Hepatic extraction fraction of hepatobiliary radiopharmaceuticals measured using spectral analysis

Measuring the hepatic extraction fraction (HEF) of a hepatobiliary radiopharmaceutical helps to differentiate hepatocyte from biliary tract diseases, and it is generally performed using deconvolution analysis. In this study, we measured HEF using spectral analysis. With spectral analysis, HEF was calculated from (the sum of the spectral data obtained by spectral analysis--the highest frequency component of the spectrum) divided by (the sum of the spectral data) x 100 (%). We applied this method to dynamic liver scintigraphic data obtained from six healthy volunteers and from 46 patients with various liver diseases, using 99Tcm-N-pyridoxyl-5-methyltryptophan (PMT). We also measured HEF using deconvolution analysis, in which the modified Fourier transform technique was employed. The HEF values obtained by spectral analysis correlated closely with those obtained by deconvolution analysis (r = 0.925), suggesting our method is valid. The HEF values obtained by spectral analysis decreased as the severity of liver disease progressed. The values were 100.0 +/- 0.0%, 94.7 +/- 13.6%, 76.2 +/- 27.4%, 45.7 +/- 15.6%, 82.7 +/- 24.2% and 95.2 +/- 11.8% (mean +/- S.D.) for the normal controls (n = 6), mild liver cirrhosis (n = 16), moderate liver cirrhosis (n = 11), severe liver cirrhosis (n = 5), acute hepatitis (n = 8) and chronic hepatitis groups (n = 6), respectively. The HEF was obtained more simply and rapidly by spectral analysis than by deconvolution analysis. The results suggest that our method using spectral analysis can be used as an alternative to the conventional procedure using deconvolution analysis for measuring HEF.     

Clinicopathological study of intrapelvic cancer spread to the iliac area in lower rectal adenocarcinoma by serial sectioning

BACKGROUND: The role of iliac lymphadenectomy in surgery for rectal cancer remains unknown. Detailed clinicopathological data on lateral cancer extension may be needed to determine the true role of this procedure. METHODS: Seventy consecutive patients with low rectal cancer who underwent systematic iliac lymphadenectomy between 1991 and 1995 were reviewed. The iliac area was divided into five regions: (1) middle rectal root, (2) internal iliac, (3) obturator, (4) common iliac and (5) external iliac. Iliac lymph nodes that were cancer-free based on conventional pathological examination were serially sectioned at 100-microm intervals and re-examined for occult microscopic involvement. RESULTS: Occult microscopic foci were detected in five (7 per cent) of the 70 patients, and the overall incidence of lateral cancer spread was 24 per cent (17 of 70). Among patients without other sites of distant metastasis or circumferential involvement of the margin, the 5-year survival rate of those with lateral spread was 35 per cent. Although the prognosis of patients with cancer involving multiple iliac regions was poor, three of six patients with metastasis to only a single region were alive without disease at 3 years. CONCLUSION: Surgeons should be aware of the possibility of localized lateral spread, including microscopic metastasis, when determining the optimum procedure for iliac lymphadenectomy in patients with rectal cancer.     

A case of pelvic aggressive angiomyxoma involving urinary bladder

A 23-year-old man visited hospital with the complaints of hematuria and miction pain. Computed tomography and magnetic resonance imaging of the pelvis showed a large pelvic tumor contiguous to the urinary bladder. Resection of the tumor with partial cystectomy was performed on February, 1998. Histopathological examination showed that the tumor composed of angiomyxoma infiltrating into the urinary bladder. The patient is alive without recurrence of aggressive angiomyxoma 12 months after surgery. To our knowledge, this is the first report in the Japanese literature of aggressive angiomyxoma involving the urinary bladder. Awareness of this uncommon neoplasma is important in the diagnosis of pelvic tumor to prevent an extensive surgery.     

Usefulness of magnetic resonance imaging of the wrist for the early diagnosis of dialysis-related amyloidosis

Dialysis-related amyloidosis (DRA) is a major complication of long-term hemodialysis patients. The onset of arthropathy is frequently preceded by carpal tunnel syndrome, but the early non-invasive diagnosis of DRA remains unclear. beta 2-microglobulin amyloid deposits in joint synovia and soft tissue precede radiological abnormalities. Magnetic resonance imaging (MRI) may play a more important role in the early diagnosis of DRA, because it allows direct visualization of synovitis and deposition of abnormal soft tissue. The purpose of this study was to evaluate the usefulness of MRI of the wrist for the early diagnosis of DRA. The study included 72 patients (male 37, female 35) undergoing hemodialysis from initiation to 20 years. The patients were examined by MR images of synovitis, deposition of abnormal soft tissue and cystic bone lesions at the wrists. Normal MR images of synovia and soft tissue were defined in 6 control subjects (2 normal 4 non-dialysis patients). Synovitis of the carpal bones was found in 23% of the patients at the start of hemodialysis. Deposition of abnormal soft tissue in the carpal canal and cystic bone lesions were detected after 1 and 2 years of hemodialysis, respectively. All findings were increased significantly with an increasing duration of dialysis. Synovitis was present in 90% of the patients with deposition of abnormal soft tissue, and in 80% of the patients with cystic bone lesions. beta 2-microglobulin value was significantly higher in patients with synovitis, deposition of abnormal soft tissue and cystic bone lesions than in patients without these findings. Our experience suggest that synovitis examined by MRI of the wrists is useful for the early diagnosis of DRA. Thereby, intensive follow-up and management of DRA are required in patients with synovitis at the start of hemodialysis.     

Morphology and barrier function of the corneal epithelium after penetrating keratoplasty: association with original diseases, tear function, and suture removal.

PURPOSE: To study changes in structure and barrier function of the corneal epithelium after penetrating keratoplasty. METHODS: Sixty-nine eyes of 56 patients undergoing penetrating keratoplasty were studied. Fifty-six age-matched normal eyes served as controls. Corneal epithelial structure was studied by using specular microscopy. Barrier function of the corneal epithelium was examined by slit-lamp fluorophotometry. Vital staining, tear function, and corneal sensitivity also were examined. RESULTS: Fluorescein and rose bengal staining scores, incidence of elongated cells, the mean epithelial area, and mean fluorescein uptake were significantly increased in postkeratoplasty eyes compared with controls. Original disease influenced the results of barrier function, where keratoconus revealed better function than bullous keratopathy or corneal scar. However, no such differences were noted in epithelial structure. Six eyes with absence of palisades of Vogt had revealed significantly increased epithelial area and fluorescein uptake. Removal of the running suture caused a decrease in elongated cells and epithelial cell area without significant changes in barrier function. CONCLUSION: Corneal epithelial structure was significantly impaired in postkeratoplasty eyes. Epithelial barrier function of postkeratoplasty eyes was influenced by original diseases. Removal of sutures improves epithelial structure but not barrier function.     

In vivo release of neuronal histamine in the hypothalamus of rats measured by microdialysis

Summary Using an in vivo intracerebral microdialysis method coupled with an HPLC-fluorometric method, we investigated the extracellular level of endogenous histamine in the anterior hypothalamic area of urethaneanaesthetized rats. The basal rate of release of endogenous histamine in the anterior hypothalamic area measured by this method was 0.09 + 0.01 pmol/20 min. When the anterior hypothalamic area was depolarized by infusion of 100 mM K⁺ through the dialysis membrane or electrical stimulation at 200 A was applied through an electrode implanted into the ipsilateral tuberomammillary nucleus, histamine release increased to 175% and 188%, respectively, of the basal level. These increases were completely suppressed by removal of extracellular Ca²⁺. The basal release of histamine was also suppressed after infusion of 10^–6 M tetrodotoxin or i.p. administration of 100 mg/kg of -fluoromethylhistidine. On the other hand, 3-fold increase in the basal release was observed after i. p. administration of 5 mg/kg thioperamide. These results clearly indicate that both the basal and evoked release of histamine measured by our method are of neuronal origin. Send offprint requests to T. Mochizuki at the above address     

Cytokine production in surgical stress

Surgical injury influences the function of mononuclear cells, leading to various systemic responses. Proinflammatory cytokines such as tumor necrosis factor alpha (TNF alpha), interleukin (IL)-1, -6, -8, and the antiinflammatory cytokine IL-10, which are mainly produced by mononuclear cells, are known to play an important role in the response to and pathogenesis of surgical stress. TNF alpha production by monocytes is extremely upregulated, but monocyte HLA-DR antigen expression is suppressed in patients with surgical stress. While production of Th1 cytokines such as IL-12 and interferon-gamma by mononuclear cells is suppressed, production of Th2 cytokines and IL-10 is upregulated during surgical stress. Immune suppression following surgical stress has been clarified recently in terms of Th1 and Th2 cytokine production balance mainly caused by mononuclear cells. It is thought to be very important to maintain immunological function after surgical stress by controlling cytokine production and balance.