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81.
Carnitine is a naturally occurring amino acid derivative that is involved in the transport of long-chain fatty acids to the mitochondrial matrix. There, these substrates undergo β-oxidation, producing energy. The major sources of carnitine are dietary intake, although carnitine is also endogenously synthesized in the liver and kidney. However, in patients on dialysis, serum carnitine levels progressively fall due to restricted dietary intake and deprivation of endogenous synthesis in the kidney. Furthermore, serum-free carnitine is removed by hemodialysis treatment because the molecular weight of carnitine is small (161 Da) and its protein binding rates are very low. Therefore, the dialysis procedure is a major cause of carnitine deficiency in patients undergoing hemodialysis. This deficiency may contribute to several clinical disorders in such patients. Symptoms of dialysis-related carnitine deficiency include erythropoiesis-stimulating agent-resistant anemia, myopathy, muscle weakness, and intradialytic muscle cramps and hypotension. However, levocarnitine administration might replenish the free carnitine and help to increase carnitine levels in muscle. This article reviews the previous research into levocarnitine therapy in patients on maintenance dialysis for the treatment of renal anemia, cardiac dysfunction, dyslipidemia, and muscle and dialytic symptoms, and it examines the efficacy of the therapeutic approach and related issues. 相似文献
82.
Hara Masatoshi Tanaka Shigeru Torisu Kumiko Matsukuma Yuta Tsuchimoto Akihiro Tokumoto Masanori Ooboshi Hiroaki Nakano Toshiaki Tsuruya Kazuhiko Kitazono Takanari 《Clinical and experimental nephrology》2021,25(8):822-834
Clinical and Experimental Nephrology - A growing body of evidence has shown that non-alcoholic fatty liver disease (NAFLD) is associated with chronic kidney disease (CKD). Non-invasive fibrosis... 相似文献
83.
Miyake A Akagi T Enose Y Ueno M Kawamura M Horiuchi R Hiraishi K Adachi M Serizawa T Narayan O Akashi M Baba M Hayami M 《Journal of medical virology》2004,73(3):368-377
We have previously reported that concanavalin A-immobilized polystyrene nanospheres (Con A-NS) could efficiently capture HIV-1 particles and that intranasal immunization with inactivated HIV-1-capturing nanospheres (HIV-NS) induced vaginal anti-HIV-1 IgA antibody response in mice. In this study, to evaluate the protective effect of immunization, each three macaques was intranasally immunized with Con A-NS or inactivated simian/human immunodeficiency virus KU-2-capturing nanospheres (SHIV-NS) and then intravaginally challenged with a pathogenic virus, SHIV KU-2. After a series of six immunizations, vaginal anti-HIV-1 gp120 IgA and IgG antibodies were detected in all SHIV-NS-immunized macaques. After intravaginal challenge, one of the three macaques in each of the Con A-NS- and SHIV-NS-immunized groups was infected. Plasma viral RNA load of infected macaque in SHIV-NS-immunized macaques was substantially less than that in unimmunized control macaque and reached below the detectable level. However, it could not be determined whether intranasal immunization with SHIV-NS is effective in giving complete protection against intravaginal challenge. To explore the effect of the SHIV-NS vaccine, the remaining non-infected macaques were rechallenged intravenously with SHIV KU-2. After intravenous challenge, all macaques became infected. However, SHIV-NS-immunized macaques had lower viral RNA loads and higher CD4(+) T cell counts than unimmunized control macaques. Plasma anti-HIV-1 gp120 IgA and IgG antibodies were induced more rapidly in the SHIV-NS-immunized macaques than in the controls. The rapid antibody responses having neutralizing activity might contribute to the clearance of the challenge virus. Thus, SHIV-NS-immunized macaques exhibited partial protection to vaginal and systemic challenges with SHIV KU-2. 相似文献
84.
Hirokazu Tsukahara Masahiro Hiraoka Masanori Kurivama Masakazu Saito Kiyoshi Morikawa Mitsuhiko Kuroda Toshiro Tominaga Masakatsu Sudo 《Pediatric nephrology (Berlin, Germany)》1993,7(2):199-201
Urinary 1-microglobulin (U-A1M) was measured in healthy term infants on days 1, 4, 7, 14, 28, 90 and 180 of life. U-A1M was high until day 14 and declined thereafter. It was significantly correlated with urinary 2-microglobulin (U-B2M) throughout the study, but not with serum A1M on days 1 or 7. Similar to U-B2M, U-A1M in the clinically stable term infants with intrauterine growth retardation (n=4–7) was not elevated on days 1–7. In the sick infants who needed immediate resuscitatio at birth (n=4–8), U-A1M as well as U-B2M was high on days 1–7 and then decreased to normal levels, suggesting that U-A1M can be used as a sensitive marker of acute proximal tubular damage and its recovery. These observations indicate that U-A1M is a useful index of proximal tubular function in early infancy. 相似文献
85.
Marked Suppression of T Cells by a Benzothiophene
Derivative in Patients with Human T-Lymphotropic Virus Type
I-Associated Myelopathy/Tropical Spastic Paraparesis
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Masahiko Makino Miyuki Azuma Shin-Ichi Wakamatsu Yukio Suruga Shuji Izumo Mitchel M. Yokoyama Masanori Baba 《Clinical and Vaccine Immunology : CVI》1999,6(3):316-322
In a search for new anti-autoimmune agents that selectively
suppress activation of autoreactive T cells, one such agent,
5-methyl-3-(1-methylethoxy)benzo[b]thiophene-2-carboxamide
(CI-959-A), was found to be effective. This compound, which is known to
suppress tumor necrosis factor alpha (TNF-α)-induced CD54 expression,
inhibited the primary proliferative response of the T cell to antigen
(Ag)-presenting cells (APCs) including allogenic dendritic cells (DCs),
autologous Epstein-Barr virus-infected B cells, and human T
lymphotropic virus type I (HTLV-I)-infected T cells. Autoreactive T
cells from patients with HTLV-I-associated myelopathy/tropical spastic
paraparesis (HAM/TSP) spontaneously proliferate in vitro, and their
activation is reported to be associated with CD54 expression. The
spontaneous proliferation of T cells from patients with HAM/TSP was
entirely blocked by CI-959-A. However, in this study, the T-cell
proliferation in 15 patients with HAM/TSP was found to depend more
extensively on major histocompatibility complex (MHC) class II and CD86
than on CD54 Ags. Since most important APCs for the development of
HAM/TSP are DCs and HTLV-I-infected T cells, the effect of CI-959-A on
DC generation and on the expression of surface molecules on activated T
cells is examined. CI-959-A suppressed recombinant
granulocyte-macrophage colony stimulating factor (GM-CSF)- and
recombinant interleukin-4-dependent differentiation of DCs from
monocytes and inhibited the expression of CD54 and, more extensively,
MHC class II and CD86 Ags. CI-959-A showed little toxicity toward
lymphoma or HTLV-I-infected T-cell lines or toward monocytes and
cultured DCs. These results suggest that CI-959-A might be a potent
anti-HAM/TSP agent.Human T lymphotropic virus type I
(HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP)
is thought to be an autoimmune disease induced by HTLV-I infection
(8, 9, 24). The T lymphocytes obtained from patients with
HAM/TSP patients produce interleukin-2 (IL-2) in vivo and proliferate
spontaneously in vitro without any additional stimuli or cytokines
(35). This spontaneous proliferation of T lymphocytes (SPL)
depends on the interaction of T cells with antigen (Ag)-presenting
cells (APCs) such as dendritic cells (DCs) (17, 25) and
HTLV-I-infected CD4+ T cells (15, 32). The DCs
localized in the blood and nonlymphoid organs are considered to be
functionally immature, in that they are optimized for the uptake and
processing of Ag but not for the initiation of primary T-cell
responses. However, after the uptake of Ag and exposure to inflammatory
agents including tumor necrosis factor alpha (TNF-α) and IL-1, the
DCs undergo a process of maturation and gain the ability to present Ag
to T cells for their priming (22, 26). In addition to DCs,
HTLV-I-infected CD4+ T cells directly stimulate autologous
CD4+ T cells in a major histocompatibility complex (MHC)
class II- and CD86 molecule-dependent fashion (32). Among
the T cells stimulated with these APCs, some might cross-react with
self Ags and closely associate with the development of HAM/TSP.We have been searching for compounds that inhibit the cellular
interaction between APCs and T cells to suppress the activation of
autoreactive and Ag-specific T cells. The molecules associated with the
APC-T cell interaction may provide an effective target for therapy for
autoimmune diseases. Binding of APCs and T cells is initiated by
contact of adhesion molecules, such as CD54 and CD11a/CD18, expressed
on both cells, and induction of sustained proliferation of T cells
requires two independent signals provided by APCs: a T-cell
receptor-mediated Ag-specific signal and a signal mediated by
costimulatory molecules (CSMs) (10, 20) including CD86 and
CD58 Ags (1, 11, 31). Blocking of their tight binding
through adhesion molecules or interaction of the CSMs with CSM ligands
effectively suppressed the abnormal expansion of disease-associated T
cells in vivo and in vitro (19, 30, 32) and sometimes
effectively induced a long-term unresponsiveness of T cells to recall
stimuli.5-Methyl-3-(1-methylethoxy)benzo[b]thiophene-2-carbox-amide
(CI-959-A) is known to inhibit CD54 expression, and its derivative is
reported to inhibit casein kinase II (4). In the present
study, we found that CI-959-A markedly suppressed SPL in patients with
HAM/TSP. Furthermore, the compound suppressed the primary T-cell
proliferative response to stimuli provided by various APCs, the
differentiation of immature DCs from monocytes and their subsequent
maturation, and the induction of expression of MHC class II, CD54, and
CD86 Ags on activated CD4+ T cells. 相似文献
86.
Sato T Sakurada S Takahashi N Sakurada T Tan-No K Wako K Kisara K 《European journal of pharmacology》1999,369(2):183-187
To determine the role of mu-opioid receptor subtypes, mu1 and mu2, in antinociception induced by intrathecal (i.t.) or intracerebroventricular (i.c.v.) injection of morphine, we assessed the effect of naloxonazine, a selective antagonist at mu1-opioid receptors. The antinociceptive effects of morphine were measured using four different nociceptive tests. The selective mu1 antagonist, naloxonazine (35 mg/kg, s.c.), 24 h before testing antagonized the antinociceptive effect of morphine on responses to chemical and thermal stimuli to a greater extent than that on responses to mechanical stimuli, as judged from ED50 values. The present results suggest that the antinociceptive activity of both i.t. and i.c.v. morphine on responses to chemical and thermal stimuli may be mediated through the mu1-opioid receptor subtype (naloxonazine-sensitive sites). These findings may be interpreted as indicative of the existence of mu1-receptor subtypes capable of mediating antinociception not only in supraspinal sites but also in spinal sites. 相似文献
87.
Local blood flow of the bowel wall was measured by hydrogen clearance method both in the muscular and submucosal layers in the mongrel dog, separately and concurrently. A platinum wire electrode with a bare tip of 0.5 mm in length and 0.2 mm in diameter was inserted into each layer. About 10 per cent hydrogen gas was inhalated directly through the side hole attached to the endotracheal tube for 1–2 minutes and the obtained clearance curves were plotted on the semi-logarithmic scale, which was almost monoexponential. The results obtained were as follows:
- Mean basal perfusion rate of the muscular layer of the intestine was 0.81–0.92 ml/min/gm, whereas that of the submucosal layer was 1.29–1.31 ml/min/gm, respectively. There was little difference of perfusion rates between the small and the large intestine. The results showed good correlationship with those reported by other authors.
- The effect of vasoactive substances such as vasoconstrictor and vasodilator on the local blood flow in the bowel wall was confirmed.
- This method is repeatedly applicable for measurement and also renders the information on the distribution of blood flow in the splanchnic area.
88.
The human T-cell factor-4 gene splicing isoforms, Wnt signal pathway, and apoptosis in renal cell carcinoma. 总被引:4,自引:0,他引:4
89.
Satoshi Katsuno Tetsuya Ishiyama Masanori Sakaguchi Hiroki Takemae 《The Laryngoscope》1997,107(5):661-664
Patients with advanced cervical cancers often have direct invasion of their carotid arteries. The prognosis for these patients with nonsurgical therapy is extremely poor. Because complete tumor removal is the only therapy that can offer these patients a chance for cure, carotid resection should be performed. We performed carotid resection and reconstruction on nine patients with advanced cervical cancers. Of these patients, none suffered from severe neurologic postoperative complications such as permanent hemiplegia. Three of the nine patients have been disease free for more than 24 months. These three patients would not have survived without carotid resection. Further study will show the usefulness of carotid resection and reconstruction in decreasing the morbidity and mortality in patients with cervical cancer involving the carotid artery. 相似文献
90.
Testicular primary non-Hodgkin's lymphoma (NHL) is said to account for about 5% of all testicular tumors and about 2% of extranodular lymphoma. From a clinical standpoint, we reviewed testicular NHL of stage IE treated at our department over the past 18 years. Among the 865 cases of NHL, 19 (2.2%) were primary testicular NHL, stage IE. The 19 patients had a median age of 62 years (range 48-77 years), all had diffuse B-cell lymphoma. Of the 19 patients, 8 were treated with radiotherapy after high inguinal orchiectomy (Group I), 4 received both postoperative radiotherapy and chemotherapy (Group II), and 7 received additional prophylactic intrathecal chemotherapy (Group III). The 5-year survival rates for Groups I, II and III were 37.5%, 50%, and 100%, respectively. None of the patients receiving prophylactic intrathecal chemotherapy had relapse in the central nervous system and all of them are alive and disease-free. Primary testicular NHL is relatively common among elderly persons, and many patients die as a result of central nervous system recurrence. These results suggest that preventive measures for central nervous system recurrence such as intrathecal injection of anticancer agents should be taken into consideration as early as at the induction of remission. 相似文献