Structural analysis of leucine-rich-repeat variants in proteins associated with human diseases

A number of human diseases have been shown to be associated with mutation in the genes encoding leucine-rich-repeat (LRR)-containing proteins. They include 16 different LRR proteins. Mutations of these proteins are associated with 19 human diseases. The mutations occur frequently within the LRR domains as well as their neighboring domains, including cysteine clusters. Here, based on the sequence analysis of the LRR domains and the known structure of LRR proteins, we describe some features of different sequence variants and discuss their adverse effects. The mutations in the cysteine clusters, which preclude the formation of sulfide bridges or lead to a wrong paring of cysteines in extracellular proteins or extracellular domains, occur with high frequency. In contrast, missense mutations at some specific positions in LRRs are very rare or are not observed at all.

Development of Taenia saginata asiatica metacestodes in SCID mice and its infectivity in human and alternative definitive hosts

Development of Taenia saginata asiatica metacestodes in SCID mice, and its infectivity in humans, golden hamsters, and Mongolian gerbils as alternative definitive hosts, were investigated. Cysticerci were recovered from SCID mice that were subcutaneously injected with hatched oncospheres of T. s. asiatica. The morphological changes of metacestodes were observed. The recovered cysticerci were fed to gerbils, hamsters and humans, to check for their infectivity. Tapeworms were recovered from gerbils and hamsters fed with 20 to 45 week-old cysticerci, and proglottids excretions were observed in human volunteers fed with 45 week-old cysticerci. However, no tapeworms were recovered from gerbils fed with 10 week-old cysticerci. Our results suggest that T. s. asiatica oncospheres needed more than 20 weeks to develop to maturity in SCID mice to be infective to both their natural and alternative definitive hosts.

Detection of nonmelanoma skin cancer micrometastases in lymph nodes by using reverse transcriptase-polymerase chain reaction for keratin 19 mRNA

BACKGROUND

A new sensitive method for the detection of skin cancer micrometastases in lymph nodes is based on amplification of keratin 19 (K19) mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR).

OBJECTIVES

To compare results of RT-PCR with those of histological examination in terms of the detection rate of skin cancer micrometastases.

METHODS

Twenty-six lymph nodes obtained from 13 patients with squamous cell carcinoma (SCC), eccrine porocarcinoma and Paget's disease were investigated by histological examination (haematoxylin and eosin sections) and RT-PCR. RT-PCR was performed on extracted RNA by using K19 primer pairs. RT-PCR products were visualized by ethidium bromide staining and confirmed by non-radioactive hybridization with K19-specific probes.

RESULTS

All of 10 histologically positive lymph nodes yielded the expected 460-bp band. Of the 16 histologically negative lymph nodes, one (6%) was found by RT-PCR to express K19 mRNA, indicating the presence of micrometastases which could not be detected by histological examination. A serial dilution study using RNA extracted from SCC cells mixed with RNA extracted from normal lymph node cells showed a detection sensitivity of K19 RT-PCR of 10-5 micro g cancer cell RNA in 1 micro g lymph node RNA. Nested RT-PCR showed a detection sensitivity of one tumour cell in 106 lymphocytes.

CONCLUSIONS

These results demonstrate the usefulness of K19 RT-PCR for the detection of skin cancer micrometastases in lymph nodes.

A case of germinoma in the septum pellucidum manifesting as amnesia and hemiparesis

BACKGROUND

We report a rare case of germinoma mainly located in the septum pellucidum.

CASE DESCRIPTION

A 19-year-old man presented with germinoma located in the septum pellucidum manifesting as amnesia and right hemiparesis. Magnetic resonance imaging demonstrated a heterogeneously enhanced mass in the septum pellucidum and abnormal T2-weighted signals in the left basal ganglia. An anterior transcallosal approach was performed to remove the mass in the septum pellucidum. The histological diagnosis was germinoma. Radiotherapy and chemotherapy were given. He was discharged with slight amnesia and right hemipareis.

INTERPRETATION

Intracranial germinoma can arise from the septum pellucidum.

Retarded gastric acid secretion in rats infected with larval Taenia taeniaeformis

The influence of hepatic larval Taenia taeniaeformis infection on gastric acid secretory activity and gastric mucosal integrity was investigated. After 12 weeks of infection with 2,000 T. taeniaeformis eggs, the gastric pH values of control and infected rats were 4.1+/-0.6 (mean +/- SD) and 8.4+/-0.2, respectively. There was no difference in the basal acid secretion between control (1.7+/-0.7 micro Eq.H(+)/15 min) and infected (1.9+/-0.3) rats. However, infected rats failed to respond to histamine stimulation, the maximum acid output level being 2.8+/-0.4 in the infected rats, compared to 12.9+/-3.3 in control rats. Larval T. taeniaeformis infection resulted in the suppression of gastric acid secretion leading to hypergastrinemia.

Potential remedy against Echinococcus multilocularis in wild red foxes using baits with anthelmintic distributed around fox breeding dens in Hokkaido, Japan

The effect of bait-delivered anthelmintic to reduce the prevalence of Echinococcus multilocularis in wild red foxes was evaluated in Koshimizu, in the eastern part of Hokkaido, Japan. The study area (200 km2) was divided into baited and non-baited sections. The anthelmintic baits were distributed around fox den sites in the baited section every month for 13 months. After 1 year of the anthelmintic bait distribution, the prevalence of E. multilocularis in foxes, evaluated either by the parasite egg examination (from 27.1 to 5.6%) or coproantigen ELISA (from 59.6 to 29.7%), decreased in the baited section contrasting to that in the non-baited section (parasite egg: from 18.8 to 24.2%; ELISA: from 41.9 to 45.8%). The prevalence of E. multilocularis in grey red-backed vole Clethrionomys rufocanus, caught around fox dens, born after bait distribution also decreased and was significantly lower than that in non-baited section. However, within the study periods, the coproantigen-positive rate in fox faeces sporadically increased, while egg-positive rate constantly decreased. Since coproantigen ELISA can detect pre-patent infection, this observation indicates that reinfection pressure in the baited section was still high even after the 13 months of anthelmintic bait distribution. Therefore, the bait distribution longer than our study period is required for the efficient control of E. multilocularis in wild red fox population.

The expression of cell cycle regulatory proteins in oligodendroglial tumors

Oligodendroglial tumors are mainly classified histologically into 2 types of tumors--oligodendrogliomas and oligoastrocytomas--whether the tumor includes astrocytic component or not, and these are, respectively, divided histologically into 2 different malignant groups, low-grade (WHO grade II) and high-grade or anaplastic (WHO grade III). In this study, we investigated the expression of the cell cycle-related proteins and analyzed the relationship between the labeling index (LI: the percentage of positive nuclei) of these proteins and 2 histopathological phenotypes, grade and prognosis. Forty-four specimens were examined, including 11 oligodendorogliomas (0), 5 oligoastrocytomas (OA), 18 anaplastic oligodendrogliomas (aO) and 10 anaplastic oligoastrocytomas (aOA), according to the WHO classification. Of these, 19 specimens were obtained from recurrent tumors of 8 cases. The mean LI of all the investigated proteins between O and OA, and aO and aOA showed no significant differences. The mean MIB-1 LI, pRb LI, p53 LI and p14 LI of GIII were significantly higher than GII, while the mean p27 LI of GIII was significantly lower than GII. In the recurrent cases, we noted correlations between the disease-free period and MIB-1 LI (inverse), p27 LI and p14 (inverse). Significant correlations were noted between MIB-1 LI and pRb LI, MIB-1 LI and cycD1 LI, MIB-1 LI and p27 LI (inverse), pRb LI and cycD1 LI, cycD1 LI and cdk4 LI and pRb LI and p27 LI (inverse) in the pRb/cycD1-cdk4/p27 pathway, and between MIB-1 LI and p53 LI, MIB-1 LI and p14 LI, p53 LI and p14 LI, p53 LI and MDM2 LI and MDM2 LI and p14 LI in the p53/MDM2/p14 pathway. In conclusion, both pRb/cycD1-cdk4/p27 and p53/N4DM2/p14 pathways correlate with malignant progression, and MIB-1 LI, pRb LI, p27 LI, p53 LI and p14 LI reflect the histopathological malignancy of oligodendroglial tumors. MIB-1 LI, pRb LI and p27 LI are especially useful as indicators of malignancy of oligodendroglial tumors.

Novel development of exciton-coupled circular dichroism based on induced axial chirality

[reaction--see text] A simple method for determining the absolute configuration of chiral alcohols with a unique chromophoric reagent 1 based on induced exciton chirality has been developed. Practical usefulness of the present method was demonstrated by the determination of the absolute configuration of 17,18-dihydroxybergamottin.

Congestion of superior mesenteric veins and small bowel mucosal injury after endoscopic treatment of esophageal varices in patients with portal hypertension

We investigated treatment-induced changes in venous return from the small bowel and small bowel intestinal mucosal injury induced by the treatment of esophageal varices in patients with portal hypertension. A total of 14 patients (age 59.8+/-9.5 years, five women and 9 men) who received prophylactic treatment of esophageal varices between December 1998 and March 1999 were investigated. Diamine oxidase (DAO) activity was measured before and after treatment. Changes in blood flow of the portal and superior mesenteric veins were investigated by Doppler ultrasonography in six patients. A significant decrease in DAO activity was observed three days after treatment (11.5+/-1.6 units/liter prior to treatment versus 8.6+/-1.6 units/liter three days after treatment; P < 0.001). Decreases in superior mesenteric and portal venous flow velocity were observed in four and three patients, respectively. In two patients with an increase in the cross-sectional area of the superior mesenteric vein with delayed venous return, a marked decrease in DAO activity was observed three days after treatment. In patients with portal hypertension, rapid reduction of pooling of portal flow caused by the treatment of esophageal varices can induce transient congestion of the mesenteric venous system which can produce some small bowel mucosal injury.

Effects of selected metal ions on photodegradation of organophosphorus pesticides sensitized by humic acids

Selected metal ions having paramagnetic property were found to exert inhibition effects on aquatic photodegradation of organophosphorus pesticides sensitized by humic acids, according to the increasing order of Cr(III) < Co(II) < Mn(II) < Cu(II). Basic factors dominating the metal-ion effects were clarified on the basis of the fluorescence quenching as well as radical scavenging abilities of metal ions complexed with humic acids.

Meshy meningioma: a potential novel variant

A potential novel variant of meningioma is reported. The tumor was solid, hard, white-colored, well circumscribed in a fibrous capsule and fixed to the dura, showing no invasion into the brain parenchyma. Histopathological study presented a sparsely cellular tumor composed of cells with fine reticular or mesh-like cytoplasm, each containing an oval nucleus. Mitotic figures were rarely seen. Immunohistochemical studies of tumor cells showed positive immunoreactivity for vimentin and epithelial membrane antigen but were negative for GFAP, desmin, neurofilament, keratin, S-100, CD34 and CEA. Bipolar neoplastic cells and long processes were noted on ultrastructural observation; these were attached side by side to each other by desmosomes, resulting in a mesh-like configuration. Perinuclear cytoplasm and processes were rich in intermediate filaments and rough endoplasmic reticulum. These microscopic and ultrastructural features have never before been reported among the variants of meningioma. The name 'meshy meningioma' is proposed for this novel variant.

Participation in psychosocial group intervention among Japanese women with primary breast cancer and its associated factors

Though psychosocial group intervention is considered in the West to be an important source of support for reducing psychosocial distress in cancer patients, in Asian countries, there has been no research as yet on the needs for such intervention. This study investigated the level of participation and interest in psychosocial group intervention plus any associated factors in 151 primary breast cancer patients. All were less than 65 years old at 4-18 months post-surgery. Of the 126 subjects who responded (response rate 83%), 53 (42%) participated (participants) and 73 (58%) did not (non-participants). Participation was greater among those with a high level of anxiety measured by the Hospital Anxiety and Depression Scale (HADS) (odds ratio [OR], 3.25; 95% confidence interval [CI], 1.07-10.42), those who had undergone surgery within the last 12 months (OR, 3.10; 95% CI, 1.35-7.55), and those who were 50-65 years old (OR, 3.08; 95% CI, 1.33-7.66). Among the non-participants, 53 (73%) were interested in the intervention while 20 (27%) were not. Non-participants without any interest in the psychosocial group intervention had significantly higher anxiety levels than those with interest (t=-2.08; df=71; p=0.03). These results suggest that most Japanese breast cancer patients who need psychological support can be sought out by asking whether they are willing to participate in a psychosocial group intervention. However, the minority not interested in any psychological group intervention might need other supports such as medication or individual psychotherapy.

A survey of canine echinococcosis in Gobi Altai Province of Mongolia by coproantigen detection

Few studies have been carried out for the prevalence of canine echinococcosis in Mongolia. This study was designed to elucidate a preliminary information of the prevalence from feces collected in the field. Sixty-seven fecal samples from dogs and 2 red foxes in Altai town were collected and examined for Echinococcus coproantigen and eggs. Coproantigen detection was performed by a sandwich ELISA using a monoclonal antibody EmA9 raised against Echinococcus multilocularis somatic antigen. Of the dog samples examined, 17 (25.4%) were positive by the ELISA. One out of two foxes was positive, too. Taeniid egg-positive feces were recognized in 12 dog feces. Only 6 samples were both coproantigen and egg positive. Eggs of Ancylostoma sp., Trichuris sp.; and Capillaria sp.; were also registered.

Inhibitory effect of different UV lamps on the infectivity of taeniid eggs

The expanding distribution of alveolar echinococcosis in Hokkaido, Japan necessitates a search for control measures, particularly for killing Echinococcus eggs; and UV radiation is a potential tool. To determine the effective UV lamp and its optimum duration of exposure to inhibit the infectivity of taeniid eggs, three UV lamps (UVA, UVB and UVC) with peak emissions at different wavelengths were used to irradiate eggs of Taenia taeniaeformis. Irradiation was done in durations of 30, 90, 270, 810, 2,430 and 7,290 s. Infectivity of the irradiated eggs was tested by oral inoculation into rats. The inhibitory effect of the UV lamps at different exposure durations was determined by the reduction in the larval cyst establishment and by the delay of larval development. The UVC lamp (narrow peak at 254 nm) was found to be the most effective lamp at an exposure duration of more than 2,430 s (2,430 mJ/cm2), attaining 100% reduction. Also, shorter exposure durations produced a significant effect on the development of irradiated eggs in a greater percentage of small cysts (> 1 mm) among the metacestodes. Irradiation delayed the development of some cysts, as observed in histopathological sections. UVA and UVB lamps were not able to attain 100% reduction. It is concluded that the UVC lamp can be used as a tool in sterilizing taeniid eggs and is thus a promising method to control echinococcosis, although it may require a higher intensity of exposure.

Ataxia telangiectasia with vascular abnormalities in the brain parenchyma: report of an autopsy case and literature review

A 25-year-old man was admitted to the Department of Neurology, Gunma University Hospital, in June 1997. He had an intellectual disability and had suffered from repeated infection since childhood. Cerebellar ataxia had developed at 19 years of age and he had been clinically diagnosed with ataxia telangiectasia (AT) comprising cerebellar ataxia and oculocutaneous telangiectasia at 24 years of age. He died from pneumonia and renal failure at 26 years of age. Neuropathological examination revealed Purkinje cell loss and atrophy of the dentate nuclei in the cerebellum, anterior horn-cell atrophy and demyelination of the gracile fasciculi in the spinal cord, and the existence of nucleocytomegalic cells in the anterior pituitary gland. These neuropathological findings correlated with previously reported cases of AT. In addition, spongy degeneration was found, predominantly around the blood vessels in the cerebral cortex. Diffuse spongy degeneration and multiple foci of coagulative necrosis with calcification were noted in the white matter. Abnormal vasculature was noted in both degenerative and necrotic areas in the cerebral cortex and in the white matter. The vessels at the center of the areas of spongy degeneration in the cerebral cortex had irregularly arranged and enlarged smooth-muscle-cell nuclei and a distorted, narrow lumen. The vessels present in the white matter were hyalinized. To our knowledge, these vascular abnormalities in the brain parenchyma have not been reported previously.

First report of Trichinella nativa in red foxes (Vulpes vulpes schrencki) from Otaru City, Hokkaido, Japan

Forty-three red foxes (Vulpes vulpes schrencki) and nine raccoon dogs (Nyctereutes procyonoides viverrinus) were captured in Otaru City, Hokkaido, Japan and examined by muscle digestion for the presence of Trichinella sp. larvae. Of the foxes, five (11.6%) were positive for larvae of Trichinella nativa while none of the raccoon dogs were found to be positive. This finding suggests that the red foxes are important reservoir hosts of sylvatic trichinellosis in Otaru, Hokkaido. This is the first report on Trichinella nativa in wild red foxes of Hokkaido, Japan.

Neurofibromatosis type 1-associated unusual pleomorphic astrocytoma displaying continual malignant progression

Patients with neurofibromatosis type 1 (NF1) often have gliomas as a complication, most of which are benign pilocytic astrocytomas which have arisen in optic pathways. In the present case, a 17-year-old girl (at death) with stigmata of NF1, initially had a bulky tumor mass in the left thalamus, developing into the lateral ventricle, at 13 years of age. Partially resected tissue samples showed pleomorphic astrocytoma with abundant xanthoma cells and degenerative structures such as Rosenthal fibers (RF) and eosinophilic granular bodies. Fine eosinophilic granules identical to RF, both immunophenotypically and ultrastructurally, were also seen. The residual tumor was subtotally resected 6 months later, and the tumor histology was essentially similar as before, accompanying the regenerative structures; this was believed to be a good prognostic indicator. However, several anaplastic features such as mitosis, necrosis and vascular proliferation appeared even in areas rich in the regenerative structures. After a 2-year, disease-free interval, multiple tumor relapse occurred in June 1997. Partially resected tumor tissues were composed of monotonous small anaplastic cells with prominent proliferative activity. Surprisingly, the tumor cells had retained eosinophilic granules within the cell bodies. Postoperative chemotherapy with procarbazine, MCNU and vincristine (PCV) suppressed the residual tumor dramatically, but the regrowing tumor finally became uncontrollable, leading to the patient's death. TP53 mutation was not detected, while p27 immunopositivity was constantly high during malignant progression, suggesting acquisition of proliferative activity to overcome p53 and p27 inhibitory functions. A review of previously published reports failed to reveal any cases of this type.

Association between a polymorphism of the transforming growth factor-beta1 gene and genetic susceptibility to ossification of the posterior longitudinal ligament in Japanese patients

STUDY DESIGN

A study was conducted to determine the association between polymorphism of the transforming growth factor-beta1 (TGF-beta1) gene and ossification of the posterior longitudinal ligament (OPLL) prevalence.

OBJECTIVE

To examine whether the T869-->C polymorphism of the TGF-beta1 gene is associated with genetic susceptibility to OPLL in Japanese subjects.

SUMMARY OF BACKGROUND DATA

In the posterior longitudinal ligament, OPLL is associated with abnormal calcium metabolism. Several candidate genes are associated with the prevalence of OPLL. In the ossified matrix and chondrocytes of adjacent cartilaginous areas of OPLL, TGF-beta1 is overexpressed.

METHODS

The TGF-beta1 genotype was identified with an allele-specific polymerase chain reaction method in 319 Japanese subjects (46 subjects with OPLL and 273 control subjects).

RESULTS

There was a significant association between the T869-->C genotype and the prevalence of OPLL in the cervical spine. Multivariable logistic regression analysis, adjusted for gender, age, height, and body weight, showed that the frequency of the C allele was significantly higher in subjects with OPLL than in control subjects.

CONCLUSIONS

The T869-->C polymorphism of the TGF-beta1 gene is a genetic determinant of a predisposition to OPLL, with the C allele representing a risk factor for genetic susceptibility to OPLL in Japanese subjects. Therefore, TGF-beta1 genotyping may be useful in the prevention of OPLL.