Dosimetric Evaluation of Targets and Organs at Risk in Dose Escalation Study for Total Marrow and Lymphoid Irradiation

PURPOSE/OBJECTIVE(S)

Total marrow and lymphoid irradiation (TMLI) delivers radiation dose to the bone marrow and lymph nodal region while reducing the dose to non-target organs. We conducted a dose-escalation study of TMLI to improve treatment outcomes while reducing OAR doses using intensity-modulated radiation therapy. However, this dose escalation strategy may cause increasing risk of recurrence and adverse events because of dose uniformity compromises of the target. We hypothesized that the homogeneity index (HI) could become worse with increased target's dose while maintaining reduced OAR doses for the nine patients enrolled in the TMLI phase Ⅰ clinical trial.

MATERIALS/METHODS

Nine patients treated with TMLI using a treatment delivery system from September 2019 to August 2021 were included. The prescribed doses were 14 Gy/6 fr, 16 Gy/6 fr, and 18 Gy/6 fr twice daily for 3 days, with three patients allocated each prescription. Bone marrow, lymph nodal region, spleen, testis, brain, and liver were designated as targets. The bone marrow was divided into eight parts (see Table); an individual PTV margin was added to each structure. We intended to deliver the D80% prescription dose for PTV. For the brain and liver, the prescribed dose was 12 Gy in consideration of function preservation. Lenses, oral cavity, parotid glands, lungs, heart, esophagus, stomach, kidneys, intestines, and breasts were defined as OAR. Targets were evaluated with HI that was calculated using the formula HI = (D2%-D98%)/D50%, based on ICRU report 83. For OARs, Dmax, D2%, D10%, and mean dose constraint were evaluated.

RESULTS

The table lists HI for the PTV_ALL and each target. The HI of PTV_ALL rose with increasing prescription dose and was highest at 18 Gy. The highest HI was 0.632 for PTV_Rib at 18 Gy, and the lowest HI was 0.045 for PTV_testis at 14 Gy. OAR Dose constraints were achieved in all patients. The average OAR doses in all cases for lenses, oral cavity, parotid glands, lungs, heart, esophagus, intestines, kidneys, and breast were 4.7±0.80, 4.4±0.51, 6.7±0.48, 7.6±0.22, 7.8±0.19, 6.7±0.18, 7.4±1.12, 6.9±0.96, and 14.7 Gy, respectively. The Dmax of the lenes, D2% of the esophagus, and D10% of the stomach were 7.2 ± 1.09, 11.5 ± 0.47, and 10.9 ± 0.98 Gy, respectively.

CONCLUSION

In the TMLI phase I clinical trial, we evaluated the dose uniformity to the targets and the OAR dose constraints. Although the HI for PTV_ALL worsened with increasing prescription dose, compliance with OAR dose constraints was achieved in all patients.

An anti-ASCT2 monoclonal antibody suppresses gastric cancer growth by inducing oxidative stress and antibody dependent cellular toxicity in preclinical models

Glutamine is a major nutrient for cancer cells during rapid proliferation. Alanine-serine-cysteine (ASC) transporter 2 (ASCT2; SLC1A5) mediates glutamine uptake in a variety of cancer cells. We previously reported that KM8094, a novel anti-ASCT2 humanized monoclonal antibody, possesses anti-tumor efficacy in gastric cancer patient-derived xenografts. The aim of this study was to investigate the molecular mechanism underlying the effect of KM8094 and to further substantiate the preclinical feasibility of using KM8094 as a potential therapeutic agent against gastric cancer. First, ASCT2 was found to be highly expressed in cancer tissues derived from gastric cancer patients by an immunohistochemical analysis. Next, we performed in vitro studies using multiple gastric cancer cell lines and observed that several gastric cancer cells expressing ASCT2 showed glutamine-dependent cell growth, which was repressed by KM8094. We found that KM8094 inhibited the glutamine uptake, leading to the reduction of glutathione (GSH) level and the elevation of oxidative stress. KM8094 suppressed the cell cycle progression and increased the apoptosis. Furthermore, KM8094 exerted antibody dependent cellular cytotoxicity (ADCC) against human gastric cancer cells in vitro. Finally, in vivo studies revealed that KM8094 suppressed tumor growth in several gastric cancer xenografts. This effect was enhanced by docetaxel, one of the agents commonly used in gastric cancer therapy. Thus, our findings suggest that KM8094 is a potential new therapeutic agent for gastric cancer expressing ASCT2, which blocks the cellular glutamine metabolism and possesses ADCC activity.

Adult phenylketonuria presenting with subacute severe neurologic symptoms

We report a 48-year-old Japanese woman with phenylketonuria (PKU) who presented with severe neurological symptoms more than 30 years after discontinuation of dietary treatment. She was diagnosed with PKU at 6-years-old and was treated with a phenylalanine restricted diet until she was 15 years old. When she was 48-years-old she started having difficulty walking. After several months, she presented with severe disturbance of consciousness and was admitted. She was diagnosed as having neurological complications associated with PKU. We observed temporal changes in her laboratory data, brain MRI and single-photon emission computed tomography (SPECT) scan findings. Brain MRI on T2-weighted, fluid-attenuated inversion recovery and diffusion-weighted images revealed high intensity lesions in her bilateral frontal lobes and 123I-IMP SPECT showed marked and diffuse hypoperfusion in the bilateral cerebrum and cerebellum. After the resumption of dietary treatment, serum phenylalanine concentrations immediately decreased to the normal range. However, her neurological symptoms took longer to improve. We also found no clear temporal association between MRI findings and clinical severity. SPECT abnormalities showed marked improvement after treatment. It is well known that PKU patients who discontinue the dietary restriction from their childhood develop minor neurological impairments. However, PKU patients with late-onset severe neurological symptoms are very rare. To our knowledge, this is the first report regarding SPECT findings of PKU patients with late-onset severe neurological deterioration.

Extravillous trophoblast cell invasion is promoted by the CD44-hyaluronic acid interaction

INTRODUCTION

Extravillous trophoblast (EVT) cell invasion plays a crucial role in establishment of successful pregnancy. CD44, a cell-surface receptor for hyaluronic acid (HA), plays a key role in HA-mediated remodeling and degradation that triggers cancer cell invasion. However, few studies have reported on the expression or functions of CD44 in human EVT cells. We hypothesized that CD44-HA interaction was involved in invasion by EVT cells.

METHODS

To test our hypothesis, we conducted in situ examinations of CD44 and HA expression in the human first-trimester placenta. We also assessed the methylation status of CD44 promoter and exon 1 regions in EVT cells. Finally, we conducted transwell cell invasion assays using EVT cell lines and EVT cells isolated from first-trimester human villous explant cultures.

RESULTS AND DISCUSSION

EVT cells, but not villous trophoblast cells, in the first-trimester placenta expressed CD44. HA was strongly expressed in adventitia surrounding the spiral uterine arterial walls of the decidua. The extent of demethylation of CD44 promoter and exon 1 CpG islands was increased in EVT cells compared to those of first-trimester chorionic villi (including villous trophoblast cells), suggesting that CD44 expression was, at least in part, associated with methylation status. Data from transwell cell invasion assay with siRNA knockdown of CD44 revealed that CD44 expression significantly promoted invasion by EVT cells in an HA-dependent manner.

CONCLUSIONS

The discovery of a CD44-HA interaction between EVT cells and the extracellular matrix contributes to our understanding of the mechanism underlying invasion by EVT cells.

Ecological and genetic analyses of the complete genomes of Culex flavivirus strains isolated from Culex tritaeniorhynchus and Culex pipiens (Diptera: Culicidae) group mosquitoes

Culex flavivirus (CxFV) is an insect-specific flavivirus that was first reported in 2007 in Japan. CxFV strains were isolated from Culex tritaeniorhynchus Giles and Culex pipiens L. group mosquitoes and genetically characterized in Toyama Prefecture, Japan, from 2004 to 2009, to reveal host specificity, mode of transmission, and seasonal and geographical distribution. The minimum infection rate (MIR) of CxFV within Cx. tritaeniorhynchus populations was 0.3 and much lower than that within Cx. pipiens group (17.9). The complete genome sequences of 11 CxFV isolates (four from Cx. tritaeniorhynchus and seven from Cx. pipiens group) consisted of 10,835-10,837 nucleotides. When these 11 isolates and five reference strains (NIID-21-2 and Tokyo strains from Japan, Iowa07 and HOU24518 strains from the United States, H0901 strain from China) were compared, there were 95.2-99.2% nucleotide and 98.1-99.8% amino acid identities. Phylogenetic analysis showed that the 11 isolates were divided into four clusters. One cluster consisted of five isolates from Cx. pipiens group and Cx. tritaeniorhynchus from one site and their nucleotide sequences almost completely matched. One cluster consisted of an isolate with a unique sequence from a Cx. pipiens group mosquito captured in an aircraft from Taiwan, suggesting that it was introduced from abroad. CxFV strains were divided into several groups according to countries when nucleotide sequences of CxFV available in GenBank and 11 Toyama isolates were compared. These results suggest that CxFV is maintained in nature among Culex mosquitoes in a mosquito habitat-specific but not a species-specific manner.

IFPA Meeting 2012 Workshop Report I: comparative placentation and animal models, advanced techniques in placental histopathology, human pluripotent stem cells as a model for trophoblast differentiation

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, three of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of models and technical issues involved in placenta research: 1) comparative placentation and animal models; 2) advanced techniques in placental histopathology; 3) human pluripotent stem cells as a model for trophoblast differentiation.

Relationship between altered expression levels of MIR21, MIR143, MIR145, and MIR205 and clinicopathologic features of esophageal squamous cell carcinoma

In spite of the undisputed importance of altered expression patterns of microRNAs (miRNAs) in various cancers, there is little information on the clinicopathologic significance of cancer-related miRNAs (MIR21, MIR143, MIR144, MIR145, and MIR205) in esophageal squamous cell carcinoma (ESCC). We examined the expression levels of the precursor and mature miRNA genes in ESCC using real-time polymerase chain reaction (PCR). We also investigated the mRNA expression levels of processing elements (RNASEN, DGCR8, and DICER1) that participate in miRNA-biogenesis pathway. Furthermore, we analyzed the relationships between the expression levels of these five miRNAs and the clinicopathologic parameters of ESCC patients. The expression levels of mature MIR21 and mature MIR145 were higher in ESCC than those in normal epithelium (P < 0.05). The mature/pre ratio of MIR21 in ESCC was higher than that in normal epithelium (P < 0.05). With regard to miRNA-processing elements, the expression level of RNASEN was higher in ESCC than in normal epithelium (P < 0.05). Furthermore, altered expression of these miRNAs was related to the clinicopathologic features of ESCC patients. The high expression of mature MIR21 and mature MIR205 was associated with lymph node positivity in ESCC patients (P < 0.05). The high levels of expression of mature MIR143 and mature MIR145 were associated with recurrence of metastasis in ESCC patients (P < 0.05). The findings may imply that miRNA biogenesis is aberrantly accelerated in ESCC. Analysis of the expression levels of miRNAs should provide useful information for evaluation of the staging, prognosis, and treatment of ESCC patients.

Synthetic studies on selective adenosine A2A receptor antagonists. Part II: synthesis and structure-activity relationships of novel benzofuran derivatives

Based on the previously reported lead compound, a series of benzofuran derivatives were prepared to study their antagonistic activities to A(2A) receptor. The replacement of the phenyl group at the 4-position with a heterocyclic ring improved the PK profile and aqueous solubility. From these studies, we discovered a potent new A(2A) antagonist, 12a, which has both a good oral bioavailability and in vivo efficacy on motor disability in MPTP-treated common marmosets.

Correlative fluorescence and electron microscopy in tissues: immunocytochemistry

Correlative microscopy is a collection of procedures that rely upon two or more imaging modalities to examine the same specimen. The imaging modalities employed should each provide unique information and the combined correlative data should be more information rich than that obtained by any of the imaging methods alone. Currently the most common form of correlative microscopy combines fluorescence and electron microscopy. While much of the correlative microscopy in the literature is derived from studies of model cell culture systems we have focused, primarily, on correlative microscopy in tissue samples. The use of tissue, particularly human tissue, may add constraints not encountered in cell culture systems. Ultrathin cryosections, typically used for immunoelectron microscopy, have served as the substrate for correlative fluorescence and electron microscopic immunolocalization in our studies. In this work, we have employed the bifunctional reporter FluoroNanogold. This labeling reagent contains both a fluorochrome and a gold-cluster compound and can be imaged by sequential fluorescence and electron microscopy. This approach permits the examination of exactly the same sub-cellular structures in both fluorescence and electron microscopy with a high level of spatial resolution.

Rapid and simple detection of Clostridium botulinum types A and B by loop-mediated isothermal amplification

AIMS

To develop a convenient and rapid detection method for toxigenic Clostridium botulinum types A and B using a loop-mediated isothermal amplification (LAMP) method.

METHODS AND RESULTS

The LAMP primer sets for the type A or B botulinum neurotoxin gene, BoNT/A or BoNT/B, were designed. To determine the specificity of the LAMP assay, a total of 14 C. botulinum strains and 17 other Clostridium strains were tested. The assays for the BoNT/A or BoNT/B gene detected only type A or B C. botulinum strains, respectively, but not other types of C. botulinum or strains of other Clostridium species. Using purified chromosomal DNA, the sensitivity of LAMP for the BoNT/A or BoNT/B gene was 1 pg or 10 pg of DNA per assay, respectively. The assay times needed to detect 1 ng of DNA were only 23 and 22 min for types A and B, respectively. In food samples, the detection limit per reaction was one cell for type A and 10 cells for type B.

CONCLUSIONS

The LAMP is a sensitive, specific and rapid detection method for C. botulinum types A and B.

SIGNIFICANCE AND IMPACT OF THE STUDY

The LAMP assay would be useful for detection of C. botulinum in environmental samples.

The long-term outcome of high tibial osteotomy: a ten- to 20-year follow-up

We carried out a prospective study of 132 patients (159 knees) who underwent closed-wedge high tibial osteotomy for severe medial compartment osteoarthritis between 1988 and 1997. A total of 94 patients (118 knees) was available for review at a mean of 16.4 years (16 to 20). Seven patients (7.4%) (11 knees) required conversion to total knee replacement. Kaplan-Meier survival was 97.6% (95% confidence interval 95.0 to 100) at ten years and 90.4% (95% confidence interval 84.1 to 96.7) at 15 years. Excellent and good results as assessed by the Hospital for Special Surgery knee score were achieved in 87 knees (73.7%). A pre-operative body mass index > 27.5 kg/m(2) and range of movement < 100 degrees were risk factors predicting early failure. Although our long-term results were satisfactory, strict indications for osteotomy are required if long-term survival is required.

Proteomics of the human placenta: promises and realities

Proteomics is an area of study that sets as its ultimate goal the global analysis of all of the proteins expressed in a biological system of interest. However, technical limitations currently hamper proteome-wide analyses of complex systems. In a more practical sense, a desired outcome of proteomics research is the translation of large protein data sets into formats that provide meaningful information regarding clinical conditions (e.g., biomarkers to serve as diagnostic and/or prognostic indicators of disease). Herein, we discuss placental proteomics by describing existing studies, pointing out their strengths and weaknesses. In so doing, we strive to inform investigators interested in this area of research about the current gap between hyperbolic promises and realities. Additionally, we discuss the utility of proteomics in discovery-based research, particularly as regards the capacity to unearth novel insights into placental biology. Importantly, when considering under studied systems such as the human placenta and diseases associated with abnormalities in placental function, proteomics can serve as a robust 'shortcut' to obtaining information unlikely to be garnered using traditional approaches.

Endothelial Expression of Fc Gamma Receptor IIb in the Full-term Human Placenta

In the third trimester, human placental endothelial cells express Fc gamma receptor IIb (FcgammaRIIb). This expression is unique because FcgammaRIIb is generally expressed on immune cells and is typically undetectable in adult endothelial cells. Recently, we found a novel FcgammaRIIb-defined, IgG-containing organelle in placental endothelial cells; this organelle may be a key structure for the transcytosis of IgG across the endothelial layer. In this study, we verify the expression of FcgammaRIIb in endothelial placenta cells and use reverse transcriptase-polymerase chain reaction (RT-PCR) and sequencing analyses to define the expressed FCGR2B mRNA transcript variant. We also investigated the distribution of FCGR2B mRNA and protein within the vascular tree of the full-term human placenta by RT-PCR and quantitative microscopy. The mRNA sequence of FCGR2B expressed specifically in placental endothelial cells is that of transcript variant 2. FcgammaRIIb expression and synthesis occur throughout the placental vascular tree but do not extend into the umbilical cord. This study provides additional information on FcgammaRIIb expression in the human placenta.

Intracranial angiosarcoma arising from a schwannoma

Angiosarcomas rarely arise from schwannomas, but we describe here a case of angiosarcoma that arose from a remnant of a benign vestibular schwannoma that had been removed 10 years earlier. The patient was a 66-year-old man with no sign of neurofibromatosis. Although we attempted surgical resection, we could not totally remove the tumour. The patient died nine months after diagnosis, primarily as result of an abscess in the cerebellum and base of the skull. The histological diagnosis was confirmed by the immunohistochemical findings of positivity for CD34 antigen and S-100 protein in the resected tumour.A review of the literature revealed four other cases of angiosarcoma with schwannoma, all of which arose from an extracranial nerve. The present case is the first report of an angiosarcoma with schwannoma arising from an intracranial locus.

Application of boron-entrapped stealth liposomes to inhibition of growth of tumour cells in the in vivo boron neutron-capture therapy model

Tumour cell destruction in boron neutron-capture therapy (BNCT) is due to the nuclear reaction between (10)B and thermal neutrons. It is necessary for effective BNCT therapy to accumulate (10)B atoms in the tumour cells. The delivery system consisted of polyethylene-glycol (PEG) binding liposomes (DPPC/cholesterol/DSPC-PEG2000) with an entrapped (10)B-compound and we evaluated the cytotoxic effects of intravenously injected (10)B-PEG-liposomes on human pancreatic carcinoma xenografts in nude mice with thermal neutron irradiation. After thermal neutron irradiation of mice injected with (10)B-PEG-liposomes, growth of AsPC-1 tumours was suppressed relative to controls. Injection of (10)B-PEG-liposomes caused the greatest tumour suppression with thermal neutron irradiation in vivo. These results suggest that intravenous injection of (10)B-PEG-liposomes can increase the retention of (10)B atoms by tumour cells, causing suppression of tumour growth in vivo, after thermal neutron irradiation.

Promotion of Thyroid Carcinogenesis by para-aminobenzoic Acid in Rats Initiated with N-bis(2-hydroxypropyl)nitrosamine

Sulfonamide analogues of para-aminobenzoic acid (PABA), a precursor of folate synthesis, have beneficial effects as antifolate, but thyroid peroxidase inhibition has been reported as a side effect that results in promotion of rat thyroid carcinogenesis. In the present study, effects of PABA itself on F344 rat thyroid carcinogenesis after initiation with N-bis(2-hydroxypropyl)nitrosamine (DHPN) were evaluated. In experiment 1, rats in groups 1-4 received a single subcutaneous injection of DHPN at 2800 mg/kg, and groups 5 and 6 received vehicle saline alone. From 1 week after DHPN initiation, rats in groups 2, 3, 4, and 6 were fed basal diet containing 0.25%, 0.5%, 1.0%, and 1.0% PABA, respectively, for 40 weeks. Rats in groups 1 and 5 received basal diet alone throughout the experiment. The final incidence of thyroid follicular cell adenomas and adenocarcinomas was significantly (p < 0.05 or 0.01) increased in groups 3 and 4 as compared to group 1. No thyroid tumors were found in groups 5 and 6. In experiment 2, animals in group 1 were fed basal diet alone, while groups 2 and 3 were given 0.5% and 1.0% PABA in the diet, respectively, for 2 weeks. Thyroid weights in group 3, and serum thyroid stimulating hormone level and proliferative activity of follicular cells in groups 2 and 3 were significantly (p < 0.05 or 0.01) elevated. In addition, the serum thyroxine level in group 3 was significantly (p < 0.05) depressed. These results clearly indicate that PABA exerts promotion/progression effects on rat thyroid carcinogenesis as a result of hypothyroidism followed by negative-feedback via the thyroid-pituitary axis.

Localization of organic anion transporting polypeptide 3 (oatp3) in mouse brain parenchymal and capillary endothelial cells

Organic anion transporting polypeptide 3 (oatp3) transports various CNS-acting endogenous compounds, including thyroid hormones and prostaglandin E2, between extra- and intracellular spaces, suggesting a possible role in CNS function. The purpose of this study was to clarify the expression and localization of oatp3 in the mouse brain. RT-PCR analysis revealed that oatp3 mRNA is expressed in brain capillary-rich fraction, conditionally immortalized brain capillary endothelial cells, choroid plexus, brain and lung, but not in liver or kidney, where oatp1, 2 and 5 mRNAs were detected. Immunohistochemical analysis with anti-oatp3 antibody suggests that oatp3 protein is localized at the brush-border membrane of mouse choroid plexus epithelial cells. Furthermore, intense immunoreactivity was detected in neural cells in the border region between hypothalamus and thalamus, and in the olfactory bulb. Immunoreactivity was also detected in brain capillary endothelial cells in the cerebral cortex. These localizations in the mouse brain suggest that oatp3 plays roles in blood-brain and -cerebrospinal fluid barrier transport of organic anions and signal mediators, and in hormone uptake by neural cells.

Cathepsin D, but not cathepsin E, degrades desmosomes during epidermal desquamation

BACKGROUND

We previously reported that an ambient aspartic proteinase is crucial to desquamation of the stratum corneum at pH 5. Identification of this aspartic proteinase by using enzyme inhibitors suggested it to be cathepsin D, although we could not exclude cathepsin E.

OBJECTIVES

To determine the identity of this aspartic proteinase and its distribution within the stratum corneum.

METHODS

We measured enzyme activities of cathepsin D and cathepsin E in the salt and detergent extracts from callus stratum corneum, using a fluorogenic peptide as a substrate and comparing the effect of addition of Ascaris pepsin inhibitor (specific for cathepsin E) with that of pepstatin A (which inhibits both cathepsin D and cathepsin E). Both enzymes were then extracted and purified from plantar stratum corneum samples and identified by Western blotting. Immunofluorescence microscopy was used to investigate the localization of proteinases within human plantar stratum corneum sample sections.

RESULTS

We found that 20% of total aspartic proteinase activity could be attributed to cathepsin E, the remainder to cathepsin D. Two subunits of cathepsin D were identified, a mature active form at 33 kDa and an intermediate active form at 48 kDa; cathepsin E was also identified at 48 kDa, although in a stained band 10-fold weaker in the immunoblot. Immunofluorescence microscopy showed the antibody to cathepsin D to be localized in the lipid envelopes of the stratum corneum, whereas that to cathepsin E stained the tissue diffusely. The labelling for cathepsin D was similar to that observed for desmosomes, and immunoelectron microscopy confirmed that cathepsin D was present on desmosomes. On the other hand, cathepsin E occurred intracellularly within the squames.

CONCLUSIONS

We conclude that cathepsin D, and not cathepsin E, causes desquamation by degrading desmosomes.

Survival analysis of a cementless, cruciate-retaining total knee arthroplasty

We performed a prospective study of 54 patients (76 knees) who underwent Osteonics series 3000 cruciate-retaining cementless total knee arthroplasty between December 1990 and June 1993. Five patients (seven knees) were lost to follow-up (90.7% completion). One patient required revision at 10.5 years after operation.

The rate of survival was 100% at ten years and 96.7% at 13 years. The mean ten-year knee and function scores were 79 and 59 respectively. Both were significantly better than the pre-operative scores. The range of movement also improved. Although a radiolucent line around the tibial component enlarged in six knees (20.7%) at ten years, the clinical outcome was generally good. In a patient who died after 5.5 years, post-mortem examination of the knee showed no bony ingrowth into the tibial component. Despite poor bony ingrowth, press-fit fixation was satisfactory and good results can be obtained with this cementless, cruciate-retaining prosthesis.

Human amniotic epithelial cells are morphologically homogeneous: enzymehistochemical, tracer, and freeze-substitution fixation study

We examined the fine subcellular morphology of human amniotic epithelial cells and attempted to answer the question as to whether amniotic epithelial cells consist of heterogeneous or homogeneous cells, which has long been controversial. Study subjects were fetal membranes from pregnant women (n=18) who abdominally gave birth to healthy infants at term (37.9+/-0.7 weeks of gestation, mean+/-sd). The methods employed were transmission electron microscopy, enzymehistochemistry, tracer permeability analysis, and freeze-substitution fixation. The labelings for acid phosphatase, cytochrome c oxidase, and CA++ATPase were seen in the lysosomes, mitochondria, and lateral plasma membranes, respectively. The staining distribution pattern of these three enzymes and the morphology of the organelle highlighted by these enzymehistochemistry did not differ among cells. Freeze-substitution fixation revealed that intercellular spaces in the amniotic epithelial cells were narrower than previously thought, but the tracers (horse radish peroxidase and lanthanum nitrate) fully entered these spaces. There were no variations in the tracer permeability among cells. All cells from freeze-substitution fixation exhibited the same morphological features. From these morphological viewpoints, we conclude that human term amniotic epithelial cells consist of a homogeneous cell population.

PDX1 homeobox protein expression in pseudopyloric glands and gastric carcinomas

BACKGROUND AND AIMS

Although it has been reported that intestinal metaplasia implicated in gastric carcinogenesis is induced by the ParaHox gene CDX2, it is unclear which genes are responsible for the formation of pseudopyloric glands and whether they play a role in gastric carcinogenesis. Pancreatic-duodenal homeobox 1 (PDX1) is also a ParaHox gene which contributes to the genesis and development of the pancreas, duodenum, and antrum. To clarify its significance for the formation of pseudopyloric glands and gastric carcinogenesis, we investigated expression of PDX1 and mucin in gastric carcinomas and surrounding mucosa.

METHODS

Gastric carcinoma tissues from 95 patients were used for immunohistochemical analyses of PDX1, and mucins MUC6 and MUC5AC.

RESULTS

PDX1 was found to be frequently expressed in pseudopyloric glands and intestinal metaplasia. MUC6 was more abundant than MUC5AC in pseudopyloric glands while higher levels of MUC5AC than MUC6 were evident in intestinal metaplasia. The frequency of PDX1 positive reactivity was higher in differentiated type carcinomas (39/43, 90.7%) and T1 carcinomas (42/43, 97.7%) than in undifferentiated type (33/52, 63.5%) and T2-4 (30/52, 57.7%) carcinomas. PDX1 and MUC6 double positive expression was observed in carcinomas, respectively, including the corpus, and also correlated with histological type and depth of invasion. In contrast, no link was apparent between PDX1 and MUC5AC double positive reactivity and histological type.

CONCLUSION

Our study suggests that PDX1 plays an important role in the development of pseudopyloric glands, and that pseudopyloric glands may reflect a condition associated with gastric carcinogenesis.

Sequential analysis of testicular lesions and serum hormone levels in rats treated with a Psoralea corylifolia extract

In order to clarify pathogenetic targets for the testicular toxicity of a extract of Psoralea corylifolia (P. corylifolia), F344 rats were fed diet containing 3% P. corylifolia extract for up to 12 weeks and subjected to hormone assays and histopathological examination on the testis and epididymis at weeks 1, 2, 4, 8 and 12 (Exp 1). Similar analyses were performed on 1, 3, 7 and 14 days after a single gavage administration of the P. corylifolia extract at a dose of 10 g/kg b.w. (Exp 2). In Exp 1, increase in the numbers of degenerated and exfoliated germ cells and loss of elongated spermatids beyond steps 7 or 8 were initially observed in the seminiferous tubules at week 1, followed by more pronounced degeneration of germ cells with depletion of post-meiotic populations from week 2. The tubular degeneration was associated with Leydig cell atrophy and persistent reduction of serum testosterone and FSH levels throughout the treatment period and a slight reduction of serum LH in later stages. In Exp 2, reduction of serum testosterone and FSH levels preceded degeneration of germ cells in stage VII and VIII tubules at 3 and 7 days after the administration. The results suggest that rapid androgen deprivation reflecting direct interference with Leydig cell function and simultaneous disturbance of the pituitary-testicular axis play pivotal roles in P. corylifolia extract-induced germ cell injury in seminiferous tubules.

Demonstration of glucose-6-phosphate dehydrogenase in rat Kupffer cells by a newly-developed ultrastructural enzyme-cytochemistry

Although various tissue macrophages possess high glucose-6-phosphate dehydrogenase (G6PD) activity, which is reported to be closely associated with their phagocytotic/bactericidal function, the fine subcellular localization of this enzyme in liver resident macrophages (Kupffer cells) has not been determined. We have investigated the subcellular localization of G6PD in Kupffer cells in rat liver, using a newly developed enzyme-cytochemical (copper-ferrocyanide) method. Electron-dense precipitates indicating G6PD activity were clearly visible in the cytoplasm and on the cytosolic side of the endoplasmic reticulum of Kupffer cells. Cytochemical controls ensured specific detection of the enzymatic activity. Rat Kupffer cells abundantly possessed enzyme-cytochemically detectable G6PD activity. Kupffer cell G6PD may play a role in liver defense by delivering NADPH to NADPH-dependent enzymes. G6PD enzyme-cytochemistry may be a useful tool for the study of Kupffer cell functions.

Fixation of a hydroxyapatite-tricalcium phosphate-coated cementless knee prosthesis

Miller-Galante II total knee arthroplasty (MG II TKA) was performed on 32 knees in 30 patients. On both the femoral and tibial components, the fibre-metal area was plasma-sprayed with hydroxyapatite-tricalcium phosphate (HA-TCP). The clinical and radiographic outcome was evaluated. A mean pre-operative knee score of 26.0 ± 18.6 (SD) increased to 97.5 ± 3.5 and a mean pre-operative functional score of 21.7 ± 15.0 (SD) increased to 83.4 ± 12.4 at follow-up of seven years. Clear zones were common around the components at one month post-operatively but had completely disappeared after six months. An autopsy of a patient who underwent MG II TKA with HA-TCP two years previously, showed osteogenesis in all parts of the fibre-metal, and bone tissue comprised 77.7% of the interface. This coated prosthesis has good early fixation which is maintained at seven years with good clinical and radiographic outcomes.

Correlative microscopy of ultrathin cryosections is a powerful tool for placental research

In this report, we describe procedures for correlative fluorescence and electron microscopy in immunocytochemical studies on the human placenta. Ultrathin cryosections of placenta were used for detection of the distribution of antigens by immunofluorescence and subsequently by immunoelectron microscopy of the same ultrathin cryosection. This methodology has certain advantages over conventional immunohistochemistry and immunoelectron microscopy. The advantages are, most notably, that the same exact structures are examined by both imaging modalities. In addition, since the tissue is physically sectioned (50-100 nm thickness), greater resolution for fluorescence can be obtained in the z-dimension than can be obtained by optical sectioning in confocal microscopy. This last point is of particular importance for discriminating between structures closely stacked in the z-dimension. In this report, we have determined the distribution of caveolin-1 in ultrathin cryosections of terminal villi of the human term placenta. We demonstrate that the use of ultrathin cryosections is a powerful approach for immunofluorescence and correlative microscopy for the in situ localization of antigens.

Impaired Delta Np63 expression associates with reduced beta-catenin and aggressive phenotypes of urothelial neoplasms

p63, a homologue of the p53 gene, is considered to be essential for the normal development of stratified epithelia including urothelium. To examine possible roles of p63 in urothelial tumorigenesis, p63 expression was systematically examined in normal urothelium, low-grade papillary noninvasive (LPN) urothelial tumours, and high-grade or invasive carcinomas, using either an isoform-nonspecific or a Delta N-isoform-specific antibody. Expression profiles of p63 were also analysed in cultured cells. Immunoreactivity with the two antibodies was virtually identical in tissue samples examined. Basal and intermediate cell layers of normal urothelium showed intense nuclear p63 immunostaining. This normal staining pattern was preserved in a majority of LPN tumours, whereas it was frequently impaired in high-grade or muscle-invasive carcinomas. At the mRNA level, Delta Np63 expression predominated over TAp63, and amounts of Delta Np63 mRNA correlated with p63 immunoreactivity, confirming that Delta Np63 accounts for p63 expressed in urothelial tissues. In cultured cells, Delta Np63 was also expressed in low-grade tumour cells as well as normal urothelial cells, but undetectable in high-grade aggressive carcinoma cells. Interestingly, impaired Delta Np63 expression significantly associated with reduced beta-catenin expression that was possibly related to progression of urothelial neoplasms. Thus, impaired Delta Np63 expression characterises aggressive phenotypes of urothelial neoplasms.

In vitro study of the functional expression of organic anion transporting polypeptide 3 at rat choroid plexus epithelial cells and its involvement in the cerebrospinal fluid-to-blood transport of estrone-3-sulfate

The cerebrospinal fluid-to-blood efflux transport of estrone-3-sulfate (E(1)S) via the blood-cerebrospinal fluid barrier (BCSFB) may play an important role in regulating E(1)S levels in the brain. Here, we investigated the efflux transport of E(1)S at the BCSFB using conditionally immortalized rat choroid plexus epithelial cells (TR-CSFB) and identified the responsible transporter. The [(3)H]E(1)S uptake by TR-CSFB cells was composed of saturable and nonsaturable components, and the K(m) and V(max) values of the saturable component were determined to be 16.8 +/- 5.1 microM and 12.3 +/- 2.3 pmol/min/mg of protein, respectively. [(3)H]E(1)S uptake was inhibited by probenecid, cholate, taurocholate, sulfobromophthalein, dehydroepiandrosterone sulfate, triiodothyronine, thyroxin, and digoxin but not by p-aminohippuric acid, gamma-aminobutyric acid, or methotrexate, suggesting the involvement of organic anion transporting polypeptide (oatp) in the uptake. Reverse transcription-polymerase chain reaction analysis revealed that oatp3 was expressed in TR-CSFB cells and isolated rat choroid plexus, although oatp1 was not detected in either. Xenopus laevis oocytes expressing oatp3 exhibited [(3)H]E(1)S uptake activity with a K(m) of 8.09 +/- 2.83 microM and V(max) of 8.02 +/- 0.87 pmol/h/oocyte. Moreover, oatp3 is localized at the brush-border membrane of choroid plexus epithelial cells. These results suggest that oatp3 is involved in the E(1)S efflux transport at the BCSFB.

Differential diagnosis of atypical epithelium of biopsied gastric mucosa using immunostaining of Ki-67, p53, hMLH1 and MDM2 expression

Gastric biopsy specimens were classified from category 1 (C1) to C5 according to the Vienna classification of gastrointestinal epithelial neoplasia. Fifty cases of C1, 40 cases of C2, 29 cases of C3, 19 cases of C4-1, 20 cases of C4-2+3, and 24 cases of C5 were selected and the expression of Ki-67, p53, hMLH1, and MDM2 was examined immunohistochemically to obtain useful data for the differential diagnosis of controversial cases of C2 and C4. The C2 cases, which did not show definitive neoplasia, were divided into two groups: one group had regenerative epithelium showing a relatively high degree of atypia (regenerative atypia: RA) and the other had carcinoma showing a mild degree of atypia (carcinoma of low grade atypia: CLGA). There were 0/23 RA and 12/17 CLGA cases that were positive for p53. Ki-67-positive cells were localized in the mitotic cell zone in RA, whereas they were irregularly distributed in CLGA. None of the cases of high-grade adenoma (C4-1) showed p53 expression, whereas 19 out of 44 well-differentiated adenocarcinoma cases (C4-2+3 and C5) were positive for p53. Ki-67-positive cells were localized in the mitotic cell zone in C4-1, whereas they were irregularly distributed in C4-2+3. hMLH1 was expressed in the proliferative cell zone of the normal foveolae, in all of the cases of adenoma (C3, C4-1) and in most cases of adenocarcinoma (C4-2,3 and C5). However, in 3 cases of C4-2+3, which showed a relatively mild degree of cellular atypia and were difficult to differentiate from high-grade adenoma (C4-1), the neoplastic cells were completely negative for hMLH1. MDM2 showed no characteristic expression in any gastric lesion. In conclusion, p53-positive cases of C2 and C4 were highly suggestive of carcinoma. Even if the case was negative for p53, the irregular distribution pattern of Ki-67-positive cells was highly suggestive of carcinoma. hMLH1-negativity in the C4 cases is strongly suggestive of carcinoma and this may be an useful marker for differentiating C4-2+3 from C4-1.

Histopathological diagnosis of biopsy samples from early esophageal carcinoma

Carcinoma of the esophagus is frequently diagnosed in advanced clinical stages. When an esophagic carcinoma has infiltrated the submucosa or the muscular or serosa, metastases are a common finding. Thus, early diagnosis and opportune treatment are vital for patients with this type of neoplasm. Timely diagnosis can be done through endoscopic or X-ray studies and confirmed through a histopathological study by directed biopsy. We presently report the case of a 65 year old man with precedents of achalasia who underwent an endoscopic study using the Lugol staining technique for suspected malignant lesion classified as 0-IIc. After two biopsies it was diagnosed as early carcinoma of the esophagus and was subjected to mucosectomy. Histopathological findings are reviewed at architectural and cellular level and are essential to establish the diagnosis of early neoplastic lesions of the esophagus epithelium. These cellular changes are corroborated by immunohistochemical studies with nuclear expression of p53. The relevant literature was reviewed and experiences by Japanese and North American pathologists compared with emphasis on the need for multidisciplinary management to make an early diagnosis by endoscopic studies, Lugol staining, X-rays, biopsy and conservative treatment based on mucosectomy.

Sensitivity of biopsy site in evaluating regression of gastric atrophy after Helicobacter pylori eradication treatment

BACKGROUND

Helicobacter pylori infection is a major cause of the progress of gastric glandular atrophy, a high-risk background factor in the development of gastric cancer. Regression of gastric atrophy is critical to prevention of cancer by H. pylori eradication treatment. However, it is controversial whether gastric atrophy regresses after H. pylori eradication.

AIM

To determine the most sensitive and appropriate biopsy site for evaluation of regression of atrophy after treatment.

SUBJECTS AND METHODS

Thirty-eight patients who showed regression of gastric atrophy in histology after treatment were investigated. Four biopsy specimens from the lesser and greater curvatures in the antrum and corpus were evaluated before and after treatment according to the Updated Sydney System.

RESULTS

Regression of atrophy after treatment was seen in 30 of 38 biopsy specimens from the lesser curvature of the corpus (79%), and this site was most sensitive. Odds ratio of this site to the others was 8.28. Regression of atrophy in this site was observed at 12.2 months in the younger patients and 15.9 months in the elder patients.

CONCLUSION

Biopsy sampling from the lesser curvature of the corpus is the most sensitive and appropriate for evaluation of regression of gastric atrophy after H. pylori eradication treatment.

Gastric mucosal density of Helicobacter pylori estimated by real-time PCR compared with results of urea breath test and histological grading

The accuracy of the urea breath test (UBT) and histological grading for estimation of the density of Helicobacter pylori in gastric mucosa is not known. Real-time (TaqMan) PCR was used to estimate the total number of H. pylori genomes in biopsy samples. These values were compared with those obtained by the UBT and the histological grade obtained by the Sydney system. The UBT and endoscopy with antral and corporal biopsies were performed in 88 consecutive untreated patients with dyspepsia. Bacterial culture and the rapid urease test were done with fresh biopsy materials. TaqMan PCR and histological examination were done on serial paraffin sections of the biopsy samples. Of the five methods tested, TaqMan PCR had the highest sensitivity and specificity (both 100%) in the diagnosis of H. pylori infection. The mean density of H. pylori genomes for pairs of biopsy samples from individual patients was compared with the individual values obtained by the UBT; correlation between the results was significant. The density of H. pylori genomes was higher in histological grades 1, 2 and 3 than in grade 0, without significant differences between adjacent grades from 1 to 3. These results suggest that the severity of H. pylori infection of the stomach can be estimated by the UBT and that histopathologists might state whether the organism is present or absent, rather than making a quantitative statement as recommended in the Sydney system.

[A 90-day repeated dose oral toxicity study of magnesium chloride in F344 rats]

In order to examine the toxicity of magnesium chloride hexahydrate, four groups of 10 male and 10 female F344 rats received the compound by dietary supplementation at 2.5, 0.5, 0.1 or 0% for 90 days. No treatment-related death was observed during the study. Transient soft stool and sustained increase in water consumption were observed both in males and females of the 2.5% group and slight reduction in body weight gain was noted in the high-dose males. There were no toxic changes in food consumption, organ weights, hematology and biochemistry, and histopathological examinations in any treated-groups. Based on these results, the no-observed-adverse-effect-level was estimated to be 0.5%, and 2.5% is considered to be appropriate as highest dose for a 2-year carcinogenicity study.

Absorption and urinary excretion of (-)-epicatechin after administration of different levels of cocoa powder or (-)-epicatechin in rats

(-)-Epicatechin is a major polyphenol component of cocoa powder. The absorption and urinary excretion of (-)-epicatechin following administration of different levels of either cocoa powder (150, 750, and 1500 mg/kg) or (-)-epicatechin (1, 5, and 10 mg/kg) were evaluated in rats. Both the sum of plasma (-)-epicatechin metabolites at 1 h postadministration and peak plasma concentrations increased in a dose-dependent fashion. The sum of (-)-epicatechin metabolites in urine, excreted within 18 h postadministration, also increased with dose. Moreover, the sum of (-)-epicatechin metabolites excreted in urine reached the same level in both (-)-epicatechin and cocoa powder administration groups for equivalent amounts of (-)-epicatechin. These results suggest that, in the dose range examined in this study, bioavailability of (-)-epicatechin following administration of either (-)-epicatechin or cocoa powder shows dose dependence and that the various compounds present in cocoa powder have little effect on the bioavailability of (-)-epicatechin in cocoa powder.

Screening of the antibacterial effects of a variety of essential oils on respiratory tract pathogens, using a modified dilution assay method

The purpose of this study was to examine the antibacterial effects of a wide variety of essential oils on major respiratory tract pathogens. The antibacterial activity of 14 essential oils and their major components was evaluated by agar-plate dilution assay under sealed conditions, with agar used as a stabilizer for homogeneous dispersion. Of the selected strains of four major bacteria causing respiratory tract infection, Haemophilus influenzae was most susceptible to the essential oils, followed by Streptococcus pneumoniae and Streptococcus pyogenes. Staphylococcus aureus was less susceptible. No cross-resistance was observed between penicillin-sensitive and penicillin-resistant S. pneumoniae. Escherichia coli, used as a control bacterium, showed the lowest susceptibility. Essential oils containing aldehyde or phenol as a major component showed the highest antibacterial activity, followed by the essential oils containing terpene alcohols. Other essential oils, containing terpene ketone, or ether, had much weaker activity, and an oil containing terpene hydrocarbon was inactive. Based on these findings, thyme (wild, red, and geraniol types), cinnamon bark, lemongrass, perilla, and peppermint oils were selected for further evaluation of their effects on respiratory tract infection.

DNA methylation is a critical cell-intrinsic determinant of astrocyte differentiation in the fetal brain

Astrocyte differentiation, which occurs late in brain development, is largely dependent on the activation of a transcription factor, STAT3. We show that astrocytes, as judged by glial fibrillary acidic protein (GFAP) expression, never emerge from neuroepithelial cells on embryonic day (E) 11.5 even when STAT3 is activated, in contrast to E14.5 neuroepithelial cells. A CpG dinucleotide within a STAT3 binding element in the GFAP promoter is highly methylated in E11.5 neuroepithelial cells, but is demethylated in cells responsive to the STAT3 activation signal to express GFAP. This CpG methylation leads to inaccessibility of STAT3 to the binding element. We suggest that methylation of a cell type-specific gene promoter is a pivotal event in regulating lineage specification in the developing brain.

Anticlastogenic activity of cacao: inhibitory effect of cacao liquor polyphenols against mitomycin C-induced DNA damage

Oxidative DNA damage has been implicated as a factor playing a role in mutagenesis and carcinogenesis. We investigated the anticlastogenic activity of cacao: the inhibitory effect of cacao liquor polyphenols on DNA strand cleavage induced by mitomycin C (MMC) in vitro and the anticlastogenic effect of cacao liquor extract against formation of micronuclei induced by MMC in bone marrow cells and peripheral blood cells of mice. In the DNA strand cleavage test, cacao liquor polyphenols inhibited cleavage of RFI DNA. In the micronuclei test, the frequency of occurrence of micronucleated cells among bone marrow cells and peripheral blood cells were reduced significantly when cacao liquor extract was administered orally to mice 6 h before intraperitoneal injection of MMC. These findings suggest that cacao liquor polyphenols are effective in preventing DNA damage, and one of the mechanisms of action might involve scavenging of active oxygen radicals generated in reactions initiated by MMC.

Inhibition of BMP2-induced, TAK1 kinase-mediated neurite outgrowth by Smad6 and Smad7

BACKGROUND

BMP2 is known to play a wide variety of roles, including some in the development of the nervous system. This cytokine has been reported to induce neurite outgrowth in rat pheochromocytoma PC12 cells via the activation of a p38 MAP kinase, although its regulatory mechanism remains largely to be elucidated.

RESULTS

BMP2-induced neurite outgrowth in PC12 cells was inhibited by the introduction of a kinase-negative form of a MAP kinase kinase kinase, TAK1, an upstream regulatory kinase for p38 kinase. Following BMP2 stimulation, the expression of Smad6 and Smad7, inhibitory Smad species that are known to inhibit the BMP2-restricted Smad species, Smad1, Smad5 and Smad8, was up-regulated. Unexpectedly, over-expression of either Smad6 or Smad7 in PC12 cells repressed the BMP2-induced neurite outgrowth and severely impeded the p38 kinase pathway. Both of these inhibitory Smads were found to interact physically with TAK1-binding protein, a molecule required for TAK1 activation.

CONCLUSIONS

This study demonstrates that BMP2-induced neurite outgrowth in PC12 cells involves activation of the TAK1-p38 kinase pathway which is inhibited by Smad6 and Smad7.

Fate alteration of neuroepithelial cells from neurogenesis to astrocytogenesis by bone morphogenetic proteins

Bone morphogenetic proteins (BMPs), a class of cytokines belonging to the transforming growth factor-beta superfamily, have been shown to play a wide variety of roles during development including those in the central nervous system. We here report that BMP2, BMP4 and BMP7 have an equivalent potential to inhibit neurogenesis and concomitantly induce astrocytogenesis of mouse fetal neuroepithelial cells. We further show that these BMPs activate a promoter of the gene for negative helix-loop-helix (HLH) factor, Id1, which is known to inhibit the function of such neurogenic transcription factors as Mash1 and neurogenin. These results suggest that BMP2, BMP4 and BMP7 alternate the fate of neuroepithelial cells from neuronal type to astrocytic one via a common mechanism involving negative HLH factor.

Experimental small bowel transplantation using a newborn intestine in rats: IV. Effect of cold preservation on graft neovascularization

BACKGROUND/PURPOSE

University of Wisconsin (UW) solution is one of the most superior organ preservation solutions for liver, kidney, and pancreas; however, it still is controversial for intestinal preservation. Here, the authors studied the efficacy of preservation with 2 kinds of solutions, UW and modified TOM (m-TOM) solutions in our experimental newborn intestinal transplantation model. UW solution was used as a standard intracellular and m-TOM solution as an extracellular preservation solution. Lactated ringer (LR) solution was used as a control.

METHODS

Newborn intestine, which were preserved in these solutions for 24 or 48 hours, were transplanted in the subcutaneous spaces of the syngeneic recipients without surgical vascular anastomosis and histologically examined 14 days after grafting. The preserved grafts were evaluated histologically by use of light and electron microscopy just after preservation. The biochemical parameters such as LDH and serotonin also were measured in the supernatants of preservation solutions.

RESULTS

Fresh newborn grafts were revascularized successfully at a rate of 80% (16 of 20). After 24 hours of preservation, 65% (13 of 20), 75% (15 of 20), and 85% (17 of 20) of the grafts were observed to be revascularized in LR, m-TOM, and UW solutions, respectively. After 48 hours of preservation, 60% (12 of 20), 80% (16 of 20), and 80% (16 of 20) of the grafts also were revascularized in the respective solutions (no statistic difference among the groups). The cold-preservation did not affect the neovascularization of newborn intestine until 48 hours. Histologic findings of the preserved intestine and biochemical analyses showed that UW and m-TOM solutions kept villous architectures of the preserved grafts, however, might be harmful to enterochromaffin cells.

CONCLUSION

Long-time preservation of newborn intestine did not interfere with neovascularization and maturation. J Pediatr Surg 36:1805-1810.