Unilateral variation in the origin of the inferior alveolar and buccal arteries: a case report / Variación unilateral en el origen de las arterias alveolar inferior y bucal: reporte de un caso

The maxillary artery (MA) is one of the terminal branches of the external carotid artery (ECA) and is located in the infratemporal fossa (IF). Some of the branches in this region are the inferior alveolar artery (IAA) and the buccal artery (BA), both descending branches. Here, we report an unusual unilateral origin of the IAA and the BA from a common trunk directly from the ECA. We conducted a routine dissection of both IF in a 54-year-old hispanic male cadaver. Fixed with Universidad de los Andes® conservative solution and red latex for vascular filling. On each side, the MA is observed superficially located over the lateral pterygoid muscle. On the right side, the IAA and the BA originate from a common trunk from the ECA approximately 5 mm prior to the bifurcation into their terminal branches. On the left side, the IAA originates from the MA that is immediately next to its origin, making a common trunk with the pterygoid branches. Knowing the morphology of the MA and its branches at the IF is important for oral and maxillofacial surgery procedures; and any variation in the origin or course of these arteries may result in the patient's increased morbidity during some invasive procedure in the area.

La arteria maxilar (AM) es una rama terminal de la arteria carótida externa (ACE), y se ubica en la región infratemporal (RI). Algunas de sus ramas en esta región son la arteria alveolar inferior (AAI) y la arteria bucal (AB), ambas ramas descendentes. En este trabajo informamos de un inusual origen unilateral de la AAI y de la AB a partir de un tronco común desde la ACE. Se realizó una disección de rutina de ambas regiones infratemporales en un cadáver de 54 años, sexo masculino, caucásico. Fijado con solución conservadora Universidad de los Andes® y repleción vascular con látex rojo. A cada lado, se observa la AM en ubicación superficial sobre el músculo pterigoideo lateral. Al lado derecho, la AAI y la AB se originan de un tronco común desde la ACE aproximadamente 5 mm antes de la bifurcación en sus ramas terminales. Al lado izquierdo la AAI se origina de la AM inmediato a su origen, formando un tronco común con los ramos pterigoideos. El conocimiento de la morfología de la AM y de sus ramas en la RI es de importancia en procedimientos odontológicos, de cirugía oral y maxilofacial. Por lo que cualquier variación en el origen o trayecto de estas arterias puede predisponer a un paciente a una mayor morbilidad durante algún procedimiento invasivo en la zona.

[Estrogen therapy in menopause. Clinical study in evolution (KEEPS) to explain the risk-benefit dispute to administration]. / Terapia con estrógenos en la menopausia. Estudio clínico en evolución (KEEPS) para explicar la controversia del riesgo-beneficio de su administración.

The Kronos Early Estrogen Prevention Study (KEEPS) is a randomized clinical and controlled study, with the objective of clarifying the controversy that arisen previous studies about the risk-benefit factor with use of estrogens in postmenopausal women. Healthy women aged 42-58 years who are within 36 months of their last menstrual period have been recruited to receive either oral estrogens or patches of estradiol; in addition both groups are given oral micronized progesterone for 11 days of each month. Outcomes will be carotid intimae medial thickness and the accrual of coronary calcium; collaterally subrogate outcomes will be lipoproteins concentrations, coagulation markers, bone densitometry, mammography, skin characteristics and cognitive evaluation. The hypothesis consists in the presence of a window of therapeutic opportunity for the use of estrogens in low dose in healthy women with recent menopause.

Estudio integral no invasivo de la estructura y función arterial: discusión de aspectos teóricos y prácticos del abordaje implementado en CUiiDARTE (centro universitario de investigación, innovación y diagnóstico arterial): [revisión] / Non-invasive integral study of arterial structure and function: discussion of theoretical and practical features of the approach implemented at CUiiDARTE (centro universitario de investigación, innovación y diagnóstico arterial): [review]

Los sistemas de prevención cardiovascular basados en la determinación de factores de riesgo presentan limitaciones para cuantificar el riesgo de un sujeto. Los factores de riesgo son predictores de aterosclerosis en la población, pero fallan en identificar qué sujetos desarrollarán la enfermedad y/o tendrán eventos cardiovasculares; los que frecuentemente se presentan en sujetos de riesgo bajo o intermedio. En este contexto, guías/consensos sugieren realizar estudios no invasivos en sujetos asintomáticos para estratificar el riesgo individual, detectar y tratar la aterosclerosis en etapa subclínica. Para ello se han propuesto diferentes abordajes que permiten caracterizar la estructura y/o función arterial por métodos no invasivos, brindando información complementaria, que adiciona a la obtenida con la determinación de los factores de riesgo. En Uruguay, recientemente se creó un centro universitario interdisciplinario (CUiiDARTE, Centro Universitario de Investigación, Innovación y Diagnóstico Arterial), que tiene entre sus objetivos implementar técnicas no invasivas para la evaluación integral de la estructura y función arterial, posibilitando dar respuesta a la necesidad de estratificación individualizada del riesgo cardiovascular y detección de aterosclerosis subclínica. En este trabajo se presenta el abordaje de evaluación vascular empleado en CUiiDARTE y basados en nuestra experiencia, se discuten aspectos teóricos y prácticos de los test no invasivos utilizados y parámetros estudiados.

Traditional risk factors-guided cardiovascular prevention/treatment has clear limitations in individual subjects management. Often, individuals with similar risk factor profiles have differences in the atherosclerosis development and are at different cardiovascular risk. Therefore, while risk factors are good predictors of atherosclerosis in a population, they cannot identify who will develop the disease and/or will have a cardiovascular event. In this context, there have been published guidelines calling for non-invasive atherosclerosis screening and risk stratification in asymptomatic subjects. Several approaches have been proposed for the vascular evaluation, and although the screening tests used vary among laboratories, in general terms their are underused. In Uruguay, it was recently created an interdisciplinary university center (CUiiDARTE, Centro Universitario de Investigación, Innovación y Diagnóstico Arterial), which has as a main aim the implementation of non-invasive techniques to evaluate the arterial structural and functional properties, that could allow stratifying the individual cardiovascular risk and identifying sub-clinical atherosclerosis. In this work we present the integral vascular approach used in CUiiDARTE and based in our experience we discuss, theoretical and practical issues related with the tests performed and parameters calculated.

Effect of D-003 on intimal thickening and circulating endothelial cells in rabbit cuffed carotid artery.

D-003 is a mixture of very-high-molecular-weight aliphatic primary acids purified from sugar-cane (Saccharum officinarum L.) wax, in which octacosanoic acid is the most abundant component. Previous experimental studies have shown that D-003 not only shows cholesterol-lowering and anti-platelet effects, but also reduces thromboxane B2 and increases prostacyclin levels. It acts by inhibiting cholesterol biosynthesis. The positioning of a non-occlusive silicone collar around the rabbit carotid artery results in the formation of a neointima. Collars were placed around the left carotid for 15 days. The contralateral artery was sham-operated. We included three experimental groups: A control group received vehicle, and two others received D-003 at 5 and 25 mg/kg until sacrificed. Samples of arteries were examined by light microscopy. To evaluate intimal thickening the cross-sectional areas of intima and media were measured. Neointima was significantly reduced in D-003-treated animals compared with controls. Furthermore, the circulating endothelial cell has been studied in this experimental model with endothelium damage. The results demonstrate the protective effect of D-003 on vascular endothelium of the studied rabbits. It is concluded that the protective effect of D-003 against neointima formation and circulating endothelial cells in this experimental model could represent potential beneficial pleiotropic effects in the anti-atherogenic profile of this substance, beyond its cholesterol-lowering and anti-platelet effects independently demonstrated.

Hypotrophy of conduit artery walls of the offspring of nitric oxide-defective rats.

The objective of the present study was to investigate the structure of the arterial walls of the offspring stemming from nitric oxide (NO)-defective hypertensive parents. The parents were treated with NG-nitro-L-arginine methyl ester (40 mg kg-1 day-1) for 5 weeks. Blood pressure was measured noninvasively in six 30-day-old rats and nine age-matched controls. The cardiovascular system was perfused with glutaraldehyde at 120 mmHg. The thoracic aorta and carotid artery were processed for electron microscopy, and geometry was determined by light microscopy. Endothelial cells, smooth muscle cells (SMC) and extracellular matrix (ECM) were determined by the point counting method in electron micrographs of the carotid artery. The blood pressure of experimental offspring was 150.0 +/- 2.3 vs 104.6 +/- 2.1 mmHg (P < 0.01) for the controls and their heart/body weight ratio of 3.9 +/- 0.1 vs 4.4 +/- 0.2 (P < 0.05) for the controls indicated cardiac hypotrophy. The wall thickness (tunica intima and media) of the thoracic aorta and carotid artery of experimental offspring was decreased to 78.9% (P < 0.01) and 83.8% (P < 0.01), respectively, compared to controls, as confirmed by a respective cross-sectional area of 85.3% (P < 0.01) and 84.1% (P < 0.01). The wall thickness/inner diameter ratio was reduced to 75% (P < 0.01) in the thoracic artery and to 81.5% (P < 0.01) in the carotid artery. No change in endothelial cell volume density or ECM was observed in the tunica intima of the carotid artery, and SMC volume density was lower in the tunica media (37.6 +/- 0.9 vs 44.7 +/- 1.1% for controls, P < 0.01), indicating compromised SMC development. Interference with arginine metabolism, a decrease in NO, and other factors are possible mechanisms underlying the structural alterations of the cardiovascular system of offspring from NO-defective hypertensive rats.

A comparative study of policosanol vs lovastatin on intimal thickening in rabbit cuffed carotid artery.

Policosanol is a cholesterol-lowering drug isolated from sugar cane wax, which acts by inhibiting cholesterol biosynthesis. Previous studies have demonstrated that policosanol inhibited smooth muscle cell (SMC) proliferation in the cuffed carotid artery of the rabbit and in arterial wall damage induced by forceps in the central artery of the ear of rabbits. The present study was undertaken to compare the effects of policosanol and lovastatin on SMC proliferation in the cuffed carotid artery of rabbits. Collars were placed around the left carotid for 7 and 15 days. The contralateral artery was sham operated. We studied eight experimental groups: two controls groups receiving vehicle for 7 and 15 days, respectively, a satellite sham operated control group, four groups treated with policosanol at 5 and 25 mg kg(-1)for 7 and 15 days and a reference group receiving lovastatin at 20 mg kg(-1)for 15 days. Samples of arteries were examined by light and electron microscopy. To evaluate intimal thickening the cross-sectional areas of intima and media were measured. Neointima was significantly reduced in treated animals compared with controls, but the reduction in lovastatin animals was significantly lower than in policosanol-treated groups. The SMC proliferation was studied by the immunohistochemical detection of proliferating cell nuclear antigen and the reduction observed in policosanol-treated rabbits was significantly larger than in lovastatin-treated animals. It is concluded that the protective effect of policosanol against neointima formation in this experimental model was slightly better than that of lovastatin.