Cerebral metabolism of oxygen and glucose in a patient with MELAS syndrome

We studied cerebral oxygen and glucose metabolism as well as cerebral blood flow using positron emission tomography (PET) in a case with MELAS showing dementia, diabetes mellitus, ataxia and lactic acidosis without any signs of stroke. This case, confirmed to have a point mutation at position 3243 in the transfer RNA gene of mitochondrial DNA, developed a stroke-like episode 8 months after the PET study. Uncoupling was observed between cerebral oxygen metabolism and cerebral blood flow with reduced fractional oxygen extraction ratio, indicating "hyperemia", not ischemia. The "hyperemia" may be closely related to the malfunction of mitochondria in aerobic energy production. A drastic decrease in cerebral oxygen metabolism (CMRO2) was found globally in contrast to preserved cerebral glucose metabolism (CMRglu), resulting in a remarkable decrease in the metabolic ratio (CMRO2/CMRglu). The dissociation between cerebral glucose and oxygen metabolism may be characteristic of MELAS.

[A surgically treated case of ventrally exophytic pontine glioma]

A surgically treated case of ventrally exophytic pontine glioma is reported. A 49-year-old woman, complaining of dysarthria, dysphagia and gait disturbance, was admitted to our department. Her past history included bronchial asthma. Plain skull x-p and tomography revealed destruction of the dorsum sellae and upper clivus. CT demonstrated an enhanced oval mass at the ventral side of the upper brainstem. The mass was severely compressing the brainstem dorsally. MRI revealed a low-intensity band between the tumor and the brainstem. Dynamic MRI demonstrated a pattern of rapid increasing and slow reduction. Cerebral angiogram demonstrated a paradoxical sign that pontine branches were located anterior to the basilar artery. The finding demonstrated that the tumor was an intraaxial mass. The first operation was performed by the orbitofrontomalar approach. On the trans-sylvian route, the tumor was removed partially with CUSA and neuronavigation system. Its histology was astrocytoma grade III. Radiation therapy was added. The patient's symptoms aggravated again. On the second operation, the transtemporal route with tentorial resection was chosen. Under a wide visual field, intracapsular subtotal resection of the tumor was performed. Interferon therapy was added. She was discharged to her home with no neurological deficits. Ventrally exophytic pontine glioma is very rare. Low-intensity band of MRI, a sign of extraaxial mass, was visualised in our case. On the other hand, cerebral angiogram demonstrated a paradoxical sign. This sign suggested that the tumor originated from the brainstem. With update skull base surgery and neuronavigation system, surgical therapy of ventrally exophytic pontine glioma is safe and effective.

The chronological change of vertebral bone loss following oophorectomy using dual energy X-ray absorptiometry: the correlation with specific markers of bone metabolism

The changes of vertebral bone mineral density (BMD; g/cm2) following oophorectomy were studied, using dual energy X-ray absorptiometry (DEXA) in 38 premenopausal and 244 oophorectomized women. Two biochemical indices of bone remodeling, urinary deoxypyridinoline (DPyr) for bone resorption and serum intact human osteocalcin (hOC) for bone formation, were also measured at the same time. The rate of bone loss in the first year after oophorectomy was 10.7%, while that in the second year was 5.7% (rapid phase), followed by a slow phase at the rate of 1.1%. The bone mass finally reached an osteoporotic level (BMD < 0.767 g/cm2) at 12 years after oophorectomy. The DPyr increased to reach a peak level in the first year, whereas the hOC increased and reached its peak level in the second year after surgery. The maximal bone loss in the first year is considered to be caused by the remarkable increase of bone resorption and the biological delay of the maximal increase in bone formation.

Effect of a new dual neurokinin antagonist on airway smooth muscle in situ

The effect of FK224 (N-(N2-[N-¿N-(N-2,3-didehydro-N-methyl-N-[N-3- (2-pentylphenyl)-propionyl¿-L-threonyl]tyrosyl-L-leucynyl)-D -phenylalanyl¿-L-allothreonyl]-L-asparaginyl)-L-serine-v-lacto ne, CAS 125787-94-2) on isometric contraction of canine tracheal smooth muscle in situ was studied. Contraction was induced by administration of substance P, neurokinin A, and neurokinin B intra-arterially into the tracheal circulation in five mongrel dogs. FK224 inhibited substance P- and neurokinin A-induced contraction in a dose-dependent manner, but it did not inhibit neurokinin B-induced contraction significantly. These data suggest that FK224 is a dual antagonist of both neurokinin 1 and neurokinin 2 receptors, with a similar potency in in vivo experiments.

The determination of clinically meaningful cognitive decline: development and use of an alternative method

Statistical methods traditionally used in the analysis of change (e.g., repeated measures ANOVA) may be inadequate for the investigation of cognitive decline if a study's effect size is small, the variance within groups is heterogeneous, or the statistical power is low. To examine an alternative approach to the determination of clinically meaningful cognitive decline and investigate whether such decline occurs during the first year after stroke, we administered a neuropsychological test battery to 172 patients (age = 70.3 +/- 7.6 years; education = 10.3 +/- 4.7 years) 3 and 12 months after stroke and 199 nondemented stroke-free control subjects (age = 71.1 +/- 6.4 years; education = 12.8 +/- 4.2 years) on two occasions 12 months apart. Two neuropsychologists classified each subject's test performance as having declined, improved, or remained stable based solely on clinical judgment. Reliability of the rating of decline versus the pooled rating of improvement/stability was excellent (kappa = 0.79). The two rating groups differed significantly and in the appropriate directions in change on most tests. While a MANOVA comparing the stroke and control groups on change in test scores was not significant, logistic regression analysis determined that a rating of clinically meaningful cognitive decline was associated with stroke status (Odds Ratio = 1.8, 95% Confidence Interval = 1.0 to 3.2), while adjusting for demographic factors. We propose that this alternative approach to the analysis of cognitive change can facilitate the recognition of decline in subgroups of subjects. It would be valuable as an adjunct to studies of the incidence of dementia, for example, in which the recognition of cognitive decline might be difficult in highly educated patients whose baseline level of performance is far above the cutoffs operationalized for the diagnosis of dementia.

A standardized technique for establishing onset and duration of symptoms of Alzheimer's disease

OBJECTIVES

To develop an informant-based semistructured interview to determine the onset and duration of symptoms of Alzheimer's disease, and to use this instrument with informants to characterize a cohort of mildly impaired patients with Alzheimer's disease.

DESIGN

In study 1, interrater and interinformant reliability was examined for the date of onset and the order of appearance for specific symptoms that were elicited by the semistructured onset interview. In study 2, the instrument was used to characterize disease onset in a cohort of patients with Alzheimer's disease who were participating in a large multicenter study.

SUBJECTS

Informants of patients with Alzheimer's disease.

RESULTS

In study 1, interrater reliability for duration of illness was excellent (intraclass correlation coefficient = .99, P < .001), and interinformant reliability was good (intraclass correlation coefficient = .86, P < .001). Agreement for the presence of a given symptom was highest for those that were most commonly reported (eg, memory and performance difficulty). In study 2, 89% of the cohort had memory problems, and 63.9% had performance difficulties as the first or second symptom. Depression and language problems were less commonly reported. Psychosis and behavioral disturbances were rarely reported as the first problem.

CONCLUSION

This instrument provides a reliable procedure for standardizing the estimation of duration of illness based on retrospective report.

Neuropsychological characteristics of preclinical dementia in Parkinson's disease

The goal of this study was to characterize the changes in cognition associated with the earliest, or preclinical, stages of dementia in Parkinson's disease (PD). We administered a comprehensive neuropsychological test battery to a group of initially nondemented PD patients participating in a longitudinal community-based epidemiologic study. We used Cox proportional hazards models to assess the relative risk of incident dementia associated with baseline scores on the neuropsychological tests. Baseline performance on two verbal fluency tasks (letter fluency and category fluency) was significantly and independently associated with incident dementia. Tests of memory, orientation, abstract reasoning, naming, and constructional skill were less sensitive predictors of subsequent dementia. The neuropsychological pattern characterizing the preclinical stages of dementia in PD differed from that described previously in preclinical Alzheimer's disease. Results suggest that poor performance on tests of verbal fluency may represent a distinct characteristic of the preclinical phase of dementia in PD.

The activation and nuclear translocation of extracellular signal-regulated kinases (ERK-1 and -2) appear not to be required for elongation of neurites in PC12D cells

The outgrowth of neurites was induced in PC12D cells, a subline of PC12 cells, that were treated not only with NGF but also with dbcAMP, staurosporine or bFGF. Simultaneous activation and rapid nuclear translocation of MAP kinases (ERK-1 and ERK-2) were observed in cells treated with NGF or bFGF. But staurosporine and dbcAMP induced no or only slight activation of the kinases. The nuclear translocation of the MAP kinases was not induced by the latter agents. These observations suggest a close relationship between the activation and the nuclear translocation of MAP kinases and, moreover, that stimulation and relocalization of MAP kinases might not be required for the outgrowth of neurites from PC12D cells. Staurosporine and dbcAMP may stimulate a down-stream step of the NGF pathway, or a parallel pathway(s) to the MAP kinase cascade in promoting neurite formation from PC12D cells. These agents mimic the effects of NGF in promoting neurite outgrowth in cultured sympathetic neurons, but not in conventional PC12 cells. Because of the similarity between PC12D cells and primed cells, it seems possible that activation and nuclear translocation of MAP kinases might be required for the transcription-dependent differentiation step but might not be necessary for the elongation of neurites at least in response to staurosporine or to dbcAMP.

[A case of complex brain anomaly with arachnoid cyst treated well by cyst-cisternal shunt]

A rare case of complex anomaly, composed of schizencephaly, polymicrogyria, heterotopic gray matter, agenesis of the septum pellicidi and arachnoid cyst at the right middle cranial fossa was encountered. A 38-year old man, complaining of epileptic seizure, was admitted to our department. His past history included cerebral palsy. Plain skull roentgenogram showed protrusion of the right temporal bone and thinning of the ipsilateral sphenoidal wing. CT revealed arachnoid cyst and parietal crest surrounded by cortical layer on the right side. MRI also demonstrated the arachnoid cyst, parietal crest and agenesis of septum pellicidi. MRI, especially proton density weighted image, well demonstrated cortical layer surrounding the parietal crest, right opercular polymicrogyria and left heterotopic gray matter. The crest was diagnosed as schizencephaly. The arachnoid cyst was treated by cyst-cisternal shunt with a silicone tube (Sapporo shunt) after fenestrating the cyst. The tube was inserted into the sylvian fissure from the cyst and sutured to the inner wall of the cyst. Despite slight intratumoral hemorrhage in the CT at 1.5 months after the operation, the cyst markedly decreased in size. As to the diagnosis of the brain anomaly, MRI gives extremely useful information. Particularly for the diagnosis of anomalies of migration of neuronal cells, MRI, especially proton density weighted image, has been regarded as an indispensable examination. In the operation of subarachnoid cyst, to maintain the flow between the inside of its cyst and the basal cistern, cyst-cisternal shunt with a silicone tube had satisfactory results.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of hemorrhagic mixed cerebrovascular malformation of the brainstem draining through a transpontine vein]

A case of mixed cerebrovascular malformation of the brainstem with pontine hemorrhage is reported. The mixed cerebrovascular malformation was composed of medullary venous malformation, one hemorrhagic and another non-hemorrhagic mass. The latter masses were thought to be cavernous venous malformations by their MR findings. The medullary venous malformation drained to the anterior pontomesencephalic vein through a transpontine vein. A 70-year-old man, complaining of aggravation of left hemiparesis, was admitted to our department. His past history included traumatic cervical myelopathy and diabetic neuropathy. CT revealed a pontine hemorrhage with linear enhancement. Depending on MRI findings, the hemorrhage was thought to be an intratumoral hemorrhage within the cavernous venous malformation. Cerebral angiogram demonstrated medullary venous malformation. The malformation drained to the anterior pontomesencephalic vein through a transpontine vein. The linear enhancement was the transpontine vein itself. Medullary venous malformations in the brainstem are rare. With MRI, the transpontine vein is thought to be a characteristic feature of medullary venous malformation of the brainstem. We suggest that most cases of hemorrhagic medullary venous malformations are mixed cerebrovascular malformations. We emphasize the need for precise examination of other types of vascular lesions coexisting with medullary venous malformations.

Site-specific effects of testosterone propionate on the prostate of rat pretreated with 3,2'-dimethyl-4-aminobiphenyl: dose-dependent induction of invasive carcinomas

It has been shown that testosterone propionate (TP) strongly promotes induction of invasive carcinomas in previously initiated accessory sex organs. In this study, in order to clarify the dose-dependence of this promotion, TP was given at 3 different levels (high, medium or low doses) using different sizes (2, 1 and 0.5 cm long) of Silastic tube for 40 weeks after administration of 3,2'-dimethyl-4-aminobiphenyl to male F344 rats. The data showed development of invasive carcinomas in the dorso-lateral and anterior prostate and in the seminal vesicle to be dose-dependent with the high dose of TP being most effective for tumor induction. Average levels of serum testosterone were approximately 800, 600, 300 and 150 ng/dl in rats given the high to low doses and in control rats, respectively. Development of neoplastic lesions in the ventral prostate demonstrated an inverse dependence on the dose of TP. These findings, together with previous data, suggest that the tumor-promoting potential of TP on rat prostate is unlikely to be simply due to its androgenic action and other factors should also be considered.

Effect of tea (Camellia sinensis L.) on lipid peroxidation in rat liver and kidney: a comparison of green and black tea feeding

The antioxidant effects in the liver and kidney obtained from rat fed diets containing 3% green or black tea leaf powder, which were prepared from the same lot tea leaves, were studied using the tissue slice-antioxidant evaluation method with two lipid peroxidation inducers. After 50 d on the diets, liver slices prepared from green and black tea-supplemented rats showed significant inhibitory effects against tert-butyl hydroperoxide-induced lipid peroxidation. These effects, however, were not proportional to the amounts of (-)-epicatechins and antioxidant vitamins in the tea leaves. In the kidney, the antioxidant effect was observed only in the green tea-fed group. A similar antioxidant effect on the kidney was observed after oral administration of a major tea polyphenol, (-)-epigallocatechin gallate (50 mg/kg body weight for 7 d). Liver slices from black tea-fed rats also inhibited bromotrichloromethane-induced lipid peroxidation. These results demonstrated that dietary green and black tea had antioxidant effects on tissue lipid peroxidation ex vivo.

[A hemodialysis patient with HTLV-1-associated myelopathy (HAM)]

We report here a case of maintenance hemodialysis with HTLV-1 associated myelopathy (HAM). A 53-year-old female hemodialysis patient was admitted to Teikyo University Ichihara hospital because of paralytic ileus. She had a history of blood transfusion and had been under dialysis treatment for 8 years. She had experienced gait disturbance and sensory disturbance in her lower extremities for 8 years. Neurological examination revealed myelopathy and neuropathy. Laboratory data revealed that serum anti-HTLV-1-antibody was over 1260 x (PA) and liquor HTLV-1-antibody was over 160 x (PA). Her liquor revealed a cell count of 4/3 cmm, protein 22 mg/dl, glucose 45 mg/dl, chloride 125 mEq/l and no atypical cells. To the best of our knowledge this is a rare case in Japan. Our findings suggest that HAM should be taken into consideration when we diagnose a maintenance hemodialysis patient showing neuropathy and myelopathy.

Neuropsychological detection and characterization of preclinical Alzheimer's disease

We attempted to characterize the changes in cognition associated with the earliest, or preclinical, stages of Alzheimer's disease (AD) by administering a comprehensive neuropsychological test battery to a group of initially nondemented older adults participating in a prospective epidemiologic study of dementia. Using Cox regression analyses, we examined the associations between baseline neuropsychological test scores and subsequent development of AD. Results confirmed preliminary findings that baseline scores on the Boston Naming Test, Immediate Recall on the Selective Reminding Test, and the Similarities subtest of the Wechsler Adult Intelligence Scale-Revised were significantly and independently associated with later diagnosis of AD. Analyses controlled for the effects of age, education, sex, and language of test administration. These results lend support to the notion of a preclinical phase of AD and indicate that this very early stage of AD is characterized by poor word-finding ability, abstract reasoning, and memory.

Lack of carcinogenicity of monosodium L-glutamate in Fischer 344 rats

Monosodium L-glutamate (MSG) was administered to groups of 50 male and 50 female Fischer 344 rats in the diet at levels of 0, 0.6, 1.25, 2.5 and 5.0% for a 2-yr period. Survival of dosed and control rats of both sexes was comparable, although animals receiving 5.0% MSG showed a trend towards (or significant) growth retardation. Urinary biochemistry values indicated increased pH and Na+ levels and decreased K+ in rats of both sexes given 2.5 or 5.0%. However, no significant increases in proliferative or neoplastic lesion development in the urinary tract were observed in any MSG-treated animals. In addition, occurrences of neoplastic lesions in other organs did not differ between treated and control groups. The present study thus did not demonstrate any long-term carcinogenic effect of MSG administered to rats at levels up to 5.0% in the diet.

Neuropsychologic impairment in early HIV infection. A risk factor for work disability

OBJECTIVE

To explore the functional significance of incident neuropsychologic impairment among initially asymptomatic subjects infected with human immunodeficiency virus.

DESIGN

Prospective, observational cohort study of homosexual and bisexual men to examine the incidence of work disability related to the onset of neuropsychologic impairment.

SETTING

A university clinical and behavioral research site in New York City.

PARTICIPANTS

Sample of 207 homosexual and bisexual men; 123 were seropositive and 84 were seronegative. PRINCIPAL OUTCOME MEASURES: Incident work disability in the course of 4.5 years of follow-up, with disability defined as a persistent (> or = 24 months) change in work hours (from 20 or more to less than 20 h/wk).

RESULTS

Compared with seronegative control subjects (n = 72), the relative risk of work disability among initially asymptomatic seropositive men (n = 44) was 2.76 (95% confidence interval, 1.2 to 6.5), nearly a threefold increase. Proportional hazards models show that this increased risk is attributable to the development of major neuropsychologic impairment in a subset (eight of 44) of the initially asymptomatic men, which is significantly associated with incident work disability (6/8 [75%]). Adjusting for symptom status and CD4+ cell count at the time of disability did not eliminate the increased risk associated with neuropsychologic impairment.

CONCLUSIONS

In this cohort, the increased risk of work disability among initially asymptomatic human immunodeficiency virus-positive men was related to incident neuropsychologic impairment; such impairment predicted work disability independently of symptom status and CD4+ cell count over the follow-up period. Neuropsychologic impairment in the course of human immunodeficiency virus infection may indicate increased risk for poor outcomes over and above that associated with systemic disease.

[Peripheral T-cell lymphoma with abundant ATL-like cells in the blood]

A 69-year-old woman was admitted to our hospital because of leucocytosis and systemic lymphadenopathy. On admission, white blood cell count was 163,000/microliters, most of which consisted of flower-like cells with convoluted nuclei in the peripheral blood. In the abnormal lymphocyte cells surface-marker test by flow cytometry showed that they expressed CD2, CD3, CD4, CD29, CD45RA, and CD38, but not CD8, CD16, and CD25. Serum anti-Human T-lymphotropic virus type-I (HTLV-I) antibody was negative in particle agglutination, enzyme-linked immunosorbent assay (ELISA) and western-blotting assay. HTLV-I proviral DNA in the abnormal lymphocyte cells was not detected by southern blotting hybridization technique. Moreover, HTLV-I provirus was not detected using a polymerase-chain-reaction (PCR). A monoclonal rearrangement of the TCR-beta chain gene was evident by using DNA probe in southern blot hybridization. Because of the rapid progress of the disease, chemotherapy was started immediately after admission. Though, this patient became refractory, and she died about 1 year after admission.

Neuropsychological changes in a prospectively followed cohort of homosexual and bisexual men with and without HIV infection

We evaluated neuropsychological test performance of 168 homosexual and bisexual men with and without human immunodeficiency virus (HIV) infection (113 HIV+ subjects and 55 HIV- controls) over 4.5 years of semiannual follow-up. Analyses of the longitudinal data were performed by applying generalized estimating equations (GEEs) to regression analyses with repeated measures. Compared with the HIV- men, the HIV+ subjects performed more poorly on memory testing. Performance on all tests tended to improve over time, but this improvement was attenuated or eliminated in the HIV+ group for tests of language and attention. Within the HIV+ subjects, improvement over time in tests of memory, executive function, language, and attention was attenuated or eliminated in patients with lower CD4 levels; more advanced HIV disease was associated with poorer memory and executive function and with attenuated or reduced learning effects for memory, motor speed, and language tests. Clinically significant neurologic findings were associated with worse memory and orientation and with attenuated or reversed learning effects for memory, language, and attention tests. There were 33 deaths in the HIV+ group. In the men who died, there was more rapid decline in executive, language, and attentional test performance. These observations remained significant after controlling for HIV disease severity. We conclude that HIV infecting the CNS results in progressive cognitive change that is closely associated with neurologic findings. In addition, our findings suggest a relation between more rapid cognitive progression and death.

Modification by analgesics of lesion development in the urinary tract and various other organs of rats pretreated with dihydroxy-di-N-propylnitrosamine and uracil

Effects of the analgesics phenacetin, acetaminophen and antipyrine on lesion development in the urinary tract and other organs in male F344 rats were investigated. Animals were concurrently administered with 0.1% dihydroxy-di-N-propylnitrosamine (DHPN) in drinking water and 3.0% uracil in the diet for 4 weeks and then, starting 1 week after the cessation of this treatment, received basal diet or diet containing phenacetin, acetaminophen or antipyrine for 35 weeks. The occurrences of renal cell tumors were increased in the groups given phenacetin or antipyrine, as compared with the DHPN + uracil alone controls. Antipyrine, but not the two other compounds, also enhanced development of hyperplastic lesions in the renal pelvis and ureter. In the urinary bladder, phenacetin and antipyrine treatments were both associated with increased incidence of preneoplastic or neoplastic lesions. Furthermore, phenacetin alone, without the initiating agent pretreatments, induced simple hyperplasias of the urinary bladder at high incidence. Antipyrine enhanced induction of hyperplastic lesions in the ureter and was also found to increase the incidences of preneoplastic and neoplastic lesions in the liver. Although decreased incidences of tumor development of lung and thyroid were observed for the group given phenacetin, this might have been linked to the decreased weight gain. The results confirmed that combination treatment with DHPN + uracil is effective for wide-spectrum initiation of carcinogenesis in the urological tract and demonstrated significant modification potential for both phenacetin and antipyrine.