Diffuse pachymeningeal hyperintensity and subdural effusion/hematoma detected by fluid-attenuated inversion recovery MR imaging in patients with spontaneous intracranial hypotension.

BACKGROUND AND PURPOSE: Fluid-attenuated inversion recovery (FLAIR) MR imaging has advantages to detect meningeal lesions. FLAIR MR imaging was used to detect pachymeningeal thickening and thin bilateral subdural effusion/hematomas in patients with spontaneous intracranial hypotension (SIH). MATERIALS AND METHODS: Eight patients were treated under clinical diagnoses of SIH. Chronologic MR imaging studies, including the FLAIR sequence, were retrospectively reviewed. RESULTS: Initial MR imaging showed diffuse pachymeningeal thickening as isointense in 6 cases, hypoisointense in 1 case, and isohyperintense in 1 case on the T1-weighted MR images, and hyperintense in all cases on both T2-weighted and FLAIR MR images. Dural (pachymeningeal) hyperintensity on FLAIR MR imaging had the highest contrast to CSF, and was observed as linear in all patients, usually located in the supratentorial convexity and also parallel to the falx, the dura of the posterior fossa convexity, and the tentorium, and improved after treatment. These characteristics of diffuse pachymeningeal hyperintensity on FLAIR MR imaging were similar to diffuse pachymeningeal enhancement (DPME) on T1-weighted imaging with gadolinium. Initial FLAIR imaging clearly showed subdural effusion/hematomas in 6 of 8 patients. The thickness of subdural effusion/hematomas sometimes increased transiently after successful treatment and resolution of clinical symptoms. CONCLUSION: Diffuse pachymeningeal hyperintensity on FLAIR MR imaging is a similar sign to DPME for the diagnosis of SIH but does not require injection of contrast medium. FLAIR is useful sequence for the detection of subdural effusion/hematomas in patients with SIH.

Assessment of hemorrhage in pituitary macroadenoma by T2*-weighted gradient-echo MR imaging.

BACKGROUND AND PURPOSE: Intratumoral hemorrhage occurs frequently in pituitary macroadenoma and manifests as pituitary apoplexy and recent or old silent hemorrhage. T2*-weighted gradient-echo (GE) MR imaging is the most sensitive sequence for the detection of acute and old intracranial hemorrhage. T2*-weighted GE MR imaging was used to investigate intratumoral hemorrhage in pituitary macroadenomas. MATERIALS AND METHODS: Twenty-five consecutive patients who underwent total or subtotal resection of pituitary macroadenoma with heights from 17 to 53 mm, including 1 patient with classic pituitary apoplexy, underwent MR imaging before surgery, including T2*-weighted GE MR imaging. For histologic assessment of the hemorrhage in whole surgical specimens, we used hematoxylin-eosin staining. RESULTS: T2*-weighted GE MR imaging detected various types of dark lesions, such as "rim," "mass," "spot," and "diffuse" and combinations, indicating clinical and subclinical intratumoral hemorrhage in 12 of the 25 patients. The presence of intratumoral dark lesions on T2*-weighted GE MR imaging correlated significantly with the hemorrhagic findings on T1- and T2-weighted MR imaging (P < .02 and <.01, respectively), and the surgical and histologic hemorrhagic findings (P < .001 and <.001, respectively). CONCLUSION: T2*-weighted GE MR imaging could detect intratumoral hemorrhage in pituitary adenomas as various dark appearances. Therefore, this technique might be useful for the assessment of recent and old intratumoral hemorrhagic events in patients with pituitary macroadenomas.

Dysplastic ganglioneurocytoma with increased glucose metabolism: a heterotopia with unique histopathology.

A 1 year and 7 month old boy was incidentally found to have an intracranial mass lesion at the frontal base. The mass was 45 x 54 x 47 mm in size, contained a calcification, a few small cysts, and extended downward to the sphenoid sinus and upper pharynx. The signal intensity of the lesion on magnetic resonance imaging was iso-high on T1-weighted images, and slightly high on T2-weighted images, and it did not enhance with gadolinium injection. Although there was no obvious mass effect, 18F-fluorode-oxyglucose positron-emission tomography demonstrated increased uptake, and a surgical resection was performed suspecting a neoplastic lesion. Histologically, the lesion consisted of small to large anomalous neurons and glial cells but lacked normal cortical architecture. Cellularity was high in some portion with MIB-1 labeling index of 2%, but there was no cellular atypia suggestive of neoplasm. Therefore, this lesion was considered to be a dysplasia that does not fit into the previously described entity. We suggest this lesion would be better described as dysplastic ganglioneurocytoma.

Wave-like appearance of diffuse pachymeningeal enhancement associated with intracranial hypotension.

Diffuse pachymeningeal enhancement on magnetic resonance (MR) imaging is important in identifying spontaneous and secondary intracranial hypotension (IH) [cerebrospinal fluid (CSF) hypovolemia] in patients with postural headache, because CSF pressure at lumbar puncture is variable. We examined the pachymeningeal enhancement pattern in patients with IH. MR imaging findings of pachymeningeal enhancement were examined before and after treatment in seven consecutive patients with spontaneous IH and one patient with IH after lumbar puncture. Diffuse non-nodular dural enhancement was observed in all patients. Characteristic thick, uninterrupted, enhancement was observed, mainly in the dura of the frontal, temporal, and retroclival regions, and the tentorium. Thin and uninterrupted, or partially interrupted, enhancement was observed, mainly in the parieto-occipital region and cerebellar convexity. Curved linear enhancement was observed along the calvarium of all patients. A wave-like appearance, a clear pattern of dural unevenness parallel to the brain, was detected in the frontal and temporal regions, near the base, in all patients. A wave-like appearance, especially in the frontal and temporal base, may be a characteristic MR imaging indicator of IH.

Incidentally detected parafalcine chondrosarcoma.

Parafalcine chondrosarcoma is extremely rare, and may be difficult to differentiate preoperatively from falx meningioma. An 18-year-old woman presented with a parafalcine chondrosarcoma incidentally detected as a small lesion 2 years before admission, suggesting falx meningioma. Brain computed tomography and magnetic resonance imaging just before admission revealed the parafalcine lesion had increased by about nine times in volume during the last 2 years. Single-photon emission computed tomography (SPECT) after intravenous administration of both thallium-201 chloride ((201)TlCl) and N-isopropyl-p-[(123)I]iodoamphetamine ((123)I-IMP) demonstrated no abnormal uptake of either tracer. Histological examination revealed classic low-grade chondrosarcoma. Parafalcine chondrosarcoma should be considered at this site if relatively rapid growth is observed. SPECT using (201)TlCl and (123)I-IMP may be useful to discriminate parafalcine low-grade chondrosarcoma from meningioma or other tumours originating in this region.

High incidence and spontaneous resolution of mastoid effusion after craniotomy on early postoperative magnetic resonance images.

Mastoid effusion is a poorly understood complication after craniotomy. The incidence and severity of postoperative mastoid effusion were retrospectively examined on postoperative magnetic resonance (MR) images to assess any association with craniotomy procedures, time course, and neuro-otological complications. We evaluated the early postoperative MR images (within 4 days of craniotomy) and medical records of 74 patients who underwent 77 operations for the treatment of various intracranial diseases from January 2000 to December 2001. Mastoid effusion was classified into four grades: none, partial, moderate, and severe diffuse effusion in the mastoid air cells. Thirty-three follow-up MR images from 26 patients were also reviewed. Postoperative mastoid effusion occurred ipsilateral to the craniotomy site in 62 cases and contralateral in 56 cases. Mastoid effusion was significantly more severe ipsilateral than contralateral to craniotomy with exposure of the mastoid air cells ( P<0.0001). There was no significant difference in severity between the contralateral and ipsilateral sides after craniotomy without mastoid air cell opening ( P=0.437). Mastoid effusion following craniotomy without exposure of mastoid air cells resolved within 3 months. However, otitis media with effusion developed in six patients with severe mastoid effusion ipsilateral to craniotomy with exposure of the mastoid air cells. Mastoid effusion frequently developed on both sides. Any grade of mastoid effusion on the ipsilateral side to craniotomy without exposure of mastoid air cells, or on the contralateral side, was asymptomatic or had a benign course, and disappeared within 3 months.

Spinal epidural metastasis from pineal germinoma.

A 16-year-old boy first presented with a pineal tumour identified by neuroimaging but without positive serum or cerebrospinal fluid markers. The tumour disappeared after 50 Gy cranial irradiation. One year later he returned with spinal epidural metastasis from the pineal germinoma and required emergency surgery. Intraoperative findings showed that the spinal tumour had originated from cerebrospinal fluid dissemination and had passed through the spinal nerve sleeve. The pathologic diagnosis of the tumour was of a pure germinoma metastasis. An epidural tumour frequently requires emergency diagnosis and treatment. Attention should be paid to the possibility of this rare but serious clinical situation caused by a metastasis from a pineal germinoma.

Contractile responses to reactive oxygen species in the canine basilar artery in vitro: selective inhibitory effect of MCI-186, a new hydroxyl radical scavenger.

BACKGROUND: Cerebral vasospasm is one of the important pathological phenomena which influence morbidity and mortality following subarachnoid haemorrhage. Reactive oxygen species (ROSs) generated by the autoxidation of oxyhemoglobin to methemoglobin may be one of the essential factors in the pathogenesis of cerebral vasospasm. The direct vasocontractile effects of hydrogen peroxide (H(2)O(2)), superoxide anion (O(2)(-)), and hydroxyl radical (*OH) on the canine basilar artery and the inhibitory effects of MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-one), a new *OH scavenger, were investigated. METHOD: Isometric tension was recorded in basilar artery rings from dogs in vitro. H(2)O(2), pyrogallol (O(2)(-) donor), and vitamin C (VitC)/Fe(2+) (*OH-generating system) were used to generate the ROSs. FINDINGS: H(2)O(2) (10 micromol/L), pyrogallol (10 micromol/L), and VitC/Fe(2+) (100 micromol/L each) induced fast onset and transient, slow onset and transient, and sustained contraction, respectively, in the canine basilar artery. Contractions induced by H(2)O(2) were almost completely inhibited by pre-incubation with catalase (800 U/mL) and those by pyrogallol with superoxide dismutase (150 U/mL), but neither with MCI-186 (10 micromol/L). The contraction induced by VitC/Fe(2+) was clearly inhibited by pre-incubation with MCI-186, but not with catalase or superoxide dismutase. INTERPRETATION: ROSs have direct vasocontractile effects on the canine basilar artery in vitro, but different ROSs have different contractile characteristics. Such contractions might be related to the pathophysiology of cerebral vasospasm. MCI-186 had a clear and selective inhibitory effect against *OH-induced contraction in vitro. Comparison of different radical scavengers may be important in pharmacological assessment, especially targeted on cerebral vasospasm.

Calcified vestibular schwannoma with unusual histological characteristics - positive immunoreactivity for CD-34 antigen.

Calcification in vestibular schwannoma is extremely rare. A 36-year-old man presented with a history of decreased hearing on the left since childhood. Computed tomography showed a left cerebellopontine angle lesion protruding into the porus acousticus and enlarging the internal auditory meatus, with significant deposits of calcification. Histological and immunohistochemical examination, including staining for CD-34, a myeloid progenitor cell antigen, found highly degenerated schwannoma with collagen-rich tissue, calcification, formation of bone, abnormal vessels of various sizes, and old haemorrhage with marked haemosiderin-laden macrophages. Most of the surgical specimen was sclerotic collagenous tissue containing sparse spindle-shaped cells which formed approximately 90% of the total specimen. However, the spindle-shaped cells were partly concentrated into islands forming the cellular part (approximately 10% of the total). The spindle-shaped cells in both parts showed almost typical immunohistochemical characteristics of schwannoma. However, many spindle-shaped cells in only the sclerotic part were positive for CD-34, which is widely used for the diagnosis of solitary fibrous tumours. Cerebellopontine angle tumour showing fibromatous tissue, including calcification, may contain foci of typical schwannoma. Careful histological examination with detailed immunohistochemical staining is required for the correct diagnosis. In particular, spindle-shaped cells occasionally show positive immunoreactivity for CD-34 antigen in the areas of degenerated and calcified schwannoma characteristic of our case.

Sphingosine 1-phosphate contracts canine basilar arteries in vitro and in vivo: possible role in pathogenesis of cerebral vasospasm.

BACKGROUND AND PURPOSE: Sphingosine 1-phosphate (S1P) is a platelet-derived bioactive lipid that exerts a variety of biological responses, including vasocontraction. To understand the involvement of S1P in cerebral vasospasm, we investigated the effect of S1P on vasocontraction of the canine basilar artery in vitro and in vivo. METHODS: We recorded isometric tension in basilar arterial rings from dogs in vitro and estimated time-course changes in the diameter of canine basilar arteries and the S1P concentration in cerebrospinal fluid (CSF) by angiography and radioreceptor assays, respectively, after administering S1P into the cisterna magna. Changes in the supernatant S1P concentration during clot formation were monitored by using the in vitro subarachnoid hemorrhage model, in which blood is mixed with CSF. RESULTS: At concentrations ranging between 100 nmol/L and 10 micromol/L, S1P induced a dose-dependent contraction of the basilar artery in vitro. This effect was significantly inhibited by Y-27632, a highly selective Rho-kinase inhibitor. The administration of S1P into the CSF induced a 60% to 70% decrease in the arterial diameter within 15 minutes, and vasocontraction continued for 2 days thereafter. The concentration of S1P in the supernatant during clot formation in vitro reached approximately 300 nmol/L. CONCLUSIONS: S1P induces vasocontraction in the canine basilar artery in vitro and in vivo, possibly through a mechanism involving activation of the Rho/Rho-kinase pathway. Thus, S1P might be considered as a novel spasmogenic substance involved in cerebral vasospasm after subarachnoid hemorrhage.

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (1999)].

From October 1999 to September 2000, we collected the specimen from 430 patients with lower respiratory tract infections in 17 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and antibiotics and patients' characteristics. Of 515 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 506 strains were investigated. The breakdown of the isolated bacteria were: Staphylococcus aureus 78, Streptococcus pneumoniae 101, Haemophilus influenzae 104, Pseudomonas aeruginosa (non-mucoid) 58, P. aeruginosa (mucoid) 11, Moraxella subgenus Branhamella catarrhalis 41, Klebsiella pneumoniae 18, etc. Of 78 S. aureus strains, those with 4 micrograms/ml or above of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) occupied 57.7%. Vancomycin and arbekacin showed the most potent activities against MRSA without detection of ABK-resistant strain (MIC: 64 micrograms/ml) and decrease of VCM-sensitive strains those were found in 1998. The frequency of S. pneumoniae exhibiting low sensitivity to penicillin (penicillin-intermediate S. pneumoniae: PISP + penicillin-resistant S. pneumoniae: PRSP) decreased to 34.7% from 46.0% in 1998. The frequency of PRSP was 3.0%, being the least number after 1991. Carbapenems showed strong activities against S. pneumoniae. Especially, panipenem inhibited the growth of all 101 strains with MIC of 0.063 microgram/ml. Generally, all drugs showed strong activities against H. influenzae with MIC80s of 4 micrograms/ml or below. MICs of ofloxacin ranged between 0.063 microgram/ml and 4 micrograms/ml in 1998, however, those were 0.125 microgram/ml or below in all H. influenzae in 1999 showing the strongest activity. Tobramycin and ciprofloxacin showed strong activities against P. aeruginosa (both mucoid and non-mucoid) with MIC80s of 1 microgram/ml. Number of isolated P. aeruginosa (mucoid) was little as 11, however, the susceptibilities to all drugs were better than P. aeruginosa (non-mucoid). K. pneumoniae showed good susceptibilities to all drugs except for ampicillin with decreasing of low-sensitive strains compared to those detected in 1998. Also, all drugs generally showed strong activities against M. (B.) catarrhalis. MIC80s of all drugs were 2 micrograms/ml or below. The drug which showed the strongest activity was imipenem inhibiting all 41 strains with MIC of 0.063 microgram/ml. On the patients' characteristics, the number of patients aged 80 years or older who had been increased was decreased in 1999 in the distribution by age. The percentage of the elderly patients aged 70 years or older was 47.0%, which occupied almost a half number of the total patients as in the last year. As for the incidence by disease, bacterial pneumonia and chronic bronchitis were the highest. They were noted in 37.9% and 30.5% of the patients, respectively. In 1999, bronchial asthma was frequently observed as compared in recent years. It was noted in about 10% of the patients which is the same % as in bronchiectasis. We examined the number of strains from these patients with infections before and after administration of antibiotics. In patients with bacterial pneumonia, the number of isolated strains was almost the same between those before and after administration. However, in patients with chronic bronchitis, the number of strains remarkably decreased to less than the half of the total after administration of antibiotics in the last year, but it decreased to 2/3 of the total in 1999. On the administration of antibiotics and isolated bacteria by the day of administration, the bacteria which were isolated more before administration were H. influenzae in 28.4%, S. pneumoniae in 25.7%, M. (B.) catarrhalis in 12.0% and S. aureus in 10.6%. The frequency of S. aureus after administration over 15 days was almost the same as that before administration, but the frequency of P. aeruginosa (both mucoid and non-mucoid) was 36.8% which was higher than that before administration. The frequency of isolated S. pneumoniae was decreased after administration and none of them was isolated after completion of administration. However, that of H. influenzae was decreased to 7.1% after administration within 3 days, and many H. influenzae were isolated after completion of administration as 21.4%.

Cerebrospinal fluid immunocytochemical analysis and neuroimaging in the diagnosis of primary leptomeningeal melanoma. Case report.

A 20-year-old man presented with slowly progressing symptoms indicative of increased intracranial pressure. Two weeks later he underwent surgery for placement of a ventriculoperitoneal shunt. Cytological examination of the patient's cerebrospinal fluid (CSF) revealed atypical cells that contained no detectable melanin deposits, but proved to be immunocytochemically positive for monoclonal antibodies to melanocytic cells (HMB-45) and S-100 protein. Dermatological and ophthalmological examinations failed to demonstrate any abnormalities. On the basis of these findings, a diagnosis of primary leptomeningeal melanoma was made. Gadolinium-enhanced magnetic resonance (MR) images of the brain and spinal regions obtained 2 months after admission demonstrated typical widespread leptomeningeal enhancement. Results of technetium-99m-hexakis (2-methoxyisobutyl isonitrile) single-photon emission computerized tomography (99mTc-MIBI SPECT) scanning revealed intense uptake of the isotope in the leptomeningeal regions and some cisterns. The patient's condition progressively worsened and he died 5 months after admission. The diagnosis was confirmed at autopsy. Immunocytochemical analysis of CSF performed using HMB-45 and S-100 protein antibodies is important for the diagnosis of leptomeningeal melanoma because of the test's simplicity, high specificity, and sensitivity. Gadolinium-enhanced MR imaging is used to demonstrate the extent of the leptomeningeal melanoma. An additional and supplemental neuroimaging modality, 99mTc-MIBI SPECT scanning has good potential for the detection and diagnosis of leptomeningeal melanoma.

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (1998)].

The bacteria isolated from the patients with lower respiratory tract infections were collected by institutions located throughout Japan, since 1981. Ikemoto et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and analyzed some characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In these 18 institutions around the entire Japan, 532 strains of presumably etiological bacteria were isolated mainly from the sputa of 438 patients with lower respiratory tract infections during the period from October in 1998 to September in 1999. MICs of various antibacterial agents and antibiotics were determined against 85 strains of Staphylococcus aureus, 100 strains of Streptococcus pneumoniae, 96 strains of Haemophilus influenzae, 75 strains of Pseudomonas aeruginosa (non-mucoid strains), 6 strains of Pseudomonas aeruginosa (mucoid strains), 38 strains of Moraxella subgenus Branhamella catarrhalis, 26 strains of Klebsiella pneumoniae etc., and the susceptibilities of 517 strains were assessed except for those strains that died during transportation. S. aureus strains for which MICs of oxacillin (MPIPC) were higher than 4 micrograms/ml (methicillin-resistant S. aureus: MRSA) accounted for 60.0%. Vancomycin (VCM) and arbekacin (ABK) showed the most potent activities against MRSA. But one of MRSA showed resistance to ABK with the MIC of 64 micrograms/ml. The sensitive strains of MRSA to VCM have decreased. The frequency of penicillin (PC)-intermediate S. pneumoniae (PISP) + PC-resistant S. pneumoniae (PRSP) have increased in 46.0% for 1998 comparatively from 30.9% of 1997's. But PRSP decreased, and PISP increased into 39.0% of 1998 years from 19.8% of 1997's. Panipenem (PAPM), imipenem (IPM) and faropenem (FRPM) showed the most potent activities against S. pneumoniae with MIC80s of 0.125 microgram/ml or below. Against H. influenzae and M. (B.) catarrhalis, almost all the drugs showed good activities. The sensitive strains of them against ceftazidime (CAZ) decreased in 1997, but those have increased in 1998. Inversely, the susceptibility of them against cefotiam (CTM) had been higher in 1997, but those have been lower in 1998. Tobramycin (TOB) showed the most potent activity against P. aeruginosa (both mucoid and nonmucoid strains). All drugs except ampicillin (ABPC) were active against K. pneumoniae. A quite few of K. pneumoniae showed low susceptibilities. Also, we investigated year to year changes in the characteristics of patients, their respiratory infectious diseases, and the etiology. The examination of age distribution indicated that the proportion of patients with ages over 70 years was 48.6% of all the patients showing a slight increase in every year. About the proportion of diagnosed diseases as follows: Bacterial pneumonia was the most frequent with 40.2%. The ratio of it has increased slightly, and the increased rate was 10% in patients with ages over 70 years compared with the results in 1997. Chronic bronchitis have decreased slightly with 27.6% in 1998. Number of strains isolated from patients before administration of antibiotics were more than those after administration of them in chronic bronchitis, but these were almost same number in bacterial pneumonia. Administration of antibiotics has changed the results of the frequency of isolation of bacterial species. Bacterial isolations before administration of antibiotics were as follows: S. pneumoniae 26.7%, H. influenzae 23.8%, S. aureus 13.3% and M. (B.) catarrhalis 10.8%. The frequencies of S. aureus decreased after antibiotics administration over 15 days, but the frequencies of P. aeruginosa (both mucoid and non-mucoid) was not affected. The frequencies of P. aeruginosa was 45.5% after administration over 15 days. The frequencies of S. pneumoniae decreased upon administration of antibiotics, these were only 4.5% over 15 days. The frequencies of H. (

[A case with juvenile rheumatoid arthritis who developed cerebral vasculitis and venovascular hypertension].

On November, 1997, a 15-year-old boy visited our hospital because of headache, fever and arthralgia. He was treated with 5 mg/day of prednisolone thereafter. On October 21, 1998, he was admitted because of remittent fever and multiple arthralgia and diagnosis of juvenile rheumatoid arthritis (JRA) was made. He was also found to have hypertension of 210/110 mmHg, and soon developed ptosis of the eye, facial paresis and perceptive deafness of the right side. Cerebrospinal fluid showed protein of 98 mg/dl and mildly elevated IgG, IgA and IgM levels with normal cell count. Brain MRI examination revealed multiple cerebral lesions in the frontal, parietal and cerebellar areas on the right, whose cause was thought to be vasculitis. Renal angiography demonstrated a right renal artery stenosis, compatible with renovascular hypertension. He was treated with 60 mg of prednisolone per day, which brought about a satisfactory improvement of the above rheumatic and neurologic signs. On November 17, 1998, he received a follow-up study of MRI, which failed to show any cerebral lesions, supporting the effectiveness of prednisolone. An angiotensin converting enzyme inhibitor successfully normalized hypertension and renin activity in serum, although renal blood flow did not increase.

Structural studies on polymer whiskers by transmission electron microscopy: I. Morphological and high-resolution observations.

The structures of poly(p-hydroxybenzoic acid) (PHBA) whisker crystals and crystalline fine fibrils of copolymer prepared from p-hydroxybenzoic acid (HBA) and 2-hydroxy-6-naphthoic acid (HNA), namely poly(HBA/HNA) (monomer molar ratio: 97/3), were investigated by transmission electron microscopy (TEM). As for a PHBA whisker, microfibril-like bright regions were recognized in the 210 dark-field image. In the high-resolution TEM image of another PHBA whisker, however, lattice fringes were continuous through the whisker, showing that the whisker is highly crystalline and almost perfect. On the other hand, in the high-resolution images of poly(HBA/HNA) fine fibrils, granular crystallites (20-40 nm in lateral dimension) were observed. The lattice fringes in the crystallites were not successfully indexed with the orthorhombic unit cells of the homopolymer crystal, suggesting the coexistence of another different structure as a minor component.

Extrapontine myelinolysis and behavioral change after transsphenoidal pituitary surgery: case report.

OBJECTIVE AND IMPORTANCE: Rapid correction of hyponatremia is considered the usual cause of central pontine myelinolysis and extrapontine myelinolysis. Little has been reported about mental changes associated with this disorder or its occurrence after transsphenoidal surgery. CLINICAL PRESENTATION: A 24-year-old woman suddenly developed markedly abnormal behavior associated with rapid correction of hyponatremia 11 days after undergoing transsphenoidal surgery for a prolactin-secreting pituitary adenoma. INTERVENTION: Magnetic resonance imaging and positron emission tomography with 18F-fluorodeoxyglucose showed bilateral caudate nuclei and putaminal lesions. Gradual, complete clinical resolution preceded the resolution that was revealed by magnetic resonance imaging. CONCLUSION: We emphasize the importance of cautious correction with frequent electrolyte determinations and attention to behavioral changes in the management of delayed hyponatremia after pituitary tumor surgery.

[A case of systemic lupus erythematosus developed with intestinal perforation].

A case of intestinal perforation associated with SLE is presented. A 54-year-old woman was diagnosed as having SLE twenty-five years ago when she had facial erythema, photosensitivity, oral aphtha, polyarthraliga, leukopenia, positive LE cell and positive antinuclear antibody. She had been treated with prednisolone and admitted to Kushiro City General Hospital because of one month history of fever and anorexia in February 1996. Laboratory findings did not reveal activity of SLE, and a diagnosis of urinary tract infection was made based on the findings of urinalysis. After severe diarrhea, disseminated intravascular coagulation (DIC) developed. A rectal perforation was revealed by endoscopic and radiological examination. An emergency laparotomy revealed necrosis of the rectum and sigmoidostomy was performed. The biopsied specimen of the rectum were diagnosed as gangrene of ischemic colitis histologically. Because of a penetration to the urinary bladder, an ureterocutaneostomy was performed. She died of sepsis and DIC on the 127th day of admission. Only 11 cases of intestinal perforation associated with SLE have been reported in Japan, and the association of vasculitis has been considered. In the present case, the prolonged use of prednisolone might cause the necrotizing ischemic colitis.

Genetic polymorphisms and alternative splicing of the hOGG1 gene, that is involved in the repair of 8-hydroxyguanine in damaged DNA.

The hOGG1 gene encodes a DNA glycosylase that excises 8-hydroxyguanine (oh8Gua) from damaged DNA. Structural analyses of the hOGG1 gene and its transcripts were performed in normal and lung cancer cells. Due to a genetic polymorphism at codon 326, hOGG1-Ser326 and hOGG1-Cys326 proteins were produced in human cells. Activity in the repair of oh8Gua was greater in hOGG1-Ser326 protein than in hOGG1-Cys326 protein in the complementation assay of an E. coli mutant defective in the repair of oh8Gua. Two isoforms of hOGG1 transcripts produced by alternative splicing encoded distinct hOGG1 proteins: one with and the other without a putative nuclear localization signal. Loss of heterozygosity at the hOGG1 locus was frequently (15/ 23, 62.2%) detected in lung cancer cells, and a cell line NCI-H526 had a mutation leading to the formation of the transcripts encoding a truncated hOGG1 protein. However, the oh8Gua levels in nuclear DNA were similar among lung cancer cells and leukocytes irrespective of the type of hOGG1 proteins expressed. These results suggest that the oh8Gua levels are maintained at a steady level, even though multiple hOGG1 proteins are produced due to genetic polymorphisms, mutations and alternative splicing of the hOGG1 gene.