Two new yeasts, Trichosporon debeurmannianum sp. nov. and Trichosporon dermatis sp. nov., transferred from the Cryptococcus humicola complex

Cryptococcus humicola, as currently defined, shows intraspecific rRNA gene sequence differences. Three strains of this species produced arthroconidia on cornmeal agar and belonged to the genus Trichosporon in a molecular phylogeny. They clustered with the species possessing Q10 as the major ubiquinone and were serotype I. Sequence analyses clearly revealed that they were two new Trichosporon species. The names Trichosporon dermatis sp. nov. (= CBS 2043T) and Trichosporon debeurmannianum sp. nov. (= CBS 1896T) are proposed for these strains.

[Mycological and serological diagnosis of cryptococcosis]

Methods for the diagnosis of cryptococcosis have been established, including serotyping and serodiagnosis. Slide agglutination tests with factor sera, the phenol oxidase test, and the growth test at 37C are used for rapid identification of Cryptococcus neoformans. We identified 140 strains and found that 86, 10, and 4% of the isolates were serotypes A, D, and A-D, respectively. Twelve of 14 serotype D strains were isolated from cutaneous cryptococcosis. The most reliable method of serodiagnosis is the latex agglutination (LA) test for detection of polysaccharide antigen combined with protease pretreatment. The LA test is also used for prognosis. The clearance of cryptococcal polysaccharide antigen often takes a few years after treatment. To model the persistence of cryptococcal polysaccharides, we examined the clearance of antigen from the blood of rabbits injected with polysaccharide. The distribution and elimination half-lives of the antigen suggest the prolonged survival of C. neoformans. Recently, the number of cases of C. albidus and C. laurentii has been increasing. The antigenic pattern and the sensitivity of C. albidus in the LA test are the same as that of C. neoformans serotype A. In contrast, C. laurentii does not react with factor sera for C. neoformans and the reactivity with sensitized latex is extremely low. These results were supported by the chemical structures of polysaccharides from these species. We should consider non-neoformans cases in both the identification of isolates and in serodiagnosis.

[Usefulness of right ventricular Doppler index for predicting outcome in patients with dilated cardiomyopathy]

OBJECTIVES

Left ventricular Doppler index (LVDI) is believed to be a useful echocardiographic index of systolic and diastolic ventricular function. However, the usefulness of right ventricular Doppler index (RVDI) remains uncertain, especially in dilated cardiomyopathy. The predictive value of RVDI for estimating long-term cardiac events, including cardiac death, was investigated.

METHODS

Fifty-nine consecutive patients with dilated cardiomyopathy (41 males and 18 females, mean age 52 +/- 15 years) were enrolled in this follow-up study. RVDI and LVDI were calculated as follows: DI = (isovolumic contraction time + isovolumic relaxation time)/ejection time.

RESULTS

During a follow-up period of 3.7 +/- 3.0 years, 27 (46%) of the patients exhibited cardiac events, including cardiac death (n = 9), heart failure (n = 16) and tachyarrhythmias (n = 2) requiring in-hospital treatment. Patients with these cardiac events had higher LVDI and RVDI at the initial follow-up examination, and RVDI had a significant linear correlation with LVDI (LVDI = 0.550 + 0.452 x RVDI, r = 0.530, p = 0.0001). The 6-year survival rate was significantly lower in patients with both LVDI > or = 0.78 and RVDI > or = 0.49 than in other patients (50% vs 75%, respectively, p = 0.009). Cox proportional hazards model analysis showed that RVDI > or = 0.49 was the independent predictor of cardiac events (p = 0.0153) and cardiac death (p = 0.0003).

CONCLUSIONS

RVDI is clinically useful for estimating the outcome of patients with dilated cardiomyopathy.

Phylogenetic and taxonomic heterogeneity of Cryptococcus humicolus by analysis of the sequences of the internal transcribed spacer regions and 18S rDNA, and the phylogenetic relationships of C. humicolus, C. curvatus, and the genus Trichosporon

The phylogenetic and taxonomic heterogeneity of a rare opportunistic yeast pathogen, Cryptococcus humicolus, was revealed by analysis of the sequence of the internal transcribed spacer (ITS) region. Sixteen strains of C. humicolus showed a wide diversity in their ITS sequences. In addition, their 18S rDNA sequences were determined and used to analyze the phylogenetic relationships among C. humicolus and related yeasts. On trees constructed by the Neighbor-Joining and Maximum Parsimony methods, C. humicolus strains were phylogenetically closely related to each other with the exception of one strain, and they clustered with C. curvatus and Trichosporon species with high bootstrap values. Three C. humicolus strains obtained from humans belonged to the group of Trichosporon serotype I species. The results suggest that C. humicolus is a genetically heterogeneous species which should be reclassified on the basis of DNA sequence data.

Telomerase activity in giant condyloma acuminatum

A 46-year-old male came to our hospital 1 month after noticing a 2-cm penile tumor. Since malignant findings such as atypical cells and mitosis were not observed in the frozen sections obtained at operation, the pathological diagnosis of this tumor was giant condyloma acuminatum. This tumor was analyzed by a telomeric repeat amplification protocol method, and telomerase activity was revealed. For comparison, a case of squamous cell carcinoma and a case of condyloma acuminatum were examined. Telomerase activity was observed in our case and in the case of squamous cell carcinoma. To our knowledge, this is the first case of telomerase activity in giant condyloma acuminatum ever reported. In addition to the histological examination, measurement of telomerase activity may provide valuable objective diagnostic information on evaluating the degree of malignancy of giant condyloma acuminatum and in obtaining a differential diagnosis between the benign and malignant.

Structural studies of the antigen III cell wall polysaccharide of Trichosporon domesticum

Cell wall and soluble polysaccharides that reacted with Trichosporon domesticum factor III serum were isolated from the type strain of T. domesticum. The fractions contained O-acetyl groups, which contributed to the serological reactivity. The antigenic structure was characterized by chromatographic and spectroscopic methods. The polysaccharide has an alpha-(1-->3)-D-mannan backbone with hetero-oligosaccharide side chains consisting of a 2-O-substituted beta-D-glucuronic acid residue bound to O-2 of the mannose residue, beta-D-xylopyranosyl residues located in the middle of the side chain, and a nonreducing terminal alpha-L-arabinopyranosyl residue bound to 0-4 of xylose. The mannan backbone is O-acetylated at O-6 of the mannose residues.

An adult case of congenital external carotid-jugular arteriovenous fistula with reversible circulatory insufficiency in the cerebellum and lower brain stem

A 27-year-old man with congenital external carotid-jugular arteriovenous fistula presented with a diminished level of consciousness and an ataxic gait. Axial fluid-attenuated inversion-recovery (FLAIR) MR imaging revealed venous congestion, a dilated right jugular vein, and an area of high signal intensity in the brain stem and cerebellum. Angiography showed a dilated right external carotid artery and jugular vein and the presence of a fistula. After coil embolization of the fistula, axial MR FLAIR images showed only a few areas of high signal intensity in the brain stem and cerebellum. The causal factor was venous congestion in the inferior petrosal sinus and basilar plexus due to high blood pressure in the jugular vein. This case is presented for its unusual clinical and radiologic findings.

Reversal of LRP-associated drug resistance in colon carcinoma SW-620 cells

Resistance to multiple drugs is mediated by lung resistance-related protein (LRP) as well as P-glycoprotein (P-gp) and multidrug resistance protein (MRP). The levels of expression of LRP mRNA and LRP in a human colon carcinoma cell line, SW-620, were increased by the differentiation-inducing agent, sodium butyrate (NaB). Treatment of SW-620 cells with NaB for 2 weeks conferred resistance to adriamycin (ADM) and VP-16. The resistance was almost completely reversed by PAK-104P, a pyridine analog, but not by cepharanthine. ADM accumulated mainly in the nuclei of SW-620 cells not treated with NaB and in the cytoplasm of SW-620 cells treated with NaB. When the NaB-treated SW-620 cells were incubated with ADM in the presence of PAK-104P, the accumulation of ADM in nuclei was substantially increased. Isolated nuclei from untreated cells accumulated more ADM than nuclei from NaB-treated cells. Efflux of ADM from the nuclei isolated from NaB-treated cells was enhanced. PAK-104P and an antibody against LRP increased the accumulation of ADM in the isolated nuclei from NaB-treated cells, and inhibited the enhanced efflux of ADM from the nuclei. These findings suggest that at least in part, PAK-104P reverses LRP-mediated drug resistance by inhibiting the efflux of ADM from nuclei. PAK-104P may be useful for reversing MDR in tumors that overexpress LRP.

MRI appearance of a leiomyoma of the female urethra

Leiomyomas are rare in the urinary tract, with the kidney capsule being the most common location [1]. Leiomyoma of the female urethra is very rare. In 1992, Cheng et al. reviewed a total of 29 cases. They concluded that urethral leiomyoma is a rare condition that is difficult to distinguish clinically from other urethral lesions and that a histological diagnosis is essential [2]. Although we agree that the histological diagnosis is essential, magnetic resonance imaging (MRI) provides useful pre-operative information in cases of leiomyoma of the female urethra, as our present case indicates. To our knowledge we report the second case of a primarily diagnostic approach with MRI for leiomyoma of the female urethra. Ikeda, R. (2001). Clinical Radiology56, 76-79.

Reversal of LRP-associated drug resistance in colon carcinoma SW-620 cells

Resistance to multiple drugs is mediated by lung resistance-related protein (LRP) as well as P-glycoprotein (P-gp) and multidrug resistance protein (MRP). The levels of expression of LRP mRNA and LRP in a human colon carcinoma cell line, SW-620, were increased by the differentiation-inducing agent, sodium butyrate (NaB). Treatment of SW-620 cells with NaB for 2 weeks conferred resistance to adriamycin (ADM) and VP-16. The resistance was almost completely reversed by PAK-104P, a pyridine analog, but not by cepharanthine. ADM accumulated mainly in the nuclei of SW-620 cells not treated with NaB and in the cytoplasm of SW-620 cells treated with NaB. When the NaB-treated SW-620 cells were incubated with ADM in the presence of PAK-104P, the accumulation of ADM in nuclei was substantially increased. Isolated nuclei from untreated cells accumulated more ADM than nuclei from NaB-treated cells. Efflux of ADM from the nuclei isolated from NaB-treated cells was enhanced. PAK-104P and an antibody against LRP increased the accumulation of ADM in the isolated nuclei from NaB-treated cells, and inhibited the enhanced efflux of ADM from the nuclei. These findings suggest that at least in part, PAK-104P reverses LRP-mediated drug resistance by inhibiting the efflux of ADM from nuclei. PAK-104P may be useful for reversing MDR in tumors that overexpress LRP.

Fine structure of transforming-type granules in mucous cells in the early postnatal rat parotid gland when processed by rapid freezing followed by freeze-substitution fixation

The present study was designed to clarify the more precise ultrastructural feature of granules, especially mucous granules in the early postnatal rat parotid gland by using rapid freezing followed by freeze-substitution fixation. The parotid gland of Wistar rats (aged 0-10 days) was removed under anesthesia and immediately underwent cryofixation followed by substitution with osmium tetroxide. After fixation, the samples were embedded in Epon-Araldite, cut into ultrathin section, and then examined by transmission electron microscopy. Electron microscopy showed that the mucous granules of samples treated by freeze-substitution fixation had low electron density and were almost spherical in shape with a clear limiting membrane. By Day 5, granules that were a little more electron dense than mucous granules, granules with a more electron dense portion at their periphery, and heterogeneous granules with an internal highly electron dense portion were found. Moreover, cells containing both homogeneous granules with a high electron density similar to that of mature serous granules and heterogeneous granules were observed. These findings demonstrated that the morphology of the transforming-type mucous granules by chemical fixation in the previous study was an artifact and, as a result, strongly suggested that on the sequential morphological changes of transitional mucous/serous granules by rapid freezing method in the present study, the mucous cells in the early postnatal rat parotid gland undergo transformation to serous cells.

Reversal of P-glycoprotein and multidrug-resistance protein-mediated drug resistance in KB cells by 5-O-benzoylated taxinine K

A newly synthesized taxoid originally from the Japanese yew Taxus cuspidata, 5-O-benzoylated taxinine K (BTK) was examined for its ability to reverse P-glycoprotein (P-gp) and multidrug resistance protein (MRP)-mediated multidrug resistance. BTK reversed the resistance to paclitaxel, doxorubicin (ADM), and vincristine (VCR) of KB-8-5 and KB-C2 cells that overexpress P-gp by directly interacting with P-gp. BTK also moderately reversed the resistance to ADM of KB/MRP cells that overexpress MRP. However, BTK neither inhibited the transporting activity of MRP nor reduced intracellular glutathione levels in KB/MRP cells. BTK shifted the distribution of ADM in KB/MRP cells from punctate cytoplasmic compartments to the nucleoplasm and cytoplasm by inhibiting acidification of cytoplasmic organelles. These two functions of BTK make it able to reverse both P-gp- and MRP-mediated MDR. BTK in combination with ADM should be useful for treating patients with tumors that overexpress both P-gp and MRP.

Serological relationships of Cryptococcus spp.: distribution of antigenic factors in Cryptococcus and intraspecies diversity

The antigenic formulas of 34 species in the genus Cryptococcus were determined by using type strains and eight factor sera prepared from adsorption experiments with Cryptococcus neoformans serotypes. These antigenic factors were shared by 19 species. The strains used could be divided into eight serological groups. The patterns of groups 1, 2, 3, 5, and 6 were the same as the patterns of C. neoformans serotypes A, D, A-D, B, and C, respectively. The species belonging to group 4 reacted to factor sera 1, 2, and 3. Group 7 contained one species that reacted only to factor serum 1. The 15 species in group 8 did not react to any of the factor sera used. Compared to the reported molecular phylogenetic tree, the serological and phylogenetic data were correlated in the Filobasidium lineage. All the members of the albidus clade in the Filobasidium lineage had antigens 1, 2, and 3, and all the strains in the magnus clade belonged to serogroup 8. Moreover, intraspecies diversity was examined using strains of C. curvatus, C. humicolus, and C. laurentii. Serological heterogeneity was observed in the species C. humicolus and C. laurentii, as well as in phylogenetic relationships previously published. Using serological features, similarities and differences between Cryptococcus species were demonstrated. Our study contributes to a better description of the genus Cryptococcus and related species phenotypically and phylogenetically.

Histopathological study of female beagle dogs for four year treatment with subcutaneous implantation of chlormadinone acetate (CMA)

The histopathological changes related to chlormadinone acetate (CMA) implantation were examined using female beagle dogs given 10mg/kg for four years. All control animals showed sign of estrus during the experiment, with periods of anestrus of normal duration. In contrast, estrus was completely inhibited in the CMA-implanted animals. Histopathologically, uterine sections from the CMA-implanted animals showed cystic glandular hyperplasia, but no histologic evidence of endometritis, myometritis, and pyometra was found. In the ovaries of the CMA-implanted animals, developing ovarian follicles were observed but no mature follicles were noted in addition to an absence of corpus luteum. No remarkable changes were observed in the liver, adrenal, mammary gland, gallbladder and implanted site. Furthermore, the intensity of staining and number and size of ACTH-and LH-positive cells in the pituitary sections of CMA-implanted animals were not different from control animals. It was concluded, therefore, that subcutaneous implantation of CMA is a potential drug-delivery system for reducing changes due to antigonadotropic and glucocorticoid-like activities and characteristic histopathological changes in the uterus due to progestagenic activity.

[Multimodality therapy for synchronous liver metastases of gastric cancer--significance of aggressive hepatic resection of liver lesions]

We analyzed 15 gastric cancer patients with synchronous liver metastases, and studied the significance of hepatic resection with multimodality therapy. 1. Both gastric and hepatic resections followed by intra-arterial or systemic chemotherapy were performed for six patients, two of whom had intra-operative MCT or EIT. The survival time of four patients without recurrence was 5 Y 4 M, 4 Y 5 M, 2 Y 4 M and 11 M. Two patients died of recurrence in the retroperitoneum or residual liver 3 Y 10 M and 8 M after therapy, respectively. The three-year survival rate was 83%. 2. The longest survival among the five patients treated with gastric resection without hepatic resection followed by intra-arterial or systemic chemotherapy was 1 Y 1 M. 3. Four patients with non-curative factors (P, N, M) were treated with systemic chemotherapy only, and the longest survival was 1 Y 1 M. In conclusion, when local control is obtained during surgery in patients with gastric cancer with synchronous liver metastasis, aggressive hepatic resection supported with MCT or EIT should be performed on liver lesions to improve the prognosis.

[Acquired renal cystic disease]

In 1977, Dunnill et al. described a new disorder, bilateral multiple renal cystic disease. It occurred among hemodialysis patients whose original illness had not been cyst-related. Acquired cystic disease of the kidney (ACDK) is commonly observed in patients undergoing hemodialysis. The incidence of ACDK is 40-50% in reports of autopsy and surgical specimens, rising to more than 90% after 5-10 years of dialysis. The volume of the kidneys decreases in the first 3 years of dialysis and then increases as the rate of cyst formation increases. In male patients undergoing long-term hemodialysis the incidence of ACDK is markedly high. ACDK is also found in patients before hemodialysis. The primary concern in patients with ACDK is the increased incidence (5-19%) of renal cell carcinoma (RCC). The incidence is about twelve to eighteen times higher than that in the general population and the cancers may be asymptomatic. Therefore, screening is essential if carcinomas are to be detected early. Regular screening by ultrasonic examination or CT scan is needed. A patient requires nephrectomy when the kidney cancer exists or is suspected by dynamic CT scan. Nephrectomy is performed only on the side with renal mass. It has been argued that RCC associated with ACDK are innocuous and do not predispose the patient to an increased risk of death from RCC. RCC arising from ACDK is considered to be a tumor of low malignant potential, compared with classic RCC. However, RCC has been reported to metastasize in 16% of the patients on dialysis and to be the cause of death in 2% of the kidney transplant recipients. The etiology of ACDK is unclear and its incidence increases with the duration of dialysis. ACDK patients have a propensity to develop adenocarcinoma. The increased incidence of RCC in ACDK patients warrants careful radiologic monitoring of end-stage kidneys in selected patients.

Wall correction factors for calibration of plane-parallel ionization chambers with high-energy photon beams

Most dosimetry protocols recommend that calibration of plane-parallel ionization chambers be performed in an electron beam of sufficiently high energy by comparison with cylindrical chambers. For various plane-parallel chambers, the 1997 IAEA TRS-381 protocol includes an overall perturbation factor pQ for electron beams, a wall correction factor p(wall) for a 60Co beam and the product of two wall corrections k(att)k(m) for 60Co in-air calibration. The recommended values of p(wall) for plane-parallel chambers, however, are limited to certain phantom materials and a 60Co beam, and are not given for other phantom materials and x-ray beams. In this work, the p(wall) values of the commercially available NACP, PTW/Markus and PTW/Roos plane-parallel chambers in a solid water phantom have been determined with 60Co and 4 and 10 MV photon beams. The k(att)k(m) values for the NACP and PTW/Markus chambers have also been obtained. The wall correction factors p(wall) and k(att)k(m) have been determined by intercomparison with a calibrated Farmer chamber. The average value of p(wall) for these plane-parallel chambers was 1.005 +/- 0.1% (1 SD) for 60Co beams and 1.007 +/- 0.2% (1 SD) for both 4 MV and 10 MV photons. The k(att)k(m) values for the NACP and PTW/Markus chambers were about 1.5% lower than other published data.

Atrophic effects of antiandrogen, chlormadinone acetate (CMA) on dog prostate with spontaneous benign prostatic hyperplasia

The atrophic effect of a synthetic steroidal antiandrogen, chlormadinone acetate (CMA), on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Male beagle dogs (5-8 years old) were divided into four experimental groups. Group 1 consisted of untreated controls. Groups 2 to 4 received CMA 0.03, 0.1, and 0.3 mg/kg/day, p.o., respectively, for 6 months. In group 1, glandular hyperplasia of the prostate was clearly detected. The glandular epithelial cells showed uniformly intense nuclear staining for androgen receptor (AR). AR was also localized in the nuclei of the fibro-muscular stromal cells. Immunoreactivity of 5 alpha-reductase type I was positive in most glandular epithelial cells. No fibro-muscular stromal cells were stained. Immunolocalization of 5 alpha-reductase type II was clearly detected in the interacinar fibro-muscular stromal cells, but not in the glandular epithelial cells. In groups 2 to 4, CMA produced marked atrophy of the glandular epithelium. The interacinar fibro-muscular stroma was prominent. The nuclear staining for AR in both epithelial and stromal cells was remarkably decreased. Furthermore, the immunoreaction for 5 alpha-reductase type I in most glandular epithelial cells was negative or very weak. The immunoreaction of 5 alpha-reductase type II in the interacinar fibro-muscular stromal cells was negative or very weak. These results indicate that the uptake of testosterone and/or its androgenic effect on the prostate may be suppressed by CMA. The decreased AR-immunostaining may be explained by the decrease in the number of AR and/or antibody binding sites for AR. Therefore, the atrophy after treatment with CMA may be due to shrinkage of both glandular and stromal compartments in the prostate tissue.

[The relationships among DNA ploidy type determined by laser scanning cytometry, the overexpression of p53 protein and the numerical aberrations of chromosome 7 in bladder cancer]

The cellular DNA content of certain malignancies is regarded as a prognostic parameter. The mutant p53 is thought to destabilize centrosome replication, which leads to aberrant mitosis and chromosome instability. We investigated the relationship among DNA ploidy pattern type, numerical aberrations of chromosome 7 and p53 overexpression in 20 transitional cell carcinomas of the urinary bladder. The DNA ploidy pattern type was determined by laser scanning cytometry, while p53 overexpression was investigated immunohistochemically. Using fluorescence in situ hybridization with chromosome-specific probes, the copy number of chromosome 7 was counted by touch preparations of interphase nuclei. The cytometric analysis revealed that the DNA patterns were highly correlated with both the numerical aberrations of chromosome 7 (p = 0.0002) and the overexpression of p53. The incidences of p53 overexpression in DNA aneuploid tumors and DNA diploid ones were 78% and 10%, respectively (p = 0.0017). Our results suggest that the overexpression of abnormal p53 protein induces DNA aneuploidy in bladder cancer.

[Intracardiac floating thrombi in patients with acute pulmonary thromboembolism]

The mortality and morbidity associated with residual intracardiac floating thrombi in patients with acute pulmonary thromboembolism remain uncertain. Thirteen patients (2 men and 11 women, mean age 56 +/- 15 years) with pulmonary thromboembolism underwent echocardiography within 24 hours from onset of symptoms. Four patients (31%) had floating intracardiac thrombi in the right heart: 3 in the right atrium and one in the inferior vena cava. The time to evaluation by echocardiography was shorter than in the patients without thrombi. The thrombi disappeared shortly (3.2 +/- 2.4 hr) after thrombolysis without adverse effects in these patients. After thrombolysis, clinical symptoms improved and pressure gradient between the right ventricle and right atrium decreased significantly (p < 0.01) from baseline 47 +/- 6 to 26 +/- 5 mmHg. Major bleeding complications occurred in 3 (43%) of the patients who underwent thrombolysis. Right-side intracardiac floating thrombus was easily detectable by early echocardiography. Thrombolytic agents are likely to be effective in patients with intracardiac floating thrombi.

Ommochrome genesis in an albino strain of a terrestrial isopod

The contents of tryptophan (Trp) metabolites and the activities of the enzymes involved in ommochrome biosynthesis were measured in an albino strain of a terrestrial isopod Armadillidium vulgare. There was little difference between the Trp content in the albino mutant and that in the wild type, although the contents of 3-hydroxykynurenine (3-OH-Kyn), 3-hydroxyanthranilic acid (3-OH-AA) and xanthommatin in the albino were significantly lower than those in the wild type. Tryptophan 2,3-dioxygenase (TDO) activity in the albino was extremely low, while the activities of Kyn-3-hydroxylase and kynureninase did not differ significantly between the two phenotypes. The extremely low activity of TDO is probably one of main reasons why almost no ommochrome pigment is produced in the albino mutant.

Histopathological studies of subcutaneous implantation of chlormadinone acetate (CMA) for preventing estrus in queens

The efficacy and clinical safety of chlormadinone acetate (CMA) in preventing estrus were assessed in queens on condition that CMA was subcutaneously implanted in siliastic rubber. Thirteen queens were divided into the following four groups according to dose of CMA-administered: group 1 (n = 3), control; group 2 (n = 3), 2.5 mg/kg; group 3 (n = 3), 5 mg/kg; group 4 (n = 4), 20 mg/kg. The implants were left in these queens for 12 months after implantation. All control animals showed signs of estrus during the experiment, with periods of anestrus of normal duration. In contrast, estrus was completely inhibited in the CMA-treated groups. Histopathologically, the uterus from group 4 had coiled branched glands with little secretion in the endometrium. Mammary glands from the CMA-treated groups showed mild lobular development with acinar proliferation and secretion. Sections through the other organs (pituitary gland, adrenal gland, ovary, and implant site) had no distinct or consistent changes that could be related to the CMA-treated. It was concluded, therefore, subcutaneous implantation of CMA could be the good drug-delivery system for reducing changes due to the antigonadotropic and glucocorticoid-like activities and serious condition in the uterine and mammary gland due to progestagenic activity.

Intraspecies diversity of Cryptococcus laurentii as revealed by sequences of internal transcribed spacer regions and 28S rRNA gene and taxonomic position of C. laurentii clinical isolates

The intraspecies diversity of an opportunistic yeast pathogen, Cryptococcus laurentii, was revealed by analysis of the sequences of the internal transcribed spacer regions and the 28S rRNA gene. Ten strains of C. laurentii were grouped into two major phylogenetic groups and were further divided into at least seven species. Four of the strains isolated from patients did not represent a single species but showed heterogeneity. These results suggest that C. laurentii is a genetically heterogeneous species, and this must be taken into consideration when identifying C. laurentii clinical isolates.

Intranuclear localization of proliferating cell nuclear antigen during the cell cycle in renal cell carcinoma

OBJECTIVE

To investigate, with laser scanning cytometry (LSC), proliferating cell nuclear antigen (PCNA) expression during the cell cycle in renal cell carcinoma.

STUDY DESIGN

DNA ploidy and intracellular localization of PCNA in renal cell carcinoma were determined using LSC and immunohistochemistry. The subjects were nine patients who had received surgery for renal cell carcinoma. After DNA ploidy analysis, the glass slides were restained by immunohistochemistry of PCNA. LSC allowed direct observation of PCNA localization during the cell cycle because we could obtain immunohistochemical staining of PCNA as a function of cell cycle phase for individual cells.

RESULTS

PCNA was not demonstrated in the nuclei of G0/G1 cells. PCNA expression increased from the S phase of the cell cycle. PCNA rapidly degraded at the end of the G2 phase. In the late G2 and M phase, PCNA was not detected in almost any nucleus.

CONCLUSION

LSC allows morphologic observation of the intracellular distribution of PCNA during the cell cycle in renal cell carcinoma.