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1.
AbstractIn 1822, William Buckland first recognized Pleistocene vertebrate coprolites, and they are now known from more multiple localities with a global distribution. Carnivore coprolites dominate, and there are two distinct biogeographic and taphonomic provinces for vertebrate coprolites in the Pleistocene. The Castrocopros province of North and South America is characterized by a dominance of herbivore coprolites, which are preserved almost exclusively in caves. The Hyaenacoprus province in Africa, Europe and Asia is dominated by hyena coprolites that occur mainly in caves, but also in other depositional environments. Pacific Islands may represent a third province characterized by dominant bird coprolites from caves, but the known localities are all Holocene. Mammuthocopros allenorum ichnogen. and ichnosp. nov. is a coprolite of Mammuthus columbi from Utah, USA. 相似文献
2.
M.P. Sangorrín V. García C.A. Lopes J.S. Sáez C. Martínez M.A. Ganga 《Journal of applied microbiology》2013,114(4):1066-1074
Aims
Dekkera bruxellensis and Pichia guilliermondii are contaminating yeasts in wine due to the production of phenolic aromas. Although the degradation pathway of cinnamic acids, precursors of these phenolic compounds has been described in D. bruxellensis, no such pathway has been described in P. guilliermondii.Methods and Results
A molecular and physiological characterization of 14 D. bruxellensis and 15 P. guilliermondii phenol‐producing strains was carried out. Both p‐coumarate decarboxylase (CD) and vinyl reductase (VR) activities, responsible for the production of volatile phenols, were quantified and the production of 4‐vinylphenol and 4‐ethylphenol were measured. All D. bruxellensis and some P. guilliermondii strains showed the two enzymatic activities, whilst 11 of the 15 strains of this latter species showed only CD activity and did not produce 4‐EP in the assay conditions. Furthermore, PCR products obtained with degenerated primers showed a low homology with the sequence of the gene for a phenyl acrylic acid decarboxylase activity described in Saccharomyces cerevisiae.Conclusions
D. bruxellensis and P. guilliermondii may share a similar metabolic pathway for the degradation of cinnamic acids.Significance and Impact of the Study
This is the first work that analyses the CD and VR activities in P. guilliermondii, and the results suggest that within this species, there are differences in the metabolization of cinnamic acids. 相似文献3.
4.
A meta‐analysis of the association between Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum 下载免费PDF全文
Qin Xiang Ng Nandini Venkatanarayanan Michelle Lee Zhi Qing De Deyn Collin Yih Xian Ho Yin Mo Wee‐Song Yeo 《Helicobacter》2018,23(1)
Background
Hyperemesis gravidarum remains a common, distressing, and significant yet poorly understood disorder during pregnancy. The association between maternal Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum has been increasingly recognized and investigated. This study thus aimed to provide an updated review and meta‐analysis of the topic.Methods
Using the search terms (H. pyloriOR Helicobacter ORHelicobacter pyloriOR infection) AND (pregnancy OR emesis OR hyperemesis gravidarum OR nausea OR vomiting), a preliminary search on the PubMed, Ovid, Web of Science, Google Scholar, and WanFang database yielded 372 papers published in English between January 1st, 1960 and June 1st, 2017.Results
A total of 38 cross‐sectional and case‐control studies, with a total of 10 289 patients were eligible for review. Meta‐analysis revealed a significant association between H. pylori infection and hyperemesis gravidarum during pregnancy, with a pooled odds ratio of 1.348 (95% CI: 1.156‐1.539, P < .001). Subgroup analysis found that serologic and stool antigen tests were comparable methods of detecting H. pylori as they yielded similar odds ratios.Limitations
Although the studies did not have high heterogeneity (I2 = 28%), publication bias was observed, and interstudy discrepancies in the diagnostic criteria adopted for hyperemesis gravidarum limit the reliability of findings. Also, 15 of the included studies were from the same country (Turkey), which could limit the generalizability of current findings. The prevalence of H. pylori infection varies throughout the world, and there may also be pathogenic differences as most strains of H. pylori in East Asia carry the cytotoxin‐associated gene A gene.Conclusion
H. pylori infection was associated with an increased likelihood of hyperemesis gravidarum during pregnancy. Given the high prevalence of H. pylori infections worldwide, detecting H. pylori infection and the eradication of maternal H. pylori infection could be part of maternal hyperemesis gravidarum management. Further confirmation with robust longitudinal studies and mechanistic investigations are needed. 相似文献5.
Helicobacter Pylori infection of the gallbladder and the risk of chronic cholecystitis and cholelithiasis: A systematic review and meta‐analysis 下载免费PDF全文
Background
Helicobacter pylori is coexisted with various diseases, including chronic gastritis, ulcer, and gastric cancer. Besides, chronic cholecystitis and cholelithiasis are extremely widespread over the world, which are considered as high health‐care cost burdens of digestive diseases. Epidemiologic evidence on Helicobacter pylori infection in gallbladder increasing the risk of biliary diseases has been contradictory.Aim
Conduct a meta‐analysis of overall studies and investigate an association between Helicobacter pylori infection of the gallbladder with chronic cholecystitis/cholelithiasis.Methods
We used PubMed, EMBASE, and Cochrane library databases to identify all published studies before August 2017. Pooled odds ratios (OR) and corresponding 95% confidence intervals (CIs) were obtained using the random effects model. Heterogeneity, sensitivity, and stratified analyses were also performed.Results
Eighteen studies involving 1544 participants and 1061 biliary cases with chronic cholecystitis/cholelithiasis were included. Helicobacter pylori infection of the gallbladder was significantly associated with an increased risk of chronic cholecystitis and cholecystitis (OR = 3.022; 95% CI, 1.897‐4.815; I2 = 20.1%). In addition, country‐based subgroup analysis also showed a positive association between Helicobacter pylori positivity and chronic cholecystitis/cholelithiasis risk. The ORs (95% CIs) for Asian and non‐Asian region studies were 3.75 (1.83‐7.71) and 2.25 (1.29‐3.89), respectively.Conclusion
This meta‐analysis suggests that infection of the gallbladder with Helicobacter pylori is closely related to an increased risk of chronic cholecystitis and cholelithiasis. 相似文献6.
Para‐psychobiotic Lactobacillus gasseri CP2305 ameliorates stress‐related symptoms and sleep quality 下载免费PDF全文
Aims
To confirm the stress‐relieving effects of heat‐inactivated, enteric‐colonizing Lactobacillus gasseri CP2305 (paraprobiotic CP2305) in medical students taking a cadaver dissection course.Methods and Results
Healthy students (21 males and 11 females) took paraprobiotic CP2305 daily for 5 weeks during a cadaver dissection course. The General Health Questionnaire and the Pittsburgh Sleep Quality Index were employed to assess stress‐related somatic symptoms and sleep quality respectively. The aggravation of stress‐associated somatic symptoms was observed in female students (P = 0·029). Sleep quality was improved in the paraprobiotic CP2305 group (P = 0·038), particularly in men (P = 0·004). Among men, paraprobiotic CP2305 shortened sleep latency (P = 0·035) and increased sleep duration (P = 0·048). Diarrhoea‐like symptoms were also effectively controlled with CP2305 (P = 0·005) in men. Thus, we observed sex‐related differences in the effects of paraprobiotic CP2305. In addition, CP2305 affected the growth of faecal Bacteroides vulgatus and Dorea longicatena, which are involved in intestinal inflammation.Conclusions
CP2305 is a potential paraprobiotic that regulates stress responses, and its beneficial effects may depend on specific cell component(s).Significance and Impact of the Study
This study characterizes the effects of a stress‐relieving para‐psychobiotic in humans. 相似文献7.
Ian Towle Paul J. Constantino Matthew R. Borths Carolina Loch 《American journal of physical anthropology》2023,180(2):401-408
Objectives
Archaeolemur is a recently extinct genus of lemur that is often compared to some Cercopithecidae, especially baboons. This is due in part to their derived dentition, with large anterior teeth and reduced bilophodont molars. Research involving comparative morphology, analysis of coprolites, isotopes, and enamel structure, have suggested Archaeolemur had an omnivorous diet involving mechanically challenging items. Yet, microwear analysis of posterior teeth does not necessarily support this conclusion.Materials and Methods
In this macroscopic study, dental chipping was recorded on permanent teeth of Archaeolemur from different localities (53 individuals; 447 permanent teeth; including both A. edwardsi and A. majori specimens). This study aimed to compare chipping patterns across the dentition of Archaeolemur with chipping in other primates.Results
The results show enamel chipping was prevalent on the anterior teeth of Archaeolemur (38.9% of anterior teeth showed at least one fracture) yet rare in posterior teeth (9%). There was a decrease in chipping frequency across the dentition, moving distally from incisors (50%; 20/40), through caniniform teeth (30%; 15/50), premolars (9.5%; 16/169), and molars (8.5%; 16/188).Discussion
The results support previous research suggesting Archaeolemur had a varied omnivorous diet in which the anterior dentition was used for extensive food processing. This likely included mechanically challenging items such as tough/hard large fruits, small vertebrates, and crustaceans. Such a high rate of chipping in the anterior dentition is uncommon in other primates, with exception of hominins.8.
Y.‐H. Hsu S.R. Cook T.W. Alexander C.L. Klima Y.D. Niu L.B. Selinger T.A. McAllister 《Journal of applied microbiology》2013,114(6):1592-1603
Aims
This study aimed to characterize the impact of lytic and temperate bacteriophages on the genetic and phenotypic diversity of Mannheimia haemolytica from feedlot cattle.Methods and Results
Strictly lytic phages were not detected from bovine nasopharyngeal (n = 689) or water trough (n = 30) samples, but Myoviridae‐ or Siphoviridae‐like phages were induced from 54 of 72 M. haemolytica strains by mitomycin C, occasionally from the same strain. Phages with similar restriction fragment length polymorphism profiles (RFLP ≥70% relatedness) shared common host serotypes 1 or 2 (P < 0·000 1). Likewise, phages with similar RFLP tended to occur in genetically related host bacteria (70–79% similarity). Host range assays showed that seven phages from host serotypes 1, 2 and 6 lysed representative strains of serotypes 1, 2 or 8. The genome of vB_MhM_1152AP from serotype 6 was found to be collinear with P2‐like phage φMhaA1‐PHL101.Conclusions
Prophages are a significant component of the genome of M. haemolytica and contribute significantly to host diversity. Further characterization of the role of prophage in virulence and persistence of M. haemolytica in cattle could provide insight into approaches to control this potential respiratory pathogen.Significance and Impact of the Study
This study demonstrated that prophages are widespread within the genome of M. haemolytica isolates and emphasized the challenge of isolating lytic phage as a therapeutic against this pathogen. 相似文献9.
Background
Operation of natural selection can be characterized by a variety of quantities. Among them, variance of relative fitness V and load L are the most fundamental. 相似文献10.
Tao Dong Sarah M Chiang Charlie Joyce Rosemary Yu Herb E Schellhorn 《BMC microbiology》2009,9(1):118-13
Background
Though RpoS is important for survival of pathogenic Escherichia coli in natural environments, polymorphism in the rpoS gene is common. However, the causes of this polymorphism and consequential physiological effects on gene expression in pathogenic strains are not fully understood. 相似文献11.
X.Q. Mao Z. Zhang H. Jiang R.Y. Chai H.P. Qiu J.Y. Wang X.F. Du B. Li G.C. Sun 《Journal of applied microbiology》2013,114(5):1480-1490
Aim
To examine the inhibition effects of rhizosphere fungal strain MF‐91 on the rice blast pathogen Magnaporthe grisea and sheath blight pathogen Rhizoctonia solani.Methods and Results
Rhizosphere fungal strain MF‐91 and its metabolites suppressed the in vitro mycelial growth of R. solani. The inhibitory effect of the metabolites was affected by incubation temperature, lighting time, initial pH and incubation time of rhizosphere fungal strain MF‐91. The in vitro mycelial growth of M. grisea was insignificantly inhibited by rhizosphere fungal strain MF‐91 and its metabolites. The metabolites of rhizosphere fungal strain MF‐91 significantly inhibited the conidial germination and appressorium formation of M. grisea. Moreover, the metabolites reduced the disease index of rice sheath blight by 35·02% in a greenhouse and 57·81% in a field as well as reduced the disease index of rice blast by 66·07% in a field. Rhizosphere fungal strain MF‐91 was identified as Chaetomium aureum based on the morphological observation, the analysis of 18S ribosomal DNA internal transcribed spacer sequence and its physiological characteristics, such as the optimal medium, temperature and initial pH for mycelial growth and sporulation production.Conclusions
Rhizosphere fungus C. aureum is effective in the biocontrolling of rice blast pathogen M. grisea and sheath blight pathogen R. solani both in in vitro and in vivo conditions.Significance and Impact of the Study
This study is the first to show that rhizosphere fungus C. aureum is a potential fungicide against rice blast and sheath blight pathogens. 相似文献12.
Brittany E. Harlow Michael D. Flythe Glen E. Aiken 《Journal of applied microbiology》2018,124(1):58-66
Aims
The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity.Methods and Results
When bovine microbial rumen cell suspensions (n = 3) were incubated (24 h, 39°C) with ground hay, cellulolytic bacteria proliferated, short‐chain fatty acids were produced and pH declined. BCA (30 μg ml?1) had no effect on the number of cellulolytic bacteria or pH, but increased acetate, propionate and total SCFA production. Addition of BCA improved total digestibility when cell suspensions (n = 3) were incubated (48 h, 39°C) with ground hay, Avicel, or filter paper. Fibrobacter succinogenes S85, Ruminococcus flavefaciens 8 and Ruminococcus albus 8 were directly inhibited by BCA. Synergistic antimicrobial activity was observed with BCA and heat killed cultures of cellulolytic bacteria, but the effects were species dependent.Conclusions
These results indicate that BCA improves fibre degradation by influencing cellulolytic bacteria competition and guild composition.Significance and Impact of the Study
BCA could serve as a feed additive to improve cellulosis when cattle are consuming high‐fibre diets. Future research is needed to evaluate the effect of BCA on fibre degradation and utilization in vivo. 相似文献13.
Joyce Y Tung Mitchell P Rosen Lawrence M Nelson Paul J Turek John S Witte Daniel W Cramer Marcelle I Cedars Renee A Reijo-Pera 《Reproductive biology and endocrinology : RB&E》2006,4(1):40-6
Background
TheDeleted-in-AZoospermia-Like (DAZL) gene has homologs required for germ cell development in many organisms. Recently, we showed that there are several common polymorphisms within theDAZL gene that are associated with age at ovarian failure/menopause and sperm count. 相似文献14.
Mario Varcamonti Slavica Arsenijevic Luca Martirani Daniela Fusco Gino Naclerio Maurilio De Felice 《Microbial cell factories》2006,5(1):6-6
Background
Heat and cold shock response are normally considered as independent phenomena. A small amount of evidence suggests instead that interactions may exist between them in two Lactococcus strains. 相似文献15.
Victor M. Bravo-Cuevas Nuria M. Morales-García Christian R. Barrón-Ortiz Jessica M. Theodor M. A. Cabral-Perdomo 《Ichnos》2017,24(4):239-249
We present the first reported occurrence of canid coprolites from the late Pleistocene of central Mexico. The sample consists of five associated coprolites recovered from Quaternary deposits that crop out in southeastern Hidalgo, central Mexico. The material shows several of the typical features of canid feces, including elongated cylindrical shape, uncommon and nondistinct constrictions, and one tapered end. The coprolites are similar in size to feces of North American foxes, such as Vulpes macrotis, V. lagopus, V. vulpes, and Urocyon cinereoargenteus; likewise, their size might be comparable to those of the Pleistocene canid Canis cedazoensis. The content of the studied coprolites consists of numerous teeth and bone fragments referable to the pocket gophers Pappogeomys or Cratogeomys. The coprolite content is related to a mostly carnivorous diet comparable to that of C. cedazoensis, wolves (Canis lupus, C. rufus, and C. dirus), and some foxes (V. macrotis and V. velox). As a result, it is proposed that the potential trace maker of the coprolites could be a form similar to a carnivorous fox or a small dog. These trace fossils represent the first indirect evidence of canids in the late Pleistocene of Hidalgo and provide additional information regarding the geographic distribution of the Canidae in temperate areas of North America that now are part of central Mexico during the second half of the Pleistocene. 相似文献
16.
Application of NIR Spectroscopy Coupled with PLS Regression for Quantification of Total Polyphenol Contents from the Fruit and Aerial Parts of Citrullus colocynthis 下载免费PDF全文
Tania S. Rizvi Fazal Mabood Liaqat Ali Mohammed Al‐Broumi Hamida K.M. Al Rabani Javid Hussain Farah Jabeen Suryyia Manzoor Ahmed Al‐Harrasi 《Phytochemical analysis : PCA》2018,29(1):16-22
Introduction
Citrullus colocynthis (L.) Schrad is extensively used to treat diabetes, obesity, fever, cancer, amenorrhea, jaundice, leukemia, rheumatism, and respiratory diseases. Chemical studies have indicated the presence of several cucurbitacins, flavones, and other polyphenols in this plant. These phytochemical constituents are responsible for the interesting antioxidant and other biological activities of C. colocynthis.Objective
In the present study, for the first time, near infrared (NIR) spectroscopy coupled with partial least square (PLS) regression analysis was used to quantify the polyphenolic phytochemicals of C. colocynthis.Methodology
The fruit and aerial parts of the C. colocynthis were extracted individually in methanol followed by fractionation in n‐hexane, chloroform, ethyl acetate, n‐butanol, and water. Near infrared (NIR) spectra were obtained in absorption mode in the wavelength range 700–2500 nm. The PLS regression model was then built from the obtained spectral data to quantify the total polyphenol contents in the selected plant samples.Results
The PLS regression model obtained had a R2 value of 99% with a 0.98 correlationship value and a good prediction with a root mean square error of prediction (RMSEP) value of 1.89% and correlation of 0.98. These results were further confirmed through UV–vis spectroscopy and it is found that the ethyl acetate fraction has the maximum value for polyphenol contents (101.7 mg/100 g; NIR, 100.4 mg/100 g; UV–vis).Conclusions
The polyphenolic phytochemicals of the fruit and aerial parts of C. colocynthis have been quantified successfully by using multivariate analysis in a non‐destructive, economical, precise, and highly sensitive method, which uses very simple sample preparation. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献17.
Background
The Bacteroidetes and Chlorobi species constitute two main groups of the Bacteria that are closely related in phylogenetic trees. The Bacteroidetes species are widely distributed and include many important periodontal pathogens. In contrast, all Chlorobi are anoxygenic obligate photoautotrophs. Very few (or no) biochemical or molecular characteristics are known that are distinctive characteristics of these bacteria, or are commonly shared by them. 相似文献18.
Carvacrol and eugenol effectively inhibit Rhizopus stolonifer and control postharvest soft rot decay in peaches 总被引:1,自引:0,他引:1 下载免费PDF全文
Aims
This study aimed to investigate the antifungal mechanism of carvacrol and eugenol to inhibit Rhizopus stolonifer and the control of postharvest soft rot decay in peaches.Methods and Results
To investigate the antifungal mechanism, the effects of carvacrol and eugenol on the mycelium growth, leakages of cytoplasmic contents, mycelium morphology, cell membrane and membrane composition of R. stolonifer were studied. Carvacrol and eugenol both exhibited dose‐dependent antifungal activity against R. stolonifer, carvacrol at a concentration of 2 μl per plant and eugenol at a concentration of 4 μl per plant inhibited fungal growth completely. The two essential oils (EOs) increased cell membrane penetrability and caused the leakage of cytoplasm, nucleic acid and protein content. The observation using scanning electron microscopy and fluorescent microscopy showed modification of the hyphal morphology and breakage of the cell plasma membrane. Decreased ergosterol contents confirmed that the two EOs could destroy the membrane of R. stolonifer. For the in vivo test, the inhibition of soft rot disease and the induction of defence‐related enzymes were investigated. Carvacrol and eugenol significantly reduced the incidence and severity of soft rot decay in inoculated peaches. The best treatments for controlling soft rot decay were obtained at 0·5 μl l?1 for carvacrol and 1 μl l?1 for eugenol. The activities of defence‐related enzymes in peaches were also enhanced by fumigation with two EOs.Conclusion
This study showed that carvacrol and eugenol could effectively inhibit the growth of R. stolonifer in vitro and successfully control the incidence of soft rot decay in honey peaches.Significance and Impact of the Study
The above findings may be the main antifungal mechanism of carvacrol and eugenol on R. stolonifer. Furthermore, carvacrol and eugenol are helpful for their commercial application on the preservation of fresh fruit. 相似文献19.
Background
Interactions between Mycobacterium avium subsp. paratuberculosis (Map) and free-living protozoa in water are likely to occur in nature. The potential impact of ingestion of Map by two naturally occurring Acanthamoeba spp. on this pathogen's survival and chlorine resistance was investigated. 相似文献20.
N. Nayan A.S.M. Sonnenberg W.H. Hendriks J.W. Cone 《Journal of applied microbiology》2018,125(2):468-479