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11.
Epstein-Barr virus (EBV) exhibits tropism for both lymphocytes and epithelial cells and can induce both replicative (productive/lytic) and latent (persistent) infections that result in a variety of human diseases. With regard to lymphocytes, latent EBV infection is linked to development of heterogeneous lymphoproliferative disease (LPD), such as B-cell LPD and T-cell/natural killer cell (T/NK cell) LPD. Unlike B-cell LPD, LPD derived from T-cells and NK cells sometimes has overlapping clinical symptoms, as well as histologic and immunophenotypic features, because both types of cells are derived from a common precursor. However, determination of cell lineage is important in classification of lymphoid neoplasms, and combined modern techniques allows us to distinguish NK cell LPD from T-cell LPD in most instances. Because NK cell LPD seems to be heterogeneous in terms of clinical features, prognosis, and diagnosis and has a monoclonal or polyclonal (or oligoclonal) nature, this review attempts to clarify recent research and clinical findings and to establish diagnostic and therapeutic strategies.  相似文献   
12.
STUDY OBJECTIVE: To test the hypothesis that haplotypes of the interleukin (IL)-10 gene are associated with clinical outcomes, comparing critically ill patients with sepsis from pneumonia vs those with extrapulmonary sepsis. DESIGN: Genetic association study. SETTING: Medical/surgical ICUs in a tertiary-care, university-affiliated teaching hospital. PATIENTS: Of 550 white patients with sepsis, 158 had pneumonia as the principle cause of their sepsis and 392 had an extrapulmonary source of sepsis. MEASUREMENTS: Haplotypes of the IL-10 gene were defined by measurement of haplotype tag single-nucleotide polymorphisms (SNPs). Primary outcome was 28-day survival. Secondary outcomes were days alive and free of organ dysfunction. RESULTS: Three SNPs in the IL-10 gene (-592 C/A, +734 G/T, and +3367 G/A) identified four major haplotypes: CGG, AGG, CTA, and CTG. Patients with pneumonia who carried one or two copies of the CGG haplotype had greater 28-day mortality (51.4%) than patients who did not carry this haplotype (29.1%, p = 0.007). Carriers of CGG had significantly more cardiovascular dysfunction (and use of vasopressors), renal dysfunction (and requirement of dialysis), hepatic dysfunction, and hematologic dysfunction (p < 0.05 in each case). In contrast, in patients with an extrapulmonary source of infection there was no significant association of the CGG haplotype (or any measured IL-10 genotype) with 28-day mortality or organ dysfunction. CONCLUSIONS: The IL-10 haplotype - 592C/734G/3367G is associated with increased mortality and organ dysfunction in critically ill patients with pulmonary sepsis but not in similarly ill patients with extrapulmonary sepsis. Therefore, polymorphisms within the IL-10 gene may be predictors of outcome in patients with sepsis from pneumonia.  相似文献   
13.
14.
OBJECTIVES: Fabry disease is caused by deficiency of alpha-galactosidase A, and typically causes multi-organ dysfunction. Patients with manifestations limited to the heart, mainly left ventricular hypertrophy (LVH), have been reported as a disease variation. We have reported a 3% prevalence of this cardiac variant in men with LVH, which we designated 'cardiac Fabry disease'. The purposes of this study were to evaluate the terminal stage cardiac manifestations and autopsy findings in patients with cardiac Fabry disease. METHODS: We examined seven terminal stage patients with cardiac Fabry disease. During hospitalization, standard 12-lead electrocardiograms, Holter electrocardiograms, and echocardiograms were obtained. Autopsies were performed and macroscopic along with microscopic findings were evaluated. RESULTS: Six patients died of heart failure and one of ventricular fibrillation. Electrocardiograms revealed the presence of conduction abnormalities and nonsustained ventricular tachycardia. Echocardiograms and autopsy findings revealed LVH in all patients. Localized basal posterior wall thinning of the left ventricle was detected in the six patients who died of heart failure. All patients had severe left ventricular dysfunction. Histologically, myocardial cells, but not cardiac vascular endothelial cells, showed glycosphingolipid accumulation. No accumulation was observed in other organs or in systemic vascular endothelial cells. CONCLUSIONS: Severe left ventricular dysfunction with associated conduction disturbances and ventricular arrhythmias occur in patients with terminal stage cardiac Fabry disease. Furthermore, LVH is present and associated with thinning of the base of the left ventricular posterior wall. In contrast to typical Fabry disease, accumulation of glycosphingolipids was observed in myocardial cells but not in other organs.  相似文献   
15.
We studied cross-reactive antibodies against avian influenza H5N1 and 2009 pandemic (p) H1N1 in 200 serum samples from US military personnel collected before the H1N1 pandemic. Assays used to measure antibodies against viral proteins involved in protection included a hemagglutination inhibition (HI) assay and a neuraminidase inhibition (NI) assay. Viral neutralization by antibodies against avian influenza H5N1 and 2009 pH1N1 was assessed by influenza (H5) pseudotyped lentiviral particle-based and H1N1 microneutralization assays. Some US military personnel had cross-neutralizing antibodies against H5N1 (14%) and 2009 pH1N1 (16.5%). The odds of having cross-neutralizing antibodies against 2009 pH1N1 were 4.4 times higher in subjects receiving more than five inactivated whole influenza virus vaccinations than those subjects with no record of vaccination. Although unclear if the result of prior vaccination or disease exposure, these pre-existing antibodies may prevent or reduce disease severity.Outbreaks of 1997 avian influenza H5N1 and 2009 pandemic (p) H1N1 in humans have provided an opportunity to gain insight into cross-reactive immunity. The US military periodically collects and stores serum samples from service members linked to medical records.1 We measured cross-reactive antibodies in stored serum to avian influenza H5N1 and 2009 pH1N1 from US military personnel and identified factors associated with presence of neutralizing antibodies.Two hundred archived serum samples were obtained from the US Department of Defense Serum Repository. They were representative of a wide cross-section of active military personnel at the times of collection, whereas specific geographic information was not available on the individual selected; the cohort represents the general US military population, which is deployed throughout the United States and globally. Fifty samples each were selected from four birth cohorts: (1) < 1949, (2) 1960–1965, (3) 1966–1971, and (4) 1972–1977. Within each cohort, 25 samples were collected in the year 2000 (before the introduction of intranasal live attenuated influenza vaccine [LAIV]), and 25 samples were collected in 2008 (where 51% of donors had received LAIV). It has been suggested that LAIV elicits cross-reactive immunity.2,3 The samples were all collected before the outbreak of 2009 pH1N1, and there have not been any reported outbreaks of H5N1 in US military personnel.Assays used to measure antibodies included a hemagglutination inhibition (HI) assay and a neuraminidase inhibition (NI) assay.4 Viral neutralization by antibodies against H5N1 and 2009 pH1N1 was assessed by influenza (H5) pseudotyped lentiviral particle-based (H5pp)5 and microneutralization assays, respectively. Electronic medical and vaccination records from the Defense Medical Surveillance System (DMSS), which captured records before the serum sample date, were linked to samples and compared with the in vitro results.1The odds ratios (ORs) and 95% confidence intervals (95% CIs) of univariate and multivariate binary logistic regression analyses were used to determine the association between donor characteristics and positive antibody responses. A multiple logistic regression model was constructed, and it included independent variables with a P value of < 0.05 in univariate logistic regression. A P value of < 0.05 was considered to indicate statistical significance. SPSS 12.0 for Windows (SPSS Inc., Chicago, IL) was used to perform all statistical analysis.Cross-reactivity is summarized in 5 and 22.5% for the NI assay. H5pp and NI antibody titers to H5N1 were evenly distributed among birth cohorts and did not differ substantially based on history of vaccination or prior respiratory infections. Of those individuals with neutralizing antibodies to H5N1 (N = 28), 32.1% also had neutralizing antibodies to pH1N1, whereas 19.3% of those individuals with any H5N1-specific antibody response also had neutralizing antibodies to pH1N1 (
Characteristics (n)H5N12009 pH1N1§
HI assay* % positive (GM titer)H5pp % positive (GM titer)NI assay % positive (GM titer)HI assay % positive (GM titer)Neutralization % positive (GM titer)NI assay % positive (GM titer)
Total
 2000.5 (5.1)14.0 (21.4)22.5 (121.6)5.5 (7.1)16.5 (20.4)9.0 (92.8)
Birth cohort
 1936–1949 (50)2.0 (5.3)18.0 (22.0)24.0 (126.0)6.0 (7.3)16.0 (19.5)12.0 (97.6)
 1960–1965 (50)0.0 (5.0)16.0 (20.3)26.0 (129.6)6.0 (7.7)30.0 (27.5)6.0 (90.3)
 1966–1971 (50)0.0 (5.0)12.0 (23.3)20.0 (117.9)10.0 (8.0)16.0 (23.6)10.0 (92.2)
 1972–1977 (50)0.0 (5.3)10.0 (20.0)20.0 (113.7)0.0 (5.7)4.0 (13.6)8.0 (91.5)
Serum collection year
 Y2000 (100)0.0 (5.1)15.0 (21.7)21.0 (120.3)7.0 (7.3)16.0 (20.6)11.0 (94.5)
 Y2008 (100)1.0 (5.2)13.0 (21.1)24.0 (123.0)4.0 (7.0)17.0 (20.1)7.0 (91.2)
Sex
 Female (32)3.1 (5.7)21.9 (26.3)12.5 (102.4)3.1 (6.9)12.5 (19.2)6.3 (96.7)
 Male (168)0.0 (5.0)12.5 (20.5)24.4 (125.7)6.0 (7.2)17.3 (20.6)9.5 (92.1)
Any cross-reactive antibody to
 H5N1 (57)8.8 (8.9)19.3 (25.2)22.8 (119.9)
 pH1N1 (45)2.2 (5.3)28.9 (31.2)37.8 (165.2)
Neutralizing antibodies to
 H5N1 H5pp (28)10.7 (9.5)32.1 (33.6)25.0 (116.9)
 2009 pH1N1 neutralization (33)3.0 (5.4)27.3 (28.9)30.3 (140.3)
Lifetime seasonal vaccinations
 No record (66)0.0 (5.1)10.6 (20.2)27.7 (128.1)7.6 (7.4)15.2 (20.6)12.1 (96.5)
 1–5 vaccinations (88)1.1 (5.2)15.9 (21.5)17.0 (109.2)5.7 (7.1)17.0 (20.5)6.8 (89.1)
  > 5 vaccinations (46)0.0 (5.1)15.2 (22.2)32.6 (138.8)2.2 (6.8)17.4 (19.7)8.7 (95.0)
Time since last vaccine
 No record (66)0.0 (5.1)10.6 (20.2)22.7 (128.1)7.6 (7.4)15.2 (20.6)12.1 (96.5)
  ≤ 1 year (96)0.0 (5.1)15.6 (21.5)24.0 (120.7)4.2 (7.1)19.8 (21.0)8.3 (91.2)
 > 1 year (38)2.6 (5.3)15.8 (22.4)18.4 (113.4)5.2 (6.8)10.5 (18.3)5.3 (90.6)
Vaccination history lifetime (at least one dose)
 No record of vaccination (66)0.0 (5.1)10.6 (20.2)22.7 (128.1)7.6 (7.4)15.2 (20.6)12.1 (96.5)
 Inactivated whole virus (71)0.0 (5.0)14.1 (20.4)22.5 (115.7)2.8 (6.4)15.5 (19.6)5.6 (87.1)
 Split type (102)1.0 (5.0)15.7 (20.4)21.6 (115.7)4.9 (6.4)19.6 (19.6)6.9 (87.1)
 Influenza vaccine not otherwise specified (16)0.0 (5.2)12.5 (27.9)37.5 (166.4)0.0 (6.2)6.3 (16.1)12.5 (102.3)
 Live attenuated intranasal (50)0.0 (5.1)10.0 (18.8)20.0 (112.2)4.0 (7.0)18.0 (20.3)4.0 (85.2)
History of respiratory illness
 No record of illness (119)0.0 (5.0)10.1 (18.5)18.5 (112.6)4.2 (7.0)15.1 (20.5)8.4 (90.7)
 Influenza-like illness (4)0.0 (5.0)25.0 (20.7)0.0 (80.0)0.0 (8.4)25.0 (28.3)25.0 (100.2)
 Upper respiratory infection (65)1.5 (5.4)23.1 (29.3)27.7 (135.0)7.7 (7.3)18.5 (20.7)9.2 (93.1)
 Lower respiratory infection (37)2.7 (5.6)18.9 (30.2)35.1 (157.6)8.1 (8.1)21.6 (22.4)13.5 (108.4)
 Respiratory illness past year (28)0 (5.1)25.0 (25.1)32.1 (154.9)7.1 (8.0)28.6 (24.4)3.6 (86.3)
Open in a separate windowTiters with a value of zero (below the detection limit) were assigned a value of five for calculation of geometric means (GMs).*H5N1, A/Vietnam/1203/2004; positive titer ≥ 40.H5 hemagglutinin (A/Cambodia/408008/05) pseudotyped lentiviral particle; positive titer ≥ 160.Reassortant H1N1 (HA, PB1, PB2, PA, NP, and M from H1N1 [A/PR/8/34]; N1 from H5N1 [A/Vietnam/DT-036/2005]); positive titer ≥ 160.§2009 H1N1, A/California/04/2009; same positive titer cutoffs as for H5N1.As with H5N1, samples with positive HI titers were low for 2009 pH1N1 at 5.5%, whereas neutralizing antibody titers were higher, with 16.5% positive in the microneutralization assay but only 9% positive in the NI assay. Positive neutralization titers were less evenly distributed among birth cohorts, with only 4% positive in the 1972–1977 birth cohort, whereas 30% were positive in the 1960–1965 cohort. Like H5N1, positive antibody titers to 2009 pH1N1 did not differ substantially based on history of vaccination or prior respiratory infections. Of those individuals with neutralizing antibodies to pH1N1 (N = 33), 27.3% also had neutralizing antibodies to H5N1, whereas 28.9% of those individuals with any pH1N1-specific antibody response also had neutralizing antibodies to H5N1.Univariate associations between the prevalence of cross-reactive antibodies to H5N1 and 2009 pH1N1 and independent variables, including year of birth, serum collection year, sex, and seasonal influenza vaccination history, are shown in Characteristic (n)2009 pH1N1H5N1PrevalenceOR (95% CI)Adjusted OR (95% CI)PrevalenceOR (95% CI)Positive neutralizing antibody33 (16.5%)28 (14.0%)Serum collection year 2000 (100)16 (16.0%)ReferenceReference15 (15.0%)Reference 2008 (100)17 (17.0%)1.1 (0.5–2.3)0.7 (0.3–1.8)13 (13.0%)0.9 (0.4–1.9)Birth cohort 1936–1949 (50)8 (16.0%)4.6 (0.9–22.7)5.3 (1.0–27.0)9 (18.0%)2.0 (0.6–6.4) 1960–1965 (50)15 (30.0%)10.3 (2.2–47.9)11.0 (2.3–52.9)8 (16.0%)1.7 (0.5–5.7) 1966–1971 (50)8 (16.0%)4.6 (0.9–22.7)5.1 (1.0–26.2)6 (12.0%)1.2 (0.4–4.3) 1972–1977 (50)2 (4.0%)ReferenceReference5 (10.0%)ReferenceSex Female (32)4 (12.5%)Reference7 (21.9%)Reference Male (168)29 (17.3%)1.5 (0.5–4.5)21 (12.5%)0.5 (0.2–1.3)Positive neutralizing antibody titers H5pp (57)11 (19.3%)1.3 (0.6–2.9) pH1N1 (45)13 (28.9%)3.8 (1.6–8.7)Vaccination record Number of seasonal influenza vaccinations  No record (66)10 (15.2%)Reference7 (10.6%)Reference  1–5 vaccinations (88)15 (17.0%)1.2 (0.5–2.8)14 (15.9%)1.6 (0.6–4.2)  > 5 vaccinations (46)8 (17.4%)1.2 (0.4–3.3)7 (15.2%)1.5 (0.5–4.7) Time since last vaccination  No record (66)10 (15.2%)Reference7 (10.61%)Reference   ≤ 1 year (96)19 (19.8%)1.4 (0.6–3.2)15 (15.6%)1.6 (0.6–4.1)  > 1 year (33)4 (10.5%)0.7 (0.2–2.3)6 (15.8%)1.6 (0.5–5.1) Number of inactivated whole virus vaccinations  No record (129)22 (17.1%)ReferenceReference18 (14.0%)Reference  1–5 vaccinations (53)4 (7.5%)0.4 (0.1–1.2)0.4 (0.1–1.4)7 (13.2%)0.9 (0.4–2.4)  > 5 vaccinations (18)7 (38.9%)3.1 (1.1–8.9)4.4 (1.3–15.6)3 (16.7%)1.2 (0.3–4.7) Time since last inactivated whole virus vaccination  No record (129)22 (17.1%)Reference18 (14.0%)Reference   ≤ 1 year (19)4 (21.1%)1.3 (0.4–4.3)3 (15.8%)1.2 (0.3–4.4)  > 1 year (52)7 (13.5%)0.8 (0.3–1.9)7 (13.5%)1.0 (0.4–2.5) Number of split type vaccinations  No record (98)13 (13.3%)Reference12 (12.2%)Reference  1–5 vaccinations (94)19 (20.2%)1.7 (0.8–3.6)14 (14.9%)1.3 (0.6–2.9)  > 5 vaccinations (8)1 (12.5%)0.9 (0.1–8.2)2 (25.0%)2.4 (0.4–13.2) Time since last split type vaccination  No record (98)13 (13.3%)Reference12 (12.2%)Reference   ≤ 1 year (44)10 (22.7%)1.9 (0.8–4.8)10 (22.7%)2.1 (0.8–5.3)  > 1 year (58)10 (17.2%)1.4 (0.6–3.3)6 (10.3%)0.8 (0.3–2.3) Number of intranasal LAIV vaccinations  No record (150)24 (16.0%)Reference23 (15.3%)Reference  1–5 vaccinations (50)9 (18.0%)1.2 (0.5–2.7)5 (10%)0.6 (0.2–1.7) Time since last intranasal LAIV vaccination  No record (150)24 (16.0%)Reference23 (15.3%)Reference   ≤ 1 year (34)7 (20.6%)1.4 (0.5–3.5)3 (8.8%)0.5 (0.2–1.9)  > 1 year (16)2 (12.5%)0.8 (0.2–3.5)2 (12.5%)0.8 (0.2–3.7)Open in a separate windowTo the best of our knowledge, the present study is the first report of cross-reactive antibodies to both H5N1 and 2009 pH1N1 in a US military population. Cross-reactive antibodies to both influenza viruses were common in this population. Most serum samples (86%) positive in the H5N1 neutralization assay had no detectable HI activity (titer ≥ 10), whereas 94% of samples that neutralized 2009 pH1N1 also had detectable HI activity (titer ≥ 10; data not shown). In addition, cross-reactive antibodies to avian influenza H5N1 were not necessarily accompanied by cross-reactive antibodies to 2009 pH1N1. Taken together, these findings suggest that the observed cross-reactive neutralization against the two influenza viruses was caused by different antibodies in serum samples.This report is also the first report to associate history of receiving more than five doses of inactivated whole influenza virus vaccine with neutralizing antibodies against 2009 pH1N1. This finding suggests a protective advantage of repeated vaccination with seasonal whole virus vaccine, generating cross-reactive antibodies against previously unencountered strains. It has been suggested that the high immunogenicity of the inactivated whole virus vaccine is partly caused by the adjuvant effect of the viral RNA presented, stimulating innate immunity through the Toll-like receptor (TLR) 7-dependent pathway.6 We hypothesize that the combined effect of adjuvant activity and the heterogenous mix of flu strains that an individual would be exposed to over the course of multiple seasonal vaccinations may enhance the breadth of antibody response and promote the generation of cross-reactive antibodies.A retrospective case-control study conducted in US military personnel after the outbreak of 2009 pH1N1 showed that both 2008–2009 seasonal influenza vaccine and history of seasonal vaccine in the prior 4 years afforded some protection against pH1N1. Vaccine effectiveness (VE) was high in persons ≥ 40 (55%) or < 25 (50%) years of age but very low in persons 25–39 years of age (< 10%).7 These findings correlate with the high levels of cross-reactive 2009 pH1N1 antibodies reported here, with 30% in the 1960–1965 cohort (age range = 35–48) but only 4% in the 1972–1977 cohort (age range = 23–36). Our findings are similar to the results found recently in an elderly population in the United States.8 The exception is in those individuals born before 1950, in whom antibody responses were much higher in this cohort. Both our study and the US study differ from two recent seroprevalence studies in Singapore and China, where cross-reactive antibodies were rare in various age groups.9,10 High seasonal influenza vaccination rates in US military personnel found here and prior studies11 may explain the differences observed in these populations, although results from small retrospective seroprevalence studies should be interpreted cautiously. Possible alternative explanations include differences in laboratory assay methods, natural influenza exposure in the sampled populations, and/or use of convenience sampling methods.Studies in humans suggest that the antibody to influenza neuraminidase is associated with resistance to influenza.12 A recent serological study in a small number of human serum samples showed that 24% had cross-reactive antibodies to avian N1,13 similar to our findings (22.5%). In addition, we observed that 9% of serum samples had cross-reactive antibodies to pH1N1.Like pH1N1, persons < 40 years old seem to be most affected by H5N1 infection, with infection rarer in older individuals.14 However, we did not find a difference in cross-reactive antibody prevalence to either neuraminidase or neutralizing antibodies (H5pp) with year of birth or other immunologic markers of exposure, including vaccination history or prior respiratory illness.A possible limitation of our study is that the DMSS may not have captured all relevant medical encounter and/or vaccination data, particularly for encounters that were not entered into the system electronically or coded accurately. Data in the DMSS are provider-dependent, and the DMSS captures data from various historical time periods, dating back to 1980 for immunization data, 1985 for Department of Defense Serum Repository specimens, 1990 for demographic data, and only 1996 for outpatient data. Interpretation of data presented on history of respiratory illness, which is entirely dependent on voluntary provider reporting and International Classification of Diseases (ICD-9) coding, is particularly limited by lack of virologic confirmation.Cross-reactive immunity to pathogenic influenza strains was found in a subset of US military service members, and it may serve to prevent or reduce the severity of influenza. A better understanding of the mechanisms underlying the development of cross-reactive antibodies will aid in the development of more effective preventive and therapeutic measures.  相似文献   
16.
Protein aggregation can inhibit clathrin-mediated endocytosis by chaperone competition     
Anan Yu  Yoko Shibata  Bijal Shah  Barbara Calamini  Donald C. Lo  Richard I. Morimoto 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(15):E1481-E1490
Protein conformational diseases exhibit complex pathologies linked to numerous molecular defects. Aggregation of a disease-associated protein causes the misfolding and aggregation of other proteins, but how this interferes with diverse cellular pathways is unclear. Here, we show that aggregation of neurodegenerative disease-related proteins (polyglutamine, huntingtin, ataxin-1, and superoxide dismutase-1) inhibits clathrin-mediated endocytosis (CME) in mammalian cells by aggregate-driven sequestration of the major molecular chaperone heat shock cognate protein 70 (HSC70), which is required to drive multiple steps of CME. CME suppression was also phenocopied by HSC70 RNAi depletion and could be restored by conditionally increasing HSC70 abundance. Aggregation caused dysregulated AMPA receptor internalization and also inhibited CME in primary neurons expressing mutant huntingtin, showing direct relevance of our findings to the pathology in neurodegenerative diseases. We propose that aggregate-associated chaperone competition leads to both gain-of-function and loss-of-function phenotypes as chaperones become functionally depleted from multiple clients, leading to the decline of multiple cellular processes. The inherent properties of chaperones place them at risk, contributing to the complex pathologies of protein conformational diseases.Many neurodegenerative diseases are characterized by protein misfolding and aggregation (15). Although the underlying disease origins may be genetically inherited or manifest sporadically, as exemplified by Huntington disease and ALS, respectively, the pathologies of these maladies all share the common molecular occurrence of protein aggregation (6). A network of protein folding and clearance mechanisms (the proteostasis network) is proposed to maintain a healthy proteome for normal cellular function (7, 8). Central to the proteostasis network are molecular chaperones and cochaperones, a diverse group of proteins that modulate the synthesis, folding, transport, and degradation of proteins (7). The conformations of aggregation-prone proteins are subject to multiple layers of regulation by the proteostasis network; however, as evidenced by the widespread pathologies of protein conformational diseases, the aggregation propensity of proteins associated with these diseases ultimately overwhelms the proteostasis machineries, thus initiating a cascade of cellular dysfunction (911).It is increasingly common for diseases of protein aggregation to be described as the result of gain-of-function toxicity. This toxicity is largely attributed to the dominant appearance of diverse aggregate species and the subsequent aberrant association of various proteostasis network components and other metastable proteins with these aggregates. This position is supported by experiments using immunohistochemical, biochemical, and MS methods on diseased patient tissues, as well as on numerous cellular and animal model systems (1216). Some of these molecular interactions, such as those between aggregates and proteasomal subunits, appear irreversible, suggesting a permanent sequestration of these proteins. The association of molecular chaperones with aggregates, on the other hand, appears transient (17, 18), indicating that chaperones may be functionally recognizing aggregates as substrates for potential disaggregation and refolding (19).Beyond refolding of toxic misfolded proteins, chaperones are also essential for the folding of endogenous metastable client proteins, as well as in the assembly and disassembly of functional protein complexes. Thus, chaperones regulate a wide range of essential cellular processes, including gene expression, vesicular trafficking, and signal transduction (2025). This dual role of chaperones suggests that a “competition” may arise between aggregates and endogenous protein clients for finite chaperone resources in situations where aggregates have accumulated. It has been proposed that such an imbalance may trigger the onset of many neurodegenerative diseases (10, 26), and recent studies report that polyglutamine (polyQ)-based aggregates can sequester and inhibit the function of a low-abundance cochaperone, Sis1p/DNAJB1, in protein degradation (27).Here, we show that diverse disease-associated aggregates sequester the highly abundant major chaperone heat shock cognate protein 70 (HSC70) to the point of functional collapse of an essential cellular process, clathrin-mediated endocytosis (CME). Importantly, aggregate-driven CME inhibition is reversible and can be rescued by nominally increasing HSC70 levels. Aggregate-driven chaperone depletion may help explain the phenotypic complexities displayed in protein conformational diseases.  相似文献   
17.
Association between hippocampal volume and serum adiponectin in patients with type 2 diabetes mellitus     
Masaki T  Anan F  Shimomura T  Fujiki M  Saikawa T  Yoshimatsu H 《Metabolism: clinical and experimental》2012,61(8):1197-1200
Type 2 diabetes mellitus (DM) is associated with cognitive dysfunction and hippocampus volume. The aim of the present study was to test the hypothesis that the level of the adipocytokine adiponectin correlates with hippocampus volume and insulin resistance in patients with type 2 DM. A total of 45 patients with type 2 DM were divided into two groups: a low adiponectin group and a normal adiponectin group. Hippocampus volume was measured by computer-assisted analysis using a magnetic resonance imaging (MRI) voxel-based specific regional analysis system developed for the study of Alzheimer's disease as the end point for assessment of hippocampus volume. Mean hippocampus volume was lower in the low adiponectin group than in the normal adiponectin group (P<.0001). Fasting serum concentrations of glucose (P<.05) and insulin (P<.0001), and homeostasis model assessment index (P<.0001), were all higher in the low adiponectin group than in the normal adiponectin group. Multiple regression analysis showed that hippocampus volume independently predicted serum adiponectin level. These results suggest that circulating levels of adiponectin are related to hippocampus volume in patients with type 2 DM.  相似文献   
18.
Contralateral glissonian pedicle occlusion in a case of portal vein tumor thrombosis     
Fukushima D  Sato K  Sekiguchi S  Kawagishi N  Akamatsu Y  Ogawa N  Takada I  Miyagi S  Kobayashi Y  Fujimori K  Satomi S 《Hepato-gastroenterology》2012,59(113):249-251
To dissect portal vein branches directly and encircle them separately is a common procedure that is performed to control back flow bleeding during operations for hepatocellular carcinoma with portal vein tumor thrombosis. However, this technique has an increased risk of injuring contralateral portal branches and disseminating thrombosis fragments to the remnant liver. We present an alternative technique using right-sided glissonian pedicle occlusion for hepatocellular carcinoma with left portal vein tumor thrombosis due to complex anatomical vasculatures of the hepatic pedicle. This technique would be very useful for liver resection of hepatocellular carcinoma with the major type of portal vein tumor thrombosis.  相似文献   
19.
Effective infliximab treatment for a recurrent type of acute intestinal graft-versus-host disease accompanied by steroid-induced depression     
Tamura S  Ishida H  Fujiki A  Yoshihara T  Kondo O  Inoue M  Kawa K  Kawabata K  Imamura T 《[Rinshō ketsueki] The Japanese journal of clinical hematology》2012,53(3):361-366
A 22-year-old man with chronic active Epstein-Barr virus infection underwent allogeneic bone marrow transplantation (allo-BMT) from an HLA two allele-mismatched unrelated donor. Ten months after allo-BMT, he developed protein-losing enteropathy following a respiratory syncytial virus infection. A diagnosis of a recurrent type of acute graft-versus-host disease (GVHD) was made based on the histopathological findings, such as the infiltration of T lymphocytes into the superficial epithelium and crypts, and apoptotic bodies in crypts. Although methylprednisolone (mPSL: 10 mg/kg) administration for two consecutive days improved gastrointestinal symptoms, acute pancreatitis and severe depression developed in association with corticosteroid treatment. Reduction of mPSL and administration of infliximab (5 mg/kg/dose, 3 times) resulted in rapid improvement of depression and pancreatitis without aggravating intestinal GVHD. Recent studies have demonstrated that tumor-necrosis-factor (TNF)-α is associated with not only GVHD but also depression and acute pancreatitis. In the present case, anti-TNF-α treatment enabled us to reduce corticosteroid dose without aggravating GVHD, which suggests that this approach might be effective for the treatment of depression and acute pancreatitis.  相似文献   
20.
Membranous ventricular septal aneurysm diagnosed by means of cardiac computed tomography     
Afaneh AB  Wymer DC  Kraft S  Winchester DE 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2012,39(3):450-451
  相似文献   
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