Noncontact speckle contrast diffuse correlation tomography of blood flow distributions in tissues with arbitrary geometries

A noncontact electron multiplying charge-coupled-device (EMCCD)-based speckle contrast diffuse correlation tomography (scDCT) technology has been recently developed in our laboratory, allowing for noninvasive three-dimensional measurement of tissue blood flow distributions. One major remaining constraint in the scDCT is the assumption of a semi-infinite tissue volume with a flat surface, which affects the image reconstruction accuracy for tissues with irregular geometries. An advanced photometric stereo technique (PST) was integrated into the scDCT system to obtain the surface geometry in real time for image reconstruction. Computer simulations demonstrated that a priori knowledge of tissue surface geometry is crucial for precisely reconstructing the anomaly with blood flow contrast. Importantly, the innovative integration design with one single-EMCCD camera for both PST and scDCT data collection obviates the need for offline alignment of sources and detectors on the tissue boundary. The in vivo imaging capability of the updated scDCT is demonstrated by imaging dynamic changes in forearm blood flow distribution during a cuff-occlusion procedure. The feasibility and safety in clinical use are evidenced by intraoperative imaging of mastectomy skin flaps and comparison with fluorescence angiography.

Use of the MatrixWAVE™ system with dentures to establish maxillomandibular fixation in edentulous patients

Various methods have been described to establish maxillomandibular fixation in the treatment of fractures of atrophic, edentulous mandibles. We used the Synthes MatrixWAVE™ system (DePuy Synthes) in combination with dentures in two patients with fractured, edentulous, atrophic mandibles. Fixation was maintained for fractures that were not amenable to, or did not require, open reduction and internal fixation, and the mandibles were both well-healed and had good function at the end of treatment.

Symptomatic Nonsyndromic Pancarpal Coalition: Report of a Rare Case and Review of the Literature

Carpal coalition, the union of 2 or more carpal bones, can be congenital or acquired. Congenital, nonsyndromic carpal coalition usually presents in otherwise healthy individuals. The most common coalition is between the lunate and the triquetrum, followed by the capitate and the hamate. Pancarpal coalition, or coalition of all or most of the bones of the carpus, is an extremely rare finding and usually occurs as part of a syndrome. We present a nonsyndromic case of this rare entity, in a 28-year-old woman of West African descent, with symptoms of left hand and wrist pain. Our literature review revealed only 1 other reported case of isolated, nonsyndromic symptomatic pancarpal coalition.

Executive Function and Adaptive Behavior in Muenke Syndrome

OBJECTIVE

To investigate executive function and adaptive behavior in individuals with Muenke syndrome using validated instruments with a normative population and unaffected siblings as controls.

STUDY DESIGN

Participants in this cross-sectional study included individuals with Muenke syndrome (P250R mutation in FGFR3) and their mutation-negative siblings. Participants completed validated assessments of executive functioning (Behavior Rating Inventory of Executive Function [BRIEF]) and adaptive behavior skills (Adaptive Behavior Assessment System, Second Edition [ABAS-II]).

RESULTS

Forty-four with a positive FGFR3 mutation, median age 9 years, range 7 months to 52 years were enrolled. In addition, 10 unaffected siblings served as controls (5 males, 5 females; median age, 13 years; range, 3-18 years). For the General Executive Composite scale of the BRIEF, 32.1% of the cohort had scores greater than +1.5 SD, signifying potential clinical significance. For the General Adaptive Composite of the ABAS-II, 28.2% of affected individuals scored in the 3rd-8th percentile of the normative population, and 56.4% were below the average category (<25th percentile). Multiple regression analysis did not identify craniosynostosis as a predictor of BRIEF (P = .70) or ABAS-II scores (P = .70). In the sibling pair analysis, affected siblings performed significantly poorer on the BRIEF General Executive Composite and the ABAS-II General Adaptive Composite.

CONCLUSION

Individuals with Muenke syndrome are at an increased risk for developing adaptive and executive function behavioral changes compared with a normative population and unaffected siblings.

Hearing loss in syndromic craniosynostoses: otologic manifestations and clinical findings

OBJECTIVE

This review addresses hearing loss as it occurs and has been reported in Muenke syndrome as well as six additional FGFR related craniosynostosis syndromes (Apert syndrome, Pfeiffer syndrome, Crouzon syndrome, Beare-Stevenson syndrome, Crouzon syndrome with acanthosis nigricans, and Jackson-Weiss syndrome.

DATA SOURCES

Pub-Med, Medline, Cochrane Database, Science Direct, NLM Catalog.

REVIEW METHODS

A Medline search was conducted to find all reported cases of the 7 FGFR related syndromic craniosynostosis. Special attention was paid to literature that reported hearing findings and the audiology literature.

RESULTS

Hearing loss occurs in variable percentage as a component part of all FGFR related craniosynostosis syndromes. Our literature review revealed the following incidences of hearing loss in FGFR craniosynostoses: 61% in Muenke syndrome, 80% in Apert Syndrome, 92% in Pfeiffer syndrome, 74% in Crouzon syndrome, 68% in Jackson Weiss syndrome, 4% in Beare Stevenson syndrome and 14% in Crouzon syndrome with Acanthosis Nigricans. The majority of the hearing loss is a conductive hearing loss, with the exception of Muenke syndrome where the majority of patients have a sensorineural hearing loss and Crouzon syndrome where almost half of patients have a pure or component of sensorineural hearing loss.

CONCLUSION

This manuscript presents a diagnostic and management algorithm for patients with syndromic craniosynostosis. It will aid clinicians in treating these patients and further, the recognition of a possible syndrome in patients with hearing loss who also have syndromic features.

Hearing loss in syndromic craniosynostoses: introduction and consideration of mechanisms

PURPOSE

There are a number of craniosynostosis syndromes with hearing loss-including Muenke, Apert, Pfeiffer, Crouzon, Beare-Stevenson, Crouzon with acanthosis nigricans, and Jackson-Weiss syndromes-that result from mutations in the fibroblast growth factor receptor (FGFR) genes. Studies of FGFRs and their ligands, fibroblast growth factors (FGFs), have revealed clues to the precise contribution of aberrant FGFR signaling to inner ear morphogenesis and the hearing loss encountered in craniosynostoses. The purpose of this article is to review basic studies of FGFRs with emphasis on their function and expression in the inner ear and surrounding structures.

METHOD

A Medline search was performed to find basic science articles regarding FGFR, their ligands, and their expression and relevant mouse models. Additional items searched included clinical descriptions and studies of individuals with FGFR-related craniosynostosis syndromes.

RESULTS

The FGF signaling pathway is essential for the morphogensis and proper function of the inner ear and auditory sensory epithelium.

CONCLUSION

The variable auditory phenotypes seen in individuals with Muenke syndrome may have a genetic basis, likely due to multiple interacting factors in the genetic environment or modifying factors. Further analysis and studies of mouse models of Muenke syndrome, in particular, may provide clues to the specific effects of the defining mutation in FGFR3 in the inner ear not only at birth but also into adulthood. In particular, investigations into these models may give insight into the variable expression and incomplete penetrance of this phenotype.

Talocalcaneal coalition in Muenke syndrome: report of a patient, review of the literature in FGFR-related craniosynostoses, and consideration of mechanism

Muenke syndrome is an autosomal dominant craniosynostosis syndrome resulting from a defining point mutation in the Fibroblast Growth Factor Receptor3 (FGFR3) gene. Muenke syndrome is characterized by coronal craniosynostosis (bilateral more often than unilateral), hearing loss, developmental delay, and carpal and/or tarsal bone coalition. Tarsal coalition is a distinct feature of Muenke syndrome and has been reported since the initial description of the disorder in the 1990s. Although talocalcaneal coalition is the most common tarsal coalition in the general population, it has never previously been reported in a patient with Muenke syndrome. We present a 7-year-old female patient with Muenke syndrome and symptomatic talocalcaneal coalition. She presented at the age of 7 with limping, tenderness and pain in her right foot following a fall and strain of her right foot. She was treated with ibuprofen, shoe inserts, a CAM walker boot, and stretching exercises without much improvement in symptoms. A computed tomography (CT) scan revealed bilateral talocalcaneal coalitions involving the middle facet. She underwent resection of the talocalcaneal coalitions, remaining pain-free post-operatively with an improvement in her range of motion, gait, and mobility. This report expands the phenotype of tarsal coalition in Muenke syndrome to include talocalcaneal coalition. A literature review revealed a high incidence of tarsal coalition in all FGFR related craniosynostosis syndromes when compared to the general population, a difference that is statistically significant. The most common articulation involved in all syndromic craniosynostoses associated with FGFR mutations is the calcaneocuboid articulation.

Epilepsy in Muenke syndrome: FGFR3-related craniosynostosis

Epilepsy, a neurologic disorder characterized by the predisposition to recurrent unprovoked seizures, is reported in more than 300 genetic syndromes. Muenke syndrome is an autosomal-dominant craniosynostosis syndrome characterized by unilateral or bilateral coronal craniosynostosis, hearing loss, intellectual disability, and relatively subtle limb findings such as carpal bone fusion and tarsal bone fusion. Muenke syndrome is caused by a single defining point mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. Epilepsy rarely occurs in individuals with Muenke syndrome, and little detail is reported on types of epilepsy, patient characteristics, and long-term outcomes. We present seven patients with Muenke syndrome and seizures. A review of 789 published cases of Muenke syndrome, with a focus on epilepsy and intracranial anomalies in Muenke syndrome, revealed epilepsy in six patients, with intracranial anomalies in five. The occurrence of epilepsy in Muenke syndrome within our cohort of 58 patients, of whom seven manifested epilepsy, and the intracranial anomalies and epilepsy reported in the literature, suggest that patients with Muenke syndrome may be at risk for epilepsy and intracranial anomalies. Furthermore, the impact of Muenke syndrome on the central nervous system may be greater than previously thought.

Phenotype profile of a genetic mouse model for Muenke syndrome

PURPOSE

The Muenke syndrome mutation (FGFR3 (P250R)), which was discovered 15 years ago, represents the single most common craniosynostosis mutation. Muenke syndrome is characterized by coronal suture synostosis, midface hypoplasia, subtle limb anomalies, and hearing loss. However, the spectrum of clinical presentation continues to expand. To better understand the pathophysiology of the Muenke syndrome, we present collective findings from several recent studies that have characterized a genetically equivalent mouse model for Muenke syndrome (FgfR3 (P244R)) and compare them with human phenotypes.

CONCLUSIONS

FgfR3 (P244R) mutant mice show premature fusion of facial sutures, premaxillary and/or zygomatic sutures, but rarely the coronal suture. The mice also lack the typical limb phenotype. On the other hand, the mutant mice display maxillary retrusion in association with a shortening of the anterior cranial base and a premature closure of intersphenoidal and spheno-occipital synchondroses, resembling human midface hypoplasia. In addition, sensorineural hearing loss is detected in all FgfR3 (P244R) mutant mice as in the majority of Muenke syndrome patients. It is caused by a defect in the mechanism of cell fate determination in the organ of Corti. The mice also express phenotypes that have not been previously described in humans, such as reduced cortical bone thickness, hypoplastic trabecular bone, and defective temporomandibular joint structure. Therefore, the FgfR3 (P244R) mouse provides an excellent opportunity to study disease mechanisms of some classical phenotypes of Muenke syndrome and to test novel therapeutic strategies. The mouse model can also be further explored to discover previously unreported yet potentially significant phenotypes of Muenke syndrome.

Impact of genetics on the diagnosis and clinical management of syndromic craniosynostoses

PURPOSE

More than 60 different mutations have been identified to be causal in syndromic forms of craniosynostosis. The majority of these mutations occur in the fibroblast growth factor receptor 2 gene (FGFR2). The clinical management of syndromic craniosynostosis varies based on the particular causal mutation. Additionally, the diagnosis of a patient with syndromic craniosynostosis is based on the clinical presentation, signs, and symptoms. The understanding of the hallmark features of particular syndromic forms of craniosynostosis leads to efficient diagnosis, management, and long-term prognosis of patients with syndromic craniosynostoses.

METHODS

A comprehensive literature review was done with respect to the major forms of syndromic craniosynostosis and additional less common FGFR-related forms of syndromic craniosynostosis. Additionally, information and data gathered from studies performed in our own investigative lab (lab of Dr. Muenke) were further analyzed and reviewed. A literature review was also performed with regard to the genetic workup and diagnosis of patients with craniosynostosis.

RESULTS

Patients with Apert syndrome (craniosynostosis syndrome due to mutations in FGFR2) are most severely affected in terms of intellectual disability, developmental delay, central nervous system anomalies, and limb anomalies. All patients with FGFR-related syndromic craniosynostosis have some degree of hearing loss that requires thorough initial evaluations and subsequent follow-up.

CONCLUSIONS

Patients with syndromic craniosynostosis require management and treatment of issues involving multiple organ systems which span beyond craniosynostosis. Thus, effective care of these patients requires a multidisciplinary approach.

De novo deletion of chromosome 20q13.33 in a patient with tracheo-esophageal fistula, cardiac defects and genitourinary anomalies implicates GTPBP5 as a candidate gene

BACKGROUND

CASE REPORT

CONCLUSIONS

Analysis of FOXF1 and the FOX gene cluster in patients with VACTERL association

VACTERL association, a relatively common condition with an incidence of approximately 1 in 20,000 -35,000 births, is a non-random association of birth defects that includes vertebral defects (V), anal atresia (A), cardiac defects (C), tracheo-esophageal fistula (TE), renal anomalies (R) and limb malformations (L). Although the etiology is unknown in the majority of patients, there is evidence that it is causally heterogeneous. Several studies have shown evidence for inheritance in VACTERL, implying a role for genetic loci. Recently, patients with component features of VACTERL and a lethal developmental pulmonary disorder, alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV), were found to harbor deletions or mutations affecting FOXF1 and the FOX gene cluster on chromosome 16q24. We investigated this gene through direct sequencing and high-density SNP microarray in 12 patients with VACTERL association but without ACD/MPV. Our mutational analysis of FOXF1 showed normal sequences and no genomic imbalances affecting the FOX gene cluster on chromosome 16q24 in the studied patients. Possible explanations for these results include the etiologic and clinical heterogeneity of VACTERL association, the possibility that mutations affecting this gene may occur only in more severely affected individuals, and insufficient study sample size.

Multiple bromodomain genes are involved in restricting the spread of heterochromatic silencing at the Saccharomyces cerevisiae HMR-tRNA boundary

The transfer RNA gene downstream from the HMR locus in S. cerevisiae functions as part of a boundary (barrier) element that restricts the spread of heterochromatic gene silencing into the downstream region of chromosome III. A genetic screen for identifying additional genes that, when mutated, allow inappropriate spreading of silencing from HMR through the tRNA gene was performed. YTA7, a gene containing bromodomain and ATPase homologies, was identified multiple times. Previously, others had shown that the bromodomain protein Bdf1p functions to restrict silencing at yeast euchromatin-heterochromatin boundaries; therefore we deleted nonessential bromodomain-containing genes to test their effects on heterochromatin spreading. Deletion of RSC2, coding for a component of the RSC chromatin-remodeling complex, resulted in a significant spread of silencing at HMR. Since the bromodomain of YTA7 lacks a key tyrosine residue shown to be important for acetyllysine binding in other bromodomains, we confirmed that a GST-Yta7p bromodomain fusion was capable of binding to histones in vitro. Epistasis analysis suggests that YTA7 and the HMR-tRNA function independently to restrict the spread of silencing, while RSC2 may function through the tRNA element. Our results suggest that multiple bromodomain proteins are involved in restricting the propagation of heterochromatin at HMR.