Gametocytogenesis of Leucocytozoon caulleryi in in vitro culture: effect of human red blood cells on the development of second-generation merozoites

For investigating development of second-generation merozoites of Leucocytozoon caulleryi into mature gametocytes, infected erythrocytes from chickens at 15 d after sporozoites inoculation were cultured in RPMI-1640 modified medium supplemented with 10% horse serum and 0.5 ml of human erythrocytes (type O). When culture was carried out at 37 degrees C in a humidified atmosphere or 5% CO2 for 7 d, the very small number of second-generation merozoites developed into morphologically mature gametocytes. However, in the high carbon dioxide and low oxygen condition, mature gametocytes weren't observed in culture. The role of human erythrocytes added has not been clarified yet.

Detection of Bacteroides fragilis by PCR assay targeting the neuraminidase-encoding gene

Oligonucleotide primers were designed on the basis of the sequence of the neuraminidase-encoding gene (nanH) of Bacteroides fragilis and used for the specific detection of this anaerobe by the nested PCR assay. Fifty-nine of 60 representative strains of Bact. fragilis were detected, while none of 45 strains of other species generated visible PCR products. The detection limits of Bact. fragilis cells and DNA by the nested PCR were 10 colony-forming units and 10 fg of chromosomal DNA, respectively. The PCR assay targeting the nanH gene has the potential for the detection of Bact. fragilis.

In vitro-in vivo correlation in anticancer drug sensitivity test using AUC-based concentrations and collagen gel droplet-embedded culture

To improve the ability of an in vitro drug sensitivity test to predict in vivo effects, we applied a drug concentration that was pharmacokinetically equivalent to plasma levels and collagen gel droplet-embedded culture with a high cloning efficiency. We reported that the cell-killing effect of cell cycle phase-nonspecific drugs such as mitomycin C, cisplatin and Adriamycin depends on the area under the drug concentration-time curve (AUC). The plasma AUC values of these drugs were estimated after an injection into nude mice at the maximal tolerated doses (MTD). Tumor cells isolated from human tumor xenografts implanted into nude mice and cultured in collagen gel droplets were exposed to drugs under conditions that can reproduce the plasma AUC in vitro. The in vitro sensitivity to a drug was compared with the in vivo response of the same tumor treated with the MTD of the drug. When the criterion of sensitivity was taken as 50% or less of the growth inhibition (growth rate of treated group/that of control group, T/C), the correlation between the in vitro and in vivo growth inhibition of all 3 drugs tested was relatively high (86% of the true-positive rate, 82% of the true-negative rate and 83% of the correlation rate).

Immunolocalization of prolyl 4-hydroxylase in fibroblasts cultured from Tenon's capsule of humans

BACKGROUND

The excessive accumulation of extracellular matrix (ECM) with the repopulation of fibroblasts may lead to an unsuccessful outcome of glaucoma filtering surgery. We examined the immunolocalization of ECM components and prolyl 4-hydroxylase, an enzyme involved in collagen biosynthesis, in cultured Tenon's capsule fibroblasts (TCFs) of humans to evaluate the production of ECM in the cells.

METHODS

We used light microscopy to evaluate the immunolocalization of prolyl 4-hydroxylase and ECM components, collagen types I, III, and IV, cellular fibronectin, and laminin in TCFs. Ultrastructural localization of the enzyme was also evaluated by electron microscopy.

RESULTS

Immunoreactivity with monoclonal antibodies against the alpha and beta subunits of the enzyme or with the polyclonal antibody against it was detected in the cytoplasm of the cells in a fine granular pattern, indicating its localization in the endoplasmic reticulum (ER). Immunoreactivity for the enzyme was detected in the cisternae of the ER on electron microscopy. Types I and III collagen reactivities were also observed in the cytoplasm in a fine granular pattern. Type IV collagen reactivity was present diffusely on the cell surface. The distribution of laminin reactivity in the cytoplasm resembled that of types I and III collagen. Cellular fibronectin reactivity was observed in the ECM in a reticular pattern.

CONCLUSION

Prolyl 4-hydroxylase was located in the cisternae of the ER. TCFs produced a variety of ECM components in vitro. The results provide insight into the fibrotic process during scar formation at the site of a bleb following filtering surgery.

Histologic findings and prognosis of uveal malignant melanoma in japanese patients

PURPOSE

To determine factors of uveal malignant melanoma that would help to predict prognosis in Japanese patients.

METHODS

From 1969 to 1994, 23 eyes with uveal malignant melanoma were enucleated from 23 Japanese patients, and 16 of these patients were studied. In the 16 patients, enucleated eyes were evaluated for tumor characteristics, including cell type and microvascular architecture. Patient records were reviewed for follow-up therapy and outcome. Mortality rate was evaluated four years after enucleation.

RESULTS

In Japanese patients with uveal malignant melanoma, the average tumor size was larger (average largest diameter, 11.36 mm; average increase, 6.25 mm) and the average patient age was younger (55.2 years old) than previously reported for white populations. Patients with spindle cell type melanoma tended to have a better prognosis than those with epithelioid cell type (four-year mortality rates: spindle cell type, 0%; mixed cell type, 43%; epithelioid cell type, 66%). Microvascular architecture patterns interpreted as either network or closed loop patterns were associated with a poorer prognosis (network pattern, P = .03; closed loop pattern, P = .005).

CONCLUSIONS

The prognosis for Japanese patients with uveal malignant melanoma is poorer, and epithelioid cell-type melanoma is more common, than has been reported in white populations. Mitotic figures are well correlated with poor prognosis, as are two microvascular patterns, the network pattern and the closed loop pattern.

Advantage of in vivo chemosensitivity assay to detect vincristine-resistance in a human epidermoid carcinoma xenograft

We examined both in vitro and in vivo chemosensitivity of the human epidermoid carcinoma xenograft xeKB3-1-R which shows overexpression of the multidrug resistance gene (MDR1). XeKB3-1-R was sensitive to vincristine (VCR, 6%) and doxorubicin (DOX, 9%) in the adhesive tumor cell culture system in vitro. However, this xenograft showed decreased sensitivity to VCR (65%) and DOX (42%) in an in vivo chemosensitivity assay. The in vivo resistance of xeKB3-1-R to both VCR and DOX was reversed by coadministration of cyclosporin A (VCR 22%, DOX 11%). The xenograft xeKB3-1-R expressed significantly higher levels of MDR1 than xeKB3-1. The results confirmed that multidrug resistance in xeKB3-1-R was related to enhanced MDR1 expression in vivo. The observed discrepancies between in vitro and in vivo chemosensitivities suggest that the in vivo sensitivity assay more accurately reflects drug resistance as a result of low-level MDR1 overexpression in solid tumors.

[Comparison of cerebral oxygen metabolism during normothermic versus moderate hypothermic cardiopulmonary bypass]

We compared the effects of normothermic (NCPB, N = 5) and moderate hypothermic (HCPB, (N = 5) cardiopulmonary bypass on cerebral oxygen metabolism in patients undergoing coronary artery bypass grafting. For monitoring of cerebral oxygenation, we used jugular venous oxyhemoglobin saturation (SjVO2) and near infrared spectroscopy (NIR). In NCPB group, although SjVO2 decreased temporally at the start of cardiopulmonary bypass, it became stabilized above 50% during the rest of cardiopulmonary bypass. In HCPB group, on the contrary, oxyhemoglobin measured by NIR showed maximum decrease during rewarming under cardiopulmonary bypass. Furthermore, SjVO2 decreased under 50% at the end of cardiopulmonary bypass (3/5 cases). We consider that NCPB is a useful technique for preventing cerebral hypoxia, if the decrease of SjVO2 during the early period of cardiopulmonary bypass is avoidable. Lastly, we also advocate that both SjVO2 and NIR are useful monitoring systems for continuous evaluation of cerebral oxygen metabolism during cardiopulmonary bypass.

[Anesthetic management for AICD (automatic implantable cardioverter defibrillator) implant surgery]

We studied anesthetic management and monitoring during AICD (automatic implantable cardioverter defibrillator) implantation. For anesthetic management, complete sedation and amnesia are needed during implantation procedures with rapid awakening and extubation after the surgery. We chose inhalation anesthesia supplemented with small doses of fentanyl or thiamylal. Monitoring for AICD implantation should be less invasive, continuous and rapid in responsiveness. For brain and cardiac monitoring, a combination of near infrared spectroscopy and transesophageal echocardiography was quite useful.

Mutagenicity of 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid treated with nitrite in the presence of alcohols

The mutagenicity of a product produced from 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (MTCCA), which is a component in soy sauce, after treatment with 50 mM nitrite at pH 3, 37 degrees C, for 60 min in the presence of 7.5% ethanol was much higher than that in the absence of ethanol during the nitrite treatment. The enhancement of the mutagenicity of nitrite-treated MTCCA by ethanol required simultaneous treatment of MTCCA with nitrite and ethanol. The mutagenicity of MTCCA treated with nitrite in the presence and absence of ethanol was detected in the same fractions on HPLC and was highest for Salmonella typhimurium strain YG1029 possessing elevated O-acetyltransferase activity among the several Salmonella test strains, suggesting that the same mutagen belonging to aromatic compounds was produced both in the presence and absence of ethanol. Methanol, n-propanol and isopropanol as well as ethanol were also observed to have an augmenting effect. However, the sugars glucose and sucrose had no effect. When MTCCA was treated with nitrite in the presence of commercial alcoholic beverages equivalent to 1.25-10% ethanol, Japanese 'sake' and 'shochu' were demonstrated to have a highly augmenting effect and beer, wine, whisky and brandy to have a mildly augmenting effect.

Pentoxifylline and pentifylline inhibit proliferation of human Tenon's capsule fibroblasts and production of type-I collagen and laminin in vitro

After glaucoma filtering surgery, an excessive repopulation of Tenon's capsule fibroblasts (TCFs) with the accumulation of extracellular matrix including collagen types during wound healing may cause scarring of the bleb, resulting in surgical failure. Pentoxifylline (PTX) and pentifylline (PTF), both methylxanthine derivatives, are known to inhibit protein synthesis and proliferation of cells in vitro. We examined the effects of these agents on the proliferation of cultured human TCFs and their production of type-I collagen COOH-terminal peptide (PIP) and laminin to investigate the potential use of the agents as antifibrotic agents after filtering surgery. Both agents inhibited the proliferation of cultured human TCFs and their production of PIP and laminin. The inhibitory effects of PTF on proliferation and production of PIP and laminin were greater than those of PTX. These methylxanthine derivatives may have clinical utility in preventing excessive bleb scarring after glaucoma filtering surgery.

Role of intestinal bacteria in ileal ulcer formation in rats treated with a nonsteroidal antiinflammatory drug

The role of intestinal bacteria in induction and repression of ulcer formation in the ileum of rats treated with one of the nonsteroidal antiinflammatory drugs (NSAIDs), 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl) thiophene (BFMeT), was examined in this study. BFMeT was administered by intragastric gavage once at doses of 500-1,500 mg/kg of body weight to Wistar rats treated with and without antibiotics (bacitracin, neomycin, streptomycin), germ-free rats and gnotobiotic rats, and 72 hr later their gastrointestinal tracts were examined for ulcer formation. A single oral administration of BFMeT induced ileal ulcers in specific pathogen-free rats. However, the rats given antibiotics to reduce the intestinal bacteria had no ulcers. BFMeT-treated germ-free rats and gnotobiotic rats mono-associated with Bifidobacterium adolescentis or Lactobacillus acidophilus also had no intestinal ulcers. However, the drug induced ileal ulcers in gnotobiotic rats mono-associated with Eubacterium limosum or Escherichia coli. An overnight culture of B. adolescentis or L. acidophilus or yogurt containing Bifidobacterium breve and Streptococcus thermophilus, when given as drinking water, inhibited ulcer formation in the ileum of rats treated with BFMeT. Gram staining of the ileal contents of normal rats revealed that 97.4% of the stained microorganisms were Gram-positive rods and only 1.2% were Gram-negative rods. In the group of rats with ulcers induced by BFMeT, the Gram-positive rods decreased by 56.4% and the Gram-negative rods including Escherichia coli, Klebsiella, Proteus and Bacteroides increased by 37.3%. However, in the group of rats administered the Bifidobacterium culture, the Lactobacillus culture or yogurt, the percentages of the Gram-negative rods were decreased. Although Lactobacillus was a major bacterium in the ileum of normal rats, the Gram-negative facultatively anaerobic rods E.coli, Klebsiella and Proteus were increased in the ulcerated ileum of rats treated with BFMeT, suggesting that these bacteria are associated with ulcer formation in rats treated with NSAIDs, and that Lactobacillus and Bifidobacterium inhibit it by repressing the growth of ulcer-inducing bacteria.

[A clinical evaluation of fluconazole in deep seated fungal infections associated with hematological disorders]

The effectiveness of fluconazole on deep seated fungal infections associated with hematological disorders was evaluated in a multicenter clinical study. The underlying diseases included acute myeloblastic leukemia, acute lymphocytic leukemia, malignant lymphoma, adult T cell leukemia, multiple myeloma and others. Fluconazole (FLCZ) was administrated 100-400 mg/day intravenously or orally to 79 patients with systemic fungal infections complicated with hematological disorders and it was possible to evaluate clinical efficacies in 60 patients. 27 patients were diagnosed as having determinate systemic fungal infections and 33 patients suspected fungal infections. The clinical efficacies were 81.5% (22/27) in patients with diagnosed fungal infections and 57.6% (19/33) in patients with suspected fungal infections. The overall clinical efficacy was 68.3% (41/60). No side effects such as gastrointestinal symptoms, vascular pain and renal dysfunction were observed in this study. As for abnormal laboratory test, transient increases in GOT, GPT, Al-P, LDH, serum Na, Cl and decrease in serum K were observed in 9 patients (11.4%). These results indicated that FLCZ has a high therapeutic efficacy on deep seated fungal infections in patients with hematological disorders.

Lens epithelial cell outgrowth and matrix formation on intraocular lenses in rabbit eyes

PURPOSE

To evaluate the presence and distribution of lens epithelial cells (LECs) and extracellular matrix on intraocular lenses (IOLs) implanted in the capsular bag in rabbit eyes.

SETTING

Department of Ophthalmology, Wakayama Medical College, Wakayama, Japan.

METHODS

Five adult albino rabbits had phacoemulsification and IOL implantation in both eyes. Two or 11 months later, the animals were killed by intravenous pentobarbital. The IOLs were removed and observed under scanning and transmission electron microscopy.

RESULTS

In addition to the macrophages and giant cells on the IOLs, all eyes had a monolayer of flattened cells growing out from the residual anterior lens capsule and a fibrous meshwork of extracellular matrix. Unlike those of a macrophagic origin, these cells had no central cytoplasmic elevation of nuclei and few cell surface microvilli and were considered to be proliferating LECs.

CONCLUSION

Lens epithelial cells are involved in the eye's cellular reaction to IOLs and in the formation of extracellular matrix on IOLs. Further study of LEC behavior on IOLs should be done to improve IOL biocompatibility.

Purification and characterization of a fibrinogen-degrading protease in Bacteroides fragilis strain YCH46

A novel fibrinogenolytic protease was purified from Bacteroides fragilis strain YCH46. The protease was extracted from cells by ultrasonic treatment and was purified 425-fold with a recovery of 2.1% by sequential procedures using azocasein as a substrate. The purified protease showed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with an estimated molecular weight of 100 kDa, which was consistent with the value obtained by gel filtration, indicating a monomeric native structure. Its optimal pH, Km, and Vmax for azocasein were 7.5, 0.2%, and 286 U/min/mg, respectively. The protease activity was completely inhibited by addition of 1 mM Hg2+, Cu2+, Zn2+, diisopropyl fluorophosphate, N-ethylmaleimide or p-chloromercuribenzoate but not by the inhibitors of metalloprotease or aspartic protease, suggesting that the enzyme is a serine-thiol-like protease. The protease hydrolyzed azocasein, casein, fibrinogen, gelatin, and azocoll, but not bovine serum albumin, ovalbumin, fibrin, fibronectin, immunoglobulins, transferrin, hemoglobin or types I, III, and IV collagen. The enzyme also hydrolyzed the chromogenic substrates alanyl-alanine p-nitroanilide, L-valyl-alanine p-nitroanilide, alanyl-alanyl-valyl-alanine p-nitroanilide, and glycyl-proline p-nitroanilide, but was inert toward L-alanine p-nitroanilide, alanyl-alanyl-alanine p-nitroanilide, and N-alpha-benzoyl-DL-arginine p-nitroanilide. The protease completely hydrolyzed the alpha-chain of fibrinogen at 37 C within 10 hr and at the same time the time required for clotting of protease-treated fibrinogen by thrombin was prolonged. The fibrinogenolytic activity of a crude extract of B. fragilis was stronger than that of other species of the Bacteroides fragilis group tested: B. ovatus, B. distasonis, B. eggerthii, B. uniformis, and B. thetaiotaomicron. These results suggest that the fibrinogenolytic protease is an important biological factor in Bacteroides infection.

Mutagenicity of soy sauce treated with nitrite in the presence of ethanol or alcoholic beverages

The mutagenicity induced by soy sauce after reaction with 50 mM nitrite at pH 3, 37 degrees C, for 60 min in the presence of 1.25-10% ethanol was reduced in proportion to the ethanol concentration. The mutagenicity of soy sauce treated with nitrite was also reduced in the presence of commercial alcoholic beverages, Japanese sake, wine, 'shochu', whiskey and brandy, but not beer, in proportion to the concentration. The mutagenicity of nitrite-treated tyramine, which is a major precursor of a mutagen in soy sauce treated with nitrite, was strongly reduced in the presence of ethanol, n-propanol or isopropanol and more strongly reduced in the presence of methanol, but was increased twofold in the presence of the sugars glucose or sucrose. The reduction of the mutagenicity of nitrite-treated tyramine required simultaneous treatment of tyramine with ethanol and nitrite. The mutagenicity of tyramine treated with nitrite was clearly reduced in the presence of shochu and whiskey, similarly to ethanol. Analysis by high-performance liquid chromatography revealed that the reduction of the mutagenicity of nitrite-treated tyramine in the presence of ethanol resulted from the reduced production of mutagenic 3-diazotyramine from tyramine.

Extracellular matrix on intraocular lenses

We examined the distribution of extracellular matrix components in the proteinaceous matrix on explanted IOLs using immunohistochemistry to clarify the nature of proteinaceous deposits on the surfaces of IOLs. We examined 15 polymethylmethacrylate (PMMA) IOLs and one silicone IOL explanted from patients. The IOLs were immunostained for cellular fibronectin, types I and IV collagen, and vitronectin. Various amounts of fibronectin, types I and IV collagen, and vitronectin were detected in the extracellular matrix on all IOLs with cellular deposits. Types I and IV collagen and cellular fibronectin were present in the extracellular matrix and were probably the products of cells adhering to the IOLs. Vitronectin in the fibrous extracellular matrix appeared to represent an adsorption material derived from the aqueous humor. These proteinaceous deposits associated with cellular deposits indicate unsuccessful formation of granulation tissue and could influence IOL biocompatibility.

Bioactivation of cysteine conjugates of 1-nitropyrene oxides by cysteine conjugate beta-lyase purified from Peptostreptococcus magnus

To determine the role of cysteine conjugate beta-lyase (beta-lyase) in the metabolism of mutagenic nitropolycyclic aromatic hydrocarbons, we determined the effect of beta-lyase on the mutagenicities and DNA binding of cysteine conjugates of 4,5-epoxy-4,5-dihydro-1-nitropyrene (1-NP 4,5-oxide) and 9,10-epoxy-9,10-dihydro-1-nitropyrene (1-NP 9,10-oxide), which are detoxified metabolites of the mutagenic compound 1-nitropyrene. We purified beta-lyase from Peptostreptococcus magnus GAI0663, since P. magnus is one of the constituents of the intestinal microflora and exhibits high levels of degrading activity with cysteine conjugates of 1-nitropyrene oxides (1-NP oxide-Cys). The activity of purified beta-lyase was optimal at pH 7.5 to 8.0, was completely inhibited by aminooxyacetic acid and hydroxylamine, and was eliminated by heating the enzyme at 55 degrees C for 5 min. The molecular weight of beta-lyase was 150,000, as determined by fast protein liquid chromatography. S-Arylcysteine conjugates were good substrates for this enzyme. As determined by the Salmonella mutagenicity test, 5 ng of beta-lyase protein increased the mutagenicity of the cysteine conjugate of 1-NP 9,10-oxide (10 nmol per plate) 4.5-fold in Salmonella typhimurium TA98 and 4.1-fold in strain TA100. However, beta-lyase had little effect on the cysteine conjugate of 1-NP 4,5-oxide (10 nmol per plate). Both conjugates exhibited only low levels of mutagenicity with nitroreductase-deficient strain TA98NR. In vitro binding of 1-NP oxide-Cys to calf thymus DNA was increased by adding purified beta-lyase or xanthine oxidase.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary myxoid leiomyosarcoma

A primary myxoid leiomyosarcoma arising from the peripheral bronchus of the right middle lobe was removed from a 20 year old man and examined by immunohistochemistry and electron microscopy. The tumor was well circumscribed, yellow-whitish focal polypoid growth into the bronchial lumen and consisted of spindle cells with abundant myxoid substance in the stroma. Intrapulmonary metastasis, invasion to the bronchial wall and a few mitotic figures were found. Immunohistochemically, several, but not all, tumor cells were positive against anti-vimentin, anti-S-100 protein, anti-myosin and anti-muscle specific actin. Ultrastructurally, tumor cells had thin filaments with dense bodies, pinocytic vesicles and discontinuous basal lamina. These findings indicate a myoxoid variant of leiomyosarcoma arising from mesenchyme in the peribronchial area.

[Combination therapy of doxifluridine, pirarubicin and cisplatin for human gastric cancers implanted in nude mice]

In the preclinical study of a new combination therapy for gastric cancer, dFTP, consisting of doxifluridine (5'-DFUR), pirarubicin (THP) and cisplatin (DDP) as a modification of conventional FAP regimen (5-fluorouracil+Adriamycin+DDP), we compared antitumor and toxic effects of two sequential treatment schedules, single injection of DDP before or after 4 daily administrations of 5'-DFUR, on 5 strains of human gastric cancer bearing nude mice. Results indicated that both schedules of the dFTP regimen had potent antitumor effects. There was no significant difference between them. On the other hand, in terms of the host toxicity as observed by body weight loss, the post-DDP schedule was significantly less toxic than pre-DDP. These results suggest that dFTP regimen (post-DDP schedule) may be useful for clinical treatment of gastric cancers.

[Relationship between retained microbubbles and neuropsychologic alterations after cardiac operation]

We studied the relationship between quantity of microbubble retained in the left heart and neuropsychologic alterations after surgery in 21 patients undergoing cardiac surgery including cardiopulmonary bypass. The neuropsychologic change was evaluated by three kinds of psychological test, which mainly analyzed memory and cognition. The microbubble was continuously monitored by the long axis view of the descending aorta of transesophageal echocardiography and then quantitatively analyzed and graded by the on-line computer. More microbubbles were detected in the valve surgery requiring the intracardiac procedure than in coronary artery bypass grafting and neuropsychologic deterioration, although the relationship did not reach statistical significance. Since most of the microbubbles were detected during the unclamping of aorta and the weaning from cardiopulmonary bypass, a technical improvement of the surgical procedures could reduce them. We think that transesophageal echocardiography is useful for monitoring microbubbles during operation.

[Hypopnea according to various definitions and coexisting arousal response in patients with sleep-disordered breathing]

Hypopnea is a type of sleep-disordered breathing, and the apnea plus hypopnea index (AHI) is usually computed to diagnose this condition. Nevertheless, there is no consensus on the definition of hypopnea. To arrive at a reasonable definition, we examined the relationship between arousal response and hypopnea as defined in various ways, in polysomnographs of 20 patients with sleep-disordered breathing. Hypopnea was defined as a 50% reduction in thoraco-abdominal movement of various durations (all of which were more than 10 sec) and coexisting oxygen desaturation of various degree. The ratio of coexisting arousal response for hypopneas was higher when hypopnea was defined as having a relatively long duration and relatively deep desaturation, but more arousal responses were missed. 1) When the threshold duration for hypopnea was fixed at 10 sec, the following results were obtained: With desaturation thresholds of 4% and 2%, the mean ratios of missed arousals were 37% (range, 1-85%) and 12% (range, 0.5-35%), respectively. The hypopneas with only 2% desaturation had coexisting arousal responses with a mean frequency of 49% (range, 27-89%). 2) When desaturation was not included in the definition, the following results were obtained: Hypopneas lasting less than 15 sec had lower frequencies of a coexisting arousal response than did those of longer duration. When the threshold duration for hypopnea was 15 sec, the mean ratio of missed arousal was 16.2% (range, 1.6-32.9%).(ABSTRACT TRUNCATED AT 250 WORDS)

[Unilateral effective renal plasma flow measurement using one-compartment analysis of 99mTc-MAG3 and gamma-camera renography]

The aim of this study was to establish a simple and accurate procedure to calculate the unilateral effective renal plasma flow (ERPF) using 99mTc-MAG3 gamma-camera renographyl. Eleven patients with urological disorders were studied with 99mTc-MAG3 to calculate the renal uptake ratio (RUR), which was defined as the ratio of absorption-corrected renal counts within 1-2 min after intravenous injection to injection radioactivity measured with a gamma-camera. We assumed that 99mTc-MAG3 was distributed in the circulation, moved from the circulation to the kidneys, and was excreted solely from the kidneys. We thus adopted an one-compartment model to calculate 99mTc-MAG3 clearance (CLMAG) using RUR. Sequential p-aminohippurate (PAH) clearance study was performed as a gold standard in all the patients to compare CLMAG and PAH clearance. Obtained CLMAG correlated well with PAH clearance, and this one-compartment model seemed appropriate for describing CLMAG. Unilateral ERPF was accurately measured within two minutes after the intravenous injection of 99mTc-MAG3 in conjunction with the renal imaging study. This procedure is simple and reliable, and requires no blood or urine sampling.