Invasive pulmonary aspergillosis: frequency and meaning of the “hypodense sign” on unenhanced CT

The purpose of this study was to establish the diagnostic value of central hypointensity ("hypodense sign") in lung consolidations or nodules, in severely immunocompromised or neutropenic patients, suspected of having invasive pulmonary aspergillosis (IPA), and to assess its recognition on unenhanced CT scans. Serial CT scans of the lung were retrospectively reviewed in 43 consecutive immunosuppressed patients with IPA, and assessed for the presence of the hypodense sign using standard mediastinal and lung windowing settings, as well as a special, narrower window setting (width 110-140 HU; level 15-40 HU). The temporal relationship between the occurrence of the first CT-finding suspicious of IPA and the appearance of the hypodense sign, as well as between this and the occurrence of the crescent sign, cavitation or reduction in lesion size, was evaluated. Additionally, CT-scans from 89 immunocompromised patients with viral (n=45) or bacterial (n=44) pneumonia, investigated in the same time period at our institution were reviewed, with respect to the presence of the "hypodense" sign. Unenhanced CT scans revealed the hypodense sign in 11 neutropenic patients and 2 severely immunocompromised patients, out of a total of 43 patients with IPA evaluated in this study (30.2%). The mean time between the appearance of the first CT-findings of IPA (large nodule or consolidation +/- positive halo sign) and the hypodense sign was 7.8 days, while the time interval between the hypodense sign and the occurrence of crescent sign, cavitation, or decrease of the lesion's size was 8.3 days. The hypodense sign did not occur in any of the patients with viral or bacterial pneumonia, in the control series. We consider the hypodense sign to be a supplementary tool in the diagnosis of IPA. Its sensitivity was low in our series, but the high specificity makes it valuable in predicting IPA, anticipating the occurrence of cavitation or crescent sign, which are considered specific, but late findings of IPA. The hypodense sign is recognizable also on unenhanced CT, when a narrower lung window setting is used.

Steroid Profile in an Adrenocortical Carcinoma Producing Aldosterone

We report a rare case of primary aldosteronism due to an adrenocortical carcinoma. A 61-year-old woman with a history of hypertension and hypokalemia was referred for evaluation of a 4.2 cm measuring adrenal mass without secondary signs of malignancy. Endocrinological testing was consistent with primary aldosteronism. The patient underwent surgical resection of the adrenal mass; histology revealed an adrenocortical carcinoma. Postoperatively blood pressure, serum potassium, and aldosterone returned to normal. Four months after adrenalectomy, the patient presented again with hypokalemic hypertension and was found to have metastatic disease. Endocrinological investigation revealed primary aldosteronism and subclinical autonomous glucocorticoid hypersecretion. Careful hormonal investigation should be obtained in patients with adrenal masses causing excessive aldosterone secretion. In uncertain cases of primary aldosteronism, we would suggest to measure 18-hydroxycortisol levels, as excessive amounts may indicate adrenocortical carcinoma.

Adrenocortical carcinoma producing 11-deoxycorticosterone: a rare cause of mineralocorticoid hypertension

A 37-yr-old man presented with the classic signs of mineralocorticoid excess hypertension and hypokalemia. The cause was not aldosterone excess, but elevation of plasma 11-deoxycorticosterone (DOC). Computed tomography (CT) scans showed a large right adrenal mass without signs of metastatic disease. The tumor was removed by open laparotomy, and histology revealed an adrenocortical carcinoma. Two yr after diagnosis, the patient is in good general condition and there is no sign of recurrence or metastatic disease, despite the large tumor size. DOC producing adrenocortical carcinomas causing mineralocorticoid hypertension are very rare, so far only 10 cases have been described in the literature.

Extensive peritoneal and omental lymphomatosis with raised CA 125 mimicking carcinomatosis: CT and intraoperative findings

Diffuse peritoneal and omental seeding are well-known forms of dissemination of metastatic carcinoma. A wide variety of primary neoplasms may cause peritoneal and omental carcinomatosis, most commonly carcinomas of the ovary, gastrointestinal tract and breast. Extensive involvement of the peritoneal cavity with lymphoma is, however, rare. The association of peritoneal lymphoma with a raised CA 125, a tumour marker which is commonly raised in ovarian carcinoma, is a highly challenging clinical situation, which to our knowledge has not been published before in the medical literature. Not being aware of the possibility of this unusual combination of clinical, laboratory and imaging findings can lead to an erroneous diagnosis, as in our case.

Comparison of pulsatile and nonpulsatile perfusion of the lung in an extracorporeal large animal model

OBJECTIVE

Extracorporeal lung-perfusion models are widely used to evaluate pulmonary preservation techniques and reperfusion injury. However, these models mainly depend on nonpulsatile flow, which is not physiological and can subsequently lead to pulmonary edema. Observation in a standardized setting and reliability of functional and structural data assessment are therefore limited. To overcome these limitations we developed a new extracorporeal large animal lung perfusion model utilizing pulsatile flow to perfuse the pulmonary vasculature.

METHODS

Lungs of juvenile domestic pigs were in situ preserved with 2 liters Perfadex and stored for 3 h at 10 degrees C. Thereafter, reperfusion of the lung was performed in an extracorporeal blood perfusion circuit employing either a modified roller pump with pulsatile module (300 ml/min; pulsation rate 90/min) or a standardized roller pump with continuous flow (30 ml/min). Ventilation was performed with physiologic room air (350 ml; 16/min) for 1 h. Pulsatile and nonpulsatile perfusion was performed in 2 groups (group NP: nonpulsatile; group P: pulsatile flow, n = 7) during reperfusion. Peak inspiratory pressure (PIP), mean pulmonary artery pressure (PAP), and oxygenation capacity (DeltaPO(2)) were continuously measured. For control of the effectiveness of the pulsatile perfusion pressure waveforms were obtained directly from the native pulmonary artery of both groups. Malondialdehyde (MDA) as a parameter for lipid peroxidation and endothelial cell damage was assessed at 10, 30 and 50 min reperfusion. At the end of the study, pulmonary water content was assessed by means of wet-to-dry ratio (W/D ratio). The tissue was further processed for microscopic analysis.

RESULTS

PIP increased significantly in both groups during reperfusion. Mean PAP in both groups increased to 60 mm Hg after 20 min followed by a decrease after 60 min to 40 mm Hg. Pressure waveforms of the pulmonary artery showed sufficient pulsatility in the pulmonary vasculature with a systolic/diastolic pressure difference of 15 mm Hg whereas the pressure difference was 3-5 mm Hg in the nonpulsatile group. DeltaPO(2) was stable in groups NP and P during reperfusion (30 min: NP: 66.4 (62.2-88) mm Hg; P: 74.8 (65-81.7) mm Hg) without any statistically significant differences between the groups. MDA in group NP decreased over the reperfusion period from 6.2 (3.3-6.3) microM at 10 min to 5.2 (3.2-6.1) microM at 50 min, whereas in group P the level increased and was significantly higher after 50 min reperfusion compared to group NP [6.6 (6.1-9.2) microM at 50 min; p = 0.016]. W/D ratio was 6.7 (6.3-7.0) in group NP and 6.8 (6.3-7.6) in group P. Light microscopy evaluation showed no differences between both groups regarding severity of intra-alveolar and interstitial edema and numbers of intra-alveolar, intracapillary and interstitial granulocytes.

CONCLUSION

Although effective pulsatile perfusion of the pulmonary vasculature was achieved by means of a modified roller pump, this measure obviously did not improve functional parameters nor did it significantly reduce the edema formation after 3 h ischemia in this extracorporeal lung perfusion model. The use of pulsatile perfusion is therefore not mandatory in the extracorporeal setting of a large animal lung perfusion model.

Value of positron emission tomography for lung cancer staging

OBJECTIVE

The therapeutic strategy in non-small-cell lung cancer (NSCLC) requires exact staging of tumour invasion (T) as well as differentiation between ipsi- and contralateral lymph node invasion (N1/2 vs N3). [18F]FDG-positron emission tomography (FDG-PET) has been shown to detect invaded N with high accuracy while correct determination of T appears to be unclear. The purpose of this prospective study was to evaluate benefit and necessity of 18FDG-PET as an additive to conventional staging modalities.

METHODS

Forty patients with suspected non-small-cell lung cancer (NSCLC) were staged by means of computed tomography (CT), bronchoscopy, mediastinoscopy and bone scintigraphy. Additionally, attenuation corrected FDG-PET of the thorax was performed pre-operatively for analysis of T and N topography. After surgical resection with radical lymphadenectomy T and N staging results of CT and PET were compared with the pathological diagnoses. Specificity, sensitivity, positive predictive value and accuracy of CT and PET were calculated.

RESULTS

Twenty three squamous cell carcinomas, 14 adenocarcinomas, and three non-malignant tumours were found. Accuracy of CT-T was 0.75 and of PET-T 0.78; accuracy of CT-N was 0.78 and of PET-N 0.80. By combination of CT-T and PET-T accuracy was 0.88. Combination of CT-N and PET-N yielded an accuracy of 0.90. In two out of three cases, PET correctly determined T0. In two cases non-malignant inflammatory lymph nodes were falsely staged as malignant by PET.

CONCLUSIONS

Adequate pre-operative T- and N-staging is possible with both CT and FDG-PET. Accuracy can be improved by combination of CT and FDG-PET. FDG-PET is superior to CT in order to differentiate between malignant and benign tumours. However, acute inflammation can mimic malignant lymph node invasion. FDG-PET is justified as a supporting staging measure in cases presenting unclear differentiation between N2 and N3 after conventional staging and is helpful in cases with unclear cell type of the primary tumour.

Neonatal rat cartilage has the capacity for tissue regeneration

One of the most relevant issues in future medicine is tissue regeneration. Transplantation medicine alone cannot solve the problem of incurable conditions of vital organs. One approach to this might be the replication of the spontaneous regeneration that is found in embryonic/neonatal tissue. In this study, a tissue model for basic investigation of regeneration mechanisms in vivo was established. We demonstrated by histology and immunohistochemical staining for types I and II collagen that neonatal rat cartilage unlike adult cartilage has the capacity for rapid scarfree regeneration after full-thickness incision. The underlying mechanism was identified in the preserved proliferative capacity of neonatal chondrocytes. This in vivo model should prove useful in further studies of the role of cellular (e.g., GA cell cycle regulators) and extracellular (e.g., cytokines) factors in tissue regeneration and wound healing.

[Invagination caused by angiolipoma of the small intestine--a rare cause of occult gastrointestinal hemorrhage]

We present the case of a 71-year-old woman who was hospitalized because of a severe hip contusion. She had no symptoms or clinical signs of abdominal disease. Routine blood testing showed anemia, presumably owing to occult bleeding. Ultrasonographic abdominal screening revealed ileo-ileal intussusception with a central hyperechoic tumor suggestive of a lipoma as lead point. This diagnosis was confirmed at surgery, where a small bowel resection was performed. Histologic examination disclosed a benign angiolipoma of the ileum with a superficial shallow ulceration which obviously was the source of the occult blood loss. Diagnostic and therapeutic procedures and a literature review are discussed.

Immunophenotyping of acute lymphoblastic leukaemia in routinely processed bone marrow biopsy specimens

AIMS

To assess the value of immunophenotyping of acute lymphoblastic leukaemia (ALL) in routinely processed bone marrow trephine biopsy specimens and to establish a minimum panel of antibodies to assess lymphoid lineage and enable differentiation from acute myeloid leukaemia.

METHODS

45 routinely processed bone marrow biopsy specimens (formalin fixed, paraffin embedded and mildly decalcified in EDTA) reported to contain leukaemic infiltrates on the basis of cytomorphological and enzyme-cytochemical analysis of bone marrow smears (22 c-ALL, 11 T-ALL, 2 B-ALL, 10 u-ALL (unclassified)) were immunostained by the ABC method with a broad panel of 26 antibodies against various haemopoietic antigens.

RESULTS

Staining with antibodies directed against myeloperoxidase and lysozyme showed that seven cases were either biphenotypic or mixed leukaemias (2), or of myelogenous origin (acute myeloid leukaemia (AML)-M1 (2); AML-M4 (2); AML-M5a (1)). Five of these seven cases had been diagnosed initially as u-ALL. Three further cases with no compact leukaemic infiltrates were excluded. ALL was confirmed in the remaining 35 cases. Because of revised diagnoses, the total numbers of ALL subtypes changed (23 c-ALL, 8 T-ALL, 2 B-ALL, 2 u-ALL). Immunostaining of more than 10% of blast cells in at least one case was found with 19 of the 26 antibodies. The most sensitive lineage specific antibodies for diagnosis were found to be anti-CD10 for c-ALL (22/23) and beta F1 for T-ALL (6/8). Expression of aberrant antigens was fairly common--for example, 7/23 cases of c-ALL stained with antibodies against T cell associated antigens.

CONCLUSIONS

Immunohistochemical investigation of routinely processed bone marrow biopsy specimens enables reliable detection of ALL subtypes c-ALL and T-ALL. A minimum panel of antibodies, against TdT, CD34, myeloperoxidase, lysozyme, CD10, CD79a, and CD20, and the antibody beta F1, is proposed for the immunophenotyping of acute leukaemia.

Aortic plaque size and endometrial response in cholesterol-fed rabbits treated with estrogen plus continuous or sequential progestin

ERT is associated with a reduced incidence of coronary risk and cardiac events in postmenopausal women, but increases the risk of endometrial hyperplasia and carcinoma. Combined estrogen and progestin therapy protects the endometrium; however, its effects on heart disease risk factors are not completely known. In our study, 56 ovariectomized New Zealand White rabbits in 7 groups received a 0.5% cholesterol diet for 12 weeks. Controls were not treated with hormones. All other animals received (per kilogram body weight per week) intramuscular injections of either 0.3 mg estrogen (estradiol valerate) alone, 8.3 mg progestin (hydroxyprogesterone caproate) alone, estrogen and progestin continuously in 3 different dosages (0.3 and 8.3 mg; 1 and 8.3 mg; or 1 and 2.8 mg; estrogen and progestin, respectively), or 1 mg estrogen with 25 mg progestin sequentially in 2-week cycles. Eight non-ovariectomized animals served as further controls for endometrial analysis. Morphometric analysis of plaque size in the aortic arch showed that estrogen monotherapy, and the 3 combined therapies with 1 mg estrogen, significantly reduced intimal thickening (P<0.05). The application of progestin alone had no effect on plaque size. The endometrium was enlarged by 3-fold after estrogen treatment, and was decreased by half after progestin treatment, compared with control uteri (P<0.05). In all groups with combined hormone regimens, endometrial size was not significantly different from control uteri. However, these uteri showed more inflammatory reactions, especially when higher doses of hormones were given. In this animal model, doses of progestin that are able to successfully reduce the proliferative effect of estrogen on endometrium do not diminish the desirable antiatherosclerotic properties of estrogen.

Improvement of non-small-cell lung cancer staging by means of positron emission tomography

BACKGROUND

Exact staging of ipsi- and contralateral mediastinal lymph-node metastases (N 1/2 vs. N3) is essential for the therapeutic strategy in non-small-cell lung cancer (NSCLC). CT and mediastinoscopy are the standards of reference for N staging. However, even with these combined measures the extent of invasion of mediastinal lymph nodes can remain vague. 18FDG Positron Emission Tomography (18FDG-PET) has recently been shown to detect invaded nodes with high accuracy. The purpose of this study was to evaluate 18FDG-PET as an aid in N staging.

METHODS

27 patients with suspected NSCLC were clinically staged by means of CT, bronchoscopy, mediastinoscopy, and bone scintigraphy. Additionally, 18FDG-PET was performed preoperatively for analysis of topography of invaded lymph nodes. CT and 18FDG-PET were evaluated in a blinded fashion. Surgical therapy was performed with radical lymphadenectomy. CT N staging as well as PET N staging results were compared with the pathological diagnoses (pTN). Specificity, sensitivity, and accuracy of CT and PET in N staging were calculated.

RESULTS

14 squamous-cell carcinomas, 10 adenocarcinomas, and 3 non-malignant tumors were found. In 8 patients no invasion was found (N0), in 13 patients an ipsilateral invasion (N1/2), and in 3 patients a contralateral invasion (N3). In the correct detection of N1/2 the sensitivity of CT and of PET was 0.77, the specificity of CT and of PET was 0.79. The accuracy of CT was 0.74 and of PET 0.78. By combining CT and PET accuracy was 0.85.

CONCLUSIONS

Adequate preoperative LN staging is possible with both CT and 18FDG-PET. The accuracy, however, can be improved by a combination of CT and 18FDG-PET.

Disparate actions of mifepristone (RU 486) on glands and stroma in the primate endometrium

Besides being an antiprogestin, mifepristone (RU 486) was recently shown to antagonize oestrogen-dependent growth in the endometrium. To explore the molecular mechanisms for this phenomenon, we investigated whether or not the morphological effects of mifepristone are mediated by the progesterone receptor (PR) and whether mifepristone has disparate effects on the glandular epithelium and stroma. Six groups of hypogonadal, oestrogen-primed cynomolgus monkeys were treated for 2 weeks with: vehicle only (group I); mifepristone (group II); mifepristone plus progesterone at 0.2 mg/kg (group III), 1.0 mg/kg (group IV) or 5.0 mg/kg (group V); and progesterone only (5.0 mg/kg) (group VI). Histomorphological evaluation showed strikingly compacted stroma in the mifepristone-exposed endometria (group II), which was partially reversible by additional progesterone treatment (groups III-V). Glandular proliferation (pseudostratification, glandular mitoses) in mifepristone-treated monkeys was not significantly different from that in vehicle (oestradiol)-treated monkeys, but was inhibited by progesterone-only treatment. Cells containing vacuoles were scarce in the mifepristone-exposed endometrium, but detected frequently in progesterone-exposed endometria, indicating the strong antisecretory effect of mifepristone on glands. We conclude that oestrogen-dependent oedema in the stroma is antagonized by mifepristone. The reversal of this effect by progesterone suggests a PR-mediated mechanism. In glands, mifepristone is antiprogestogenic, but not antioestrogenic. Thus, stromal cells may be the target of antiprogestin-induced inhibition of oedema and endometrial growth.

The long-term prognosis of benign nephrosclerosis accompanied by focal glomerulosclerosis and renal cortical interstitial fibrosis, designated so-called decompensated benign nephrosclerosis by Fahr, Bohle and Ratscheck

The long-term prognosis of decompensated benign nephrosclerosis (DBN) was investigated by a retrospective analysis of the fate of 170 patients with this disease, which yielded the following results: 1) DBN carries a particularly poor prognosis. The renal survival rate (RSR) was 35.9% at 5 years and 23.6% at 10 years. The prognosis is therefore worse than that of any other primary glomerulopathy, with the exception of rapidly progressive glomerulonephritis. 2) DBN mainly affects males (sex ratio 5:1) and differs in this respect, among others, from focal sclerosing glomerulonephritis, in which the male:female ratio is 1.2:1. 3) The prognosis for females is no better than for males. 4) The severity of proteinuria at the time of biopsy has no influence on the prognosis. 5) The prognosis is particularly poor in cases in which the serum creatinine concentration is already elevated to more than 2.0 mg% at the time of biopsy. We conclude from these findings that not only the blood pressure, but also the serum creatinine concentration, should be assessed at regular intervals in all hypertensive individuals, so that DBN can be treated at an early stage, when it is still amenable to treatment.

Intrathecal therapy of leptomeningeal CEM T-cell lymphoma in nude rats with anti-CD7 ricin toxin A chain immunotoxin

We have established a new xenogeneic animal model of leptomeningeal metastasis (LM) by intracisternal inoculation of human CEM T-cell lymphoma into nude rats, and used it to evaluate the anti-lymphoma efficacy of an anti-CD7 ricin A chain immunotoxin (DA7). In vitro incubation with 2 microg/ml DA7 for 72 h inhibited CEM cells by 90% in a trypan blue exclusion assay. To establish its anti-lymphoma activity, one and four days after cisternal inoculation of 10(6) CEM cells, eight animals each were treated cisternally with 10 microg DA7 in 50 microl PBS or sham-treated with 50 microl PBS. Histopathologically, all eight sham-treated and five of eight DA7 treated animals showed typical features of LM with multilayers of tumor cells along the whole subarachnoid space and the ventricular walls, as well as subependymal and diffuse parenchymal tumor cell infiltration. Three DA7 treated animals were free of tumor. Two of these animals were asymptomatic long-term survivors (> 90 days). The third tumor-free animal suddenly died on day 51. Histology revealed viral myocarditis. Median symptom-free survival was 51 days (range 29-90+ days) in DA7 treated and 34 days (range 29-87 days) in sham-treated animals (p = 0.12, log-rank test). Histologically, no signs of neurotoxicity or systemic toxicity was found. However, DA7 treated animals showed a tendency to a slower weight increase on days 6-28 after tumor cell inoculation. Our results indicate that this model is useful in studying leptomeningeal seeding and intracisternal treatment of lymphoma. The demonstrated anti-tumor effect of DA7 treatment deserves further evaluation especially regarding the application of DA7 in early stages of LM from T-cell lymphoma.

Human glomerular structure under normal conditions and in isolated glomerular disease

Investigation of the human glomerulus in health and disease shows that the human glomerulus comprises seven lobule-like structures with numerous anastomoses. The total length of the capillaries in a single glomerulus is 0.95 cm, making a total of 19 km for all 2-million glomeruli. The total surface area of all glomerular capillaries is 6,000 cm2. The total filtration surface area is 516.1 cm2. Severe isolated disease of the glomerulus, as seen in acute endocapillary glomerulonephritis, membranoproliferative glomerulonephritis types I and II, membranoproliferative glomerulonephritis plus chronic membranous glomerulonephritis, diabetic glomerulosclerosis, and glomerular amyloidosis, does not lead to elevation of serum creatinine concentration, even if the filtration area is reduced to about 20% (as in diabetes) of the normal value. It is concluded that isolated glomerular disease does not lead to elevation of the serum creatinine concentration. Glomerulopathies in which there is acute or chronic elevation of the serum creatinine concentration are accompanied by acute renal failure or involvement of the renal cortical interstitium, respectively.

Renal morphology in essential hypertension: analysis of 1177 unselected cases

Morphological and clinical analysis of 1177 renal biopsies from nonselected patients with essential hypertension revealed compensated benign nephrosclerosis in 775 cases. Decompensated benign nephrosclerosis was found in 251 cases, and secondary malignant nephrosclerosis was found in 151 cases. This article describes the morphological and clinical features of decompensated benign nephrosclerosis, which has received little recognition until now. The morphological and clinical features of secondary malignant nephrosclerosis, which is induced by hypertension, are also considered. There is also a discussion of the differentiation of the latter from primary malignant nephrosclerosis, in which stenosis of the preglomerular vessels develops in the presence of normal blood pressure and leads secondarily to renal hypertension.

Diagnostic value of immunostaining for tryptase in patients with mastocytosis

The term "mastocytosis" is used to describe a heterogeneous group of disorders characterized by abnormal growth and accumulation of mast cells (MCs). Cutaneous and systemic variants exist. Systemic mastocytosis may show an indolent or malignant clinical course. In malignant mastocytosis (MM), the diagnosis often is missed because the MCs are morphologically abnormal and lack metachromatic granules or the underlying histologic picture is complex. The cytoplasmic serine protease tryptase is produced by MCs and is thought to be expressed at all stages of MC maturation. To assess the diagnostic value of tryptase staining in mastocytosis, tissue sections from 93 patients with mastocytosis, including MM (n = 37), systemic indolent mastocytosis (n = 47), urticaria pigmentosa (n = 5), MC leukemia (n = 2), and solitary skin mastocytoma (n = 2) were stained with the antitryptase antibody G3. The results were compared with those of Giemsa and chloroacetate esterase (CAE) staining. Using antitryptase antibody G3, MC infiltrates were identified in all patients examined, including those with MM (37 of 37), and virtually all the neoplastic MCs (> 95%) appeared to react with G3. In MM, significantly fewer MCs were positive in Giemsa (54.5%; p < 0.05) and CAE (78.8%; p < 0.05). Moreover, G3 produced clear diagnostic staining in all cases of MM, but the proportion of cases with clear diagnostic results (> 10% of neoplastic cells positive) was considerably lower with Giemsa (48.6%; p < 0.05) and CAE (75.7%; p < 0.05) staining. By contrast, tryptase, Giemsa, and CAE produced diagnostic staining of MCs in virtually all cases of systemic indolent mastocytosis, urticaria pigmentosa, and solitary skin mastocytoma. In systemic mastocytosis, survival was significantly reduced in cases with Giemsa-/tryptase+ or CAE-/tryptase+ tumor cells compared to those cases with Giemsa+ or CAE+ MC infiltrates (p < 0.001).

Does anti-atherogenic estradiol valerate treatment cause adverse effects on liver and uterus in NZW rabbits?

The rabbit has been a widely accepted animal model for atherosclerosis research since Anitschkow first used this animal in 1913 in identifying dietary-induced hypercholesterolemia as a major risk factor for atherogenesis. Experiments with cholesterol-fed rabbits have demonstrated the beneficial effects of estrogen treatment on the development of atheroma for more than 50 y. Clinical trials have found a reduction in cardiovascular events of up to 50% in postmenopausal women receiving estrogen replacement therapy. However, metabolic conditions in rabbits, as well as physiological estrogen serum levels, differ in some aspects from those in humans. In rabbits, experimentally-induced hormone levels are about 5- to 10-fold higher than those found in untreated animals. Normal physiological estrogen levels in rabbits are not cardioprotective under dietary-induced hypercholesterolemia. We investigated whether replacement induced "hyperestrogenemia" causes adverse effects on organs other than the cardiovascular system. Twenty-nine female rabbits were divided into 4 different groups, 2 without and 2 with estrogen treatment (1 mg estradiol valerate/kg body weight/w over 12 w). Organ weights, transaminases and uterine histology were examined. In rabbits treated with estrogen, we did not see relevant adverse effects on heart, kidney and liver weights, or on liver enzymes. But there was a significant increase in spleen weights, as well as notable changes in the endometrium with moderate inflammation. These findings indicate that the dosage of estrogen commonly used for atherosclerosis research does not cause serious disorders in the major organs of cholesterol-fed rabbits.

Effects of boswellic acids extracted from a herbal medicine on the biosynthesis of leukotrienes and the course of experimental autoimmune encephalomyelitis

Mixed acetylboswellic acids, pentacyclic triterpenes extracted from the gum resin of Boswellia serrata Roxb., significantly inhibited the ionophore-stimulated release of the leukotrienes (LT) B4 and C4 from intact human polymorphonuclear neutrophil leukocytes (PMNLs), with IC50 values of 8.48 micrograms/ml and 8.43 micrograms/ml, respectively. Purified acetyl-11-keto-beta-boswellic acid was about three times more potent as inhibitor of the formation of both LTB4 (IC50 = 2.53 micrograms/ml) and LTC4 (IC50 = 2.26 micrograms/ml) from human PMNLs in the same assay. The comparative agent MK 886 (3-[1-(4-chlorobenzyl)-3-t-butyl-thio-5-isopropylindol-2-yl]- 2,2-dimethylpropanoic acid, L-663,536, CAS 118, 414-82-7) was about 10 to 100-fold more active than the boswellic acids in inhibiting the formation of 5-lipoxygenase products in human PMNLs, with IC50 values of 0.0068 microgram/ml (LTB4) and 0.49 microgram/ml (LTC4). After daily intraperitoneal dosage the extract of mixed acetylboswellic acids (20 mg/kg) significantly reduced the clinical symptoms in guinea pigs with experimental autoimmune encephalomyelitis (EAE) between days 11 and 21. However, the inflammatory infiltrates in the brain and the spinal cord were not significantly less extensive in the treated animals than in the respective control group. The multiple intraperitoneal application of boswellic acids did not inhibit the ionophore-challenged ex vivo release of leukotrienes B4 and C4 from PMNLs separated from the blood of guinea pigs with EAE. The boswellic acids have thus been characterized as selective, non-redox and potent inhibitors of the biosynthesis of leukotrienes in vitro.

Expression of cell adhesion molecules by endothelium in the human lower uterine segment during parturition at term

OBJECTIVE

Our purpose was to determine whether the expression of certain adhesion molecules by endothelium in the human lower uterine segment at term varies with the degree of cervical dilatation.

STUDY DESIGN

Biopsy specimens of the lower uterine segment of 34 women undergoing cesarean section at term at various stages of cervical dilatation were immunostained for endothelial leukocyte adhesion molecule-1, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and platelet-endothelial cell adhesion molecule.

RESULTS

The expression of endothelial leukocyte adhesion molecule-1 was significantly greater at more than 6 cm dilatation than at less than 2 cm (p = 0.00031) as was that of vascular cell adhesion molecule-1 (p = 0.033). Expression of intercellular adhesion molecule-1 and platelet-endothelial cell adhesion molecule did not vary with the degree of cervical dilatation.

CONCLUSION

Cervical dilatation is associated with up-regulation of certain endothelial cell adhesion molecules. The findings support the hypothesis that certain processes associated with cervical dilatation at term resemble those involved in the acute inflammatory reaction.

Preeclamptic nephropathy -- an endothelial lesion. A morphological study with a review of the literature

OBJECTIVE

We investigated wether an endothelial lesion, postulated in pathogenesis of preeclampsia (PE) in general, is also pathogenetically relevant in the characteristic renal lesions of PE, presenting as special glomerular alterations, designated as "preeclamptic nephropathy".

STUDY DESIGN

Renal biopsies of 90 women with PE were analyzed by light microscopy (LM), immunohistology (IH) and electron microscopy (EM). Corresponding with clinical data clinicomorphological correlations were performed.

RESULTS

In IH and EM the altered glomeruli demonstrate an endothelial lesion. Consecutive morphological reactions could be revealed by EM, allowing a subdivision in different stages of disease. The late stage indicates the reversibility of these renal lesions. Close correlations were found between clinical and morphological data. Focal glomerulosclerosis presents a hyperperfusion lesion, developing only facultatively in PE as a result of hyperfiltration.

CONCLUSION

In preeclamptic nephropathy the first morphological substrate of renal changes with the key to pathogenesis presents itself as an endothelial lesion. This results in a disturbance of glomerular basement membrane permeability and in an imbalance of different mediator systems, with dominance of vasoconstrictive reactions but also coagulative-, reparation-, and proliferation-processes, leading to the characteristic glomerular alterations of preeclamptic nephropathy.