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Objective: This paper highlights the importance of reporting air–bone gap closure in stapes surgery according to the American Academy of Otolaryngology – Head and Neck Surgery guidelines and reviews compliance in recent years. Methods: A retrospective case series was conducted and the outcomes were reviewed. Closure of the air–bone gap was calculated in 204 adult patients using the aforementioned guidelines. Results were recalculated ignoring the Carhart phenomenon to determine any significant difference. Adherence to guidelines was also reported as a secondary outcome. Results: Ignoring the Carhart phenomenon resulted in 75 per cent over-reporting of successful air–bone gap closure (p < 0.001). Over-reporting occurred in 5.9 per cent of papers, and in 11.8 per cent it was difficult to determine how the results were reached. Conclusion: Despite the existence of clear guidelines, stapes surgery outcomes are still being over-reported as successful. This can lead to incorrect information being provided to patients during the consent process and makes comparative studies difficult. [ABSTRACT FROM AUTHOR]

Chromosome number and position of rDNA were studied in 12 wild and cultivated species of the genus Capsicum with chromosome numbers x = 12 and x = 13 (22 samples). For the first time in these species, the 5S and 45S rRNA loci were localized and physically mapped using two-color fluorescence in situ hybridization and AgNOR banding. We focused on the comparison of the results obtained with both methods with the aim of accurately revealing the real functional rRNA genes. The analyzes were based on a previous work that reported that the 18S-5.8S-25S loci mostly coincide with GC-rich heterochromatic regions and likely have given rise to satellite DNAs, which are not active genes. These data show the variability of rDNA within karyotypes of the genus Capsicum, providing anchor points for (comparative) genetic maps. In addition, the obtained information might be useful for studies on evolution of repetitive DNA. [ABSTRACT FROM AUTHOR]

Linked article: This Correspondence comments on Lapa et al. Click here to view the article. [ABSTRACT FROM AUTHOR]

Accumulation of amyloid-β peptides (Aβ) and cholinergic degeneration are hallmarks of Alzheimer's disease (AD). In a triple transgenic mouse model of AD (3xTg-AD), soluble Aβ42 levels were detected in the septum by 2 months of age, reaching their highest levels at 3-6 months and decreasing at 12 months. Deficits in the number of septal cholinergic neurons and the length of hippocampal cholinergic axons were observed starting at 4 months in 3xTg-AD mice. Our results show that septal Aβ and septohippocampal cholinergic pathology in 3xTg-AD mice occur at an early stage of disease. [ABSTRACT FROM AUTHOR]

Abstract: Cholinergic deficits occur in the aged hippocampus and they are significant in Alzheimer''s disease. Using stereological and biochemical approaches, we characterized the cholinergic septohippocampal pathway in old (24 months) and young adult (3 months) rats. The total length of choline acetyltransferase (ChAT)-positive fibers in the dorsal hippocampus was significantly decreased by 32% with aging (F (1,9) =20.94, p =0.0014), along with the levels of synaptophysin, a presynaptic marker. No significant changes were detected in ChAT activity or in the amounts of ChAT protein, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tropomyosin related kinase receptor (Trk) A, TrkB, or p75 neurotrophin receptor (p75NTR) in the aged dorsal hippocampus. The number and size of ChAT-positive neurons and the levels of ChAT activity, NGF and BDNF were not statistically different in the septum of aged and young adult rats. This study suggests that substantial synaptic loss and cholinergic axonal degeneration occurs during aging and reinforces the importance of therapies that can protect axons and promote their growth in order to restore cholinergic neurotransmission. [Copyright &y& Elsevier]

The development of efficient systems for in vivo gene transfer to the central nervous system (CNS) may provide a useful therapeutic strategy for the alleviation of several neurological disorders. In this study, we evaluated the feasibility of nonviral gene therapy to the CNS mediated by cationic liposomes. We present evidence of the successful delivery and expression of both a reporter and a therapeutic gene in the rodent brain, as evaluated by immunohistochemical assays. Our results indicate that transferrin-associated cationic liposome/DNA complexes (Tf-lipoplexes) allow a significant enhancement of transfection activity as compared to plain complexes, and that 8/1 (+/−) Tf-lipoplexes constitute the best formulation to mediate in vivo gene transfer. We demonstrated that Tf-lipoplex-mediated nerve growth factor transgene expression attenuates the morphological damages of the kainic acid-induced lesion as assessed by 2,3,5-triphenyltetrazolium chloride (TTC) vital staining. These findings suggest the usefulness of these lipid-based vectors in mediating the delivery of therapeutic genes to the CNS.Gene Therapy (2005) 12, 1242–1252. doi:10.1038/sj.gt.3302516; published online 7 April 2005 [ABSTRACT FROM AUTHOR]

The development of methodologies for gene transfer into the central nervous system is crucial for gene therapy of neurological disorders. In this study, different cationic liposome formulations were used to transfer DNA into C6 glioma cells and primary hippocampal and cortical neurons by varying the nature of the helper lipid (DOPE, Chol) or a mixture of DOPE and cholesterol (Chol) associated to DOTAP. In addition, the effect of the lipid/DNA (+/−) charge ratio, the association of the ligand transferrin to the lipoplexes, and the stage of differentiation of the primary cells on the levels of transfection activity, transfection efficiency, and duration of gene expression were evaluated. Mechanistic studies were also performed to investigate the route of delivery of the complexes into neurons. Our results indicate that DOTAP:Chol (1:1 mol ratio) was the best formulation to transfer a reporter gene into C6 glioma cells, primary hippocampal neurons, and primary cortical neurons. The use of transferrin-associated lipoplexes resulted in a significant enhancement of transfection activity, as compared to plain lipoplexes, which can be partially attributed to the promotion of their internalization mediated by transferrin. While for hippocampal neurons the levels of luciferase gene expression are very low, for primary cortical neurons the levels of transgene expression are high and relatively stable, although only 4% of the cells has been transfected. The stage of cell differentiation revealed to be critical to the levels of gene expression. Consistent with previous findings on the mechanisms of cell internalization, the experiments with inhibitors of the endocytotic pathway clearly indicate that transferrin-associated lipoplexes are internalized into primary neurons by endocytosis. Promising results were obtained in terms of the levels and duration of gene expression, particularly in cortical neurons when transfected with the Tf-associated lipoplexes, this finding suggesting the usefulness of these lipid-based carriers to deliver genes within the CNS. [Copyright &y& Elsevier]

The Museu da Ciência da Universidade de Coimbra (MCUC) (Science Museum of the University of Coimbra) hosts an important historical collection of land and freshwater snails from the Madeira Archipelago. This collection of 1,768 specimens (120 recent taxa within 20 families) was recently catalogued and digitized. Specimens in MCUC collections were recognized as being provided by António da Costa Paiva (Barão de Castelo de Paiva). This Portuguese nobleman also donated other mollusc collections to different scientific institutions and natural history museums in Portugal and abroad in the mid nineteenth-century. The study of the origin of the MCUC mollusc collection, beyond the data associated with the specimens, is important to the research on the endangered fauna of the Madeira Archipelago. This work precedes a comprehensive study ongoing in MCUC regarding the species occurrence and the systematic review on a great number of species hosted in the museum collection. [ABSTRACT FROM AUTHOR]

Objective: We report a case of Sweet's disease associated with rapid, profound loss of hearing, against a background of progressive, bilateral, sensorineural hearing loss. Results: The clinical features were indistinguishable from those of immune-mediated inner ear disease. Establishment of a definitive diagnosis was a challenge due to the absence of a reliable diagnostic test. The patient was unresponsive to extensive immunosuppressive therapy and subsequently underwent cochlear implantation, with good hearing outcomes. Conclusions: Profound, bilateral, sensorineural hearing loss in the context of Sweet's disease may be related to the underlying immunological aetiology. Cochlear implantation can successfully restore hearing when immunotherapy fails. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to audit middle-ear surgical procedures, provide a record of Australian experiences and allow comparisons with other published audits. Method: A retrospective continuous series audit was conducted on 274 patients who underwent tympanoplasty, mastoidectomy and stapedotomy surgery at Westmead Hospital, Sydney. All consecutive surgical procedures, performed by multiple operators at various stages of training but under the care of a single surgeon, were included. Results: Graft uptake was 86.9 per cent in tympanoplasty. Well healed cavities were seen in 72 per cent of mastoidectomies. Although 42 per cent of the patients had one or more co-morbidities, this did not influence the outcome. Hearing improvement was dramatic in stapedotomy and minimally changed in mastoidectomy. Post-operative complications were minimal. Conclusion: All forms of middle-ear surgery were effective in achieving their surgical goals. Aural discharge and inflammatory diseases were well controlled with tympanoplasty and mastoid surgery. [ABSTRACT FROM AUTHOR]

Objective:To assess the face and content validity of a novel synthetic, three-dimensional printed temporal bone for surgical skills development and training.Methods:A synthetic temporal bone was printed using composite materials and three-dimensional printing technology. Surgical trainees were asked to complete three structured temporal bone dissection exercises. Attitudes and impressions were then assessed using a semi-structured questionnaire. Previous cadaver and real operating experiences were used as a reference.Results:Trainees’ experiences of the synthetic temporal bone were analysed in terms of four domains: anatomical realism, usefulness as a training tool, task-based usefulness and overall reactions. Responses across all domains indicated a high degree of acceptance, suggesting that the three-dimensional printed temporal bone was a useful tool in skills development.Conclusion:A sophisticated three-dimensional printed temporal bone that demonstrates face and content validity was developed. The efficiency in cost savings coupled with low associated biohazards make it likely that the printed temporal bone will be incorporated into traditional temporal bone skills development programmes in the near future. [ABSTRACT FROM PUBLISHER]

Abstract Common marmosets are members of the family Callitrichidae, South American primates characterized by highly social group living and cooperative breeding. In this study we analysed 1112 base pairs (bp) of the mitochondrial control region in 59 Callithrix jacchus individuals, sampled mainly from two geographically distinct field sites in N.E. Brazil. Analysis of molecular variation revealed a highly significant genetic structuring of haplotypes between social groups and between populations. Examination of matrilineal genetic structure within social groups revealed that seven of nine recorded breeding pairs were from different maternal lineages, indicating assortative mating and outbreeding. In addition to the breeders, at least six of 10 groups contained adult individuals from different matrilines, with five haplotypes present in one social group of nine animals. Groups of mixed lineages raise questions about potential reproductive conflicts of interest, and the extent of kin-selected altruism in the evolution and maintenance of cooperative breeding in this species. [ABSTRACT FROM AUTHOR]

Although science and technology impact every aspect of modern societies, there is still an extensive gap between science and society, which impairs the full exercise of citizenship. In the particular case of biomedical research increased investment should be accompanied by parallel efforts in terms of public information and engagement. We have carried out a project involving the production and evaluation of educational contents focused on stem cells - illustrated newspaper chronicles, radio interviews, a comic book, and animated videos - and monitored their impact on the Portuguese population. The study of the outreach materials in a heterogeneous sample of the population suggests that they are valuable tools to disseminate scientific messages, and that this is especially true for the comic-book format. Furthermore, the data showed that clear and stimulating outreach materials, that are able to teach new concepts and to promote critical thinking, increase engagement in science at different levels, depending on the depth of the concepts involved. Additionally, these materials can influence political, social and personal attitudes toward science. These results, together with the importance attributed to scientific research in stem cells by the population sampled, validates the diffusion of such materials as a significant contribution towards an overall public understanding and engagement in contemporary science, and this strategy should thus be considered in future projects. Regardless, stringent quality control must be implemented in order to efficiently communicate accurate scientific developments, and the public stimulated in terms of finding additional sources of reliable information. [ABSTRACT FROM AUTHOR]

Skull-base osteomyelitis (SBO) occurs secondary to invasive bacterial and fungal infection. Distinguishing between fungal and bacterial aetiologies of SBO has significant therapeutic implications. An 18-year (1990-2007) retrospective review of patients with SBO presenting to Westmead Hospital was performed. Epidemiological, clinical, laboratory and radiology data were collated. Twenty-one patients (median age 58 years) with SBO were identified: ten (48%) had bacterial and 11 (52%) had fungal SBO. Diabetes mellitus (57%) and chronic otitis externa (33%) were the most frequent co-morbidities; immunosuppression was present in five cases (24%). Cranial nerve deficits occurred in ten (48%) patients. The commonest pathogens were Pseudomonas aeruginosa (50% bacterial SBO) and a zygomycete (55% fungal SBO). Compared to bacterial SBO, fungal SBO was more frequently associated with underlying chronic sinusitis, sinonasal pain, facial/periorbital swelling and nasal stuffiness or discharge and the absence of purulent ear discharge (all p <0.05). Bacterial SBO was more frequently associated with deafness, ear pain or ear discharge (all p <0.05). Median time to presentation was longer in patients with bacterial SBO (26.3 weeks vs. 8.1 weeks, p 0.08). Overall 6-month survival was 88% (14/18 patients). All four deaths occurred in patients with fungal SBO. Immunosuppression was a risk factor for death (p <0.05). Early diagnostic sampling is recommended in patients at increased risk of fungal SBO to enable optimal antimicrobial and surgical management. [ABSTRACT FROM AUTHOR]

When performed with a multi-detector system, γγ directional correlation measurements need to be corrected differently for each independent detector pair, especially when those detectors have different active volumes and subtend different solid angles with respect to the radioactive source. We show here a method, which is suitable for setups containing dissimilar detectors. Successful tests were made for four γγ cascades, from 60Co, 133Ba and 152Eu. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the optical band-gap energy of mercuric iodide grown by sublimation in a sealed ampoule by photoacoustic spectroscopy. Information on the article on the use of mercuric iodide as a room-temperature detector; Discussion of an important parameter in electronic and optoelectronic design; Procedures used to obtain a high-purity mercuric iodide.