Periodic solutions for a model of tumor volume with anti-angiogenic periodic treatment

In this work, we consider the dynamics of a model for tumor volume growth under a drug periodic treatment targeting the process of angiogenesis within the vascularized cancer tissue. We give sufficient conditions for the existence and uniqueness of a global attractor consisting of a periodic solution. This conditions happen to be satisfied by values of the parameters tested for realistic experimental data. Numerical simulations are provided illustrating our findings.

3D Spheroid Formation Using BMP-Loaded Microparticles Enhances Odontoblastic Differentiation of Human Dental Pulp Stem Cells

Human dental pulp stem cells (hDPSCs) are the primary cells responsible for dentin regeneration. Typically, in order to allow for odontoblastic differentiation, hDPSCs are cultured over weeks with differentiation-inducing factors in a typical monolayered culture. However, monolayered cultures have significant drawbacks including inconsistent differentiation efficiency, require a higher BMP concentration than should be necessary, and require periodic treatment with BMPs for weeks to see results. To solve these problems, we developed a 3D-cell spheroid culture system for odontoblastic differentiation using microparticles with leaf-stacked structure (LSS), which allow for the sustained release of BMPs and adequate supply of oxygen in cell spheroids. BMPs were continuously released and maintained an effective concentration over 37 days. hDPSCs in the spheroid maintained their viability for 5 weeks, and the odontoblastic differentiation efficiency was increased significantly compared to monolayered cells. Finally, dentin-related features were detected in the spheroids containing BMPs-loaded microparticles after 5 weeks, suggesting that these hDPSC-LSS spheroids might be useful for dentin tissue regeneration.

Seasonal Treatment of an Infectious Disease is a Social Driver of Sustained Oscillations in the Disease incidence

We analyze a seasonal $SIR$ model that assumes a periodic treatment rate. Using the Leray-Schauder degree theory, we prove that model shows periodic solutions. This result shows that sustained oscillations in the incidence of the disease are related to the periodic application of a treatment against the disease. So, we can say that the periodic application of treatment can be considered a seasonal driver of the sustained oscillations.

Dynamic aspects of tumour–immune system interaction under a periodic immunotherapy

We study a mathematical model proposed in the literature with the aim of describing the interactions between tumor cells and the immune system, when a periodic treatment of immunotherapy is applied. Combining some techniques from non-linear analysis (degree theory, lower and upper solutions, and theory of free-homeomorphisms in the plane), we give a detailed global analysis of the model. We also observe that for certain therapies, the maximum level of aggressiveness of a cancer, for which the treatment works (or does not work), can be computed explicitly. We discuss some strategies for designing therapies. The mathematical analysis is completed with numerical results and conclusions.

Aedes aegypti miRNA-33 modulates permethrin induced toxicity by regulating VGSC transcripts

Aedes aegypti is a major vector of Zika, dengue, and other arboviruses. Permethrin adulticidal spraying, which targets the voltage-gated sodium channel (VGSC), is commonly done to reduce local mosquito populations and protect humans from exposure to arbovirus pathogens transmitted by this dangerous pest. Permethrin resistance, however, is a growing problem and understanding its underlying molecular basis may identify avenues to combat it. We identified a single G:C polymorphism in pre-miR-33 that was genetically associated with permethrin resistance; resulting isoforms had structural differences that may affect DICER-1/pre-miRNA processing rates. We then assessed the effects of overexpression of pre-miR-33 isoforms on permethrin toxicological phenotypes, VGSC transcript abundance and protein levels for two genetically related mosquito strains. One strain had its naturally high permethrin resistance levels maintained by periodic treatment, and the other was released from selection. VGSC protein levels were lower in the permethrin resistant strain than in the related permethrin-susceptible strain. Overexpression of the G-pre-miR-33 isoform reduced VGSC expression levels in both strains. To further elucidate changes in gene expression associated with permethrin resistance, exome-capture gDNA deep sequencing, genetic association mapping and subsequent gene set enrichment analysis revealed that transport genes, in particular, were selected in resistant versus susceptible mosquitoes. Collectively, these data indicate that miR-33 regulates VGSC expression as part of a nuanced system of neuronal regulation that contributes to a network of heritable features determining permethrin resistance.

Role of an Orthodontist in the Management of Cleft Maxilla With Anterior Maxillary Segmental Distraction (AMD)- A Clinical overview

The main clinical and radiological defect in cleft maxilla is localised at the region of nasomaxillary complex and thereby the increased focus on maxillary interventional correction. During the period of development, the affected individual undergoes a series of periodic treatment approaches aimed towards normalisation of the function and aesthetics. However, such interventional procedures can have otherwise effects on the restriction of growth. Surgical and facial orthopaedic interventions can cause protrusion of the premaxilla. This influences the depth and height of the upper jaw and thus the total height causing clockwise rotation of the face. Similarly, the depth of the posterior maxilla is found to be reduced in CLP cases. The advancement of the anterior maxilla with callus distraction for correction of the cleft maxilla was first reported by KraKasis and Hadjipetrou in 2004. The technique has been used since then with variable success and less predictability. The present table clinic is targeted to showcase the key features of various stages critical in planning the anterior maxillary distraction in adult maxillary hypoplasia cases. The requirement of precision in planning and treatment is high in such cases to minimize the adverse effects. The novel methodology discussed here is the combination of CBCT, face bow transfer and stereolithography for surgical planning and simulation. With the use of CBCT diagnostic capacity is enhanced, enabling visualisation of the defect. It also helps to simulate surgical procedure virtually and/or with the application of stereolithography. Use of the face bow facilitates biomechanical planning. The registration of the maxillomandibular relation to the cranial base serves as a guide to position the distractor. This is a critical step, as it dictates the direction of the distraction force vectors. Precise orientation and planning enable predictable movement of the anterior maxilla and control the extent of anterior open bite opening, in most cases. This contrasts with the overbite created with counter clockwise jaw rotation, reducing the post distraction orthodontic management. This table clinic presentation also draws home the key points in identifying and mitigating the potential complications during and after the distraction. The use of the present methodology enables a predictive treatment outcome for the cases with minimal complications associated with distraction with a marked reduction in the magnitude of callus molding. Therefore, with the application of this novel clinical paradigm for AMD, a predictable result can be achieved, which helps in the reduction of the treatment time and gives a stable outcome