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The translocon at the outer envelope membrane of chloroplasts (Toc) mediates the recognition and initial import into the organelle of thousands of nucleus-encoded proteins. These proteins are translated in the cytosol as precursor proteins with cleavable amino-terminal targeting sequences called transit peptides. The majority of the known Toc components that mediate chloroplast protein import were originally identified in pea, and more recently have been studied most extensively in Arabidopsis. With the completion of the tomato genome sequencing project, it is now possible to identify putative homologues of the chloroplast import components in tomato. In the work reported here, the Toc GTPase cDNAs from tomato were identified, cloned and analyzed. The analysis revealed that there are four Toc159 homologues (slToc159-1, -2, -3 and -4) and two Toc34 homologues (slToc34-1 and -2) in tomato, and it was shown that tomato Toc159 and Toc34 homologues share high sequence similarity with the comparable import apparatus components from Arabidopsis and pea. Thus, tomato is a valid model for further study of this system. The expression level of Toc complex components was also investigated in different tissues during tomato development. The two tomato Toc34 homologues are expressed at higher levels in non-photosynthetic tissues, whereas, the expression of two tomato Toc159 homologues, slToc159-1 and slToc159-4, were higher in photosynthetic tissues, and the expression patterns of slToc159-2 was not significantly different in photosynthetic and non-photosynthetic tissues, and slToc159-3 expression was limited to a few select tissues.

BACKGROUND: The diagnostic yield of light blue crest(LBC) sign, which was observed by narrow band imaging with magnification endoscopy(NBI-ME), in detecting gastric intestinal metaplasia(IM) has shown variable results. OBJECTIVE: We aimed to assess the diagnostic value of LBC under NBI-ME for detecting gastric IM. METHODS: We performed a literature search of the Medline/PubMed, Embase, Web of Science, Science Direct and the Cochrane Library Databases; and a meta-analysis of pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and SROC area under the curve, using fixed- and random-effects models, for the accuracy of LBC-based IM diagnosis. RESULTS: We initially included 4 articles, but excluded 1 article to counter significant heterogeneity. When pooled, the remaining 3 articles, which included 247 patients with 721 lesions, showed the following patterns in IM diagnosis: sensitivity: 0.90 (95% confidence interval [CI] 0.86-0.92); specificity: 0.90 (95% CI 0.86-0.93), positive likelihood ratio: 8.98 (95% CI 6.42-12.58), negative likelihood ratio: 0.12 (95% CI 0.09-0.16), and SROC area under the curve: 0.9560. LIMITATIONS: As the studies varied by their definitions for positive LBC, endoscopy types, biopsy protocols, race of patient cohort, and physicians' proficiency, some sample sizes were limited so that subgroup analyses could not be performed. CONCLUSION: We concluded that observing LBC under NBI-ME is an accurate and precise means of diagnosing gastric IM.

Hepatitis B virus (HBV) is hepatotropic and lymphotropic. HBV-infected individuals have an increased risk of developing malignant lymphoma, and the HBV infection rate in lymphoma patients is significantly higher than that in the general population. However, the exact mechanism and correlation between HBV infection and lymphoma onset and progression currently remain unclear. We retrospectively analyzed clinical data from non-Hodgkin's lymphoma (NHL) patients with different HBV infection statuses. The results showed that the HBV infection rate was significantly higher in patients with B-cell type and late stage of NHL. The chemotherapy efficacy for NHL patients with chronic active HBV infection was significantly lower than that for the patients with chronic inactive HBV infection, the patients with HBV carriers and the patients without HBV infection. In addition, the NHL chemotherapy activated HBV replication and caused significant liver dysfunction, which could further reduce the chemotherapy efficacy. Through Kaplan-Meier survival curve and log-rank analysis, we found that the HBV infection status in NHL patients was significantly correlated with the patients' progression-free survival (PFS) and overall survival (OS). Compared with the patients without HBV infection (PFS: 95% CI 47.915 to 55.640; OS: 95% CI 81.324 to 86.858), the PFS and OS of the patients with chronic active HBV infection were significantly shorter (PFS: 95% CI 9.424 to 42.589, P < 0.001; OS: 95% CI 42.840 to 82.259, P = 0.006). The study demonstrated that the sustained HBV replication in patients with chronic active HBV infection could be a key factor that influences the prognosis of NHL patients after chemotherapy, and thus may provide information for designing rational clinical treatments for NHL patients with different HBV infection statuses and improve the treatment efficacy and prognosis.

BACKGROUND: Genetic factors in the pathogenesis of cardiomyopathies have received a lot attention during the past two decades. Angiotensin I converting enzyme (ACE) insertion/deletion (I/D) polymorphisms were found to be associated with cardiomyopathies. However, the previous results were inconsistent. The current meta-analysis aims to examine the association of ACE I/D polymorphisms and dilated cardiomyopathy (DCM) or hypertrophic cardiomyopathy (HCM). METHODS: Eight studies on DCM (1387 controls and 977 patients) and eight studies on HCM (1055 controls and 827 patients) were included in this meta-analysis. RESULTS: The overall data showed no significant association between ACE I/D polymorphism and DCM risk. Further subgroup analysis by ethnicity also did not find a significantly increased risk for D allele carriers among East Asians and Europeans. However, the overall analysis suggested that the D allele carriers might be associated with increased risk of HCM (DD/ID vs. II: OR = 1.69, 95% CI 1.04-2.74, P = 0.03). CONCLUSION: In summary, the meta-analysis indicated that certain ACE I/D polymorphism might be associated with HCM but not DCM susceptibility. Given the limited sample sizes, further large multicenter case-control investigation is needed.

The epidemiology and possibly the etiology of bovine spongiform encephalopathy (BSE) have recently been recognized to be heterogeneous. In particular, three types [classical (C) and two atypical (H, L)] have been identified, largely on the basis of characteristics of the proteinase K (PK)-resistant core of the misfolded prion protein associated with the disease (PrP(res)). The present study was conducted to characterize the 17 Canadian BSE cases which occurred prior to November 2009 based on the molecular and biochemical properties of their PrP(res), including immunoreactivity, molecular weight, glycoform profile and relative PK sensitivity. Two cases exhibited molecular weight and glycoform profiles similar to those of previously reported atypical cases, one corresponding to H-type BSE (case 6) and the other to L-type BSE (case 11). All other cases were classified as C-type. PK digestion under mild and stringent conditions revealed a reduced protease resistance in both of these cases compared to the C-type cases. With Western immunoblotting, N-terminal-specific antibodies bound to PrP(res) from case 6 but not to that from case 11 or C-type cases. C-terminal-specific antibodies revealed a shift in the glycoform profile and detected a fourth protein fragment in case 6, indicative of two PrP(res) subpopulations in H-type BSE. No mutations suggesting a genetic etiology were found in any of the 17 animals by sequencing the full PrP-coding sequence in exon 3 of the PRNP gene. Thus, each of the three known BSE types have been confirmed in Canadian cattle and show molecular characteristics highly similar to those of classical and atypical BSE cases described from Europe, Japan and the USA. The occurrence of atypical cases of BSE in countries such as Canada with low BSE prevalence and transmission risk argues for the occurrence of sporadic forms of BSE worldwide.