33 research outputs found
Histopathologic Findings of Olfactory Mucosa in COVID-19 Patients
Background: Olfactory manifestations are common findings during the course of COVID-19, while exact physiopathology is not known
Aim: We review histological changes of the nasal olfactory mucosa in COVID-19 non-survivors who died in the ICU.
Methods: Sampling was done within 1 hour of death under direct vision. Specimens were taken medial to the middle turbinate in the cribriform area and embedded in paraffin blocks and stained by haematoxylin and eosin.
Results: The most frequent histologic finding was the infiltration of inflammatory cells mostly comprised of lymphocytes. Inflammatory infiltration of mucosa was seen in all 11 patients with ulceration in 9 cases and neuritis in 3 cases.
Conclusion: Inflammatory infiltration of olfactory mucosa may be associated with smell manifestations. Further histological studies will clarify the role of the nasal mucosa in the physiopathology of COVID-19 especially olfactory involvement
The potential of highly nutritious frozen stages of Tyrophagus putrescentiae as a supplemental food source for the predatory mite Amblyseius swirskii
Astigmatid mites have potential as supplementary prey items to support generalist predator populations in crops. However, applying living prey mites has some disadvantages; if not predated they have the potential to cause crop damage and allergies. In this study, we evaluated various diets based on the astigmatid mite Tyrophagous putrescentiae (Schrank) as a supplemental food source for the predatory mite Amblyseius swirskii Ahias-Henriot. Eggs and larvae of T. putrescentiae were reared on a diet of dog food (rich in proteins and fat) or bran (rich in carbohydrate); they were offered either frozen or alive, and either with or without cattail pollen (Typha angustifolia L.). Oviposition rate of A. swirskii fed with frozen mite larvae reared on dog food was similar to the rate observed when they were fed with cattail pollen or living prey mites, but developmental time of A. swirskii was longer on this frozen diet than on a diet of living prey mites or pollen. Both living and frozen prey mites were, in contrast with cattail pollen, not suitable for oviposition by western flower thrips, Frankliniella occidentalis Pergande. In a greenhouse study, the use of frozen prey mite stages as supplemental food on chrysanthemum plants allowed populations of A. swirskii to establish, but not increase; in contrast, provision of living prey mites and pollen increased A. swirskii populations on plants. Hence, our study shows that living prey mites, but not frozen prey mites, had the greatest potential as a supplemental food source for A. swirskii.</p
Experimental characterization of tool wear morphology and cutting force profile in dry and wet turning of titanium metal matrix composites (Ti-MMCs)
ABSTRACT: Metal-matrix composites (MMCs) are made of non-metallic reinforcements in metal matrixes, which have excellent hardness, corrosion, and wear resistance. They are also lightweight and may pose a higher strength-to-weight ratio as compared to commercial titanium alloys. One of the MMCs with remarkable mechanical properties are titanium metal matrix composites (Ti-MMCs), which are considered a replacement for super-alloys in many industrial products and industries. Limited machining and machinability studies of Ti-MMCs were reported under different cutting and lubrication conditions. Tool wear morphology and life are among the main machinability attributes with limited attention. Therefore, this study presents the effects of cutting and lubrication conditions on wear morphology in carbide inserts when turning Ti-MMCs. To that end, maximum flank wear (VB) and cutting forces were recorded, and the wear morphologies within the initial period of the cut, as well as the worn condition, were studied under dry and wet conditions. Experimental results denoted that despite the lubrication mode used, abrasion, diffusion, and adhesion mechanisms were the main wear modes observed. Moreover, built-up layer (BUL) and built-up edge (BUE) were the main phenomena observed that increase the tendency of adhesion at higher cutting times
Epidemiology of Psychiatric Disorders in Children and Adolescents in Chaharmahal and Bakhtiari Province, Iran, 2017
Background: This study aimed to investigate the epidemiology of psychiatric disorders in children and adolescents in Chaharmahal and Bakhtiari Province of Iran.
Methods: This community-based cross-sectional study included 1038 children and adolescents aged 6-18 years from Chaharmahal and Bakhtiari province selected by the multistage cluster sampling method. Samples were interviewed using the Schedule for Affective Disorders and Schizophrenia for School-Age Children. Also, demographic data (gender, age, child education, parent education, and economic situation) were obtained. Binary logistic regression was used to analyze the data.
Results: A total of 16.1% of participants were diagnosed to have psychiatric disorders. Total psychiatric disorders were significantly more prevalent in boys than in girls (P = 0.025). Unemployment of fathers was significantly related to increased prevalence of psychiatric disorders in children (P = 0.016). Other demographic variables had no significant correlation with prevalence of psychiatric disorders in children. Anxiety disorders were highly comorbid with behavioral problems (16.4%). Behavioral disorders also had high comorbidity with elimination disorders (16.7%) and substance use disorders (10%). Enuresis was the most frequent psychiatric disorder (5.8%), followed by epilepsy (3.5%), tobacco use (3.4%), and attention deficit hyperactivity disorder (3%). Total anxiety disorders were the most prevalent group of psychiatric disorders in the sample (21.9%), followed by behavioral disorders (16.3%), elimination disorders (8.2%), and neurodevelopmental disorders (4.5%).
Conclusion: Our findings suggest that psychiatric disorders affect a significant number of children and adolescents. Prevalence estimates and identification of sources of heterogeneity have important implications to service providers and modifications are needed in mental health services in the community
Prevalence and Correlates of Psychiatric Disorders in a National Survey of Iranian Children and Adolescents
Objective: Considering the impact of rapid sociocultural, political, and economical changes on societies and families, population-based surveys of mental disorders in different communities are needed to describe the magnitude of mental health problems and their disabling effects at the individual, familial, and societal levels.
Method: A population-based cross sectional survey (IRCAP project) of 30 532 children and adolescents between 6 and 18 years was conducted in all provinces of Iran using a multistage cluster sampling method. Data were collected by 250 clinical psychologists trained to use the validated Persian version of the semi-structured diagnostic interview Kiddie-Schedule for Affective Disorders and Schizophrenia-PL (K-SADS-PL).
Results: In this national epidemiological survey, 6209 out of 30 532 (22.31%) were diagnosed with at least one psychiatric disorder. The anxiety disorders (14.13%) and behavioral disorders (8.3%) had the highest prevalence, while eating disorders (0.13%) and psychotic symptoms (0.26%) had the lowest. The prevalence of psychiatric disorders was significantly lower in girls (OR = 0.85; 95% CI: 0.80-0.90), in those living in the rural area (OR = 0.80; 95% CI: 0.73-0.87), in those aged 15-18 years (OR = 0.92; 95% CI: 0.86-0.99), as well as that was significantly higher in those who had a parent suffering from mental disorders (OR = 1.96; 95% CI: 1.63-2.36 for mother and OR = 1.33; 95% CI: 1.07-1.66 for father) or physical illness (OR = 1.26; 95% CI: 1.17-1.35 for mother and OR = 1.19; 95% CI: 1.10-1.28 for father).
Conclusion: About one fifth of Iranian children and adolescents suffer from at least one psychiatric disorder. Therefore, we should give a greater priority to promoting mental health and public health, provide more accessible services and trainings, and reduce barriers to accessing existing services
Survey of CT radiation doses and iodinated contrast medium administration: an international multicentric study
ObjectiveTo assess the relationship between intravenous iodinated contrast media (ICM) administration usage and radiation doses for contrast-enhanced (CE) CT of head, chest, and abdomen-pelvis (AP) in international, multicenter settings. MethodsOur international (n = 16 countries), multicenter (n = 43 sites), and cross-sectional (ConRad) study had two parts. Part 1: Redcap survey with questions on information related to CT and ICM manufacturer/brand and respective protocols. Part 2: Information on 3,258 patients (18-96 years; M:F 1654:1604) who underwent CECT for a routine head (n = 456), chest (n = 528), AP (n = 599), head CT angiography (n = 539), pulmonary embolism (n = 599), and liver CT examinations (n = 537) at 43 sites across five continents. The following information was recorded: hospital name, patient age, gender, body mass index [BMI], clinical indications, scan parameters (number of scan phases, kV), IV-contrast information (concentration, volume, flow rate, and delay), and dose indices (CTDIvol and DLP). ResultsMost routine chest (58.4%) and AP (68.7%) CECT exams were performed with 2-4 scan phases with fixed scan delay (chest 71.4%; AP 79.8%, liver CECT 50.7%) following ICM administration. Most sites did not change kV across different patients and scan phases; most CECT protocols were performed at 120-140 kV (83%, 1979/2685). There were no significant differences between radiation doses for non-contrast (CTDIvol 24 [16-30] mGy; DLP 633 [414-702] mGycm) and post-contrast phases (22 [19-27] mGy; 648 [392-694] mGycm) (p = 0.142). Sites that used bolus tracking for chest and AP CECT had lower CTDIvol than sites with fixed scan delays (p < 0.001). There was no correlation between BMI and CTDIvol (r2 <= - 0.1 to 0.1, p = 0.931). ConclusionOur study demonstrates up to ten-fold variability in ICM injection protocols and radiation doses across different CT protocols. The study emphasizes the need for optimizing CT scanning and contrast protocols to reduce unnecessary contrast and radiation exposure to patients. Clinical relevance statementThe wide variability and lack of standardization of ICM media and radiation doses in CT protocols suggest the need for education and optimization of contrast usage and scan factors for optimizing image quality in CECT
CHEMICAL CONSTITUENTS AND TOXICITY OF ESSENTIAL OILS OF ORIENTAL ARBORVITAE, Platycladus orientalis (L.) FRANCO, AGAINST THREE STORED-PRODUCT BEETLES
Plant secondary metabolites play an important role in plant-insect
interactions and therefore such compounds may have insecticidal or
biological activity against insects. Fumigant toxicity of essential
oils of leaves and fruits from oriental arborvitae ( Platycladus
orientalis [L.] Franco) (Cupressaceae) was investigated against
adults of cowpea weevil ( Callosobruchus maculatus Fab.), rice weevil
( Sitophilus oryzae L.), and red flour beetle ( Tribolium castaneum
Herbst). Fresh leaves and fruits were subjected to hydrodistillation
using a Clevenger-type apparatus and the chemical composition of the
volatile oils was studied by gas chromatography-mass spectrometry
(GC-MS). Twenty-six compounds (92.9%) and 23 constituents (97.8%) were
identified in the leaf and the fruit oils, respectively. The major
components of both leaves and fruits oils were α-pinene (35.2%,
50.7%), α-cedrol (14.6%, 6.9%) and Δ-3-carene (6.3%, 13.8%),
respectively. Both oils in the same concentration were tested for their
fumigant toxicity on each species. Results showed that leaf oils were
more toxic than fruit oils against three species of insects.
Callosobruchus maculatus was more susceptible than S. oryzae and T.
castaneum. LC50 values of the leaf and the fruit oils at 24 h were
estimated 6.06 and 9.24 μL L-1 air for C. maculatus, 18.22 and
21.56 μL L-1 air for S. oryzae, and 32.07 and 36.58 μL L-1
air for T. castaneum, respectively. These results suggested that P.
orientalis oils may have potential as a control agent against C.
maculatus, S. oryzae, and T. castaneum