FZD6 encoding the Wnt receptor frizzled 6 is mutated in autosomal-recessive nail dysplasia

BACKGROUND

Isolated nail dysplasia is rare and has been reported in only a small number of families.

OBJECTIVES

To describe and characterize two Pakistani families with an autosomal-recessive inherited nail dysplasia.

METHODS

Genome-wide linkage analysis; mutation screening of candidate genes by Sanger sequencing; cloning of FZD6 and protein analyses; immunohistochemistry.

RESULTS

We mapped this genodermatosis to chromosome 8q22.3, and identified a homozygous nonsense mutation c.1750G>T (p.E584X) in the frizzled 6 (FZD6) gene in all affected individuals. Immunohistochemical analyses in nail sections from healthy individuals revealed strong expression of FZD6 in the ventral nail matrix and a less pronounced expression of FZD6 in the nail bed.

CONCLUSIONS

FZD6 belongs to a family of proteins that serve as receptors in Wnt signalling pathways, and has been shown to act as a negative regulator of the canonical Wnt/β-catenin signalling cascade and a positive regulator of the noncanonical Wnt or planar cell polarity pathway. The present results therefore suggest that FZD6 plays a pivotal role in the growth and guidance of the nail plate in humans by acting as a molecular switch between different Wnt pathways. Previous studies have identified mutations in the RSPO4 and LMX1B components of the Wnt pathway in patients with the hypoplastic nail disorders anonychia and nail-patella syndrome, respectively. Only recently, FZD6 mutations were identified in isolated nail dysplasia. The present results emphasize the important role of the Wnt pathways in nail development and increase understanding of Wnt-mediated developmental events in general.

The utility of cytodiagnostic urinalysis as a tool to diagnose kidney allograft dysfunction in the era lymphocyte-depleting induction therapy

Cytodiagnostic urinalysis (CDU) has been used to evaluate causes of kidney allograft dysfunction, such as an acute rejection episode (ARE), calcineurin inhibitor (CNI) toxicity, or polyoma virus infection. We examined the concordance between CDU and allograft biopsy in patients with allograft dysfunction. Between 2002 and 2006, 201 patients had CDU performed within 7 days of a biopsy. The cohort was black (73%) with, male preponderance (59.2%), and an overall mean age of 48±13 years with 46% having received a deceased donor kidney. The induction regimen consisted of either antithymocyte globulin or alemtuzumab. CDU results that demonstrated 5 to 10 lymphocytes per high-power field (HPF) and >20 lymphocytes/HPF had 2.5 increased odds of predicting acute rejection (AR) on biopsy (odds ratio [OR] 2.5; 95% confidence interval [CI] 1.12-5.79; P=.025). In the era of antithymocyte globulin induction, a CDU result demonstrating>5 lymphocytes/HPF had a 4.3 increased odds of predicting AR (CI 1.76-10.50; P=.001). This association was lost with alemtuzumab induction. A positive CDU result for calcineurin inhibitor (CNI) toxicity did not predict CNI nephrotoxcity on biopsy, but a positive CDU for polyoma virus infection predicted polyoma virus nephropathy (OR 22.18; CI: 4.41-111.63; P<.001). In conclusion, CDU is an adjunctive diagnostic tool for kidney transplantation.

Combined pedunculopontine-subthalamic stimulation in Parkinson disease

OBJECTIVE

To assess the effect of deep brain stimulation (DBS) in the pedunculopontine nucleus (PPN) and caudal zona incerta (cZi)-both separately and in combination-on motor symptoms and regional cerebral blood flow (rCBF) in patients with Parkinson disease (PD).

METHODS

Four patients with bilateral cZi and PPN DBS electrodes were rated with the Unified Parkinson's Disease Rating Scale motor subscale (UPDRS-III) when taking and withdrawn from medication. A block of 16 [(15)O]-H(2)O PET resting measurements of rCBF were performed in 4 different states with patients withdrawn from medication: 1) no stimulation, 2) cZi stimulation alone, 3) PPN stimulation alone, 4) combined PPN/cZi stimulation.

RESULTS

When patients were medicated, combined PPN/cZi stimulation produced a statistically significant improvement in UPDRS-III score compared to cZi stimulation alone. In the "off" medication state, the clinical effect of combined stimulation was not significantly different from that induced by cZi stimulation alone. Concomitant PPN/cZi stimulation had a cumulative effect on levels of rCBF, effectively combining subcortical and cortical changes induced by stimulation of either target in isolation.

CONCLUSIONS

These findings suggest that concomitant low frequency stimulation of PPN and cZi regions induces additive brain activation changes and provides improved control of PD symptoms when medicated.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that concomitant low frequency stimulation of PPN and cZI improves motor symptoms in patients with PD on dopamine replacement. It provides Class III evidence that concomitant low frequency stimulation of PPN and cZi induces additive rCBF changes in motor areas of brain.

Nutritional evaluation of distillery sludge and its effect as a substitute of canola meal on performance of broiler chickens

The study was conducted to investigate the chemical composition of distillery yeast sludge and its inclusion in broiler diets to replace canola meal. Raw distillery yeast sludge was washed with water using water and sludge in the ratio 6:1, respectively. Proximate analysis of raw distillery yeast sludge and washed distillery sludge was carried out for crude protein (CP), true protein (TP), ether extract (EE), ash, acid insoluble ash and nitrogen free extract (NFE) determination. Mineral contents and amino acid profile of raw distillery yeast sludge and washed distillery sludge were also determined. After chemical evaluation, four iso-caloric and iso-nitrogenous broiler starter and finisher diets were prepared in mash form using 0 (control), 4, 8 and 12% levels of washed distillery sludge replacing canola meal. One hundred and twenty day-old broiler chicks were randomly distributed into 12 experimental units in such a way that each diet was offered to three experimental units, each comprising of 10 chicks. It was observed that washing affected the nutrients either by decreasing or increasing their concentration. It decreased the total mineral contents whereas CP, TP, EE and NFE contents increased. Washing also increased amino acid profile. Average feed intake and weight gain were higher in birds fed diet containing 8% washed distillery sludge and lower in birds fed diet containing 0% washed distillery sludge. Feed cost per kg live weight gain decreased significantly as the level of washed distillery sludge was increased in the diet. Average heart, liver and pancreas weights decreased with increased level of washed distillery sludge in the diet. The study revealed that after washing, distillery yeast sludge can be used successfully in broiler diets up to the level of 8% without any adverse effect on broiler’s performance.

Assessing the problem of counterfeit medications in the United Kingdom

Counterfeit medicines pose an ever-increasing threat to public health, although precise tracking of illegal counterfeit prescription drug activity is difficult. Available data indicate that all types of medications have been targeted. Adverse health effects, including death, have resulted from using counterfeit medications; consumers who self-medicate without appropriate interactions with the healthcare system rarely receive adequate healthcare. The Internet provides a large, convenient route for counterfeiters to reach potential buyers with unregulated, often dangerous, products. The majority of medicines purchased via unverified Internet sites are counterfeit; often, these products lack the purported drug compound or have variable concentrations of active ingredients and sometimes contain dangerous toxins. Although many consumers acknowledge some degree of risk with purchasing medications via the Internet, speed, convenience and cost often prompt these purchases. Counterfeit medications also have been detected in the legitimate supply chain, but represent a significantly smaller proportion of sales than those purchased via the Internet. Pilot programmes in Europe have demonstrated that product verification systems prevent penetration of counterfeit products into the legitimate supply chain. Significant EU legislation, including stronger penalties for counterfeiting, is in development. In the United Kingdom, the Medicines and Healthcare Products Regulatory Agency (MHRA) launched an initiative against counterfeit medication. Healthcare professionals should report suspected cases of counterfeit medication to the MHRA, be alert to threats to the medicine supply, and provide practical advice to patients about ordering medications online, including avoiding unregulated Internet pharmacies, and being suspicious of sites offering substantial discounts and prescription-only medication without a prescription.

Measurement of forces applied during Macintosh direct laryngoscopy compared with GlideScope® videolaryngoscopy

Laryngoscopy can induce stress responses that may be harmful in susceptible patients. We directly measured the force applied to the base of the tongue as a surrogate for the stress response. Force measurements were obtained using three FlexiForce Sensors(®) (Tekscan Inc, Boston, MA, USA) attached along the concave surface of each laryngoscope blade. Twenty-four 24 adult patients of ASA physical status 1-2 were studied. After induction of anaesthesia and neuromuscular blockade, laryngoscopy and tracheal intubation was performed using either a Macintosh or a GlideScope(®) (Verathon, Bothell, WA, USA) laryngoscope. Complete data were available for 23 patients. Compared with the Macintosh, we observed lower median (IQR [range]) peak force (9 (5-13 [3-25]) N vs 20 (14-28 [4-41]) N; p = 0.0001), average force (5 (3-7 [2-19]) N vs 11 (6-16 [1-24]) N; p = 0.0003) and impulse force (98 (42-151 [26-444]) Ns vs 150 (93-207 [17-509]) Ns; p = 0.017) with the GlideScope. Our study shows that the peak lifting force on the base of the tongue during laryngoscopy is less with the GlideScope videolaryngoscope compared with the Macintosh laryngoscope.

IL-7Rα deficiency in p53null mice exacerbates thymocyte telomere erosion and lymphomagenesis

Interleukin-7 (IL-7) is an essential T-cell survival cytokine. IL-7 receptor (IL-7Rα) deficiency severely impairs T-cell development due to substantial apoptosis. We hypothesized that IL-7Rα(null)-induced apoptosis is partially contributed by an elevated p53 activity. To investigate the genetic association of IL-7/IL-7Rα signaling with the p53 pathway, we generated IL-7Rα(null)p53(null) (DKO) mice. DKO mice exhibited a marked reduction of apoptosis in developing T cells and an augmented thymic lymphomagenesis with telomere erosions and exacerbated chromosomal anomalies, including chromosome duplications, breaks, and translocations. In particular, Robertsonian translocations, in which telocentric chromosomes fuse at the centromeric region, and a complete loss of telomeres at the fusion site occurred frequently in DKO thymic lymphomas. Cellular and molecular investigations revealed that IL-7/IL-7Rα signaling withdrawal diminished the protein synthesis of protection of telomere 1 (POT1), a subunit of telomere protective complex shelterin, leading to telomere erosion and the activation of the p53 pathway. Blockade of IL-7/IL-7Rα signaling in IL-7-dependent p53(null) cells reduced POT1 expression and caused telomere and chromosome abnormalities similar to those observed in DKO lymphomas. This study underscores a novel function of IL-7/IL-7Rα during T-cell development in regulating telomere integrity via POT1 expression and provides new insights into cytokine-mediated survival signals and T-cell lymphomagenesis.

Improved control of severe hypoglycemia in patients with malignant insulinomas by peptide receptor radionuclide therapy

CONTEXT

Insulinomas are relatively rare neuroendocrine tumors of the pancreas. Only 10% are considered malignant. Control of insulin hypersecretion and hypoglycemia in patients with malignant insulinomas may be extremely difficult. Different medications and chemotherapy schedules have been used.

PATIENTS

Five patients with metastatic insulinomas and severe, poorly controllable, hypoglycemia are described. These patients required continuous glucose infusion to control severe hypoglycemia, which were induced by the high levels of insulin secretion. Conventional medications, such as diazoxide, or streptozotocin-based chemotherapies had been used to control hypoglycemia but were ineffective and/or produced adverse effects. All patients were treated with sc octreotide.

INTERVENTION

Peptide receptor radionuclide therapy with radiolabeled-somatostatin analogs was used.

RESULTS

After the start of radiolabeled somatostatin analog therapy, the five patients with metastatic insulinomas had stable disease for a mean period of 27 months. During these months, the patients were without any hypoglycemic episodes. Finally, three of five patients died because of progressive disease.

CONCLUSIONS

Radiolabeled somatostatin analog therapy can stabilize tumor growth and can be very successful in further controlling severe hypoglycemia in malignant insulinomas. In our series, this eventually resulted in improved survival outside the hospital setting.