Ileo-ileal fistula with severe malnutrition caused by strangulated ileus surgery while preserving ischemic ileum: A case report

INTRODUCTION

Entero-enteric fistulas are rare complications that occur in patients with inflammatory bowel disease and other intestinal diseases. In this report, we present an ileo-ileal fistula accompanied by severe malnutrition caused by strangulated ileus surgery while preserving the ischemic ileum in a very elderly patient.

CASE PRESENTATION

A 90-year-old woman underwent emergency surgery without bowel resection for strangulated ileus in another hospital. Minor abdominal pain and slight fever persisted after surgery. She lost weight, losing approximately 10 kg within half a year. She gradually became difficult to move due to dyspnea upon exertion and generalized edema and visited at our hospital. Pleural effusions, ascites and severe malnutrition were observed. An elastic hard mass with mild tenderness was palpated in her abdomen. Computed tomography showed a loop-like ileum and ileo-ileal fistula with adjacent fat stranding. We performed a partial small bowel resection. The resected specimen demonstrated an ileo-ileal fistula and circumferential ulceration in the loop-like adhesion. After the operation, the nutrition status was resolved immediately without any medications.

DISCUSSION

In cases of strangulated ileus, there are no deterministic criteria for evaluating intestinal blood flow. This is the first report of ileo-ileal fistula onset after surgery for strangulated ileus without intestinal resection. Furthermore, this fistula caused severe malnutrition duo to chronic inflammation, ulcer formation, and the blind-loop syndrome.

CONCLUSIONS

When preserving the intestinal tract in the operation of strangulated ileus, the occurrence of entero-enteric fistulas should be considered. Since malnutrition in the elderly is a serious problem, it should be treated promptly.

Early progression of brain atrophy in patients with anti-N-methyl-D-aspartate receptor encephalitis: Case reports

BACKGROUND

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis responds to immunnotherapy, and approximately 80% of patients with this disorder fully recover or have only minor sequelae. Brain magnetic resonance imaging (MRI) does not show a specific abnormality, but some patients have progressive cerebral atrophy. The cerebral atrophy can become reversible after clinical improvement.

METHODS

We describe 3 patients with diffuse cerebral atrophy (DCA) on serial brain MRI.

RESULTS

Two women had the typical spectrum of this disorder, and one man had mainly psychiatric symptoms. In a woman with an ovarian tumor, DCA was reversible and DCA developed within about a half month. In another woman without a tumor, DCA was evident within 19 days and had progressed over the course of 4 years. The titers of anti-NMDAR antibodies in serum and cerebrospinal fluid (CSF) initially decreased, and low titers of the antibodies persisted. In a man without a tumor, DCA progressed within 14 days, and during this short period, he did not receive prolonged treatment with corticosteroids, various antiepileptic agents, or propofol, and he was free of seizures and ventilatory support.

CONCLUSION

Not only a woman but also a man with anti-NMDAR encephalitis can have DCA in the early phase of this disorder. However, DCA can be reversible after clinical improvements. The early progression of DCA is not necessarily a poor prognostic factor.

Risk of Unsuccessful Noninvasive Ventilation for Acute Respiratory Failure in Heterogeneous Neuromuscular Diseases: A Retrospective Study

If invasive ventilation can be avoided by performing noninvasive mechanical ventilation (NIV) in patients with acute respiratory failure (ARF), the disease can be effectively managed. It is important to clarify the characteristics of patients with neuromuscular diseases in whom initial NIV is likely to be unsuccessful. We studied 27 patients in stable neuromuscular condition who initially received NIV to manage fatal ARF to identify differences in factors immediately before the onset of ARF among patients who receive continuous NIV support, patients who are switched from NIV to invasive ventilation, and patients in whom NIV is discontinued. Endpoints were evaluated 24 and 72 hours after the initiation of NIV. After 24 hours, all but 1 patient with amyotrophic lateral sclerosis (ALS) received continuous NIV support. 72 hours later, 5 patients were switched from NIV to invasive ventilation, and 5 patients continued to receive NIV support. 72 hours after the initiation of NIV, the proportion of patients with a diagnosis of ALS differed significantly among the three groups (P=0.039). NIV may be attempted to manage acute fatal respiratory failure associated with neuromuscular diseases, but clinicians should carefully manage the clinical course in patients with ALS.

Once-weekly teriparatide in hemodialysis patients with hypoparathyroidism and low bone mass: a prospective study

Once-weekly 56.5-μg teriparatide treatment was significantly associated with the increase in lumbar spine bone mineral density at 48 weeks among hemodialysis patients with hypoparathyroidism and low bone mass; however, discontinuation of treatment because of adverse events was frequently observed. Careful monitoring for adverse events should be required.

INTRODUCTION

Once-weekly 56.5-μg teriparatide is reportedly effective for treating osteoporotic patients without renal insufficiency. However, little is known about the efficacy and safety of once-weekly teriparatide in hemodialysis patients.

METHODS

We conducted a 48-week prospective, observational cohort study including 22 hemodialysis patients aged 20 years or older with hypoparathyroidism and low bone mass who received once-weekly teriparatide at 56.5 μg at a tertiary care hospital between January 2013 and January 2015. Primary outcomes were within-subject percent changes of bone mineral density (BMD) at the lumbar spine, femoral neck, and distal one-third radius at 24 and 48 weeks. Secondary outcomes included percent changes of serum bone turnover markers (osteocalcin, bone-specific alkaline phosphatase (BAP), N-terminal propeptide of procollagen type 1 (P1NP), and tartrate-resistant acid phosphatase 5b (TRAP-5b)). Adverse events were evaluated.

RESULTS

The BMD increased at the lumbar spine by 3.3 ± 1.9 % (mean ± SEM) and 3.0 ± 1.8 % at 24 and 48 weeks but not in the femoral neck and distal one-third radius. Serum osteocalcin, BAP, and P1NP increased significantly at 4 weeks, maintaining higher concentrations up to 48 weeks, although TRAP-5b decreased gradually during treatment. The baseline BAP was significantly associated with the 48-week percent change in lumbar spine BMD. Transient hypotension was the most common adverse event. Ten patients discontinued treatment because of adverse events.

CONCLUSIONS

Once-weekly teriparatide was associated with increased lumbar spine BMD in hemodialysis patients with hypoparathyroidism and low bone mass. Careful monitoring should be required for treatment of such patients.

Helicobacter cinaedi bacteremia in four renal transplant patients: clinical features and an important suggestion regarding the route of infection

Helicobacter cinaedi can cause bacteremia mainly in immunocompromised patients. We present the clinical characteristics of H. cinaedi bacteremia in 4 renal transplant patients. Interestingly, all cases showed triggers of bacterial translocation: 2 cases developed after colonic perforation caused by diverticulitis, 1 case developed post cholecystectomy, and the remaining patient had chronic diarrhea. Accordingly, bacterial translocation caused by severe gastrointestinal complication could be a cause of H. cinaedi bacteremia.

Colovesical Fistula After Renal Transplantation: Case Report

Colovesical fistula is a relatively rare condition that is primarily related to diverticular disease. There are few reports of colovesical fistula after renal transplantation. We report of a 53-year-old man who was diagnosed with colovesical fistula after recurrent urinary tract infection, 5 months after undergoing cadaveric renal transplantation. Laparoscopic partial resection of the sigmoid colon with the use of the Hartmann procedure was performed. Six months after that surgery, there was no evidence of recurrent urinary tract infection and the patient's renal graft function was preserved. Physicians should keep colovesical fistula in mind as a cause of recurrent urinary tract infection in renal transplant recipients, especially in those with a history of diverticular disease.

Impact of tubulointerstitial lesions on anaemia in patients with biopsy-proven diabetic nephropathy

AIMS

To investigate the relationship between the progression of anaemia and renal pathological findings in patients with diabetic nephropathy.

METHODS

A total of 223 patients with diabetes underwent renal biopsy from 1985 to 2010 and were confirmed to have pure diabetic nephropathy according to the recent classification, of whom 113 (baseline haemoglobin ≥ 11 g/dl) were enrolled in the study. Linear regression analysis was used to estimate the changes in haemoglobin levels during the follow-up period.

RESULTS

In a multivariate model adjusted for clinical and histopathological variables, higher interstitial fibrosis and tubular atrophy scores were more strongly associated with a decrease in haemoglobin levels than were lower scores. Compared with an interstitial fibrosis and tubular atrophy score of 0, the standardized coefficients for interstitial fibrosis and tubular atrophy scores of 1, 2 and 3 were 0.20 (95% CI -0.31 to 0.93), 0.34 (95% CI -0.22 to 1.34) and 0.47 (95% CI 0.07 to 1.96), respectively, whereas a higher glomerular class, a higher vascular lesion score and the presence of exudative lesions were not strongly correlated with the decrease in haemoglobin.

CONCLUSIONS

Tubulointerstitial lesions that are more advanced are significantly associated with the progression of anaemia in patients with diabetic nephropathy after adjustment for numerous covariates. This finding suggests that tubulointerstitial lesions may be a useful prognostic indicator for anaemia in patients with diabetic nephropathy, and that decreased erythropoietin production attributable to the progression of tubulointerstitial lesions is a major cause of anaemia in these patients.

Bone histomorphometry in a long-term hemodialysis patient with hypoparathyroidism and sarcoidosis

A bone biopsy specimen in a long-term hemodialysis patient with sarcoidosis coexisting with severe hypoparathyroidism has demonstrated that a persistent near physiological level of 1,25-dihydroxyvitamin D3 contributes to the preservation of bone remodeling and has the potential to retard the development of vascular calcification and atherosclerosis. Sarcoidosis-related hypercalcemia and hypoparathyroidism, which is characterized by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) overproduction, is rarely seen in hemodialysis patients. Herein, we describe a 60-year-old Japanese woman on hemodialysis for 35 years who presented with malaise and hypercalcemia. Severe hypoparathyroidism without parathyroidectomy and a preserved 1,25(OH)2D3 level were detected. Computed tomography showed bilateral axillary lymphadenopathy and minimal aortic and soft tissue calcification. The axillary node biopsy led to a definite diagnosis of sarcoidosis. A bone biopsy specimen obtained from the right iliac crest showed remodeling of normal lamellar bone with scalloped cement lines and clear double labeling by tetracycline on fluorescence microscopy. Histomorphometric analysis revealed that the bone formation rate was preserved (30.0 %/year), together with a decrease of osteoid volume (5.75 %) and fibrous volume (0 %), indicating that the patient did not have adynamic bone disease and only showed mild disease. This is the first documented case of sarcoidosis-related hypercalcemia associated with severe hypoparathyroidism in a long-term hemodialysis patient who underwent bone histomorphometry. Our findings suggest that, in hemodialysis patients with sarcoidosis coexisting with severe hypoparathyroidism, a persistent near physiological level of 1,25(OH)2D3 contributes to the preservation of bone remodeling and has the potential to retard the development of vascular calcification and atherosclerosis.

Preoperative low-dose steroid can prevent respiratory insufficiency after thymectomy in generalized myasthenia gravis

BACKGROUND

Postoperative respiratory insufficiency (PRI) in myasthenia gravis (MG) often occurs within several days after thymectomy and remains problematic. In limited studies reporting that preoperative steroids prevented PRI in patients with MG, high doses of steroids were used and detailed information on the use of steroids is limited. Because high-dose steroids significantly increase the risk of adverse effects, we studied 37 patients with generalized MG to investigate whether low-dose steroids might prevent PRI.

METHODS

The low-dose steroids were started orally, and the dose was gradually increased to the maximum level (30 mg/day). Immediately before thymectomy, patients received the maximum dose of oral steroids daily. PRI was defined as the development of restrictive dysfunction requiring mechanical ventilation within 3 days after thymectomy and total postoperative mechanical ventilation support time of >24 h.

RESULTS

The rate of PRI in the low-dose steroid use group was significantly lower than that in the no-steroid use group. The postoperative stay in the intensive care unit was shorter in the steroid use group.

CONCLUSIONS

Extended thymectomy is a well-accepted surgical treatment for selected patients with MG. However, PRI remains problematic. Our results suggest that not only preoperative high-dose steroid treatment, but also low-dose steroid treatment can prevent PRI.

Long-term complete remission of multiple extranodal natural killer/T-cell-type posttransplant lymphoproliferative disorder after surgical resection: a case report

BACKGROUND

Posttransplant lymphoproliferative disorder (PTLD) is a life-threatening complication of organ transplantation that results from immunosuppression therapy. Most cases of PTLD derive from the B-cell lineage. T-cell PTLD, particularly natural killer (NK)/T-cell PTLD, is quite rare; only a few cases have been described.

CASE REPORT

A 42-year-old woman received a living-related renal allograft from her father. Sixteen years after transplantation, the patient presented with a 1-week history of low-grade fever and epigastralgia. Computed tomography revealed intestinal masses and a right upper lung lobe mass. Gallium scintigraphy showed uptake in the abdominal mass. Epstein-Barr virus-related antibody was not detected in the patient's serum sample. We performed extirpation of the jejunum and ileum tumors. The pathologic findings showed that these 2 tumors were NK/T-cell lymphoma. After the operation, the lung mass rapidly enlarged, and right upper lobectomy was performed. The right upper lung lobe tumor showed the same histopathologic findings as the small bowel tumor. The final histologic diagnosis was established as multiple extranodal NK/T cell type PTLD of the small bowel and right upper lung lobe.

CONCLUSIONS

After reduction of the immunosuppressive agent, no recurrence of PTLD has been observed for the past 9 years.

Identification and characterization of novel multiple bacteriocins produced by Lactobacillus sakei D98

AIM

To characterize novel multiple bacteriocins produced by Lactobacillus sakei D98.

METHODS AND RESULTS

Lactobacillus sakei D98 isolated from Shubo (rice malt) produced at least three bacteriocins. Using three purification steps, three novel antimicrobial peptides termed sakacin D98a, sakacin D98b and sakacin D98c were purified from the culture supernatant. Amino acid and DNA sequencing analysis revealed that the sakacins D98a, D98b and D98c are novel class IIa-like or class IId bacteriocins. In particular, sakacin D98b has a variant pediocin-box sequence, YANGVXC (with Ala instead of Gly), and a different location for the disulfide bridge (Cys(11) and Cys(18)) from that found in other class IIa bacteriocins.

CONCLUSIONS

Three novel bacteriocins were identified from Lactobacillus sakei D98. Their antimicrobial spectra and intensities indicate that these sakacins would have different modes of action. In addition, sakacin D98b showed low inhibitory activity against Listeria, probably due to the differences in amino acids and position of the disulfide bridge compared with the other class IIa bacteriocins.

SIGNIFICANCE AND IMPACT OF STUDY

Sakacins D98a and D98c are novel bacteriocins belonging to class IId bacteriocins. On the other hand, sakacin D98b, a class IIa-like bacteriocin, has a unique internal structure and activity spectrum.

Dropped head with positive intravenous edrophonium, progressing to myasthenia gravis

'Dropped head syndrome' (DHS) may be associated with a variety of neurological diseases. The absence of neurological clues to the underlying cause of DHS can make management particularly challenging. We review six patients who presented with only DHS, responded to intravenous edrophonium and turned out to have myasthenia gravis (MG) including similar patients who were previously documented. Six patients presented with neck weakness and three had bulbar symptoms. Acetylcholine receptor (AchR) was positive in four patients. One patient had thymoma. The interval from the onset of DH to the presentation of typical MG features was shorter in patients who tested positive for anti-Ach antibody (1-2 months) than in patients who tested negative for anti-AchR antibody (13 months, 4 years). Our results suggest that patients with DHS responding to intravenous edrophonium might turn out to have MG and such patients might respond to a combination of anticholinesterase agents and steroids.

Clinical analysis and outcomes of amyotrophic lateral sclerosis with demyelinating polyneuropathy

Abnormalities of both motor and sensory nerve action potentials, similar to those found in demyelinating polyneuropathy, may occur in patients with amyotrophic lateral sclerosis (ALS). We analyzed the clinical features of unusual ALS patients with demyelinating polyneuropathy (DPN) to delineate the characteristics and outcomes of this rare condition. We reviewed three ALS patients with DPN who were confirmed to meet the electrophysiological nerve conduction criteria for DPN among 157 patients with ALS. At the initial neurological examination, one patient had both subjective sensory symptoms and abnormal results of sensory examinations, and one patient had sensory symptoms. Motor weakness of the limbs was present in all patients, and fasciculation was present in two patients. Anti-GalNAc-GD1a IgG antibodies were evident in one. Sural nerve biopsy showed a moderate, marginal reduction in myelin thickness, and teased fiber analysis revealed segmental demyelination and remyelination, but axonal degeneration was found in one patient. The mean interval from disease onset to respiratory failure or death in our three patients and seven previously documented ALS patients with DPN was 43.1 ± 18.7 months. Our findings suggest that survival in ALS with DPN is similar to that in classic ALS.

Characterization and identification of weissellicin Y and weissellicin M, novel bacteriocins produced by Weissella hellenica QU 13

AIMS

To identify and characterize novel bacteriocins from Weissella hellenica QU 13.

METHODS AND RESULTS

Weissella hellenica QU 13, isolated from a barrel used to make Japanese pickles, produced two novel bacteriocins termed weissellicin Y and weissellicin M. The primary structures of weissellicins Y and M were determined, and their molecular masses were determined to be 4925·12 and 4968·40 Da, respectively. Analysis of the DNA sequence encoding the bacteriocins revealed that they were synthesized and secreted without N-terminal extensions such as leader sequences or sec signal peptides. Weissellicin M showed significantly high and characteristic homology with enterocins L50A and L50B, produced by Enterococcus faecium L50, while weissellicin Y showed no homology with any other known bacteriocins. Both bacteriocins showed broad antimicrobial spectra, with especially high antimicrobial activity against species, which contaminate pickles, such as Bacillus coagulans, and weissellicin M showed relatively higher activity than weissellicin Y. Furthermore, the stability of weissellicin M against pH and heat was distinctively higher than that of weissellicin Y.

CONCLUSIONS

Weissella hellenica QU 13 produced two novel leaderless bacteriocins, weissellicin Y and weissellicin M, and weissellicin M exhibited remarkable potency that could be employed by pickle-producing industry.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study is the first report, which represents a complete identification and characterization of novel leaderless bacteriocins from Weissella genus.

[Suspected measles encephalitis caused by modified measles that was difficult to diagnose: a case report]

A 72-year-old man with subacute right upper limb palsy was diagnosed with cerebral infarction at another hospital. However, the head magnetic resonance imaging (MRI) scans showed no abnormalities. He was later transferred to our hospital because of cognitive dysfunctions. Because his symptoms had gradually worsened, a second head MRI was performed on admission. The scans showed an abnormality in the left frontal-parietal lobe, and the serum measles IgM level was elevated. Measles encephalitis was consequently diagnosed and steroid pulse therapy was immediately initiated. The patient recovered with no limb palsy or cognitive dysfunctions. With widespread administration of the measles vaccine, we expect that the incidence of modified measles will increase in the future. Hence the serum titer of the measles virus should be measured when patients with subacute meningoencephalitis of unclear origin are identified.

Hepatitis C virus-related kidney disease: various histological patterns

BACKGROUND

Although hepatitis C virus (HCV) infection is known to be associated with Type 2 cryoglobulinemic glomerulopathy (CG), only a few reports about other types of nephropathy have been published.

METHODS

68 HCV antibody positive patients in whom renal biopsy had been performed for persistent proteinuria, hematuria, and/or renal dysfunction between 1992 and 2008 at our institute were included. The histological, clinical and laboratory characteristics including the age, gender, hypertension, diabetes mellitus, liver histology (chronic hepatitis or liver cirrhosis), HCV-RNA, HCV genotype, splenomegaly, gastroesophageal varices, serum creatinine, hemoglobin, platelet count, rheumatoid factor, cryoglobulin, IgG, IgA, IgM, CH50, C3, C4, creatinine clearance, 24-h protein excretion, and hematuria, between their nephropathy with and without immune deposition were compared.

RESULTS

Nephropathy was classified into two groups based on the detection of immune deposits by immunofluorescence microscopy: i.e., a positive group (n = 39) and a negative group (n = 29). The former group was further classified into three types of nephropathy: IgG dominant group (n = 10) (including membranous nephropathy (MN)), IgA dominant group (n = 20) (including IgA nephropathy (IgAN)), membranoproliferative glomerulonephritis (MPGN) (IgA type)), and IgM dominant group (n = 9) (MPGN apart from the IgA type). The latter group included diabetic nephropathy (n = 13), focal glomerular sclerosis (n = 4), and benign nephrosclerosis (n = 3), malignant nephrosclerosis (n = 1), tubulointerstitial nephritis (TIN) (n = 2), minimal change nephrotic syndrome (n = 1), cast nephropathy (n = 1), granulomatous TIN (n = 1), and others (n = 3). An increased serum IgM level, hypocomplementemia, splenomegaly, thrombocytopenia, liver cirrhosis, hematuria, and a high HCV RNA level were features of patients with MPGN of IgM dominant group (consistent with "CG").

CONCLUSIONS

Our results showed various histological patterns of HCV-related kidney disease and the specificity of CG, and revealed that a minority of HCV patients (n = 7) presented typical CG, while IgAN, MN, and diabetic nephropathy were more frequent.

Identification and characterization of novel multiple bacteriocins produced by Leuconostoc pseudomesenteroides QU 15

AIM

To characterize novel multiple bacteriocins produced by Leuconostoc pseudomesenteroides QU 15.

METHODS AND RESULTS

Leuconostoc pseudomesenteroides QU 15 isolated from Nukadoko (rice bran bed) produced novel bacteriocins. By using three purification steps, four antimicrobial peptides termed leucocin A (ΔC7), leucocin A-QU 15, leucocin Q and leucocin N were purified from the culture supernatant. The amino acid sequences of leucocin A (ΔC7) and leucocin A-QU 15 were identical to that of leucocin A-UAL 187 belonging to class IIa bacteriocins, but leucocin A (ΔC7) was deficient in seven C-terminal residues. Leucocin Q and leucocin N are novel class IId bacteriocins. Moreover, the DNA sequences encoding three bacteriocins, leucocin A-QU 15, leucocin Q and leucocin N were obtained.

CONCLUSIONS

These bacteriocins including two novel bacteriocins were identified from Leuc. pseudomesenteroides QU 15. They showed similar antimicrobial spectra, but their intensities differed. The C-terminal region of leucocin A-QU 15 was important for its antimicrobial activity. Leucocins Q and N were encoded by adjacent open reading frames (ORFs) in the same operon, but leucocin A-QU 15 was not.

SIGNIFICANCE AND IMPACT OF STUDY

These leucocins were produced concomitantly by the same strain. Although the two novel bacteriocins were encoded by adjacent ORFs, a characteristic of class IIb bacteriocins, they did not show synergistic activity.

Multicentric Castleman disease with secondary AA renal amyloidosis, nephrotic syndrome and chronic renal failure, remission after high-dose melphalan and autologous stem cell transplantation

Multicentric Castleman disease is a systemic lymphoproliferative disease with incomplete understood etiology. The various renal complications of this disease may include minimal change disease, mesangial proliferative glomerulonephritis, membranous glomerulonephritis and nephrotic syndrome, caused by secondary amyloidosis. In several reported cases of localized Castleman disease associated with renal amyloidosis and nephrotic syndrome, resection of organs involved by lymphoid proliferation resulted in complete remission. However, therapy of multicentric Castleman disease with renal amyloidosis is not well-established. We treated a case of a 39-year-old woman with multicentric Castleman disease complicated by nephrotic syndrome caused by secondary AA amyloidosis. The patient underwent autologous peripheral blood stem cell transplantation (auto-PBSCT), achieving complete remission. Autologous stem cell transplantation may be an attractive choice in therapy for refractory multicentric Castleman disease.

A pediatric occurrence of crescentic glomerulonephritis associated with antineutrophil cytoplasmic antibodies and mesangial IgA deposits

Antineutrophil cytoplasmic antibody-(ANCA) associated glomerulonephritis usually shows histopathologic features of pauciimmune crescentic glomerulonephritis and occurs late in life. We report a 14-year-old Japanese girl presenting with proteinuria, hematuria and mildly elevated serum creatinine. A renal biopsy specimen demonstrated crescentic glomerulonephritis, immunofluorescence showed mesangial IgA staining. Electron microscopic examination disclosed paramesangial deposits. Serum ANCA against myeloperoxidase (MPO) were detected at high titers. Myeloperoxidase-ANCA-related nephritis accompanied by IgA nephropathy is considered rare in childhood and teen years. Yet, if ANCA assays and detailed electron microscopic examination of renal specimens were performed routinely in patients with rapidly progressive glomerulonephritis, the diagnosis might be more frequent in young patients.

Ribozyme-mediated inactivation of mutant K-ras oncogene in a colon cancer cell line

Mutation of c-K-ras oncogene is an important step in progression of colon cancer. We used a hammerhead ribozyme (KrasRz) against mutated K-ras gene transcripts (codon 12, GTT) to inactivate mutant K-ras function in the colon cancer cell line SW480, harbouring a mutant K-ras gene. The beta-actin promoter-driven KrasRz sequence (pHbeta/KrasRz) was introduced into these cells (SW480/KrasRz), and we evaluated its effects on growth of the colon cancer. The gene expression of angiogenesis-related molecules (vascular endothelial growth factor and thrombospondin) was also estimated in SW480/KrasRz. KrasRz specifically and efficiently cleaved the mutant K-ras mRNA but not wild-type mRNA in vitro. SW480/KrasRz showed decreased growth rate under tissue culture conditions (P< 0.01, Dunnett's test). The xenotransplantability of SW480/KrasRz (XeSW480/KrasRz) was significantly decreased in nude mice (P< 0.05, Fisher's exact test). Tumour volume of the xenografts XeSW480/KrasRz was significantly smaller than that of XeSW480/DisKrasRz (P< 0.01, Dunnett's test). Gene expression of VEGF was suppressed in SW480/KrasRz, while TSP1 gene expression was enhanced. The SW480/KrasRz cells showed apoptosis-related features including nuclear condensation and DNA fragmentation. These results suggested that the hammerhead ribozyme-mediated inactivation of the mutated K-ras mRNA induced growth suppression, apoptosis and alteration of angiogenic factor expression.

In vivo chemosensitivity of human malignant cystosarcoma phyllodes xenografts

Malignant cystosarcoma phyllodes (MCSP) is a rare breast tumor. Chemotherapeutic regimens for treatment of MCSP have not been established. We previously established an MCSP xenograft line MC-3-JCK. In this study, we established a new MCSP xenograft line, MC-10-JCK, by serial transplantation in nude mice. We studied the chemosensitivity of these two MCSP tumor xenografts to anticancer drugs in vivo. We also examined the expression of multidrug resistance-related proteins such as p-glycoprotein (Pgp) and multidrug resistance-associated protein (MRP) by immunohistochemical analysis. These two xenografts were sensitive to doxorubicin, vincristine and cyclophosphamide in vivo. Immunohistochemically, clinical specimens and xenografts were negative for Pgp and MRP expression. These results are consistent with the chemosensitivity of human MCSP to lipophilic anticancer compounds.

Heterozygous ras mutations are preserved in serially passaged human tumor xenografts and established cell lines

We examined c-K-ras gene point mutations in human tumor xenografts and established cell lines as markers of genetic stability. Our previous study demonstrated the stability of c-K-ras gene mutations in human primary neoplasms and their tumor xenografts through serial passages in mice. In this study, we established 27 human cell lines derived from various human tumor xenografts in nude mice. Point mutation of the c-K-ras gene at codon 12 was found in 29.6% (8/27) of the cell lines, as well as in 29.6% (8/27) of the xenografts. The eight ras-mutated cell lines were derived from corresponding tumor xenografts carrying the ras mutation. Heterozygous ras gene mutation was confirmed in seven of the eight ras-mutated cell lines, as well as their corresponding xenografts. The incidence, type and heterozygosity of the c-K-ras gene mutation showed no discrepancies between the original xenografts and the established cell lines. From these findings, we concluded that point mutation of the c-K-ras gene was very stable in human tumor xenografts and established cell lines derived from the xenografts.

[A case of rheumatoid arthritis with bucillamine-induced myasthenia gravis treated by immunoadsorption therapy]

We report a case of 48-year old female with rheumatoid arthritis (RA) complicated with myasthenia gravis. In 1988, she was diagnosed of having RA, and several therapeutic drugs were administered, but her disease activity was in poor control. In July 1993, bucillamine (BU) was started at a dose of 100 mg/day, and her arthritis subsided. However, in October 1996, she was admitted with a rapidly progressive ptosis and double vision in the left eye, which became prominent in the evening. Because serum concentration of the antibody to acetylcholine receptors (AchR Ab) was elevated at 12.6 nmol/l, and the ptosis was reversed immediately after a tensilon test, ocular type myasthenia gravis (MG) was diagnosed and it was thought to have been induced by BU. Immunoadsorption therapy was started after discontinuation of this drug, and was continued for 6 months, resulting in improvement of neurological symptoms and decrease in AchR Ab level. MG has not recurred since. Although several cases of D-penicillamine (DP) induced MG are reported, only two cases are reported which were induced by BU, sulfhydryl compound which has a structure similar to DP. Since BU has been widely used as one of the disease modifying anti-rheumatic drugs in Japan, MG induced by this drug should be paid attention as one of the adverse effects.

Establishment of an adrenocortical carcinoma xenograft with normotensive hyperaldosteronism in vivo

We established a xenograft line of human adrenocortical carcinoma (ADR-1), and analyzed the hyperaldosteronism induced by the xenograft in vivo. Adrenocortical carcinoma specimens from a 25-year-old woman were subcutaneously inoculated into nude mice (BALB/c-nu/nu) followed by serial passages in vivo. ADR-1 retained the histopathological features (trabecular and sinusoid nests) seen in the primary carcinoma. The patient showed hyperaldosteronism (serum aldosterone >4000 pg/ml) and hypokalemia (serum K 2.1 mEq/l), but did not show hypertension. The nude rat (F344-rnu/rnu) bearing ADR-1 showed hyperaldosteronism (serum aldosterone 3320+/-1420 pg/ml; control 191+/-130 pg/ml) and hypokalemia (serum K 3.4+/-0.4 mEq/l; control 5.2+/-1.0 mEq/l) in vivo, and hypertension was not obvious. ADR-1 was shown immunohistochemically to retain production of human-specific corticosteroid synthetase. The xenograft ADR-1 will be useful to elucidate the regulatory mechanism of normotensive hyperaldosteronism.

Practical role of genetic profiling and preservation stock of human tumour xenograft lines as a tool in animal experiments for antitumour drug evaluation

Human tumour xenografts (HTXs) are a useful tool for animal experiments especially for evaluation of new antitumour drugs. We have been establishing HTXs, and have developed tumour chemosensitivity panels for new drug evaluation using them. With regard to quality control (problems in changes into mouse-type tumours and/or artificial cross-contamination among tumour lines), we studied genetic profiling, and effects of long-term passaging on tumour properties such as growth and chemosensitivities, and we discuss the use of cryopreservation stock of HTXs and periodic replacement in order to maintain reproducibility of the experimental results. We examined isozyme markers and DNA fingerprinting to identify species and individuality of the tumours, respectively. Growth curves and sensitivities to antitumour drugs were examined using HTXs with different passaging in nude mice. Among the tumours we maintained, five human tumours were found to have changed to mouse origin from their isozyme markers and were excluded. We identified the individuality of tumours which we used for the chemosensitivity panels by DNA fingerprinting, and their properties were stable for long-term passaging in nude mice. However, growth speed and chemosensitivities to drugs were altered with long-term passaging, although DNA fingerprint analysis did not show any obvious changes with passaging. Genetic profiling, such as isozyme markers and DNA fingerprinting, is useful to identify individuality of experimental HTXs, and tumours should be renewed periodically even when there are no signs of artificial contamination when they are used in experiments which require continuous reproducibility of experimental results.

Antagonistic effects of psycholeptic drugs on stress-induced analgesia

Stress-induced analgesia was significantly antagonized by naloxone and was dose-dependently reduced by diazepam, chlordiazepoxide, flurazepam, medazepam, nitrazepam, estazolam, phenobarbital, chlorpromazine, levomepromazine, haloperidol and propranolol. In contrast to psycholeptics, morphine substantially increased in threshold of nociceptive response in the post-stress session. Centrally acting muscle relaxants, tolperisone and carosiprodol had no substantial anti-stress effects. These results suggest that the stress-induced analgesia is probably mediated through endogenous opioids in the central nervous system. The approach used in our study provides a simple method for assessing the anti-stress action of psycholeptics.