Automatic segmentation of kidneys in computed tomography images using U-Net.

PURPOSE: Accurate segmentation of target volumes and organs at risk from computed tomography (CT) images is essential for treatment planning in radiation therapy. The segmentation task is often done manually making it time-consuming. Besides, it is biased to the clinician experience and subject to inter-observer variability. Therefore, and due to the development of artificial intelligence tools and particularly deep learning (DL) algorithms, automatic segmentation has been proposed as an alternative. The purpose of this work is to use a DL-based method to segment the kidneys on CT images for radiotherapy treatment planning. MATERIALS AND METHODS: In this contribution, we used the CT scans of 20 patients. Segmentation of the kidneys was performed using the U-Net model. The Dice similarity coefficient (DSC), the Matthews correlation coefficient (MCC), the Hausdorff distance (HD), the sensitivity and the specificity were used to quantitatively evaluate this delineation. RESULTS: This model was able to segment the organs with a good accuracy. The obtained values of the used metrics for the kidneys segmentation, were presented. Our results were also compared to those obtained recently by other authors. CONCLUSION: Fully automated DL-based segmentation of CT images has the potential to improve both the speed and the accuracy of radiotherapy organs contouring.

Automatic segmentation of thoracic CT images using three deep learning models.

PURPOSE: Deep learning (DL) techniques are widely used in medical imaging and in particular for segmentation. Indeed, manual segmentation of organs at risk (OARs) is time-consuming and suffers from inter- and intra-observer segmentation variability. Image segmentation using DL has given very promising results. In this work, we present and compare the results of segmentation of OARs and a clinical target volume (CTV) in thoracic CT images using three DL models. MATERIALS AND METHODS: We used CT images of 52 patients with breast cancer from a public dataset. Automatic segmentation of the lungs, the heart and a CTV was performed using three models based on the U-Net architecture. Three metrics were used to quantify and compare the segmentation results obtained with these models: the Dice similarity coefficient (DSC), the Jaccard coefficient (J) and the Hausdorff distance (HD). RESULTS: The obtained values of DSC, J and HD were presented for each segmented organ and for the three models. Examples of automatic segmentation were presented and compared to the corresponding ground truth delineations. Our values were also compared to recent results obtained by other authors. CONCLUSION: The performance of three DL models was evaluated for the delineation of the lungs, the heart and a CTV. This study showed clearly that these 2D models based on the U-Net architecture can be used to delineate organs in CT images with a good performance compared to other models. Generally, the three models present similar performances. Using a dataset with more CT images, the three models should give better results.

Challenges and potential solutions in the development of COVID-19 pandemic control measures.

The coronavirus disease 2019 pandemic has become an unprecedented and major health concern all over the world. We discuss potential solutions and feasible strategies to reduce spread of infection and to develop disease control measures.

Challenges and accurate estimates of mortality and case-fatality rates due to COVID-19.

Many reasons restrict obtaining an accurate estimate of Case Fatality Rate (CFR) and Mortality Rate (MR) by COVID-19. The main concern is the number of infected people and deaths. We aimed to discuss some solutions for accurate estimating of CFR and MR.

Autotransplantation after primary bone repair of a recipient site with a large periradicular lesion: a case report.

AIM: To describe a case of autotransplantation nine weeks after the extraction of a hopeless tooth with a large periradicular lesion, which enabled the healing of the recipient site. SUMMARY: A 19-year-old male in generally good health was referred for evaluation of tooth 46. Clinically, there were class III mobility and sensitivity to percussion and palpation. There was a mesio-lingual swelling and a single narrow deep pocket of 15 mm at the disto-lingual aspect. CBCT imaging revealed a radiolucent area over 15 mm in diameter that extended from the mesial aspect of the mesial root of tooth 47 to the distal aspect of tooth 45. The radiolucent area was in proximity to the inferior alveolar canal and penetrated the buccal and the lingual cortical plates. The tooth was diagnosed with previously treated tooth, acute apical abscess and vertical root fracture. Tooth 46 was extracted, and a delicate curettage and drainage were performed. Nine weeks afterwards, a second surgery was performed: extraction of the impacted immature third molar (tooth 48). Immediately after the extraction, the tooth was replanted in the healing socket of tooth 46, and sufficient initial stability achieved. At a 1-year follow-up, the tooth had normal mobility, no sensitivity to palpation and percussion, and responded to thermal pulp testing. The soft tissue was normal, probing depths up to 3-mm, without swelling or sinus tract. Radiographically, periapical healing at the recipient site was observed. Compared to the post-operative periapical radiography immediately after the procedure, there was no change in the distal root dimensions. In the mesial root, development of the root length and a closed apex was demonstrated.

Sleep deprivation induces changes in 5-HT actions and 5-HT1A receptor expression in the rat hippocampus.

A 12h sleep deprivation enhances the expression of 5-hydroxytryptamine (5-HT) 1A receptors in rat hippocampus that recedes with 48h sleep recovery. The depressant effect of applied 5-HT on the field excitatory postsynaptic potentials recorded in the CA1 area, is also enhanced in hippocampi of SD rats. Following a 24 or 48h sleep recovery, the increase in the 5-HT effect subsided. These results have implications for therapeutics treating clinical depression.

New methods in the diagnosis of cancer and gene therapy of cancer based on nanoparticles.

Cancer is one of the leading cause of death in the world with the prevalence of >10 million mortalities annually. Current cancer treatments include surgical intervention, radiation, and taking chemotherapeutic drugs, which often kill the healthy cells and result in toxicity in patients. Therefore, researchers are looking for ways to be able to eliminate just cancerous cells. Intra-tumor heterogeneity of cancerous cells is the main obstacle on the way of an effective cancer treatment. However, better comprehension of molecular basis of tumor and the advent of new diagnostic technologies can help to improve the treatment of various cancers. Therefore, study of epigenetic changes, gene expression of cancerous cells and employing methods that enable us to correct or minimize these changes is critically important. In this paper, we will review the recent advanced strategies being used in the field of cancer research.

Silane crosslinking of electrospun poly (lactic acid)/nanocrystalline cellulose bionanocomposite.

Biodegradable nanofibrous mats fabricated by electrospinning are commonly used in tissue engineering, however, lack of essential mechanical properties of such nanofibers is a challenging issue. In this work, vinyltrimethoxysilane (VTMS) was grafted onto poly (lactic acid) (PLA) and the silane grafted PLA was subsequently applied in electrospinning process. Electrospun nanofibrous mats based on PLA/nanocrystalline cellulose (NCC) and PLA-g-silane/NCC nanocomposites were fabricated and immersed in hot water (70°C) for crosslinking of silane grafted PLA. It was found that introducing NCC to the samples cause to reduction in fiber diameter and the other hand the silane crosslinking of PLA increase the mean fiber diameter. DSC thermograms also revealed that silane grafting caused a reduction in mobility of polymer segments, and consequently reduction of crystallinity. On the contrary, the NCC in the PLA-g-silane samples effectively influenced the crystal nucleation, while in the PLA nanofibers the nucleation was lower. The impact of NCC on tensile strength enhancement of samples was notable. The results suggested that the chemical crosslinking remarkably improves the mechanical properties of PLA nanofibers. Furthermore, biocompatibility of such modified nanofibers was also evaluated through cytotoxicity results, therefore the modified PLA nanocomposite can be considered as a practical candidate for hard tissue engineering applications.

Coinhibition of overexpressed genes in acute myeloid leukemia subtype M2 by gold nanoparticles functionalized with five antisense oligonucleotides and one anti-CD33(+)/CD34(+) aptamer.

The aim of this study was to evaluate an engineered nanostructure to silence five important oncogenes, including BAG1, MDM2, Bcl-2, BIRC5 (survivin) and XIAP, in acute myeloid leukemia subtype 2 (AML-M2). The smart nanostructures were functionalized gold nanoparticles (FGNs) containing five antisense oligonucleotides (AOs) and one anti-CD33(+)/CD34(+) aptamer. First, the best AO for each gene was selected with the OligoWalk online software, and then different arrangements of AOs were evaluated with the RNAstructure software. Thereafter, naked gold nanoparticles (NGNs) were synthesized by the reaction of 1000 mm HAuCl4 with 10 µg ml(-1) ascorbic acid. Next, five AOs and one anti-CD33(+)/CD34(+) aptamer were attached to NGNs through serial reactions. Later, 5 ml of heparinized blood samples from five AML-M2 patients were prepared, cancerous cells were isolated and then incubated with three concentrations (75, 150 and 300 µg ml(-1)) each of FGNs, NGNs, gold nanoparticles functionalized with scrambled oligonucleotides (GNFSONs) and doxorubicin. Finally, cell death percentage and gene expressions were measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and real-time PCR, respectively. This study showed that FGNs and doxorubicin led to more cell death compared with NGNs and GNFSONs (P<0.05). Interestingly, all concentrations of FGNs led to a decrease in gene expression. As an important finding, although all concentrations of doxorubicin could also inhibit the expression of genes, FGNs had more effect (P<0.05). Moreover, both NGNs and GNFSONs could silence all genes only at a concentration of 300 µg ml(-1). For BCL2 and XIAP, a dose-dependent pattern was observed, but there was no similar pattern for others.

Effect of modified starch and nanoclay particles on biodegradability and mechanical properties of cross-linked poly lactic acid.

Mechanical properties and biodegradation of cross-linked poly(lactic acid) (PLA)/maleated thermoplastic starch (MTPS)/montmorillonite (MMT) nanocomposite were studied. Crosslinking was carried out by adding di-cumyl peroxide (DCP) in the presence of triallyl isocyanurate (TAIC) as coagent. At first, MTPS was prepared by grafting maleic anhydride (MA) to thermoplastic starch in internal mixer. Experimental design was performed by using Box-Behnken method at three variables: MTPS, nanoclay and TAIC at three levels. Results showed that increasing TAIC amount substantially increased the gel fraction, enhanced tensile strength, and caused a decrease in elongation at break. Biodegradation was prevented by increasing TAIC amount in nanocomposite. Increasing MTPS amount caused a slight increase in gel fraction and decreased the tensile strength of nanocomposite. Also, MTPS could increase the elongation at break of nanocomposite and improve the biodegradation. Nanoclay had no effect on the gel fraction, but it improved tensile strength.

Subclinical atherosclerosis in systemic lupus erythematosus patients and its relationship to disease activity and damage indices.

AIM OF THE WORK: To detect the incidence of premature atherosclerosis in systemic lupus erythematosus (SLE) patients and to study its association with disease activity and damage indices. PATIENTS AND METHODS: This study involved 50 adult female SLE patients with mean age 26.24 ± 8.63 years and mean disease duration 3.44 ± 4.01 years. The control group comprised 25 healthy adult females. All patients were subjected to a detailed clinical examination and laboratory investigations, and full case history was recorded. Assessment of disease activity was performed according to the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and disease damage was assessed using the Systemic Lupus International Collaborating Clinics (SLICC) score. B mode ultrasound was used to measure the intima-media wall thickness (IMT) and detect the presence of carotid plaques. RESULTS: In 15 patients (30 %), positive ultrasonographic findings represented by a significant increase in IMT (> 0.9 mm) could be shown; plaques were found in 3 of these patients (6 %). A significant difference was found between SLE patients and controls in terms of IMT (P < 0.0001). On subgrouping the SLE patients according to their IMT, there was a significant difference between those with thickened and normal IMT in terms of SLEDAI (P < 0.0001) and SLICC (p = 0.035) scores. CONCLUSION: Subclinical atherosclerosis is frequent in SLE patients. Increased disease activity and damage are associated with the occurrence of premature atherosclerosis.

Examining the effect of the CaMKII inhibitor administration in the locus coeruleus on the naloxone-precipitated morphine withdrawal signs in rats.

Drug addiction is an occurrence with physiological, psychological, and social outcomes. Repeated drug exposure causes neuronal adaptations and dependency. It has been shown that CaMKIIα enzyme contributes to morphine dependency. The locus coeruleus nucleus has been implied in the morphine withdrawal syndrome. This research focuses on the behavioral and molecular adaptations that occur in the locus coeruleus neurons in response to the chronic morphine exposure. Adult male Wistar rats were injected by morphine sulfate (10 mg/kg/s.c.) at an interval of 12 h for a period of nine subsequent days. On the tenth day, naloxone (1 mg/kg/i.p.) was injected 2 h after the morphine administration. Somatic withdrawal signs were investigated for 30 min. We concluded that the inhibition of CaMKIIα by administration of KN-93, the specific inhibitor of this enzyme, significantly attenuated some of the withdrawal signs. In molecular method, the expression of CaMKIIα protein has been enhanced in locus coeruleus of the morphine dependent rats. These findings indicate that CaMKIIα may be involved in the modulation of the naloxone-induced withdrawal syndrome, and treatment with KN-93 may have some effects on this system.

Pediculosis capitis among Primary School Children and Related Risk Factors in Urmia, the Main City of West Azarbaijan, Iran.

BACKGROUND: Pediculosis capitis is cosmopolitan health problem. In addition to its physical problems, its psychological effects especially on pupils are more important. This study was conducted to determine the Pediculosis capitis among primary school pupils and also find out the role of probable related risk factors in Urmia city, Iran 2010. METHODS: 35 primary schools of Urmia City according to the defined clusters randomly have been selected during 2010. 2040 pupils (866 boys and 1174 girls) were included and examined individually and privately by experts. Presence of adult or immature lice or having nits less than 1 cm from the hair basis were defined as positive. Data about demographic features and factors which their effect should be determined were recorded in standard questionnaire. Data were analyzed by SPSS software with proper statistical test. RESULTS: Infestation was determined around 4%. Girls show significantly greater infestation. The availability of suitable warm water for bathing and hair length (separately in girls and boys) are significantly related to infestation load as well as infestation among different age groups. There was no significant relation between parent's education and job and infestation as well as bathing repetition per week and the kind of energy source which they have. Also there is no significant correlation between educational grades and head lice infestation. CONCLUSION: The head louse pediculosis is a health problem and remains a health threatening for school children.Effective risk factors should be determined carefully and regionally. Proper training plays a great role in order to prevent and control the problem.

Development of an indirect ELISA test using a purified tachyzoite surface antigen SAG1 for sero-diagnosis of canine Toxoplasma gondii infection.

The aim of this study was to use affinity purified 30 kDa Toxoplasma gondii surface antigen (SAG1) in an indirect ELISA and to compare it with an existing indirect fluorescent antibody test (IFAT). 245 serum samples were collected from dogs from three adjacent Iranian provinces. IFAT examination revealed positive results in 73 dogs, with titers ranging from 1:16 to 1:1024. A suitable ELISA cut-off was determined by ROC analysis in comparison with IFAT. Results showed a relative sensitivity and specificity of 94.52% and 93.60%, respectively, for a cut-off value of 0.790 in the ELISA. No cross-reactivity was detected between antibodies against T. gondii and a closely related protozoan parasite, Neospora caninum, using this newly developed ELISA test.

Searching for virulence factors in the non-pathogenic parasite to humans Leishmania tarentolae.

Leishmania protozoa are obligate intracellular parasites that reside in the phagolysosome of host macrophages and cause a large spectrum of pathologies to humans known as leishmaniases. The outcome of the disease is highly dependent on the parasite species and on its ascribed virulence factors and the immune status of the host. Characterization of the genome composition of non-pathogenic species could ultimately open new horizons in Leishmania developmental biology and also the disease monitoring. Here, we provide evidence that the lizard non-pathogenic to humans Leishmania tarentolae species expresses an Amastin-like gene, cysteine protease B (CPB), lipophosphoglycan LPG3 and the leishmanolysin GP63, genes well-known for their potential role in the parasite virulence. These genes were expressed at levels comparable to those in L. major and L. infantum both at the level of mRNA and protein. Alignment of the L. tarentolae proteins with their counterparts in the pathogenic species demonstrated that the degree of similarity varied from 59% and 60% for Amastin, 89% for LPG3 and 71% and 68% for CPB, in L. major and L. infantum, respectively. Interestingly, the A2 gene, expressed specifically by the L. donovani complex which promotes visceralization, was absent in L. tarentolae. These findings suggest that the lack of pathogenicity in L. tarentolae is not associated with known virulence genes such as LPG3, CPB, GP63 and Amastin, and that other factors either unique to L. tarentolae or missing from this species may be responsible for the non-pathogenic potential of this lizard parasite.

[Acute diverticulitis of the appendix. A clinical case]. / Diverticolite acuta dell'appendice. Caso clinico.

The authors describe a case of acute diverticulitis of the appendix presenting as an inflammatory mass in the right lower quadrant of the abdomen. The histologic and clinical findings are discussed. This uncommon condition may mimic acute appendicitis, but in most instances it departs from typical appendicitis for later age of appearance, more indolent clinical course and increased tendency to perforation. In these cases the disease may progress with subacute interstitial inflammation, with or without abscess formation, and present as a tumor-like mass of the cecum.