Radiographic classification of Os odontoideum and its clinical significance

STUDY DESIGN: This study analyzed the relationship between the configuration of the atlantoaxial joint and the clinical characteristics of patients with os odontoideum. OBJECTIVES: To compare three types of atlantoaxial configurations of os odontoideum from the viewpoint of clinical characteristics. METHODS: Twelve patients were classified into the following three types according to their atlantoaxial configuration on an anteroposterior radiogram: round (n = 6), cone (n = 4), and blunt-tooth (n = 2). Clinical features in each group were compared in terms of mean age, gender distribution, severity and type of myelopathy, and degenerative findings of the atlantoaxial joint. RESULTS: The patients in the round type group were predominantly women and had more severe myelopathy than that of patients in the other groups. According to Crandall's classification of myelopathy, all patients showed the transverse lesion syndrome in the cone and blunt-tooth types. Four of six patients with the round type of atlantoaxial configuration had the Brown-Séquard syndrome. With the round type, it appeared that the lateral mass of the axis tended to dislocate laterally, and this lateral instability associated with anteroposterior instability was believed to induced the Brown-Séquard syndrome. CONCLUSIONS: Myelopathy in patients in the round type group was the most severe compared with that of patients in the other three groups. This classification is considered useful for estimating clinical findings in os odontoideum.     

Acetabular osteolysis and migration in bipolar arthroplasty of the hip: five- to 13-year follow-up study

Two factors potentially determining the consistent overexpression of sialyl-Le(x) antigen in colon carcinoma and metastases were investigated: (i) the expression of the mucins MUC1 and MUC2, known to carry sialyl-Le(x), by Northern blotting; (ii) the extent of sialic acid O-acetylation, by Western blotting and HPLC. RNA and sialyl-Le(x)-positive mucins were purified from normal colonic mucosa (N), primary carcinomas (T) and their liver metastases (M). Northern blots showed that mRNA expression both of MUC1 and of MUC2 decreases during the progression of the disease, and is lowest in metastatic tissue. The expression of mucin-bound sialyl-Le(x) increased strongly from N to T and, to a lesser extent, to M. After alkali treatment of the mucins these differences disappeared, indicating that the total amount of mucin-bound sialyl-Le(x) is the same in the 3 types of tissues. The O-acetylation of mucin-bound sialyl-Le(x) gradually decreased from N to M. HPLC analysis showed that in N about 70%, in T 45% and in M only 20% of mucin-bound sialic acids are O-acetylated. Thus, the increase of sialyl-Le(x) detectable during colon-carcinoma progression is due to diminished O-acetylation and not to increased expression of mucin protein cores. The decrease of O-acetylation is therefore the primary chemical alteration contributing to colon carcinoma-associated overexpression of sialyl-Le(x).     

Acquired dural arteriovenous malformations of the lumbar spine: case report

OBJECTIVE AND IMPORTANCE: Although dural arteriovenous malformations (AVMs) are considered to be acquired, no conclusive evidence has been obtained. The first case of dural AVMs of the lumbar spine that showed evidence supporting their being acquired lesions is described. CLINICAL PRESENTATION: A 27-year-old man was admitted to our hospital in November 1994, presenting with increasing pain and numbness in the left buttock to the left lower limb. Myelography and arteriography showed dural AVMs of the lumbar spine. However, the myelogram obtained before surgery for lumbar disc herniation in 1987 provided no findings suggestive of intradural vascular anomalies. INTERVENTION: Embolization procedures via the left iliolumbar arteries were performed. However, there was no improvement of the symptoms, and the patient underwent surgical treatment. CONCLUSION: The present report documents a case of dural AVMs of the lumbar spine that showed evidence supporting their being acquired lesions.     

Clinicopathologic features of neuroendocrine carcinomas of the stomach: appraisal of small cell and large cell variants

OBJECTIVE: To clarify the clinicopathologic features of neuroendocrine carcinomas (NECs) of the stomach, we reviewed 56 cases of surgically treated gastric carcinomas with a solid growth or with areas containing patterns characteristic for neuroendocrine (NE) tumors. METHODS: Of the 56 cases reviewed, we selected 33 cases of NEC based both on histologic patterns common to NE tumors and on histochemical/immunohistochemical results. RESULTS: The average age of patients with NEC was 69.8 years (range, 44-92 years). The majority of patients were men (male-female ratio, 23:10). The most frequently affected site was the upper third (46%) of the stomach. Grossly, 9 cases of NEC were fungating and 24 were ulcerated. As compared with 23 patients with non-NEC tumors, the patients with NECs had a worse prognosis. Histologically, NECs had a variety of histologic patterns, including solid, organoid, trabecular, pseudoglandular, spindle cell, and rosettelike. Based on both cell size and morphologic features, we subdivided NECs into 2 variants, namely, small cell NEC and large cell NEC. Our series included 12 cases of small cell NEC and 21 cases of large cell NEC. CONCLUSIONS: Compared with small cell NECs, large cell NECs had a higher mitotic count, larger polygonal cells, a lower nuclear-cytoplasmic ratio, coarser nuclear chromatin, and more frequent conspicuous nucleoli. Large cell NEC was an aggressive tumor with a very poor prognosis (median survival time, 15.2 months; 1-year survival rate, 58%), which approached that for small cell NEC.     

Ultrahigh-speed pseudomorphic InGaAs/InAlAs HEMTs with 400-GHzcutoff frequency

An excellent cutoff frequency (f_t) as high as 400 GHz was successfully realized in 45-nm-gate pseudomorphic InGaAs/InAlAs high electron mobility transistors (HEMTs). An additional vertical gate-recess suppressed short-channel effects, while keeping good pinchoff characteristics. Gate length (L_g) dependence of electron transit time (τ_transit) implied an increased saturation velocity (υ_s) of 3.6×10⁷ cm/s in the developed pseudomorphic HEMTs. This f_t is the highest value ever reported for any transistors to date     

Disseminated carcinomatosis of the bone marrow occurring 11 years after subtotal gastrectomy for gastric cancer]

A 44-year-old man was admitted to our hospital because of purpura, increased serum alkaline phosphatase, and thrombocytopenia. He had undergone subtotal gastrectomy for gastric cancer 11 years earlier. A biopsy specimen of the bone marrow revealed metastatic mucin-forming, moderately differentiated adenocarcinoma. Because the primary tumor was not detected in any other organ, the gastric cancer the patient was treated for 11 years earlier was suspected as the primary tumor. Microangiopathic hemolytic anemia and disseminated intravascular coagulation developed during the clinical course, and the patient deteriorated despite treatment with anticoagulants. Finally, he died of pulmonary carcinomatous lymphangitis. Autopsy revealed a small number of adenocarcinomatous cells in the lymphoduct of the remaining stomach in spite of its mucosa being intact. We concluded that the bone marrow was infiltrated by cancer cells which originated in the stomach 11 years before. It is unclear why adenocarcinoma cells remained dormant for as long as 11 years in the gastric lymphoduct and bone marrow.     

An unusual DNA adduct derived from the powerfully mutagenic environmental contaminant 3-nitrobenzanthrone

The covalent binding of an N-hydroxy metabolite of the powerfully mutagenic 3-nitrobenzanthrone (NBA) to 2'-deoxyguanosine (dG) and calf thymus DNA has been investigated in vitro. The major adduct obtained from the reaction of the N-acetoxy-N-acetyl derivative (N-Aco-N-Ac-ABA) of 3-aminobenzanthrone (ABA) and dG was identified as N-acetyl-3-amino-2-(2'-deoxyguanosin-8-yl)benzanthrone (dG-N-Ac-ABA) by 1H NMR and mass spectroscopies as well as by the reaction of N-Aco-N-Ac-ABA with the double-stranded calf thymus DNA. The coupling with the dG moiety occurred exclusively at C-2 of benzanthrone (BA), suggesting a significant contribution of a resonance-stabilized arenium ion intermediate derived from BA to the production of this new type of adduct. The preferred conformation of the adduct has been shown to be syn by 1H and 13C NMR.     

The effects of dissolved organic matter on the decomposition of di-n-butyl phthalate by ozone/hydrogen peroxide process.

The effects of the dissolved organic matter (DOM) on the ozone decay and the di-n-butyl phthalate (DBP) decomposition during ozone/hydrogen peroxide (O3/H2O2) process were investigated (DBP-d4 was used instead of DBP). Four surface waters, two secondary municipal sewage effluents (SMSEfs) and Suwannee river natural organic matter were used as DOM. The ozone decompositions in the DOM solutions were separated by instantaneous ozone consumption and slower ozone decay. The effect of H2O2 addition on the ozone decay was clearly observed at slower ozone decay. Ozone decomposition rate at slower ozone decay increased linearly with H2O2 dose. DBP-d4 was exponentially decreased with ozone consumption. Ozone consumption required to decompose 90% of DBP-d4 ((deltaO3)90%) in SMSEFs was higher than those in surface waters. The (deltaO3)90% per DOC of DOM values were from 22 to 23 micromole/mgC for SMSEFs and from 10 to 17 micromole/mgC for surface waters. The (deltaO3)90% values were correlated to specific ultraviolet absorbance at 254 nm (SUVA254) for surface waters.     

Transistor operation of 30-nm gate-length EJ-MOSFETs

We have fabricated electrically variable shallow junction metal-oxide-silicon field-effect transistors (EJ-MOSFET's) to investigate transistor characteristics of ultrafine-gate MOSFET's. By using EB direct writing onto an ultrahigh-resolution negative resist (calixarene), we achieved a gate length of 32 nm for the first time. The short-channel effects were effectively suppressed by electrically induced ultrashallow source/drain regions, and the fabricated device exhibited normal transistor characteristics even in the 32-nm gate-length regime at room temperature: an ON/OFF current ratio of 10 ⁵ and a cut-off current of 20 pA/μm