Diaquabis(propane-1,2-diamine-N,N')nickel(II) bis(p-toluenesulfonate)

The crystal structure of the title compound, [Ni(C(3)H(10)N(2))(2)(H(2)O)(2)](C(7)H(7)O(3)S)(2) or [Ni(H(2)O)(2)[NH(2)CH(2)CH(NH(2))CH(3)](2)](CH(3)C(6)H(4)SO(3))(2), exhibits a layered structure in which the complex cations and the p-toluenesulfonate anions form alternating layers. The central Ni(II) atom of the cation resides on a crystallographic inversion centre and has a slightly distorted octahedral coordination composed of the water ligands bonding through oxygen in a trans arrangement and the N,N'-bidentate propanediamine ligands. The p-toluenesulfonate anions are arranged with the sulfonate groups turned alternately towards opposite sides of the layers. The structure of the layers is stabilized by a network of hydrogen bonds between the sulfonate O atoms, water molecules and the propanediamine N atoms.

Gene structure of the human DDX3 and chromosome mapping of its related sequences

The human DDX3 gene (GenBank accession No. U50553) is the human homologue of the mouse Ddx3 gene and is a member of the gene family that contains DEAD motifs. Previously, we mapped the gene to the Xp11.3-11.23. In this report, we describe the structural organization of the human DDX3 gene. It consisted of 17 exons that span approximately 16 kb. An Alu element was present in the intron 13. Its organization was the same as that of the human DBY gene, a closely related sequence present on the Y chromosome. We also identified two processed pseudogenes (DDX3) with a sequence that is highly homologous to those of DDX3 cDNAs, but contain a translation termination codon within its open-reading frame. Pseudogenes are mapped on human chromosomes 4 and X, respectively. In this paper, we discuss the relationships between DDX3 and its related sequences that have been isolated.

Isolation and characterization of a Bacillus thuringiensis ssp. kurstaki strain toxic to Spodoptera exigua and Culex pipiens

A strain of Bacillus thuringiensis with dual toxicity was isolated from Korean soil samples and named K2. K2 was determined as ssp. kurstaki (H3a3b3c) by serological test and produced bipyramidal-shaped parasporal inclusions. The plasmid and protein profiles of B. thuringiensis K2 were different from those of the reference strain, ssp. kurstaki HD-1. To verify gene type of B. thuringiensis K2, PCR analysis with specific cry gene primers was performed. The result showed that B. thuringiensis K2 had cry1Aa, cry1Ab, cry1C, and cry1D type genes, whereas ssp. kurstaki HD-1 had cry1Aa, cry1Ab, cry1Ac, and cry2 type genes. In addition, B. thuringiensis K2 had high toxicity against Spodoptera exigua and Culex pipiens, whereas B. thuringiensis ssp. kurstaki HD-1 does not have high toxicity against these two insect species.

Gene amplification and expression of the DNA repair enzyme, N-methylpurine-DNA glycosylase (MPG) in HPV-infected cervical neoplasias

BACKGROUND

Lethal and mutagenic damages of DNA is caused by a variety of agents including viruses. It is known that HPV is one of the major causes of cervical carcinogenesis and that cells eliminate DNA lesions with DNA repair enzymes. However, the role of N-methylpurine-DNA glycosylase (MPG) is not known in the development of cervical cancer.

MATERIALS AND METHODS

Multiplex polymerase chain reaction (PCR) was used for the detection and typing of HPV in the biopsy. Gene amplification of MPG was measured by a PCR-based assay. The mRNA levels of MPG were determined by reverse transcription-PCR using hypoxanthine-guanine phosphoribosyl transferase as the reference gene. An immunohistochemical technique was used to examine the distribution of MPG in the tissues.

RESULTS

Of 68 Korean cervical neoplasia patients, 86.8% showed HPV infection. High-risk HPV 16/18 were the most prevalent but positive only in 47.3% of the invasive cancer patients. Gene amplification of MPG was significantly increased in high-risk HPV-infected tissues as compared to low-risk HPV-infected and normal tissues (p < 0.05). The mRNA levels of MPG were higher in HPV-infected invasive carcinoma than normal cervical tissues. Immunohistochemical staining revealed that the intracellular expression and distribution (localization) of MPG altered in the cervical neoplasia. Interestingly, MPG expression in CIN III and invasive carcinoma (IC) was much higher than normal and CIN I. Granular positivity of MPG was notable in the perinuclear regions of the cytoplasm in HPV-infected invasive cancer.

CONCLUSION

This is the first report on MPG expression in cervical neoplasia. Our results indicate that the gene amplification and expression of MPG were increased in high-risk HPV-infected cervical neoplasias and the intracellular distribution of MPG protein was altered, suggesting a role of MPG in carcinogenesis.

A sequence-ready map for human chromosome 12q15-21

Construction of sequence-ready clone map is an essential step toward sequencing the human genome. We chose a region that is frequently amplified in liposarcoma between D12S350 and D12S106 in chromosome 12q15-21 to build a PAC/BAC clone contig map. This region was spanned by 4 YACs and contained 30 STS on the YAC and radiation hybrid (RH) framework maps, providing an average STS spacing of 160 kb if each YAC is approximately 1.2 Mb in size. To convert a STS-based YAC map to a STS-based contig map of bacterial clones, 22 non-polymorphic STS markers were used as probes to screen the high density gridded arrays of PAC and BAC clones by filter hybridizations, followed by assembly of clones into contigs by marker content. Contigs have been extended and joined by direct end sequencing of appropriate clones, generating new STSs and rescreening the library as necessary. Using these approaches, we have constructed 5 contigs covering the region with the largest single contig being 1.4 Mb and a final size estimation of 3.6 Mb. The map is comprised of 17 YACs, 187 PACs, 160 BACs, and 17 cosmids; onto this, 6 polymorphic, 97 non-polymorphic, 24 ESTs, and 4 gene-based markers are now placed in a unique order, providing an average resolution of approximately 28 kb. Of a total of 131 markers, 97 were developed in the present study. The sequence-ready map should provide a framework to generate complete DNA sequence and ultimately gene map of this segment of chromosome 12.

Neuropathic arthropathy of the elbow. A report of five cases

BACKGROUND

Neuropathic arthropathy of the elbow is rare and characterized by a painless but unstable articulation. The functional capacity of patients with this condition has not been reviewed in detail.

METHODS

Five male patients, with an average age of fifty-one years, were treated for neuropathic arthropathy of the elbow. The underlying conditions associated with the arthropathy included syringomyelia, insulin-dependent diabetes mellitus, end-stage renal failure, and two cases of polyneuropathy of unknown cause. Four patients sought medical attention after a specific traumatic event. Peripheral sensory and motor dysfunction was present in each patient. Radiographs of the elbow revealed dislocation, fracture fragmentation, and heterotopic ossification. Our management of the neuropathic elbows centered on maintenance of a functional arc of motion through physical therapy aimed at regaining muscle strength and the use of orthoses for support. Operative treatment was performed for an associated ulnar or radial nerve compression syndrome in three patients, and an open reduction and internal fixation of an unstable proximal ulnar nonunion associated with loose implants was performed in one.

RESULTS

The patients were followed for an average of nineteen months, with a range of twelve to thirty-six months. All patients had a pain-free elbow with a functional range of motion at the most recent follow-up examination, and none wished to have further treatment. The operatively treated ulnar nonunion united successfully. All three patients treated surgically for an associated nerve compression syndrome had recovery of nerve function.

CONCLUSION

In the face of instability and gross distortion of the joint, the patients in this series demonstrated remarkably good function.

Displacement of microcalcifications during stereotactic 11-gauge directional vacuum-assisted biopsy with marking clip placement: case report

A 53-year-old woman with right breast microcalcifications of intermediate concern underwent stereotactic directional vacuum-assisted biopsy with marking clip placement. Postbiopsy mammograms showed displacement of a few of the targeted microcalcifications adjacent to misplaced marker clips. Mammography following stereotactic breast biopsy is important to document the location and number of residual calcifications and to determine the adequacy and location of clip placement.

Ischemic bile duct injury as a serious complication after transarterial chemoembolization in patients with hepatocellular carcinoma

BACKGROUND

Bile duct injuries after transarterial chemoembolization (TACE) have been reported; however, the exact pathogenic mechanisms and clinical implications of the injuries remain to be clarified.

STUDY

A total of 950 consecutive patients with hepatocellular carcinoma (HCC) were studied. Among them, 807 were treated with TACE and the remaining 143 were treated with transarterial chemoinfusion (TACI) of cisplatin.

RESULTS

None of 143 patients with HCC treated with TACI were found to have any radiographic evidence of biliary injury. In contrast, of the 807 patients treated with TACE, 17 (2%) developed biliary complications. Of all complications, 12 (71%) were subcapsular bilomas; 3 (17%), focal strictures of the common hepatic duct or common bile duct; and 2 (12%), diffuse mild dilatation of the intrahepatic bile ducts. Interestingly, 2 of the 12 bilomas were found in the lobe that was not embolized with gelatin sponge particles. The median numbers of TACE tended to be greater in the patients with focal stricture than in those with bilomas (6.0 vs. 2.5; p = 0.08). All 3 patients with focal strictures and 4 of the 12 patients with bilomas had associated serious bacterial infections at presentation.

CONCLUSIONS

Bilomas seem to be caused by iodized oil rather than gelatin sponge particles; focal strictures of large bile ducts seem to be caused by gelatin sponge particles. We suggest that adjustments in the amounts of iodized oil or gelatin sponge particles and in the sites of embolization may reduce ischemic biliary injuries after TACE.

Characterization of publicly available SNPs in the Korean population

Single-nucleotide polymorphisms (SNPs) are the most abundant form of genetic variations and have a great potential for mapping studies of complex genetic traits. Currently a great deal of effort is invested in the identification of SNPs, and a large volume of data is already available through public databases (NCBI, NCI, WICGR, HGBASE). For an association mapping study, SNP allele frequencies in the population are critical. As an initial step toward construction of an SNP database of the Korean population, we have determined the allele frequencies of 300 cSNPs selected from the public database in 24 individuals. Among the tested markers, approximately 23% did not show polymorphism in the population. The results suggest that the ethnic and population based differences should be considered in the selection of SNPs for the study of complex diseases with association mapping methods.

Effect of heavy metals (Cu, Pb, and Ni) on the compositions of EPS in biofilms

A series of batch adsorption tests to estimate the biofilm capacity for removal of the heavy metals (Cu, Pb, and Ni) in wastewater were carried out. The metal sorption results were fitted to the Freundlich isotherm model to compare their sorption capacity. The change of the composition of EPSs (extracellular polymeric substances) was simultaneously represented by the ratio of carbohydrate to protein (C/P) when the biofilm was exposed to the heavy metals. EPS composed of slime loosely bound to the cell and capsular materials was extracted by the four general extraction methods including regular centrifugation, regular centrifugation with formaldehyde, EDTA extraction and steam extraction. Although the various extraction methods showed different results, C/P ratio of biofilm exposed to copper and lead metal ions was generally lower than that of control.

The application of an anti-angiogenic gene (thrombospondin-1) in the treatment of human prostate cancer xenografts

Angiogenesis is a critical event for solid tumor growth and metastasis. Within a given microenvironment, the angiogenic response is determined in part by the balance between angiogenesis inducers and inhibitors. The aim of this study was to establish a thrombospondin-1 (TSP-1) ( an antiangiogenic gene) expression vector, and to determine the feasibility for use of TSP-1 in prostate cancer gene therapy. The results of this study showed that pCR-TSP-1, the cloned TSP-1 expression plasmid vector, expressed the TSP-1 gene efficiently in DU145, a human prostate cancer cell line. pCR -TSP-1 did not exert any significant growth inhibitory activity on the tested cell line in vitro. However, TSP-1 overexpression inhibited the growth of DU-145 xenografts in Balb/c nude mice when directly transfected with pCR-TSP-1 in combination with a liposomal agent (DOSPER). Histological analysis showed that there were extensive areas of necrosis in the TSP-1 overexpressing tumors, whereas no necrotic foci were observed in the control tumors. Furthermore, the microvessel density was lower in the TSP-1 overexpressing tumors compared to the control tumors. These results suggest that TSP-1 may be a potentially useful gene for prostate cancer gene therapy.

Biochemical responses of fish exposed to a harmful dinoflagellate Cochlodinium polykrikoides

To elucidate the ichthyotoxic mechanisms of a harmful dinoflagellate Cochlodinium polykrikoides, biochemical responses of fish exposed to blooms were investigated. Particularly, based on our finding that oxidative damages of gill were associated with fish mortality (J. Plankton Res. 21 (1999) 2105-2115), dysfunction of ion-transporting enzymes and secretion of gill mucus of fish exposed to this bloom species were examined. The susceptibilities of several fishes to C. polykrikoides were different; the active pelagic fishes such as black scraper Thamnaconus septentrionalis, red sea bream Pagrus major, beakperch Oplegnathus fasciatus and seaperch Malakichthys wakiyae, were more vulnerable than the benthic fishes, flounder Paralichthys olivaceus and rockfish Sebastes inermis. In addition, the higher the algal cell density, the higher the fish mortality. When the test fishes were exposed to C. polykrikoides of 5000 cells ml(-1), the transport-related enzymes, carbonic anhydrase and Na(+)/K(+)-ATPase activities were significantly decreased. The activity of carbonic anhydrase was decreased with increasing algal cell density and exposure time. The quantity of total polysaccharide in gill mucus is higher in the fish exposed to C. polykrikoides than in the control fish; the magnitudes were higher in the pelagic fishes than that of benthic fishes. Moreover, a drop of blood pH and oxygen partial pressure (pO(2)) was also observed in red sea bream and flounder subjected to C. polykrikoides. These results suggest that the inactivation of gill transport-related enzymes activities, the fall in blood pO(2) and abnormal secretion of gill mucus by the C. polykrikoides may be one of the principal causes of fish kill.

Subcellular localization of presenilins during mouse preimplantation development

The genes defective in familial Alzheimer's disease encode the proteins presenilin 1 and 2 (PS1 and 2). Expression of presenilins (PSs) and their proteolytic processing are regulated during neuronal development. Even though these proteins are detected and regulated mainly in Golgi and endoplasmic reticulum, their subcellular distribution during the development is not known. The present study aimed to investigate the localization of PSs and their role during early developmental stage using mouse embryo model. At preimplantation stage, PSs were detected not only in cytoplasm, but also in the nucleus from oocyte to 2.5 dpc (day postcoitum), then disappeared in the nucleus at blastocyst stage (3.5 dpc). Antisense against PS1 and PS2 decreased the transition to blastocyst stage, whereas each antisense alone had no effect. Treatment with lactacystin (26S proteosome inhibitor), which arrest cell cycle at M phase, redistributed PSs into centrosome-kinetochore microtubule. PS2 overexpression in HEK 293 cell arrested cell cycle at S phase. These data suggest that PSs play key roles in cell division and differentiation during early development.

One hundred and eleven liver resections for hilar bile duct cancer

A positive correlation between absence of residual tumor at resection margins and long-term survival in the treatment of hilar bile duct carcinoma has encouraged some surgeons to use a more radical approach, including liver/portal vein resection and combined pancreatoduodenectomy. However, if liver resection is associated with significant morbidity and mortality, it may not produce any overall benefit. This review was undertaken in an attempt to determine whether liver resection is a safe procedure and whether if has any beneficial effect over that of local bile duct excision alone, in terms of achieving curative resection and long-term survival. The records of 151 patients with hilar bile duct carcinoma surgically treated between June 1989 and December 1997 at the Asan Medical Center, Seoul, were retrospectively analyzed. Surgical resection was possible in 128 patients. The remaining 23 patients had surgical palliative drainage. Local bile duct excision alone was performed in 17 patients. Liver resection for tumor extending to secondary bile ducts or hepatic parenchyma was performed in 111 patients; portal vein resection was necessary in 29 of these 111 patients (26.1%) and pancreatoduodenectomy was combined in 18 patients (16.2%). Seven patients died during hospitalization after liver resection, an operative mortality of 6.3%. Margins of bile duct resection were free of tumor on histologic examination in 4 of the 17 local bile duct excisions, but in 86 of the 111 liver resections. The cumulative survival rate after local bile duct excision was 85.7% at 1 year, 42.9% at 2 years, 21.4% at 3 years, and 0% at 4 years. However, the survival rate after liver resection (excluding operative mortality) was 97.1% at 1 year, 72.8% at 2 years, 55.3% at 3 years, and 24.0% at 5 years. Survival and the percentage of patients with tumor-free resection margins after liver resection were superior to those after local bile duct excision. Resection of hilar bile duct carcinoma offers long-term survival only when surgery is aggressive and includes liver resection.

One hundred and eleven liver resections for hilar bile duct cancer

A positive correlation between absence of residual tumor at resection margins and long-term survival in the treatment of hilar bile duct carcinoma has encouraged some surgeons to use a more radical approach, including liver/portal vein resection and combined pancreatoduodenectomy. However, if liver resection is associated with significant morbidity and mortality, it may not produce any overall benefit. This review was undertaken in an attempt to determine whether liver resection is a safe procedure and whether if has any beneficial effect over that of local bile duct excision alone, in terms of achieving curative resection and long-term survival. The records of 151 patients with hilar bile duct carcinoma surgically treated between June 1989 and December 1997 at the Asan Medical Center, Seoul, were retrospectively analyzed. Surgical resection was possible in 128 patients. The remaining 23 patients had surgical palliative drainage. Local bile duct excision alone was performed in 17 patients. Liver resection for tumor extending to secondary bile ducts or hepatic parenchyma was performed in 111 patients; portal vein resection was necessary in 29 of these 111 patients (26.1%) and pancreatoduodenectomy was combined in 18 patients (16.2%). Seven patients died during hospitalization after liver resection, an operative mortality of 6.3%. Margins of bile duct resection were free of tumor on histologic examination in 4 of the 17 local bile duct excisions, but in 86 of the 111 liver resections. The cumulative survival rate after local bile duct excision was 85.7% at 1 year, 42.9% at 2 years, 21.4% at 3 years, and 0% at 4 years. However, the survival rate after liver resection (excluding operative mortality) was 97.1% at 1 year, 72.8% at 2 years, 55.3% at 3 years, and 24.0% at 5 years. Survival and the percentage of patients with tumor-free resection margins after liver resection were superior to those after local bile duct excision. Resection of hilar bile duct carcinoma offers long-term survival only when surgery is aggressive and includes liver resection.

Enhancement of adenoviral transduction with polycationic liposomes in vivo

Although the high transfection efficiency with adenovirus in vitro is well documented, it is still not clear whether adenoviral vectors are effective in vivo in solid tumor models. In our preliminary experiment, transduction of tumor tissue was limited to just around the injection site after intratumoral injection of the adenoviral vector. To improve the transduction efficiency in vivo, we tried a combination of adenoviral vector and liposome in our animal model. Adenovirus carrying human placental alkaline phosphatase (AdALP) and Lipofectamine or 1,3-di-oleoyloxy-2-(6-carboxyspermyl)-propylamide were used as a marker gene and the cationic liposome, respectively. A >15-fold increase in the transfection efficiency was observed in CT26 tumor cell lines with the combination of AdALP adenovirus carrying murine granulocyte-macrophage colony-stimulating factor (AdmGM-CSF), and liposome compared with adenovirus alone, showing the feasibility of the combination treatment. In the animal model, with the combination of liposome and AdALP, deeper and wider distribution of the marker gene in the tumor mass was shown. We conclude that the limitations of direct application of adenoviral vectors in a solid tumor model could be overcome by the use of cationic liposomes. This approach will facilitate the more effective delivery of adenoviral vectors in a clinical trial setting.

Expression of transforming growth factor-alpha mRNA in livers of patients with chronic viral hepatitis and hepatocellular carcinoma

BACKGROUND

Transforming growth factor-alpha (TGFalpha) is an important autocrine growth factor of hepatocytes. The authors evaluated the roles of TGFalpha in chronic viral hepatitis (CVH) and hepatocellular carcinoma (HCC).

METHODS

The authors measured the amounts of TGFalpha mRNA in liver tissues from 18 patients with HCC, 31 patients with CVH, and 7 normal controls. " Hot-start" reverse transcription-polymerase chain reaction (RT-PCR) using oligo-dT and specific primers detected TGFalpha mRNA in total cellular RNA extracted from liver tissues. The levels of TGFalpha mRNA were determined by the end point titers of serial, two-fold dilutions of cDNA. The amounts of hepatitis B virus RNA (HBV-RNA) in livers of patients with chronic hepatitis B also were measured by Northern blot hybridization.

RESULTS

TGFalpha mRNA levels were extremely higher in patients with HCC compared with patients with CVH and normal controls, and the levels in patients with CVH also were elevated compared with normal controls. The levels of TGFalpha mRNA were overexpressed in the underlying livers of patients with HCC compared with patients with CVH, although they were lower than those found in HCC tissues. The levels of TGFalpha mRNA were higher in samples from patients with chronic hepatitis B than in samples from patients with chronic hepatitis C. The levels of TGFalpha mRNA were not correlated with serum alanine aminotransferase or HBV-RNA levels in liver tissues in patients with chronic hepatitis B. However, the expression of TGFalpha mRNA tended to be higher in the livers of patients with raised serum alpha-fetoprotein levels.

CONCLUSIONS

The overexpression of TGFalpha mRNA in the liver seems to be associated with the regeneration of hepatocytes rather than hepatic necrosis or viral replication. Also, it may be related closely to the development or progression of HCC, especially in the livers of patients with chronic hepatitis B.

Interaction of human Ku70 with TRF2

Ku, a heterodimer of 70- and 80-kDa subunits, plays a general role in the metabolism of DNA ends in eukaryotic cells, including double-strand DNA break repair, V(D)J recombination, and maintenance of telomeres. We have utilized the yeast two-hybrid system to identify Ku70-interacting proteins other than Ku80. Two reactive clones were found to encode the dimerization domain of TRF2, a mammalian telomeric protein that binds to duplex TTAGGG repeats at chromosome ends. This interaction was confirmed using bacterial fusion proteins and co-immunoprecipitations from eukaryotic cells overexpressing TRF2. The transfected TFR2 colocalized with Ku70.

Expression of transforming growth factor-alpha mRNA in livers of patients with chronic viral hepatitis and hepatocellular carcinoma

BACKGROUND

Transforming growth factor-alpha (TGFalpha) is an important autocrine growth factor of hepatocytes. The authors evaluated the roles of TGFalpha in chronic viral hepatitis (CVH) and hepatocellular carcinoma (HCC).

METHODS

The authors measured the amounts of TGFalpha mRNA in liver tissues from 18 patients with HCC, 31 patients with CVH, and 7 normal controls. " Hot-start" reverse transcription-polymerase chain reaction (RT-PCR) using oligo-dT and specific primers detected TGFalpha mRNA in total cellular RNA extracted from liver tissues. The levels of TGFalpha mRNA were determined by the end point titers of serial, two-fold dilutions of cDNA. The amounts of hepatitis B virus RNA (HBV-RNA) in livers of patients with chronic hepatitis B also were measured by Northern blot hybridization.

RESULTS

TGFalpha mRNA levels were extremely higher in patients with HCC compared with patients with CVH and normal controls, and the levels in patients with CVH also were elevated compared with normal controls. The levels of TGFalpha mRNA were overexpressed in the underlying livers of patients with HCC compared with patients with CVH, although they were lower than those found in HCC tissues. The levels of TGFalpha mRNA were higher in samples from patients with chronic hepatitis B than in samples from patients with chronic hepatitis C. The levels of TGFalpha mRNA were not correlated with serum alanine aminotransferase or HBV-RNA levels in liver tissues in patients with chronic hepatitis B. However, the expression of TGFalpha mRNA tended to be higher in the livers of patients with raised serum alpha-fetoprotein levels.

CONCLUSIONS

The overexpression of TGFalpha mRNA in the liver seems to be associated with the regeneration of hepatocytes rather than hepatic necrosis or viral replication. Also, it may be related closely to the development or progression of HCC, especially in the livers of patients with chronic hepatitis B.

Results of photodynamic therapy for ablation of dysplasia and early cancer in Barrett's esophagus and effect of oral steroids on stricture formation

OBJECTIVE

The primary goal of this study was to investigate whether oral steroids would reduce the incidence of stricture formation after photodynamic therapy (PDT) in Barrett's patients. The effect of balloon window length, pretreatment of nodules, retreatment of skipped areas, and subsequent PDT on the incidence of strictures was also investigated. The ultimate goal of treatment was elimination of dysplasia, early cancer, and Barrett's mucosa.

METHODS

A total of 60 patients were injected with Photofrin (2 mg/kg). Patients were randomized to receive PDT (n = 30) or PDT and oral prednisone (n = 30). Two days later, 630 nm light (KTP/dye laser) was delivered using a 5- or 7-cm windowed balloon at a light dose of 200 or 175 J/cm. The majority of patients received 200 J/cm using a 7-cm balloon. Nodules were pretreated with a short diffuser at a dose of 50-75 J/cm. Additional light was delivered to skipped areas 2-3 days later. Endoscopies were conducted every 3-6 months to evaluate the response. Residual or recurrent Barrett's was treated using neodymium:aluminum-yttrium-garnet (Nd:YAG) laser (small areas) or was retreated with PDT.

RESULTS

The effect of steroids on the incidence of strictures was analyzed in patients receiving a single treatment with a light dose of 200 J/cm using a 7- cm balloon. There was no reduction in the incidence of strictures in patients receiving PDT and steroids (29%) compared to those receiving PDT alone (16%). Treatment using a 7-cm balloon caused more strictures (31%) than treatments using a 5-cm balloon (7%). Pretreatment of nodules or retreatment of skipped areas did not increase strictures. Patients receiving subsequent PDT had a higher incidence of strictures. Cancer was eliminated in all patients. High-grade dysplasia was eliminated in 41 of 43 patients (96%). Barrett's mucosa was totally eliminated in 25 of 60 patients (42%).

CONCLUSIONS

Oral prednisone after PDT did not reduce the incidence of strictures. Subsequent PDT and longer balloon window were associated with higher incidence of strictures. PDT followed by thermal ablation of small islands eliminated dysplasia, early cancer, and Barrett's mucosa.