Responses of blood pressure and catecholamine metabolism to high salt loading in endothelin-1 knockout mice.

The molecular mechanism responsible for salt sensitivity is poorly understood. Mice heterozygous for the null mutation of the endothelin-1 (ET-1) gene, Edn1, may be a potential tool for studying this mechanism, because they have elevated blood pressure and disturbances in central sympathetic nerve regulation. In the present study, we used this mouse model to examine the degree to which ET-1 contributes to the responses of blood pressure and catecholamine metabolism to high salt loading. Male Edn1+/- heterozygous mice and Edn1+/+ wild-type littermates were given either a high salt (8%) or a normal salt (0.7%) diet for 4 wk. During the normal diet, renal ET-1 levels in Edn1+/- mice were approximately 50% lower than ET-1 levels in wild-type mice, whereas the high salt diet decreased renal ET-1 levels by about 50% in both Edn1+/- and wild-type mice. The high salt diet significantly increased urinary sodium excretion and fractional excretion of sodium (FENa) but did not affect circulating plasma volume, serum electrolytes, creatinine clearance, or systemic blood pressure. In addition, urinary norepinephrine and normetanephrine excretion were significantly increased, indicating that salt loading can increase sympathetic nerve activity in normal mice. These responses to salt loading did not differ between Edn1+/- mice and their wild-type littermates. We conclude that physiological changes in ET-1 production do not affect the responses of blood pressure and catecholamine metabolism to salt loading, although the renal ET-1 content is decreased by salt loading.     

Prognostic impact of mitotic index of proliferating cell populations in cervical cancer patients treated with carbon ion beam

BACKGROUND:

The authors previously reported that the mitotic index of a proliferating cell population (pMI) was a potent prognostic factor in cervical cancer patients treated with photon beam therapy. In this study, they investigated whether the pMI accurately predicted prognosis in cervical cancer patients treated with carbon ion beam.

METHODS:

Tissue sections were obtained from 27 consecutively treated patients with stage IIIB bulky (19 patients) and stage IVA (8 patients) squamous cell carcinomas of the cervix treated with carbon ion beam at the National Institute of Radiological Sciences, Japan, as a phase I/II study with dose escalation methodology (52.8‐72 grays equivalent radiation dose/24 fractions). The mitotic index (MI) and Ki‐67 labeling index (Ki‐67‐LI) were determined by hematoxylin and eosin staining and immunohistochemical staining, respectively. The pMI was calculated using the following formula: pMI = MI/Ki‐67‐LI.

RESULTS:

The pMI ranged from 0.6 to 8.9 (mean, 3.9 ± 2.6; median, 3.2). Twelve of the 27 specimens had a pMI >3.5. The local control rate in tumors with a pMI >3.5 was 17%, significantly lower than the 73% in the tumors with a pMI <3.5 (P = .005). Multivariate analysis indicated that the pMI had the strongest impact on local control (standard regression coefficient = 0.48, P = .002) among the variables, including clinical stage, irradiated dose, age, and tumor volume.

CONCLUSIONS:

These results suggest that a high pMI is an indication of a poorer prognosis, and is a powerful prognostic factor in patients with squamous cell carcinomas of the cervix treated with carbon ion beam therapy. Cancer 2009. © 2009 American Cancer Society.     

The proximal form of mural thrombus in aortoiliac occlusive disease using computed tomography.

BACKGROUND: It is important to know the nature of proximal thrombus in patients with aortoiliac occlusive disease (AIOD) when juxtarenal aortic clamping is scheduled. This study was aimed to evaluate the shape and nature of thrombi at several sites of the abdominal aorta in patients with AIOD using enhanced computed tomography (CT). Final judgment was made according to the operative findings. METHODS: Between the years 1999 and 2001, 22 patients, who underwent aortobifemoral bypass, were enrolled. The shape and nature of their thrombi were examined at 4 points (superior mesenteric, suprarenal, juxtarenal and infrarenal arteries at the level of the 2 cm before the renal artery) and 88 slices of CT were examined retrospectively. RESULTS: There was mural thrombus in 31 slices, which could be classified into 4 shapes (crescent-shaped: 10 cases; magatama: 2; wavy: 12; circular: 6). The wavy and circular shaped thrombi were found to be atheromatous. Nine cases (40.9%) on operative findings were atheroma (wavy: 4; circular shaped: 5). The crescent shape might correspond to fibrin thrombus. Atheromatous thrombus clamping near the renal artery was thought to cause microthromboembolism to surrounding organs. CONCLUSIONS: It is recommended that the more proximal aorta or splanchnic arteries should be temporarily clamped during proximal procedures in patients with wavy or circular shaped thrombi at the juxtarenal aorta to prevent kidney or bowel infarction.     

A case of intracranial arteriovenous fistula in an infant with neurofibromatosis type 1

INTRODUCTION: Reported cases of arteriovenous fistula (AVF) with neurofibromatosis type1 (NF1) are rare. CASE REPORT: In this paper we report the first case of intracranial AVF in an NF1 infant who developed heart failure. Endovascular treatment using coils successfully obliterated the AVF. The mechanism underlying the AVF in this case was believed to be a congenital mesenchymal abnormality of the intracranial vessels. DISCUSSION: The mechanism underlying the development of heart failure in this case is also discussed.