Semin Hear 2017; 38: 223-224
DOI: 10.1055/s-0037-1603690
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
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Semin Hear 2017; 38: 225-262
DOI: 10.1055/s-0037-1603726
Noise levels are truly continuous in relatively few occupations, with some degree of intermittency the most common condition. The sound levels of intermittent noise are often referred to as non-Gaussian in that they are not normally distributed in the time domain. In some conditions, intermittent noise affects the ear differently from continuous noise, and it is this assumption that underlies the selection of the 5-dB exchange rate (ER). The scientific and professional communities have debated this assumption over recent decades. This monograph explores the effect of non-Gaussian noise on the auditory system. It begins by summarizing an earlier report by the same author concentrating on the subject of the ER. The conclusions of the earlier report supported the more conservative 3-dB ER with possible adjustments to the permissible exposure limit for certain working conditions. The current document has expanded on the earlier report in light of the relevant research accomplished in the intervening decades. Although some of the animal research has supported the mitigating effect of intermittency, a closer look at many of these studies reveals certain weaknesses, along with the fact that these noise exposures were not usually representative of the conditions under which people actually work. The more recent animal research on complex noise shows that intermittencies do not protect the cochlea and that many of the previous assumptions about the ameliorative effect of intermittencies are no longer valid, lending further support to the 3-dB ER. The neurologic effects of noise on hearing have gained increasing attention in recent years because of improvements in microscopy and immunostaining techniques. Animal experiments showing damage to auditory synapses from noise exposures previously considered harmless may signify the need for a more conservative approach to the assessment of noise-induced hearing loss and consequently the practice of hearing conservation programs.
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Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
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Semin Hear 2017; 38: C1-C10
DOI: 10.1055/s-0037-1603759
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA
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Population rCharacteristics and Progressive Disability in Neuofibromatosis Type 2.
World Neurosurg. 2017 Jul 15;:
Authors: Iwatate K, Yokoo T, Iwatate E, Ichikawa M, Sato T, Fujii M, Sakuma J, Saito K
Abstract
OBJECTIVE: To characterize the clinical features of the NF2 population and determine prognostic risk factors for progressive disabilities.
METHODS: In this retrospective cohort study of the Japanese national NF2 registry between 2009-2013, various clinical data (demographic, history, oncological, and neurological) of 807 patients with diagnosis of NF2 were analyzed. The overall severity of neurological disability was assessed using a comprehensive 25-point scoring system encompassing a wide variety of neurological deficits. In 587 patients in whom longitudinal disability data were available, multivariate logistic regression was performed to identify risk factors of significant disability progression.
RESULTS: The clinical characteristics of the Japanese NF2 population were heterogeneous Median onset age [range] of 24 years [1-80]; male-to-female ratio 1:1.29; initial severity score 4 [0-22] out of 25-points. Family history was present in 33%. Most frequent clinical features were bilateral cranial nerve VIII nerve sheath tumor (CN8 NST, 87%), spinal NST (80%), hearing loss (65%), spinal dysfunction (50%), intracranial meningioma (49%), and facial paresis (36%). Disability score progressed by ≥5-points in 6.1% of patients over the study period. Based on multivariate logistic regression analyses, the significant independent risk factors of progression (p-value) included: onset age <25 years (p=0.015), positive family history (p=0.007), positive treatment history (p=0.026) hearing loss (p=0.014), facial paresis (p=0.015), blindness (p=0.011), hemiparesis (p=0.025).
CONCLUSIONS: The NF2 population in Japan is heterogeneous in clinical features. Risk factors of progressive disability include younger age of onset, positive family history, positive treatment history, and specific neurological deficits.
PMID: 28720529 [PubMed - as supplied by publisher]
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Autosomal Recessive Keratoderma-Ichthyosis-Deafness (ARKID) Syndrome Is Caused by VPS33B Mutations Affecting Rab Protein Interaction and Collagen Modification.
J Invest Dermatol. 2017 Apr;137(4):845-854
Authors: Gruber R, Rogerson C, Windpassinger C, Banushi B, Straatman-Iwanowska A, Hanley J, Forneris F, Strohal R, Ulz P, Crumrine D, Menon GK, Blunder S, Schmuth M, Müller T, Smith H, Mills K, Kroisel P, Janecke AR, Gissen P
Abstract
In this paper, we report three patients with severe palmoplantar keratoderma associated with ichthyosis and sensorineural deafness. Biallelic mutations were found in VPS33B, encoding VPS33B, a Sec1/Munc18 family protein that interacts with Rab11a and Rab25 proteins and is involved in trafficking of the collagen-modifying enzyme LH3. Two patients were homozygous for the missense variant p.Gly131Glu, whereas one patient was compound heterozygous for p.Gly131Glu and the splice site mutation c.240-1G>C, previously reported in patients with arthrogryposis renal dysfunction and cholestasis syndrome. We demonstrated the pathogenicity of variant p.Gly131Glu by assessing the interactions of the mutant VPS33B construct and its ability to traffic LH3. Compared with wild-type VPS33B, the p.Gly131Glu mutant VPS33B had reduced coimmunoprecipitation and colocalization with Rab11a and Rab25 and did not rescue LH3 trafficking. Confirming the cell-based experiments, we found deficient LH3-specific collagen lysine modifications in patients' urine and skin fibroblasts. Additionally, the epidermal ultrastructure of the p.Gly131Glu patients mirrored defects in tamoxifen-inducible VPS33B-deficient Vps33b(fl/fl)-ER(T2) mice. Both patients and murine models revealed an impaired epidermal structure, ascribed to aberrant secretion of lamellar bodies, which are essential for epidermal barrier formation. Our results demonstrate that p.Gly131Glu mutant VPS33B causes an autosomal recessive keratoderma-ichthyosis-deafness syndrome.
PMID: 28017832 [PubMed - indexed for MEDLINE]
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Challenges of Treating Childhood Medulloblastoma in a Country With Limited Resources: 20 Years of Experience at a Single Tertiary Center in Malaysia.
J Glob Oncol. 2017 Apr;3(2):143-156
Authors: Rajagopal R, Abd-Ghafar S, Ganesan D, Bustam Mainudin AZ, Wong KT, Ramli N, Jawin V, Lum SH, Yap TY, Bouffet E, Qaddoumi I, Krishnan S, Ariffin H, Abdullah WA
Abstract
PURPOSE: Pediatric medulloblastoma (MB) treatment has evolved over the past few decades; however, treating children in countries with limited resources remains challenging. Until now, the literature regarding childhood MB in Malaysia has been nonexistent. Our objectives were to review the demographics and outcome of pediatric MB treated at the University Malaya Medical Center between January 1994 and December 2013 and describe the challenges encountered.
METHODS: Fifty-one patients with childhood MB were seen at University Malaya Medical Center. Data from 43 patients were analyzed; eight patients were excluded because their families refused treatment after surgery.
RESULTS: Headache and vomiting were the most common presenting symptoms, and the mean interval between symptom onset and diagnosis was 4 weeks. Fourteen patients presented with metastatic disease. Five-year progression-free survival (± SE) for patients ≥ 3 years old was 41.7% ± 14.2% (95% CI, 21.3% to 81.4%) in the high-risk group and 68.6% ± 18.6% (95% CI, 40.3% to 100%) in the average-risk group, and 5-year overall survival (± SE) in these two groups was 41.7% ± 14.2% (95% CI, 21.3% to 81.4%) and 58.3% ± 18.6% (95% CI, 31.3% to 100%), respectively. Children younger than 3 years old had 5-year progression-free and overall survival rates (± SE) of 47.6% ± 12.1% (95% CI, 28.9% to 78.4%) and 45.6% ± 11.7% (95% CI, 27.6% to 75.5%), respectively. Time to relapse ranged from 4 to 132 months. Most patients who experienced relapse died within 1 year. Febrile neutropenia, hearing loss, and endocrinopathy were the most common treatment-related complications.
CONCLUSION: The survival rate of childhood MB in Malaysia is inferior to that usually reported in the literature. We postulate that the following factors contribute to this difference: lack of a multidisciplinary neuro-oncology team, limited health care facilities, inconsistent risk assessment, insufficient data in the National Cancer Registry and pathology reports, inadequate long-term follow-up, and cultural beliefs leading to treatment abandonment.
PMID: 28717752 [PubMed]
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Different renal phenotypes in related adult males with Fabry disease with the same classic genotype.
Mol Genet Genomic Med. 2017 Jul;5(4):438-442
Authors: Mignani R, Moschella M, Cenacchi G, Donati I, Flachi M, Grimaldi D, Cerretani D, Giovanni P, Montevecchi M, Rigotti A, Ravasio A
Abstract
BACKGROUND: Fabry disease related patients with classical mutation usually exhibit similar severe phenotype especially concerning renal manifestation.
METHODS: A dry blood spot screening (DBS) and the DNA analysis has been performed in a 48-year-old man (Patient 1) because of paresthesia.
RESULTS: The DBS revealed absent leukocyte α-Gal A enzyme activity while DNA analysis identified the I354K mutation. Serum creatinine and e-GFR were in normal range and also albuminuria and proteinuria were absent. The brain MRI showed ischemic lesions and a diffuse focus of gliosis in the white matter, while the echocardiogram showed a left ventricular hypertrophy. The renal biopsy performed in the case index showed a massive deposition of zebra bodies. By a familiar investigation, it was recognized that his brother (Patient 2) died 2 years before from sudden death syndrome at the age of 49. He had suffered sporadic and undiagnosed pain at the extremities, a prior cataract, bilateral neurosensorial hearing loss and left ventricular hypertrophy on Echocardiogram. His previous laboratory examinations revealed a normal serum creatinine and the absence of proteinuria. Pedigree analysis of the brothers revealed a high disease burden among family members, with an affected cousin (Patient 3) who progressed early to end-stage renal disease (ESRD) that required renal transplantation.
CONCLUSIONS: Here we describe the clinical history of three adult male members of the same family with the same genotype who manifested different presentation and progression of the disease, particularly concerning the renal involvement.
PMID: 28717668 [PubMed]
