A novel candidate gene in autosomal dominant facial pruritus.

In the clinical investigation of a family with debilitating centrofacial pruritus by exome sequencing, we have observed a clear segregation of the TRPM3 variant outlined, which is highly suggestive of a causal relationship.

Detailed characterization of MLH1 p.D41H and p.N710D variants coexisting in a Lynch syndrome family with conserved MLH1 expression tumors.

Lynch syndrome (LS) is an autosomal dominant cancer-susceptibility disease caused by inactivating germline mutations in mismatch repair (MMR) genes. Variants of unknown significance (VUS) are often detected in mutational analysis of MMR genes. Here we describe a large family fulfilling Amsterdam I criteria carrying two rare VUS in the MLH1 gene: c.121G > C (p.D41H) and c.2128A > G (p.N710D). Collection of clinico-pathological data, multifactorial analysis, in silico predictions, and functional analyses were used to elucidate the clinical significance of the identified MLH1 VUS. Only the c.121G > C variant cosegregated with LS-associated tumors in the family. Diagnosed colorectal tumors were microsatellite unstable although immunohistochemical staining revealed no loss of MMR proteins expression. Multifactorial likelihood analysis classified c.2128A > G as a non-pathogenic variant and c.121G > C as pathogenic. In vitro functional tests revealed impaired MMR activity and diminished expression of c.121G > C. Accordingly, the N710 residue is located in the unconserved MLH1 C-terminal domain, whereas D41 is highly conserved and located in the ATPase domain. The obtained results will enable adequate genetic counseling of c.121G > C and c.2128A > G variant carriers and their families. Furthermore, they exemplify how cumulative data and comprehensive analyses are mandatory to refine the classification of MMR variants.

A review of mismatch repair gene transcripts: issues for interpretation of mRNA splicing assays.

Many mismatch repair (MMR) gene disease-causing mutations identified in cancer patients result in aberrant messenger RNA (mRNA) splicing. However, mRNA assay interpretation can be complicated by the existence of naturally occurring alternative mRNA transcripts, most of which have not been formally described or fully characterized. Here, we provide a comprehensive catalogue of all MMR transcripts described to date, and a review of MMR nucleotide variants associated with an apparent upregulation of alternatively spliced transcripts. This work sets reference starting points for designing and interpreting MMR RNA analyses. Our database and literature searches retrieved 30 MLH1, 22 MSH2, 4 MSH6 and 9 PMS2 alternative transcripts, many predicted to introduce premature termination codons. Furthermore, we collected information on 66 MLH1, 24 MSH2 and 6 PMS2 nucleotide variants reported to be associated with altered expression of at least one of these alternative transcripts, and in many instances reported as splicing mutations. This review shows that there are many alternatively spliced MMR transcripts, which have potential to confound interpretation of splicing assays. These findings highlight the need to perform RNA analysis of patients systematically in parallel with control individuals, and call for the implementation of quantitative assessment of transcript levels for informed interpretation of mRNA assays.

Deletion of MAP2K2/MEK2: a novel mechanism for a RASopathy?

RASopathies are a class of genetic syndromes caused by germline mutations in genes encoding Ras/mitogen-activated protein kinase (Ras/MAPK) pathway components. Cardio-facio-cutaneous (CFC) syndrome is a RASopathy characterized by distinctive craniofacial features, skin and hair abnormalities, and congenital heart defects caused by activating mutations of BRAF, MEK1, MEK2, and KRAS. We define the phenotype of seven patients with de novo deletions of chromosome 19p13.3 including MEK2; they present with a distinct phenotype but have overlapping features with CFC syndrome. Phenotypic features of all seven patients include tall forehead, thick nasal tip, underdeveloped cheekbones, long midface, sinuous upper vermilion border, tall chin, angular jaw, and facial asymmetry. Patients also have developmental delay, hypotonia, heart abnormalities, failure to thrive, obstructive sleep apnea, gastroesophageal reflux and integument abnormalities. Analysis of epidermal growth factor-stimulated fibroblasts revealed that P-MEK1/2 was ∼50% less abundant in cells carrying the MEK2 deletion compared to the control. Significant differences in total MEK2 and Sprouty1 abundance were also observed. Our cohort of seven individuals with MEK2 deletions has overlapping features associated with RASopathies. This is the first report suggesting that, in addition to activating mutations, MEK2 haploinsufficiency can lead to dysregulation of the MAPK pathway.

Standard oxygen consumption of seasonally acclimatized cownose rays, Rhinoptera bonasus (Mitchill 1815), in the northern Gulf of Mexico.

Standard oxygen consumption rate (MO(2)) was determined for 19 cownose rays (Rhinoptera bonasus) using flow-through respirometry. Rays ranged in size from 0.4 to 8.25 kg (350-790 mm DW). Respirometry experiments were conducted on seasonally acclimatized rays at temperatures from 19.0 to 28.8 degrees C. Estimates of mass-dependent MO(2) ranged from 55.88 mg O(2) kg(-1) h(-1) for an 8.25 kg ray to 332.75 mg O(2) kg(-1) h(-1) for a 2.2 kg animal at 22-25 degrees C. Multiple regression analysis examining the effect of temperature, salinity, and mass on standard mass-independent MO(2) found temperature (P < 0.01), and mass (P < 0.0001) to have a significant effect on oxygen consumption, whereas salinity did not (P > 0.05). Q (10) was calculated as 2.33 (19-28 degrees C), falling between the estimates determined for two other batoid species, the bull ray (Myliobatos aquila; Q (10) = 1.87) and the bat ray (Myliobatis californica; Q (10) = 3.00). The difference in the Q (10) estimates may be attributed to the use of seasonally acclimatized as opposed to laboratory-acclimated animals.

Treatment approaches to bruxism.

Bruxism, or the grinding and clenching of teeth, occurs in approximately 15 percent of children and in as many as 96 percent of adults. The etiology of bruxism is unclear, but the condition has been associated with stress, occlusal disorders, allergies and sleep positioning. Because of its nonspecific pathology, bruxism may be difficult to diagnose. In addition to complaints from sleep partners, signs of teeth grinding include masticatory pain or fatigue, headaches, tooth sensitivity and attrition, oral infection and temporomandibular joint disorders. Signs of bruxism include tooth wear and mobility, as well as tender or hypertrophied masticatory muscles and joints. Children with bruxism are usually managed with observation and reassurance. Adults may be managed with stress reduction therapy, alteration of sleep positioning, drug therapy, biofeedback training, physical therapy and dental evaluation. If significant tooth attrition, mobility or fracture occurs, dental referral is mandatory.

How to break down tasks so they don't break you: coping with overwhelming demands on your time.

Everyone, in every profession, seems to have too much to do and too little time to do it all. This seems to be even more true in the health care setting, where change is constant. Health care supervisors can become so overwhelmed with tasks that are expected of them that they have no idea of where to even begin. Rather than thinking about everything that must be done, the one single task strategy describes how you can break down your overwhelming tasks into manageable steps.

Interaction of nucleolar phosphoprotein C23 with cloned segments of rat ribosomal deoxyribonucleic acid.

Protein C23, a predominant nucleolar phosphoprotein and a putative nucleolus organizer protein, was analyzed for its general DNA binding characteristics and for its selectivity in binding plasmid DNAs containing cloned fragments of the genes that code for ribosomal RNA (rDNA). By use of nitrocellulose filter disk assays, the protein bound saturably to nuclear DNA with a relatively high affinity. Binding was maximal at low ionic strength (0-0.1 M KCl) with progressively decreasing binding at or above 0.2 M. In competition assays protein C23 showed a marked preference for linear single-stranded vs. double-stranded DNA and little or no affinity for ribosomal RNA. The relative affinities of rDNA sequences for protein C23 were determined with cloned fragments spanning 15.8 kilobases (kb) of DNA starting approximately 3.7 kb upstream from the initiation site for 45S preribosomal RNA to near the 3' end of the sequence coding for 28S RNA. Of the five linearized plasmids tested, only one (pKW1) was an effective competitor for 32P-labeled nuclear DNA. As measured by the concentration of competing DNA required to achieve 50% competition, pKW1 was approximately 20-fold more effective than the second best competitor. The DNA insert in pKW1 is a 3.5-kb sequence which is located in the nontranscribed spacer region less than 0.5 kb upstream from the initiation site for 45S preribosomal RNA. These results suggest that protein C23 has a preference for binding DNA sequences in the nontranscribed spacer of rDNA.