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21.
Aberrant crypt focus promotion and glucose intolerance: correlation in the rat across diets differing in fat, n-3 fatty acids and energy 总被引:1,自引:0,他引:1
Koohestani N; Chia MC; Pham NA; Tran TT; Minkin S; Wolever TM; Bruce WR 《Carcinogenesis》1998,19(9):1679-1684
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994)
and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the
striking similarity in lifestyle risk factors for colorectal cancer and
insulin resistance, proposed that the hyperinsulinemia, glycemia and
hypertriglyceridemia associated with insulin resistance promotes colon
cancer. To compare the effect of diet on colon cancer promotion and insulin
resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids
and energy in pairwise comparisons on average size of aberrant crypt foci
(ACF) and on glucose intolerance in the same animals in a single
experiment. Diets high in fat and energy increased and diets with increased
n-3 fatty acids and calorie restriction decreased both ACF growth and
glucose intolerance compared with control diets. The measures of promotion
of colon cancer and insulin resistance were strongly correlated (n = 98, r
= 0.67, P < 0.001). In addition, both were highly correlated with daily
energy intake (r = 0.62 and 0.66) and were also correlated with basal
(post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P <
0.01). We concluded that ACF growth and glucose intolerance are correlated
for a wide range of diets and that increased circulating energy (glucose
and triglycerides) may lead to both colon cancer promotion and insulin
resistance.
相似文献
22.
Adriano Mendes Olivia Lentsoane Mushal Allam Zamantungwaka Khumalo Arshad Ismail Jacobus A. W. Coetzer Marietjie Venter 《Viruses》2022,14(7)
Bagaza virus (BAGV), a member of the Ntaya serogroup in the Flavivirus genus of the Flaviviridae, was isolated from the brain tissue of a Himalayan monal pheasant that died following neurological signs in Pretoria, South Africa in 2016. Next-generation sequencing was carried out on this isolate resulting in a genome sequence of 10980nt. The full genome sequence of this isolate, designated ZRU96-16, shared 98% nucleotide identity with a BAGV isolate found in Culex univitattus mosquitoes from Namibia and 97% nucleotide identity with a Spanish BAGV sequence isolated from an infected partridge. In total, seven amino acid variations were unique to ZRU96-16 after alignment with other BAGV and Israel turkey meningoencephalomyelitis (ITV) genomes. The 3′UTR sequence of ZRU96-16 was resolved with sufficient detail to be able to annotate the variable and conserved sequence elements within this region. Multiple sequence alignment of the 3′UTR suggested that it could be useful in lineage designation as more similar viruses carried similar mutations across this region, while also retaining certain unique sites. Maximum likelihood phylogenetic analysis revealed two clusters containing both BAGV and ITVs from Europe, the Middle East and Africa. Broadly, temporal clustering separated isolates into two groups, with one cluster representing viruses from the 1960–2000’s and the other from 2010 onwards. This suggests that there is consistent exchange of BAGV and ITV between Europe and Africa. This investigation provides more information on the phylogenetics of an under-represented member of the Flaviviridae and provides an avenue for more extensive research on its pathogenesis and geographic expansion. 相似文献
23.
L. Chandler K.E. Park O. Allam M.A. Mozaffari S. Khetpal J. Smetona N. Pourtaheri X. Lu J.A. Persing M. Alperovich 《International journal of oral and maxillofacial surgery》2021,50(8):1040-1046
The decision about which metopic synostosis patients should undergo surgery remains controversial. Multiple measures for radiographic severity have been developed in order to determine the optimal criteria for treatment. The aim of this study was to perform an extensive craniomorphometric analysis of patients who underwent surgery for metopic synostosis to validate and compare the various severity scales developed for this non-syndromic craniosynostosis. A comparative morphometric analysis was performed using computed tomography scans of preoperative metopic synostosis patients (n = 167) and normal controls (n = 44). Measurements included previous and newly developed metopic severity indices. Volumetric and area analyses were used to determine the degree of anterior cranial area and potential volume restrictions. Of the severity indices measured, the frontal angle, endocranial bifrontal angle (EBF), adjusted EBF (aEBF), anterior cranial fossa angle, horizontal cone angle, and bitemporal/biparietal distance ratio were significantly different in the metopic subjects relative to controls overall. However, metopic index, orbital rim angle, foramen ovale distance, and cranial volume exhibited no significant difference from controls. Only the frontal angle and aEBF correlated with the changes in anterior cranial dimensions observed in metopic synostosis. In conclusion, the frontal angle and aEBF provide the most accurate measures of severity in metopic synostosis. 相似文献
24.
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26.
Hassan Waleed A. Medhat Basma M. Youssef Maha M. Farag Yomna Mostafa Noha Alnaggar Alshaimaa R. Behiry Mervat E. Abdel Noor Rasha A. Allam Riham S. H. M 《Clinical rheumatology》2021,40(4):1599-1610
Clinical Rheumatology - To investigate the characteristics, evolution, and visual outcome of non-infectious uveitis. Records of 201 patients with non-infectious uveitis (136 (67.7%) males and 84... 相似文献
27.
I H Allam F M Feinsod R M Scott C J Peters A J Saah S A Ghaffar S el Said M A Darwish 《The American journal of tropical medicine and hygiene》1986,35(5):1055-1060
Rift Valley fever (RVF) surveillance was carried out in the Nile Delta by monitoring mobile and stationary sheep flocks for antibodies to RVF virus. Sheep are known to be susceptible to RVF virus infection and experienced severe morbidity in 1977 and 1978 when RVF was epidemic in Egypt. Four hundred six sheep in 32 flocks were surveyed during 1984. Twenty-four sheep from 7 flocks had antibodies to RVF virus detected by hemagglutination inhibition and plaque reduction neutralization tests. Antibodies were found primarily in sheep greater than 3 years of age, although 1- and 2-year-old sheep were included in the sample. No seroconversion was observed among 177 seronegative sheep that were bled successively for a period of 10 months. These results indicate that epizootic RVF was probably not present in the Nile Delta during 1984. 相似文献
28.
Ahmed E. Allam Hamdy K. Assaf Heba Ali Hassan Kuniyoshi Shimizu Yaseen A. M. M. Elshaier 《RSC advances》2020,10(50):29983
3′-Hydroxy-4′-methoxy-chroman-7-O-β-d-glucopyranoside 4 was first isolated from a natural source, together with three known compounds, the ferulic acid heptyl ester 1, naringenin 2, and 4,2′,4′-trihydroxy-6′-methoxychalcone-4′-O-β-d-glucopyranoside 3, which were isolated from peach [Prunus persica (L.) Batsch] fruits. These compounds were subjected to different virtual screening strategies in order to examine their activity to combat the COVID-19 outbreak. The study design composed of some major aspects: (a) docking with main protease (Mpro), (b) docking with spike protein, (c) 3D shape similarity study (Rapid Overlay Chemical Similarity-ROCS) to the clinically used drugs in COVID-19 patients, and finally, (d) the rule of five and the estimated pre-ADMT properties of the separated flavonoids. Docking study with Mpro of SARS-CoV-2 (PDB ID:6LU7, and 6Y2F) showed that compound 3, its aglycone part, and compound 4 have a strong binding mode to a protease receptor with key amino acids, especially Gln:166AA, and having a similar docking pose to co-crystalized ligands. Docking with the spike protein of SARS-CoV-2 illustrated that compounds 3 and 4 have a good binding affinity to PDB ID:6VSB through the formation of HBs with Asp:467A and Asn:422A. According to ROCS analysis, compounds 1, 3, and 4 displayed high similarities to drugs that prevent SARS-Co2 entry to the lung cells or block the inflammatory storm causing lung injury. Compounds 3 and 4 are good candidates for drug development especially because they showed predicted activity against SARS-CoV-2 through different mechanisms either by preventing genome replication or by blocking inflammatory storm that trigger lung injury. These compounds were isolated from peach fruit, and the study supports data and continues with the recommendation of peach fruits in controlling and managing COVID-19 cases.3′-Hydroxy-4′-methoxy-chroman-7-O-β-d-glucopyranoside 4, together with three known compounds, ferulic acid heptyl ester 1, naringenin 2, and 4,2′,4′-trihydroxy-6′-methoxychalcone-4′-O-β-d-glucopyranoside 3, was isolated from peach fruits. 相似文献
29.
Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro. 相似文献
30.
Ramanjaneyulu Allam Michel H. Maillard Aubry Tardivel Vijaykumar Chennupati Hristina Bega Chi Wang Yu Dominique Velin Pascal Schneider Kendle M. Maslowski 《The Journal of experimental medicine》2015,212(3):369-383
NLR family apoptosis inhibitory proteins (NAIPs) belong to both the Nod-like receptor (NLR) and the inhibitor of apoptosis (IAP) families. NAIPs are known to form an inflammasome with NLRC4, but other in vivo functions remain unexplored. Using mice deficient for all NAIP paralogs (Naip1-6Δ/Δ), we show that NAIPs are key regulators of colorectal tumorigenesis. Naip1-6Δ/Δ mice developed increased colorectal tumors, in an epithelial-intrinsic manner, in a model of colitis-associated cancer. Increased tumorigenesis, however, was not driven by an exacerbated inflammatory response. Instead, Naip1-6Δ/Δ mice were protected from severe colitis and displayed increased antiapoptotic and proliferation-related gene expression. Naip1-6Δ/Δ mice also displayed increased tumorigenesis in an inflammation-independent model of colorectal cancer. Moreover, Naip1-6Δ/Δ mice, but not Nlrc4-null mice, displayed hyper-activation of STAT3 and failed to activate p53 18 h after carcinogen exposure. This suggests that NAIPs protect against tumor initiation in the colon by promoting the removal of carcinogen-elicited epithelium, likely in a NLRC4 inflammasome-independent manner. Collectively, we demonstrate a novel epithelial-intrinsic function of NAIPs in protecting the colonic epithelium against tumorigenesis.Inflammatory bowel disease (IBD) is an important risk factor that favors the development and progression of colitis-associated cancer (CAC; Eaden et al., 2001; Terzić et al., 2010; Rubin et al., 2013). Even in the absence of overt inflammatory disease in colorectal cancer (CRC), loss of barrier function in the tumor epithelium enables translocation of microbial products into tumor tissue. This triggers the activation of lamina propria immunocytes and colonic epithelial cells via pattern-recognition receptors (PRRs) to produce cytokines and chemokines. Those factors then promote tumor growth and mediate recruitment of further immune cells (Grivennikov et al., 2012; Mueller, 2012). Alternatively, epithelial innate immune components could be subverted during tumorigenesis and influence tumor growth independently. Although cytokine/chemokine-mediated modulation of tumor growth has been described, the role of epithelial-intrinsic, innate immune components still remains elusive.Several Nod-like receptors (NLRs) have previously been implicated in colon inflammation and tumorigenesis, mostly in protective roles (Allen et al., 2010; Hu et al., 2010; Chen et al., 2011; Elinav et al., 2011; Zaki et al., 2011; Carvalho et al., 2012). In some cases, this has been attributed to reduced inflammasome-mediated release of IL-18, which is protective for the colonic epithelium (Allen et al., 2010; Dupaul-Chicoine et al., 2010). In other cases, noninflammasome-mediated factors were found to protect mice against CAC development. For example, NLRP12 was protective against colonic inflammation and tumorigenesis by dampening NF-κB and ERK activation in macrophages (Zaki et al., 2011). However, several discrepancies also exist, as illustrated by Caspase-1–deficient mice, which display increased colon tumorigenesis. In one study, this was dependent on NLRC4 and was epithelial intrinsic rather than inflammation mediated (Hu et al., 2010), whereas, in another study, increased tumorigenesis involved NLRP3 and was inflammation and hematopoietic cell–dependent (Allen et al., 2010). Such discrepancies are suggested to arise from differences in microbiota between facilities or use of WT mice from external sources (Ubeda et al., 2012), but could also arise from opposing functions of inflammasome components in different tissues, which has been demonstrated in a skin tumorigenesis model (Drexler et al., 2012).The physiological function of the NLR protein NAIP (NLR family apoptosis inhibitory protein, previously known as neuronal apoptosis inhibitory protein) is not fully characterized, mainly because mice have several possibly redundant Naip paralogs (e.g., 4 functional and 2 noncoding Naip genes in the C57BL/6 genome; Yaraghi et al., 1998; Endrizzi et al., 2000; Growney and Dietrich, 2000). Humans also have several NAIP genes, only one of which is full length (Schmutz et al., 2004; Romanish et al., 2009). NAIPs are intracellular, cytosolic proteins with a tripartite structure; three N-terminal baculovirus inhibitor of apoptosis (IAP) protein repeat (BIR) domains, a central NACHT domain and C-terminal leucine rich-repeat (LRR) domains. The latter two domains group NAIPs to the NLR family of proteins. Indeed, NAIPs are best characterized for their inflammasome function. Mouse and human NAIPs are involved in the detection of intracellular pathogens, such as Salmonella, and activation of the NLRC4 inflammasome, inducing pyroptosis and caspase-1–mediated cleavage of IL-1β and IL-18 (Kofoed and Vance, 2011; Zhao et al., 2011; Rayamajhi et al., 2013; Yang et al., 2013). In mice, NAIP paralogs provide specificity to different bacterial components (Kofoed and Vance, 2011; Zhao et al., 2011). In vivo, the NAIP5-NLRC4 inflammasome was required for sepsis-induced mortality by an Escherichia coli pathobiont or by systemic delivery of intracellular-targeted flagellin, although partial redundancy to other Naip paralogs was apparent (Ayres et al., 2012; von Moltke et al., 2012).NAIPs also belong to the IAP family due to three N-terminal BIR domains; but whether they actually function as inhibitors of apoptosis is controversial. Some studies show direct binding and inhibition of caspase-3 and -9 (Maier et al., 2002; Davoodi et al., 2004, 2010), but others do not (Roy et al., 1997). Also, NAIPs lack certain caspase-interaction residues within the BIR domains that would be necessary for direct inhibition of caspases, raising concern about whether NAIP can inhibit caspases in physiological settings (Scott et al., 2005; Eckelman and Salvesen, 2006; Eckelman et al., 2006). Additionally, NAIPs mediate inflammasome-induced caspase-1 activation and induction of pyroptosis via NLRC4, which is contrary to the suggested inhibitor of apoptosis function (Kofoed and Vance, 2012). BIR domains, however, can mediate a broad range of protein–protein interactions and therefore could be implicated in diverse cellular functions in addition to inhibition of caspases. In NAIPs, the BIR domains appeared to be necessary for NLRC4 inflammasome formation and activation of caspase-1 (Kofoed and Vance, 2011).A mouse model lacking all Naip paralogs has not been available, preventing definitive analysis of NAIPs physiological function. In this study, we describe the first complete Naip1-6 knockout mice and demonstrate a crucial role for NAIPs in preventing colonic tumor initiation and progression. 相似文献