Chloride ion transport and overexpression of TMEM16A in a guinea-pig asthma model.

BACKGROUND: TMEM16A, a Ca-activated Cl channel, regulates various physiological functions such as mucin secretion. However, the role of TMEM16A in hyper-secretion in asthma is not fully understood. OBJECTIVE: The aim of this study is to evaluate Cl ion transport via TMEM16A and determine the localization of TMEM16A in a guinea-pig asthma model. METHODS: Guinea-pigs were sensitized with ovalbumin (OVA) i.p. on Days 1 and 8. On Day 22, we assessed OVA challenge-induced Cl ion transport in the sensitized tracheas ex vivo in an Ussing chamber, compared with the non-sensitized tracheas. We then examined the effect of T16Ainh-A01, a TMEM16A inhibitor, on the increase in Cl ion transport. The tracheal epithelium was immunostained with an anti-TMEM16A antibody. Epithelial cells from guinea-pig tracheas were cultured at the air-liquid interface in the presence of IL-13 for in vitro study. We studied the effect of TMEM16A inhibitors on Ca-dependent agonist, uridine triphosphate (UTP)-induced increases in Cl ion transport in the cultured cells. The cells were immunostained with an anti-TMEM16A antibody, an anti-MUC5AC antibody and an anti-α-tubulin antibody. RESULTS: OVA challenge induced an increase in short circuit current within 1 min in the OVA-sensitized tracheas but not in the non-sensitized tracheas, which was inhibited by pretreatment of T16Ainh-A01. Sensitized tracheas showed goblet cell metaplasia with more positive TMEM16A immunostaining, particularly in the apical portion compared with the non-sensitized tracheas. The in vitro UTP-induced increase in Cl ion transport was strongly inhibited by pretreatment with T16Ainh-A01, benzbromarone, and niflumic acid. TMEM16A was positively immunostained at the apical portion and in the MUC5AC-positive area in IL-13-induced goblet cell metaplasia. CONCLUSIONS: Antigen challenge and Ca-dependent agonist treatment increased Cl ion transport via the overexpression of TMEM16A in goblet cell metaplasia in a guinea-pig asthma model. TMEM16A inhibitors may be useful for the treatment of hyper-secretion in asthma.

Vessel-Selective 4D-MRA Using Superselective Pseudocontinuous Arterial Spin-Labeling with Keyhole and View-Sharing for Visualizing Intracranial Dural AVFs.

BACKGROUND AND PURPOSE: An accurate assessment of the hemodynamics of an intracranial dural AVF is necessary for treatment planning. We aimed to investigate the utility of 4D-MRA based on superselective pseudocontinuous arterial spin-labeling with CENTRA-keyhole and view-sharing (4D-S-PACK) for the vessel-selective visualization of intracranial dural AVFs. MATERIALS AND METHODS: We retrospectively analyzed the images of 21 patients (12 men and 9 women; mean age, 62.2 [SD,19.2] years) with intracranial dural AVFs, each of whom was imaged with DSA, 4D-S-PACK, and nonselective 4D-MRA based on pseudocontinuous arterial spin-labeling combined with CENTRA-keyhole and view-sharing (4D-PACK). The shunt location, venous drainage patterns, feeding artery identification, and Borden classification were evaluated by 2 observers using both MRA methods on separate occasions. Vessel selectivity was evaluated on 4D-S-PACK. RESULTS: Shunt locations were correctly evaluated in all 21 patients by both observers on both MRA methods. With 4D-S-PACK, observers 1 and 2 detected 76 (80.0%, P < .001) and 73 (76.8%, P < .001) feeding arteries of the 95 feeding arteries identified on DSA but only 39 (41.1%) and 46 (48.4%) feeding arteries with nonselective 4D-PACK, respectively. Both observers correctly identified 10 of the 11 patients with cortical venous reflux confirmed by DSA with both 4D-S-PACK and 4D-PACK (sensitivity = 90.9%, specificity = 90.9% for each method), and they made accurate Borden classifications in 20 of the 21 patients (95.2%) on both MRA methods. Of the 84 vessel territories examined, vessel selectivity was graded 3 or 4 in 73 (91.2%) and 66 (88.0%) territories by observers 1 and 2, respectively. CONCLUSIONS: 4D-S-PACK is useful for the identification of feeding arteries and accurate classifications of intracranial dural AVFs and can be a useful noninvasive clinical tool.

Serum VEGF increases in diabetic polyneuropathy, particularly in the neurologically active symptomatic stage.

AIM: To identify the relationship between vascular endothelial growth factor (VEGF) and diabetic polyneuropathy (DPN). METHODS: Two hundred and twenty diabetic patients participated, 113 with DPN and 107 without DPN. All patients were also classified according to the four stages of DPN (no neuropathy: stage 0; asymptomatic neuropathy: stage 1; symptomatic neuropathy: stage 2; disabling neuropathy: stage 3). Serum VEGF concentration was measured using an enzyme-linked immunosorbent assay (ELISA) and levels between the patients with and without DPN and also between the different stages of DPN, were compared. RESULTS: The mean serum VEGF level in all patients was 264.6 +/- 218.8 pg/ml. The mean serum VEGF level was higher in patients with DPN (310.1 +/- 224.3 pg/ml) than in the patients without DPN (216.5 +/- 204.0 pg/ml, P = 0.0014). Serum VEGF was higher in the 'symptomatic' stage (stage 2, 364.8 +/- 225.9 pg/ml) in comparison with the 'asymptomatic' (stage 1, 256.7 +/- 224.4 pg/ml, P = 0.015) and 'disabling' (stage 3, 180.3 +/- 109.4 pg/ml, P = 0.042) stages. The mean serum VEGF level in patients with diabetic retinopathy (261.1 +/- 210.6 pg/ml) and in patients with diabetic nephropathy (241.5 +/- 185.7 pg/ml) was not increased. CONCLUSIONS: The serum VEGF level is increased in patients with DPN, particularly in patients in the neurologically active 'symptomatic' stage.

Prevalence and incidence rates of chronic inflammatory demyelinating polyneuropathy in the Japanese population.

OBJECTIVE AND METHODS: To characterise the epidemiological features of chronic inflammatory demyelinating polyneuropathy (CIDP) in the Japanese population, this study performed a nationwide assessment of the prevalence and incidence rates in Japan. RESULTS: The prevalence rate per 100 000 was 1.61 in the total population; 2.01 in males and 1.23 in females. The age dependent prevalence rates were 0.23 in juveniles (<15 years old), 1.50 in young adults (15-55 years) and 2.31 in elderly adults (>55 years). The sex and age dependent prevalence rates were 0.22 in males and 0.24 in females in juveniles, 1.81 in males and 1.19 in females in young adults, and 3.12 in males and 1.64 in females in elderly adults. The annual incidence rate per 100 000 was 0.48 in the total population, 0.58 in males and 0.38 in females. The age dependent incidence rate was 0.06 in juveniles, 0.40 in young adults and 0.73 in elderly adults. The sex and age dependent incidence rate was 0.05 in males and 0.08 in females in juveniles, 0.50 in males and 0.30 in females in young adults, and 0.93 in males and 0.58 in females in elderly adults. Both the prevalence and incidence rates were very similar throughout the eight geographical areas studied, from the northern to the southern parts of Japan. CONCLUSIONS: The prevalence and incidence rates were similar to those reported in the Caucasian population. The pathogenic background is suggested to be common throughout the different races and geographic areas, while gender and age effects should be taken into account in the pathogenesis of CIDP.

Autoantibodies against glutamate receptor epsilon2-subunit detected in a subgroup of patients with reversible autoimmune limbic encephalitis.

We investigated the presence of autoantibodies against glutamate receptor (GluR) epsilon2 in serum and cerebrospinal fluid (CSF) samples from 12 consecutive patients with acute encephalitis/encephalopathy by immunoblotting using recombinant GluR epsilon2 as antigen. In 4 patients, IgM autoantibodies against GluR epsilon2 were detected in CSF in the early phase of the disease but were not detectable after several months. Seizures and psychiatric symptoms were noted during the acute phase of the disease in these 4 patients, who showed various degrees of residual amnesia. Immunotherapy was performed on 3 patients (patients 1, 3 and 4), and they showed marked improvements. Immunohistochemistry using these patients' sera showed that immunoreactivity is specifically detected in the cytoplasm of rat hippocampal and cortical neurons. The clinical features and neuroimaging findings of patients with IgM autoantibodies against GluR epsilon2 in CSF resemble those of patients with reversible autoimmune limbic encephalitis.

Crucial role of plasmacytoid dendritic cells in the development of acute colitis through the regulation of intestinal inflammation.

Disruption of intestinal homeostasis can lead to inflammatory bowel diseases endowed susceptibility genes and environmental factors affecting intestinal accumulation and activation of colitogenic phagocytes. Plasmacytoid dendritic cells (pDCs) are immune cells that had been proposed to control innate and adaptive immunity through the massive secretion of type I interferon (IFN-I). However, the contribution of pDCs to the progression of intestinal inflammation remains unclear. Here we show a critical role of pDCs in the initiation of acute colonic inflammation using T-cell-independent acute colitis model with a selective ablation of pDCs. Although pDCs accumulated in the inflamed colon upon mucosal injury, deficiency of pDCs attenuated the development of acute colitis independent of IFN-I signaling, accompanied by the diminished colonic production of proinflammatory cytokines. Furthermore, deficiency of pDCs impaired the mobilization of colitogenic phagocytes into the inflamed colon possibly mediated by the abrogated mucosal production of C-C chemokine receptor 2 ligand. Thus, our findings highlight a critical role of pDCs in the induction of the colonic inflammation that regulates the colonic accumulation of inflammatory phagocytes leading to the initiation and exacerbation of acute colitis, and they may serve a key role in controlling gut mucosal immune homeostasis.

Mechanomyographic determination of post-activation potentiation in myopathies.

OBJECTIVE: There is a need to provide an index of muscle contractility in evaluating myopathies especially in the clinical setting. This study was conducted to investigate if the mechanomyogram post-activation potentiation (MMG-PAP) can be used as an index of muscle contractile force potentiation (force-PAP), if it differs between normal and myopathic muscles, and if it can reflect abnormalities in muscle fiber anatomy. METHODS: The correlation between MMG-PAP and force-PAP was evaluated in 12 normal subjects after maximum voluntary contraction (MVC) of the biceps brachii muscle. The same method was then applied to study MMG-PAP in 16 patients with myopathies, 16 disease and 25 normal controls. Mean fiber diameters and the proportions of type 1 and 2 fibers in biopsied biceps brachii muscle were determined and compared with MMG-PAP values. RESULTS: There was a significant positive correlation between force-PAP (197 +/- 148%) and MMG-PAP (135 +/- 68%) immediately after MVC (P < 0.05). The mean MMG-PAP in myopathies (66 +/- 53%) was significantly lower than those of the disease (128 +/- 34%; P < 0.005) and normal controls (120 +/- 56%; P < 0.005). Patients with non-dystrophic myopathies, including those with myositis, had significantly lower MMG-PAP values (38 +/- 20%; P < 0.005) than those with muscular dystrophy (148 +/- 23%). MMG-PAP did not clearly correlate with either type 2 fiber atrophy or type 2 fiber disproportion based on muscle biopsy analysis of myopathic patients. CONCLUSIONS: This study shows that MMG-PAP can be used as an index of muscle contractility and that it is significantly lower in non-dystrophic myopathies compared to normal subjects. MMG-PAP does not seem to reflect abnormal muscle fiber anatomy. SIGNIFICANCE: MMG-PAP may become a valuable non-invasive tool in augmenting routine clinical electrophysiologic studies especially in evaluating muscle contractility in myopathies.

Studies on the relationship of hepatic anion-binding proteins and sulfobromophthalein-glutathione conjugation in normal and phenobarbital-treated rats.

The enzyme activity which conjugates sulfobromophthalein with glutathione was separated from rat liver supernate by Sephadex G-75 gel filtration, and assayed by two different methods; paper electrophoresis and spectrophotometry. The enzyme activity was found mainly in the second protein fraction, and less than 5% of the activity in the first or third protein fractions. In vitro mixtures of sulfobromophthalein, [3-H]glutathione and rat liver supernate showed that the major part of [3-H]glutathione was detected in the first and second protein fractions, and the remainder in the third protein fraction. Phenobarbital treatment caused an increase of the enzyme activity, sulfobromophthalein and [3-H]glutathione, in the second protein fraction.

Inching method in compression neuropathy of the sural nerve distal to the ankle.

We present the case of a 29-year-old electric engineer with compression neuropathy of the left sural nerve due to occupational boots. Routine nerve conduction study of the sural nerve was normal. However, the sensory nerve action potential was not detected more than 3 cm distal to the lateral malleolus, although it returned to normal values after three years. Inching method of the sural nerve may be necessary for detecting compression sural neuropathy distal to the ankle.

Human T lymphotropic virus-type I Tax induction of CD21/Epstein-Barr virus receptor expression on T cells and its significance in leukemogenesis of adult T cell leukemia.

CD21, which is expressed on B cells, is also expressed on human T lymphotropic virus-type I (HTLV-I)-infected T cell lines. CD21 also serves as a receptor of Epstein-Barr virus (EBV). We evaluated the mechanism of CD21 induction on HTLV-I-infected T cells and its clinical significance in the leukemogenesis of adult T cell leukemia (ATL). CD21 induction was detected at very low levels in T cell lines (Jurkat and CEM cells), and in non- or low-Tax-producing HTLV-I-infected T cell lines (Oh13T, S1T, and Su9T01 cells). In contrast, marked induction of CD21 was detected in high-Tax-producing HTLV-I-infected T cell lines (K3T, F6T, and MT-2). A Jurkat T cell clone stably transfected with tax-expressing cDNA expressed a significant amount of CD21 on the cell surface. These results strongly suggest that HTLV-I Tax induces CD21 on T cells. On two-color analysis, CD21 expression was detected in CD4+ T cells of the primary ATL cells from a subset of patients, suggesting that EBV infection may be associated with the leukemogenesis of ATL, at least in part. However, no genome of EBV was detected in the genomic DNA of six HTLV-I-infected T cell lines or the primary ATL cells separated from all patients, indicating the irrelevance of EBV infection to ATL leukemogenesis.

Vesnarinone exhibits antitumor effect against myeloid leukemia cells via apoptosis.

Vesnarinone is a positive inotropic agent used for treating congestive heart failure. We evaluated its ex vivo effects on myeloid leukemia cell lines and primary acute myelogenous leukemia cells. Vesnarinone inhibited the incorporation of radiolabeled thymidine by a myeloid cell line, HL60, in a dose-dependent manner at concentrations ranging from 0.1 to 30 microg/mL. A maximum 40% suppression was seen at a concentration of 10 microg/mL. Determination of viable cell counts by trypan blue dye exclusion method demonstrated vesnarinone to be cytocidal for HL60 cells. Vesnarinone induced DNA fragmentation as detected by electrophresis in HL60 cells after 72-hour culture; this effect was not inhibited by G-CSF. The apoptosis induced by vesnarinone was also detected by the in situ end-labeling method. Northern blot analysis showed a reduction of c-myc mRNA expression in HL60 cells by vesnarinone. However, immunostaining assay showed no change in the expression of Fas and Bcl-2 proteins. We next examined the effect of vesnarinone on primary myeloid leukemia cells derived from 10 patients: 3 cases of M1, 2 of M2, 3 of M3, 1 of M4, and 1 of M6, by the French-American-British classification. Vesnarinone inhibited the incorporation of thymidine in all cells, with a mean suppression of 58.1%. DNA electrophoresis showed induction of DNA fragmentation in cultured cells with vesnarinone for 72 hours in 8 of the 10 patients with primary leukemia. However, bone marrow mononuclear cells from healthy controls showed no growth suppression or DNA fragmentation in response to vesnarinone. These results suggest that vesnarinone may be useful in treating myeloid leukemia.

NF-kappaB involvement in the activation of primary adult T-cell leukemia cells and its clinical implications.

The HTLV-I provirus-encoded Tax protein induces NF-kappaB in Tax-transfected Jurkat T cells or HTLVL-I- infected T cells in vitro. Tax induction of NF-kappaB is presumed to be involved in proliferation and activation of primary leukemia cells in vivo. Recent studies have demonstrated that NF-kappaB activities in human T cells are mediated by at least four c-Rel-related DNA binding proteins - p50, p55, p75 and p85. We examined the significance of NF-kappaB induction in primary adult T cell leukemia cells and the induction kinetics of each of the four NF-kappaB species. Marked NF-kappaB activity was detected using an electrophoretic mobility shift assay (EMSA) in the primary cells of patients with acute disease, but little activity was noted in the cells of chronic patients. NF-kappaB activity was enhanced in a time-dependent manner in acute type cells cultured with mitogen-free medium; there was no induction of activity in chronic type cells. UV crosslinking demonstrated all four species of NFkappaB complex - high levels of p50 and lower levels of p55 and p75, in acute type cells; chronic type cells showed only the p50. As a control, normal resting T cells similarly showed only p50; control cells showed little change in activity when cultured without mitogenic stimulation, analogous to chronic type ATL. Northern blotting revealed enhancement of c-rel (encoding p85) and KBFI (encoding p50 and p55) expression in acute type cells during culture, while there was no significant enhancement of mRNAs in chronic type ATL cells or unstimulated normal T cells. Northern blotting also revealed that Tax is upregulated at the mRNA level in acute- but not chronic-type cells during culture. Expression of c-rel and KBF1 mRNAs in acute type cells appeared to be related to Tax mRNA expression. These results suggest that Tax is capable of inducing nuclear expression of all four NF-kappaB species in primary ATL cells of acute type patients, with marked effects on p55, p75, and p85. Tax induction of NF-kappaB species is regulated, at least in part, at a pretranslational level involving increases in c-rel and KBF1 mRNA.

Alteration of p16 (CDKN2) gene is associated with interleukin-2-induced tumor cell growth in adult T-cell leukemia.

Because tumorigenesis frequently involves the dysfunction of cell cycle-related proteins, we examined the effect of mutations in CDK inhibitor p16 and its linked genomic loci p15, cl.B, and 1063.7 on the growth of primary adult T-cell leukemia (ATL) cells. Southern blot analysis of primary ATL cells showed a significantly higher incidence of p16 gene alteration in acute ATL than in chronic ATL [67.7% (23/34) vs. 26.1% (6/23), respectively; p<0.003]. Similarly, polymerase chain reaction (PCR) analysis of p16 exon 2 revealed a higher incidence of alteration in acute ATL than in chronic ATL [52.9% (18/34) vs. 26.1% (6/23), respectively; p<0.05]. PCR-single strand conformation polymorphism analysis of exons 1 and 2 of p16 showed no mutations in the patients, with normal pattern by Southern blotting or PCR analysis. Notably five of six chronic ATL patients with abnormal p16 genes progressed to acute crisis within 4 months. PCR analysis of the p16 linked loci 1063.7, p15 exon 2, and cl.B found homozygous deletion in 55.9%, 20.6%, and 2.9% of acute ATL cells and 39.1%, 13.0%, and 0% of chronic ATL cells, respectively, showing no relationship of homozygous deletion in either loci with disease subtypes. In most cases, deletions were seen in multiple genes, including p16. Acute ATL cells had a higher frequency of multigene deletions than chronic ATL cells [44.1% vs. 17.4%; p<0.05]. When leukemic cells were analyzed for interleukin 2 (IL-2) responsive growth, only p16 gene alteration was directly associated with leukemic cell growth activity. Among leukemic cells showing high IL-2 responsiveness, 73.1% (19/26) had p16 gene alteration vs. 27.8% (5/18) of leukemic cells that showed low IL-2 responsiveness (p<0.005). p16 gene alteration was found in 73.3% (14/19) of leukemic cells showing high autonomous growth rates but in only 40.0% (10/25) of those leukemic cells showing low autonomous growth (p<0.03). These results suggest the following: alteration of p16-related genomic regions in ATL is usually a wide rearrangement including the p16 gene; within this region, only p16 gene alteration is associated with disease aggressiveness; and p16 gene deletion may be a proximate event in leukemogenesis.

Positive inotropic effect of insulin-like growth factor-1 on normal and failing cardiac myocytes.

OBJECTIVE: The acute administration of growth hormone (GH) or insulin-like growth factor-1 (IGF-1) improves cardiac performance, possibly contributing to the beneficial effects of GH therapy on heart failure (HF). GH can induce the production of IGF-1 and thus the actions of GH may be mediated through its IGF-1 induction. However, these effects have not yet been demonstrated in failing hearts and the cellular basis of GH or IGF-1-induced inotropic effects remains unknown. We examined the direct effects of GH and IGF-1 on the contractile function and intracellular calcium ([Ca2+]i) homeostasis in normal and failing myocytes. METHODS: To determine whether GH and IGF-1 have a direct effect on myocardial contractility and whether the GH/IGF-1-induced effect was the results of changes in Ca2+ activation, cell shortening and [Ca2+]i transient were simultaneously measured in the left ventricular myocyte preparations, isolated from normal and rapid pacing-induced HF dogs. RESULTS: Basal shortening of HF myocytes was reduced by 64% (p < 0.01). In normal and HF myocytes, GH (0.4-40 x 10(-3) IU/ml) had no effect on either cell shortening or [Ca2+]i transients. In normal myocytes, IGF-1 exerted a positive inotropic effect in a time- and dose-dependent manner (25-500 ng/ml), associated with a parallel increase of [Ca2+]i transient amplitude. IGF-1 increased the shortening magnitude in normal (121 +/- 5% increase from baseline, p < 0.05) and HF (118 +/- 4% increase from baseline, p < 0.05) myocytes. It also increased [Ca2+]i transient amplitude in normal and HF cells by 124 +/- 4 and 125 +/- 7%, respectively. The percent increase of cell shortening and [Ca2+]i transient amplitude was comparable between normal and HF myocytes. Furthermore, IGF-1 did not shift the trajectory of the relaxation phase in the phase-plane plots of cell length vs. [Ca2+]i, indicating that it did not change myofilament Ca2+ sensitivity. CONCLUSIONS: In both normal and HF conditions, IGF-1 exerted an acute direct positive inotropic effect in adult cardiac myocytes by increasing the availability of [Ca2+]i to the myofilaments, possibly explaining the beneficial effect of GH on HF.

Role of Ca2+ availability to myofilaments and their sensitivity to Ca2+ in myocyte contractile dysfunction in heart failure.

OBJECTIVE: Contractile function is depressed at the isolated myocyte level in heart failure (HF), which could result from the decreased availability of intracellular calcium ([Ca2+]i) to the myofibrils and/or the depressed sensitivity of myofilaments to [Ca2+]i. However, the cellular basis of contractile dysfunction remains unestablished. METHODS: We isolated left ventricular myocytes from dogs with rapid pacing-induced HF. Cell shortening and [Ca2+]i transients were measured by indo-1 fluorescence and the myofilament Ca2+ sensitivity was analyzed by the shortening-[Ca2+]i relation in intact myocytes as well as by the pCa tension relation in skinned cells. RESULTS: Peak cell shortening magnitude was depressed in HF, associated with a parallel decrease of [Ca2+]i transient amplitude. There was a significant positive correlation between these two variables (r = 0.71, P < 0.01). In contrast, myofibrillar sensitivity to Ca2+, determined by both intact and skinned myocytes, was comparable between control and HF. Further, there was no significant difference in Ca2+ sensitivity between control and HF even at shorter (1.8 microns) or longer (2.2 microns) sarcomere length. CONCLUSIONS: Using both intact and skinned cellular preparations, a potential defect in myocyte contractile function in HF was a reduction in Ca2+ availability to the myofilaments, rather than the inherent defects in myofilament sensitivity to Ca2+.

Clinical electrophysiologic studies of HTLV-I-associated myelopathy.

Six patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) were studied by electrophysiologic methods. Upper-limb short-latency somatosensory evoked potentials showed slight delay of the N9-N20 interpeak latency in one of 12 limbs, while the lower-limb short-latency somatosensory evoked potentials showed prolonged N20-P40 interpeak latency in eight of 12 limbs. Frequent polyphasic potentials and occasional giant spikes were observed in the distal extremities. F-wave conduction velocity was delayed in some patients. Results of the other nerve conduction studies were unremarkable. Our data provide a valuable extension of the clinical examination of HAM and offer encouragement for a more extensive electrophysiologic study of this entity, especially in the spinal cord.

Electroencephalographic abnormalities in human T-cell lymphotropic virus type I-associated myelopathy.

Thirty-six patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy were studied by electroencephalogram. Twenty-two of 36 patients showed mild to moderate electroencephalographic abnormalities, ranging from poor organization or slowing of the background activity to theta bursts and/or spikes. None of these abnormalities were considered specific for HTLV-I-associated myelopathy. These electroencephalographic abnormalities had no apparent relationship to duration or severity of illness, nor to HTLV-I antibody titers in the cerebrospinal fluid. We document electroencephalographic changes in HTLV-I-associated myelopathy. Our data are consistent with previous reports describing the fact that involvement of regions above the spinal cord may exist in HTLV-I-associated myelopathy.

Werner's syndrome associated with spastic paraparesis and peripheral neuropathy.

A Werner's syndrome patient with spastic paraparesis and polyneuropathy had slowing of central and peripheral nerve conduction. Sural nerve biopsy revealed a significantly higher frequency of demyelination and remyelination and a loss of myelinated fibers. These data suggest that the central and peripheral nervous systems are affected in Werner's syndrome.

Circulating levels of MMP-1, -2, -3, -9, and TIMP-1 are increased in POEMS syndrome.

The authors quantitatively measured levels of matrix metalloproteinases (MMP), tissue inhibitor of metalloproteinases (TIMP), and vascular endothelial growth factor (VEGF) in blood samples of POEMS syndrome. Circulating levels of MMP-1, -2, -3, -9, and TIMP-1 were more increased in patients with POEMS syndrome than in patients with other neurologic disorders or in healthy controls. Serum levels of VEGF and TIMP-1 were strongly correlated with each other. Increased circulating levels of MMP-1, -2, -3, -9, and TIMP-1 may lead to a better understanding the pathogenesis of POEMS syndrome.

Highly accumulated platelet vascular endothelial growth factor in coagulant thrombotic region.

BACKGROUND: Vascular endothelial growth factor (VEGF) is an endothelial cell-specific potent mitogen that induces angiogenesis and microvascular hyperpermeability. Recently, it has been reported that megakaryocytes and platelets contain VEGF in their cytoplasm. OBJECTIVES: To elucidate and confirm the bioactivity and role of VEGF in platelets (platelet VEGF), which may be closely related to vascular thrombosis and atherosclerosis. METHODS: The VEGF localization in megakaryocytes on bone marrow smears was analyzed by immunofluorescence and confocal laser scanning microscopic analysis. The intracellular VEGF expressed in platelets was determined by flow cytometric analysis. Platelet-rich plasma and washed platelets were used to analyze the secretion of VEGF during platelet aggregation by thrombin or gelatinase A (matrix metalloproteinase-2) stimulation. Immunohistochemical studies for VEGF in the thrombotic region were performed. RESULTS AND CONCLUSIONS: Megakaryocytes and platelets are a very rich source of circulating VEGF. Gelatinase A, which is closely associated with vascular remodeling, enhances the VEGF levels released from platelets. VEGF was clearly detected in the fibrin nets of a thrombus. Taken together, platelet VEGF is bioactive as a direct angiogenic growth factor, and may play a very important role in wound healing and atherosclerosis in conjunction with other platelet cytokines such as platelet-derived growth factor, platelet-derived endothelial cell growth factor, transforming growth factor (TGF)-alpha, and TGF-beta.