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1.
The entry into cells of human rhinovirus 2 (HRV 2) and murine encephalomyocarditis (EMC) virus was studied by the use of light-sensitive virus grown in the presence of acridine orange (HRV 2) and neutral red (EMC). HeLa cells were protected against infection with HRV 2 by NH4Cl, monensin, and other compounds known to increase the pH of intracellular vesicles. Preincubation of the cells with the same compounds reduced the ability of the cells to bind [35S]methionine-labeled HRV 2, apparently due to inhibition of recycling of endocytosed receptors back to the cell surface. The cells were also protected against infection when HRV 2 was bound to cells on ice and the cells were then incubated at 37° with the different compounds. This indicates that low pH is also necessary for some event in the entry process taking place after the virus is bound to the cells. In contrast, compounds which increase the pH in acidic intracellular compartments did not protect mouse L-cells against infection with EMC-virus, and the entry of the virus was inhibited by low pH in the medium. This inhibition was partly overcome by the presence of the ionophore monensin, which elevates the pH in endosomes and lysosomes. Possibly, EMC virus enters the cytosol from vesicles with neutral or slightly alkaline pH.  相似文献   
2.
We investigated mechanisms resulting in low bone mineral density (BMD) and susceptibility to fracture by comparing noncoding RNAs (ncRNAs) in biopsies of non–weight-bearing (NWB) iliac (n = 84) and weight bearing (WB) femoral (n = 18) postmenopausal bone across BMDs varying from normal (T-score > −1.0) to osteoporotic (T-score ≤ −2.5). Global bone ncRNA concentrations were determined by PCR and microchip analyses. Association with BMD or fracture, adjusted by age and body mass index, were calculated using linear and logistic regression and least absolute shrinkage and selection operator (Lasso) analysis. At 10% false discovery rate (FDR), 75 iliac bone ncRNAs and 94 femoral bone ncRNAs were associated with total hip BMD. Eight of the ncRNAs were common for the two sites, but five of them (miR-484, miR-328-3p, miR-27a-5p, miR-28-3p, and miR-409-3p) correlated positively to BMD in femoral bone, but negatively in iliac bone. Of predicted pathways recognized in bone metabolism, ECM-receptor interaction and proteoglycans in cancer emerged at both sites, whereas fatty acid metabolism and focal adhesion were only identified in iliac bone. Lasso analysis and cross-validations identified sets of nine bone ncRNAs correlating strongly with adjusted total hip BMD in both femoral and iliac bone. Twenty-eight iliac ncRNAs were associated with risk of fracture (FDR < 0.1). The small nucleolar RNAs, RNU44 and RNU48, have a function in stabilization of ribosomal RNAs (rRNAs), and their association with fracture and BMD suggest that aberrant processing of rRNAs may be involved in development of osteoporosis. Cis-eQTL (expressed quantitative trait loci) analysis of the iliac bone biopsies identified two loci associated with microRNAs (miRNAs), one previously identified in a heel-BMD genomewide association study (GWAS). In this comprehensive investigation of the skeletal genetic background in postmenopausal women, we identified functional bone ncRNAs associated to fracture and BMD, representing distinct subsets in WB and NWB skeletal sites. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.  相似文献   
3.

Background

Obesity is associated with reduced pulmonary function. We evaluated pulmonary function and status of asthma and obstructive sleep apnoea syndrome (OSAS) before and 5 years after bariatric surgery.

Methods

Spirometry was performed at baseline and 5 years postoperatively. Information of asthma and OSAS were recorded. Of 113 patients included, 101 had undergone gastric bypass, 10 duodenal switch and 2 sleeve gastrectomy.

Results

Eighty (71 %) patients were women, mean preoperative age was 40 years and preoperative weight was 133 kg in women and 158 kg in men. Five years postoperatively, weight reduction was 31 % (42 kg; p?<?0.001) in women and 24 % (38 kg; p?<?0.001) in men. Forced expiratory volume in 1 s (FEV1) increased 4.1 % (116 ml; p?<?0.001) in women and 6.7 % (238 ml; p?=?0.003) in men. Forced vital capacity (FVC) increased 5.8 % (209 ml; p?<?0.001) in women and 7.6 % (349 ml; p?<?0.001) in men. Gender and weight loss were independently associated with the improvements in FEV1 and FVC. At follow-up, FEV1 had increased 36 % of the difference towards the estimated normal FEV1, and there was a corresponding 70 % recovery of FVC. These improvements occurred despite an expected decline in pulmonary function by age during the study period. Of the asthmatics and OSAS patients, 48 and 80 %, respectively, were without symptoms 5 years postoperatively.

Conclusions

Pulmonary function measured with spirometry was significantly improved 5 years after bariatric surgery, despite an expected age-related decline during this period. Symptoms of asthma and OSAS also improved.  相似文献   
4.
Interaction between the immune system and cancer allows for the use of biological response modifiers, e.g. OK-432, in cancer therapy. OK-432, penicillin-killed Streptococcus pyogenes, is used in treating carcinomas, but also lymphangiomas. We have studied the role of monocytes (MOs) in the immune response to OK-432 by examining IL-6 and tumour necrosis factor (TNF)-α secretion after in vitro MO stimulation with OK-432, to some extent in comparison with lipoteichoic acid (LTA) and lipopolysaccharide (LPS). LTA stimulation of whole blood gave IL-6 but not TNF-α secretion, as previously shown with OK-432 stimulation, whereas both cytokines were secreted following LPS stimulation. Addition of the MAPK kinase (MAPKK) MEK inhibitor U0126 inhibited IL-6/TNF-α secretion in a dose-dependent manner. Flow cytometry and to some extent Western blot (Wb) analyses showed that MAPK ERK, located downstream of MEK1/2, is predominantly phosphorylated at isolation from peripheral blood. Addition of the p38 MAP kinase inhibitor SB202190 decreased MO IL-6/TNF-α production upon OK-432 stimulation in a dose-dependent manner. Addition of the MAPK JNK inhibitor SP600125 did not systematically change the MO IL-6/TNF-α OK-432 response. Flow cytometry showed that when stimulating the MOs before isolation from blood, LPS yielded ERK phosphorylation and LPS/LTA p38 phosphorylation, whereas OK-432 had no effects on phosphorylation levels. In conclusion, we have shown that OK-432 resembles TLR2 more than TLR4 stimulation of MOs and depends on MAPKK MEK and MAPK p38, but not on JNK phosphorylation. The MEK and p38 MO OK-432 stimulation dependence is possibly related to the differentiation of cells of the MO lineage.  相似文献   
5.
This report describes a patient with a perihilar mass and mediastinal lymphadenopathy mimicking advanced lung cancer. The patient, a 45-year old regular smoker, was admitted to hospital for dyspnea and tachyarrhythmia, and during hospitalization he was diagnosed with severe rheumatic mitral valve stenosis (MVS) and aortic regurgitation as well as pulmonary venous hypertension. Surgical valve replacement and removal of an atrial thrombus was delayed considerably by diagnostic work-up for suspected malignancy. After cardiac surgery had been performed, recovery was uneventful. On follow-up 1 year later, echocardiography showed well-functioning prosthetic mitral and aortic valves, and normal findings on chest X-ray. Perihilar masses and mediastinal lymphadenopathy presented in this case constitute infrequent yet established findings in MVS, resulting from pulmonary venous congestion and hypertension, and focal lymphedema.  相似文献   
6.
A Sundan  K Sandvig  S Olsnes 《Cancer research》1984,44(11):4919-4923
A number of mouse and rat cells and their virus-transformed counterparts were tested for sensitivity to Pseudomonas aeruginosa exotoxin A (PEA). In each case, the transformed cells were considerably less sensitive than were the nontransformed cells. In the presence of trifluoperazine, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide, or retinoic acid, the transformed cells became as sensitive as the nontransformed cells, whereas these drugs had little or no effect on the sensitivity to PEA of the nontransformed cells. Temperature-sensitive virus-transformed normal rabbit kidney cells were sensitized to PEA by N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide, when these cells were grown as the transformed phenotype, whereas the nontransformed phenotype could not be sensitized. The possibility is discussed that upon malignant transformation a process which is dependent upon calmodulin or protein kinase C strongly decreases the sensitivity of the cells to PEA.  相似文献   
7.
Neuropsychological tests were used to evaluate possible central nervous system dysfunction in patients treated with chemotherapy. Ninety-five patients with non-small cell lung cancer limited disease were randomized to either radiotherapy (2.8 Gy × 15) or combination chemotherapy with cisplatin and etoposide. In order to evaluate cognitive functions three neuropsychological tests were applied: Trail Making, Benton Visual Retention Test and Verbal Learning. Changes in the patients' test scores before and after treatment were compared. The chemotherapy patients showed reduced performance on some of the neuropsychological tests compared to the radiotherapy group. This indicates a treatment related effect on the central nervous system, possibly caused by the combination chemotherapy.  相似文献   
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10.
The Norwegian water column monitoring program investigates the biological effects of offshore oil and gas activities in Norwegian waters. In three separate surveys in 2006, 2008, and 2009, bioaccumulation and biomarker responses were measured in mussels (Mytilus edulis) and Atlantic cod (Gadus morhua) held in cages at known distances from the produced water (PW) discharge at the Ekofisk oil field. Identical monitoring studies performed in all three years have allowed the biological effects and bioaccumulation data to be compared, and in addition, enabled the potential environmental benefits of a PW treatment system (CTour), implemented in 2008, to be evaluated. The results of the 2009 survey showed that caged animals were exposed to low levels of PW components, with highest tissue concentrations in mussels located closest to the PW discharge. Mussels located approximately 1-2 km away demonstrated only background concentrations of target compounds. Concentrations of polycyclic aromatic hydrocarbons (PAH) and alkyl phenol (AP) metabolites in the bile of caged cod were elevated at stations 200-250 m from the discharge. There was also a signal of exposure relative to discharge for the biomarkers CYP1A in fish and micronuclei in mussels. All other fish and mussel biomarkers showed no significant exposure effects in 2009. The mussel bioaccumulation data in 2009 indicated a lower exposure to the PW effluent than seen previously in 2008 and 2006, resulting in an associated general improvement in the health of the caged mussels. This was due to the reduction in overall discharge of PW components (measured as oil in water) into the area in 2009 compared to previous years as a result of the improved PW treatment system.  相似文献   
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