Environmental exposure to heavy metals such as cobalt (Co), lead (Pb), and zinc (Zn) has been implicated in carcinogenesis, yet few studies have quantified their levels directly in tumor tissues, particularly in North African populations. In this study, we measured Co, Pb, and Zn concentrations in paired tumor and adjacent normal tissue biopsies from 73 Tunisian patients with cancers of the upper aerodigestive tract (UADT), including squamous cell carcinomas of the larynx, pharynx, and oral cavity. Metal levels were determined using Graphite Furnace Atomic Absorption Spectrometry (GF-AAS). Analyses compared tumor and normal tissues while exploring associations with patient demographics, smoking status, occupational exposure, and tumor stage. We observed significantly higher concentrations of Co, Pb, and Zn in tumor tissues (0.06, 0.08 and 32.25 µg/g, respectively) compared to matched normal tissues (Zn = 15.06 µg/g); Co and Pb were often undetectable in healthy samples. Although metal levels tended to be higher in men and tobacco users, these differences were not statistically significant. Notably, cobalt levels varied significantly across nodal tumor stages, with N1 tumors exhibiting the highest concentrations. Moreover, lead levels varied slightly but significantly across T classifications, while Zn showed no stage-dependent differences. Additionally, a significant negative correlation was found between age and tumoral Zn concentration (Spearman’s rho = − 0.26, p = 0.024). These findings provide the first comprehensive evidence, both in a Tunisian cohort and globally, that Co, Pb, and Zn accumulate in tumor tissues across multiple UADT sites. The results highlight a potential role for these metals in tumor biology and suggest they may serve as biomarkers or contribute to carcinogenic mechanisms in UADT cancers, warranting further investigation in larger populations and mechanistic studies.

To establish easily measurable and reproducible preoperative parameters predicting difficult laryngeal exposure in direct laryngoscopy. A prospective study including 71 patients who underwent transoral microsurgery for benign or malignant lesions of the larynx was performed in our department from January 2021 to November 2021. Physical assessment included the Mallampati score, weight, height, body mass index and measurements of seven parameters in the cervical region. Eleven parameters were measured on the cervical radiography film. Among our patients, 19 were included in the difficult laryngeal exposure (DLE) group. High Mallampati and Cormack scores were significantly associated with DLE (p = 0.005 and p < 0.0001). Limited mouth opening, direct thyromental distance (DTMD) < 67 mm in neutral position, DTMD < 82 mm and sternomental distance < 157 mm at full head extension were statistically related to DLE. For radiological assessment, the effective length of the maxilla and the atlanto-occipital distance were related to DLE. Using stepwise logistic regression, only the effective length of the maxilla and atlanto-occipital distance were selected as independent predictors for DLE (p: 0.015 and 0.001). Preoperative prediction of DLE is useful for both surgeons and patients. The length of the maxilla and the atlanto-occipital distance were found to be independent risk factors for DLE. This highlights the effect of overgrowth of the maxilla, protrusion of the upper teeth and limited extension of the cervical spine as the major risk factors for difficult laryngeal exposure.

Objective: Our aim is to evaluate the effect of topical tranexamic acid (TA) on bleeding and surgical quality field in the functional endoscopic sinus surgery (FESS). Methods: A total of 74 patients who underwent FESS due to chronic rhinosinusitis were included. The patients were randomized into 2 groups. TA group (n = 37) received a topical cotton pledget soaked with TA and placebo (PL) group (n = 37) received a pledget soaked with saline solution. Results: A significant effect was noted for the TA group versus the PL group in the grade 1 of the Boezaart scale at 35 minutes (4 for TA group and no case for PL group). This effect was absent for higher grades. We did not notice a significant effect between the 2 groups at 5 minutes. Blood loss was 359 ml in the TA group versus 441 ml in the PL group. No significant change was observed between the 2 groups concerning the blood parameters. No side effects were reported. Conclusion: Despite its safety when administrated locally and its low cost, TA provides limited effect on quality of surgical field after 35 minutes of the start of FESS in the patients with chronic rhinosinusitis. This effect was absent at the start of the intervention and when analyzing the blood loss and hematologic parameters.

Background Otosclerosis (OTSC) is among the most common causes of a late-onset hearing loss in adults and is characterized by an abnormal bone growth in the otic capsule. Alteration in the osteoprotegerin (OPG) expression has been suggested in the implication of OTSC pathogenesis. Methods A case-control association study of rs2228568, rs7844539, rs3102734 and rs2073618 single nucleotide polymorphisms (SNPs) in the OPG gene was performed in a Tunisian-North African population composed of 183 unrelated OTSC patients and 177 healthy subjects. In addition, a multilocus association and a meta-analysis of existing studies were conducted. Results Rs3102734 ( p = 0.013) and rs2073618 ( p = 0.007) were significantly associated with OTSC, which were predominantly detected in females after multiple corrections. Among the OPG studied SNPs, the haplotypes A-A-C-G ( p = 0.0001) and A-A-C-C ( p = 0.0004) were significantly associated with OTSC in females. Multilocus association revealed that the SNPs: rs2073618 in OPG, rs1800472 in TGFβ1, rs39335, rs39350 and rs39374 in RELN , and rs494252 in chromosome 11 showed significant OTSC-associated alleles in Tunisian individuals. In addition, meta-analysis of the rs2073618 SNP in Tunisian, Indian and Italian populations revealed evidence of an association with OTSC (OR of 0.826, 95% CI [0.691–0.987], p = 0.035). Conclusions Our findings suggest that rs3102734 and rs2073618 variants are associated with OTSC in North African ethnic Tunisian population. Meta-analysis of the rs2073618 in three different ethnic population groups indicated an association with OTSC.

Introduction: Presbycusis, an age-related hearing impairment (ARHI) disease, is the most common cause for HI in adults worldwide. One of the best candidate genes for ARHI susceptibility is Cadherin 23 (CDH23) which encodes stereocilia tip-links of the inner ear sensory hair cell. Although alterations in the methylation status of CpG dinucleotides across various genes were reported to be associated with HI, methylation changes in CDH23 gene have not been reported previously. Objectives: This study aimed at investigating whether DNA methylation level of CDH23 gene at intragenic CpG island overlapping an exonic-intronic region at position chr10: 73565570-73565827 (GRCh37/hg19) could be risk factor associated with ARHI. Materials and Methods: We screened for methylation changes in this particular position for CDH23 gene in 50 blood samples of elderly women affected with presbycusis and healthy control cohort. Methylation of CpG sites were assessed using Quantitative methylation-specific PCR (qMSP) following sodium bisulfite DNA conversion chemistry. Methylation levels were normalized against TSH2B reference gene. Results: DNA methylation analysis for the common CpG islands in CDH23 gene revealed 3.27-folds significant increase (p < 0.0001) in methylation profile for ARHI women as compared to healthy controls with an elevated risk odds ratio (OR) of 2.219 [95% CI 1.071-4.597]. Conclusion: Our study is the first of its kind to prove that higher CpG site methylation levels in CDH23 gene are likely to be associated with ARHI.

Alstrom syndrome is a clinically complex disorder characterized by progressive degeneration of sensory functions, resulting in visual and audiological impairment as well as metabolic disturbances. It is caused by recessively inherited mutations in the ALMS1 gene, which codes for a centrosomal/basal body protein.The purpose of this study was to investigate the genetic and clinical features of two Tunisian affected siblings with Alstrom syndrome.Detailed clinical examinations were performed including complete ophthalmic examination, serial audiograms and several biochemical and hormonal blood tests. For the molecular study, first genomic DNA was isolated using a standard protocol. Then, linkage analysis with microsatellite markers was performed and DNA array was used to detect known mutations. Subsequently, all ALMS1 exons were simultaneously sequenced for one affected patient with the TaGSCAN targeted sequencing panel. Finally, segregation of the causal variant was performed by Sanger sequencing.Both affected siblings had cone rod dystrophy with impaired visual acuity, sensorineural hearing loss and truncal obesity. One affected individual showed insulin resistance without diabetes mellitus. Other clinical features including cardiac and pulmonary dysfunction, hypothyroidism, hyperlipidemia, acanthosis nigricans, renal and hepatic dysfunction were absent. Genetic analysis showed the presence of a homozygous splice site mutation (c.10388-2A > G) in both affected siblings.Although Alstrom syndrome is relatively well characterized disease, this syndrome is probably misdiagnosed in Tunisia. Here, we describe the first report of Tunisian patients affected by this syndrome and carrying a homozygous ALMS1 mutation. The diagnosis was suspected after long-term clinical follow-up and confirmed by genetic testing. (C) 2016 Elsevier Masson SAS. All rights reserved.

Hearing impairment (HI) is the most frequent sensory defect. Genetic causes are involved in two thirds of prelingual cases. Moreover, the autosomal recessive HI frequency is increased in countries where there is a high rate of consanguinity, such as in North African Mediterranean countries. This population shares several features, including history and social behavior, that promote the spread of founder mutations. HI is characterized by tremendous heterogeneity in both the genetic and clinical aspects. The identification of the causal mutation is important for early diagnosis, clinical follow-up, and genetic counseling. Addressing the extreme genetic heterogeneity of HI using classic molecular methods would be expensive and time-consuming. We designed a cost-effective North African Deafness chip for rapid and simultaneous analysis of 58 mutations using multiplex PCR coupled with dual-color arrayed primer extension. These mutations are found in North African HI patients and are distributed over 31 exons and five introns in 21 distinct genes. Assay specificity was initially optimized using 103 archived DNA samples of known genotypes. Blind validation of HI-unrelated patients revealed mutant alleles in 13 samples, and these mutations were confirmed by Sanger sequencing. The North African Deafness chip allows for simultaneous genotyping of eight different samples, at a minimal cost and in a single day, and is therefore amenable to large-scale molecular screening of HI in North Africa.

Hearing loss (HL) is a major public health issue. It is clinically and genetically heterogeneous.The identification of the causal mutation is important for early diagnosis, clinical follow-up, and genetic counseling. HL due to mutations in COL11A2 , encoding collagen type XI alpha-2, can be non-syndromic autosomal-dominant or autosomal-recessive, and also syndromic as in Otospondylomegaepiphyseal Dysplasia, Stickler syndrome type III, and Weissenbacher–Zweymuller syndrome. However, thus far only one mutation co-segregating with autosomal recessive non-syndromic hearing loss (ARNSHL) in a single family has been reported. In this study, whole exome sequencing of two consanguineous families with ARNSHL from Tunisia and Turkey revealed two novel causative COL11A2 mutations, c.109G > T (p.Ala37Ser) and c.2662C > A (p.Pro888Thr). The variants identified co-segregated with deafness in both families. All homozygous individuals in those families had early onset profound hearing loss across all frequencies without syndromic findings. The variants are predicted to be damaging the protein function. The p.Pro888Thr mutation affects a -Gly-X–Y- triplet repeat motif. The novel p.Ala37Ser is the first missense mutation located in the NC4 domain of the COL11A2 protein. Structural model suggests that this mutation will likely obliterate, or at least partially compromise, the ability of NC4 domain to interact with its cognate ligands. In conclusion, we confirm that COL11A2 mutations cause ARNSHL and broaden the mutation spectrum that may shed new light on genotype–phenotype correlation for the associated phenotypes and clinical follow-up.

Schwannomas (neurilemmomas) are benign tumors arising from the Schwann cells of the neural sheath. They are typically, well-encapsulated lesions which rarely adhere to the adjacent structures. In the chest, schwannomas are often seen within the posterior mediastinum and commonly originating along intercostal nerves. Several operative approaches have previously been described for the resection of these tumors, including thoracoscopic techniques and posterolateral thoracotomy. We report in this case a giant cystic mediastinal schwannoma of the left recurrent laryngeal nerve with cervical extension, unresectable by the usual described approaches, which was completely removed through a cervical approach.

Although the pathophysiology underlying nasal polyposis (NP) formation is not fully understood, systemic, local, and environmental factors appear to contribute to NP disease development. This study aimed to explore the relationship between metal blood levels and NP risk. To the best of our knowledge, the current research represents the first scientific contribution reporting levels of Cr and As in blood of NP patients. In this context, 90 NP patients and 171 controls were recruited and blood samples were analyzed to determine the concentrations of As and Cr. Metal blood levels of As in patients (2.1 μg/L) were significantly higher than those of controls (1.2 μg/L). However, no significant difference in blood Cr levels was found between cases and controls. Arsenic blood levels of cigarette smokers were significantly higher than those of non-smokers. Environmental exposure and shisha consumption presented the most significant association with NP disease (OR = 10.1 and 14.1, respectively). High levels of blood As were significantly associated with NP disease (OR = 2.1). Cr blood levels were found to be associated with the four stages of polyps in both nasal cavities. This study found a strong association between nasal polyposis disease and As blood levels. These findings merit further investigation.

Several studies have shown that many polymorphisms of the xenobiotic-metabolizing enzymes (XME) affect either enzymatic functions or are associated with various aspects of human health. Owing to the presence of these single nucleotide variants (SNVs), differences in detoxification capacity have been observed between many ethnicities. The aim of this investigation was to study the prevalence of four polymorphisms in XME among various ethnic groups. Attention was focused on polymorphisms of CYP2D6 (rs1058172, G>A, p.Arg365His), CYP1A1 (rs4646421, c.-26-728C>T), NAT1 (rs4921880, c.-85-1014T>A) and NAT2 (rs1208, A>G, p.Arg268Lys). These polymorphisms were analyzed in 261 healthy Tunisians individuals in comparison with different ethnic backgrounds from hapmap database. In addition, in silico functional prediction was also performed to determine the loss of function variants. Our results demonstrated that population's origins widely affect the genetic variability of XME enzymes and Tunisians show a characteristic pattern. In silico predictions showed a deleterious effect for p.Arg268Lys substitution on CYP2D6 function, findings confirmed its key role played in cancer susceptibility. These data show that detoxification genes structures depend on the studied population. This suggests that ethnic differences impact on disease risk or response to drugs and therefore should be taken into consideration in genetic association studies focusing on XME enzymes. Our results provide the first report on these SNV in Tunisian population and could be useful for further epidemiological investigations including targeted therapy.

The purpose of this study was to investigate the relationship between head and neck cancer (HNC) and environmental agents and polymorphisms in CYP1A1, CYP2D6, NAT1 and NAT2 metabolic enzymes genes. To the best of our knowledge, this is the first report on polymorphisms in CYP1A1 6310C > T, CYP2D6 Arg365His, NAT1 52936A > T and NAT2 Arg268Lys (NAT2*12A) genes and susceptibility to HNC in Tunisian population. We study the prevalence of these polymorphisms in 169 patients with HNC and 261 control subjects using polymerase chain reaction based methods in a Tunisian population. We detected an association between HNC and CYP1A1 6310C > T (TT) and CYP2D6 Arg365His (His/His) variant carriers (OR 1.75, P = 0.008 and OR 1.66, P = 0.016, respectively). No association was found between the polymorphisms genotypes of NAT1 52936T > A and NAT2 Arg268Lys and risk of HNC. An association between HNC and CYP1A1 (TT) genotype was found among patients with smoking (P = 0.011) and drinking habit (P = 0.009). The combinations of NAT1 (AT or AA) and NAT2 (AA) at-risk genotypes increased HNC risk (OR 4.23, P = 0.005 and OR 3.60, P = 0.048, respectively). However, the combinations of CYP1A1 (AA) and CYP2D6 (CC) genotypes decreased risk of HNC (OR 0.20; P = 0.006). Genetic polymorphisms in CYP1A1 and CYP2D6 may significantly associate with HNC in the Tunisian population. The results of this study suggest a possible gene-environment interaction for certain carcinogen metabolizing enzymes, but larger studies that fully evaluate the interaction are needed.

Despite growing evidence that bacteria, fungi, allergens, and superantigens play a prominent role in the pathophysiology of nasal polyps (NP), the exact cause of polyposis is still unknown. The etiology of NP is considered multifactorial. Until now, there is no information on the presence of heavy metals, such as cadmium (Cd), chromium (Cr), nickel (Ni), and arsenic (As) or of their role, in the pathogenesis of NP disease. In this study, concentrations of these four metals in tissue of NP were determined using Atomic Absorption Spectrometry. The Ni, Cr, and As levels in NP tissues were 2.1-, 3.2-, and 8.0-fold higher than those of normal mucosa (p < 0.05), respectively. A strong effect of cumulative smoking as expressed in the number of pack per year (PY), Ni, As, and Cd levels in NP tissue samples of patients ever-smokers (1–20 and >20 PY) are significantly higher than those of non-smokers (p = 0.006, 0.002, and < 0.001, respectively). The highest As concentrations among patients lived at polluted areas (1–25 and > 25 years) were observed in both nasal mucosa and NP tissues. The Ni and As in both nasal mucosa and NP tissues of patients occupationally exposed were significantly higher than non-exposed group. Cr and As levels were found to be associated with NP stage classification (p < 0.05). This is the first report to describe an association between concentrations of metals (Cr, As, and Ni) in human NP tissues and the risk of NP disease. Tissue metal levels have increased due to smoking, environmental, and occupational exposure. Therefore, heavy metal exposure may increase the risk of NP in the Tunisian population. The considerable risk in the category of highest cumulative exposure argues for an association between heavy metals exposure and nasal polyposis risk. Future investigations with larger samples should better elucidate this association.

Introduction: Postoperative, lingual swelling and necrosis are unusual complications that can lead to life-threatening airway obstruction. We report a case of bilateral ischemic necrosis of the tongue following transoral neurosurgical procedure. Observation: A Davis-Boyle mouth gag was used for tumor exposition and the operation lasted 8 h. At the end of the surgery, we noticed a bluish discoloration with a mild edema of the tongue. The patient had kept intubated in a monitored setting and intravenous steroids were administered. However, the edema increased and necrosis of the tongue appeared 72 h after the surgery. The patient underwent tracheotomy and the necrotic tissue was removed. More than 15 days passed before glossal engorgement resolved. Discussion: The etiology of tongue necrosis is likely related to tissue ischemia, secondary to venous or arterial obstruction. Prolonged use of the Davis-Boyle mouth gag may incur greater risk of ischemic necrosis of the tongue.

Chronic exposure to heavy metals has long been recognized as being capable to increase head and neck cancer incidence among exposed human populations. Head and neck cancer is a significant public health issue in Tunisia. The aim of the present study was to evaluate the concentrations of As, Cd, Cr and Ni in healthy and tumor tissues of head and neck cancer patients. Metal concentrations were determined in tumor and healthy tissues of 101 head and neck cancer patients, using Atomic Absorption Spectrometry. The As, Cd, Cr, and Ni levels in tumor tissues were 3.4, 2.5, 1.3 and 1.5 times higher than those of healthy tissues (p < 0.05), respectively. Tumor tissue metal levels were higher in men than in women. As and Cd levels in tumor and healthy tissue samples of patients smokers are significantly higher than those of non-smokers (p < 0.05). A strong effect of cumulative smoking as expressed in the number of pack per year, and tumor tissue Cd levels were positively associated with three groups of age (< 40, 51–60 and > 60 years) in both never-smokers and ever-smokers (< 20 and ≥ 20 pack per year). Healthy tissue Cd levels were negatively associated with age in those three groups of smokers. The highest Cd and Cr concentrations among both workers and non-workers were observed in tumor tissues. The Cd and Cr in tissues of farmers, bricklayers and painters were all significantly higher among the workers as compared with the non-workers group. Tissue metal levels have increased due to smoking and occupational exposure. Heavy metal exposure via tobacco smoking and occupational exposures may increase the risk of head and neck in the Tunisian population.

Chronic exposure to chromium (Cr) and nickel (Ni) has long been recognized as being capable to increase head and neck cancer (HNC) incidence among exposed human populations. This study represents the first biomonitoring of Cr and Ni exposure in Tunisia and focuses on a possible association with HNC risk. The aim of the present study was to evaluate the concentrations of Cr and Ni in the blood of HNC patients and controls. Metals blood levels of 169 HNC patients and 351 controls were determined using a Perkin-Elmer Analyst 800 Atomic Absorption Spectrometer. Mean blood levels of Cr and Ni in HNC cases (52.15 and 111.60 μg/L, respectively) were significantly higher than those of controls (37.04 and 30.50 μg/L, respectively). Cases' blood levels of Cr and Ni were significantly higher than those of controls after controlling for the other risk factors of HNC, including smoking, shisha consumption, occupational exposure, and nearby environment (P<0.05). Among these risk factors, smoking and occupational exposure presented the most significant association with HNC (odds ratio (OR)=6.54 and 7.66, respectively, P<0.001). Cr and Ni levels in blood sample of cases and controls that are smoker/occupationally exposed were higher than that of non-smoker/non-occupationally exposed (P<0.05). Smokers who are occupationally exposed present the most significant association with HNC (OR=25.08, P<0.0001). High levels of blood Cr (OR=2.09) and high levels of blood Ni (OR=8.87) were strongly associated with HNC after other potential confounders were controlled (P=0.004 and P<0.0001, respectively). This study suggested a potential role of Cr and Ni in the mechanism of HNC development.

Chromosome/DNA instability could be one of the primary causes of malignant cell transformation. The objective of the present study was to evaluate the spontaneous genetic damages in exfoliated cells of buccal mucosa of head and neck cancer (HNC) by counting micronucleus (MN) and binucleated (BN) cells frequencies. MN and BN frequencies were significantly increased in HNC patients compared with controls (5.53 ± 3.09/1000 cells, 5.63 ± 2.99/1000 cells versus 2.36 ± 2.11/1000 cells, 3.09 ± 1.82/1000 cells,P<0.001). Regarding the gender and the age, the frequencies of the MN and BN were significantly higher than those of controls (P<0.01). The evaluation of the MN and BN frequencies revealed a significant increase (P<0.001) in the cases in relation to the control group after controlling the risk factors (tobacco smoking and chewing and occupational exposure) of HNC. Moreover, MN and BN frequencies were significantly increased in smokers and chewers compared with nonsmokers and nonchewers among patients (P<0.05). MN frequency was significantly (P=0.014) different between patients occupationally exposed (6.99 ± 3.40/1000 cells) and nonexposed (4.70 ± 2.48/1000 cells) among HNC group. The logistic regression model illustrated that HNC was significantly associated with frequencies of MN (OR = 8.63,P<0.0001) and BN (OR = 5.62,P=0.001). Our results suggest that increased chromosome/DNA instabilities may be associated with HNC.

Neurosensorial hearing loss therapy to date has consisted mostly of the systemic administration of steroids and has been limited by their side effects and low therapeutic concentrations within the fluids and tissues of the inner ear. It has been shown in animals and humans that systemically applied glucocorticoids reach only low drug concentrations in the perilymph. The local application of drugs to treat inner ear diseases is expected to provide advantages as compared with systemic treatments, namely: 1) bypassing the bloodlabyrinthine barrier, 2) resulting in higher concentrations in the inner ear fluids 3) avoiding major unwanted effects of systemically administered medications.

In the case of an undifferentiated nasopharyngeal carcinoma coexisting with asymptomatic Paget’s disease it may be difficult to determine the stage. A case of a clinically localized nasopharyngeal carcinoma coexisting with incidental Paget’s disease is reported herein. A 51-year-old woman was admitted who presented a permanent left nasal obstruction, combined with ipsilateral epistaxis. She was diagnosed as having a nasopharyngeal carcinoma. The bone scan showed widespread homogenous increased remodelling throughout the skeleton. Radiographs showed an increase in bone density and cortical thickening. Magnetic resonance imaging (MRI) of the right leg excluded bone metastases. We concluded that this was a localized nasopharyngeal carcinoma associated with asymptomatic Paget’s disease of the bone. The patient showed a good response to concomitant radio chemotherapy. In imaging, the skeletal lesions of both nasopharyngeal cancer and Paget’s disease may closely resemble each other. No biological markers of bone resorption or formation can differentiate between the two entities. We used three radiological explorations to make the diagnosis. However we believe, after reviewing the literature, that fluorodeoxyglucose positron emission tomography (FDG PET) can be helpful in this situation.