of this study indicate that changes in bone fracture toughness may not be necessarily reflected in its mineral density, porosity, elastic modulus, yield strength, and ultimate strength.

Antibiotic therapy of osteomyelitis in outpatients.

The therapy of osteomyelitis utilizing 481 courses of intravenous antibiotics in outpatients was analyzed to identify the types of bone infection most frequently treated by this form of therapy. The efficacy of this form of treatment is also discussed.

The temporomandibular joint.

MRI is the procedure of choice for diagnosing most internal derangements. MRI provides images that not only demonstrate bony detail but show excellent representation of soft tissues in both anatomic and semifunctional relationships. MRI does not use ionizing radiation and has no known adverse effects. Multiplanar imaging allows a three-dimensional analysis of the TMJ, providing a more complete assessment of the condyle, articular disc, fossa relationships. Whenever capsular adhesions or disc perforations are suspected and are not demonstrated with MRI, then arthrography should be performed.

Chronic morphine administration: plasma levels and withdrawal syndrome in rats.

Morphine, administered to Sprague-Dawley rats over a period of 65 hr either by the simultaneous implantation of two 75 mg pellets, or by a series of twice daily 20 or 30 mg/kg injections, produced dependence as indicated by the precipitation of the abstinence syndrome with the antagonist, naloxone. Plasma morphine levels, analyzed fluorometrically at various times during the treatment procedures, revealed peak concentrations that were 3 or 4 fold higher for injected animals than the maximum steady-state level established in the pellet-implanted animals. The calculated plasma concentration of the drug over time was not statistically different for the groups. It is noted that although the 2 methods of morphine administration produce a qualitatively identical dependent state, the pellet implantation technique causes greater weight loss and a higher incidence of jumping and wet-dog shakes during withdrawal.

Comparison of nickel-titanium and stainless steel hand-file instrumentation using computed tomography.

Computed tomography was used to evaluate root canals prepared by nickel-titanium (Ni-Ti) hand and stainless steel hand endodontic instruments. Thirty-six single-rooted teeth of similar shape and canal size were divided into three groups. The teeth were scanned by computed tomography before instrumentation. In group A, canals were instrumented using a quarter turn/pull technique with K-flex files. In group B, canals were prepared with Ni-Ti hand files (Mity files) using the same technique as group A. Group C was prepared with Ni-Ti hand files (Mity files) using a reaming technique. Instrumented teeth were again scanned using computed tomography, and reformated images of the uninstrumented canals were compared with images of the instrumented canals. Ni-Ti instruments (Mity file) used in a reaming technique caused significantly less canal transportation (p < 0.05), removed significantly less volume of dentin (p < 0.05), required less instrumentation time (p < 0.05), and produced more centered and rounder canal preparations than K-flex stainless steel files used in a quarter turn/pull technique. The computed tomography imaging system used in this study provided a repeatable, noninvasive method of evaluating certain aspects of endodontic instrumentation.

Long-term assessment of early alveolar bone grafts using three-dimensional computer-assisted tomography: a pilot study.

Fifteen patients with complete unilateral cleft lip and palate who had primary alveolar bone grafting were studied with computer-assisted tomography at a mean age of 12 years. Keeping the maxillary alveolar crest parallel to the plane of the scan, 1.5-mm cuts of the maxilla were made from the infraorbital rim to the gingival third of the crowns of the teeth. A single operator reformatted the data into three-dimensional images using the Maxiview 3200 computer workstation. This allowed examination of the position, size, and spatial relationship of the grafted area and quantification of the amount of bone coverage of root surface and bone height of the alveolus in or adjacent to the graft site. Ten patients showed a lateral incisor in the line of the cleft. The average bony coverage of these tooth roots was 76.5 percent. In the five patients in whom there was lateral incisor agenesis, the canine root had average bony coverage of 82.6 percent. The average height of bone at the lateral incisor was 8.7 mm; at the canine, 14.1 mm. In two patients in whom there was only 42 percent tooth root coverage, the teeth were still viable, stable, and without mobility. Computed tomographic (CT) scans of the 15 patients demonstrated good graft survival with adequate volume. The functional and aesthetic status of the dentition in the area of the cleft also was demonstrated.

Short-term changes of condylar position after sagittal split osteotomy for mandibular advancement.

OBJECTIVE: The goal of this study was to quantify condylar position changes after mandibular advancement surgery with rigid fixation (screws). Radiographic changes in condylar position were determined in all planes (X, Y, and Z). Computed tomography with image reconstruction was used. STUDY DESIGN: A consecutive population of patients who elected to have rigid fixation for surgical stabilization method were studied (n = 21). Computed tomography data were acquired in the axial plane through use of abutting 1.5-mm-thick slices. Data acquisition occurred 1 week preoperatively and 8 weeks postoperatively. Measurements were made from 2-dimensional reconstructions. RESULTS: The averages were as follows: lateral displacement from midline, 1.2 mm (55% of patients); medial displacement from midline, 1.5 mm (45% of patients; range, 3.2 mm); condyle angle increase from coronal plane, 3.5 degrees (60% of patients); condyle angle decrease from coronal, 4.3 degrees (40% of patients; range, 8.5 degrees); superior rotation of proximal segment, 3.2 degrees (39% of patients); inferior rotation of proximal segment, 8.6 degrees (61% of patients; range, 15.6 degrees); superior displacement, 1.2 mm (60% of patients); inferior displacement, 1.0 mm (40% of patients; range, 2.5 mm); anterior displacement, 1.6 mm (33% of patients); posterior displacement, 1.6 mm (67% of patients; range, 2.8 mm). CONCLUSIONS: Changes occurred in all planes, but the most common postoperative condyle position was more lateral; with increased angle, the coronoid process was higher and the condyle was more superior and posterior in the fossa.

Magnetic resonance imaging: practical theory and clinical relevance.

Magnetic resonance imaging can be a valuable diagnostic tool. Some fundamental concepts behind MRI are discussed, using clinical cases to illustrate the potential of this imaging system.

Hemifacial microsomia. Etiology, diagnosis and treatment.

BACKGROUND: Three percent of all newborns have significant structural anomalies. Hemifacial microsomia, or HFM, is the second most common facial anomaly, second only to cleft lip and palate. New therapeutic and clinical management techniques offer promising interventions that can allow many patients to have more normal childhoods at earlier ages. DESCRIPTION: Due to a unilateral deficiency of the mandible and lower face, patients who have HFM have specific dental needs that require restorative, orthodontic and surgical correction. CLINICAL IMPLICATIONS: Oral and maxillofacial malformations present diagnostic and treatment challenges unique to the dental profession. The etiology, diagnosis and treatment modalities discussed in this article can be used to help effectively rehabilitate patients who have HFM.

Dentistry's role in the recognition and reporting of domestic violence, abuse, and neglect.

Domestic violence is epidemic in western society. Child abuse, intimate partner abuse, and elder abuse victims often have signs of injury that are readily visible to dentists. Dentists have a moral and legal obligation to recognize and report suspected abuse. This article offers information and illustrations to assist in diagnosing abuse. Reporting guidelines and legal obligation information sources for every state in the United States are included.

Clinical evaluation of anorganic bovine bone xenograft with a bioabsorbable collagen barrier in the treatment of molar furcation defects.

The purpose of this study was to compare Bio-Oss (BO), an anorganic bovine bone xenograft, in combination with Bio-Gide (BG), a bioabsorbable collagen barrier, to open-flap debridement (OFD) surgery in human mandibular Class II furcation defects. A total of 31 furcations (18 treatment, 13 control) in 21 patients were treated. There was a statistically significant improvement in most clinical indices for the BO/BG group, with minimal improvement noted for the OFD group. Vertical probing depth reduction of 2.0 mm and horizontal probing depth reduction of 2.2 mm were noted for the BO/BG group, with 0.3 mm and 0.2 mm reductions, respectively, noted for OFD. Hard tissue measurements showed 2.0 mm of vertical furcation bone fill for BO/BG and 0.5 mm for OFD. The BO/BG group had 3.0 mm of horizontal furcation bone fill, and the OFD group had 0.9 mm. The BO/BG group had a defect resolution of 82.7%; 42.5% was noted for the OFD group. There was a statistically significant difference between BO/BG and OFD in all soft and hard tissue measurements with the exception of attachment level, recession, and alveolar crest resorption.

A feasibility study evaluating rhBMP-2/absorbable collagen sponge for maxillary sinus floor augmentation.

This 16-week open-label study assessed the safety and technical feasibility of implanting human recombinant bone morphogenetic protein-2 delivered on an absorbable collagen sponge (rhBMP-2/ACS) for two-stage maxillary floor sinus augmentation. This first use of rhBMP-2/ACS in human clinical maxillary sinus floor augmentation included 12 patients with inadequate bone height in the posterior maxilla. The total delivered dose of rhBMP-2 implanted varied from 1.77 to 3.40 mg per patient. The rhBMP-2/ACS device was easily handled. Significant bone growth was documented by computerized tomographic scans in all evaluable patients (11/12). The overall mean height response for the maxillary sinus floor augmentation was 8.51 mm (95% confidence interval 6.07 to 10.95). There were no serious or unexpected immunologic or adverse effects and no clinically significant changes in complete blood counts, blood chemistries, or urinalysis results. The most frequent adverse effects were facial edema, oral erythema, pain, and rhinitis. Eleven patients have received dental implants and follow-up examinations are still being conducted. Histologic examinations of core bone biopsies obtained at the time of dental implant placement confirmed the quality of the bone induced by rhBMP-2/ACS. These results tend to indicate that rhBMP-2/ACS may provide an acceptable alternative to traditional bone grafts and bone substitutes for maxillary sinus floor augmentation procedures in humans.

A feasibility study evaluating rhBMP-2/absorbable collagen sponge device for local alveolar ridge preservation or augmentation.

This two-center human clinical trial evaluated recombinant human bone morphogenetic protein-2 delivered in an absorbable collagen sponge (rhBMP-2/ACS) for either alveolar ridge preservation after tooth extraction or augmentation of localized osseous defects. This 24-month study comprised two parts: a 4-month acute safety and bone induction period (Part I) followed by a 20-month, osseointegration, functional restoration, and long-term safety evaluation (Part II). The primary objective of Part I, discussed in this article, was to evaluate the short-term safety and technical feasibility of the rhBMP-2 device implantation. Twelve patients (six preservation and six augmentation) were enrolled in the investigation. Patient safety was monitored by oral examinations, radiographs, and the collection of blood samples to measure serum chemistries, hematology, and potential antibody formation. Technical feasibility was evaluated by collecting information relating to the handling properties of the rhBMP-2/ACS device. The ability of various evaluative tools to measure the bone-inducing activity of the rhBMP-2/ACS device was also assessed. The clinical results suggested that rhBMP-2/ACS was well tolerated locally and systemically, with no serious adverse events. The device was found to be easily handled and adapted to the ridge and extraction socket. Using direct measurements, all sites demonstrated firmness and fullness to palpation at 4 weeks; however, a loss of volume was noted in some treatment areas between 4 and 8 weeks. Augmentation of the alveolar ridge was not observed in the patients as assessed by the evaluation techniques. This trial indicated that the use of rhBMP-2/ACS to preserve alveolar ridge after tooth extraction or augmentation of localized defects is safe and feasible. Bone fill was observed in all alveolar sockets filled with the rhBMP-2 device.

Health promotion and disease prevention for the international traveler.

International travel is becoming increasingly popular with Americans, whether for business or pleasure. Approximately 10 to 15 million U.S. citizens travel abroad each year, and more than 8 million of these travel to developing nations. Travelers risk exposure to viral, bacterial and parasitic diseases not often encountered in the United States. Clients planning an international journey should be encouraged to obtain advice from their primary care practitioner. This article reviews the health care needs of the international traveler, including predeparture evaluation, required and recommended immunizations, and advice on disease-prevention measures.