In Sao Tome and Principe there are approximately five thousand deaf and hard-of-hearing individuals. Until recently, these people had no language to use among them other than basic home signs used only to communicate with their families. With this communication gap in mind, a project was set up to help them come together in a common space in order to create a dedicated environment for a common sign language to emerge.In less than two years, the first cohort began to sign and to develop a newly emerging sign language – the Sao Tome and Principe Sign Language (LGSTP). Signs were elicited by means of drawings and pictures and recorded from the beginning of the project. The emergent structures of signs in this new language were compared with those reported for other emergent sign languages such as the Al-Sayyid Bedouin Sign Language and the Lengua de Señas de Nicaragua, and several similarities were found at the first stage.In this preliminary study on the emergence of LGSTP, it was observed that, in its first stage, signs are mostly iconic and exhibit a greater involvement of the articulators and a larger signing space when compared with subsequent stages of LGSTP emergence and with other sign languages. Although holistic signs are the prevalent structure, compounding seems to be emerging. At this stage of emergence, OSV seems to be the predominant syntactic structure of LGSTP. Yet the data suggest that new signers exhibit difficulties in syntactic constructions with two arguments.
Rubella infection can affect several organs and cause birth defects that are responsible for congenital rubella syndrome (CRS). Congenital hearing loss is the most common symptom of this syndrome, occurring in approximately 60% of CRS cases. Worldwide, over 100 000 babies are born with CRS every year. There is no specific treatment for rubella, but the disease is preventable by vaccination. Since 1969, the rubella vaccine has been implemented in many countries, but in Africa, only a few countries routinely immunize against rubella. The aim of this study was to estimate the rate of infection from the wild-type rubella virus in São Tomé and Príncipe by determining rubella seroprevalence with a DBS method. The goal of this study was to reinforce the need for implementation of the rubella vaccine in this country. As secondary objectives, the validation of a DBS method was first attempted and an association between seroprevalence and hearing loss was assessed. We collected samples from individuals observed during humanitarian missions in São Tomé and Príncipe. All individuals underwent an audiometric evaluation, and a drop of blood was collected for the dried blood spot (DBS). We define two groups: the case group (individuals with unilateral or bilateral hearing loss (HL)) and the control group (individuals with two normal ears). Patients were excluded if they suffered from conductive HL, if they showed evidence of possible causes of HL, if they had developmental delay or if they refused to participate in the study. Among the 315 subjects, we found 64.1% individuals with IgG for the rubella virus, 32.1% without immunity for the rubella virus and 3.8% who were borderline. In the control group, 62.6% were positive for the rubella IgG, whereas in the case group, 72% were positive. Analyzing both groups, with ages ranging from 2 to 14 years of age and from 15 to 35 years of age, we found a seroprevalence of 50.3% to rubella in the younger group and 82.1% in the older group, with a significant difference between cases and control group noted within the younger patients (p = 0.025). Rubella is a disease that can be prevented. Rubella infections are still very common in São Tomé and Príncipe, and women of child-bearing age are still at risk for rubella infection during pregnancy, justifying the urgency of vaccination against rubella. A statistically significant association between the group of children under 14 years of age with HL and immunity for rubella was observed in this country, although this study did not allow us to establish a cause-effect relationship between rubella infection and SNHL.
25 October 2021 in International Journal for Numerical Methods in Biomedical Engineering
Hearing loss (HL) is a common condition with both genetic and environmental causes, and it greatly impacts global health. The prevalence of HL is reportedly higher in developing countries such as the Sub-Saharan African island of São Tomé and Príncipe, where the deaf community is estimated to be less than 1% of the population. We investigated the role of the DFNB1 locus ( GJB2 and GJB6 genes) in the etiology of nonsyndromic sensorineural hearing loss (NSSHL) in São Tomé and Príncipe. A sample of 316 individuals, comprising 136 NSSHL patients (92 bilateral, 44 unilateral) and 180 controls, underwent a clinical and audiological examination. Sequencing of the GJB2 coding region and testing for the ( GJB6 -D13S1830) and del( GJB6 -D13S1854) GJB6 deletions were performed. A total of 311 out of 316 individuals were successfully analyzed regarding the GJB2 and GJB6 genetic variations, respectively. The frequency of the GJB2 coding mutations in patients and controls was low. Some of those coding mutations are the most commonly found in Eurasian and Mediterranean populations and have also been identified in Portugal. None of the GJB6 deletions was present. The presence of certain coding variants in São Tomé and Príncipe suggests a non–Sub-Saharan genetic influx and supports the previously reported genetic influx from European (mainly Portuguese) ancestors. In summary, DFNB1 locus does not appear to be a major contributor to NSSHL in São Tomé and Príncipe. However, the presence of both pathogenic and likely pathogenic mutations in GJB2 suggests that GJB2 -related NSSHL might still occur in this population, warranting further research on GJB2 testing in NSSHL cases.
Obstructive sleep apnea is a sleep disorder with a high prevalence in the world population. The mandibular advancement device is one of the options for treating obstructive sleep apnea. Neck computed tomography and drug-induced sleep endoscopy are complementary diagnostic tests that may help predict the effectiveness of mandibular advancement devices. This study aims to analyze the best method for predicting the effectiveness of mandibular advancement devices in the therapeutic approach to obstructive sleep apnea. PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science Core Collection databases will be comprehensively searched. We will include randomized clinical trials, non-randomized prospective or retrospective clinical studies, case controls, cohort studies, and case series. Two authors will independently conduct data extraction and assess the literature quality of the studies. The analysis of the included literature will be conducted by Revman 5.3 software. The outcomes that will be analyzed are craniofacial characteristics, cephalometric assessments, site and type of obstruction of the upper airway, mean values of the apnea–hypopnea index, and SaO2 verified in the initial and follow-up polysomnography. This study will provide reliable, evidence-based support for the clinical application of mandibular advancement devices for obstructive sleep apnea.
Study objectives: Obstructive sleep apnea (OSA) has a high prevalence in the global population and is a significant sleep disorder. One of the non-invasive options to treat obstructive sleep apnea is the mandibular advancement device. 2 methods can help predict the success of mandibular advancement devices, and they are Neck computed tomography (CT) and Drug-induced Sleep endoscopy (DISE). The objective of this study was to determine which method is better at predicting the success of a mandibular advancement device in the treatment of obstructive sleep apnea. Methods: PubMed, Embase and Web of Science Core Collection databases were comprehensively searched. A total of 1809 was obtained through the extensive search of the three databases mentioned above (Embase = 952; PubMed = 508; Web of Science = 349). The exclusion criteria were studies lacking clear and replicable methodologies; research involving pediatric and adolescent participants, as well as individuals with craniofacial malformations; and Animal studies, conference abstracts, editorials, case reports, book chapters, and review articles. Results: Based on the inclusion criteria, mainly because of the lack of direct comparison between CT and DISE for the prediction of MAD success, two articles were selected for this systematic review. The conflicting findings between the two studies underscore the complexity of OSA management and challenges associated with predicting treatment outcomes using different diagnostic modalities. Conclusions: Although CT offers detailed anatomical information regarding airway morphology, DISE provides dynamic visualization of upper airway collapse during sleep, which may better simulate real-life conditions and MAD responses.