Magnetic solid-phase extraction of organophosphorus pesticides from apple juice and environmental water samples using magnetic graphene oxide coated with poly(2-aminoterephthalic acid-co-aniline) nanocomposite as a sorbent.

An effective magnetic solid-phase extraction method was proposed using magnetic graphene oxide coated with poly(2-aminoterephthalic acid-co-aniline) as a sorbent for preconcentration and extraction of organophosphorus pesticides from environmental water and apple juice samples, and determined using the gas chromatography-mass spectrometry analysis. To approve the successful synthesis of the magnetic nanocomposite, the prepared sorbent was characterized by field emission scanning electron microscopy, X-ray diffraction, vibrating sample magnetometer, and Fourier transforms infrared techniques. The main parameters affecting the extraction efficiency were considered and studied to afford an optimized procedure. Systematic method validation verified its suitable recoveries (89.4-107.3%), and precision (relative standard deviations < 6.8%). The method showed a wide linear dynamic range (0.04-700 ng/mL) with low limits of detection (0.01-0.06 ng/mL) and quantification (0.04-0.21 ng/mL). This method presented good potential and great sensitivity for the pesticides determination.

Understanding corporate debt from the oil market perspective.

We design and test the hypothesis that for energy firms' oil market activities impact capital structure. Using a unique sample of 726 energy firms from 56 countries, we find that oil market activities do influence capital structure. The speed of adjustment (SOA) to leverage when not exposed to oil market activities is between 27.5 and 66.4%. When exposed to oil price growth (market liquidity) the corresponding SOA is between 51.1 and 72.4% (40.9-76.1%). We conclude that oil price growth slows down while market liquidity improves SOA to leverage for energy firms. By comparison, using a sample of over 32,000 non-energy firms from 108 countries, we find no evidence that oil market activities dictate capital structure.

A Challenge between Central Nervous System Infection and Lead Toxicity: Opioid Case Reports from Iran.

Although lead pollution has long been known as a cause of poisoning, it has remained a challenge to reliably diagnose it due to its common symptoms in various diseases. In this article, we report two cases of acute loss of consciousness due to the ingestion of opium-contaminated with lead. The reported cases share patterns of symptoms similar to meningitis and encephalitis which are usual etiology for the loss of consciousness. Lead poisoning is not a usual etiology for loss of consciousness and is considered in cases of occupational or environmental exposure. These reported cases showed a pattern similar to meningitis and encephalitis, but due to the unusual manifestations during their admission and coexistence with gastrointestinal symptoms, we were led to consider poisoning as the cause of consciousness loss. Lead poisoning often goes unrecognized due to a low index of suspicion, but it may turn out to be fatal. Therefore, it should be considered in the differential diagnosis of any neurobehavioral deficits in substance abusers.

Potential Effects of Climatic Parameters on Human Brucellosis in Fars Province, Iran, during 2009-2015.

BACKGROUND: Human brucellosis is widespread in Fars province. The present study aimed to investigate the effect of climate on its incidence and determine the areas prone to the infection. METHODS: Monthly meteorological data and the incidence rate of human brucellosis during 2009-2015 were collected and their correlation was studied using Pearson's correlation coefficient. Additionally, the multiple regression method and multi-layer perceptron neural network model were used to predict the incidence of human brucellosis. In order to analyze the data SPSS software (version 16.0), MATLAB software (version 8.1), and GIS software (version 10.4) were used. RESULTS: Pearson's regression analysis, on a monthly basis, showed a significant indirect correlation between the incidence of human brucellosis (with a time lag of up to 5 months) and climatic parameters (minimum temperature: -0.72 and evaporation: -0.73) in Abadeh (Fars, Iran). Moreover, there was a significant direct correlation (P<0.001) between the incidence of human brucellosis and the maximum relative humidity (+0.67) and rainfall (+0.48). The incidence of human brucellosis in Abadeh was predicted by using artificial neural network models (4 layers, 4 neurons in each layer), the Levenberg-Marquardt training algorithm, and Sigmoid transfer function. It was determined that a correlation rate of 0.89 in the training level and 0.8 in the test level (with the lowest error rate) were the best values in multi-layer perceptron modeling. CONCLUSION: Climatic parameters are important factors in determining the incidence rate of human brucellosis in Fars province. Climate conditions provide a favorable environment for the spread of human brucellosis in this area.

Glucagon-like peptide 1 decreases lipotoxicity in non-alcoholic steatohepatitis.

BACKGROUND & AIMS: Insulin resistance and lipotoxicity are pathognomonic in non-alcoholic steatohepatitis (NASH). Glucagon-like peptide-1 (GLP-1) analogues are licensed for type 2 diabetes, but no prospective experimental data exists in NASH. This study determined the effect of a long-acting GLP-1 analogue, liraglutide, on organ-specific insulin sensitivity, hepatic lipid handling and adipose dysfunction in biopsy-proven NASH. METHODS: Fourteen patients were randomised to 1.8mg liraglutide or placebo for 12-weeks of the mechanistic component of a double-blind, randomised, placebo-controlled trial (ClinicalTrials.gov-NCT01237119). Patients underwent paired hyperinsulinaemic euglycaemic clamps, stable isotope tracers, adipose microdialysis and serum adipocytokine/metabolic profiling. In vitro isotope experiments on lipid flux were performed on primary human hepatocytes. RESULTS: Liraglutide reduced BMI (-1.9 vs. +0.04kg/m(2); p<0.001), HbA1c (-0.3 vs. +0.3%; p<0.01), cholesterol-LDL (-0.7 vs. +0.05mmol/L; p<0.01), ALT (-54 vs. -4.0IU/L; p<0.01) and serum leptin, adiponectin, and CCL-2 (all p<0.05). Liraglutide increased hepatic insulin sensitivity (-9.36 vs. -2.54% suppression of hepatic endogenous glucose production with low-dose insulin; p<0.05). Liraglutide increased adipose tissue insulin sensitivity enhancing the ability of insulin to suppress lipolysis both globally (-24.9 vs. +54.8pmol/L insulin required to ½ maximally suppress serum non-esterified fatty acids; p<0.05), and specifically within subcutaneous adipose tissue (p<0.05). In addition, liraglutide decreased hepatic de novo lipogenesis in vivo (-1.26 vs. +1.30%; p<0.05); a finding endorsed by the effect of GLP-1 receptor agonist on primary human hepatocytes (24.6% decrease in lipogenesis vs. untreated controls; p<0.01). CONCLUSIONS: Liraglutide reduces metabolic dysfunction, insulin resistance and lipotoxicity in the key metabolic organs in the pathogenesis of NASH. Liraglutide may offer the potential for a disease-modifying intervention in NASH.

COVID-19 and pulmonary Tubercuiosis coinfection: three case reports from Iran.

Tubercuiosis is still a significant problem worldwide. Until the COVID-19 pandemic, tuberculosis was the leading cause of mortality from a single infectious agent. Pulmonary Tubercuiosis patients are more tending to be co-infected with COVID-19 notably when they have a history of exposure. There are some case reports relating to pulmonary TB and COVID-19 coinfection but the information about TB and COVID-19 was still little. We report three coinfected patients. Case one and two were both middle-aged Iranian mans with history of opium addiction, case one presented with dyspnea and weakness and case two presented with progressive weakness. Case three was a healthy young man with history of progressive dyspnea, productive cough and hemoptysis. Case one and case three were improved. In conclusion, COVID-19 is still an important issue and can coexist with other lung infections such as Pulmonary Tubercuiosis, so we should be aware of the advancement of the Tubercuiosis epidemic after the COVID-19 pandemic.

Brucellar epididymo-orchitis: Symptoms, diagnosis, treatment and follow-up of 50 patients in Iran.

Introduction: Epididymo-orchitis (EO) is a disease of both the epididymis and ipsilateral testis. Brucellar epididymo-orchitis (BEO) is an uncommon localized infection of the testis and epididymis which occurs in about 2-14 % of all patients with brucellosis as a result of urine Brucella removal or due to blood-borne septic metastasis. Methods: Between January 2018 and June 2021, 50 patients with fever, chills, swelling, and pain of the testicle (testicles) were referred to our center. Two approaches were used for the treatment of brucellarepididymo-orchitis among these individuals. Intravenous Gentamicin and Doxycycline were used in seven cases, while Rifampicin was added to this combination for the remaining 43 patients. Intravenous Gentamicin was administered for 7 days and the other drugs were used for 45 days. All patients were followed up for six months by monitoring the symptoms and signs of the disease. Results: None of the patients had been diagnosed with brucellosis before referral to our clinic. 43 patients were successfully treated by. Intravenous Gentamicin, Doxycycline and Rifampicin, whereas seven patients were fully treated using. Intravenous Gentamicin and Doxycycline. The two therapeutic groups were hospitalized for 7.56 ± 3.45 (3-23) and 10.14 ± 1.77 (8-13) days, respectively. Treatment failure, drug side effects, and disease complications were not observed in any of the cases over a 6-month follow-up period. Conclusions: Physicians should be alert regarding Brucellarepididymo-orchitis (BEO) within the differential diagnosis of nonspecific epididymo-orchitis, especially in regions where the disease is endemic. Delay in diagnosis or inappropriate management of BEO may result in complications.

Glanders (Burkholderia mallei infection) in an Iranian man: A case report.

Background: Glanders is a rare disease that has been eradicated in many countries but may be difficult to diagnose due to its nonspecific symptoms. This disease, which can be highly fatal if left untreated, is caused by a bacterium called Burkholderia mallei. Humans can get the disease through contact with infected animals, such as horses. Over time, various treatment strategies have been proposed for this disease, and attempts haveeven been made to develop a vaccine, but thus far, no effective vaccine has been developed to prevent it. Case presentation: In this article, we describeacase of Glanders disease in KamkarArabnia Hospital in Qom, Iran. The patient was a 22-year-old man with headache, fever, chills, diarrhea, and vomiting of blood, and was admitted to the infectious ward in isolation. Conclusion: The lack of definitive diagnostic symptoms and the rarity of this disease make it difficult to diagnose, and one should be careful in dealing with its symptoms. Also, paying attention to the patient's medical history and travel history to endemic areas, can lead to timely diagnosis and treatment.

Investigating sentence processing and working memory in patients with mild Alzheimer and elderly people.

INTRODUCTION: Linguistic disorders are one of the common problems in Alzheimer's disease, which in recent years has been considered as one of the key parameters in the diagnosis of Alzheimer (AD). Given that changes in sentence processing and working memory and the relationship between these two activities may be a diagnostic parameter in the early and preclinical stages of AD, the present study examines the comprehension and production of sentences and working memory in AD patients and healthy aged people. METHODS: Twenty-five people with mild Alzheimer's and 25 healthy elderly people participated in the study. In this study, we used the digit span to evaluate working memory. Syntactic priming and sentence completion tasks in canonical and non-canonical conditions were used for evaluating sentence production. We administered sentence picture matching and cross-modal naming tasks to assess sentence comprehension. RESULTS: The results of the present study revealed that healthy elderly people and patients with mild Alzheimer's disease have a significant difference in comprehension of relative clause sentences (P <0.05). There was no significant difference between the two groups in comprehension of simple active, simple active with noun phrase and passive sentences (P> 0.05). They had a significant difference in auditory and visual reaction time (P <0.05). Also there was a significant difference between the two groups in syntactic priming and sentence completion tasks. However, in non-canonical condition of sentence completion, the difference between the two groups was not significant (P> 0.05). CONCLUSION: The results of the present study showed that the mean scores related to comprehension, production and working memory in people with mild Alzheimer's were lower than healthy aged people, which indicate sentence processing problems at this level of the disease. People with Alzheimer have difficulty comprehending and producing complex syntactic structures and have poorer performance in tasks that required more memory demands. It seems that the processing problems of these people are due to both working memory and language problems, which are not separate from each other and both are involved in.

Lower Urinary Tract Symptoms and Related Factors in Iranian Female Nurses.

Background: Lower Urinary Tract Symptom (LUTS) are common among female nurses. High levels of job stress in nurses may be associated with the prevalence of these symptoms. This study aimed to investigate the prevalence of LUTS and factors related to these symptoms in female nurses. Materials and Methods: A cross-sectional study in which 460 nurses and nursing assistants participated was conducted. A questionnaire consisting of socio-demographic data, International Consultation on Incontinence Questionnaire - Female Lower Urinary Tract Symptoms, and Toileting Behavior - Women's Elimination Behavior Scale was used. Data analysis was performed by descriptive and inferential statistical tests at a significant level of p < 0.05. Results: The highest and lowest scores of LUTS were related to the urgency and nocturnal enuresis with a mean (SD) score of 1.85 (1.03) and 0.05 (0.26), respectively. Concerning toileting behaviors, the highest score was for the place preference for voiding with a mean (SD) score of 4.13 (0.66), which correlated with LUTS. Among controllable variables, years of practice, urinary tract infections, use of perineal pads for urinary leakage, lifting heavy objects at work, and medical history were identified as predictors of LUTS (p < 0.05). Conclusions: LUTS was highly prevalent in the female nurses. The results revealed that unhealthy toileting behaviors may contribute to the prevalence of LUTS. Early identification of these symptoms and the development of an educational intervention program to enhance the knowledge of healthy toileting behaviors may prevent the occurrence of urinary symptoms.

Community- and Health Care-Associated Methicillin-Resistant Staphylococcus aureus Infection in Tehran, Iran: Comparison of Drug Resistance and Virulence Determinants.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) can cause serious infections not only in hospitals but also in the community. The present study was aimed to characterize drug resistance and virulence determinants of community-associated (CA) MRSA isolate compared with healthcare-associated (HA) MRSA. MATERIALS AND METHODS: A total of 44 patients with HA-MRSA and 11 patients with CA-MRSA infection (median age, 72 years) were included. The clinical isolates of MRSA were subjected to molecular analysis of virulence genes and drug susceptibility testing. RESULTS: Panton-Valentine leucocidin (PVL) exotoxin and toxic shock syndrome toxin (TSST) genes were disproportionately distributed between CA- and HA-isolates. PVL genes were more likely to be found among CA-isolates (36.4%) than HA-isolates (18.2). TSST genes were identified in only 2 CA-MRSA isolates tested (18.2%) compared with 9 HA-isolates (20.5%). Exfoliative toxin- b gene was negative in all isolates, however, one HA-isolate was positive for exfoliative toxin-a. mec-A gene was present in all clinical isolates. CA-isolates were more likely to be susceptible to trimethoprim-sulfamethoxazole and vancomycin compared with HA-isolates. Vancomycin-intermediate resistance was found in 2 HA-isolates. All clinical isolates were also resistant to clindamycin. CONCLUSION: CA- and HA- MRSA isolates are epidemiologically and microbiologically distinct. Thus, the strategies to prevent and treat these infections would be different. Patients with CA- and HA-MRSA infections should be treated effectively and receive follow-up evaluation to ensure the resolution of their infection. Surveillance studies should be conducted to determine the extent of CA- and HA-MRSA dissemination in Iran.

The Probable Association between Blood Groups and Prognosis of COVID-19.

BACKGROUND: We aimed to verify the association between blood group systems and prognosis of SARS-Cov-2 disease. METHODS: In this cross-sectional study, 329 patients infected with SARS-Cov-2 diagnosed based on their COVID-19 RT-PCR results and chest CT scans, were enrolled in the study. These patients were admitted to Kamkar Arab Nia Hospital, Qom, Iran from March to June 2020. Their blood groups and RH were determined, and demographic characteristics and clinical signs of patients were recorded. The patients' temperature and peripheral capillary oxygen saturation levels (SpO2) were measured. Finally, the duration of hospitalization, intubation, and death rate were also analyzed. RESULTS: The results of the patients' blood group analysis were as follows: 129(39.2%) patients had A type, 66(20.1%) B type, 21(6.4%) AB type, and 113(34.3%) O type. Of 329 patients, 297 (90.3%) had Rh antigen. The dead cases were higher in O blood type at 13 cases (11.5%). Considering the positive and negative rhesus antigen, 31 (10.4%) and 1 (3.1%) were dead respectively, but the difference was not statically significant. As for the A group, the mean of admission duration (8.4±6.1 days) was not significantly different from the B group (8.8 ±7.2 days). AB group with a mean (7.4 ±4.4 days) was not significantly different from the O group (7.8 ± 5.4 days). There was no significant difference in the duration of hospitalization in RH patients, positive or negative. B blood group showed a significant association with the time interval to return to normal oxygen levels. CONCLUSION: Blood type was not associated with COVID-19 death rate, nor was it associated with admission duration. B blood group showed a significant association with the time interval to return to normal oxygen levels.

Does vitamin D serum level affect prognosis of COVID-19 patients?

BACKGROUND: Since the beginning of the Coronavirus disease 2019 (COVID-19) pandemic there have been contradictions and speculations about the relationship between vitamin D and COVID-19. Given that there is an association between vitamin D deficiency and some diseases - including cancer, autoimmune disease and some infectious diseases - a higher incidence and mortality rate in the vitamin-D-deficient COVID-19 population was not a surprise; conversely, some research would argue this relationship. Considering these contradictions, this study aimed to determine the relationship between prognosis and vitamin D level in cases with COVID-19. METHODS: In this cross-sectional study, 329 confirmed cases of COVID-19 - who were admitted to Kamkar-ArabNia Hospital in Qom city, Iran from March-July 2020 - were categorized into three groups according to vitamin D serum levels (ng/ml): sufficient (>30), insufficient (20-30) and deficient (<20). Prognosis was determined across the groups. RESULTS: There was a significant difference in hospital stay between patients with sufficient and insufficient vitamin D levels (P = 0.007). Adjusting vitamin D levels for confounding variables, linear regression underscored significant differences in the association between length of hospitalization and lower vitamin D levels, with a longer stay noted in insufficient groups (P = 0.002). However, there was no significant difference in the time interval to return to normal oxygen level (from SpO2 < 93%) or death rate between groups (P > 0.05). CONCLUSION: There was a significant association between hospital stay and lower serum vitamin D levels. However, the relationship between vitamin D status and death rate or the time interval to return to normal oxygen levels was not significant.

Organophosphorus pesticides extraction with polyvinyl alcohol coated magnetic graphene oxide particles and analysis by gas chromatography-mass spectrometry: Application to apple juice and environmental water.

In this study, we synthesized, characterized the magnetic graphene oxide coated with polyvinyl alcohol (PVA@MGO), and used it as an adsorbent for the magnetic solid-phase extraction (MSPE) of organophosphorus pesticides (OPPs) residue in the apple juice and environmental water samples followed by gas chromatography-mass spectrometry (GC-MS) analysis. Effective factors on the extraction efficiency, including the adsorbent dosage, desorption conditions, sample pH, extraction and desorption time, and ionic strength were optimized. The dynamic range of the MSPE-GC-MS method was obtained in the concentration range of 0.07-500 ng mL-1 OPPs with the limits of detection (LODs) in the range of 20-80 pg mL-1. Also, the intra- and inter-day precisions were determined to be in the range of 3.3-5.7% and 5.9-8.2%. The relative recoveries of pesticides for spiked real water samples and apple juice were in the range of 94.5 and 107.1%, with relative standard deviations between 2.6 and 6.5%. These results propose that the PVA@MGO is appropriate for simultaneous determination and high throughput analysis of OPPs residues.

Effect of teledentistry on the oral health status of patients undergoing fixed orthodontic treatment at the first three follow-up visits.

BACKGROUND: As the prevalence of such oral diseases as dental caries and periodontal problems increases during fixed orthodontic treatment, patient education is an essential aspect of any such treatment. Two methods have been proposed for this purpose: direct education in a clinic (the conventional method); and education using social media, such as the Telegram application (a type of teledentistry). OBJECTIVES: The aim of this study was to evaluate the effect of teledentistry as an educational tool on the oral health status of patients undergoing fixed orthodontic treatment at the first 3 follow-up visits. MATERIAL AND METHODS: Sixty participants were enrolled from patients whose fixed orthodontic treatment was to begin at a dental clinic in Tehran, Iran. They were randomly assigned to one of 2 trial arms. At the end of the 1st appointment, one of the groups was educated in person about maintaining oral hygiene during treatment, and an educational clip was sent to the members of the other group via the Telegram application. During the next 3 follow-up appointments, plaque index (PI), bleeding on probing (BOP), and gingival color and consistency were analyzed for each patient to assess their oral hygiene compliance during treatment. RESULTS: There was a statistically significant difference in PI and BOP between the 2 groups at the 3rd and 4th appointments; however, gingival color and consistency did not differ significantly with regard to the manner of education (p > 0.05). Patient age did not have a considerable effect on the oral health status in either group (p > 0.05). CONCLUSIONS: Teledentistry is an effective and efficient method to improve oral hygiene in patients undergoing fixed orthodontic treatment.

The COVID-19 Outbreak in Iran; The First Patient with a Definite Diagnosis.

The novel coronavirus, formerly named as 2019 novel coronavirus (2019-nCov) caused a rapidly spreading epidemic of severe acute respiratory syndrome (SARS) in Wuhan, China and thereafter, progressed globally to form a pandemic of coronavirus disease 2019 (COVID-19) in numerous countries; and now confirmed cases are reported from several provinces of Iran. Now various medical centers, clinicians and researchers around the world share their data and experiences about COVID-19 in order to participate in the global attempt of controlling the pandemic. The current report investigates the clinical presentations and paraclinical findings of the first confirmed cases and mortalities in the initiation of the outbreak of COVID-19 in Iran.

Effect of 0.05% Sodium Fluoride Mouthwash on Surface Roughness and Friction between Ceramic Brackets and Rhodium-Coated and Uncoated Stainless Steel Wires.

OBJECTIVES: This study aimed to assess the effect of 0.05% sodium fluoride (NaF) mouthwash on the surface roughness and friction between ceramic brackets and rhodium-coated (RC) and uncoated stainless steel (SS) wires. MATERIALS AND METHODS: This experimental study was performed on 48 maxillary premolar ceramic brackets. Twenty-four pieces of RC-SS wires were used. Samples were divided into four groups. Groups 1 and 2 were immersed in artificial saliva, and groups 3 and 4 were immersed in a solution consisting of artificial saliva (9%) and mouthwash (91%). To assess surface roughness, images were obtained from the surface of wires and brackets with atomic force microscopy (AFM) and scanning electron microscopy (SEM) before and after the intervention. To assess friction, the wires were ligated into brackets, and friction was measured at a crosshead speed of 0.5 mm/minute using a universal testing machine. Data were analyzed using one-way analysis of variance (ANOVA) at the 0.05 significance level. RESULTS: Friction during sliding in RC wires was significantly less than that in SS wires (P<0.05). Increase in the friction in SS wires by mouthwash was significantly greater compared to RC wires (P<0.05). Surface roughness coefficients of the wires before the intervention were not significantly different. The surface roughness of the wires significantly increased after the intervention and it was greater in SS wires than in RC wires (P<0.05). CONCLUSION: Considering the lower friction and surface roughness of SS-RC wires compared to SS wires, SS-RC wires may be a better alternative for use with ceramic brackets.

Evaluation of the Shear Bond Strength and Adhesive Remnant Index in Debonding of Stainless Steel Brackets Assisted with Nd:YAG Laser Irradiation.

OBJECTIVES: The purpose was to compare shear bond strength (SBS), pulp temperature, and adhesive remnant index (ARI) in debonding of stainless steel brackets from enamel surface using neodymium-doped yttrium aluminum garnet (Nd:YAG) laser versus the conventional debonding method. MATERIALS AND METHODS: Forty-eight extracted premolars were bonded to stainless steel brackets. The samples were divided into three experimental groups and one control group. In the first three groups, Nd:YAG laser was used for debonding with the power of 1, 1.5, and 2 W, respectively, for 10 seconds. The SBS and ARI of the samples were assessed. Pulp temperature was recorded before and after irradiation. Two samples from each group were used for determining enamel morphology after debonding using scanning electron microscopy (SEM). RESULTS: The mean SBS in the groups was 33.05, 28.69, 24.37, and 31.53 MPa, respectively, with no statistically significant differences (P=0.205). Significant differences in post-irradiation temperature were noted among the lased groups (P=0.000). Debonding mainly occurred at the adhesive-enamel interface in the 1-W laser and control groups and at the bracket-adhesive interface in the 1.5-W and 2-W laser groups. Enamel structure was amorphous and irregular following laser irradiation. CONCLUSION: Based on the results of this study, the use of Nd:YAG laser could not significantly affect the SBS. Therefore, this laser would not be suitable for debonding of metal brackets. The use of a 2-W laser could significantly raise the pulpal temperature. Nd:YAG laser renders a more heterogeneous enamel morphology compared to conventional debonding methods.

Two-Dimensional Analysis of the Size of Nasopharynx and Adenoids in Non-Syndromic Unilateral Cleft Lip and Palate Patients Using Lateral Cephalograms.

OBJECTIVES: Cleft lip and palate (CLP) is the most common congenital anomaly of the head and neck region. The upper airway in CLP patients is affected by retarded maxillary growth. Small size of the nasopharynx can also lead to mouth breathing. This study aimed to compare the size of nasopharynx and adenoids in non-syndromic unilateral CLP (NSUCLP) patients and healthy controls two-dimensionally on lateral cephalograms. MATERIALS AND METHODS: This retrospective study was performed on 30 children with NSUCLP (mean age of 11.3 years) and 30 sex- and age-matched healthy controls with class I skeletal relationship. The bony boundaries of the nasopharynx, nasopharyngeal airway and adenoids were outlined on lateral cephalograms and their surface area was calculated and compared between the two groups. The percentage of nasopharynx occupied by the adenoids was calculated for each individual and compared between the two groups using independent t-test. RESULTS: Size of nasopharynx in NSUCLP children was significantly smaller than that in healthy controls (P=0.0001). Size of adenoids was significantly larger in NSUCLP children (P=0.0001). Size of nasopharyngeal airway was smaller in NSUCLP patients than controls (P=0.0001). Percentage of nasopharynx occupied by the adenoids was significantly greater in NSUCLP patients (P=0.0001). CONCLUSIONS: The size of nasopharynx is smaller while the size of adenoids is larger in NSUCLP children compared to healthy controls; this can lead to mouth breathing and velopharyngeal incompetence.

Comparison of Enamel Morphologic Characteristics after Conditioning with Various Combinations of Acid Etchant and Er:YAG Laser in Bonding and Rebonding Procedures: A SEM Analysis.

OBJECTIVES: Many studies have evaluated re-etched enamel by using scanning electron microscopy (SEM); however, there is no evidence regarding the use of Erbium-doped yttrium aluminium garnet (Er:YAG) laser at primary and secondary bonding instead of acid etching with regards to enamel surface changes. The purpose of the present study was to determine that whether or not the methods of primary and secondary enamel preparation affect enamel characteristics after rebonding, by using SEM analysis. MATERIALS AND METHODS: Twelve freshly extracted premolars were divided into 4 groups. The samples in each group were conditioned by acid etchant or Er:YAG laser at primary conditioning, according to the instructions. Afterwards, they were bonded with orthodontic brackets. After debonding, the samples were prepared for second conditioning. Also, two samples were conditioned only once with acid etchant or laser, to compare enamel morphology changes with those after re-etching. Finally, buccal enamel surfaces were evaluated using SEM. RESULTS: Enamel etching patterns were observed in the samples which had been acid-conditioned at first or at both conditionings. The samples irradiated by Er:YAG laser showed amorphous and irregular surfaces, with no signs of typical etching patterns. A large deep gap was seen in one of the samples irradiated with laser at primary and secondary conditionings, which might have penetrated the underling layers of enamel and dentin. CONCLUSIONS: Enamel surface preparation with Er:YAG laser produces irregular and indistinct morphologic changes, completely different from those produced after acid etching at both conditioning and reconditioning. Therefore, it is recommended to use this laser with caution to avoid permanent enamel damage.