Weber-Christian disease presenting with proptosis: a case report

Weber-Christian disease (WCD) is a rare inflammatory disease of adipose tissue, which is characterized by painful cutaneous nodules and constitutional symptoms. Although any area of the body containing fat can be affected by WCD, the involvement of retrobulbar fat is uncommon and proptosis is a rare presenting manifestation. We report a case who presented with proptosis of the right eye which is accompanied by painful subcutaneous nodules, high fever and myalgia. Biopsies of retrobulbar tissue and suprapubic nodule showed lobular panniculitis with mixed cellular infiltration, mainly composed of histiocytes and lymphocytes. He responded well to high-dose glucocorticoid.

AAC-11 overexpression induces invasion and protects cervical cancer cells from apoptosis

To identify the genes involved in cervical carcinogenesis, we applied the mRNA differential display (DD) method to analyze normal cervical tissue, cervical cancer, metastatic lymph node, and cervical cancer cell line. We cloned a 491-bp cDNA fragment, CC231, which was present in metastatic tissue and cervical cancer cell line, but absent in normal cervical and cervical cancer tissues. The 491 bp cDNA fragment has 98% homology to the previously published sequence, AAC-11 (antiapoptosis clone 11). The levels of AAC-11 mRNA expressions in nine normal cervical and nine primary cervical cancer tissues were low. Its expression was higher in three metastatic tissues and five cervical cancer cell lines (HeLa, CaSki, SiHa, CUMC-3, and CUMC-6). Invasion of matrigel and adhesion to laminin by AAC-11 transfected CUMC-6 cells were increased by approximately 2-fold and 4-fold, respectively. Northern blot analysis showed that matrix metalloproteinase (MMP)-2 and membrane type 1 MMP (MT1-MMP) genes were found to be expressed in high levels in AAC-11-transfected cancer cells. But MMP-2 and MT1-MMP were not expressed in cells transfected with vector alone or wild-type cells. AAC-11-transfected cells expressed an elevated level of MMP-2 protein as assessed by immunoblotting. On the contrary, tissue inhibitor of MMP (TIMP-2) expression was detectable in cells transfected with vector alone or wild-type cells, respectively. Its expression was undetectable in AAC-11 transfected cells. In cervical cancer cells transfected with AAC-11, the expression of beta-catenin was up-regulated. These suggest that overexpressions of MMP-2 and MT1-MMP, loss of TIMP-2 expression, and up-regulation of beta-catenin by AAC-11 transfection may contribute to the development of cervical cancer invasion. AAC-11 gene transfection increased cervical cancer cell colonization. The effect of AAC-11 on cultured cervical cancer cells was associated with antiapoptotic process. Approximately 50% of the AAC-11 transfected cells in serum-free medium died after 2 weeks, compared to 1 week for vector alone or wild-type cells. These results suggest that AAC-11 may serve as a candidate metastasis-related and apoptosis-inhibiting gene in human cervical cancer.

Antioxidant and anti-tumor promoting activities of the methanol extract of heat-processed ginseng

Heat treatment of Panax ginseng C.A. Meyer at a temperature higher than that applied to the conventional preparation of red ginseng yielded a mixture of saponins with potent antioxidative properties. Thus, the methanol extract of heat-processed neoginseng (designated as 'NGMe') attenuated lipid peroxidation in rat brain homogenates induced by ferric ion or ferric ion plus ascorbic acid. Furthermore, the extract protected against strand scission in phiX174 supercoiled DNA induced by UV photolysis of H2O2, and was also capable of scavenging superoxide generated by xanthine-xanthine oxidase or by 12-O-tetradecanoylphorbol-13-acetate (TPA) in differentiated human promyelocytic leukemia (HL-60) cells. Topical application of NGMe onto shaven backs of female ICR mice 10 min prior to TPA, significantly ameliorated skin papillomagenesis initiated by 7,12-dimethylbenz[a]anthracene. Moreover, TPA-induced enhancement of epidermal ornithine decarboxylase (ODC) activity and ODC mRNA expression was abolished by a topical dose (0.68 mg) of NGMe. Likewise, TPA-induced production of tumor necrosis factor- in mouse skin was inhibited by NGMe pretreatment.

A simple and rapid method for cloning insect vitellogenin cDNAs

We describe a simple and rapid method for cloning insect vitellogenin (Vg) cDNAs. The method relies on the facts that insect Vg amino acid sequences can be aligned confidently along their entire lengths and that a short, highly conserved GL/ICG motif and up to nine cysteine residues that follow at conserved locations are present near the C-termini. An adaptor-ligated double-strand cDNA library is constructed from poly(A)+ RNA prepared from vitellogenic female fat body tissues using a commercial kit, and subjected to PCR with each of the degenerate nucleotide sequences for the GL/ICG motif and the adaptor sequence as primers. The PCR products (0.7-0.9 kb, representing the 3' portion) are cloned, the nucleotide sequences are determined, and the deduced amino acid sequences are aligned with the known insect Vg sequences starting from the GL/ICG motif. Gene-specific primers corresponding to the sequences near the 5'-termini of the initial clones and the adaptor sequence are employed to obtain the remaining 5' portion of the Vg cDNAs. The method was successfully applied to the bean bug Plautia stali (Heteroptera), revealing three Vg genes.

Eigenmode analysis of arbitrarily shaped two-dimensional cavities by the method of point-matching

In the proposed method, as in the boundary element method (BEM), a field problem is solved on its boundary along which nodes are distributed. The distinct feature of the proposed method is related to the fact that no interpolation functions between the nodes are required, so that the basic collocation method is employed to satisfy a given boundary condition. This approach reduces a large amount of numerical calculation induced due to the interpolation functions. Unlike the method of auxiliary sources (MAS), in the proposed method only the regular functions that have finite functional values everywhere including the origins are employed as basis functions. As a result, the proposed method does not need the auxiliary surface, the construction of which is a troublesome work because its form, dimension, shifting, etc. strongly influence the accuracy of the MAS. The eigenvalues calculated by the proposed method rapidly converge to the exact values thanks to the simplicity of the method. Moreover, the method gives mode shapes successfully without using the interpolation functions between the nodes. The efficiency and accuracy of the method are verified through several applications.

Correlation effect in activity measurement of 59Fe

Correlation effects due to the cascade transition of gamma-rays with gates on the relevant peaks have been studied in activity measurement of 59Fe using the bi-dimensional coincidence counting method. Extrapolation curves were obtained at three gamma gates of 1099.2 keV, 1291.6 keV, and that covering both photo-peaks by a computer discrimination method. Of these extrapolation curves, only that obtained at (950-1350) keV gamma gate shows a linear variation, but those of two single gamma gates are not linearly varied in the high efficiency region. This nonlinearity obtained at the gamma gate of 1099.2 keV photo-peak was caused by the correlation effects due to 1-3 coincidence relation via unobserved 192 keV gamma-ray transitions.

Artificial reproduction in a hymenopteran insect, Athalia rosae, using eggs matured with heterospecific yolk proteins and fertilized with cryopreserved sperm

Previtellogenic ovaries of Athalia rosae (Hymenoptera, Symphyta, Tenthredinidae) were transplanted into the adult female abdominal hemocoel of Athalia infumata (Symphyta, Tenthredinidae), Arge nigrinodosa (Symphyta, Argidae), and Pimpla nipponica (Apocrita, Ichneumonidae). The donor oocytes accumulated heterospecific yolk proteins and matured in the A. infumata host. On average, six mature oocytes were obtained per transplanted ovary. In contrast, the donor oocytes accumulated a limited amount of yolk but did not mature in the Ar. nigrinodosa host and did not even accumulate yolk in the P. nipponica host. The eggs that matured in the A. infumata host were injected with cryopreserved A. rosae sperm that had been taken from adult male seminal vesicles and stored at -80 degrees C. Fertilization, as confirmed by the use of visible marker mutations, was achieved and a fraction of the injected eggs developed into fertile female adults.

Development of a three-dimensional data acquisition method for standardization of beta-emitting nuclides

We have developed a three-dimensional data-acquisition system with which pulse heights from an array of detectors can be multi-scaled with dwell times as short as 31 ns. The main part of the system consists of three ADCs of SAR (Successive Approximation Register) type, a 32 MHz oscillation clock and DRAM (Dynamic Random Access Memory) of 192 Mbyte capacity. The clock time is determined by count the clock pulse generated by 28 bits synchronous counter. Both the pulse height and the time information are stored at an array of DRAM, of 40-bits width, 12-bits for pulse height and 28-bits for clock time. The technique is particularly suitable for experiments such as both double and triple coincidence distributions are required. Virtues of the method are demonstrated by measuring the activity of 14C with a 3-PM liquid scintillation counting system. The computer discrimination together with the MCTS (multi-channel time scaling) technique is applied for efficiency variation method in the analysis.

Amyloid-beta injection in rat amygdala alters tau protein but not mRNA expression

Previously we demonstrated local and distant changes in tau protein immunoreactivity reminiscent of those seen in Alzheimer's disease (AD) following a unilateral injection of amyloid-beta (Abeta)(25-35) into the rat amygdala. To explore the relevance of these findings to AD, we compared the effects of Abeta(1-42) to those of Abeta(25-35). Injections of both Abeta(1-42) and Abeta(25-35) into rat amygdala resulted in increased tau-2 immunolabeling in neurons. To determine whether these alterations were due to changes in the expression of tau, we measured tau protein expression by Western blotting and tau mRNA isoform expression by the reverse transcription-polymerase chain reaction in the amygdala, hippocampus, and cerebellum following a unilateral injection of Abeta(25-35) or vehicle into the amygdala. The levels of tau proteins were increased bilaterally in the amygdala of Abeta(25-35)- compared to vehicle-treated animals 8 and 16 days following treatment. The molecular weights of tau proteins were decreased in the Abeta(25-35)-treated (59-69 kDa) compared to the vehicle-treated (67-72 kDa) animals 8 days following treatment. There were no changes in tau mRNA expression in any brain region examined. In this model, just as in AD, there is an increase in tau protein levels without a change in tau mRNA expression, suggesting that Abeta peptides may influence tau protein stability in both the rat and the human brain.

Neuroprotection due to irrigation during bipolar cautery

OBJECTIVE

To test whether irrigation during bipolar cautery confers thermoprotection from neuronal injury.

DESIGN

A rat animal model (15 rats for each treatment group) was used to test the thermoprotective effects of irrigation during bipolar cautery. In this model, the sciatic nerve was exposed, and a 1-second stimulus was applied using bipolar cautery forceps at 40 or 20 W placed directly on the nerve in the presence or absence of simultaneous irrigation. The effects of cautery were determined on the basis of clinical gait analysis by means of the Sciatic Functional Index, temperature response, and neuropathological findings.

RESULTS

The degree of paresis was reduced with irrigation. Neuropathological examination of the sciatic nerve after cautery showed significant axonal loss (more small than large fibers) with concomitant demyelination, which was partially inhibited by irrigation (chi2; P = .04). The mechanism of thermoprotection by irrigation was not the result of a reduction in the temperature spike that followed cautery, but resulted from a reduced temperature response during the 15 seconds that followed 40- or 20-W stimulation with bipolar cautery.

CONCLUSIONS

Simultaneous irrigation and bipolar cautery enhance temperature recovery to basal levels and protect the peripheral nerve from the effects of cautery.

An improved optical technique for monitoring plant cell concentration

 An improved optical method was developed to determine cell weight concentrations using a micro-plate reader. Light absorbance was measured by a vertical light beam, which can minimize the cell settling effect found in traditional optical measurements with a horizontal light beam. The use of well plates not only requires very small sample sizes, but also handles a large number of samples at the same time. Absorbance measurements were linearly related to cell weight over the full range of batch culture growth.

Vitellogenin of the cicada Graptopsaltria nigrofuscata (Homoptera): analysis of its primary structure

We cloned and sequenced the cDNA of vitellogenin (Vg) from the cicada Graptopsaltria nigrofuscata (Homoptera). The deduced amino acid sequence of 1987 residues (including 16 residues for a putative signal peptide) was obtained. The pro-Vg was cleaved into two subunits between residues 379 and 380 following a consensus RXXR cleavage site sequence, secreted as S-Vg (apparent molecular weight 43 kDa) and L-Vg (200 kDa), sequestered, and stored in the egg as two vitellins (Vns), S-Vn and L-Vn, with similar respective molecular weights. There was a single long serine-rich stretch closely following the cleavage site. The entire amino acid sequences of the Vgs from the eight insects so far reported could be aligned confidently. The presence of subdomains I-V (areas of relatively high amino acid conservation) and of 10 cysteines at conserved locations at the C-terminus, noted previously among insect Vgs, were confirmed. Antisera raised against G. nigrofuscata S- and L-Vn cross-reacted with the S- and L-Vg/Vn, respectively, of all three other cicada species examined. Another major egg protein (170 kDa) unrelated to Vg/Vn, was also detected in all species examined.

Solitary necrotic nodules of the liver mimicking hepatic metastasis: report of two cases

We present two cases of solitary necrotic nodules of the liver which on radiologic images mimicked hepatic metastasis. Solitary necrotic nodule of the liver is a rare but benign entity which histopathologically consists of an outer fibrotic capsule with inflammatory cells and a central core of amorphous necrotic material. The lesion was seen on contrast-enhanced CT as an ovoid-shaped hypoattenuating nodule; on CT during hepatic arteriography as enhancing nodule; on intraoperative US as a target-appearing hypoechoic nodule; on T2WI as a hyperintensity nodule, and on dynamic MR as a subtle peripheral enhancing nodule. Although the radiologic features are not specific, solitary necrotic nodule of the liver should be included in the differential diagnosis of hepatic metastasis.

The effects of blood on rapid urease testing for Helicobacter pylori in mucosal biopsies from the gastric antrum

BACKGROUND

While the eradication of Helicobacter pylori in patients with bleeding peptic ulcer disease (PUD) decreases the rate of ulcer re-bleeding, the sensitivity of the rapid urease test (RUT) for H. pylori diagnosis is lower in this setting. The aim of this study was therefore to determine if exposing a gastric biopsy specimen to blood before its use in the RUT (CLOtest) could account for these findings.

METHODS

In patients undergoing endoscopy for the evaluation of dyspepsia gastric mucosal biopsies were obtained for H. pylori diagnosis (RUT, microbiology, and histology). Mucosal biopsies from each patient were also exposed to blood for 15, 30 and 45 minutes before use in the RUT.

RESULTS

Using a combination of diagnostic tests (histology, microbiology and routine CLOtest) as the 'gold standard', the sensitivity, specificity, positive predictive value and negative predictive value of the CLOtest remained above 90% despite prior exposure of the gastric biopsy specimen to blood, and these values were not significantly different from the performance characteristics of the CLOtest processed in a routine manner.

CONCLUSION

The exposure of gastric mucosal biopsy specimens to blood alone is not the explanation for the reduced sensitivity of the RUT in patients with bleeding peptic ulcers.

Delayed colon perforation after palliative treatment for rectal carcinoma with bare rectal stent: a case report

In order to relieve mechanical obstruction caused by rectal carcinoma, a bare rectal stent was inserted in the sigmoid colon of a 70-year-old female. The procedure was successful, and for one month the patient made good progress. She then complained of abdominal pain, however, and plain radiographs of the chest and abdomen revealed the presence of free gas in the subdiaphragmatic area. Surgical findings showed that a spur at the proximal end of the bare rectal stent had penetrated the rectal mucosal wall. After placing a bare rectal stent for the palliative treatment of colorectal carcinoma, close follow-up to detect possible perforation of the bowel wall is necessary.

Expression of the bile salt export pump is maintained after chronic cholestasis in the rat

BACKGROUND & AIMS

This study assessed the expression of the recently identified adenosine triphosphate-dependent bile salt export pump and the functional ability to excrete bile salts in cholestatic models in the rat.

METHODS

The effects of common bile duct ligation, endotoxin, and ethinylestradiol on bile salt export pump messenger RNA levels, protein expression, and tissue localization were determined. Changes in the expression of 3 other hepatocyte membrane transporters (Na(+) taurocholate cotransporter, multispecific organic anion transporter, and P-glycoprotein) were also determined for comparison. Functional assessment of bile salt excretion was determined after bile duct ligation.

RESULTS

Expression of the bile salt export pump was diminished but relatively preserved compared with other membrane transporters. Tissue localization of the bile salt export pump persisted at the canalicular domain in all 3 models. In contrast, expressions of the Na(+) taurocholate cotransporter and multispecific organic anion transporter were more profoundly diminished. P-glycoprotein levels increased severalfold with common bile duct ligation but were unchanged with either endotoxin or ethinylestradiol. The capacity to excrete bile salts was relatively maintained 3 and even 14 days after bile duct ligation.

CONCLUSIONS

Alterations in expression of the bile salt export pump may account for the functional alterations of bile salt secretion observed in cholestasis. However, relative preservation of expression is associated with persistent bile salt excretion and may lessen the extent of liver injury produced by bile salt retention.

Elevated transglutaminase-induced bonds in PHF tau in Alzheimer's disease

Transglutaminase-induced epsilon-(gamma-glutamyl)lysine bonds covalently cross-link and polymerize peptides into insoluble high molecular weight protein aggregates resistant to degradation and proteolytic digestion. We investigated the hypothesis that excessive deposition of epsilon-(gamma-glutamyl)lysine bonds is a neuropathological mechanism which induces the polymerization of tau protein into stable aggregates leading to the formation of paired helical filaments (PHFs) which deposit into neurofibrillary tangles in Alzheimer's disease (AD) brain. We demonstrate a significant (45%) elevation in epsilon-(gamma-glutamyl)lysine cross-links in AD cortex as compared to control cortex. In vivo, PHF tau, and high and medium molecular weight neurofilament proteins have significantly greater cross-linking by epsilon-(gamma-glutamyl)lysine bonds in AD brains as compared to controls. The cross-linking of PHF tau occurs both intra-molecularly and inter-molecularly. The inter-molecular cross-linking of tau could account for the formation of high molecular weight tau polymers. These results suggest that transglutaminase-induced cross-linking of tau protein could play a role in the formation and stabilization of neurofibrillary tangles. Inhibition of transglutaminase-induced cross-linking may therefore, provide a novel strategy for the treatment of AD.

Modification of EWS/WT1 functional properties by phosphorylation

In many human cancers, tumor-specific chromosomal rearrangements are known to create chimeric products with the ability to transform cells. The EWS/WT1 protein is such a fusion product, resulting from a t(11;22) chromosomal translocation in desmoplastic small round cell tumors, where 265 aa from the EWS amino terminus are fused to the DNA binding domain of the WT1 tumor suppressor gene. Herein, we find that EWS/WT1 is phosphorylated in vivo on serine and tyrosine residues and that this affects DNA binding and homodimerization. We also show that EWS/WT1 can interact with, and is a substrate for, modification on tyrosine residues by c-Abl. Tyrosine phosphorylation of EWS/WT1 by c-Abl negatively regulates its DNA binding properties. These results indicate that the biological activity of EWS/WT1 is closely linked to its phosphorylation status.

Antisense oligodeoxynucleotide of glyceraldehyde-3-phosphate dehydrogenase gene inhibits cell proliferation and induces apoptosis in human cervical carcinoma cell lines

Tumor cells characteristically exhibit an increased rate of glycolysis. A higher level of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA was found in human uterine cervical cancers. This study was designed using GAPDH antisense oligodeoxynucleotide (ODN) phosphorothioate (PS) to evaluate how alterations of GAPDH expression in human cervical carcinoma could influence growth inhibition and induction of apoptosis. Northern blot analyses revealed that the levels of GAPDH gene expression were strongly elevated in three cervical carcinoma cell lines (HeLa, CUMC-3, and CUMC-6) compared with normal cervical tissue. Reverse transcription-polymerase chain reaction (RT-PCR) showed that expression of the GAPDH gene was inhibited by 10 microM of GAPDH antisense ODN in all three cell lines. Western blot analysis showed that the levels of GAPDH protein were decreased or absent after GAPDH antisense ODN treatment for 12 days in cultured cervical carcinoma cell lines. Cervical carcinoma cell lines exposed to GAPDH antisense ODN showed reduced cellular proliferation, which was accompanied by reduced colony-forming efficiency. This effect of GAPDH antisense ODN on cultured carcinoma cells was associated with the apoptotic process, including increased DNA fragmentation. These results suggest that future gene therapy using antisense ODN directed against cervical cancer-specific GAPDH mRNA might be another therapeutic tool against human uterine cervical carcinomas.

4-Aminopyridine antagonizes the acute relaxant action of metformin on adrenergic contraction in the ventral tail artery of the rat

The ability of metformin (MF) to acutely relax phenylephrine (PE)-induced contraction in the isolated rat tail artery is reported to be accompanied by repolarization of the arterial smooth muscle cell (SMC) membranes. These membranes contain potassium (K) channels which if opened could mediate such repolarization and resultant relaxation. We have shown that the acute relaxation of rat tail arterial tissue rings by graded levels of MF > or = 0.24 mmol/L is markedly antagonized by a high concentration of tetraethylammonium (TEA; 10 mmol/L) which nonselectively inhibits nearly all K channels. Thus, we tested effects of more selective inhibitors of K channels in the same tissue. We also tested MF for relaxation of contractions induced by high levels of extracellular K. To avoid confounding variables, we also conducted these tests in arterial rings in which endothelium and sympathetic nerve endings had been removed. In the absence of K channel inhibition, half-maximal PE-induced contractions were rapidly relaxed by all levels of MF with an EC50 of 1.7+/-0.2 mmol/L (n=8 rings). 1 mmol/L 4-aminopyridine (4AP) which only inhibits voltage-operated and ATP-sensitive K channels markedly antagonized this relaxation, shifting the EC50 for MF to 7.5+/-0.7 mmol/L (n=8; p < 0.05). TEA at 1 mmol/L (which only inhibits calcium-activated K channels), barium at 20 micromol/L (which only inhibits inward rectifier K channels) and glyburide at 5 micromol/L (which only inhibits ATP-sensitive K channels) did not alter this relaxation. Finally, MF failed to relax contractions produced by elevations of extracellular K to levels high enough to abolish the K gradient across arterial SMC membranes. Thus, acute relaxation of rat tail arterial smooth muscle by MF may be dependent on the transmembrane K gradient and mediated at least in part by specific activation of K efflux through 4AP-sensitive voltage-dependent K channels in arterial SMC membranes.

Inhibitory effects of chlorophyllin on 7,12-dimethylbenz[a]anthracene-induced bacterial mutagenesis and mouse skin carcinogenesis

Chlorophyllin (CHL), a water-soluble derivative of chlorophyll, has been used for the treatment of several abnormal human conditions without apparent toxicity. Recent studies have revealed that CHL has the excellent chemopreventive potential. In the present investigation, we have found the inhibitory activities of CHL against 7,12-dimethylbenz[a]anthracene (DMBA)-induced mutagenesis in Salmonella typhimurium TA100 and also on DMBA-initiated and 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-promoted mouse skin tumor formation. The incidence and the multiplicity of skin tumors were not significantly decreased in mice by a single topical application of CHL prior to the DMBA treatment, but there was a marked suppression of papillomagenesis in mice treated with CHL during the promotional stage. Furthermore, the formation of DMBA-induced papillomagenesis was reduced in all mice that had received CHL for 6 weeks following treatment with TPA for 6, 18 and 24 weeks. These results indicate that CHL can inhibit both tumor promotion and the progression of papillomagenesis in the two-stage mouse skin carcinogenesis induced by DMBA and TPA.

Cervical thymic cyst in the elderly: a case report

Cervical thymic cyst is uncommon and usually occurs in the first and second decades. Cervical thymic cyst after the third decade is so rare that it is very difficult to diagnose in spite of its typical location. We present a rare case of cervical thymic cyst in the lower left - anterior of the neck in a 50-year-old woman. It showed well-defined, anechoic cyst on ultrasonography and non-enhancing low attenuation mass on CT. A typical anatomic relationship was noted between the mass and carotid sheath.

Embolization of superior mesenteric artery branches in dogs. Ischemic bowel changes depend on location of vessel occlusion and embolic materials

OBJECTIVE

To evaluate the degree of ischemic changes of the small intestine after arterial embolization of proximal or distal arteries with Gelfoam particles and coils in dogs.

METHODS

Superselective arterial embolization in 18 dogs was performed using a coaxial catheter system. Gelfoam occlusion of the proximal level of ileal or jejunal arteries was performed in four dogs (group A). Gelfoam occlusion of the distal level was performed in four dogs (group B). Coil occlusion of the proximal level was performed in five dogs (group C). Coil occlusion of the distal level was performed in five dogs (group D). All 18 dogs were killed 1 day after the procedure. Gross and microscopic findings were evaluated.

RESULTS

The embolizations were successful in all dogs. In group B, significant mucosal destruction, lymphocyte proliferation of the submucosa and mucosa, and diffuse swelling in all layers of the intestine were found in all four dogs. Three revealed diffuse ischemic changes and one showed focal ischemic changes. In groups A and C, all the layers of the intestine were intact and did not show any ischemic changes. In group D, one dog showed erosion of a small portion of mucosa and lymphocytic infiltration. The other dogs showed nonspecific findings in all layers of the intestine.

CONCLUSIONS

Proximal embolization with Gelfoam and coils as well as distal embolization with coils did not cause ischemia. However, ischemic changes in the intestinal wall could be observed after distal embolization with Gelfoam.

Determinants of mechanical properties in the developing ovine thoracic aorta

We previously reported changes in mechanical properties and collagen cross-linking of the ovine thoracic aorta during perinatal development and postnatal maturation, and we now report changes in biochemical composition (elastin, collagen, and DNA contents per mg wet wt) over the same developmental intervals. A comparison of results from the present and previous studies has yielded novel and important observations concerning the relationship between aortic mechanics and composition during maturation. Developmental changes in aortic incremental elastic modulus at low tensile stress (E(low)) closely followed changes in relative elastin content (i.e., per mg wet wt). An 89% increase in E(low) during the perinatal period was associated with a 69% increase in relative elastin content, whereas neither variable changed during postnatal life. Incremental elastic modulus at high tensile stress (E(high)) did not change during the perinatal period but increased 88% during postnatal life. This pattern closely paralleled changes in collagen cross-linking index, which did not change perinatally but almost doubled postnatally. In contrast, relative collagen content (per mg wet wt) increased only slightly from fetal to adult life, a trend that was unrelated to aortic mechanics. Substantial, progressive decreases in measures of wall viscosity (pressure wave attenuation coefficient and viscoelastic phase angle) from fetal to adult life followed the pattern observed for relative DNA (smooth muscle cell) content (per mg wet wt). Our findings suggest that accumulation of elastin per milligram wet weight contributes most to developmental changes in E(low), change in collagen cross-linking is the primary determinant of developmental changes in E(high), and cell accumulation contributes most to developmental changes in wall viscosity.