An arachnoid granulation in the straight sinus

We report CT, MRI and angiographic findings of an arachnoid granulation in the straight sinus in a young man. Its density and signal intensity were isodense and isointense with cerebrospinal fluid on CT and MRI, respectively. The lesion appeared as a filling defect on MR venography and conventional angiography.

Dexamethasone enhances phospholipase D activity in M-1 cells

Phospholipase D (PLD) is an enzyme involved in signal transduction and widely distributed in mammalian cells. The signal transduction pathways and role for phospholipid metabolism during hormonal response in cortical collecting duct remain partly undefined. It has been reported that dexamethasone increases transepithelial transport in M-1 cells that are derived from the mouse cortical collecting duct. We investigated the expression and activity of PLD in M-1 cells. Basal PLD activity of M-1 cells cultured in the presence of dexamethasone (5 microM) was higher than in the absence of dexamethasone. Dexamethasone and ATP activated PLD in M-1 cells but phorbol ester did not stimulate PLD activity. Vasopressin, bradykinin, dibutyryl cyclic AMP, and ionomycin were ineffective in activating PLD of the cells. The PLD2 isotype was detected by immunoprecipitation but PLD1 was not detected in M-1 cells. Addition of GTPgammaS and ADP-ribosylation factor or phosphatidylinositiol 4,5-bisphosphate to digitonin-permeabilized cells did not augment PLD activity. In intact cells PLD activity was increased by sodium oleate but there was no significant change between dexamethasone treated- and untreated cells by oleate. These results suggest that at least two types of PLD are present in M-1 cells and PLD plays a role in the corticosteroid-mediated response of cortical collecting duct cells.

The C677T mutation in the methylene tetrahydrofolate reductase gene increases serum uric acid in elderly men

A common mutation, C677T, in the methylene tetrahydrofolate reductase gene (MTHFR) reduces the activity of MTHFR and increases total homocysteine levels in plasma. Increased homocysteine levels are reportedly associated with high serum uric acid levels. The relationship between the MTHFR mutation and uric acid metabolism remains unclear, however. To investigate whether the C677T MTHFR mutation is a risk factor for hyperuricemia, we performed MTHFR genotyping and clinical laboratory determinations, including serum uric acid, in 271 elderly Japanese men (age range, 40-79 years; mean, 52.6 years). The mean uric acid levels for the C/C, C/T, and T/T genotypes were 5.67, 6.00, and 6.39 mg/dl, respectively (P = 0.012). The T/T genotype was more frequent in subjects with high uric acid levels than in those with low uric acid levels (P = 0.038). These findings suggest that the C677T MTHFR mutation contributed to higher uric acid levels in subjects enrolled in this study. In conclusion, the mutation of the MTHFR gene may be a risk factor for hyperuricemia in elderly men.

Pediatric eosinophilic gastroenteritis: report of one case

Eosinophilic gastroenteritis is an uncommon disease of unknown cause found particularly in children. It is characterized by the infiltration of eosinophils into the wall of the gastrointestinal tract, peripheral eosinophilia, and chronic relapsing gastrointestinal disorder. This report describes a patient with serosal eosinophilic gastroenteritis presenting ascites and peripheral eosinophilia. The diagnosis of the eosinophilic gastroenteritis was supported by sonographic analysis and dramatic clinical response to prednisolone therapy.

Transfusion-dependent congenital dyserythropoietic anaemia with intraerythroblastic inclusions of a non-globin protein

The congenital forms of dyserythropoiesis comprise a group of hereditary disorders characterized by ineffective erythropoiesis as the predominant mechanism of anaemia and morphologically abnormal erythroblasts. Up to now three major forms and four variants have been described. Group VII is characterized by dyserythropoiesis with intraerythroblastic precipitation of a non-globin protein. Here we described a case of dyserythropoietic anaemia presenting neonatally and requiring regular blood transfusions. Optical and electronic microscopy studies confirmed that this case was very similar to those in two previously reported transfusion-dependent patients with an unusual type of congenital dyserythropoietic anaemia.

Molecular genetic analysis and mutation screening of the VHL gene in a Japanese family with von Hippel-Lindau disease

Von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited familial cancer syndrome which predisposes individuals to a variety of malignant and benign tumors. Its penetrance is almost 100% by 61-70 years of age. We have identified a germline mutation in the VHL gene of a Japanese male patient with a retinal hemangioma in the left eye, an intracranial hemangioblastoma, a left renal tumor and bilateral pheochromocytomas. Screening for the mutation was performed in all members of the patient's family at risk for VHL disease. The mutation identified in the patient was a missense mutation at codon 238 (CGG to CAG). The elder daughter, who did not show any clinical symptoms, was found to carry the same mutation. In order to detect and treat tumors in VHL patients at an earlier stage, it is necessary to identify and screen for the VHL gene mutation in all family members known at risk.

Effects of various implant materials on regeneration of calvarial defects in rats

The purpose of the present study was to determine the best implant material, the best conditions to substitute absorbable membrane for non-absorbable membrane, and the factors influencing guided regeneration of critical size defects using experimental rats. An 8-mm circular transosseous calvarial bony defect was made and implant materials, such as demineralized freeze-dried bone (DFDB), absorbable membrane (BioMesh; Samyang Co., Seoul Korea), non-absorbable membrane (Millipore filter; Micro Filtration System, MA, USA) or a combination of these materials, was placed on the defect. As for the results of sequential time-based guided bone regeneration, histological, histochemical, immunohistochemical and histomorphometric aspects were observed, and a statistical comparative analysis was performed, with control group of a soft tissue flap. Bone formation was significantly enhanced when DFDB was retained within the defect with a protective absorbable membrane. Inframembranous DFDB-filling was required to prevent membrane collapse and to preserve spaces for bone regeneration. The absorbable membrane which was recommended to overcome the disadvantages of the non-absorbable membrane should remain intact for more than 5 weeks in order for it to be effective. The macrophages recruited by grafts were involved partly in decreasing bone regeneration via the sequential events of releasing fibronectin, and in chemotactic effect of the fibronectin to fibroblasts and collagen lay-down. Thus, the activity of new bone formation was dependent upon the physical barrier effect of the membrane, such as the preserving ability to secure spaces and the suppression ability of early infiltration of collagen and epithelium, inducible ability of inflammation by the implant material, and potential in guiding bone regeneration of the grafts.

Anesthesia practice and clinical trends in interventional radiology: a European survey

PURPOSE

To determine current European practice in interventional radiology regarding nursing care, anesthesia, and clinical care trends.

METHODS

A survey was sent to 977 European interventional radiologists to assess the use of sedoanalgesia, nursing care, monitoring equipment, pre- and postprocedural care, and clinical trends in interventional radiology. Patterns of sedoanalgesia were recorded for both vascular and visceral interventional procedures. Responders rated their preferred level of sedoanalgesia for each procedure as follows: (a) awake/alert, (b) drowsy/arousable, (c) asleep/arousable, (d) deep sedation, and (e) general anesthesia. Sedoanalgesic drugs and patient care trends were also recorded. A comparison was performed with data derived from a similar survey of interventional practice in the United States.

RESULTS

Two hundred and forty-three of 977 radiologists responded (25%). The total number of procedures analyzed was 210,194. The majority (56%) of diagnostic and therapeutic vascular procedures were performed at the awake/alert level of sedation, 32% were performed at the drowsy/arousable level, and 12% at deeper levels of sedation. The majority of visceral interventional procedures were performed at the drowsy/arousable level of sedation (41%), 29% were performed at deeper levels of sedation, and 30% at the awake/alert level. In general, more sedoanalgesia is used in the United States. Eighty-three percent of respondents reported the use of a full-time radiology nurse, 67% used routine blood pressure/pulse oximetry monitoring, and 46% reported the presence of a dedicated recovery area. Forty-nine percent reported daily patient rounds, 30% had inpatient hospital beds, and 51% had day case beds.

CONCLUSION

This survey shows clear differences in the use of sedation for vascular and visceral interventional procedures. Many, often complex, procedures are performed at the awake/alert level of sedation in Europe, whereas deeper levels of sedation are used in the United States. Trends toward making interventional radiology a clinical specialty are evident, with 51% of respondents having day case beds, and 30% having inpatient beds.

Percutaneous gastrostomy in patients who fail or are unsuitable for endoscopic gastrostomy

PURPOSE

Percutaneous endoscopic gastrostomy (PEG) is not possible or fails in some patients. We aimed to categorize the reasons for PEG failure, to study the success of percutaneous radiologic gastrostomy (PRG) in these patients, and to highlight the associated technical difficulties and complications.

METHODS

Forty-two patients (28 men, 14 women; mean age 60 years, range 18-93 years) in whom PEG failed or was not possible, underwent PRG. PEG failure or unsuitability was due to upper gastrointestinal tract obstruction or other pathology precluding PEG in 15 of the 42 patients, suboptimal transillumination in 22 of 42 patients, and advanced cardiorespiratory decompensation precluding endoscopy in five of 42 patients. T-fastener gastropexy was used in all patients and 14-18 Fr catheters were inserted.

RESULTS

PRG was successful in 41 of 42 patients (98%). CT guidance was required in four patients with altered upper gastrointestinal anatomy. PRG failed in one patient despite CT guidance. In the 16 patients with high subcostal stomachs who failed PEG because of inadequate transillumination, intercostal tube placement was required in three and cephalad angulation under the costal margin in six patients. Major complications included inadvertent placement of the tube in the peritoneal cavity. There was one case of hemorrhage at the gastrostomy site requiring transfusion and one case of superficial gastrostomy site infection requiring tube removal. Minor complications included superficial wound infection in six patients, successfully treated with routine wound toilette.

CONCLUSION

We conclude that PRG is a safe, well-tolerated and successful method of gastrostomy and gastrojejunostomy insertion in the technically difficult group of patients who have undergone an unsuccessful PEG. In many such cases optimal clinical evaluation will suggest primary referral for PRG as the preferred option.

Cadmium blocks hypoxia-inducible factor (HIF)-1-mediated response to hypoxia by stimulating the proteasome-dependent degradation of HIF-1alpha

Cadmium is a substantial industrial and environmental pollutant which seriously impairs erythropoiesis. Cd has been demonstrated to aggravate anemia by suppressing erythropoietin gene expression in anemic patients. As hypoxic induction of erythropoietin mRNA depends on a transcription factor, hypoxia-inducible factor 1 (HIF-1), we hypothesized that Cd suppresses the hypoxic activation of HIF-1. In hypoxic Hep3B cells, all mRNAs of various genes, which are known to be upregulated by HIF-1 activation under hypoxia, were suppressed by Cd in a dose-dependent manner. Cd inhibited the hypoxia-induced activity of luciferase in 293 cells which was transfected with a reporter plasmid carrying a hypoxia response element. By electrophoretic mobility gel shift assay, Cd inhibited the DNA-binding activity of HIF-1 in hypoxic Hep3B cells. Cd reduced the amount of HIF-1alpha protein in hypoxia, whereas it didn't affect HIF-1 alpha mRNA levels. Moreover, Cd inhibited HIF-1alpha accumulation induced by cobalt and desferrioxamine. Antioxidants and a proteasome inhibitor prevented the HIF-1alpha degradation caused by Cd. The possibility that oxidative stress mediates this action of Cd was examined. Cd didn't affect protein oxidation and reduced glutathione levels in hypoxic cells. These results indicate that Cd triggers a redox/proteasome-dependent degradation of HIF-1alpha protein, reducing HIF-1 activity and in turn suppressing the hypoxic induction of hypoxia-inducible genes.

Specificity of detection of Chlamydia pneumoniae in cardiovascular atheroma

Chlamydia pneumoniae is commonly detected in atherosclerotic plaque but the frequency of detection in non-cardiovascular (CV) tissues has not been well determined. In this study, archival autopsy tissue specimens from both CV and non-CV sites from 38 patients were tested by polymerase chain reaction and immunocytochemistry to detect C. pneumoniae. In addition, 33 surgical granuloma biopsy specimens were also tested. C. pneumoniae was detected most frequently in coronary artery tissue (34%) but was also detected in specimens from lung (13%), liver (10%), spleen (5%), bone marrow (10%), and lymph node (8%). The organism was detected in 3 of 33 granuloma specimens. These findings suggest that C. pneumoniae demonstrates a tropism for CV tissues and is either not widely distributed to non-CV tissues or does not persist chronically in those tissues after initial infection.

Interventional radiologic procedures: patient anxiety, perception of pain, understanding of procedure, and satisfaction with medication--a prospective study

PURPOSE

To prospectively assess patient anxiety, understanding of the procedure being performed, perception of pain level, and satisfaction with medication given for a variety of diagnostic and therapeutic vascular and visceral (nonvascular) interventional procedures.

MATERIALS AND METHODS

The authors interviewed 204 patients before and after they underwent an interventional radiologic procedure. Patients responded to a series of questions by using a visual analog scale. Patients were grouped according to (a) their level of experience with the procedure and (b) the type of procedure performed (diagnostic or therapeutic visceral procedure or diagnostic or therapeutic vascular procedure).

RESULTS

Patients who had previous experience with a procedure, whether visceral or vascular, were less anxious, had more understanding, and anticipated less pain than did those who did not have experience with a procedure. Patients who had only local anesthesia for visceral biopsy experienced greater pain than did those who had both local and intravenous anesthesia. Satisfaction scores, however, were similar throughout all groups.

CONCLUSION

Patients have a moderate amount of anxiety about interventional procedures and anticipate some discomfort. Most patients have a high level of satisfaction despite the amount of pain they experience during the procedure. Patients experienced with a procedure tend to have a greater understanding of the procedure and less anxiety.

Treatment of hostile midline back wounds: an extreme approach

The basic principles of successful wound closure remain the same: careful preoperative evaluation, removal of underlying nonviable tissue, and well-vascularized soft-tissue coverage. Many complex or "hostile" back wound closures also require stabilization of the spine and a two-layered wound closure. The use of long arteriovenous fistulas with free tissue transfer provides an additional weapon for the treatment of these complex wounds.

Metal artifact reduction sequence: early clinical applications

Artifact arising from metal hardware remains a significant problem in orthopedic magnetic resonance imaging. The metal artifact reduction sequence (MARS) reduces the size and intensity of susceptibility artifacts from magnetic field distortion. The sequence, which is based on view angle tilting in combination with increased gradient strength, can be conveniently used in conjunction with any spin-echo sequence and requires no additional imaging time. In patients with persistent pain after femoral neck fracture, the MARS technique allows visualization of marrow adjacent to hip screws, thus enabling diagnosis or exclusion of avascular necrosis. Other applications in the hip include assessment of periprosthetic soft tissues after hip joint replacement surgery, postoperative assessment after resection of bone tumors and reconstruction, and localization of unopacified methyl methacrylate cement prior to hip arthroplasty revision surgery. In the knee, the MARS technique allows visualization of structures adjacent to implanted metal staples, pins, or screws. The technique can significantly improve visualization of periprosthetic bone and soft-tissue structures even in patients who have undergone total knee arthroplasty. In patients with spinal fixation hardware, the MARS technique frequently allows visualization of the vertebral bodies and spinal canal contents. The technique can be helpful after wrist fusion or screw fixation of scaphoid fractures.

Synthesis of 5-(4-alkoxy-[1,2,5]thiadiazol-3-yl)-3-methyl-1,2,3,4-tetrahydropyrimidi ne oxalate salts and their evaluation as muscarinic receptor agonists

The synthesis and biological testing of 5-(4-alkoxy-[1,2,5]thiadiazol-3-yl)-3-methyl-1,2,3,4-tetrahydro pyrimidine oxalate salts 8 as muscarinic receptor agonists are described. The key intermediate 4 was obtained by modified Strecker reaction and cyclization of starting material 1. Subsequent alkoxy substitution, quaternization, and reduction afforded 7. For the sake of purity and stability of the final products 8, the 3-methyl-1,2,3,4-tetrahydropyrimidines were obtained as oxalic acid salts. All final compounds were examined in vitro for their binding affinities to the cloned human muscarinic receptor by the [3H]-NMS binding assay.

Mecamylamine prevents tolerance but enhances whole brain [3H]epibatidine binding in response to repeated nicotine administration in rats

RATIONALE

Chronic administration of nicotine in rats results in upregulation of neuronal nicotinic receptors. Upregulation has been proposed to reflect receptor desensitization, which may underlie functional tolerance to nicotine's effects. However, evidence indicates that tolerance and upregulation do not always parallel each other, suggesting that either upregulation does not always reflect desensitization, or mechanisms other than receptor desensitization account for tolerance to nicotine.

OBJECTIVES

The present studies examined tolerance to nicotine-induced antinociception and changes in receptor binding after two regimens of intermittent nicotine injections in rats. The role of receptor activation in upregulation and tolerance was also examined by co-administering nicotine with the non-competitive antagonist, mecamylamine.

METHODS

Sprague-Dawley rats were administered a short (once-daily, s.c. for 6 days (0.35 mg/kg)) or long (twice-daily for 11 days (0.66 mg/kg)) series of injections and tolerance to nicotine-induced antinociception and [3H]epibatidine binding in whole brain were measured.

RESULTS

The short series of injections resulted in tolerance to nicotine-induced antinociception, but failed to increase [3H]epibatidine binding. In contrast, the long series of injections resulted in both tolerance and increased receptor binding. Once-daily pairings of mecamylamine (1 mg/kg, s.c.) with nicotine (0.35 mg/kg) for 6 days blocked the development of tolerance, indicating receptor activation is necessary for tolerance to occur. Pairing mecamylamine with nicotine (0.66 mg/kg) twice daily for 11 days blocked tolerance but produced a greater increase in [3H]epibatidine binding than nicotine alone.

CONCLUSIONS

A dissociation of tolerance from receptor upregulation was observed in the present study. The finding that receptor activation may be necessary for tolerance but not upregulation is discussed within the context of possible mechanisms controlling tolerance to nicotine.

Expression of cyclin D1, cyclin E, cdk4 and loss of heterozygosity of 8p, 13q, 17p in hepatocellular carcinoma: comparison study of childhood and adult hepatocellular carcinoma

AIMS/BACKGROUND

In hepatitis B virus-related hepatocellular carcinoma (HCC), at least 20-40 years of continuous necro-inflammation is necessary for the hepato-carcinogenesis to occur. However, HCC in childhood shows an unusually short latent period and rapid progression. In our previous report, mutation of c-met was found only in childhood HCC, but not in adult HCC. In order to determine the specific biological tumorous features of childhood HCC, a comparison study of childhood and adult HCC was performed.

METHODS

Eighteen cases of HBV positive HCC (nine children and nine adults aged more than 40 years) were selected. The expression of G1 phase regulatory proteins (cyclin D1, cyclin E and cdk4) was studied using immunohistochemical methods. Loss of heterozygosity (LOH) on chromosomal arms 8p, 13q and 17p was analyzed.

RESULTS

Cyclin D1 expression was significantly lower in childhood HCC than in adult HCC (cases of cyclin D1 expression under 3+: childhood 5/9 vs. adult 1/9, p=0.046). No difference in cyclin E and cdk4 expression was found between childhood and adult HCC. LOH frequency on 13q was relatively higher in childhood than in adult HCC (66.7% vs. 22.2%, p=0.058). LOH frequency on 8p and 17p was 44.4% and 33.3% in childhood HCC and 44.4% and 75% in adult HCC with no statistical significance between the two groups.

CONCLUSION

Our data suggest that childhood HCC may be less dependent on cyclin D1 protein for tumor growth and progression than adult HCC, and that the LOH on 13q may be an important feature of childhood HCC.

Adult T cell leukemia/lymphoma with lymphopenia in a Korean

We experienced a case of adult T cell leukemia/lymphoma (ATLL) in a 48-year-old Korean female, who has never been abroad since birth and no history of blood transfusion. The patient had hypercalcemia and multiple lymphadenopathy. Histopathologic study of left cervical lymph node (LN) and bone marrow (BM) revealed that infiltrates of malignant lymphoid cells were composed of small, medium and large cells with pleomorphic nuclei. Smears of peripheral blood (PB) showed lymphopenia (16%) with the appearance of a few atypical lymphoid cells (less than 2%), but not the typical clover leaf cells seen in ATLL. Immunophenotypic study of LN and BM revealed T cell phenotype. PB showed increased CD4+ T cell (T(H), CD3/CD4+, 57%) and decreased CD8+ T cell counts (T(S), CD3/CD8+, 6.7%). The sera of the patient and her family were reactive for HTLV-I antibody. The specific sequences of pol, env, and tax of HTLV-I DNA were detected in the lymphoma cells and peripheral blood mononuclear cells (PBMC) using polymerase chain reaction. Ultrastructural examination of PBMC confirmed numerous type c virus particles in extracellular space. This case was an acute type of ATLL without overt leukemic features in PB. Despite chemotherapy and intensive conservative treatment, she died 3 months after admission.

Sphingosine-1-phosphate signaling via the EDG-1 family of G-protein-coupled receptors

The bioactive lipid sphingosine-1-phosphate (SPP) is abundantly formed and released during the activation of platelets by thrombotic stimuli. Once exported, SPP interacts with the G-protein-coupled receptors (GPCR) of the EDG-1 family. SPP binds to EDG-1 with the dissociation constant of approximately 8 nM and induces signal transduction events such as mitogen-activated protein kinase (MAP kinase) activation, decrease of cAMP levels, remodeling of the actin cytoskeleton, among others. EDG-1 is a prototypical member of a large family of GPCRs that interact with glycero- and sphingolysolipid phosphates, namely, SPP and lysophosphatidic acid (LPA). Three other GPCRs, trivially termed EDG-3, EDG-5, and EDG-8, are also high-affinity receptors for SPP. The four SPP receptor subtypes regulate different intracellular signal transduction pathways. In vascular endothelial cells, cooperative signaling between EDG-1 and EDG-3 subtypes of SPP receptors results in adherens junction assembly, cell survival, morphogenesis into capillary-like networks, and angiogenesis. SPP acts distinctly, albeit cooperatively, with polypeptide angiogenic factors, resulting in the formation of mature neovessels. Thus SPP signaling as an extracellular mediator via the EDG-1 family of GPCRs may be a heretofore unrecognized mechanism for the regulation of angiogenesis and vascular endothelial cell function.

Prevalence and significance of gallbladder abnormalities seen on sonography in intensive care unit patients

OBJECTIVE

We evaluated sonographic abnormalities of the gallbladder other than acalculous cholecystitis across a broad range of intensive care unit (ICU) patients.

SUBJECTS AND METHODS

Fifty-five consecutive patients (age range, 18-94 years old; mean age, 56 years; 33 men, 22 women), who were admitted to the ICU with a variety of diagnoses, underwent sonography of the gallbladder twice a week. Patients with gallbladder calculi were excluded from the study. The gallbladder was examined for the recognized sonographic features of acalculous cholecystitis: gallbladder wall thickening, gallbladder distention, intramural gallbladder lucencies (striated gallbladder wall), pericholecystic fluid, gallbladder sludge, and Murphy's sign. These findings were correlated with clinical and laboratory parameters that are associated with acalculous cholecystitis: fever, WBC, liver function tests, levels of serum bilirubin, mechanical ventilation status, and administration of parenteral nutrition, narcotic analgesics, antibiotics, and pressor agents.

RESULTS

Eleven of the 55 patients were found to have gallbladder calculi and were excluded from the study. Thirty-seven (84%) of the remaining 44 patients had at least one sonographic abnormality while in the ICU. Twenty-five (57%) of the 44 patients had as many as three abnormalities found on sonography, and six (14%) of 44 patients had four or five sonographic findings of gallbladder abnormalities while in the ICU. No statistically significant correlation was found among any of these sonographic abnormalities and the clinical and laboratory parameters.

CONCLUSION

Gallbladder abnormalities are frequently seen on sonography in ICU patients, even if these patients are not suspected of having acalculous cholecystitis; therefore, sonography appears to be of limited value in diagnosing acalculous cholecystitis in ICU patients.

A tetrodotoxin-producing Vibrio strain, LM-1, from the puffer fish Fugu vermicularis radiatus

Identification of tetrodotoxin (TTX) and its derivatives produced from a Vibrio strain in the intestine of the puffer fish Fugu vermicularis radiatus was performed by thin-layer chromatography, electrophoresis, high-performance liquid chromatography, and gas chromatography-mass spectrometry, together with a mouse bioassay for toxicity. It was demonstrated that the isolated bacterium produced TTX, 4-epi-TTX, and anhTTX during cultivation, suggesting that Vibrio strains are responsible for the toxification of the puffer fish.