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We introduce a model to describe the evolution of bacterial meningitis epidemics in a non-constant population. We derive the value of the basic reproduction number of our model. We analyze the local and global stability of the disease-free and endemic equilibria. We confirm the results by a numerical analysis of the model. [ABSTRACT FROM AUTHOR]

Background: Group B Streptococcus (GBS) transmitted from colonized pregnant women to the newborns is considered the leading cause of neonatal sepsis with high mortality rate, so screening pregnant women for GBS colonization is important for intrapartum antibiotic prophylaxis to prevent neonatal and maternal infections, this study aimed to detect the prevalence of GBS colonization in pregnant women and to assess the diagnostic value of GeneXpert PCR assay in screening. Methods: Rectovaginal swabs from 318 pregnant women with gestational age 35 or more weeks were tested by conventional culture as a standard screening method and by GeneXpert PCR assay as a rapid molecular method. Results: The prevalence of GBS colonization in pregnant women was 17% by standard culture method and 22% by the GeneXpert PCR assay with overall 98.2% sensitivity, 93.6% specificity, 94.3% diagnostic accuracy and total turnaround time less than 1 hour. Conclusion: The increase in prevalence of GBS colonization of pregnant women raises the concern about importance of the accurate and rapid molecular diagnostic techniques for effective prevention of GBS transmission. [ABSTRACT FROM AUTHOR]

Abstract Background Bone metastasis can be noted in the course of many primary malignant neoplastic lesions; breast and prostate cancers are the most frequent, but lung, kidney, and thyroid malignancies frequently metastasize to bones. Secondary osseous lymphomatous infiltrations is relatively uncommon and mainly noted in patients with non-Hodgkin lymphoma (NHL). By adding the metabolic changes to the conventional CT morphologic changes, combined positron emission tomography (PET) and computed tomography (CT) may offer clinically useful addition in assessment of treatment response of these lesions and offer helpful judgment for the different oncologic therapeutic regimens. Results The study included 45 patients, 24 females (53.33%) and 21 males (46.66%). Showing bone dominant or isolated bony secondary malignant infiltrations. The study included 24 patients with history of breast cancer (53.33%), 12 patients with history of lymphoma (26.66%), and 9 patients (20%) with history of lung cancer. All the bony lesions included in the study were multiple lesions in each patient, classified into mixed lytic and sclerotic bony lesions in 21 patients (46.66%), sclerotic lesions in 12 patients (26.66%), and radiologically occult lesions or osteopenic areas in 12 patients (26.66%). The most accurate SUV max cut-off value among studied cases was 4, taking the lesion with highest SUV max value as the reference standard, with measurements taken before and after the medical regimen with six months interval. Confirmation of PET/CT results was done by serial post management follow up at 6 months interval and 1 year interval. Conclusion PET/CT study is an effective tool for assessment of treatment response for ossoues secondary malignant lesions.

Abstract Background In December 2019, a large outbreak of a novel coronavirus infection occurred in Wuhan, China. The pneumonic disease caused by this virus is called coronavirus disease 2019 (COVID-19) by the World Health Organization (WHO). As case numbers have increased worldwide, gastro-intestinal symptoms like diarrhea, constipation, abdominal pain, and vomiting have been increased, these symptoms associated with positive laboratory results including abnormal liver function tests, renal function tests, and D-Dimer levels. Although there are multiple articles evaluated the imaging findings in HRCT of COVID-19 patients that helped in understanding the disease course and potential complications in the chest, yet there are—to our knowledge—limited data about the abdominal imaging findings of the course and potential abdominal complications of COVID-19 notably in the intensive care units (ICU). Results Forty-one sonographic examinations were done for 30 confirmed COVID-intensive care patients presented with abdominal symptoms. Of the 30 patients, 26 were males (86.66%), and 4 were females (13.3%), the average age of the patients was 57.7 years old. The most common sonographic observation was hepatomegaly (n, 23/41, 56%) and biliary system disease (n, 17/41, 41.4%); the imaging findings were correlated with the clinical and laboratory data. CT examination when indicated (in our study to assess hematomas for active extravasation and to assess bowel obstruction and its level). Conclusion Abdominal sonographic imaging was often performed for inpatients with COVID-19. Hepatobiliary dysfunction as well as nephropathy was the most common imaging findings.

Abstract Background Lymphoid neoplasms that present with masses are broadly referred to as lymphomas, and they can be classified to two main groups: Hodgkin’s (HL) and non-Hodgkin’s lymphoma (NHL); they are mainly characterized by enlargement of lymph nodes (nodal disease) although any organ in the body can be involved in different settings of the disease (extranodal disease). Adequate staging, which has a direct impact on prognosis, is essential to properly plan therapy. Stage IV disease with extranodal dissemination should be treated by long-term systemic chemotherapy. By adding the metabolic changes to the conventional CT morphologic changes, combined positron emission tomography (PET) and computed tomography (CT) may offer clinically useful addition in staging of lymphomas and detection of extranodal lesions. Results The study included thirty nine patients, with forty-eight extranodal sites with lymphomatous infiltration, twenty-four males (61.5%), and fifteen females (38.4%). The patients showed forty-eight extranodal abdominal lymphomatous infiltration. The study included twelve gastric lymphomatous lesions (25%), twelve splenic lymphomatous lesion (25%), three ileo-caecal lymphomatous lesions (6.25%), three patients (6.25%) with skin infiltration, three adrenal lymphomatous lesions (6.25%), three patients with hepatic lymphoma, and twelve bone marrow infiltrations (25%). The most accurate SUV max cutoff value among studied cases was 3.5, the highest SUV max value noted was 21 in gastric lesions, and the lowest SUV max noted was 4.1 in adrenal lesions. Confirmation of PET/CT results was done by histopathological assessment and post-management follow-up. Conclusion PET/CT study is an effective tool for evaluation of extranodal lymphomas. PET/CT fusion images can affect the clinical management plan by detection of extranodal lymphomas with lymphoma staging modification.

Abstract Background Injectable fillers are currently widely used in the clinical practice; there are many indications for injectable fillers including facial and gluteal rejuvenation, management of post-traumatic facial disfiguring, and pathological volumetric loss secondary to certain disease medications like human immune deficiency virus (HIV) medications. Radiologists should be familiar with the specific imaging features of the injectable fillers, characteristic anatomical locations, and possible complications to avoid diagnostic pitfalls especially when incidentally discovered while imaging of other pathological process like neoplastic work up or granulomatous lesions follow-up. Results The study included 48 patients (45 females and 3 males): 44 patients with facial injectable fillers and four patients with pelvic injectable fillers. Of the 48 patients, 37 patients showed unremarkable fillers features with normal morphological features and anatomical distribution, and eleven patients showed complications: six patients showed one complication, and five patients showed more than one complications. Dedicated fillers imaging study was done in 22 patients, while in the other 26 patients, imaging was done for other reasons, and fillers were notified and documented. Magnetic resonance imaging (MRI) was done for 46 patients; two patients were subjected to combine ultra-sonographic and CT examinations with no clinical indication for MRI study assessment. Conclusion Magnetic resonance imaging (MRI) is an effective tool for evaluation of facial and gluteal region fillers with delineation of their imaging features and related potential complications. Differentiation between fillers and neoplastic or granulomatous lesions could be accurately done with MRI.

Abstract Background Rectal cancer is a common malignancy that continues to have a highly variable outcome. Local pelvic recurrence following surgery is usually leading to incurable disease. Surgical resection with stage-appropriate combined-modality therapy is the mainstay in the treatment of rectal cancer. A difficulty has been reported in distinguishing the benign post-management findings from tumor recurrence. By adding the metabolic changes to the post-operative morphologic changes, combined positron emission tomography (PET) and computed tomography (CT) may offer clinically useful addition in operative bed evaluation. Results The study included 30 patients, 17 males (56.6%) and 13 females (43.3%). Suspicious operative bed findings included pre-sacral soft tissue density noted in 20 patients (66%), anastomotic site mural thickening in five patients (16.6%), and post-operative loco-regional nodes in five patients (16.6%). Moreover, pre-sacral soft tissue focal avid uptake was noted in 17 patients (17/20, 85%), and no uptake noted in three patients (3/20, 15%). Anastomotic site mural thickening was seen in five patients with positive uptake noted in three patients (3/5, 60%), and no uptake seen in two patients (2/5, 40%). Loco-regional nodes were seen in five patients with positive uptake in five patients. The most accurate SUV max cut-off value among studied cases was 3.5. Confirmation of PET/CT results was done by histopathological assessment in ten patients (33.3%) and by follow up after 6 months in 20 patients (66.6%) with recurrence noted in 15 patients (75%) and normal post-operative findings noted in five patients (25%). Conclusion PET/CT study is an effective tool for evaluation of suspicious colorectal oncologic operative bed findings noted in the routine CT studies. PET/CT fusion images affect the clinical management by guiding further procedures (surgery and radiation therapy).

Objectives: Pesticides are harmful to nature and therefore they are considered to be poisonous to the world. They have adverse effects on human health that include acute toxicity, cancer and endocrine systems, etc. Plants are a good alternative natural source for considering the negative impacts of conventional pesticides. Plant extracts are traditionally used to manage the insects. Methods: In the present study, the crude leaf extract of Solanum torvum (Sw.) was investigated for their preliminary phytochemical screening and their ability to protect the stored green grams from Callosobruchus maculatus (F.) adult infestation. The Solanum torvum (Sw.) ethyl acetate leaf extract was exhibited strong contact toxicity and repellent activity against Callosobruchus maculatus (F.) adult. The toxicity was significantly improved while extended treatment times and concentrations of Solanum torvum (Sw.). Results: The mean percentage of ethyl acetate leaf extract repellent value was reached 82% at the dose of 1500 ppm/cm2 after 1 h, followed by methanol (52%) and hexane (28%) leaf extract. The mortality was reached over the ethyl acetate leaf extract nearly 98% at the dose of 900 µg/cm2 after 72 h, followed by methanol (70%) and hexane (48%) leaf extract. Contact toxicity value of Solanum torvum (Sw.) leaf extract LC50 at 72 h interval was observed at 393.271 µg/mL, 632.338 µg/mL and 894.333 µg/mL for ethyl acetate, methanolic and hexane extract respectively against Callosobruchus maculatus (F.) adult. Conclusion: Thus the present study, Solanum torvum (Sw.) leaf extract could be useful for integrated pest management of Callosobruchus maculatus (F.) adult. The ethyl acetate leaf extract was shown good repellent and contact toxicity effect, followed by methanol and hexane extract. This method of natural plant extract can be used to control pests, alternate against the chemical insecticide.

Management of severe coronavirus disease 2019 requires advanced respiratory support modalities including invasive mechanical ventilation (IMV), continuous positive airway pressure (C-PAP), and non-invasive ventilation ((NIV). IMV leads to either subtle forms of lung injury (pulmonary edema, lung cysts) or more severe form of lung injury manifested as subcutaneous emphysema, pneumomediastinum, and pneumothorax (herein collectively termed barotrauma). We have described two cases showing the two end of spectrum of ventilator associated lung injury (VALI).

Rhizoctonia solani is a necrotrophic plant pathogen with a wide host range. R. solani is a species complex consisting of thirteen anastomosis groups (AGs) defined by compatibility of hyphal fusion reaction and subgroups based on cultural morphology. The relationship between such classifications and host specificity remains elusive. Here, we investigated the pathogenicity of seventeen R. solani isolates (AG-1 to 7) in Japan towards Arabidopsis thaliana using leaf and soil inoculations. The tested AGs, except AG-3 and AG-6, induced symptoms in both methods with variations in pathogenicity. The virulence levels differed even within the same AG and subgroup. Some isolates showed tissue-specific infection behavior. Thus, the AGs and their subgroups are suggested to be not enough to define the virulence (host and tissue specificity) of R. solani. We also evaluated the virulence of the isolates on Arabidopsis plants pretreated with salicylic acid, jasmonic acid, and ethylene. No obvious effects were detected on the symptom formation by the virulence isolates, but ethylene and salicylic acid slightly enhanced the susceptibility to the weak and nonvirulent isolates. R. solani seems to be able to overcome the induced defense by these phytohormones in the infection to Arabidopsis.

Mimosa pudica Linn is a well-known perennial herb and is traditionally used in ayurvedic medicine for the treatment of various illnesses. Despite its abundance in nature, the therapeutic potential of this invasive weed is deemed to be underappreciated in Malaysia. Previous studies have found an abundance of bioactive compounds associated with potent antioxidant properties in all parts of the plant. However, the optimum parameters required for the extraction of antioxidant compounds are still unknown. Therefore, the present study aimed to optimize the solvent extraction parameters of M. pudica using response surface methodology to enrich the accumulation of antioxidant compounds in the extracts. The effects of the optimized M. pudica extracts were then evaluated on the cell viability and glucose uptake ability in a 3T3-L1 adipocyte cell line. The highest total phenolic (91.98 mg of gallic acid equivalent per g of the dry extract) and total flavonoid content (606.31 mg of quercetin equivalent per g of the dry extract) were recorded when using 100% ethanol that was five-fold and three-fold higher, respectively, as compared to using 50% ethanol. The extract concentration required to achieve 50% of antioxidant activity (IC50 value) was 42.0 µg/mL using 100% ethanol as compared to 975.03 µg/mL using 50% ethanol. The results indicated that the use of 100% ethanol solvent had the greatest impact on the accumulation of antioxidant compounds in the extract (p < 0.05). Cell viability assay revealed that all extract concentration treatments recorded a viability level of above 50%. Glucose uptake assay using 2-NBDG analog showed that the cells treated with 50 µg/mL extract combined with insulin were five-fold higher than the control group. Given the high antioxidant and antidiabetic properties of this plant, M. pudica can be easily highlighted as a plant subject of interest, which warrants further investigation for nutraceutical prospects.

Rivers transport terrestrial microplastics (MP) to the marine system, demanding cost-effective and frequent monitoring, which is attainable through remote sensing. This study aims to develop and test microplastic concentration (MPC) models directly by satellite images and indirectly through suspended sediment concentration (SSC) as a proxy employing a neural network algorithm. These models relied upon high spatial (26 sites) and temporal (198 samples) SSC and MPC data in the Tisza River, along with optical and active sensor reflectance/backscattering. A feedforward MLP neural network was used to calibrate and validate the direct models employing k-fold cross-validation (five data folds) and the Optuna library for hyperparameter optimization. The spatiotemporal generalization capability of the developed models was assessed under various hydrological scenarios. The findings revealed that hydrology fundamentally influences the SSC and MPC. The indirect estimation method of MPC using SSC as a proxy demonstrated higher accuracy (R2 = 0.17–0.88) than the direct method (R2 = 0–0.2), due to the limitations of satellite sensors to directly estimate the very low MPCs in rivers. However, the estimation accuracy of the indirect method varied with lower accuracy (R2 = 0.17, RMSE = 12.9 item/m3 and MAE = 9.4 item/m3) during low stages and very high (R2 = 0.88, RMSE = 7.8 item/m3 and MAE = 10.8 item/m3) during floods. The worst estimates were achieved based on Sentinel-1. Although the accuracy of the MPC models is moderate, it still has practical applicability, especially during floods and employing proxy models. This study is one of the very initial attempts towards MPC quantification, thus more studies incorporating denser spatiotemporal data, additional water quality parameters, and surface roughness data are warranted to improve the estimation accuracy. [ABSTRACT FROM AUTHOR]