Treatment of persistent sleep-wake schedule disorders in adolescents with methylcobalamin (vitamin B12).

Two adolescent patients suffering from persistent sleep-wake schedule disorders appear to have responded to treatment with vitamin B12 (methylcobalamin). A 15-year-old girl with delayed sleep phase syndrome (DSPS) and a 17-year-old boy with hypernychthemeral syndrome complained of not being able to attend school despite many trials of medication. The improvement of the sleep-wake rhythm disorders appeared immediately after the administration of high doses (3,000 micrograms/day) of methylcobalamin. Neither patient showed any laboratory or clinical evidence of vitamin B12 deficiency or hypothyroidism (which can cause B12 deficiency). Serum concentrations of vitamin B12 during treatment were in the high range of normal or above normal. The duration of the sleep period of the DSPS patient decreased gradually from 10 hours to 7 hours, and the time of sleep onset advanced from 2 a.m. to midnight. The period of the sleep-wake cycle of the hypernychthemeral patient was 24.6 hours before treatment and 24.0 hours after treatment. The relationship between the circadian basis of these disorders and vitamin B12 and its metabolites is discussed.     

Hyperplastic epithelial foci in honeycomb lesions in idiopathic pulmonary fibrosis

Seventy-two cases of idiopathic pulmonary fibrosis (IPF) were examined from 2856 consecutive autopsy cases at the Japanese Red Cross Medical Center in Tokyo from 1973-1996. Primary lung cancer had arisen in 31 of 72 cases of IPF (43%), significantly higher than the incidence in cases without IPF (8.1%) and in the cases with non-IPF chronic lung diseases (11.9%). Hyperplastic epithelial foci in the honeycomb lesions of IPF cases were significantly more prominent in the lower than in the upper lobe, in cases with or without lung cancer, and they were more prominent in the lower lobe of IPF with than in those without cancer. The length of hyperplastic epithelial foci in the lower lobe of IPF cases was longer than that in interstitial pneumonia-associated with collagen vascular diseases. There was a higher PCNA labeling index of hyperplastic epithelial foci in IPF cases than in cases of interstitial pneumonia-associated with collagen vascular diseases. The PCNA labeling index was almost the same between smokers and nonsmokers with IPF. Overexpression of p53 was observed in hyperplastic epithelial foci in honeycomb lesion of IPF. DNA ploidy analysis of hyperplastic epithelial foci in the paraffin sections of 12 IPF cases revealed aneuploidy patterns in eight cases. These results strongly suggest that accelerated cell proliferation occurs in the honeycomb lesion of IPF, and that regenerative epithelia becomes susceptible to carcinogenic agents in addition to the smoking effect.     

Genetic Structure of Spatial and Verbal Working Memory

Working memory (WM) encompasses both short-term memory (storage) and executive functions that play an essential role in all forms of cognition. In this study, the genetic structure of storage and executive functions engaged in both a spatial and verbal WM span task is investigated using a twin sample. The sample consists of 143 monozygotic (MZ) and 93 dizygotic (DZ) Japanese twin pairs, ages 16 to 29 years. In 155 (87 MZ, 62 DZ) of these pairs, cognitive ability scores from the Kyodai Japanese IQ test are also obtained. The phenotypic relationship between WM and cognitive ability is confirmed (r = 0.26–0.44). Individual differences in WM storage and executive functions are found to be significantly influenced by genes, with heritability estimates all moderately high (43%–49%), and estimates for cognitive ability comparable to previous studies (65%). A large part of the genetic variance in storage and executive functions in both spatial and verbal modalities is due to a common genetic factor that accounts for 11% to 43% of the variance. In the reduced sample, this common genetic factor accounts for 64% and 26% of the variance in spatial and verbal cognitive ability, respectively. Additional genetic variance in WM (7%–30%) is due to modality specific factors (spatial and verbal) and a storage specific factor that may be particularly important for the verbal modality. None of the variance in cognitive ability is accounted for by the modality and storage genetic factors, suggesting these may be specific to WM.     

Light and electron microscopic analyses of immediate and late tissue damage caused by radiofrequency ablation in porcine liver

Radiofrequency ablation (RFA) is an effective procedure for localized hepatocellular carcinoma. Contrast-enhanced CT depicts the ablated area as a hypoattenuated area without hepatic blood flow; however, light microscopy does not show obvious necrosis in the ablated area. We evaluated liver tissue changes after RFA by light microscopy and electron microscopy. The normal livers of three anesthetized pigs were coagulated using RFA after laparotomy. The liver was examined immediately, and 1 week after operation by light and electron microscopy. After RFA, the liver parenchyma surrounding the needle electrode was brown in color and surrounded by a red marginal zone separate from the normal liver parenchyma. Hematoxylin-eosin staining of the central area did not show cell necrosis, and the structures of liver sinusoids, liver cell cord and the nuclei of hepatocytes were preserved. However, electron microscopic examination of tissue immediately after RFA showed destruction of mitochondria of hepatocytes and fixation of sinusoidal cells. One week later, there was a large quantity of debris in the enlarged sinusoids, in addition to irreversible destruction of hepatocyte organelles. RFA of the porcine liver causes hepatocyte damage. This damage was not evident by light microscopy but clearly identified by electron microscopy.     

Peroxyl radical scavenging capability of fish sauces measured by the chemiluminescence method

Oxygen-related free radicals have been suggested as a cause of aging and various diseases, for example, various cancers and rheumatoid arthritis. A radical scavenger as an antioxidant has been sought in foods. Fish sauces are traditional Asian fermented seasonings. Using the luminol chemiluminescence method, the peroxyl radical scavenging capability of fish sauces was examined. From the IC50 values, many fish sauces have been shown to have a strong scavenging capability as well as soy sauces. A scavenging mechanism is also proposed.     

Southern hybridization analysis of DNA polymorphism in the HLA-D region

Restriction fragment-length polymorphisms (RFLP) were systematically analyzed by Southern hybridization with restriction endonuclease-digested genomic DNA from 28 HLA-homozygous B cell lines with Dw1-Dw19 specificity using the DR beta and DQ beta chain cDNAs as probes. These probes detected polymorphic fragments unique to each HLA-DR specificity. Furthermore, the DQ beta chain probes permitted us to distinguish between different Dw specificities with an identical DR type much more efficiently than with the DR beta chain probe. Distribution analysis of restriction fragments hybridizing to DR beta in relation to the DR and DQ specificities showed several sets of them forming ten clusters, some of which correlate with DRw53, DQw1, and DR alleles. This DNA typing technique allows the direct definition of HLA types at the gene level and provides a powerful tool for isolating genes controlling HLA-associated diseases.     

Pneumocystis carinii carriage in immunocompromised patients with and without human immunodeficiency virus infection

Eighty-one bronchoalveolar lavage (BAL) specimens obtained from 26 HIV-infected, 45 non-HIV immunosuppressed and 10 immunocompetent patients with primary pulmonary diseases were analysed for the presence of Pneumocystis carinii by staining and by P. carinii 5S rDNA determined by PCR. P. carinii was observed by staining of BAL specimens from HIV-infected patients significantly more frequently than those from immunocompromised hosts without HIV infection (57.7% versus 20.0%, respectively). P. carinii 5S rDNA was detected by PCR assay in seven (26.9%) HIV-infected individuals, which was significantly more frequent than for four (8.9%) immunosuppressed patients without HIV infection, for whom staining was negative. None of these patients developed P. carinii pneumonia (PCP) within the follow-up period. BAL specimens from 10 immunocompetent patients with pulmonary disorders were negative for PCP by both staining and PCR assay.     

Age-related changes in the levels of voltage-dependent calcium channels and other synaptic proteins in rat brain cortices

Neurotransmitter release from synapses is one of the most important interneuronal signaling in the nervous system. We previously reported that aging decreases depolarization-induced acetylcholine release in rat brain synaptosomes. To investigate the mechanisms underlying the age-related decrements of neurotransmission, we determined the levels of the alpha1 subunit proteins of voltage-dependent calcium channels (VDCCs) and three synaptic proteins that relate to exocytotic processes using synaptosomes prepared from cerebral cortices of young (6-month-old) and aged (27-month-old) rats. Immunoblotting analyses revealed that the protein levels of alpha1A (P/Q-type) and alpha1B (N-type) subunits in aged rats were 38% and 43% lower than the levels of young rats, respectively, but the levels of the alpha1C (L-type) subunit were not different between young and aged. On the contrary, the levels of synaptotagmin-1, synaptophysin and syntaxin were not significantly different between the two age groups in the synaptosomal preparations. These results suggest that synaptic density does not change much in the cerebral cortex in normal aging, and that the reduction of P/Q-type and N-type VDCCs, both of which participate in neurotransmitter release, is one of the causes for the decrease of neurotransmission at aged synapses.     

CC chemokine receptor 4 ligand production by bronchoalveolar lavage fluid cells in cigarette-smoke-associated acute eosinophilic pneumonia

We examined the production of macrophage-derived chemokine (MDC/CCL22) and thymus- and activation-regulated chemokine (TARC/CCL17) by bronchoalveolar lavage fluid (BALF) cells in cigarette-smoke-associated acute eosinophilic pneumonia (CS-AEP). The CC Chemokine Receptor 4 (CCR4) ligand levels in BALF from patients with CS-AEP were considerably higher than those in healthy volunteers and correlated well with Th2 cytokine levels. Interleukin-4 enhanced CCR4 ligand production. MDC expression was observed in CD68-positive cells from patients with CS-AEP and in healthy control smokers. In contrast, TARC expression in CD68- or CD1a-positive cells was detected only in CS-AEP. An in vivo cigarette smoke challenge test induced increases in CCR4 ligands in the BALF and in the cultured supernatant of BALF adherent cells. These results suggest that alveolar macrophages and dendritic cells contribute to the pathogenesis of CS-AEP by generating CCR4 ligands, probably in response to cigarette smoke.