Relationship of vacA genotypes of Helicobacter pylori to cagA status, cytotoxin production, and clinical outcome

BACKGROUND

Mosaicism in vacA alleles with three distinct families of vacA signal sequences (s1a, s1b and s2) and two distinct families of middle region alleles (m1 and m2) has been reported. It was suggested that the vacA s1a genotype was closely associated with duodenal ulcer disease and with high cytotoxin production. The aim of this study was to evaluate the role of vacA genotyping with respect to gastric inflammation and injury, cytotoxin activity, and clinical presentation.

METHODS

H. pylori from patients with gastritis, peptic ulcer disease, or gastric cancer were characterized by vacA typing by polymerase chain reaction (PCR) and DNA sequencing. In vitro cytotoxin activity was assessed by vacuolation assay using Vero cells as well as with Hela cells.

RESULTS

Four hundred ninety-one strains were tested. vacA genotype s1a/m1 was present in more than 95% of strains independent of presentation with gastritis, peptic ulcer, or gastric cancer. No vacA genotype was associated with high average cytotoxin activity. The s2/m2 isolates had low or absent cytotoxin activity. All cagA negative strains (n = 18) were s1a strains and both s2/m2 strains were cagA positive. One strain that was a recombinant of m1 and m2 strains was identified and had low cytotoxin activity. The nucleotide and amino acid sequences between original m1 strains and Japanese m1 strains (new m1 strains) were about 85% and 81%, respectively. Strains with the new m1 genotype had nucleotide and amino acid sequences similarity of more than 96%. There was no difference in cytotoxin activity between strains with the Western type m1 and the new type m1 genotype.

CONCLUSION

In this as in other reported studies ( approximately 1500 patients overall) vacA genotype was strongly but not exclusively associated with the presence of cagA. Overall, the studies did not support a role for vacA genotyping in relation to cytotoxin activity, virulence, histologic finding, or risk of a particular H. pylori disease. vacA genotype s1 is likely to be a surrogate marker for the presence of the cag pathogenicity island.

Characterization of a cDNA homologous to carotenoid-associated protein in citrus fruits

A cDNA (CitPAP) homologous to a gene encoding for Cucumis sativus carotenoid-associated protein (CHRC) has been isolated from satsuma mandarin (Citrus unshiu Marc.). Unlike ChrC whose expression was limited only in mature fruits (containing chromoplasts), CitPAP transcripts were detected in all the tissues examined including fruits, flowers and leaves. In this respect, CitPAP was rather close to a gene encoding for pepper plastid-lipid-associated protein (PAP), which exhibits ubiquitous expression in bell pepper organs containing chloroplasts or chromoplasts. CitPAP, however, differed from PAP in the magnitude and pattern of RNA accumulation. These results might indicate a novel function of CitPAP.

Phacoemulsification of dislocated lens and suture fixation of intraocular lens using a perfluorocarbon liquid

The objective was to describe a new surgical technique to manage a posteriorly dislocated crystalline lens. Four patients with posteriorly dislocated lenses were studied. Two patients had dislocated lenses secondary to trauma, 1 had undergone retinal detachment surgery, and 1 had an idiopathic lens dislocation. Pars plana vitrectomy was carried out on all 4 eyes, followed by an injection of perfluoro-n-octane to float the lens off the retina. The lens was phacoemulsified through a limbal incision, and an intraocular lens was positioned in the ciliary sulcus with suture fixation. Perfluoro-n-octane was replaced by a balanced salt solution. Postoperative visual acuity ranged from 1.0-1.5. Transient choroidal detachment and hypotony were observed in 3 eyes in the early postoperative period. Postoperative ocular hypertension was noted in 2 eyes and was well-controlled with topical antiglaucoma agent. These results indicate that limbal lensectomy of a posteriorly dislocated lens using perfluorocarbon liquids is a beneficial and relatively safe method.

Paradoxical response to valproic acid in a patient with a hypothalamic hamartoma

OBJECTIVE

To report a patient who developed the paradoxical effect of increasing electrical seizure activity and confusion with initiation of valproic acid therapy.

CASE SUMMARY

A 25-year-old African-American woman with a hypothalamic hamartoma had an electroencephalogram (EEG) that demonstrated frequent bursts of generalized spike and wave activity. The prevalence of spike and wave activity increased dramatically and the patient became increasingly somnolent as valproic acid was added to carbamazepine and phenobarbital therapy. Her EEG and mental status changes resolved when the valproic acid was discontinued. There was a strong positive correlation between the prevalence of spike and wave activity and the valproic acid concentration, but not between spike and wave activity and the concentrations of carbamazepine or phenobarbital.

DISCUSSION

Although this is a complex case, it is clear that the addition of valproic acid produced an increase in spike and wave activity. Possible mechanisms and pathophysiologic significance of this paradoxical effect are discussed in light of the differences between this epileptic syndrome and the primary generalized epilepsies.

Direct evidence that LTC4 and LTB4 but not TXA2 are involved in asthma attacks in children

There are substantial numbers of reports showing that leukotrienes (LTs) play important roles in adult asthma. No definite evidence has been demonstrated that LTs are involved in asthma attacks in children, although it is highly expected. In this report, we demonstrated that the levels of LTB4 and LTC4 but not thromboxane B2 (TXB2), a stable metabolite of TXA2, were significantly elevated in the bronchoalveolar lavage fluid, which was obtained from intubated and mechanically ventilated children with severe asthma attacks. This is direct evidence that LTB4 and LTC4 predominantly participate in asthma attacks in pediatric patients.

Quantitative assessment of macular edema with retinal vein occlusion

PURPOSE

To evaluate the retinal thickness analyzer, a new image analyzer involving laser-slit biomicroscopy, for quantitative assessment of retinal thickness in patients with macular edema secondary to retinal vein occlusion.

METHODS

Fifty-eight patients (central retinal vein occlusion, 22 eyes; branch retinal vein occlusion, 36 eyes) with a clinical diagnosis of macular edema associated with retinal vein occlusion were evaluated. Retinal thickness analysis was performed with the retinal thickness analyzer. A green helium-neon laser slit directed into the eye was scanned to generate optical cross-sections of the retina. Images were analyzed by an automated software algorithm, and a detailed map of the retinal thickness was obtained.

RESULTS

Laser-slit images obtained with the retinal thickness analyzer in patients with macular edema associated with retinal vein occlusion disclosed intraretinal changes such as retinal edema, cystoid spaces, and hemorrhages. Linear regression analysis showed a significant relationship between the macular thickness in the central fovea and corrected visual acuity reported on a logMAR scale (P = .002, adjusted R2 = 0.40 in central retinal vein occlusion; P = .002, adjusted R2 = 0.34 in branch retinal vein occlusion).

CONCLUSION

We confirmed the capability of the retinal thickness analyzer to provide rapid and precise evaluation of macular thickening in patients with retinal vein occlusion.

Traumatic cataract with a ruptured posterior capsule from a nonpenetrating ocular injury

An 11-year-old boy had posterior lens capsule rupture resulting from a nonpenetrating (blunt trauma) injury to the eye. A rapidly developing cataract required pars plana lensectomy. This report suggests that posterior capsule rupture may occur secondary to blunt trauma and progressive cataract formation after posterior capsule rupture may require surgery soon after the injury.

Characterization of gene repertoires at mature stage of citrus fruits through random sequencing and analysis of redundant metallothionein-like genes expressed during fruit development

We carried out a random sequencing of cDNA library derived from mature citrus fruit (Citrus unshiu Marc.) for identifying the gene repertoires expressed at the mature stage. Among 297 clones analyzed, 195 cDNA clones (65.7%) were putatively identified to previously characterized genes with optimized (OPT) scores of >/=200 through a homology search to DNA database, whereas 102 clones (34.3%) resulted in low OPT scores (<200) and did not show any significant sequence identity with previously published genes. Among them, clones homologous to metallothionein (MT)-like genes appeared 62 times, being mostly redundant, and accounting for about 20.9% of the total 297 clones. To gain a better understanding of the MT-like genes, two types of cDNA clones were isolated. One clone (CitMT36) resembled the type 2 MT gene containing Cys-X-Cys motifs in both N- and C-terminal, but the consensus sequence in the N-terminal domain, Cys-Cys and Cys-X-X-Cys was modified in CitMT36 to X-Cys and Cys-X-X-X, respectively. We suggest that these form a 'novel type 2' group of MT-like clones. The other clone (CitMT45) showed homology to type 3 MT-like genes, which have been found in mostly fruit tissues so far. By Southern blot analysis, both clones showed one or two bands, suggesting that both CitMT36 and CitMT45 are present in single or a few copies in the citrus genome. Transcripts of CitMT36 were evenly detected in all tissues examined, whereas those of CitMT45 were detected primarily in fruit during the developmental phase. Neither of the MT-like genes was induced in leaves by Zn and Cu. Collectively, MT-like genes from citrus would be regulated differentially depending on the fruit developmental stage and organs, indicating a change in their expression under the different physiological and molecular environment of fruit cells.

Chemokines in the gastric mucosa in Helicobacter pylori infection

BACKGROUND

Although chemokines have been suggested to play an important role in Helicobacter pylori associated gastritis, few studies have investigated the role of chemokines other than interleukin 8 (IL-8) in gastric mucosa.

AIMS

To investigate the expression and production patterns of various chemokines using gastric biopsy specimens.

METHODS

In 192 patients, expression patterns of C-X-C chemokines (IL-8 and growth regulated alpha (GRO alpha)) and C-C chemokines (regulated on activation, normal T cell expressed and presumably secreted (RANTES), monocyte chemotactic and activating factor (MCAF), macrophage inflammatory protein 1 alpha (MIP-1 alpha), and MIP-1 beta) were examined using reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA). cagA gene was identified using PCR.

RESULTS

H pylori infection was associated with increased rates of expression of mRNA for IL-8, GRO alpha, RANTES, and MIP-1 alpha and with increased levels of mucosal IL-8 and GRO alpha. IL-8 and GRO alpha levels correlated with the density of H pylori in both the antrum and corpus. The levels of these chemokines correlated with cellular infiltration in the antrum but not the corpus. cagA gene positive H pylori infection was associated with increased rates of expression of mRNA for IL-8 and GRO alpha and with increased levels of these chemokines.

CONCLUSION

H pylori infection is associated with increased expression rates and production of C-X-C chemokines (IL-8 and GRO alpha), but not with increased production of C-C chemokines. Although H pylori infection is associated with increased C-X-C chemokines in the antrum and corpus, there is a difference in the inflammatory response between these two areas of the stomach.

Inhibition of leukotriene synthesis by terfenadine in vitro

To determine the inhibitory mechanisms of terfenadine on the synthesis of leukotriene C4 (LTC4), an important mediator in allergic diseases, we evaluated the action of terfenadine on the IgE-dependent production of LTC4 in rat basophilic leukaemia 2H3 cells. Rat IgE-loaded cells were stimulated with anti-IgE in the presence or absence of various concentrations of terfenadine and the level of LTC4 released into the medium was measured by performing a specific radio immunoassay. Terfenadine inhibited the synthesis of LTC4 to 67.2% at a concentration of 5 microg/ml. LT synthesis was directly suppressed by inhibition of 5-lipoxygenase (5-LO) through calcium ion-independent mechanisms, and was also possibly suppressed by inhibition of cytosolic phospholipase A2 and 5-LO by blocking the influx of intracellular calcium ion that was initiated by IgE-related stimulation.

Induction of various cytokines and development of severe mucosal inflammation by cagA gene positive Helicobacter pylori strains

BACKGROUND

Helicobacter pylori strains possessing the cagA gene are thought to induce interleukin 8 (IL-8) in gastric mucosa. However, it is still unclear whether a relation exists between the cagA gene and the expression patterns of cytokines other than IL-8.

AIMS

To investigate the relation between the cagA gene and the production of various cytokine proteins using an enzyme linked immunosorbent assay (ELISA).

PATIENTS AND METHODS

In 184 patients, the cagA gene was detected by polymerase chain reaction (PCR), and levels of production of IL-1 beta, IL-6, IL-7, IL-8, IL-10, and tumour necrosis factor alpha (TNF-alpha) in antral biopsy specimens were measured by ELISA.

RESULTS

Mucosal levels of IL-1 beta, IL-6, IL-8, and TNF-alpha were significantly higher in H pylori positive than in H pylori negative patients. Furthermore, the mucosal levels of IL-1 beta and IL-8 were significantly higher in specimens infected with cagA positive strains than in those infected with cagA negative strains. In H pylori positive patients, the mucosal level of IL-8 was closely correlated with that of IL-1 beta (p < 0.0001), and the mucosal level of IL-6 was closely correlated with that of TNF-alpha (p < 0.0001).

CONCLUSION

These findings suggest that the ability to induce cytokines differs among the strains; cagA+ strains induce various kinds of cytokines and may cause severe inflammation, whereas cagA- strains induce IL-8 and IL-1 beta only weakly and may cause only mild inflammation. However, as most patients infected with the cagA+ strains have gastritis, these strains may not be equivalent to ulcerogenic strains.

An 11-year-old girl with reflex sympathetic dystrophy successfully treated by thoracoscopic sympathectomy

We report on an 11-year-old girl with reflex sympathetic dystrophy (RSD) complaining of severe pain in her right upper extremity. Oral administration of narcotics or non-steroid anti-inflammatory drugs gave no relief in pain. Thoracoscopic electrocauterization of the thoracic sympathetic ganglion at the level of T3 was performed 3 months after the start of symptoms, and brought complete resolution of pain.

Cytokine expression in the alkali-burned cornea

PURPOSE

This study investigated the cytokine expression profile in alkali-burned mouse corneas, in order to elucidate the mechanisms of corneal damage and repair.

METHODS

The cytokines expressed in alkali-burned corneas were identified by polymerase chain reaction (RT-PCR), then quantitated using ELISA. Based on the ELISA results, immunohistochemical analyses were performed to localize cytokine expression.

RESULTS

Among the ten cytokines examined, IL-1 (IL-1 beta), IL-6, IL-10 and TNF-alpha mRNA were expressed in alkali-burned corneas. Quantitation revealed that IL-alpha and IL-6 were strongly induced in the early stages of alkali burn, peak production of IL-1 alpha (53.2 pg/cornea) and IL-6 (23.6 pg/cornea) occurring at days 3 and 7, respectively. The production of IL-10 and TNF-alpha was not significantly elevated during the 42 day period after burn. Immunohistochemical analyses revealed that both IL-1 alpha and IL-6 were mainly localized in regenerating epithelial basal cells.

CONCLUSIONS

IL-1 alpha and IL-6 levels in the cornea are dramatically elevated in the regenerated epithelium during the early stages of alkali burn, and may play an important role in associated corneal damage and repair.

Influence of the sensory retina on healing of the rabbit retinal pigment epithelium

PURPOSE

To compare the healing process of the retinal pigment epithelium (RPE) with and without the overlying sensory retina.

METHODS

A dome-shaped retinal detachment was created in the pigmented rabbit eye by injecting balanced salt solution into the subretinal space. The detached retina was partially removed with a vitrector; in some eyes, the detached retina was removed completely. RPE about 1.5 mm in diameter was removed from Bruch's membrane and aspirated through the retinal break. All eyes were examined morphologically.

RESULTS

Independent of the sensory retina, 4 days postoperatively the RPE wound was covered by immature RPE cells that gradually formed an epithelial-like sheet by 2 weeks postoperatively. In eyes with overlying sensory retina, regenerated RPE cells similar to normal RPE cells formed a monolayer in most areas. The RPE-photoreceptor outer segment interface gradually organized. In eyes with no sensory retina, the regenerated RPE cells were longer, mounded, and their microvilli were shorter and disorganized. The RPE cells were multilayered in some areas and often had a tubuloacinar structure.

CONCLUSIONS

The RPE wounds healed rapidly, independent of the presence of the overlying sensory retina, up to 2 weeks after RPE removal. Reconstruction of the RPE monolayer and the apical morphology of regenerated RPE cells were influenced by the sensory retina.

Determination of interferon-alpha2 allele composition in the genomic DNA from healthy volunteers and leukemic patients in Japan

The three interferon-alpha2 (IFN-alpha2) sequences identified to date differ from each other in just two nucleotide positions, both of which result in changes in amino acids. Thus, the mature IFN-alpha2a protein product is characterized by a lysine residue at position 23 (AAA) and a histidine at position 34 (CAA), IFN-alpha2b has an arginine at position 23 (AGA) and histidine at position 34 (CAT), and IFN-alpha2c has arginine residues at both positions 23 (AGA) and 34 (CGT). These nucleotide variations in the DNA sequence can be distinguished by selective restriction enzyme analysis. We studied the distributions of the three IFN-alpha2 variants by analyzing chromosomal DNA from 103 Japanese volunteers and 33 patients with hematologic disorders. Fragments of 238 bp and 617 bp of the IFN-alpha2 gene containing codons 23 and 34 were amplified by PCR using specific primers, and the PCR products were analyzed with specific restriction nucleases to identify the IFN-alpha2 variant sequences. Only IFN-alpha2b gene was detected in normal volunteers, and no IFN-alpha2a gene was detected in Japanese subjects. However, IFN-alpha2c was detected in 4 of 33 (12.1%) patients with leukemia.

Radical radiotherapy for medically inoperable non-small cell lung cancer in clinical stage I: a retrospective analysis of 149 patients

PURPOSE

In order to obtain the standard treatment results of medically inoperable non-small cell lung cancer (NSCLC) in Stage I in the post-CT scan era, a retrospective analysis of patients who were treated by radical radiotherapy was performed.

METHODS AND MATERIALS

149 cases treated between 1980 and 1989 were accumulated from ten large hospitals in Japan. All patients received a total dose of 55-75 Gy (mean 64.7 Gy) with conventional fractionation. For evaluation of treatment results, complete response (CR) rate, median survival period and long-termed survival rates were used.

RESULTS

The median survival of the all cases was 27.2 months and the actuarial 3- and 5-year survival rates were 34.2% and 22.2%, respectively. CR was obtained in 57 cases (38%). The CR rate was strongly correlated with the long-term survival (5-year survival rate in CR group: 35.1% compared with PR + NC group: 14.1% (P < 0.0001)). The size of tumor was also of prognostic importance. In 116 patients who died within 5 years after treatment, 66 patients (57%) died of local tumor regrowth.

CONCLUSION

Although the medically inoperable NSCLC patients in Stage I should be offered curative radiation therapy, development of some new steps to increase the CR rate and local control rate is urgently needed.

Expression of 47 kDa heat shock protein (HSP47) during development of mouse cornea

The 47-kDa heat shock protein (HSP47) is assumed to be a molecular chaperone specific to collagen. We examined and compared the expression patterns of HSP47 and alpha 1(I) collagen in the developing mouse cornea. Expression of HSP47 and alpha 1(I) collagen mRNAs was assessed by Northern blot analysis and in situ hybridization, and that of HSP47 protein was determined by Western immunoblotting and immunohistochemistry. HSP47 mRNA and protein were expressed strongly in early embryonic ocular tissues and were developmentally down-regulated during ocular development. Both were distributed in the mesenchymal cells (presumptive corneal stroma, sclera and choroid) and hyaloid blood vessels until post-natal day 14. The level of alpha 1(I) collagen mRNA increased during ocular development, was maximally expressed in the three days after birth, and was detected in mesenchymal cells. HSP47 expression is regulated developmentally toward completion and plays an important role during ocular development especially in corneal morphogenesis. We discuss here the relation between expression of HSP47 and alpha 1(I) collagen.

Staphylococcal enterotoxin B-specific adhesion of murine splenic T cells to a human endothelial cell line

The presence of a putative autoantigen of autoimmune disorder in a target organ may cause accumulation of specific T cells in the inflammatory region. One of the mechanisms of such accumulation involves the migration of specific-circulating T cells through the endothelial cells into the target lesion. The presence of only a few specific T cells responsive to a putative autoantigen has hampered the investigation of specific migration of circulating T cells to the target organ. We used a superantigen to investigate specific T-cell adhesion to endothelial cells, because it stimulates a large proportion of T cells with particular V beta elements and adhesion of T cells to the endothelium is a vital step in the migration process. Adhesion of murine T cells to the human endothelial cell line, EA.hy926, was specifically increased in the presence of staphylococcal enterotoxin B (SEB). The increase was interferon-gamma (IFN-gamma)-dependent, and consisted mainly of CD4+ T cells. V beta 8.1,2+ T cells preferentially adhered to endothelial cells in the presence of SEB compared with V beta 6+ T cells. Pretreatment of endothelial cells with SEB increased the adherence of V beta 8.1,2+ T cells, while anti-human leucocyte antigen (HLA)-DR and -DQ antibodies inhibited the increased adherence of V beta 8.1,2+ T cells. Our results demonstrate that increased T-cell adhesion to endothelial cells is SEB specific, and that the specificity is dependent on major histocompatibility complex (MHC) class II molecules expressed on endothelial cells and on the recognition of the SEB-MHC class II complex by V beta 8.1,2+ T cells.

MR imaging of the parotid gland in Sjögren's syndrome: a proposal for new diagnostic criteria

OBJECTIVE

Because classic diagnostic techniques for sjögren's syndrome (SS) are invasive and require radiation exposure, a noninvasive diagnostic method might benefit patients with SS. The purpose of this study was to determine whether quantitative analysis of MR images of the parotid gland can differentiate patients with SS from normal subjects.

SUBJECTS AND METHODS

We performed quantitative analysis of MR images of the parotid gland for 40 patients with definite and probable SS, for 30 normal subjects matched by age and sex to the SS patients, and for 10 patients with parotid inflammation. MR images of teh parotid gland were assessed by calculating standard deviations (SD) of signal intensity.

RESULTS

SD of signal intensity exclusively (p < .0001) separated MR images of the parotid glands of patients with definite SS from those of normal subjects. SD of signal intensity for the parotid glands of patients with probable SS also were significantly higher (p < .001) than those of normal subjects. Changes in signal intensity were specific for SS and did not occur with parotid inflammation. Tentative categorization on the basis of signal intensity patterns on MR images of the parotid glands of SS patients showed a high correlation with the results of labial gland biopsy (r = .834) and sialography (r = .936).

CONCLUSION

Taken together, these results conclusively indicate that quantitative analysis of MR images for SD of signal intensity is useful method for diagnosing SS and can replace classic methods, which are invasive.

Helicobacter pylori cagA gene and expression of cytokine messenger RNA in gastric mucosa

BACKGROUND & AIMS

Helicobacter pylori strains possessing the cagA gene are thought to be associated with gastroduodenal diseases. Furthermore, some cytokines are considered to play a role in gastric mucosal inflammation. The aim of this study was to investigate the relationship between cagA gene and cytokine messenger RNA (mRNA) expression in gastric mucosa.

METHODS

In 160 patients, the cagA gene was detected using polymerase chain reaction, and interleukin (IL) 1 beta, IL-6, IL-7, IL-8, IL-10, and tumor necrosis factor (TNF) alpha mRNA were detected using reverse-transcription polymerase chain reaction.

RESULTS

Specimens infected with cagA gene-positive strains (cagA-positive specimens) had significantly more severe infiltration of polymorphonuclear leukocytes and mononuclear cells than those infected with cagA gene-negative strains (cagA-negative specimens). Levels of expression of IL-6, IL-7, IL-8, IL-10, and TNF-alpha mRNA were significantly higher in H. pylori-positive than H. pylori-negative patients. Furthermore, the level of IL-8 mRNA expression was significantly higher in cagA-positive than cagA-negative specimens.

CONCLUSIONS

cagA-positive strains induce the expression of IL-8 mRNA, suggesting that IL-8 may play important roles in the pathogenesis of gastroduodenal diseases associated with H. pylori infection.

[Untoward effects of low dose methotrexate therapy in rheumatoid arthritis]

Sixty patients with rheumatoid arthritis who were administered weekly low dose methotrexate (MTX) were retrospectively analyzed for their untoward effects of MTX by interviewing to the patients and by the medical records. Cough and sputa were the most frequent symptoms (23.3%) and gastrointestinal symptoms were the next (20%). Five of 60 patients (8.2%) showed liver function test abnormalities, and four (6.7%) exhibited transient exacerbation of arthralgia for several hours to a few days after MTX administration. Three patients (5%) suffered from interstitial pneumonitis. Hair loss was seen in 3 patients (5%), and headache, leucocytepenia, fever, skin eruption, abnormal taste, hemorrhagic cystitis, and flashing were experienced in a patient, respectively. Three (5%) suffered from fungal infection, and herpes zoster, sepsis, and osteomyelitis were experienced in each one patient, respectively. MTX was withdrawn in three patients (5%) because of cough and sputa the drug was withdrawn in other three patients because of the interstitial pneumonia, and was drawn in another three patients because of transient exacerbation of arthralgia. The drug was withdrawn in each one patient, because of nausea and vomiting, skin eruption, osteomyelitis, and sepsis, respectively. Overall, MTX were withdrawn in 21 patients (35%), and, of those, 13 patients (21.7%) because of untoward effects and 8 patients (13.3%) because of the lack of efficacy.

MR imaging of liver cirrhosis

PURPOSE

The objective of this study was to identify the factors affecting the visualization of regenerating nodules in cirrhotic liver by MR imaging.

MATERIAL AND METHODS

MR images from patients with liver cirrhosis and normal subjects were studied, and signal intensity within the liver was measured and correlated with histologic findings. A reference phantom was also used as a standard.

RESULTS

The signal intensity of the liver on T2-weighted (T2WI) spin-echo (SE) images was significantly increased in patients with liver cirrhosis. Multiple ring-like or reticular high-intensity areas (RHAs) were demonstrated on T2WI SE images in 44 of 125 cirrhotic livers. Histologic examination in 44 cases revealed various degrees of inflammatory changes in fibrous septa surrounding regenerative nodules in all specimens, vascular dilation in fibrous septa in 4 specimens, and no hemosiderin deposition in some specimens. The results of linear discriminant analysis showed that inflammatory changes in fibrous septa were significantly more pronounced in cases with RHAs on MR.

CONCLUSION

RHAs seen on T2WI SE images may correspond to fibrous septa with inflammation. The signal intensity of fibrous septa surrounding regenerative nodules on T2WI SE images may be increased in liver cirrhosis due to inflammation or vascular dilation, contributing to the visualization of regenerating nodules as relatively low-intensity regions on MR.