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To prospectively evaluate the breast cancer detection of prone breast positron emission tomography (PET) images in comparison with supine whole-body PET images.One hundred and eighteen female patients (age range 28-91 years) with 122 lesions suspected of having breast cancer underwent fluorine-18 fluorodeoxyglucose PET for preoperative staging. After the whole-body image was acquired, prone breast PET imaging was performed. The findings from both images were compared with the histopathologic results. Sensitivity, specificity, positive predictive value, negative predictive value (NPV), and accuracy were used to compare the diagnostic accuracy of prone breast PET images with that of whole-body PET images.Sensitivity, specificity, positive predictive value, NPV, and accuracy of whole-body PET images were 83, 50, 97, 17, and 80%, and of prone breast PET images they were 95, 50, 96, 43, and 93%. Ten of 114 breast cancerous lesions (8.8%) were detected on prone breast PET images alone. Statistical difference was found between the sensitivity, accuracy, and NPV of prone breast PET images and those of whole-body PET images (P0.0001 for sensitivity and accuracy and P0.0009 for NPV).Our data about the 122 lesions, suspected of breast cancer, with regard to the usefulness of prone breast PET imaging indicate that prone breast PET images are effective in detecting breast cancer.

Determination of the region of interest (ROI) for dynamic renal function has been highly discordant among operators because of the dependence on factors such as the rate of injection of radioactive medicines, constitution, and renal function. To simplify this problem, we developed a computer algorithm that provides automatic analysis for both localization of the kidney and automatic determination of ROIs using computed tomographic (CT) images. The bilateral kidneys were extracted from enhanced CT images, and the CT pixel size was adjusted to dynamic renal function images. The template-matching technique was used for these images, and the kidney renal location was analyzed on additional functional images constructed by dynamic renal function images. As a result, we were able to obtain time-activity curves of both renal function and quantified glomerular filtration rate (GFR). In conclusion, the computer algorithm we developed was considered to provide reliable results, apart from the variability among operators, because of its good reproducibility.

The temporal image subtraction technique was applied to bone scintigraphy, using Photoshop (commercially available image processing software) and Morpher (public domain warping software). For the temporal subtraction images, 81 subtraction images (19 cases) were prepared by a method used to subtract the previous images from the current ones. Registration of the current and previous images was performed by manual operation using Photoshop, and warping was done using the warping function of Morpher. In addition, difference images prepared after correcting the distributions of radioactive isotopes of the current and previous images using the count of the pelvic region were also examined. Compared with manual operation, alignment of images by warping improved registration and reduced the generation of pseudo-images of subtraction images. The rate of identification of abnormal accumulation-enhanced regions and subjective evaluation by doctors was improved for warping more than for manual operation. Furthermore, abnormal hot regions, which are difficult to find in film images, could be found in three subtraction images. In addition, it was confirmed that abnormal hot regions become more visible in many cases by preparing subtraction images after correcting the count between images using the count of the pelvic region. Thus, it is suggested that the temporal image subtraction technique in bone scintigraphy enables more accurate observation of enhancement of or changes in abnormal hot regions, which will support diagnostic reading. It is considered that enhancement of or changes in abnormal hot regions will be more accurately understood through further detailed discussion in the future.

The capability of guinea pig epidermal extracts to hydrolyze deoxyribonucleic acid has been studied. The results of investigation by gel filtration on Sephadex G-75 column and by viscometry on the mode of hydrolysis of deoxyribonucleic acid by epidermal extracts revealed that deoxyribonucleic acid was degraded by both endonuclease and exonuclease activities. The exhaustive digestion by epidermal extracts yielded the complete degradation of deoxyribonucleic acid to mononucleosides or further metabolites. The enzyme systems involved in the deoxyribonucleic acid degradation include at least an endonuclease, an exonuclease and a phosphatase.

Guinea pig epidermal DNAase I was purified from an epidermal extract by a procedure including DEAE-cellulose chromatography, Sephadex G-100 gel filtration and Con A-Sepharose affinity chromatography. The purified enzyme contained no detectable activities of acid DNAase, alkaline RNAase, phosphodiesterase or acid or alkaline phosphatase, but was contaminated with acid RNAase activity. The molecular weight of the enzyme was estimated to be 33 000 by sucrose density gradient centrifugation and Sephadex G-100 gel filtration. Its isoelectric point is 5.2 +/- 0.1. The enzyme requires divalent cations and exhibits two pH optima that are dependent on divalent cations: in the presence of Mn2+, the optimum pH is about 7.5 in 50 mM Tris-HCl buffer and in the presence of Mn2+, the pH is 6.4 in 50 mM cacodylate-HCl buffer. The enzyme hydrolyzes native DNA about 6-times faster than denatured DNA, producing 5'-phosphoryl and 3'-hydroxyl terminated oligonucleotides with an average chain length of about eight nucleotides, and converts double-stranded and circular DNA to relaxed and linear forms. The enzyme is inhibited by G-actin and antiserum against bovine pancreatic DNAase A. Thus this enzyme is classified as DNAase I.

Acid phosphatase of newborn rat epidermis was purified about 270-fold by a procedure including acid treatment, CM-cellulose, DEAE-cellulose chromatography, and gel filtration on Sephadex G-100. The purified enzyme had a pH optimum of 5.0 and an optimal temperature of 40°C. The enzyme was not activated by divalent cations, ethylenediaminetetraacetic acid or 2-mercaptoethanol, and it was inhibited by p-chloromercuribenzoate. The inhibition pattern by fluoride and by L(+) tartrate was competitive. The Km value for p-nitrophenyl phosphate was 3.84×10−5 M, and the molecular weight was about 73, 000. The enzyme appeared to be a nonspecific acid phosphatase. Intracellular localization of acid phosphatase in the epidermis was discussed.

Isoelectric focusing and concanavalin A-Sepharose chromatography were used to study the multiple forms and glycoprotein natures of so-called lysosomal hydrolases from psoriatic scales. Acid phosphatase appeared as 5 different forms with pI values of 6.5, 6.1, 5.8, 5.6 and 5.45. Seven isoenzymes of alpha-fucosidase were identified with pI values of 6.4, 6.2, 5.9, 5.75, 5.65, 5.4 and 5.2. Acid alpha-mannosidase activity appeared as one peak with pI value of 6.75 and a weak activity of neutral alpha-mannosidase was present with pI value of 6.7. Incubation of the extract with neuraminidase increased their pI values of acid phosphatase, alpha-fucosidase and alpha-mannosidase to the more basic forms. This finding suggests that epidermal acid phosphatase, alpha-fucosidase and alpha-mannosidase have some N-acetylneuraminic acid residues. In addition concanavalin A-Sepharose column chromatography was also performed to confirm the glycoprotein nature of acid phosphatase. This enzyme was bound to the column and not released from the column even with the treatment of 0.5 M NaCl, but the enzyme was eluted from the column with the treatment of alpha-methyl-D-glucoside.

An acid deoxyribonuclease of guinea pig epidermis hydrolyzes chromatin DNA as well as histone-free DNA. The enzyme degrades approximately 50% of chromatin DNA, while it degrades 90% of histone-free DNA. Guinea pig epidermal extract contains proteolytic activity for histone or chromatin with a pH optimum at around 8.0.

Deoxyribonuclease was isolated from cow snout epidermis and purified approximately 200-fold in specific activity. The enzyme has a pH optimum of 5.5 and a temperature optimum at 50° C. No physiologic cations were required for enzyme activity. Activity was strongly inhibited by zinc sulfate and ammonium sulfate. It was found that the enzyme hydrolyzed native DNA more efficiently than heat denatured DNA. Because the average chain length of the limit digest was approximately 3, the isolated DNase was considered to be an endonuclease acting at many places along the length of the DNA polymer chain. The physiologic role of DNase in nuclear decomposition during epidermal keratinization is discussed.

モルモット表皮抽出液中にはendonuclease typeのdeoxyribonuclease(DN ase)，exonuclease，nucleotidase(phosphatase)が存在していた。表皮でのDNA catabolismは，まずendonucleaseにより高分子DNAはoligonucleotideに分解され，exonucleaseでnucleotideに，さらにnucleotidaseによりnucleosideへと崩壊をうけることが明らかとなつた。DNAの崩壊分解は260～270nmに吸収帯をもつ物質であつたが同定するにはいたらなかつた。

Two chromatographically and enzymatically distinct forms of acid phosphatase have been separated by gel filtration from an extract of guinea-pig epidermis. These enzymes, termed APase 1 and APase 2 , had pH optima for p -nitrophenyl phosphate hydrolysis around 5.0. APase 1 was inhibited by fluoride, L(+) tartrate, and lead nitrate, but was insensitive to formaldehyde and glutaraldehyde. In contrast, Apase 2 was insensitive to fluoride, L(+) tartrate, and lead nitrate, but was sensitive to formaldehyde and glutaraldehyde. K m values for APase 1 and APase 2 with p -nitrophenyl phosphate as substrate were 0.09mM and 0.125 mM, respectively.

Two forms of alpha-fucosidase from newborn rat epidermis were separated by gel filtration on Sephadex G-150. These enzymes termed, fucosidase I which was eluted in the void volume and fucosidase II (molecular weight approximately 50,000). Both enzymes had pH optima for 4-methylumbelliferyl-alpha-L-fucoside hydrolysis between 5.5-6.5. Km values for fucosidase I and II with the same substrate were 3.7 X 10(-5) and 5.4 X 10(-5) M, respectively. Three different forms of new born rat epidermal alpha-fucosidase were separated by isoelectric focusing. Evidence is present which indicates that the electrophoretic heterogeneity of alpha-fucosidase is due in part to the binding of sialic acid to the primary gene product.

Two forms of beta-galactosidase from newborn rat epidermis could be separated by DEAE-cellulose chromatography. Both enzymes showed similar enzymic properties. They had a pH optimum around 3.5--4.5 and the optimal temperature of these enzymes was approximately 60 degrees C. They were not affected by divalent cations, ethylenediaminetetraacetic acid(EDTA) and 2-mercaptoethanol(2-ME), while rho-chloromercuribenzoic acid (PCMB) was a strong inhibitor for each enzyme. These enzymes showed the same Km value (1.25 x 10(-4) M) towards 4-methylumbelliferyl-beta-D-galactoside. However they had different isoelectric points at pH 6.3 and 9.0, respectively. Six different forms of beta-galactosidase activity were found by using isoelectric focusing. When the crude extract was incubated with neuraminidase before electrofocusing, the acidic forms of the enzyme were largely lost and converted to more basic forms without loss of the total activity. This finding suggests the glycoprotein nature of newborn rat epidermal beta-galactosidase.

1) ラット表皮と毛根抽出液のDNase活性を感高の高いアイソトープ法で測定し, その性質を調べた。 2) 表皮DNaseは5.0付近に, 毛根DNaseは4.5～5.0付近に至適pHを示した。 3) 2価陽イオンは表皮DNaseの活性にほとんど変化をあたえなかつたが, 毛根DNaseはCa++, Mg++, Mn++, Co++などにより, かなり活性が上昇した。 4) 表皮抽出液中にDNase inhibitorの存在を示唆する結果がえられた。 5) 表皮DNase活性は表皮の上方に分布していると考えられる。

ラットとモルモット表皮抽出液にはphosphodiesterase(PDase)I，IIの活性が存在していた。PDase Iは9に，PDase IIは5付近に至適pHを示した。Mg++はこれらの酵素活性を上昇させた。EDTAはPDase Iをいちじるしく阻害し，PDase IIにたいしては逆にわずかではあるが活性を上昇させた。PDase IはTriton X-100(終濃度0.1%)により3.4倍も酵素活性は上昇した。表皮の核酸異化過程における本酵素の関与について考察した。