Activation of Holliday junction recognizing protein involved in the chromosomal stability and immortality of cancer cells

We identified a novel gene HJURP (Holliday junction-recognizing protein) whose activation seemed to play a pivotal role in the immortality of cancer cells. HJURP was considered a possible downstream target for ataxia telangiectasia mutated signaling, and its expression was increased by DNA double-strand breaks (DSB). HJURP was involved in the homologous recombination pathway in the DSB repair process through interaction with hMSH5 and NBS1, which is a part of the MRN protein complex. HJURP formed nuclear foci in cells at S phase and those subjected to DNA damage. In vitro assays implied that HJURP bound directly to the Holliday junction and rDNA arrays. Treatment of cancer cells with small interfering RNA (siRNA) against HJURP caused abnormal chromosomal fusions and led to genomic instability and senescence. In addition, HJURP overexpression was observed in a majority of lung cancers and was associated with poor prognosis as well. We suggest that HJURP is an indispensable factor for chromosomal stability in immortalized cancer cells and is a potential novel therapeutic target for the development of anticancer drugs.

Dikkopf-1 as a novel serologic and prognostic biomarker for lung and esophageal carcinomas

Gene expression profile analysis of lung and esophageal carcinomas revealed that Dikkopf-1 (DKK1) was highly transactivated in the great majority of lung cancers and esophageal squamous cell carcinomas (ESCC). Immunohistochemical staining using tumor tissue microarrays consisting of 279 archived non-small cell lung cancers (NSCLC) and 280 ESCC specimens showed that a high level of DKK1 expression was associated with poor prognosis of patients with NSCLC as well as ESCC, and multivariate analysis confirmed its independent prognostic value for NSCLC. In addition, we identified that exogenous expression of DKK1 increased the migratory activity of mammalian cells, suggesting that DKK1 may play a significant role in progression of human cancer. We established an ELISA system to measure serum levels of DKK1 and found that serum DKK1 levels were significantly higher in lung and esophageal cancer patients than in healthy controls. The proportion of the DKK1-positive cases was 126 of 180 (70.0%) NSCLC, 59 of 85 (69.4%) SCLC, and 51 of 81 (63.0%) ESCC patients, whereas only 10 of 207 (4.8%) healthy volunteers were falsely diagnosed as positive. A combined ELISA assays for both DKK1 and carcinoembryonic antigen increased sensitivity and classified 82.2% of the NSCLC patients as positive whereas only 7.7% of healthy volunteers were falsely diagnosed to be positive. The use of both DKK1 and ProGRP increased sensitivity to detect SCLCs up to 89.4%, whereas false-positive rate in healthy donors was only 6.3%. Our data imply that DKK1 should be useful as a novel diagnostic/prognostic biomarker in clinic and probably as a therapeutic target for lung and esophageal cancer.

Increases of amphiregulin and transforming growth factor-alpha in serum as predictors of poor response to gefitinib among patients with advanced non-small cell lung cancers

Serum levels of amphiregulin and transforming growth factor-alpha (TGF-alpha), which were identified previously to be expressed at high levels in non-small cell lung cancer (NSCLC) with poor response to gefitinib, were examined by ELISA using blood samples taken from 50 patients with advanced NSCLCs. Of 14 cases that revealed above the cutoff line for amphiregulin in serum, 12 responded poorly to gefitinib, whereas 18 of the 36 cases showing below the cutoff revealed partial response (PR) or stable disease (SD; P = 0.026). Thirteen of 15 patients who were positive for TGF-alpha responded poorly to gefitinib, whereas 18 of the 35 patients with negative TGF-alpha levels turned out to be relatively good responders (P = 0.014). Of 22 patients with positive values for either or both markers, 19 were poor responders. On the other hand, among 28 patients negative for both markers, 17 were classified into the PR or SD groups (P = 0.001). Gefitinib-treated NSCLC patients whose serum amphiregulin or TGF-alpha was positive showed a poorer tumor-specific survival (P = 0.037 and 0.002, respectively, by univariate analysis) compared with those whose serum amphiregulin or TGF-alpha concentrations were negative. Multivariate analysis showed an independent association between positivity for TGF-alpha and shorter survival times among NSCLC patients treated with gefitinib (P = 0.034). Amphiregulin or TGF-alpha positivity in NSCLC tissues was significantly higher in male, nonadenocarcinomas, and smokers. Our data suggest that the status of amphiregulin and TGF-alpha in serum can be an important predictor of the resistance to gefitinib among patients with advanced NSCLC.

ANLN Plays a Critical Role in Human Lung Carcinogenesis through the Activation of RHOA and by Involvement in the Phosphoinositide 3-Kinase/AKT Pathway

Gene expression profile analysis of non-small cell lung cancers (NSCLC) and subsequent functional analyses revealed that human ANLN, a homologue of anillin, an actin-binding protein in Drosophila, was transactivated in lung cancer cells and seemed to play a significant role in pulmonary carcinogenesis. Induction of small interfering RNAs against ANLN in NSCLC cells suppressed its expression and resulted in growth suppression; moreover, treatment with small interfering RNA yielded cells with larger morphology and multiple nuclei, which subsequently died. On the other hand, induction of exogenous expression of ANLN enhanced the migrating ability of mammalian cells by interacting with RHOA, a small guanosine triphosphatase, and inducing actin stress fibers. Interestingly, inhibition of phosphoinositide 3-kinase/AKT activity in NSCLC cells decreased the stability of ANLN and caused a reduction of the nuclear ANLN level. Immunohistochemical staining of nuclear ANLN on lung cancer tissue microarrays was associated with the poor survival of NSCLC patients, indicating that this molecule might serve as a prognostic indicator. Our data imply that up-regulation of ANLN is a common feature of the carcinogenetic process in lung tissue, and suggests that selective suppression of ANLN could be a promising approach for developing a new strategy to treat lung cancers.

Activation of CDCA1-KNTC2, members of centromere protein complex, involved in pulmonary carcinogenesis

We found cotransactivation of cell division associated 1 (CDCA1) and kinetochore associated 2 (KNTC2), members of the evolutionarily conserved centromere protein complex, in non-small cell lung carcinomas (NSCLC). Immunohistochemical analysis using lung cancer tissue microarray confirmed high levels of CDCA1 and KNTC2 proteins in the great majority of lung cancers of various histologic types. Their elevated expressions were associated with poorer prognosis of NSCLC patients. Knockdown of either CDCA1 or KNTC2 expression with small interfering RNA significantly suppressed growth of NSCLC cells. Furthermore, inhibition of their binding by a cell-permeable peptide carrying the CDCA1-derived 19-amino-acid peptide (11R-CDCA1(398-416)) that correspond to the binding domain to KNTC2 effectively suppressed growth of NSCLC cells. As our data imply that human CDCA1 and KNTC2 seem to fall in the category of cancer-testis antigens, and that their simultaneous up-regulation is a frequent and important feature of cell growth/survival of lung cancer, selective suppression of CDCA1 or KNTC2 activity and/or inhibition of the CDCA1-KNTC2 complex formation could be a promising therapeutic target for treatment of lung cancers.

The neuromedin U-growth hormone secretagogue receptor 1b/neurotensin receptor 1 oncogenic signaling pathway as a therapeutic target for lung cancer

Using a genome-wide cDNA microarray to search for genes that were specifically up-regulated in non-small cell lung cancers (NSCLC), we identified an abundant expression of neuromedin U (NMU) in the great majority of lung cancers. Immunohistochemical analysis showed a significant association of NMU expression with poorer prognosis of patients with NSCLC. Treatment of NSCLC cells with short interfering RNA against NMU suppressed its expression and inhibited the growth of the cells; on the other hand, the induction of exogenous expression of NMU conferred growth-promoting activity and enhanced cell mobility in vitro. We found that two G protein-coupled receptors, growth hormone secretagogue receptor 1b and neurotensin receptor 1, were also overexpressed in NSCLC cells, and that a heterodimer complex of these receptors functioned as an NMU receptor. The NMU-receptor interaction subsequently induced the generation of a second messenger, cyclic AMP, to activate its downstream genes including transcription factors and cell cycle regulators. Treatment of NSCLC cells with short interfering RNAs for growth hormone secretagogue receptor or neurotensin receptor 1 suppressed the expression of those genes and the growth of NSCLC cells. These data strongly implied that targeting the NMU signaling pathway would be a promising therapeutic strategy for the treatment of lung cancers.

A novel human tRNA-dihydrouridine synthase involved in pulmonary carcinogenesis

An increased level of dihydrouridine in tRNA(Phe) was found in human malignant tissues nearly three decades ago, but its biological significance in carcinogenesis has remained unclear. Through analysis of genome-wide gene-expression profiles among non-small cell lung carcinomas (NSCLC), we identified overexpression of a novel human gene, termed hDUS2, encoding a protein that shared structural features with tRNA-dihydrouridine synthases (DUS). The deduced 493-amino-acid sequence showed 39% homology to the dihydrouridine synthase 2 enzyme (Dus2) of Saccharomyces cerevisiae and contained a conserved double-strand RNA-binding motif (DSRM). We found that hDUS2 protein had tRNA-DUS activity and that it physically interacted with EPRS, a glutamyl-prolyl tRNA synthetase, and was likely to enhance translational efficiencies. A small interfering RNA against hDUS2 transfected into NSCLC cells suppressed expression of the gene, reduced the amount of dihydrouridine in tRNA molecules, and suppressed growth. Immunohistochemical analysis showed significant association between higher levels of hDUS2 in tumors and poorer prognosis of lung cancer patients. Our data imply that up-regulation of hDUS2 is a relatively common feature of pulmonary carcinogenesis and that selective suppression of hDUS2 enzyme activity and/or inhibition of formation of the hDUS2-tRNA synthetase complex could be a promising therapeutic strategy for treatment of many lung cancers.

Phosphorylation and activation of cell division cycle associated 8 by aurora kinase B plays a significant role in human lung carcinogenesis

Through genome-wide gene expression analysis of lung carcinomas, we detected in the great majority of lung cancer samples cotransactivation of cell division cycle associated 8 (CDCA8) and aurora kinase B (AURKB), which were considered to be components of the vertebrate chromosomal passenger complex. Immunohistochemical analysis of lung cancer tissue microarrays showed that overexpression of CDCA8 and AURKB was significantly associated with poor prognosis of lung cancer patients. AURKB directly phosphorylated CDCA8 at Ser(154), Ser(219), Ser(275), and Thr(278) and seemed to stabilize CDCA8 protein in cancer cells. Suppression of CDCA8 expression with small interfering RNA against CDCA8 significantly suppressed the growth of lung cancer cells. In addition, functional inhibition of interaction between CDCA8 and AURKB by a cell-permeable peptide corresponding to 20-amino acid sequence of a part of CDCA8 (11R-CDCA8(261-280)), which included two phosphorylation sites by AURKB, significantly reduced phosphorylation of CDCA8 and resulted in growth suppression of lung cancer cells. Our data imply that selective suppression of the CDCA8-AURKB pathway could be a promising therapeutic strategy for treatment of lung cancer patients.

Increased Expression of Insulin-like Growth Factor-II Messenger RNA–Binding Protein 1 Is Associated with Tumor Progression in Patients with Lung Cancer

PURPOSE

To identify novel biomarkers and therapeutic targets for lung cancers, we screened for genes that were highly transactivated in a large proportion of non-small cell lung cancers (NSCLC) using a cDNA microarray representing 27,648 genes.

EXPERIMENTAL DESIGN

A gene encoding insulin-like growth factor-II mRNA-binding protein 1 (IMP-1) was selected as a candidate (> or =3-fold expression than in normal lung tissue in about 70% of NSCLCs). Tumor tissue microarray was applied to examine expression of IMP-1 protein in archival lung cancer samples from 267 patients and investigated its clinicopathologic significance. A role of IMP-1 in cancer cell growth and/or survival was examined by small interfering RNA experiments. Cellular invasive activity of IMP-1 on mammalian cells was examined using Matrigel assays. mRNAs associated with IMP-1 in cancer cells were also isolated by RNA immunoprecipitation followed by cDNA microarray analysis.

RESULTS

Positive immunostaining of IMP-1 was correlated with male (P = 0.0001), tumor size (P = 0.0003), non-adenocarcinoma histology (P < 0.0001), smoking history (P = 0.0005), non-well-differentiated tumor grade (P = 0.0001), and poor prognosis (P = 0.0053). Suppression of IMP-1 expression with small interfering RNA effectively suppressed growth of NSCLC cells. In addition, we identified that exogenous expression of IMP-1 increased the migratory activity of mammalian cells. IMP-1 was able to bind to mRNAs encoding a variety of proteins involved in signal transduction, cell cycle progression, cell adhesion and cytoskeleton, and various types of enzymatic activities.

CONCLUSIONS

These results suggest that IMP-1 expression is likely to play important roles in lung cancer development and progression, and that IMP-1 is a prognostic biomarker and a promising therapeutic target for lung cancer.

Identification of Myc-associated protein with JmjC domain as a novel therapeutic target oncogene for lung cancer

Through genome-wide expression profile analysis for non-small cell lung cancers (NSCLC), we found overexpression of a Myc-associated protein with JmjC domain (MAPJD) gene in the great majority of NSCLC cases. Induction of exogenous expression of MAPJD into NIH3T3 cells conferred growth-promoting activity. Concordantly, in vitro suppression of MAPJD expression with small interfering RNA effectively suppressed growth of NSCLC cells, in which MAPJD was overexpressed. We found four candidate MAPJD target genes, SBNO1, TGFBRAP1, RIOK1, and RASGEF1A, which were the most significantly induced by exogenous MAPJD expression. Through interaction with MYC protein, MAPJD transactivates a set of genes, including kinases and cell signal transducers that are possibly related to proliferation of lung cancer cells. As our data imply that MAPJD is a novel member of the MYC transcriptional complex and its activation is a common feature of lung cancer, selective suppression of this pathway could be a promising therapeutic target for treatment of lung cancers.

Left upper lobectomy can be a risk factor for thrombosis in the pulmonary vein stump

Background

Thrombosis in the left upper pulmonary vein stump after left upper lobectomy is a very rare but important complication because it occurs in the systemic circulation system. We previously made the first ever report on the frequency and risk factors of thrombosis in the pulmonary vein stump after lobectomy. In this study, we conducted an investigation in a different hospital to determine whether this was a common complication.

Methods

From 2008 to 2012, 151 patients who underwent lobectomy and following enhanced CT within 2 years after the operation were studied. Postoperative contrast-enhanced CT imaging was retrospectively checked.

Results

We found thrombosis in the pulmonary vein stump in 5 of the 151 patients (3.3%). All 5 patients underwent left upper lobectomy (17.9% of the patients who underwent left upper lobectomy). These 5 patients did not have infarction of any vital organ. The thrombus was disappeared several months later on contrast-enhanced CT in 3 patients and followed in 2 patients. On univariate analysis, there was a significant difference only in the operative procedure (p < 0.001).

Conclusions

Thrombosis in the pulmonary vein stump occurred with high frequency in patients who underwent left upper lobectomy. Because the frequency of thrombosis in this study was the same as in our previous report, this might be a common complication.

Curvature of the lumbar spine as a consequence of mechanical necessities in Japanese macaques trained for bipedalism

If trained to walk bipedally at a juvenile age and over periods of some months or years, Japanese monkeys gradually acquire a pronounced lordosis of the lumbar spine. This lordosis persists even in the 'normal', pronograde posture of these animals. It is due to a relative increase of the ventral lengths of the vertebral bodies. This morphological change is clearly an adaptation to the mechanical necessities of the upright body posture. Our result is in complete accordance with the development of a lordosis in human children between 1 and 5 years, as described recently by others.

Postcranial skeleton of a macaque trained for bipedal standing and walking and implications for functional adaptation

The postcranial skeleton of a Japanese macaque that had been trained for bipedalism over an 11-year period was studied. Considerable modifications in the hindlimb bones caused by bipedal postural and locomotor behaviour were observed. Changes occurred in joint morphology, articular dimensions and shape-dependent strength of long bones, reflecting the causal relationship between function and morphology. However, the conditions under which the modifications are developed are somewhat different from those in humans, as the monkey's bipedalism is distinct from that of humans. The modifications seem to result from a compromise between functional requirements and the genetically determined anatomy of the essentially quadrupedal monkey.

Blood stasis may cause thrombosis in the left superior pulmonary vein stump after left upper lobectomy

Background

We previously reported that arterial infarction of vital organs after lobectomy might occur only after left upper lobectomy and be caused by thrombosis in the left superior pulmonary vein stump. We hypothesized that changes in blood flow, such as blood stasis and disturbed stagnant flow, in the left superior pulmonary vein stump cause thrombosis, and this was evaluated by intraoperative ultrasonography.

Methods

From July 2013 to April 2014, 24 patients underwent lobectomy in the Steel Memorial Muroran Hospital. During the procedure, an ultrasound probe was placed at the pulmonary vein stump and the velocity in the stump was recorded with pulse Doppler mode. The peak velocity and the presence of spontaneous echo contrast in the stump were evaluated. After the operation, the patients underwent contrast-enhanced CT within 3 months.

Results

The operative procedures were seven left upper lobectomies, four left lower lobectomies, seven right upper lobectomies, and six right lower lobectomies. Blood flow was significantly slower in the left superior pulmonary vein stump than in the right pulmonary vein stumps. However, that was not significantly slower than that in the left inferior pulmonary vein stump. Spontaneous echo contrast in the pulmonary vein stump was seen in three patients who underwent left upper lobectomy. Of the three patients with spontaneous echo contrast, two patients developed thrombosis in the left superior vein stump within 3 months after the operation. There was no patient who developed arterial infarction.

Conclusions

In patients who underwent left upper lobectomy, intraoperative ultrasonography to evaluate blood flow and the presence of spontaneous echo contrast in the left superior pulmonary vein stump may be useful to predict thrombosis that may cause arterial infarction.

Electronic supplementary material

The online version of this article (doi:10.1186/s13019-014-0159-8) contains supplementary material, which is available to authorized users.

Proteomic analysis of serum, outflow dialysate and adsorbed protein onto dialysis membranes (polysulfone and pmma) during hemodialysis treatment using SELDI-TOF-MS

AIMS

Alterations in the profiling of peptides and proteins in the serum, outflow dialysate and adsorbed protein on the dialysis membrane were investigated.

METHODS

Alterations in the protein profiling of routine hemodialysis using polysulfone (TS-UL) and PMMA (moderate flux membrane of polymethylmethacrylate: BK-U) in 8 patients and that of adsorption onto polysulfone and PMMA membranes in 4 patients were evaluated by SELDI-TOF-MS and ProteinChip array. Mass-to-charge ratios (m/z) between 2,000 and 120,000 were analyzed.

RESULTS

The protein with a relative intensity of m/z 11,730 measured by SELDI-TOF-MS was present in a small amount in the outflow dialysate and in a large amount in adsorption (identified as beta2-microglobulin) onto PMMA membrane. Unexpectedly, 68 molecular masses of peptides that were adsorbed more onto polysulfone than onto PMMA membrane were observed. There were more peptides less than m/z 11,730 adsorbed onto polysulfone membrane than onto PMMA membrane. Dominant peaks, m/z 6,629 and 6,431 adsorbed onto polysulfone membrane were identified as apolipoprotein CI and truncated apolipoprotein CI, respectively. 37 proteins with molecular weights larger than m/z 11,730 showed greater filtration through PMMA membrane than through polysulfone membrane. 149 molecular masses that were adsorbed onto PMMA or more onto PMMA membrane than onto polysulfone membrane were observed.

CONCLUSION

This experiment suggests that membrane adsorption is an important mechanism for the removal of middle-molecular-weight proteins by hemodialysis using not only PMMA membrane but also polysulfone membrane. Adsorption of peptide or protein onto a dialysis membrane may depend not only on the membrane material, but also on the peptide or protein.

Prevalence of Salmonella, Yersinia and Campylobacter spp. in feral raccoons (Procyon lotor) and masked palm civets (Paguma larvata) in Japan

To estimate the public and animal health risk that alien species pose, the prevalence of Salmonella, Yersinia, and Campylobacter spp. in feral raccoons (Procyon lotor, n = 459) and masked palm civets (Paguma larvata, n = 153), which are abundant alien species in Japan, was investigated in urban and suburban areas of Japan. Salmonella enterica was detected from 29 samples [26 raccoons, 5.7%, 95% confidence interval (CI) 7.8–3.5%; three masked palm civets, 2.0%, 95% CI 4.2–0%]. Many of the isolates belonged to serovars that are commonly isolated from human gastroenteritis patients (e.g. S. Infantis, S. Typhimurium, and S. Thompson). The antimicrobial susceptibility test showed that 26.9 % of the isolates from raccoons were resistant to at least one antimicrobial agent, whereas none of the isolates from masked palm civets were resistant. Yersinia sp. was detected from 193 samples (177 raccoons, 38.6%, 95% CI 43.0–34.1%; 16 masked palm civets, 10.5%, 95% CI 15.3–5.6%). All virulent Yersinia strains belonged to Yersinia pseudotuberculosis, which was isolated from seven (1.5%, 95% CI 2.6–0.4%) raccoons and six (3.9%, 95% CI 7.0–0.8%) masked palm civets. According to the detection of virulence factors, all the Y. pseudotuberculosis isolates belonged to the Far Eastern systemic pathogenicity type. Campylobacter spp. was detected from 17 samples (six raccoons, 1.3%, 95% CI 2.3–0.3%; 11 masked palm civets, 7.2%, 95% CI 11.3–3.1%). Among these, three isolates from raccoons were identified as C. jejuni. These results showed that these pathogens can be transmitted by human activities, other wild animals, and the environment to feral raccoons and masked palm civets, and vice versa. As these animals have omnivorous behaviour and a wide range of habitats, they can play an important role in the transmission of the enteric pathogens.

Immunophenotypic difference of keratin expression in normal mammary glandular cells from five different species

The immunohistochemical reactivity of human, monkey, shrew, rat and mouse normal mammary glands was examined using methacarn-fixed paraffin-embedded specimens and acetone-fixed frozen sections using the avidinbiotin-peroxidase method for cell phenotype comparison. Actin was visualized using anti-smooth muscle actin antibody and keratin expression was determined by employing 12 different monoclonal antibodies. All these antibodies cross-reacted specifically with the species examined. Basal (myoepithelial) cells from all species showed muscle-specific actin according to reactivity with HHF35 monoclonal antibody. Keratin expression showed significant phenotypic differences among species. In human and monkey, AEL-KS2, KL1, CK8.13, AE3 and 34BE12 stained luminal cells as well as basal cells. AE1, RPN1165, CK4.62, 35BE11, M20 and RPN1162 labeled only luminal cells whereas 312C8-1 preferentially bound to basal cells. In shrews, AEL-KS2, CK8.13 and AE3 reacted to both cell types, AE1 reacted only with luminal cells, and 35BE12 and 312C8-1 selectively stained basal cells. In rodents, AEL-KS2 reacted to both cell types, CK8.13, AE3, 34BE12 and 312C8-1 stained rat basal cells, and 34BE12 and 312C8-1 reacted to mouse basal cells. The data represents cytoskeletal differences among species.

Chlorinated persistent organic pollutants in black-tailed gulls (Larus crassirostris) from Hokkaido, Japan

Concentrations and patterns of several chlorinated persistent organic pollutants (POPs) including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) and DDTs, HCHs, CHLs and HCB were determined in black-tailed gulls (Larus crassirostris) from breeding grounds in Hokkaido, Japan. Subcutaneous fat of five adult gulls was analyzed, which had different concentrations of target compounds, whereas gull eggs contained similar concentrations of target compounds. Similar congener profiles were found between adult gulls and eggs. The concentrations of non-ortho PCBs varied from 3.4 to 13.5 ng/g lipid weight (lw) in the fat of black-tailed gulls and from 2.4 to 7.4 ng/g lw in their eggs. 2,3,7,8-PCDD/Fs occurred at relatively lower concentrations than non-ortho PCB congeners in both adult gulls and eggs. The total TEQs (toxic equivalents, PCDD/Fs+ non-ortho PCB) ranged from 0.26 to 1.0 ng/g lw in adult gulls and ranged from 0.19 to 0.58 ng/g lw in eggs.

Risk Factors for Difficult Laparoscopic Cholecystectomy in Acute Cholecystitis

Background and Objectives:

Factors that contribute to difficult laparoscopic cholecystectomy (LC) in acute cholecystitis (AC) that would affect the performance of early surgery remain unclear. The purpose of this study was to identify such risk factors.

Methods:

One hundred fifty-four patients who underwent LC for AC were retrospectively analyzed. The patients were categorized into early surgery and delayed surgery. Factors predicting difficult LC were analyzed for each group. The operation time, bleeding, and cases of difficult laparoscopic surgery (CDLS)/conversion rate were analyzed as an index of difficulty. Analyses of patients in the early group were especially focused on 3 consecutive histopathological phases: edematous cholecystitis (E), necrotizing cholecystitis (N), suppurative/subacute cholecystitis (S).

Results:

In the early group, the CDLS/conversion rate was highest in necrotizing cholecystitis. Its rate was significantly higher than that of the other 2 histopathological types (N 27.9% vs E and S 7.4%; P = .037). In the delayed-surgery group, a higher white blood cell (WBC) count and older age showed significant correlations with the CDLS/conversion rate (P = .034 and P = .004).

Conclusion:

In early surgery, histopathologic necrotizing cholecystitis is a risk factor for difficult LC in AC. A higher WBC count and older age are risk factors for delayed surgery.

Long-term natural history of acquired cystic disease of the kidney

Patients with acquired cystic disease of the kidney (ACDK) were followed longitudinally over an average of 21.7 +/- 5.4 years to determine the natural history of the disease; that is, how big the kidneys become, when the kidney size reaches a plateau, and when the size regresses. Twenty-seven male and 20 female patients with chronic glomerulonephritis treated at our hospital were investigated. CT scans were performed once a year and kidney volume was measured. Two different quadratic curves with a node of 5.2 years for males and 2.5 years for females after the start of hemodialysis were fitted to log-transformed kidney volume to the duration of hemodialysis using a linear mixed model. The maximum kidney volume in male patients was obtained 21.1 years after the start of hemodialysis using this model. Peak values of kidney volume were demonstrated in 19 of 26 cases during the observation period. The median peak value (interquartile range) of bilateral kidney volumes was 274 (165-849) mL/1.73 m(2) occurring 19.1 +/- 4.5 years after the start of dialysis. In one male patient who had undergone nephrectomy due to renal cell carcinoma and in two of the remaining 26 male patients, the maximum kidney volume of 782 (residual kidney), 1151, and 1129 mL regressed to 428, 616, and 847 mL (reduction rate: 45.3, 46.5, and 25.0%) at 20.6, 25.4, and 23.1 years after the start of hemodialysis, respectively. Kidney enlargement due to ACDK reached a plateau after 21.1 years of hemodialysis in the male patients. Partial regression of severe ACDK may occur naturally after long-term hemodialysis without renal transplantation.