Post–conditioning reduces infarct size in the isolated rat heart: Role of coronary flow and pressure and the nitric oxide/cGMP pathway

We aimed to assess the role of the nitric oxide (NO)–cGMP pathway in cardioprotection by brief intermittent ischemias at the onset of reperfusion (i.e., post–conditioning (Post–con)). We also evaluated the role of coronary flow and pressure in Post–con. Rat isolated hearts perfused at constant– flow or –pressure underwent 30 min global ischemia and 120 min reperfusion. Post–con obtained with brief ischemias of different duration (modified, MPost–con) was compared with Post–con obtained with ischemias of identical duration (classical, C–Post–con) and with ischemic preconditioning (IP). Infarct size was evaluated using nitro–blue tetrazolium staining and lactate dehydrogenase (LDH) release. In the groups, NO synthase (NOS) or guanylyl–cyclase (GC) was inhibited with LNAME and ODQ, respectively. In the subgroups, the enzyme immunoassay technique was used to quantify cGMP release. In the constant–flow model, M–Post–con and C–Post–con were equally effective, but more effective than IP in reducing infarct size. The cardioprotection by M–Post–con was only blunted by the NOS–inhibitor, but was abolished by the GC–antagonist. Post–ischemic cGMP release was enhanced by MPost–con. In the constant–pressure model IP, M–Post–con and C–Post–con were equally effective in reducing infarct size. Post–con protocols were more effective in the constant–flow than in the constant–pressure model. In all groups, LDH release during reperfusion was proportional to infarct size. In conclusion, Post–con depends upon GC activation, which can be achieved by NOS–dependent and NOS–independent pathways. The benefits of M– and CPost–con are similar. However, protection by Post–con is greater in the constant–flow than in the constant–pressure model.     

Dendritic cells in multiple sclerosis lesions: maturation stage, myelin uptake, and interaction with proliferating T cells

In multiple sclerosis (MS), dendritic cells (DCs) recruited to the central nervous system (CNS) are thought to be involved in the regulation of autoimmune responses directed against myelin antigens. To better understand the role of DCs in CNS inflammation, we performed a detailed immunohistochemical analysis of DC maturation markers and of DC relationship to CNS-infiltrating T cells in autopsy brain tissue of patients with MS. We also investigated the presence of DCs containing myelin debris in MS lesions. Myeloid DC subsets were identified using the following markers: CD1a for immature DCs; DC-SIGN for immature and mature DCs; and fascin, CD83, DC-LAMP, and CCR7 for mature DCs. The most common finding was the presence of cells expressing DC-SIGN and containing myelin components in the perivascular cuffs of early active and chronic (both active and inactive) MS lesions. Perivascular CD1a DCs were detected in active lesions in only one of 10 patients with MS who were examined. Although less numerous than DC-SIGN DCs, cells expressing mature DC markers were consistently detected in the inflamed meninges and perivascular cuffs of most active lesions examined. CCR7 immunostaining was predominantly confined to activated microglia at the lesion edges. Some perivascular DC-SIGN cells were found in close proximity to or contacting rare proliferating lymphocytes, most of which expressed the DC-SIGN ligand ICAM-3 and CD8. These data suggest that DCs recruited and maturing in MS lesions, where self-antigens are made available by continuous myelin destruction, may contribute to the local activation and expansion of presumably pathogenic T cells.     

C9ORF72 hexanucleotide repeat expansions in the Italian sporadic ALS population

It has been recently reported that a large proportion of patients with familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are associated with a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72. We have assessed 1757 Italian sporadic ALS cases, 133 from Sardinia, 101 from Sicily, and 1523 from mainland Italy. Sixty (3.7%) of 1624 mainland Italians and Sicilians and 9 (6.8%) of the 133 Sardinian sporadic ALS cases carried the pathogenic repeat expansion. None of the 619 regionally matched control samples (1238 chromosomes) carried the expansion. Twenty-five cases (36.2%) had behavioral FTD in addition to ALS. FTD or unspecified dementia was also detected in 19 pedigrees (27.5%) in first-degree relatives of ALS patients. Cases carrying the C9ORF72 hexanucleotide expansion survived 1 year less than cases who did not carry this mutation. In conclusion, we found that C9ORF72 hexanucleotide repeat expansions represents a sizeable proportion of apparent sporadic ALS in the Italian and Sardinian population, representing by far the most common mutation in Italy and the second most common in Sardinia.     

Treatment of progressive Hodgkin's disease with intensive chemoradiotherapy and autologous bone marrow transplantation

Twenty-six patients with progressive Hodgkin's disease after conventional chemotherapy received intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT); 19 also received additional involved-field radiotherapy. Twenty-one patients [81%, 95% confidence intervals (CI) 61% to 94%] attained complete (n = 18) or partial responses. Ten patients (38%, 95% CI 20% to 59%) are disease- free a median of 4.5 years later (range 3.5 to 7.0 years), including seven patients with continuous complete responses. The likelihood of overall response was not significantly influenced by any clinical or treatment variable examined. However, there was a trend favoring patients with higher Karnofsky scores, and higher scores were associated with attainment of complete responses (P = .06 and P = .02, respectively, Mann-Whitney U test). Both higher Karnofsky scores and shorter durations of disease before transplantation were associated with improved survival in a stepwise Cox multivariate analysis. The chief cause of failure was progression at sites previously involved with Hodgkin's disease. No patient relapsed in the marrow, and two of three patients with a history of marrow involvement with Hodgkin's disease achieved durable complete responses after transplantation. These data suggest that inadequate pretransplant conditioning, and not the reinoculation of occult tumor cells in the autologous marrow, caused most relapses. Fatal treatment-related toxicity occurred in six patients. Three patients died of idiopathic interstitial pneumonitis; each had previously received local mediastinal irradiation before intensive chemoradiotherapy. Intensive chemoradiotherapy and ABMT produces durable responses in some patients with Hodgkin's disease incurable with conventional therapy. Use of such therapies at the first sign of failure with conventional chemotherapy and development of more effective conditioning regimens should further improve results.     

Interleukin-4 inhibits indoleamine 2,3-dioxygenase expression in human monocytes

Indoleamine 2,3-dioxygenase (IDO), a flavin-dependent enzyme that catalyzes the conversion of tryptophan to kynurenine, is induced in peripheral blood mononuclear cells by interferon-gamma (IFN gamma). Interleukin-4 (IL-4) is a cytokine that modulates the functional properties of monocytes/macrophages, and we investigated the effects of IL-4 on IDO. We showed that IL-4 inhibited the induction of IDO mRNA and IDO activity by IFN gamma in human monocytes. The inhibitory effect was evident with as little as 2 U/mL of IL-4. These results provide the first evidence that a cytokine can provide a negative signal for IDO expression and that IL-4 can influence the catabolism of tryptophan.     

Congenital middle-ear deafness: CT study

Computed tomography (CT) was used to study 25 patients with congenital conductive hearing loss and normal external auditory canals. Deformities were subdivided according to ossicular, fenestral, and cholesteatomatous origin. Isolated ossicular deformities were found in 14 patients (five bilateral), cholesteatoma in eight, oval-window nondevelopment (with ossicular deformity) in one, and normal studies in two (congenital stapes fixation at the level of the annular ligament). Ossicular deformities may be subdivided into incudostapedial disconnections into incudostapedial disconnections (most common), malleoincudal fixations, and stapes fixations. Most are due to developmental anomaly of the first or second branchial arch. The stapes has a dual origin (second arch and otic capsule). A cholesteatoma is defined as congenital only if there is no history of otitis and the tympanic membrane is intact. In this series, six were in the middle ear proper, and two were within the attic beyond otoscopic view. Their CT appearance, with one exception, was essentially identical to that of acquired lesions.     

Characterization of the response to myelin basic protein in a non human primate model for multiple sclerosis

The common marmoset Callithrix jacchus (C. jacchus) is an outbred species characterized by a naturally occurring bone marrow chimerism and susceptibility to a form of experimental autoimmune encephalomyelitis (EAE) resembling multiple sclerosis (MS). T cell clones specific for the myelin antigen, myelin basic protein (MBP), can be derived from both naive and immunized marmosets and can adoptively transfer EAE to compatible chimeric siblings. Here, we demonstrate that several different antigenic determinants of MBP are recognized by these encephalitogenic T cell clones. Furthermore, PCR-based analysis of TCR Vbeta families does not show the preferential usage of any gene segment. Characterization of third complementarity determining regions (CDR3) fails to demonstrate a recurring motif characteristic of the T cell immune response to MBP in this species. Nevertheless, brief amino acid motifs are shared among marmoset clones and CDR3 sequences from MS samples. These data suggest that, due to its outbred condition, the C. jacchus marmoset mounts a diverse pathogenic response to MBP. However, the findings that certain CDR3 sequences are identically expressed in different animals, or by different T cell clones, suggest that MBP-specific T cell populations may be clonally expanded following chronic antigenic stimulation in vivo.     

Formic acid treatment exposes hidden neurofilament and tau epitopes in abnormal cytoskeletal filaments from patients with progressive supranuclear palsy and Alzheimer's disease.

In cases of progressive supranuclear palsy (PSP) and Alzheimer's disease (AD) the treatment of tissue sections with formic acid (FA) disclosed a neurofilament epitope in subcortical straight (SF) and paired helical (PHF) filaments. The same treatment produced a two-fold increase of tau-reactive neuropil threads and plaque-related neurites in AD cortical tissue. These findings indicate that epitopes of cytoskeletal proteins are hidden by the beta-pleated conformation of SF and PHF components. FA treatment should be used in immunohistochemical detection of intraneuronal abnormal cytoskeletal filaments.     

BMP2,3,4,5 mRNA在三叉神经中的表达分析

目的：明确 Ｂ Ｍ Ｐｓ 与外周神经的关系。方法：用原位杂交方法观察 Ｂ Ｍ Ｐ２,３,４,５ 的ｍ Ｒ Ｎ Ａ在三叉神经中的表达。结果：在外周神经（三叉神经）中均有 Ｂ Ｍ Ｐ２,３,４,５ ｍ Ｒ Ｎ Ａ 分布, Ｂ Ｍ Ｐ２,３,４,５ 的分布主要位于构成神经纤维髓鞘的雪旺细胞中;此外发现 Ｂ Ｍ Ｐ２ 在部分神经纤维中也有表达。结论：首次确定了 Ｂ Ｍ Ｐ２,３,４,５ 在外周神经中的表达和分布,揭示了 Ｂ Ｍ Ｐ２,３,４,５可能在外周神经的发育和再生以及形态结构的维持中发挥着调控作用。