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41.
The mineral levels in maternal serum change during pregnancy and may be correlated with those of newborn cord blood. The aim of this study was to evaluate the concentrations of calcium (Ca), magnesium (Mg), zinc (Zn), iron (Fe), and copper (Cu) in maternal blood before and after delivery and in umbilical cord vein and artery serum. The study was carried out in 64 Caucasian pregnant women who delivered in a district hospital in Greater Poland region, aged 28.1 ± 5.4 years, with a mean gestational age of 39.2 ± 1.3 weeks. Blood samples were taken from women 2–8 h before delivery and immediately after childbirth. The umbilical cord artery and vein blood of newborns was obtained immediately after childbirth. The levels of minerals in serum were determined by flame atomic absorption spectrometry. A significant drop in the concentrations of Mg (17.71 ± 1.51 vs 17.07 ± 1.61 μg/ml; p < 0.007), Fe (1.08 ± 0.46 vs 0.82 ± 0.35 μg/ml; p < 0.0004), and Zn (0.63 ± 0.17 vs 0.46 ± 0.16; p < 0.0001) in maternal serum was found after delivery. Moreover, higher levels of Ca, Fe, and Zn and lower levels of Cu were observed in the umbilical vein (Ca: 102.80 ± 7.80 μg/ml; p < 0.0001, Fe: 1.96 ± 0.43 μg/ml; p < 0.0001, Zn: 0.65 ± 0.16 μg/ml; p < 0.0001, Cu: 0.36 ± 0.09 μg/ml; p < 0.0001) and in the umbilical artery cord blood (Ca: 98.07 ± 8.18 μg/ml; p < 0.0001, Fe: 1.63 ± 0.30 μg/ml; p < 0.0001, Zn: 0.65 ± 0.15 μg/ml; p < 0.0001, and Cu: 0.36 ± 0.10 μg/ml; p < 0.0001) compared to the maternal serum (Ca: 85.05 ± 10.76 μg/ml, Fe: 0.82 ± 0.35 μg/ml, Zn: 0.46 ± 0.16 μg/ml, and Cu: 1.90 ± 0.35 μg/ml). Fe levels in the cord artery serum negatively correlated with blood loss during delivery (R = ?0.48; p = 0.01), while the Ca concentration in the maternal serum after birth decreased with the age of the women (R = ?0.25; p = 0.03). In conclusion, it seems that the process of birth alters the mineral levels in pregnant women’s blood. Moreover, it was found that blood loss and the age of the mother are associated with mineral concentrations in the maternal serum and cord artery blood.  相似文献   
42.
The Streptomyces lividans DnaA protein (73 kDa) consists, like the Escherichia coli DnaA protein (52 kDa), of four domains. The larger size of the S. lividans protein is due to an additional stretch of 120 predominantly acidic amino acids within domain II. The S. lividans protein was overproduced as a His-tagged fusion protein. The purified protein (isoelectric point, 5.7) has a weak ATPase activity. By DNase I footprinting studies, each of the 17 DnaA boxes (consensus sequence, TTGTCCACA) in the S. lividans oriC region was found to be protected by the DnaA fusion protein. Purified mutant proteins carrying a deletion of the C-terminally located helix-loop-helix (HLH) motif or with amino acid substitutions in helix A (L577G) or helix B (R595A) no longer interact with DnaA boxes. A substitution of basic amino acids in the loop of the HLH motif (R587A or R589A) entailed the formation of S. lividans mutant DnaA proteins with little or no capacity for binding to DnaA boxes. Thus, like in E. coli, the C-terminally located domain IV is absolutely necessary for the specific binding of DnaA. A mutant protein lacking a stretch of acidic amino acids corresponding to domain II is not affected in its DNA binding capacity. Whether the acidic domain II interacts with accessory proteins remains to be elucidated.  相似文献   
43.
Translocation of bacteria, primarily Gram-negative pathogenic flora, from the intestinal lumen into the circulatory system leads to sepsis. In newborns, and especially very low birth weight infants, sepsis is a major cause of morbidity and mortality. The results of recently conducted clinical trials suggest that lactoferrin, an iron-binding protein that is abundant in mammalian colostrum and milk, may be an effective agent in preventing sepsis in newborns. However, despite numerous basic studies on lactoferrin, very little is known about how metal saturation of this protein affects a host’s health. Therefore, the main objective of this study was to elucidate how iron-depleted, iron-saturated, and manganese-saturated forms of lactoferrin regulate intestinal barrier function via interactions with epithelial cells and macrophages. For these studies, a human intestinal epithelial cell line, Caco-2, was used. In this model, none of the tested lactoferrin forms induced higher levels of apoptosis or necrosis. There was also no change in the production of tight junction proteins regardless of lactoferrin metal saturation status. None of the tested forms induced a pro-inflammatory response in Caco-2 cells or in macrophages either. However, the various lactoferrin forms did effectively inhibit the pro-inflammatory response in macrophages that were activated with lipopolysaccharide with the most potent effect observed for apolactoferrin. Lactoferrin that was not bound to its cognate receptor was able to bind and neutralize lipopolysaccharide. Lactoferrin was also able to neutralize microbial-derived antigens, thereby potentially reducing their pro-inflammatory effect. Therefore, we hypothesize that lactoferrin supplementation is a relevant strategy for preventing sepsis.  相似文献   
44.
A population ofLactobacillus acidophilus variants that had partly or completely lost its nucleotide-synthesizing ability was isolated from the crops of chicks. The majority of these strains had a specific nutritional requirement for exogenous deoxycytidine or deoxycytidylic acid. Deoxycytidine at 0.5 µg/ml supported half-maximum growth. Deoxyadenosine and deoxyguanosine or their nucleotides could be substituted for deoxycytidine only in the presence of an excess of cytidylic acid. AnotherL. acidophilus variant, strain 42/8, had an identical need for these deoxycompounds but, in addition, required a high concentration of ribonucleotides. Any ribonucleotide was active, the requirement for half-maximal growth being 20–25 µg/ml.  相似文献   
45.
Associations between plants and fungi were an important and varied feature of early terrestrial ecosystems, but in most instances their biological functions remain poorly understood. We document a new species of fungus colonizing the rooting system of the early lycopod Asteroxylon mackiei, based on exceptionally well‐preserved fossils from the Rhynie Chert. We investigated historical petrographic thin sections using standard optical microscopy and confocal laser scanning microscopy. P alaeozoosporites renaultii gen. nov., sp. nov. colonized the inner cortex of the plant rooting system. The fungus had an aseptate thallus with isotomous or sympodial branching. The mycelium bore distinctive porate, globose to elongated structures that we interpret as zoosporangia and resting sporangia. Doubts remain over the precise systematic affinity of P. renaultii, which closely resembles chytrids. Whereas most of the Rhynie Chert plants developed symbiotic associations of the mycorrhizal type, it seems that this was not the case for Asteroxylon mackiei, which possessed the most evolved rooting system among the Rhynie Chert plants. We argue that the new root‐borne fungus was probably parasitic. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 201–213.  相似文献   
46.
The animals used in the experiment consisted of 411 aged (parous), and 171 maiden ewes (18 months old) and 17 rams. In total 357 observations were made during mating (272 on parous and 85 on maiden ewes). The average mating time for the parous ewes was 58.26 s, and for the maidens 97.0 s. The difference was highly significant (P < 0.01). Mean numbers of mounts per ejaculation for parous and maiden ewes were 2.17 and 2.53 respectively. The difference was highly significant (P < 0.01) and was caused, among other factors, by the reluctant standing attitude of maiden ewes. The results confirm that difficulties exist in the serving fo maiden ewes.The reproduction indices were calculated on the basis of service during the first oestrus in the mating season. The pregnancy rate was 56.45% for older ewes and 54.04% for maidens, the difference being not significant. The lambing rate was 113.3% and 110.3% for parous and maiden ewes respectively, the difference being statistically insignificant. The absence of divergence of reproduction indices between the two groups suggests that the difficulty in serving maiden ewes is due to their lack of reproductive experience which does not influence their reproductive capacity.  相似文献   
47.
The nasal polyp (NP) seems to represent the end-stage of longstanding inflammation in patients with chronic rhinosinusitis. The aim of our study has been to evaluate the presence of two regulatory cell populations in the microenvironment of NP: CD4+CD25high Foxp3+ (Treg) cells and B7-H4-expressing macrophages. Treg cells are actively able to inhibit T lymphocytes, while the population of B7-H4-expressing macrophages has recently been described as characterized by a regulatory function similar to that of Treg cells. For our study, we evaluated 14 NP tissue samples. The samples were divided into two main groups, eosinophilic (NP) and lymphocytic (NP), according to the predominant type of immune cell infiltration. The presence of Treg cells and B7-H4 positive macrophages in the samples was analyzed by FACS. Treg cells and B7-H4-expressing macrophages were identified in all the examined nasal polyps. The percentages of both Treg cells and of B7H4 positive cells found in the eosinophilic nasal polyps were higher than those found in the lymphocytic nasal polyps. Treg cells and B7H4+ macrophage subpopulations were present in the NP microenvironment and the alterations in their percentages were related to a distinct pattern of immune cell infiltration.  相似文献   
48.
Majka CG 《ZooKeys》2010,(51):73-83
The collection of maple sap for the production of maple syrup is a large commercial enterprise in Canada and the United States. In Canada, which produces 85% of the world's supply, it has an annual value of over $168 million CAD. Over 38 million trees are tapped annually, 6.5% of which use traditional buckets for sap collection. These buckets attract significant numbers of insects. Despite this, there has been very little investigation of the scale of this phenomenon and the composition of insects that are attracted to this nutrient source. The present paper reports the results of a preliminary study conducted on Prince Edward Island, Canada. Twenty-eight species of Coleoptera, Lepidoptera, and Trichoptera were found in maple sap buckets, 19 of which are known to be attracted to saps and nectars. The physiological role of sap feeding is discussed with reference to moths of the tribe Xylenini, which are active throughout the winter, and are well documented as species that feed on sap flows. Additionally, 18 of the 28 species found in this study are newly recorded in Prince Edward Island.  相似文献   
49.

Background

Mutations in the DNAI1 gene, encoding a component of outer dynein arms of the ciliary apparatus, are the second most important genetic cause of primary ciliary dyskinesia (PCD), the genetically heterogeneous recessive disorder with the prevalence of ~1/20,000. The estimates of the DNAI1 involvement in PCD pathogenesis differ among the reported studies, ranging from 4% to 10%.

Methods

The coding sequence of DNAI1 was screened (SSCP analysis and direct sequencing) in a group of PCD patients (157 families, 185 affected individuals), the first ever studied large cohort of PCD patients of Slavic origin (mostly Polish); multiplex ligation-dependent probe amplification (MLPA) analysis was performed in a subset of ~80 families.

Results

Three previously reported mutations (IVS1+2-3insT, L513P and A538T) and two novel missense substitutions (C388Y and G515S) were identified in 12 families (i.e. ~8% of non-related Polish PCD patients). The structure of background SNP haplotypes indicated common origin of each of the two most frequent mutations, IVS1+2-3insT and A538T. MLPA analysis did not reveal any significant differences between patients and control samples. The Polish cohort was compared with all the previously studied PCD groups (a total of 487 families): IVS1+2-3insT remained the most prevalent pathogenetic change in DNAI1 (54% of the mutations identified worldwide), and the increased global prevalence of A538T (14%) was due to the contribution of the Polish cohort.

Conclusions

The worldwide involvement of DNAI1 mutations in PCD pathogenesis in families not preselected for ODA defects ranges from 7 to 10%; this global estimate as well as the mutation profile differs in specific populations. Analysis of the background SNP haplotypes suggests that the increased frequency of chromosomes carrying A538T mutations in Polish patients may reflects local (Polish or Slavic) founder effect. Results of the MLPA analysis indicate that no large exonic deletions are involved in PCD pathogenesis.  相似文献   
50.
The antimicrobial activity of eight cationic, two neutral and three anionic liposome compositions containing meropenem and gentamicin was tested in vitro in broth and serum medium. The cationic formulations showed better antibacterial efficacy against both Gram-positive and Gram-negative bacteria than the anionic and neutral ones, regardless of the encapsulated drug. The most effective formulations were the cationic PC/DOPE/DOTAP 3:4:3 and PC/Chol/DOTAP 3:4:3, as the MICs with meropenem were 2 to 4 times lower than those of the free drug.  相似文献   
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