A Homozygous PDE6D Mutation in Joubert Syndrome Impairs Targeting of Farnesylated INPP5E Protein to the Primary Cilium

Joubert syndrome (JS) is characterized by a distinctive cerebellar structural defect, namely the « molar tooth sign ». JS is genetically heterogeneous, involving 20 genes identified to date, which are all required for cilia biogenesis and/or function. In a consanguineous family with JS associated with optic nerve coloboma, kidney hypoplasia, and polydactyly, combined exome sequencing and mapping identified a homozygous splice‐site mutation in PDE6D, encoding a prenyl‐binding protein. We found that pde6d depletion in zebrafish leads to renal and retinal developmental anomalies and wild‐type but not mutant PDE6D is able to rescue this phenotype. Proteomic analysis identified INPP5E, whose mutations also lead to JS or mental retardation, obesity, congenital retinal dystrophy, and micropenis syndromes, as novel prenyl‐dependent cargo of PDE6D. Mutant PDE6D shows reduced binding to INPP5E, which fails to localize to primary cilia in patient fibroblasts and tissues. Furthermore, mutant PDE6D is unable to bind to GTP‐bound ARL3, which acts as a cargo‐release factor for PDE6D‐bound INPP5E. Altogether, these results indicate that PDE6D is required for INPP5E ciliary targeting and suggest a broader role for PDE6D in targeting other prenylated proteins to the cilia. This study identifies PDE6D as a novel JS disease gene and provides the first evidence of prenyl‐binding‐dependent trafficking in ciliopathies.     

Prevalence of lymph nodes in the parametrium of radical vaginal trachelectomy (RVT) specimen

Objective

In order to evaluate radicality in fertility preserving surgery in women with early invasive cervical cancer we analyzed the parametrium of specimens of patients treated by radical vaginal trachelectomy for the presence of lymph nodes. We tried to identify morphologic factors associated with the presence of parametrial lymph nodes.

Methods

We analyzed surgical specimens of 112 patients who underwent radical trachelectomy between June 2004 and April 2009 at the Department of Gynecologic Oncology at Charité Campus Benjamin Franklin and Campus Mitte. All parametrial tissue was step sectioned and a total of 1878H&;E stained histological sections were analyzed.

Results

In 8 patients (7.1%) a total of 13 lymph nodes were detected. Five lymph nodes in four patients had been primarily detected by routine histological examination. In one of these patients (0.9%) a 2 mm lymph node metastasis was found. Serial sectioning revealed additional seven lymph nodes in four patients. The thickness of parametrium correlated significantly with the presence of lymph nodes in the parametrium.

Conclusion

The presence of small lymph nodes in the parametrium of specimens of radical trachelectomy is low. In patients with early-stage cervical cancer, the incidence of metastasis is less than 1%. Preoperative assessment of the volume of the parametrium may indicate which patients need parametrial resection.     

Feasibility of elementary school children’s use of hand gel and facemasks during influenza season

Please cite this paper as: Allison et al. (2010) Feasibility of elementary school children’s use of hand gel and facemasks during influenza season. Influenza and Other Respiratory Viruses 4(4), 223–229. Background The feasibility of non-pharmacologic interventions to prevent influenza’s spread in schools is not well known. Objectives To determine the acceptability of, adherence with, and barriers to the use of hand gel and facemasks in elementary schools. Patients and Methods Intervention: We provided hand gel and facemasks to 20 teachers and their students over 4 weeks. Gel use was promoted for the first 2 weeks; mask use was promoted for the second 2 weeks. Outcomes: Acceptability, adherence, and barriers were measured by teachers’ responses on weekly surveys. Mask use was also measured by observation. Results The weekly survey response rate ranged from 70% to 100%. Averaged over 2 weeks, 89% of teachers thought gel use was not disruptive (week 1 – 17/20, week 2 – 16/17), 95% would use gel next winter (week 1 – 19/20, week 2 – 16/17), and 97% would use gel in a pandemic (week 1 – 20/20, week 2 – 16/17). Averaged over 2 weeks, 39% thought mask use was not disruptive (week 1 – 6/17, week 2 – 6/14), 35% would use masks next winter (week 1 – 5/17, week 2 – 6/14), and 97% would use masks in a pandemic (week 1 – 16/17, week 2 – 14/14). About 70% estimated that their students used hand gel ≥4×/day for both weeks (week 1 – 14/20, week 2 – 13/17). Students’ mask use declined over time with 59% of teachers (10/17) estimating regular mask use during week 1 and 29% (4/14) during week 2. By observation, 30% of students wore masks in week 1, while 15% wore masks in week 2. Few barriers to gel use were identified; barriers to mask use were difficulty reading facial expressions and physical discomfort. Conclusions Hand gel use is a feasible strategy in elementary schools. Acceptability and adherence with facemasks was low, but some students and teachers did use facemasks for 2 weeks, and most teachers would use masks in their classroom in a pandemic.     

Very preterm birth is a risk factor for increased systolic blood pressure at a young adult age

Children born very prematurely who show intrauterine growth retardation (IUGR) are suggested to be at risk of developing high blood pressure as adults. Renal function may already be impaired by young adult age. To study whether very preterm birth affects blood pressure in young adults, we measured 24-h ambulatory blood pressure (Spacelabs™ 90207 device) and renin concentration in 50 very premature individuals (<32 weeks of gestation), either small (SGA) or appropriate (AGA) for gestational age (21 SGA, 29 AGA), and 30 full-term controls who all were aged 20 years at time of measurement. The mean (standard deviation) daytime systolic blood pressure in SGA and AGA prematurely born individuals, respectively, was 122.7 (8.7) and 123.1 (8.5) mmHg. These values were, respectively, 3.6 mmHg [95% confidence interval (CI) −0.9 to 8.0] and 4.2 mmHg (95% CI 0.4−8.0) higher than in controls [119.6 (7.6)]. Daytime diastolic blood pressure and nighttime blood pressure did not differ between groups. We conclude that individuals born very preterm have higher daytime systolic blood pressure and higher risk of hypertension at a young adult age.     

DNA fingerprinting of sister blastomeres from human IVF embryos

BACKGROUND: Previously published single cell DNA fingerprinting systems have been plagued by high rates of allele drop-out (ADO) and preferential amplification (PA) preventing clinical application in preimplantation genetic diagnosis. METHODS: Tetranucleotide microsatellite markers with high heterozygosity, known allelic size ranges and minimal PCR stutter artefacts were selected for chromosomes X, 13, 18 and 21 and optimized in a multiplex fluorescent (FL)-PCR format. FL-PCR products were analysed using the ABI Prism 377 DNA sequenator and Genescan software. Validation of the DNA fingerprinting system was performed on single diploid (n = 50) and aneuploid (n = 25) buccal cells and embryonic blastomeres (n = 21). RESULTS: The optimized pentaplex PCR DNA fingerprinting system displayed a high proportion of successful amplifications (>91%) and low ADO and PA (<6%) when assessed on 50 human buccal cells. DNA fingerprints of single cells from a subject with Down's syndrome detected the expected tri-allelic pattern for the chromosome 21 marker, confirming trisomy 21. In a blind study on 21 single blastomeres, all embryos were identifiable by their unique DNA fingerprints and shared parental alleles. CONCLUSIONS: A highly specific multiplex FL-PCR based on the amplification of five highly polymorphic microsatellite markers was developed for single cells. This finding paves the way for the development of a more complex PCR DNA fingerprinting system to assess aneuploidy and single gene mutations in IVF embryos from couples at genetic risk.     

CD97, but not its closely related EGF-TM7 family member EMR2, is expressed on gastric,pancreatic, and esophageal carcinomas

CD97 expression is related closely to the dedifferentiation and tumor stage in thyroid carcinomas. We systematically examined the role of CD97 and its closest relative, EMR2, in normal and malignant gastric, esophageal, and pancreatic tissue. The normal tissues were EMR2-, whereas CD97 was expressed slightly in the parietal cells of gastric mucosa and in exocrine pancreatic cells. Interestingly, intralobular and interlobular pancreatic ducts were CD97+. All tumors were EMR2-. CD97 was expressed by 44 of 50 gastric, 14 of 18 pancreatic, and 10 of 13 esophageal carcinomas. Of the 44 gastric cancers, 27 showed disseminated or scattered tumor cells at the invasion front with stronger CD97 expression than tumor cells located in solid tumor formations. There was no correlation between CD97 levels in the tumors or soluble CD97 in the serum samples and the clinicopathologic features of the patients. Taken together, significant numbers of gastric, esophageal, and pancreatic carcinomas are CD97+, whereas its homolog, EMR2, does not have any role in such tumors.