Intranuclear localization of snRNP antigens.

Anti-Sm antibodies recognize a group of small, nuclear RNA-protein complexes (snRNPs) containing U1, U2, U4, U5, and U6 snRNAs. Anti-RNP antibodies only react with U1 snRNA-containing complexes. The intranuclear distribution of snRNP particles was studied by double immunofluorescence staining of human fibroblasts. Mouse monoclonal anti-Sm antibodies and polyclonal patient sera reacting with different peptides in the snRNP complexes were used. The immunofluorescence patterns obtained with fluorescein isothiocyanate-conjugated anti-mouse Ig and tetramethylrhodamine isothiocyanate-conjugated anti-human Ig second antibodies were examined using computer analysis of digitized images. With this approach the similarity of different patterns could be visualized and estimated with mathematical methods. It was found that human anti-Sm serum as well as three different anti-RNP sera produced speckled patterns overlapping with the anti-Sm monoclonal pattern. Thus, Sm antigenic intranuclear domains also reacted with anti-RNP antibodies, suggesting a high degree of co-localization of the antigenic structures. A partial overlap was found between speckles detected by mouse anti-Sm antibodies and a human La-antiserum. No significant co-localization occurred between speckles detected by mouse anti-Sm antibodies and speckles detected by human antisera reacting with Scl-70 and centromeric antigens. As the U1 snRNP complex is believed to play a role in the splicing of RNA polymerase II transcripts, it appears that the speckles detected by Sm and RNP antibodies may be regions of hnRNA synthesis and mRNA processing. Although no function has been demonstrated for the U2, U4, U5, and U6 snRNPs, the co-localization with the U1 RNA complexes shown in this report indicate that they too participate in some aspect of mRNA processing. The results suggest that computer-assisted analysis of nuclear immunofluorescence patterns will be a useful tool in studies of the spatial and functional organization of the interphase nucleus.

Minimizing contrast medium doses to diagnose pulmonary embolism with 80-kVp multidetector computed tomography in azotemic patients.

BACKGROUND: In diagnosing acute pulmonary embolism (PE) in azotemic patients, scintigraphy and magnetic resonance imaging are frequently inconclusive or not available in many hospitals. Computed tomography is readily available, but relatively high doses (30-50 g I) of potentially nephrotoxic iodine contrast media (CM) are used. PURPOSE: To report on the diagnostic quality and possible contrast-induced nephropathy (CIN) after substantially reduced CM doses to diagnose PE in azotemic patients using 80-peak kilovoltage (kVp) 16-row multidetector computed tomography (MDCT) combined with CM doses tailored to body weight, fixed injection duration adapted to scan time, automatic bolus tracking, and saline chaser. MATERIAL AND METHODS: Patients with estimated glomerular filtration rate (eGFR) <50 ml/min were scheduled to undergo 80-kVp MDCT using 200 mg I/kg, and those with eGFR >or=50 ml/min, 120-kVp MDCT with 320 mg I/kg. Both protocols used an 80-kg maximum dose weight and a fixed 15-s injection time. Pulmonary artery density and contrast-to-noise ratio were measured assuming 70 Hounsfield units (HU) for a fresh clot. CIN was defined as a plasma creatinine rise >44.2 micromol/l from baseline. RESULTS: 89/148 patients (63/68 females) underwent 80-/120-kVp protocols, respectively, with 95% of the examinations being subjectively excellent or adequate. Mean values in the 80-/120-kVp cohorts regarding age were 82/65 years, body weight 66/78 kg, effective mAs 277/117, CM dose 13/23 g I, pulmonary artery density 359/345 HU, image noise (1 standard deviation) 24/21 HU, contrast-to-noise ratio 13/13, and dose-length product 173/258 mGy x cm. Only 1/65 and 2/119 patients in the 80- and 120-kVp cohorts, respectively, with negative CT and no anticoagulation suffered non-fatal thromboembolism during 3-month follow-up. No patient developed CIN. CONCLUSION: 80-kVp 16-row MDCT with optimization of injection parameters may be performed with preserved diagnostic quality, using markedly reduced CM doses compared with common routine practice, which should be to the benefit of patients at risk of CIN.

The cell cycle inhibitor p57(Kip2) promotes cell death via the mitochondrial apoptotic pathway.

The p57(Kip2) gene belongs to the Cip/Kip family of cyclin-dependent kinase (CDK) inhibitors and has been suggested to be a tumor suppressor gene, being inactivated in various types of human cancers. However, little is known concerning p57(Kip2) possible interplay with the apoptotic cell death machinery and its possible implication for cancer. Here, we report that selective p57(Kip2) expression sensitizes cancer cells to apoptotic agents such as cisplatin, etoposide and staurosporine (STS) via a mechanism, which does not require p57(Kip2)-mediated inhibition of CDK. Translocation of p57(Kip2) to mitochondria occurs within 20 min after STS application. In fact, p57(Kip2) primarily promotes the intrinsic apoptotic pathways, favoring Bax activation and loss of mitochondrial transmembrane potential, consequent release of cytochrome-c into cytosol, caspase-9 and caspase-3 activation. In accordance, Bcl2 overexpression or voltage-dependent anion channel (VDAC) inhibition is able to inhibit p57(Kip2) cell death promoting effect. Thus, in addition to its established function in control of proliferation, these results reveal a mechanism whereby p57(Kip2) influences the mitochondrial apoptotic cell death pathway in cancer cells.

Contrast medium dose-to-GFR ratio: a measure of systemic exposure to predict contrast-induced nephropathy after percutaneous coronary intervention.

BACKGROUND: The contrast medium (CM) dose-to-eGFR (estimated glomerular filtration rate) ratio has recently been advocated to express systemic exposure to CM in assessing the risk of contrast medium-induced nephropathy (CIN). PURPOSE: To evaluate how CIN risk might vary with decreasing eGFR at fixed CM-dose/eGFR ratios and other CIN risk factors, and to find a relatively safe CM-dose/eGFR ratio. MATERIAL AND METHODS: 391 patients underwent primary coronary angioplasty for ST-segment elevation acute myocardial infarction. CM dose (grams iodine; g I), eGFR (ml/min), and preprocedural CIN risk factors were entered into a multiple logistic regression model. From the established statistical model, the probability of CIN (>or=44.2 micromol/l serum creatinine rise or oliguria/anuria) was calculated at various eGFR levels based on g-I/eGFR ratios of 1:2, 1:1, 2:1, and 3:1. RESULTS: At a g-I/eGFR ratio <1 the risk of CIN was 3%, while it was 25% at a g-I/eGFR ratio >or=1. Independent predictors of CIN were CM dose, eGFR, left ventricular ejection fraction (LVEF) and cardiogenic shock (ROC area =0.87). An estimated CIN risk of 10% would for example occur at a g-I/eGFR ratio of 1.5:1 in patients with 50% LVEF without shock. At a 1:2, 1:1, 2:1, and 3:1 g-I/eGFR ratio with 50% LVEF without shock, the CIN risk was about 2, 6, 18, and 30%, respectively, over a wide range of eGFR values (30-90 ml/min). At a 1:1 g-I/eGFR ratio with 50% LVEF+shock, 25% LVEF without shock, or 25% LVEF+shock, the CIN risk was 20, 55, and 80%, respectively. CONCLUSION: Relating CM dose to eGFR appears to be an attractive pharmacotoxic model to assess CIN risk. At fixed CM-dose/eGFR ratios, CIN risk increased marginally with decreasing eGFR. Limiting the CM dose in g I numerically to the eGFR value in ml/min or less may be relatively safe with regard to CIN, unless multiple risk factors are present.

The role of p73 in hematological malignancies.

The P73 gene is a homologue of the P53 tumor suppressor. Owing to its structural similarity with p53, p73 was originally considered to have tumor suppressor function. However, the discovery of N-terminal truncated isoforms with oncogenic properties showed a 'two in one' structure of its product, p73 protein. The full-length variants are strong inducers of apoptosis, whereas the truncated isoforms inhibit proapoptotic activity of p53 and the full-length p73. Thus, p73 is involved in the regulation of cell cycle, cell death and development. Moreover, it plays a role in carcinogenesis and controls tumor sensitivity to treatment. p73 is commonly expressed in tumor cells in hematological malignancies. Overexpression of p73 protein and aberrant expression of its particular isoforms, with very low frequency of P73 hypermethylation or mutations, were found in malignant myeloproliferations, including acute myeloblastic leukemia. In contrast, hypermethylation and subsequent inactivation of the P73 gene are the most common findings in malignant lymphoproliferative disorders, especially acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphomas. Assessment of P73 methylation may provide important prognostic information, as was confirmed in patients with ALL. This review summarizes some aspects of p73 biology with particular reference to its possible pathogenetic role and prognostic significance in hematological malignancies.

Histomorphological changes after renal X-ray arteriography using iodine and gadolinium contrast media in an ischemic porcine model.

BACKGROUND: Gadolinium contrast media (Gd-CM) are regarded as non-nephrotoxic or considerably less nephrotoxic than iodine contrast media (I-CM), and have therefore come to be used as a substitute for I-CM in patients with renal insufficiency in a variety of radiographic examinations. PURPOSE: To investigate renal histomorphological changes caused by Gd-CM in comparison with I-CM after renal X-ray arteriography in an ischemic porcine model,and to evaluate these changes in relation to the nephrotoxicity of the CM used. MATERIAL AND METHODS: Test solutions: gadopentetate, gadodiamide, iohexol, gadobutrol,iopromide, iodixanol, mannitol, and saline. The experiments were performed on 152 animals. Each pig was randomized to receive one test solution injected into the balloon occluded(10 min) right renal artery. The kidneys were evaluated histomorphologically.The severity of histomorphological changes was graded subjectively: 15 minimal, 25 mild, 35 moderate, and 4=marked. RESULTS: The main histological changes were 1) proximal tubular and glomerular necrosis,2) hemorrhage/congestion of the cortex, medulla, and glomeruli, 3) proximal tubular vacuolation, and 4) protein-filled tubules in the cortex and medulla. Necrosis and hemorrhage/congestion were more frequent after injections with gadopentetate, mannitol solution iso-osmotic to gadopentetate, and gadobutrol compared to all other groups(P<0.001). The degree of necrosis and hemorrhage/congestion was related to the degree of impairment of renal function, but inversely related to vacuolation and tubular protein filling. CONCLUSION: In ischemic porcine kidneys, the histomorphological changes caused by Gd-CM are similar to those caused by I-CM. Vacuolation appears to be independent of the osmolality and viscosity of the CM, and does not seem to be an indicator of renal impairment. "High-osmolal" Gd-CM are more nephrotoxic than "low- and iso-osmolal" I-CM when compared in equal volumes of concentrations, resulting in equal X-ray attenuation.

Demonstration of an amino terminal La epitope recognized by human anti-La sera.

In order to study the antigenic properties of the La protein we have isolated a 1650 base pair (bp)-long human cDNA encoding an anti-La reactive protein. Restriction enzyme analysis and DNA sequencing was used to compare this clone with two published but inconsistent partial sequences. Our clone extends about 220 bp further towards the 5' end than the two clones previously studied and includes a putative initiation codon. When introduced into an expression vector, stable fusion proteins were made both from the initial clone and from two deletion clones. The recombinant proteins were tested by immunoblotting against a panel of anti-La sera. All reacted with the fusion protein produced by the 1650-bp clone. About half of the anti-La sera showed reactivity against the recombinant protein from the shortest deletion clone. This indicates the presence of an epitope in the amino terminal part of the La protein, encoded by sequences not present in previously published clones.

Contrast media for CT. An analysis of the early pharmacokinetics.

Iohexol and meglumine-sodium diatrizoate were injected intravenously into 18 pigs as either a 99:1 or 1:99 mixture. Blood samples were taken for 30 minutes and the concentration of each of the two contrast media was measured by means of a double labeling technique with 125I and 131I. Relative concentrations of iohexol were significantly higher during the first 3 minutes when it was injected as a moderately hyperosmolar (99% iohexol) solution than when it was injected as a very hyperosomolar (99% diatrizoate) solution. The greater intravascular dilution of the 99% diatrizoate solution by extravascular water may explain this finding as well as the significantly longer rapid disposition phase and the slightly lower distribution volume of iohexol.

Contrast enhancement of the liver and blood. Nonionic versus ionic contrast media in the pig.

The contrast enhancement of low-osmolality (iohexol) and high-osmolality (diatrizoate) contrast media was compared in 18 pigs following intravenous bolus administration. Liver and blood attenuation and blood sample iodine concentration were measured during the first 3 minutes after injection. Iohexol produced a significantly higher contrast enhancement in the blood during the period from 0.5 to 3 minutes after injection. Diatrizoate produced a significantly higher contrast enhancement in the liver during the period from 9 to 30 minutes after injection. The greater contrast enhancement of iohexol during the acute phase should be advantageous in dynamic CT.

Angiography in leiomyosarcoma of the inferior vena cava--report of two cases.

Two patients with leiomyosarcoma of the suprarenal inferior vena cava are presented. In one case the tumour was misinterpreted as intrahepatic at angiography. In the second case an extrahepatic location was suggested after repeated angiography. The diagnosis should be borne in mind when a large hypovascular mass appears to be located centrally in the liver at coeliac angiography and when ultrasound examination has revealed its solid nature.

Hepatic telangiectasia in Osler's disease treated with arterial embolization. Report of 2 cases.

Hepatic hereditary telangiectasia in 2 females was treated with hepatic artery embolization. In one patient both peripheral and central arterial occlusion was performed; the patient died of massive gastro-intestinal bleeding for 2 months later. Autopsy showed extensive regions with necrosis in the right liver lobe. In the next patient only central occlusion of the right hepatic artery was performed and the arterio-venous shunting in the left liver lobe left remaining. After a long reconvalescence period the patient recovered completely. It is advocated to centrally occlude only that hepatic artery supplying the most affected parts of the liver in Osler's disease. Thus extensive necrosis with possible ensuing death may be avoided.

Aggressive treatment of acute limb ischemia due to thrombosed popliteal aneurysms.

OBJECTIVE: The absence of infra-popliteal runoff in patients with acute limb ischemia and thrombosed popliteal aneurysms carries a high risk of amputation. A combined treatment method involving thrombolysis and surgery is reported. MATERIAL AND METHODS: Information regarding six patients was reviewed. Ankle brachial indices and degree of ischemia were recorded. All patients underwent digital subtraction angiography. In five patients thrombus dissolution was achieved using a combination of mechanical and pharmacologic therapy. One patient was judged incapable of withstanding any delay in reperfusion and was treated with isolated limb perfusion using a thrombolytic agent. All patients underwent surgical revascularization. Follow-up (1-3 years) consisted of duplex examinations at 6 months and yearly thereafter. RESULTS: Five patients had no measurable ankle brachial index (ABI), while one patient had an ABI of 0.4. Initial angiography noted all patients to have no runoff in continuity to the pedal arch. Following thrombolytic therapy, an adequate bypass vessel was noted in all cases, with reconstitution of the plantar arch in five patients. Distal revascularizations included one peroneal, and five below knee popliteal arterial bypasses. Fasciotomies were performed in four of the six patients. There were no amputations. One patient developed a persistent foot drop. Two patients developed bypass grafts occlusions; one of which required therapy. CONCLUSION: The pre-operative use of thrombolytic therapy is a safe and effective method to achieve limb salvage in this patient population. Patients must be capable of withstanding an additional period of ischemia allowing for reconstitution of distal runoff. Isolated limb perfusion is of use when a delay to reperfusion cannot be tolerated.

[Functional control of the renal transplant via sequential computerized tomography. First results (author's transl)]. / Funktionskontrolle des Nierentransplantats durch Sequenz-CT. Erste Ergebnisse.

The enhancement of cortex medulla and arteria iliaca can be visualized separately, evaluated densitometrically and represented graphically by means of sequential computerized tomography of the renal transplant following intravenous contrast medium bolus injection. Since this enhancement performance is mainly dependent on perfusion, it is possible to determine the perfusion value of individual measurement areas. For example, a cortical defective perfusion, as is known in rejection, becomes evident as a flattening-out of the initial rise of cortex enhancement and can be distinguished from the largely normal type of curve obtained in acute tubular necrosis (ATN). The angiographically known prolonged "wash-out time' in rejection corresponds to a long-lasting corticomedullary density gradient. Despite restricted informative value because of the relatively small number of patients, it appears that sequential computerized tomography enables differentiation of postoperative anuria.

Computed tomography in the diagnosis of complications following renal allograft surgery.

Computed tomography was used in a consecutive series of 74 transplantations in the diagnosis of complications to renal allograft surgery. Thirty-nine peritransplant fluid collections were demonstrated, 13 of these were subjected to surgery. A diagnosis of the specific nature of the fluid collection was possible in cases of urine leakage and fresh hematomas. The method was sensitive in defining the size of the renal pelvis though differentiation between postrenal obstruction and large non-obstructed collecting system was not always possible. The cause of postrenal obstruction could be identified in 5 patients out of 10. Renal infarctions were diagnosed in 8 patients. Computed tomography seems to be a highly accurate method in the diagnosis of complications to renal allograft surgery. The method can be used independent of transplant function and the use of contrast medium is necessary only to verify urine leakage and infarction.

[The diagnosis of renal perfusion abnormalities by sequential CT (author's transl)]. / Diagnostik renaler Perfusionsstörungen durch Sequenz-CT.

Abnormalities of renal perfusion can be recognised more readily by sequential CT than by a plain CT scan or after "static" enhancement with contrast medium. Haemodynamically significant stenoses of the renal arteries and total, or partial, infarct can be diagnosed in this way. Intrarenal and capsular collaterals can be recognised by slow contrast accumulation in the infarcted area, or by the development of contrast in the sub-capsular portion of the cortex. Renal cortical necrosis is very well demonstrated by the absence of cortical perfusion; this is seen, for instance, in the DIC syndrome or during rejection after renal transplant.

Antimicrobial screening of selected medicinal plants from India.

From the Indian traditional medicines 78 plants were selected on the basis of their use in the treatment of infectious diseases. Different concentrations of 80% ethanol extracts were tested, using the agar dilution method, against four bacteria: Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa and, using the agar-well diffusion method, against two fungi: Candida albicans and Aspergillus niger. In the lowest tested concentration of 1.6 mg/ml, 10% of the plant extracts were active; 44% in a concentration of 6.25 mg/ml and 90% of the plant extracts were active against at least two bacteria in a concentration of 25 mg/ml. Only 13% of the plant extracts were active against at least one fungus in a concentration of 50 mg/ml.

In vitro screening of traditional medicines for anti-hypertensive effect based on inhibition of the angiotensin converting enzyme (ACE).

Traditional medicines reported to be used as anti-hypertensives or diuretics from different regions in the world (China, India and South America) have been investigated. The bioassay is based on inhibition of ACE, as measured from the enzymatic cleavage of the chromophore-fluorophore-labelled substrate dansyltriglycine into dansylglycine and diglycine. In total, 31 species have been investigated and the crude extracts from seven species inhibit the enzyme by more than 50%.

An ethnopharmacological survey for potential angiotensin converting enzyme inhibitors from Indian medicinal plants.

Plants used in different traditional systems of Indian medicine and some relatives/substitutes have been investigated for their angiotensin converting enzyme (ACE) inhibitory activity. They were selected on the basis of their usage as cardiotonics, diuretics and other uses related to the symptoms of hypertension. Out of the 73 species investigated, 22 showed more than 50% ACE inhibitory activity.

Was opium known in 18th dynasty ancient Egypt? An examination of materials from the tomb of the chief royal architect Kha.

Examination by microscopy, thin-layer chromatography, gas-liquid chromatography alone and combined with mass spectrometry, and radioimmunoassay methods of materials from the tomb of the ancient Egyptian chief royal architect Kha, who is believed to have died about 1405 BC, has shown that there is no morphine--and hence no opium--present. This finding casts doubt on the results of an earlier analysis. Tropane alkaloids are likewise absent. The significance of the present findings for the history of the opium poppy, Papaver somniferum L., in the eastern Mediterranean region is discussed. Evidence (chemical, botanical, artefactual, and linguistic) for the supposed presence of the opium poppy and opium in Egypt in the Late Bronze Age is briefly reviewed. These considerations and the negative outcome of the present analyses mean that the earlier reported finding can no longer be accepted as evidence.

In vitro screening of Indian medicinal plants for antiplasmodial activity.

Plants traditionally used in India to treat fever or malaria were examined in vitro for antiplasmodial properties against Plasmodium falciparum. Of 80 analysed ethanol extracts, from 47 species, significant effects were found for 31 of the extracts. These represent 23 different species from 20 families. Of the active species 20 were tested against P. falciparum for the first time. The following five species seems to be of special interest for further antimalarial studies, Casearia elliptica, Holarrhena pubescens, Pongamia pinnata, Soymida febrifuga, and Plumbago zeylanica.