Citations

AbstractThree Korean girls with ethylmalonic encephalopathy, the first Asian cases, were identified. In all three cases, we observed slight improvement in motor functions, cognitive behaviours and chronic mucoid diarrhoea after treatment with riboflavin and/or coenzyme Q10 treatment. The precise pathogenesis of ethylmalonic encephalopathy has not been fully elucidated, but riboflavin treatment may be helpful.

Diadenosine tetraphosphate (Ap4A) has been recently discovered in the pancreatic γ cells where targets ATP-sensitive K+ (KATP) channels, depolarizes the cell membrane and induces insulin secretion. However, whether Ap4A inhibit pancreatic KATP channels by targeting protein channel complex itself was unknown. Therefore, we coexpressed pancreatic KATP channel subunits, Kir6.2 and SUR1, in COS-7 cells and examined the effect of Ap4A on the single channel behavior using the inside-out configuration of the patch-clamp technique. Ap4A inhibited channel opening in a concentration-dependent manner. Analysis of single channels demonstrated that Ap4A did not change intraburst kinetic behavior of KATP channels, but rather decreased burst duration and increased between-burst duration. It is concluded that Ap4A antagonizes KATP channel opening by targeting channel subunits themselves and by keeping channels longer in closed interburst states.

Acute vascular or humoral rejection, a vexing outcome of organ transplantation, has been attributed by some to activation and by others to apoptosis of endothelial cells in the graft. We asked which of these processes causes acute vascular rejection by tracing the processes during the development of acute vascular rejection in porcine cardiac xenografts performed in baboons. Apoptosis, assayed by terminal deoxynucleotidyl transferase–mediated dUTP nick end-labeling (TUNEL), expression of activated caspase-3, and proapoptotic genes Bax and Bcl-x L , was not detected until acute vascular rejection was well advanced, and even then, apoptosis was largely confined to myocytes. Activation of the endothelium, as evidenced by expansion of rough endoplasmic reticulum and increased ribosomal antigen and phospho-p70 S6 kinase, occurred early in the course of acute vascular rejection and progressed through the disease process. These findings suggest that acute vascular rejection is caused by an active metabolic process and not by apoptosis in the endothelium.

Cardiac fibroblasts (CFs) produce extracellular matrix proteins and participate in the remodeling of the heart. It is unknown if brain natriuretic peptide (BNP) is synthesized by CFs and if BNP participates in the regulation of extracellular matrix turnover. In this study, we examined the production of BNP in adult canine CFs and the role of BNP and its signaling system on collagen synthesis and on the activation of matrix metalloproteinases (MMPs). BNP mRNA was detected in CFs, and a specific radioimmunoassay demonstrated that BNP 1-32 was secreted into the media at a rate of 11.2±1.0 pg/10 5 cells per 48 hours (mean±SEM). The amount of BNP secretion was significantly ( P <0.01) augmented by 10 −7 mol/L tumor necrosis factor-α in a time-dependent manner. BNP significantly ( P <0.01) inhibited de novo collagen synthesis as assessed by [ 3 H]proline incorporation, whereas zymographic MMP-2 (gelatinase) abundance was significantly ( P <0.05) stimulated by BNP between 10 −7 and 10 −6 mol/L. In addition, protein expression of MMP-1, -2, and -3 and membranous type-1 MMP was significantly increased by 10 −6 mol/L BNP. The cGMP analogue 8-bromo-cGMP (10 −4 mol/L) mimicked the BNP effect, whereas inhibition of protein kinase G by KT5823 (10 −6 mol/L) significantly ( P <0.05) attenuated BNP-induced zymographic MMP-2 abundance. In summary, this study reports that BNP is present in cultured CFs and that BNP decreases collagen synthesis and increases MMPs via cGMP–protein kinase G signaling. These in vitro findings support a role for BNP as a regulator of myocardial structure via control of cardiac fibroblast function.

This study is the third in a series that has explored the source of intelligibility decrement in dysarthria by jointly considering signal characteristics and the cognitive–perceptual processes employed by listeners. A paradigm of lexical boundary error analysis was used to examine this interface by manipulating listener constraints with a brief familiarization procedure. If familiarization allows listeners to extract relevant segmental and suprasegmental information from dysarthric speech, they should obtain higher intelligibility scores than nonfamiliarized listeners, and their lexical boundary error patterns should approximate those obtained in misperceptions of normal speech. Listeners transcribed phrases produced by speakers with either hypokinetic or ataxic dysarthria after being familiarized with other phrases produced by these speakers. Data were compared to those of nonfamiliarized listeners [Liss et al., J. Acoust. Soc. Am. 107, 3415–3424 (2000)]. The familiarized groups obtained higher intelligibility scores than nonfamiliarized groups, and the effects were greater when the dysarthria type of the familiarization procedure matched the dysarthria type of the transcription task. Remarkably, no differences in lexical boundary error patterns were discovered between the familiarized and nonfamiliarized groups. Transcribers of the ataxic speech appeared to have difficulty distinguishing strong and weak syllables in spite of the familiarization. Results suggest that intelligibility decrements arise from the perceptual challenges posed by the degraded segmental and suprasegmental aspects of the signal, but that this type of familiarization process may differentially facilitate mapping segmental information onto existing phonological categories.

To determine the possibility of new applications of Oriental medicines, we examined the changes in water metabolism of mice that underwent microgravity and were treated with Kampo medicines. Male ICR mice were used in this experiment. Eight extracts of Kampo herbal medicines were dissolved in water and added to the drinking water administered to mice at 1 g/kg body weight for two days. The microgravity experiment was performed at the Japan Microgravity Center. We used a drop-shaft type microgravity experimental system with a free fall of 490 m. Before the drop, 7 ml of physiological saline was injected intraperitoneally. Under fasting and dehydration, body weights were measured and loss of body weight was calculated as urine. Blood samples were collected 24 hours after the microgravity experiment, and the antidiuretic hormone (ADH) in plasma related to water metabolism was measured by the radioimmunoassay (RIA) method. Heat shock protein in the spleen was measured by the enzyme-linked immunosolvent assay (ELISA) method. In the Hachimi-jio-gan and Hochu-ekki-to groups in microgravity, a decrease of urine was observed, which significantly suppressed the increase of ADH due to microgravity. Hachimi-jio-gan reduced the content of heat shock protein (HSP) 70 in the spleen. It is suggested that Hachimi-jio-gan and Hochu-ekki-to could be used as water metabolism adjustment reagents in a space environment. Furthermore, it is suggested that Hachimi-jio-gan could ease the stresses caused by microgravity. The physiological changes resulting from a microgravity environment are serious problems for space flight. Pre-treatment with Kampo medicines is expected to prevent, ease and treat these problems.

Adoptive T cell therapy, involving the ex vivo selection and expansion of antigen-specific T cell clones, provides a means of augmenting antigen-specific immunity without the in vivo constraints that can accompany vaccine-based strategies. A phase I study was performed to evaluate the safety, in vivo persistence, and efficacy of adoptively transferred CD8 + T cell clones targeting the tumor-associated antigens, MART1/MelanA and gp100 for the treatment of patients with metastatic melanoma. Four infusions of autologous T cell clones were administered, the first without IL-2 and subsequent infusions with low-dose IL-2 (at 0.25, 0.50, and 1.0 × 10 6 units/m 2 twice daily for the second, third, and fourth infusions, respectively). Forty-three infusions of MART1/MelanA-specific or gp100-specific CD8 + T cell clones were administered to 10 patients. No serious toxicity was observed. We demonstrate that the adoptively transferred T cell clones persist in vivo in response to low-dose IL-2, preferentially localize to tumor sites and mediate an antigen-specific immune response characterized by the elimination of antigen-positive tumor cells, regression of individual metastases, and minor, mixed or stable responses in 8 of 10 patients with refractory, metastatic disease for up to 21 mo.

Background— Genotype-phenotype correlative studies have implicated 8 particular mutations that cause hypertrophic cardiomyopathy (HCM) as “benign defects,” associated with near-normal survival: N232S, G256E, F513C, V606M, R719Q, and L908V of β-myosin heavy chain ( MYH7 ); S179F of troponin T ( TNNT2 ); and D175N of α-tropomyosin ( TPM1 ). Routine genetic screening of HCM patients for specific mutations is anticipated to provide important diagnostic and prognostic information. The frequency and associated phenotype of these mutations in a large, unselected cohort of HCM is unknown. Methods and Results— A total of 293 unrelated HCM patients were genotyped for the presence of a benign mutation. DNA was obtained after informed consent; specific MHY7, TNNT2 , and TPM1 fragments were amplified by polymerase chain reaction; and the mutations were detected by denaturing high-performance liquid chromatography and automated DNA sequencing. Only 5 (1.7%) of the 293 patients possessed a benign mutation. Moreover, all 5 subjects with an ascribed benign mutation had already manifested clinically severe expression of HCM, with all 5 requiring surgical myectomy, 3 of the 5 having a family history of sudden cardiac death, and 1 adolescent requiring an orthotopic heart transplant. Conclusions— These findings demonstrate the rarity of specific mutations in HCM and challenge the notion of mutation-specific clinical outcomes. Fewer than 2% of the subjects harbored a benign mutation, and those patients with a benign mutation experienced a very serious clinical course.