Vanishing Psammoma Bodies in the Anterior Pituitary of the Human Newborn: An Immunohistochemical and Histometric Study

Adenohypophyses of human newborns contain characteristic psammoma bodies. Their numbers are maximal within 2 weeks of the neonatal period and diminish thereafter. They are very rare in infant pituitaries, seeming to disappear by shrinkage in that there is a significant direct correlation between their number and size. The bodies were found to contain a high concentration of endogenous peroxidase, thus suggesting that the enzyme may be responsible for their disappearance. A statistical majority of psammoma bodies were located within follicular lumens. By immunohistochemistry, the follicular epithelium surrounding psammoma bodies showed immunoreactivity for various pituitary hormones. Light microscopy demonstrated that adenohypophysial cells surrounding psammoma bodies contain randomly, scattered granules or globules exhibiting peroxidase activity. Extrusion of such granules into follicular lumens may play a role in the genesis of the concretions. The conspicuous lamellar nature of the calcified psammoma bodies suggests that waves of calcium deposition occur during their morphogenesis. Despite histologic similarities, the histochemical characteristics of this type of psammoma body differ from those in other organs as well as from the calcification encountered in prolactin (PRL)-producing pituitary adenomas.     

SYMPOSIUM: Experimental Biology 1995 Role of Mesangial Cell Ion Transport in Glomerular Physiology and Disease: ANGIOTENSIN II-INDUCED TYROSINE PHOSPHORYLATION IN MESANGIAL AND VASCULAR SMOOTH MUSCLE CELLS

• 1 Angiotensin II (AngII)-induced, activation of phospholipase C (PLC) and Ca²⁺-dependent Cl^? channels is an important signal transduction pathway for the regulation of vascular smooth muscle cell (VSMC) and glomerular mesangial cell contraction and growth. While AT receptors are traditionally thought to be G-protein coupled to the β isoform of PLC, recent evidence suggests that in some tissues AT receptors may also activate the PLC-γ isoform via tyrosine phosphorylation.
• 2 By western analysis, we identified PLC-γ1 in the above cell types. We found that within 3 min of exposure to 10^?7 mol/L AngII, tyrosine phosphorylation of PLC-γ1 was observed; however, peak response (> 3-fold increase) occurred within 0.5 min. In addition, pre-incubation of these cells with the tyrosine kinase inhibitor genistein blocked the tyrosine phosphorylation of PLC-γ1 by AngII. In contrast, preincubation with the tyrosine phosphatase inhibitor sodium vanadate increased the levels of tyrosine phosphorylation of PLC-γ1. Similar results were found when intracellular levels of 1,4,5-IP₃ were measured after AngII exposure.
• 3 By using patch clamp techniques on cultured rat mesangial cells exposed to AngII, we found that the release of 1,4,5-IP₃-sensitive intracellular Ca²⁺ stores stimulated low conductance Cl^? channels. Preincubation with genistein, abolished the usual 10-fold increase in Cl^? channel activity observed with AngII.
• 4 Therefore, we conclude that in VSMC and glomerular mesangial cells (i) AngII transiently stimulates PLC activity via tyrosine phosphorylation of the γ1 isoenzyme, (ii) tyrosine phosphorylation of PLC-γ1 and production of 1,4,5-IP₃ in response to AngII is dramatically inhibited by tyrosine kinase inhibition and stimulated by tyrosine phosphatase inhibition, (iii) activation of Ca²⁺-dependent Cl^? channels by AngII-induced release of 1,4,5-IP₃-dependent intracellular Ca²⁺ stores is also abolished by tyrosine kinase inhibition. In summary, this AngII-induced signal transduction cascade provides a possible mechanism for both the contractile and growth-stimulating effects of AngII on VSMC and glomerular mesangial cells.

     

Hypertension in the elderly: Age- and disease-related complications and therapeutic implications

Summary Effective treatment of hypertension in the elderly requires an understanding of both the progressive course of the disease and the impact of aging on the cardiovascular system, including physiological, genetic, lifestyle, and environmental factors. Review of the literature that has attempted to define the impact of an aging process on cardiovascular structure and function reveals a diversity of findings and interpretations. However, in general, normotensive elderly subjects exhibit the heart and vascular characteristics of muted hypertension, including many features of younger hypertensive patients: cardiac hypertrophy, diminution in resting left ventricular early diastolic filling rate, increased arterial stiffness and aortic impedance, diminution in the baroreceptor reflex, a diminished response to catecholamines and diminished renal blood flow, and an increase in peripheral vascular resistance (PVR). Treatment of elderly hypertensives is more challenging because of the greater likelihood of the presence of concomitant diseases, most importantly, coronary and peripheral atherosclerosis, renal dysfunction, and diabetes mellitus. Isolated systolic hypertension (ISH), the most common form of hypertension in the elderly, has also been clearly shown to be an important predictor of cardiovascular morbidity and mortality, including coronary artery disease, congestive heart failure, and stroke. Treatment of ISH has been shown to lower systolic pressure safely and effectively in the elderly. By reducing PVR, and possibly the arterial stiffness, and thus the early reflected pulse waves, vasodilators, including calcium antagonists, may lower these three components of arterial impedance, and hence lower the arterial load on the heart. The cardiac hypertrophy and reduced left ventricular filling rate associated with hypertension in older individuals can also be ameliorated, to some extent, by calcium channel blockers.Proceedings of a symposium held in Atlanta, Georgia on March 2, 1991.     

Cerebral venous angiomas: Surgery as a mode of treatment for selected cases

Summary Eleven patients with venous angiomas, 6 males and 5 females ranging in age from 4 to 58, are presented. Four patients presented with intracerebral haematoma and 3 patients had associated cavernous angioma, respectively. Patients with intracerebral haematoma had signs and symptoms due to the localication of the haematoma. The other patients presented with headache, seizures, vertigo, ataxia and mental disturbances. Pre-operative diagnosis was based on computerized tomography, magnetic resonance imaging and cerebral angiography. In 9 surgical cases it was confirmed by histopathological examination of operative specimens.After establishing the type, size and location of the lesion decision for operative treatment was made in nine cases, in four of them because of the presence of an intracerebral haematoma and in 5 of them due to severe disability. Eight of these 9 patients recovered completely and one improved. No severe cerebral oedema was encountered after converging medullary veins were excised and main draining veins partially coagulated.In this small series we encountered an unexpectedly large percentage of venous angiomas causing intracerebral haemorrhage which are commonly considered more benign than other vascular malformations. After reviewing previously reported cases of venous angiomas causing intracerebral haemorrhage and severe neurological deficit we think that the term benign is worth reconsidering. We propose a thorough examination of each case of venous angioma and the operative treatment when appropriate taking into account patients state and location of angioma.     

Calcinosis in juvenile dermatomyositis

A retrospective study of the radiographs and clinical records of 39 children with dermatomyositis, followed up at a referral centre for a mean period of eight years, revealed calcinosis in 29 children (18 giris, 11 boys). Clinical presentation of calcinosis was unpredictable and variable, ranging from four months to 12 years after onset of disease. Subcutaneous calcilication, often associated with subsequent ulceration of overlying skin, was observed more frequently than calcinosis in intermuscular fascial planes (29:7). Subcutaneous calcinosis was demonstrated most commonly about the knees and elbows and in the fingers and toes. Intermuscular calcinosis affected the fascial planes around the quadriceps, deltoid, biceps, and the gastrocnemius/soleus muscles.Calcinosis, predominantly of the subcutaneous lesions, regressed spontaneously in eight of 11 children where this could be assessed over a one to four year period. This high rate of spontaneous resolution must complicate evaluation of the efficacy of proposed anti-calcinotic treatments in juvenile dermatomyositis.While no apparent relationship was established between subcutaneous calcinosis, which was present in all 29 of the affected patients, and disease activity or severity, all seven children with the additional, extensive, and classical intermuscular fascial plane calcification developed this complication early and had severe disease.These findings are discussed in relation to previous studies.     

Metallurgical evaluation of the compatibility of surgical clips with their appliers

Summary Five aneurysm clips and their respective appliers (Heifetz, Vari-Angle, McFadden, Scoville, and Yaargil) were tested for the production of small metal shards that could provoke a foreign body reaction or increase the risk of a stresscorrosion failure. Pivot and Vari-Angle-McFadden clips produced numerous large shards, the Scoville clip produced a few fine shards, and the Yaargil and Heifetz clips produced none. Metal shard production due to cold metal transfer is attributed to the abrasive mechanical interaction between clips and appliers made from metals with different degrees of hardness.     

Giant aneurysm of the calloso-marginal artery

A giant aneurysm of the right callosomarginal artery is reported in a 3-month-old child. This location is rare: including our case reported here, only three cases have been described. Clinicoradiological findings are presented and the surgical procedure is illustrated.     

可溶性血管细胞黏附分子1在妊高征发病中的作用

目的　研究可溶性血管细胞黏附分子 1(solublevascularcelladhesionmolecule - 1,sVCAM - 1)在妊高征发病中的作用。方法　用酶联免疫吸附法 (ELISA)测定 6 7例孕妇血清中sVCAM - 1水平 ,其中正常妊娠组 15例 ,妊高征组 5 2例。结果　中、重度妊高征患者血中sV CAM - 1水平显著高于正常妊娠组 (P <0 .0 1) ;轻度妊高征患者与正常妊娠组相比 ,虽无统计学差异 ,但有升高趋势 ;妊高征组产后该指标下降 ,与正常妊娠组比较无显著性差异 (P >0 0 5 )。sVCAM - 1浓度与平均动脉压呈正相关 (r =0 .5 4 2 ,P <0 .0 1)。结论　妊高征患者血中sVCAM - 1水平升高 ,表明内皮细胞损伤在妊高征的发病中起重要作用。     

颜面皮肤癌VEGF和NOS表达及相关性

[目的]研究血管内皮生长因子(VEGF)、诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)在颜而皮肤癌的表达及其相关性.[方法]应用免疫组化方法检测47例颜面皮肤癌标本VEGF、iNOS和eNOS的表达,并对其相关性进行统计分析.[结果]47例颜面皮肤癌组织中,表达iNOS、eNOS、VEGF的分别为63.83%、74.47%、68.09%;VEGF与iNOS的表达具有明显相关性(P＜0.01),VEGF与eNOS的表达无明显相关性(P＞0.05);VEGF的表达与颜面皮肤癌肿瘤分化程度呈正相关,与临床分期及病理分型无关.iNOS表达与颜面皮肤癌的分化程度及临床分期呈正相关,与病理分型无关.eNOS表达与颜面皮肤癌病理分型、临床分期和分化程度均无关.[结论]VEGF与iNOS的表达具有明显相关性,iNOS和VEGF在肿瘤生成过程中起重要作用.     

Acute effects on systemic circulation after intratracheal instillation of Curosurf or Survanta in surfactant-depleted newborn piglets

Systemic vasodilatation in surfactant-depleted newborn piglets is induced by 200 mg/kg of modified porcine lung surfactant (Curosurf™). The aim of this investigation was to study whether this effect is dependent on dose and could further be induced by instillation of a bovine surfactant preparation (Survanta™). Twenty-two 3–5-d old piglets were subjected to repeated saline lung lavage and then randomized to one of three groups. Instillation of either Curosurf 100 mg/kg ( n = 8), Survanta 100 mg/kg ( n = 7) or Curosurf 200 mg/kg ( n = 7) was performed through the endotracheal tube. Systemic vascular resistance decreased 7 (± 4)%, 15 (± 12)% and 18 (± 6)% in the three groups, respectively ( p < 0:05 in all three groups). A significant difference between the high and low dose Curosurf groups was found ( p < 0:05), whereas no significant difference was seen between the Curosurf 100 mg group and the Survanta group. The decrease in vascular resistance was compensated by an increase in cardiac output, resulting in a stable mean arterial blood pressure. In conclusion, both Curosurf and Survanta induce a significant decrease in systemic vascular resistance in surfactant-depleted newborn piglets. A more pronounced effect was observed after 200 mg/kg than after 100 mg/kg of Curosurf.