The value of scintigraphic imaging with 99mTc-MIBI for the diagnosis of gliomas

Imagery is the only possibility of early glioma diagnosis. Both the gravity of the evolution and the bad prognostic, through all CNS tumors, justify the necessity to asses new techniques in order to improve glioma imagery. From this point of view, cerebral tomoscintigraphy has developed, its usefulness depending highly on the radiotracer tumoral specificity. One of these tracers, 99mTc MIBI, has been found to be uptake in glioma malignant cells, in relation with their viability and even malignity. In our study, -14 cerebral tomoscintigraphies have been realized on patients with glioma (initial or recurrent tumor), after 20 mCi 99mTc MIBI i.v. doses. The results are in correlation with the histologic glioma grade: high grade astrocytoma has positive images, but low grade astrocytoma doesn't. In conclusion 99mTc MIBI glioma tomoscintigraphies can be useful in their initial or recurrent diagnosis; the uptake tracer intensity being correlated with the histologic tumoral pattern, 99mTc MIBI SPECT could make possible a better localization of highest malignity tumoral points, in further biopsies.     

Usefulness and limitations of 99mTc-MIBI scintigraphy for detection of parathyroid lesions

To evaluate the usefulness of MIBI scintigraphy (MIBI) for parathyroid lesions, the detectability of lesions by MIBI was compared with that by Tl-Tc subtraction imaging, ultrasonography, CT and MRI in 56 histologically proved lesions. In neck lesions, ultrasonography (92%) and MIBI (85%) showed better detectability than those by the other three modalities. With MIBI, detectability was decreased for smaller parathyroid lesions that coexisted with thyroid disease. Among the five modalities, MIBI showed the highest detectability (88%) for ectopic or metastatic lesions. The smallest parathyroid lesions detected by MIBI were a parathyroid adenoma weighing 220mg and a parathyroid hyperplasia weighing 200mg. MIBI was thought to be more valuable for ectopic or metastatic parathyroid lesions.     

Gallbladder varices: diagnosis in children with portal hypertension on duplex sonography

Vascular dementia is actually considered as a ill-defined entity. The clinical and neuropathologic criteria of this multifactorial disorder remain uncertain. Although not widely accepted, the introduction of the concept of incomplete infarction in the brain can help to explain some particular types of vascular dementia. In the hypoxic-hypoperfusion dementia syndromes of cerebral cortex and white matter and in lacunar state dementia, which are the most common types of vascular dementia, areas of incomplete infarction co-exist with regions of complete infarction. Although initially rejected by early positron emission tomographic studies, it can now be demonstrated that these incomplete infarction areas reflect chronic ischaemia of the brain and that they are relevant to the pathogenesis of vascular dementia.     

Evaluation of brain tumor by 99mTc-MIBI: comparison study with 201Tl and predictivity of therapeutic effect

Spider silks are highly repetitive proteins, characterized by regions of polyalanine and glycine-rich repeating units. We have obtained two variants of the Spidroin 1 (NCF-1) silk gene sequence from Nephila clavipes. One sequence (1726 bp) was from a cloned cDNA, and the other (1951 bp) was from PCR of genomic DNA. When these sequences are compared with each other and the previously published Spidroin 1 sequence, there are differences due to sequence rearrangements, as well as single base substitutions. These variations are similar to those that have been reported from other highly repetitive genes, and probably represent the results of unequal cross-overs. We have also obtained 708 bp of sequence from pCR of genomic DNA from Araneus biocentenarius. This sequence shows considerable similarity to a dragline sequence (ADF-3) from A. diadematus, as well as Spidroin 2 (NCF-2) from N. clavipes. Minor but consistent differences in the repeating unit sequence between A. bicentenarius and A. diadematus suggest that concerted evolution or gene conversion processes are acting to maintain similarity among repeat units within a single gene.     

Surgical treatment of portal hypertension with ascites using ileovesicopexy under experimental conditions

Experiments conducted with albino rats have evidenced that under the effect of an atherogenic ration the level of lipids and cholesterol in the blood plasma and hepatic tissue and of sillac acids in the blood plasma increased. In the aortic intima the content of acid mucopolysaccharides was rising, this being attended by a concurrent swelling of the main interstitial substance and of the collagen fibers in the subendothelial layer. An addition of apple pectin or of cellulose to the atherogenic ration deferred the development of the mentioned changes.     

Changes in lymph vessels and portal veins in the portal tract of patients with idiopathic portal hypertension: a morphometric study

Little is known about the effects of the pathological process associated with idiopathic portal hypertension (IPH) on hepatic lymph vessels or lymph flow. We used morphometric analysis to examine IPH-associated changes in lymph vessels and branches of the portal vein, with use of immunohistochemical staining for alpha smooth muscle actin. We also quantitated these changes using an image analysis system. The study was conducted with use of liver wedge biopsy material from 10 patients with advanced IPH and 10 control samples from patients with gastric carcinoma without liver disease. The number of lymph vessels, identified by a lack of smooth muscle layer in the wall, and the ratio of the total area of these vessels to that of the portal tract were higher in IPH samples than in the control samples, but the ratio of the area of a single lymph vessel to that of the portal tract in IPH samples was not different from control samples. The number of portal vein branches, characterized by hypertrophy of the smooth muscle layer in IPH samples was not different from control samples. The ratio of the total area of these branches to that of the portal tract, and the ratio of a single portal vein branch to that of the portal tract, were lower in IPH samples than in the control samples. Our results suggest that these morphometric changes in IPH may be associated with a reduction in portal blood flow and increased lymph flow, and that the latter may in turn reduce the high portal vein pressure in idiopathic portal hypertension.     

Lipid changes in hepatic microsomes and its relationship to P-nitrophenol glucuronidation in an experimental model of portal hypertension

The liver is responsible for the most important metabolic pathway of non polar compounds. The aim of the present work was to study the p-nitrophenol glucuronidation and its relationship with lipidic composition of microsomal membrane in a model of hepatic portal hypertension and hepatocellular damage induced by monocrotaline. A global increment in liver microsomal phospholipids as well as changes in the phospholipid pattern (phosphatidylethanolamine and sphingomyelin increased up to 156 +/- 13 and 195 +/- 14% respectively) were detected in monocrotaline intoxicated rats when it were compared to control rats. The microsomal cholesterol content showed a decrease in monocrotaline intoxicated rats. (4.1 +/- 0.7 against 6.6 +/- 1.5 micrograms/mg of microsomal protein, in control rats). When p-nitrophenol activity was measured, Km from monocrotaline intoxicated rats was 0.137 mM, and Vmax was 2.9 nmol of p-nitrophenol/mg microsomal protein since in control group Km was 0.322 mM, and Vmax was 4.5 nmol of p-nitrophenol/mg microsomal protein. It is concluded that monocrotaline intoxicated rats showed a different behavior in the kinetics of p-nitrophenol UDP-glucuronyltransferase, as well as a different microsomal lipidic profile, when compared to control group.     

Significance of radioisotope bone marrow uptake on 99m technetium sulphocolloid scan in portal hypertension

A prospective study of 101 consecutive patients of portal hypertension was carried out to study the possible relationships between bone marrow activity on 99m technetium labelled sulphocolloid scan and severity of liver disease, etiology of portal hypertension and cirrhosis, as well as presence and extent of collateral circulation, including esophageal varices. The patients were divided into 4 etiological groups: alcoholic cirrhosis (ALD), (38) non-alcoholic cirrhosis (NALD) (35) non-cirrhotic portal fibrosis (NCPF) (14) and extrahepatic portal vein obstruction (EHPVO) (14). Patients of cirrhosis were categorised according to modified Child-Pugh's classification. Esophageal varices were graded endoscopically as (1) no varix (2) small varices (< 5mm) (3) large varices (> 5mm). All patients underwent radionuclide imaging using 99m Technetium labelled sulphocolloid and bone marrow activity was studied. Evaluation of portasystemic collaterals was done ultrasonically. We found that 16.6%, 44.6% and 72.72% patients with Child A, B and C cirrhosis respectively, had increased marrow activity (p < 0.05). There was no significant difference between marrow activity of patients with ALD (52.6%) and NALD (40%). None of the non-cirrhotic patients demonstrated bone marrow uptake of radioisotope. There was no significant difference between bone marrow uptake presence of lienorenal collaterals and presence or size of esophageal varices. We thus conclude the bone marrow activity on radioisotope scanning depends only on the severity of liver disease and does not vary a according to the etiology of cirrhosis, or presence and extent of portasystemic collaterals, including esophageal varices.     

Treatment of portal hypertension

Abnormalities of carbohydrate metabolism in hyperthyroid patients have been long noted. Elevated proinsulin level is considered as an early marker of B-cell impairment. Proinsulin levels in hyperthyroid patients decreased after antithyroid drug therapy. However, proinsulin in hypothyroid patients was only rarely reported, and the difference was only demonstrated after glucose stimulation-there was a greater response of proinsulin secretion after thyroxine therapy-and the basal fasting proinsulin level was not different after therapy. One of the reasons might be that the assay was not sensitive enough to detect the change of basal proinsulin levels in patients with hypothyroidism after therapy. A newly developed immunochemiluminometric assay of proinsulin was used to demonstrate that the suppressed proinsulin level increased after thyroxine therapy in hypothyroid patients (4.2 +/- 2.4 vs. 10.0 +/- 5.6 pmol/L, p < 0.05; n = 7). On the other hand, our study also confirmed that the proinsulin levels decreased in hyperthyroid patients after antithyroid therapy by methimazole (27.8 +/- 26.0 vs. 15.8 +/- 15.7 pmol/L, p < 0.05; n = 12). In conclusion, proinsulin increased in hypothyroid patients after thyroxine therapy and decreased in hyperthyroid patients after methimazole therapy. The results demonstrated there is a high correlation between thyroid function and B-cell function in hypothyroid as well as hyperthyroid patients.     

Prostacyclin production in acute, chronic, and long-term experimental portal hypertension

Curcumin, bis(4-hydroxy-3-methoxyphenyl)-1,6-diene-3,5-dione, is a yellow-orange dye derived from the rhizome of the plant Curcuma longa. Curcumin has demonstrated phototoxicity to several species of bacteria under aerobic conditions (Dahl, T. A., et al., 1989, Arch. Microbiol. 151 183), denoting photodynamic inactivation. We have now found that curcumin is also phototoxic to mammalian cells, using a rat basophilic leukemia cell model, and that this phototoxicity again requires the presence of oxygen. The spectral and photochemical properties of curcumin vary with environment, resulting in the potential for multiple or alternate pathways for the exertion of photodynamic effects. For example, curcumin photogenerates singlet oxygen and reduced forms of molecular oxygen under several conditions relevant to cellular environments. In addition, we detected carbon-centered radicals, which may lead to oxidation products (see accompanying paper). Such products may be important reactants in curcumin's phototoxicity since singlet oxygen and reduced oxygen species alone could not explain the biological results, such as the relatively long lifetime (t1/2 = 27 s) of the toxicant responsible for decreased cell viability.     

The evolution of surgery for extrahepatic portal hypertension

30 years' experience of elective surgical treatment of 600 patients with extrahepatic portal hypertension is summarized. Insufficient effectiveness of splenectomy in bleeding from varicose veins (VV) of the stomach and the esophagus (40% of relapses) is shown as well as frequent development (25%) of asplenic hemorrhagic thrombocytopenia. Partial esophagogastrectomy also has failed initial hopes due to severe agastric anemia which developed in 49.6% patients and relapses of erosion and ulcerogenous hemorrhage from the gastric stump (30%). Introduction of microsurgical methods, contemporary suturing material, usage of the jugular vein's segment for performing H-shape anastomoses enabled in the last decade to carry out porto-caval shunt using distal segments of superior mesenteric vein with diameter 5-9 mm and thus to increase the number of radical operations to thoroughly rehabilitate the patients, and to decrease postoperative mortality rate from 11.1% to 0.7% as well. Vascular anastomoses were not feasible, the operation of choice may be suturing of VV of the esophagus and the stomach with subsequent endoscopic sclerosis formation.     

Surgical management of portal hypertension

The surgical management of portal hypertension depends on the location of the obstruction. Suprahepatic obstruction is usually optimally treated by a surgical portacaval shunt. In extrahepatic obstruction the treatment should be sclerotherapy. For intrahepatic obstruction in emergency situations, sclerotherapy is the first choice, with portacaval systemic shunts or transjugular intrahepatic portal systemic stent shunt the second option. Liver transplantation in other situations should, if possible, be considered ahead of a portal diversion.     

Measurement of tumor vascular damage in mice with 99mTc-MIBI following photodynamic therapy

The clinical perfusion agent 99mTc-MIBI was used to monitor changes in tumor vascular perfusion (TVP) induced by Photofrin (PII)-mediated photodynamic therapy (PDT). BALB/c mice bearing an EMT-6 tumor on each hind thigh were given an intravenous injection of 1, 2 or 5 mg kg-1 PII. Twenty-four hours later, one tumor was illuminated (600-650 nm, 200 mW cm-2, 400 J cm-2) while the other served as a control. At various time intervals after PDT (0, 2 and 24 h) mice received an intravenous injection of 99mTc-hexakismethoxyisobutylisonitrile (MIBI) (0.18 MBq g-1) and were sacrificed 2 min later. The light-treated and the untreated tumors were then dissected, the radioactivity was counted and the percentage of the injected dose per gram of tumor (%ID g-1) was calculated as a measure of TVP. We observed that TVP is drug dose dependent, develops progressively with time post-PDT and is inversely related to PDT efficacy. Our data show that early tumor retention of 99mTc-MIBI is a simple method to assess TVP and vascular damage induced by PDT.     

In-home family-focused reunification: an experimental study

Intensive, in-home family-based services were employed in reunifying families separated by the placement of a child in out-of-home care. After a 90-day service period, 93% of the 57 families randomly assigned to receive the intensive treatment were reunited-compared to 28% of the 53 families in a control group who received routine out-of-home care services. Follow-up data were collected six and 12 months after the end of treatment. Estimates of outcomes suggest that the experimental treatment had a substantial impact on families and that treatment effects endured for upwards of 12 months following cessation of direct intervention services.     

Thickened gastric mucosal capillary wall: a histological marker for portal hypertension

We investigated the efficacy and safety of subcutaneous recombinant human erythropoietin (rHuEpo) in 25 children with chronic renal allograft dysfunction (13 girls, 12 boys, mean age 15.8 +/- 4.2 years) for a treatment period of 9-162 (median 43) weeks. rHuEpo was started once weekly at a dose of 105 +/- 25 U/kg per week in 16 children, twice weekly at a dose of 175 +/- 70 U/kg per week in 6 children, and three times weekly at a dose of 270 +/- 28 U/kg per week in 3 children. The hematocrit increased in 21 children from 23.2% +/- 3.1% to 33% +/- 3.1% within 7.2 +/- 4.9 weeks at a mean rate of 1.98%/week. The hematocrit increase and rHuEpo starting dose were linearly related (delta hematocrit/week = 0.8+0.08 U/kg per week, r = 0.44, P < 0.05). The maintenance dose was 74 +/- 23 (43-114) U/kg per week. Four children failed to reach the target hematocrit, most likely due to noncompliance. Seventeen recurrences of anemia ("anemic episodes") during rHuEpo therapy were identified in 12 children, mostly associated with acute or insidious deteriorations in graft function. There was no acceleration of progression of graft dysfunction with rHuEpo treatment. We conclude that subcutaneous rHuEpo at a single weekly dose of 100 IU/kg per week is highly effective in children with chronic graft dysfunction. Children who appear to be rHuEpo resistant or experience rHuEpo-resistant episodes should be assessed for noncompliance, changes in graft function since the last dosage adjustment, and blood loss, such as seen in dysfunctional uterine bleeding in adolescent girls.     

Vicryl mesh for repair of severely injured kidneys: an experimental study

We evaluated the efficacy of wrapping the kidney with semi-elastic Vicryl mesh for control of hemorrhage and preservation of renal function following grade III kidney lacerations (shattered kidney) in dogs in which nephrectomy was indicated clinically. Wrapping of fragmented kidneys resulted in prompt, sustained hemostasis and reapposition of the renal parenchyma. At an average of 80 days after injury the renal lacerations were well healed. The Vicryl mesh had been fully reabsorbed and there was considerably less scar tissue at the site of parenchymal rupture and neither perirenal or intrarenal abscess nor hematoma was found, grossly or microscopically. Among 12 dogs with grade III kidney lacerations, the mean ratio of the effective renal plasma flow (ERPF) in the affected kidney to the ERPF in the uninjured contralateral kidney was 0.53 +/- 0.22. The mean ratio of creatinine clearance of the injured kidney to that of the uninjured contralateral kidney was 0.41 +/- 0.23. Changes in the serum renin levels were not statistically significant following injury. Our results seem to confirm that simple and rapid surgical treatment of severely shattered kidneys using semi-elastic Vicryl mesh is possible. The method may also be suitable for uncontrollable bleeding during nonextirpative kidney surgery.