Systemic bevacizumab as adjuvant therapy for recurrent respiratory papillomatosis in children: A series of three pediatric cases and literature review.

Recurrent respiratory papillomatosis (RRP), a viral disease caused by human papillomavirus (HPV), is the most common benign neoplasm of the larynx among children and the second most frequent cause of infantile hoarseness. The course of the disease is variable; some patients experience spontaneous remission, while others may develop an aggressive respiratory compromise. Especially juvenile-onset RRP cases experience shorter intervals between surgical interventions and thus more surgeries overall, causing high rates of depression and voice-related quality of life. Various local adjuvant therapies have been studied with mixed efficacy and some early potential but have failed to show consistent effect across large cohorts of patients. Bevacizumab, a recombinant monoclonal antibody that inhibits VEGF, has shown efficacy in patients with rapid regrowth of papillomas with severe airway compromise, and/or distal multisite spread of disease. We present three juvenile-onset RRP cases successfully managed with systemically administered bevacizumab.

Modelo Matemático de VIH bajo la Administración de un Antirretroviral / HIV Mathematical Model considering Antiretroviral Administration

RESUMEN En este trabajo se propone un modelo matemático consistente de cuatro ecuaciones diferenciales ordinarias que describen la evolución del VIH en un individuo seropositivo y el efecto de un antirretroviral en el proceso de replicación del virus en las células T CD4+. Con el propósito de determinar la efectividad del medicamento en el largo plazo se analizan los casos con y sin el tratamiento antirretroviral para observar el efecto en la población de células T CD4+ sanas e infectadas. Con el modelo matemático propuesto se encuentra un caso en el cual el tratamiento antirretroviral permite mantener una concentración de T CD4+ no infectadas clínicamente saludable en el organismo. Mediante la aplicación del método de Conjuntos Compactos Invariantes se establecen los límites máximos para las poblaciones de células sanas e infectadas, así como la concentración del VIH libre en el organismo. Finalmente, se realizan simulaciones numéricas para ilustrar los resultados en el plano temporal, se grafican las soluciones del sistema y los límites superiores obtenidos, estos permiten observar el valor máximo que pueden llegar a alcanzar las poblaciones de células sanas, las infectadas y la concentración de VIH en el torrente sanguíneo.

ABSTRACT In this work, we present a proposal of a mathematical model of four ordinary differential equations that describe the evolution of HIV in an HIV-positive individual and the effect of an antiretroviral in the process of virus replication in CD4+ T cells. In order to determine the long-term effectiveness of the drug, the cases with and without antiretroviral treatment are analyzed to observe the effect on the population of healthy and infected CD4+ T cells. With our mathematical model, we are able to obtain a case where the antiretroviral allows a clinically healthy concentration of uninfected CD4+ T cells. Additionally, by applying the Compact Invariant Sets method we determine maximum values for the concentration of free HIV and both cells populations, healthy and infected. Finally, we perform numerical simulations in order to illustrate our results in the temporal plane, we plot the solutions of the system and their corresponding upper bounds, the latter allow us to define the maximum values of the HIV concentration in the bloodstream and the infected and healthy cells populations.

Positron emission mammography is a useful adjunct in assessment of dense breasts.

Worldwide breast cancer remains as the most common malignancy in women and the numbers who form a subgroup with dense breast parenchyma are substantial. In addition to mammography, the adjuncts used for further evaluation of dense breasts have been anatomically based modalities such as ultrasound and magnetic resonance imaging. The practice of functionally based imaging of breasts is relatively new but has undergone rapid progress over the past few years with promising results. The value of positron emission mammography is demonstrated in patients with dense breasts and mammographically occult disease.