Requirements for the containment of COVID-19 disease outbreaks through periodic testing, isolation, and quarantine

We employ individual-based Monte Carlo computer simulations of a stochastic SEIR model variant on a two-dimensional Newman-Watts small-world network to investigate the control of epidemic outbreaks through periodic testing and isolation of infectious individuals, and subsequent quarantine of their immediate contacts. Using disease parameters informed by the COVID-19 pandemic, we investigate the effects of various crucial mitigation features on the epidemic spreading: fraction of the infectious population that is identifiable through the tests; testing frequency; time delay between testing and isolation of positively tested individuals; and the further time delay until quarantining their contacts as well as the quarantine duration. We thus determine the required ranges for these intervention parameters to yield effective control of the disease through both considerable delaying the epidemic peak and massively reducing the total number of sustained infections.

No Association between Clinical Periodontal Conditions and Microbiological Findings on Driveline of Patients with Left-Ventricular Assist Devices (LVAD)

The aim of this retrospective study was to investigate whether there would be an association between periodontal disease parameters and positive bacterial findings at the driveline of patients with a left ventricular assist device (LVAD). Patients with an LVAD, who underwent a full oral and microbiological examination between 2016 and 2018, were included. During oral examination, periodontitis severity (stage and grade) and the periodontal inflamed surface area (PISA) were evaluated. A microbiological analysis was performed from swabs of the driveline, whereby different bacterial species were cultivated and analyzed. A total of 73 patients were included in the current study. The majority of participants (80.8%) had at least one positive bacterial finding during the study period. Most patients had a periodontitis stage of III-IV (80.9%). The determined PISA of the total group was 284.78 ± 352.29 mm². No associations were found between the periodontal disease parameters and the bacterial findings in general, the bacterial findings on the day of oral examination or the bacterial findings 12 months prior to/after the oral examination (p > 0.05). Periodontitis is not associated with cultivated microbiological findings at the driveline of patients with an LVAD and thus appears not to be a risk indicator for driveline colonization. Nevertheless, the high periodontal burden in LVAD patients underlines the need for their improved periodontal care.

Biological control of Golovinomyces cichoracearum, the causal pathogen of sunflower powdery mildew

Background Powdery mildew was found in most of the sunflower fields in Egypt, causing severe yellowing of the blade, petiole, stem and calyx, as well as a considerable defoliation during the summer season of 2018. Out of the fungal mycelium from infected leaves, collected from sunflower fields in the four Egyptian Governorates (Kafr El-Sheikh, Gharbia, Giza and El-Beheira), five isolates of powdery mildew pathogen were obtained and identified using morphological and molecular identification methods. Results In 2019 and 2020 seasons, five biocontrol agents (Bacillus subtilis, B. pumilus, Trichoderma harzianum, T. viride and T. koningii) were used to control powdery mildew disease on sunflower plants under field conditions compared with the fungicide (Vectra 10% SC). Treatments were significantly effective for controlling the powdery mildew disease relative to the control. The best treatment for reducing disease parameters (final disease severity (FDS%), area under disease progress curve (AUDPC) and efficacy) than the control was T. koningii. Foliar application of all the tested treatments improved plant height, head and stem diameters and seed yield in relation to untreated plants (control). The components (FDS%, AUDPC and efficacy) were extracted and described approximately 95.251% of the pooled data of seasons 2019 and 2020. In such pooled data, the principal components (PC1, PC2 and PC3) of all disease parameters, plant development parameters and yield components were recorded 76.305, 86.635 and 96.265% of the total variance, respectively. Conclusion A biological control agent, such as T. koningii, can be suggested for disease control based on the experimental findings.

Anti-IL-6 cytokine treatment has no impact on elevated hematocrit and splenomegaly in a polycythemia vera mouse model

Somatic mutations in JAK2, MPL and Calreticulin and inflammation play a key role in pathophysiology of chronic myeloproliferative neoplasia (CMN). One of the most prominent cytokines elevated in serum of Polycythemia vera patients is interleukin-6 (IL-6). Currently, it is being discussed whether suppression of inflammation by anti-cytokine approaches as anti-IL-6 treatment may be therapeutically useful in CMN. We here sought to investigate the efficacy of anti-IL-6 treatment on inflammatory cytokines, hematocrit and splenomegaly in CMN like disease. JAK2-V617F knock-in mice (JAK2+/V617F) were treated for three weeks with anti-IL-6 antibody (Ab) or IgG-control. Upon anti-IL-6 Ab treatment, serum levels of CXCL2 and CXCL10 were significantly reduced. In addition, CXCL1, CCL11, M-CSF, G-CSF, IL-17, IL-12p40 and CCL2 were reduced by a factor of 0.3 - 0.8. Partly, this was also achieved by applying high-dose IgG. Hematocrit, erythrocyte and leukocyte counts were elevated in JAK2+/V617F mice but were not reduced by anti-IL6 Ab treatment. In addition, there was no apparent amelioration of splenomegaly and spleen histopathology. In conclusion, anti-IL-6 Ab treatment did not result in improvement of hematological disease parameters but was shown to modulate the serum cytokine signature.

Proposing a surgical algorithm for graduated orbital decompression in patients with Graves’ orbitopathy

Purpose To determine the outcome after orbital decompression using a graduated technique, adapting the surgical technique according to individual patients’ disease characteristics. Methods We retrospectively examined the postoperative outcome in patients treated with a graduated balanced orbital decompression regarding reduction of proptosis, new onset diplopia and improvement in visual function. 542 patients (1018 orbits) were treated between 2012 and 2020 and included in the study. Clinical examinations including visual acuity, exophthalmometry (Hertel) and orthoptic evaluation were performed preoperatively and at minimum 6 weeks postoperatively. Mean follow-up was 22.9 weeks. Results Mean proptosis values have significantly decreased after surgery (p < 0.01). In 83.3% of the patients Hertel measurement normalized (≤ 18 mm) after surgery, New onset diplopia within 20° of primary position occurred in 33.0% of patients, of whom 16.0% had preoperative double vision in secondary gaze. Patients suffering from dysthyroid optic neuropathy (DON) had a significant increase in visual acuity (p < 0.01). Conclusion We demonstrated that individually adapted graduated orbital decompression successfully improves key disease parameters of Graves’ orbitopathy with low morbidity.