Cutis rhomboidalis protects skin from malignant epithelial tumors.

Cutis rhomboidalis nuchae is a skin alteration which comes from chronic sun exposure and it integrates the solar elastosis group, acquiring a coriaceous aspect, with a yellowish and grooved surface. There is the occurrence of elastic and collagen fibers degeneration found in the dermis caused by ultraviolet radiation [1]. Another group of skin diseases which has solar exposure as a determining factor is the group of actinic keratoses, the non-melanoma malignant epithelial tumors {basal cell carcinoma (CBC) and squamous cell carcinoma (CEC)} [2]. However, the occurrence of actinic keratoses, CBCs or CECs on the area of cutis rhomboidalis is infrequent in dermatology clinical practice. The authors do not know why people with neoplasias and pre neoplastic lesions in some areas with chronic photo damage amendments (face and upper limbs), do not present the same pre and neoplastic lesions in areas with similar appearance of chronic sun damage (nape). The authors seek to understand why the nape is protected for pre and neoplastic lesions. We suggest that cutis rhomboidalis protects skin from malignant epithelial tumors in nuchae.

Cardiac and pulmonary arterial remodeling after sinoaortic denervation in normotensive rats.

Blood pressure variability (BPV) and baroreflex dysfunction may contribute to end-organ damage process. We investigated the effects of baroreceptor deficit (10 weeks after sinoaortic denervation - SAD) on hemodynamic alterations, cardiac and pulmonary remodeling. Cardiac function and morphology of male Wistar intact rats (C) and SAD rats (SAD) (n=8/group) were assessed by echocardiography and collagen quantification. BP was directly recorded. Ventricular hypertrophy was quantified by the ratio of left ventricular weight (LVW) and right ventricular weight (RVW) to body weight (BW). BPV was quantified in the time and frequency domains. The atrial natriuretic peptide (ANP), alpha-skeletal actin (α-skelectal), collagen type I and type III genes mRNA expression were evaluated by RT-PCR. SAD did not change BP, but increased BPV (11±0.49 vs. 5±0.3 mmHg). As expected, baroreflex was reduced in SAD. Pulmonary artery acceleration time was reduced in SAD. In addition, SAD impaired diastolic function in both LV (6.8±0.26 vs. 5.02±0.21 mmHg) and RV (5.1±0.21 vs. 4.2±0.12 mmHg). SAD increased LVW/BW in 9% and RVW/BW in 20%, and augmented total collagen (3.8-fold in LV, 2.7-fold in RV, and 3.35-fold in pulmonary artery). Also, SAD increased type I (~6-fold) and III (~5-fold) collagen gene expression. Denervation increased ANP expression in LV (75%), in RV (74%) and increased α-skelectal expression in LV (300%) and in RV (546%). Baroreflex function impairment by SAD, despite not changing BP, induced important adjustments in cardiac structure and pulmonary hypertension. These changes may indicate that isolated baroreflex dysfunction can modulate target tissue damage.