Therapeutic effect of adriamycin encapsulated in long-circulating liposomes on Meth-A-sarcoma-bearing mice

Long-circulating liposomes modified with a uronic-acid derivative, palmityl-D-glucuronide (PGIcUA), have been developed previously for the passive targeting of liposomes to tumor tissues. In this study, we examined the therapeutic effect of adriamycin (ADM) encapsulated in PGIcUA liposomes composed of dipalmitoylphosphatidylcholine (DPPC), cholesterol (Chol) and PGIcUA (molar ratio, 40/40/10) since this amount of PGIcUA was enough to endow liposomes with long-circulating activity. Long-circulating activity was also observed with palmityl-D-galacturonide (PGalUA) modified liposomes, suggesting that uronic acid plays an important role in preventing liposomes from being trapped in the reticuloendothelial system (RES). ADM was loaded in liposomes by a remote-loading method. Free or liposomal ADM was injected i.v. into BALB/c mice bearing s.c.-implanted Meth-A sarcoma. The liposomal formulation was efficient for reducing tumors, prolonging survival time and curing the animals, especially in the case of large tumors where free ADM was not. Furthermore, PGlcUA liposomes were more effective than conventional liposomes containing dipalmitoylphosphatidylglycerol (DPPG) instead of PGlcUA for prolonging survival time in mice. It might therefore be appropriate to use PGlcUA liposomes as the carriers of anticancer drugs.

Functional and morphological abnormalities of mitochondria in human cells containing mitochondrial DNA with pathogenic point mutations in tRNA genes

mtDNA with a point mutation in the tRNA(Ile) gene at nucleotide position 4269 found in a patient with fatal cardiomyopathy and mtDNA with a point mutation in the tRNA(Arg) gene at 10410 found in a patient with Alpers disease were transferred cytoplasmically to rho zero HeLa cells (HeLa cells lacking mtDNA) to determine whether these novel mtDNA mutations in the tRNA genes are responsible for the defects in mitochondrial respiration function observed in these diseases. Cybrid clones (clones of rho zero HeLa cells with mtDNA from the patients) were isolated, and respiratory function and morphology of the mitochondria of the cybrid clones containing wild-type mtDNA and mutant mtDNA predominantly were compared. The results showed that accumulation of mutant mtDNA at 4269 alone without defects in the nuclear genome was sufficient to produce a disease phenotype, while mutant mtDNA at 10410 was not related to pathogenesis and reflected one of the rare polymorphic sites of human mtDNA. Moreover, we found that mitochondria in living cells were significantly swollen only when they contained predominantly the pathogenic mutant mtDNA, suggesting that the functional abnormality of mitochondria induced by pathogenic mtDNA mutations in tRNA genes is always associated with their swollen structure.

Transvaginal ultrasound imaging, histopathology and endocrinopathy in patients with polycystic ovarian syndrome

In order to investigate the pathological characteristics of polycystic ovaries diagnosed by transvaginal ultrasound (TVS) in patients with polycystic ovarian syndrome (PCOS) and to investigate the relationship between morphological and endocrine changes in the ovaries, 32 PCOS patients with bilateral polycystic ovaries (> 10 cysts) detected by TVS were studied; 20 ovulatory women served as controls. Ovarian tissues from wedge resection were examined histologically. A comparative histological and TVS study of ovarian morphology was made, and the relationship between the number of small cysts and the endocrine profile was examined. The position and size of small cysts on TVS agreed with those observed histologically. There was a significant correlation between the number of small cysts on TVS and the number of atretic follicles with hypertrophied and luteinized inner theca cells, and thickened ovarian capsules. Numerous atretic follicles and thickened ovarian capsules were observed in 97 and 64% of ovaries respectively, from PCOS patients. In patients with PCOS, a significant positive correlation was noted both between the number of small cysts and delta 4-androstenedione (ASD), and between ASD and the luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio. Furthermore, testosterone, ASD and the number of small cysts on TVS were significantly higher in PCOS patients with ovarian thickened tunica compared to PCOS patients without ovarian thickened tunica. TVS images of ovaries in patients with PCOS correlated with the histopathological and endocrine features. It is suggested that an increase in intra-ovarian small cysts leads to increased production of ovarian androgen, in turn influencing the secretion of gonadotrophin, and is correlated with ovarian capsular thickness.

Delayed myelination in a patient with 18q- syndrome

A Japanese boy with the typical manifestations of 18q-syndrome and delayed myelination on magnetic resonance imaging is described. Cytogenetic investigation revealed a deletion at 18q21.3. Three serial magnetic resonance images demonstrated that myelination in the central nervous system was delayed except for the corpus callosum and brainstem. This pattern of delayed myelination appears to be peculiar to the 18q- syndrome. Because the gene for myelin basic protein has been localized to the distal end of the long arm of chromosome 18, we speculate that the abnormal myelination in our patient was partly due to the failure of expression of the myelin basic protein gene.

Human herpesvirus 7: another causal agent for roseola (exanthem subitum)

Human herpesvirus 7 (HHV-7) was isolated from peripheral blood mononuclear cells of two infants with typical exanthem subitum. The HindIII-, BamHI-, and EcoRI-digested DNA patterns of the isolated viruses were very similar to that of the prototype HHV-7 (RK strain), but different from that of human herpesvirus 6 (HHV-6). During the convalescent period of the first patient, the titer of antibody to HHV-7 rose from < 1:10 to 1:320 by an immunofluorescence antibody test, whereas the titer of antibody to HHV-6 remained < 1:10. In the second patient, who had two independent episodes of exanthem subitum during 2 months, both HHV-6 and HHV-7 were sequentially isolated; seroconversion to HHV-6 occurred during the first episode and to HHV-7 during the second episode. In addition, sera from another 15 children who had episodes of exanthem subitum were serologically tested for antibodies to HHV-6 and HHV-7 by immunofluorescence antibody test. Five of seven patients had seroconversion to HHV-7 just after having typical signs and symptoms of exanthem subitum. These results suggest that HHV-7 is one of the causative agents of exanthem subitum.

Low frequency of the p53 gene mutations in neuroblastoma

BACKGROUND

The p53 gene frequently is affected by point mutations, rearrangements, or deletions that contribute to the genesis or progression of a wide variety of human adult solid tumors; however, to the authors' knowledge, this gene alteration has not been analyzed in neuroblastoma.

METHODS

Genomic DNA samples from 20 children with neuroblastoma, including 16 patients with advanced disease, were screened for the presence of mutations in exons 5-9 of the p53 gene, where over 90% of mutations have been reported to be located in human cancer. The screening technique employed polymerase chain reaction/single-strand conformation polymorphism analysis followed by direct DNA sequencing.

RESULTS

Heterozygous mutations were detected in 2 of the 20 cases. A silent mutation (T to G transversion) at codon 172 and a missense mutation (G to T transversion) at codon 259 were found in patients with Stage II and Stage IV disease, respectively. Thus, p53 mutations were found to occur in neuroblastoma, but at a low frequency (2 of 20).

CONCLUSIONS

Our data suggest that in a minority of neuroblastomas, p53 gene mutations may play a contributing role in tumorigenesis, but other genes presumably play a major role in this tumor.

[Cytological features and prognosis of megakaryoblastic leukemia]

Nine patients with acute leukemia showing 10% or more positive blast cells with platelet peroxidase (PPO) or CD41b were diagnosed as megakaryoblastic leukemia. Three patients transformed from myelodysplastic syndromes or myeloproliferative disorders. The PPO positivity ranged from 7 to 55% (median 45%), and that for CD41b was 1.6 to 67.0% (median 16.4%). Because electron microscopic myeloperoxidase or glycophorin A were also positive in some patients, and also because CD41b positivity was often discordantly lower than PPO positivity, a possibility of mixed leukemia demonstrating myeloid or erythroid differentiation was suggested in 6 of these cases. As for the treatment results, all 3 pediatric cases who received combination chemotherapy achieved complete remission (CR). Among 6 adult cases CR was obtained in only one patient to whom low-dose cytosine arabinoside was administered. The remaining adult patients who received combination chemotherapy died relatively early.

Syalil-SSEA1(SLX) levels in supernatant of cultured human lung carcinoma cell lines

SLX levels in the culture supernatant of the following 50 cell lines were measured by RIA: pulmonary carcinoma cell lines derived from 46 patients, cell lines of other human cancers derived from 4 patients, and 2 passaged human fibroblast cells as control. Of the 46 pulmonary carcinoma cell lines, 17 (37%) were SLX positive. When the SLX-positive rate was analyzed in relation to the histological type of pulmonary carcinoma, the positive rate was 71% (10/14) for adenocarcinoma, 27% (3/11) for squamous cell carcinoma, 33% (2/6) for large cell carcinoma, 0% (0/11) for small cell carcinoma and 50% (2/4) for adenosquamous cell carcinoma. Analysis of the relationship between tumor cell proliferation and SLX level in 20 patients revealed that the SLX level in the supernatant of SLX-producing cell lines becomes higher in proportion to the increase in the number of these cells. The SLX-positive rate did not differ significantly among different stages of pulmonary carcinoma at the time of tissue collection. There was no significant correlation between SLX production and prognosis. SLX production by each cell line was not correlated with the doubling time of the same cell line in vitro or in vivo (in nude mice). SLX production also showed no correlation with the duration of tumor cell passage.

Physicochemical damage to liposomal membrane induced by iron- or copper-mediated lipid peroxidation

A carboxyfluorescein (CF)-enveloping soybean phosphatidylcholine liposome was used as a model of physicochemical damage of biomembranes. The liposomes were exposed to a metal-chelate complex [2 mM of ferric nitrilotriacetate (FeNTA) or cupric nitrilotriacetate (CuNTA)] plus a reductant (2 mM of ascorbate or various concentrations of reduced glutathione), and CF release from damaged liposomal membranes and the generation of thiobarbituric acid-reactive substances (TBARS) were measured. In the presence of a reducing agent, both FeNTA and CuNTA stimulated markedly CF release and an increase in the TBARS level, while in the absence of a reducing agent both of the chelate complexes showed little CF release and TBARS. The effects of H2O2 addition to the reaction system containing liposome with FeNTA or CuNTA plus ascorbate were also examined. The CF release was slightly increased by the addition of a smaller dose (0.5 mM) of H2O2 and it was inhibited by 8 mM of H2O2. A similar result was obtained in the TBARS test. These results suggest that FeNTA- or CuNTA-mediated lipid peroxidation can damage liposomal membranes physicochemically, and the redox reaction of the chelated metal itself is more important than a Fenton-type reaction in the process.

Refined mapping of eight cosmid markers on human chromosome 22

Eight cosmid clones were regionally assigned to small subregions of chromosome 22 by hybridization with a total of 22 somatic cell hybrids. One cosmid was localized to the proximal part of 22q which contained the region commonly deleted in the DiGeorge syndrome. Seven cosmids showing restriction fragment length polymorphisms were localized to the telomeric region distal to the MB locus, which was reported to be frequently deleted in sporadic meningioma. These cosmids, when finely mapped and ordered, are considered useful for the identification of genetic alterations on this chromosome arm.

Central nervous system abnormalities in chromosome deletion at 11q23

Two Japanese pediatric patients with terminal deletion of the long arm of chromosome 11 are described. Both had the morphological abnormalities of the 11q deletion syndrome, such as prominent epicanthal folds, broad flat nasal bridge with short, upturned nose, short philtrum with carp-shaped mouth, cardiac anomalies and nonprogressive moderate psychomotor developmental delay. Patient 1 is the first case to be reported with 11q deletion with serial magnetic resonance (MR) examinations of cerebral white matter. The initial MR imaging studies demonstrated multiple areas of T1 and T2 prolongation in the cerebral white matter in both patients at the ages of 2 5/12 and 2 1/12 years, respectively. A second MR imaging, performed 1 year after the first in Patient 1, demonstrated slight improvement of the lesions. Neither patient showed clinical deterioration. These results suggest that the lesions were caused by delayed myelination, rather than by demyelination. It is suggested that an unknown factor which is important for myelination is located on the long arm of chromosome 11: perhaps the neural cell adhesion molecule (NCAM).

Predictive factors for postoperative recurrence of hepatocellular carcinoma

BACKGROUND/AIMS

The survival rate for hepatocellular carcinoma after hepatectomy remains unsatisfactorily low because of the high recurrence rate. The purpose of this study was to elucidate predictive factors for postoperative recurrence of hepatocellular carcinoma.

METHODS

Univariate analysis and a multiple regression model were used to retrospectively determine the factors potentially related to recurrence in 98 patients with hepatocellular carcinoma who had undergone curative hepatic resection.

RESULTS

DNA diploidy, absence of alcohol abuse, and absence of vascular invasion were determined to be independent favorable predictive factors using a multivariate analysis with Cox's proportional hazards model. A predictive index was developed using these three factors according to the following equation: 1.486 x (O = DNA diploidy or 1 = DNA aneuploidy) + 1.138 x (O = absence or 1 = presence of alcohol abuse) + 0.946 x (O = absence or 1 = presence of vascular invasion). This index was used to classify the patients into two groups with good or poor prognosis. The median time for disease recurrence for the two groups was 24.1 and 9.2 months, respectively (P < 0.001).

CONCLUSIONS

The results may be useful in the determination of treatment strategies and postoperative follow-up schedules and in the design and analysis of future clinical trials of therapy for hepatocellular carcinoma.

Comparison of chorionic villus sampling and amniocentesis: current status of prenatal diagnosis in Japan

Data were tabulated and compared for cases involving prenatal diagnostic procedures performed in the 8 years between January 1985 and December 1992. Of a total of 2781 pregnancies, 2546 cases (91.5 per cent) were diagnosed by amniocentesis, and 235 (8.5 per cent) by chorionic villus sampling (CVS). These findings reflect the fact that amniocentesis has taken deep root as the prenatal diagnostic procedure widely acknowledged by society, whereas even the existence of CVS has yet to be generally recognized. Analysis of our clinical and laboratory results and complication rates, however, suggests that CVS is a safe and accurate alternative to amniocentesis which should and can be positively presented to all patients who are candidates for prenatal diagnosis.

Positron emission tomography analysis of metastatic tumor cell trafficking

Organ-specific colonization of metastatic tumor cells is regulated through complex interactions of specific adhesion molecules on the tumor cell surface with organ specific microvascular endothelium. The present paper shows the real time tumor cell trafficking under the actual blood flow, which became able to be determined using a new technology, positron emission tomography. This technology would be useful to evaluate the interaction of characteristic tumor cells with various organs in vivo. High and low metastatic rat mammary adenocarcinoma cell variants, MTLn3 and MTC, respectively, were labeled with [2-18F]2-fluoro-2-deoxy-D-glucose in vitro. The labeled cells preferentially accumulated in the lungs, in which the disposition was more intense for MTLn3 than for MTC cells especially for the first 2-10 min after injection, apparently reflecting the organ specific interaction of metastatic tumor cells which may lead to metastasis. Such a short time change of cell disposition is easily determined in a living animal by this new technique. Furthermore, sialidase treatment of MTLn3 cells suppressed the accumulation of these cells in lungs, suggesting that some sialyl glycoconjugates on the MTLn3 cell surface play an important role in cell adhesion to lung endothelium. Positron emission tomography scanning thus enables the noninvasive study of the interaction of characteristic tumor cells with specific endothelium in a living animal.

Potential usage of thermosensitive liposomes for macromolecule delivery

Since transient swelling during phase transition of liposomes with hyper-osmotic internal aqueous phase may cause permeation of large molecules through the lipid bilayer, this type of liposomes can be useful for delivering macromolecules. In fact, thermosensitive liposomes containing an internal solution with osmotic pressure 2-fold higher than the physiologic level and sized through 200-nm pore, released encapsulated macromolecules such as dextran (M(r) 144,000) effectively when they were incubated at 40-42 degrees C. These liposomes were stable in the presence of serum compared to the liposomes with internal osmotic pressure more than 3-fold higher than the physiologic level.

MR diffusion imaging in Pelizaeus-Merzbacher disease

A case of classical type Pelizaeus-Merzbacher disease was reported. This patient exhibited marked motor and mental developmental delay, and nystagmus, with a positive familial history. Electrophysiological studies, such as on brainstem auditory evoked potentials, blink reflex and somatosensory evoked potentials, suggested marked disturbance of nerve conduction in CNS. T2-weighted magnetic resonance (MR) images revealed non-progressive diffuse T2 prolongation of cerebral white matter after a 2-year interval, indicating congenital hypomyelination in CNS. A newly developed magnetic resonance diffusion imaging method demonstrated the existence of diffusional anisotropy in the corpus callosum, internal capsule, and white matter of the frontal lobe. Although the diffusional anisotropy was considered to depend on the well-developed multiple layers of myelin around the axons, the imaging data of this patient demonstrated that the diffusional anisotropy did not necessarily depend on those multiple layers. These results may indicate the potential usefulness of MR diffusion imaging, combined with electrophysiological studies and conventional MR imaging, for analyzing the lesions of the cerebral white matter.

Ultrastructure and microvasculature of the parotid duct in the cat

Ultrastructure and microvascular pattern of the parotid duct (main excretory duct) in the cat were investigated by TEM and SEM. The duct was lined by a pseudostratified epithelium which was surrounded by a double-layered vascular sheath. Three kinds of principal cells were observed in this epithelium--tall columnar, light and basal cells. The tall columnar cells did not bear basement membrane specialization (infoldings) but well-developed lateral interdigitations. Microvilli were present on their luminal surface. Basal infoldings and lateral interdigitations did not develop in the light cells. Basal cells were located on the basement membrane of the epithelium. The basal surface of the duct epithelium was studded with half-desmosomes. The external sheath of the double-layered vascular sheath was composed of arterioles and venules, and the inner sheath was formed by a capillary network immediately beneath the epithelium. Meshes of the capillary network in the collecting ducts and the region of origin appeared round and in the superficial and deep regions became elongated along the duct axis. It can be concluded that the parotid duct in the cat not only transports the saliva into the oral cavity, but also actively builds up the primary saliva to the final saliva, owing to absorptive and secretory functions which were made by an important contribution of the double-layered vascular sheath surrounding the whole length of the duct.

[Megaloblastic anemia due to folate deficiency associated with hereditary spherocytosis]

A 19 years old male admitted to our hospital with fever, abdominal pain in May 1991. Physical examination revealed anemia, jaundice and marked splenomegaly. Severe pancytopenia with macrocytic hyperchronic anemia was noted along with elevated LDH and reduced serum folate. Blood smear showed nucleated RBCs, but only few microspherocytes. Bone marrow showed erythroid hyperplasia with remarkable megaloblastic changes. Megaloblasts were negative for PAS stain. Chromosome analysis revealed normal karyotype. Erythroleukemia was suspected initially, but his general condition as well as hematological data improved following 10 units of RBC transfusion. Following brief folic acid supplements, numerous microspherocytes became evident, typical osmotic fragility test revealed a pattern for hereditary spherocytosis. These observations led us to the diagnosis of hereditary spherocytosis complicated by megaloblastic anemia due to folate deficiency. As he developed folate deficiency again 10 months later, splenectomy were performed. The anemia improved after splenectomy.

Accuracy of computed tomography in determining pancreatic cancer tumor size

We compared tumor sizes determined by computed tomography (CT) with those of the resected specimens in 26 patients with pancreatic cancer in order to clarify whether or not the size of a pancreatic tumor can be accurately determined by CT. From the precontrast, postcontrast and arterial dominant phases of dynamic CT, the arterial dominant phase was found to yield the highest correlation between CT measured tumor size and that of the resected specimens (P < 0.01). The correlation coefficient was, however, not high (r = 0.67). CT alone may therefore be insufficient to determine tumor size in pancreatic cancer accurately.

[Experience with surgery for metachronous double cancer originated from thymus and lung]

A case with thymic cancer who developed pulmonary cancer ten years after the initial surgery was reported. A 50-year-old man was admitted to our hospital due to SVC syndrome. Chest X-ray examinations including venogram showed a mass lesion at the superior mediastinum. The patient underwent surgical removal and reconstruction of SVC, followed by radio-chemotherapy. The histologic diagnosis was thymic squamous cell carcinoma. He was admitted to our hospital again ten years after the initial surgery under the diagnosis of pneumonia. Bronchoscopic examination revealed nodular lesions at the right upper lobe bronchus and lower lobe bronchus, those lesions were diagnosed with squamous cell carcinomas cytologically. Right pneumonectomy was performed and the diagnosis was confirmed pathologically. Postoperative course was uneventful as of 10 months after the operation. It was concluded that this case showed metachronous double cancer of the thymus and the lung, as well as synchronous multiple bronchogenic carcinomas, which, to our knowledge, has never been reported yet.

[Sustained-release effect of the direct compressed tablet based on chitosan and Na alginate]

In the dissolution test of tablets prepared by the direct compression of chitosan with 10% sodium alginate (NaAlg), the release of theophylline was extended independently of the medium pH. The drug release mechanism of the tablet was investigated by measuring the dissolution behavior of such excipients as chitosan and NaAlg. It was shown that at the lower pH the drug release was accompanied with the dissolution of chitosan, while at the neutral pH it was controlled by the gelation and dissolution of NaAlg. Further more by the oral administration of the tablet to beagle dogs, the sustained release of theophylline was also confirmed by some bioavailability parameters. Thus the chitosan tablet with 10% NaAlg was expected to be a pH-independent sustained release dosage form.