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91.
Vanessa O. Ezenwa Sarah A. Budischak Peter Buss Mauricio Seguel Gordon Luikart Anna E. Jolles Kaori Sakamoto 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(3)
Pathogen interactions arising during coinfection can exacerbate disease severity, for example when the immune response mounted against one pathogen negatively affects defense of another. It is also possible that host immune responses to a pathogen, shaped by historical evolutionary interactions between host and pathogen, may modify host immune defenses in ways that have repercussions for other pathogens. In this case, negative interactions between two pathogens could emerge even in the absence of concurrent infection. Parasitic worms and tuberculosis (TB) are involved in one of the most geographically extensive of pathogen interactions, and during coinfection worms can exacerbate TB disease outcomes. Here, we show that in a wild mammal natural resistance to worms affects bovine tuberculosis (BTB) severity independently of active worm infection. We found that worm-resistant individuals were more likely to die of BTB than were nonresistant individuals, and their disease progressed more quickly. Anthelmintic treatment moderated, but did not eliminate, the resistance effect, and the effects of resistance and treatment were opposite and additive, with untreated, resistant individuals experiencing the highest mortality. Furthermore, resistance and anthelmintic treatment had nonoverlapping effects on BTB pathology. The effects of resistance manifested in the lungs (the primary site of BTB infection), while the effects of treatment manifested almost entirely in the lymph nodes (the site of disseminated disease), suggesting that resistance and active worm infection affect BTB progression via distinct mechanisms. Our findings reveal that interactions between pathogens can occur as a consequence of processes arising on very different timescales.Interactions between pathogens cooccurring within a single host can have profound effects on infection outcomes, ranging from the severity of clinical disease in individual hosts to the rate of disease spread across populations (1–3). Because most hosts are commonly infected by more than one type of pathogen at a time (4), understanding the consequences of pathogen interactions during concurrent infection (or coinfection) is essential for effective disease management and control. While many studies focus on pathogen interactions that are the result of one pathogen responding to the simultaneous presence of another (5), two pathogens need not overlap in time to interact with one another. For example, heterologous immunity, where prior exposure or infection with one pathogen modifies the immune response to another, can drive both positive and negative interactions between pathogens (6). This phenomenon highlights how modifications of the host immune system by one pathogen that occur during the lifetime of a host (i.e., in ecological time) can shape future responses to secondary pathogens. Likewise, strong selection pressure imposed by pathogens on hosts, particularly on immune function (7), can result in modifications of the host immune system that occur over generations (i.e., in evolutionary time), a process which should also affect responses to secondary infections. In this case, a historical population-level response to selection by one pathogen may generate heritable differences among individuals in contemporary responses to another. Crucially, ecological- vs. evolutionary-scale interactions between pathogens may operate for different reasons, so distinguishing between the two is integral to understanding both the mechanistic basis and consequences of these interactions.Helminths, or parasitic worms, and tuberculosis (TB) are involved in one of the most geographically extensive of pathogen interactions (2, 8). Both pathogens affect approximately one-third of the world’s human population and are widespread in domestic and wild animals (9–11). Caused by bacteria in the Mycobacterium tuberculosis complex, including M. tuberculosis (Mtb), the causative agent of human TB, and Mycobacterium bovis (Mb), the causative agent of bovine TB, TB is responsible for 2 million human deaths (12) and 25% of all disease-related cattle deaths (13) annually. In humans, about 10% of individuals infected with Mtb progress to active pulmonary disease, but the mechanisms underlying progression to active TB are poorly defined (14). Accumulating evidence suggests that coinfection with worms may be a factor in TB disease progression (2, 15), although some studies do not support this link, highlighting the complex nature of worm–TB interactions (16). Interestingly, research in laboratory animals suggests that enhanced immunity (i.e., resistance) to worms can compromise a host’s ability to control TB even in the absence of active worm infection (17–20), implying that evolved defenses against worms may independently affect the response to TB. Considered in light of widespread worm resistance in human and animal populations (21, 22) and the broad geographic coincidence of worms and TB, worm–TB interactions may represent an illustrative case where variation in evolved resistance to one pathogen (worms) contributes to variable responses to another (TB).In this study, we tested the hypothesis that resistance to worms modifies the host response to TB. To do this, we monitored gastrointestinal (GI) worm (specifically strongyle nematode) and Mb infections in a cohort of wild African buffalo (Syncerus caffer) to assess the effects of natural variation in worm resistance on the incidence, severity, and progression of bovine TB (BTB). In previous work, we demonstrated the presence of an ecological interaction between worms and BTB in buffalo by showing that clearance of active worm infection via anthelmintic treatment reduces BTB-associated mortality (23). Thus, we took advantage of the fact that half of our study animals were subject to long-term deworming to compare the relative effects of worm coinfection vs. natural worm resistance on BTB outcomes. We found evidence of a genetic basis to worm resistance in buffalo and that buffalo with resistance to worms were more severely affected by BTB in terms of both mortality risk and disease progression. However, the mechanisms by which natural variation in the host response to worms was associated with BTB progression appeared to be distinct from the effects of anthelmintic treatment. Our results suggest that negative effects of worms on BTB outcomes occur as a result of both concurrent worm infection and genetically based differences in host responsiveness to worms. This discovery fundamentally alters our understanding of the timescales over which worms and TB interact in real-world populations. 相似文献
92.
David Vivas Inmaculada Roldán Raquel Ferrandis Francisco Marín Vanessa Roldán Antonio Tello-Montoliu Juan Miguel Ruiz-Nodar Juan José Gómez-Doblas Alfonso Martín Juan Vicente Llau María José Ramos-Gallo Rafael Muñoz Juan Ignacio Arcelus Francisco Leyva Fernando Alberca Raquel Oliva Ana María Gómez Carmen Montero Andrés Íñiguez 《Revista espa?ola de cardiología》2018,71(7):553-564
During the last few years, the number of patients receiving anticoagulant and antiplatelet therapy has increased worldwide. Since this is a chronic treatment, patients receiving it can be expected to need some kind of surgery or intervention during their lifetime that may require treatment discontinuation. The decision to withdraw antithrombotic therapy depends on the patient's thrombotic risk versus hemorrhagic risk. Assessment of both factors will show the precise management of anticoagulant and antiplatelet therapy in these scenarios. The aim of this consensus document, coordinated by the Cardiovascular Thrombosis Working Group of the Spanish Society of Cardiology, and endorsed by most of the Spanish scientific societies of clinical specialities that may play a role in the patient-health care process during the perioperative or periprocedural period, is to recommend some simple and practical guidelines with a view to homogenizing daily clinical practice.Full English text available from: www.revespcardiol.org/en 相似文献
93.
George E. A. Swann Virginia N. Panizzo Sebastiano Piccolroaz Vanessa Pashley Matthew S. A. Horstwood Sarah Roberts Elena Vologina Natalia Piotrowska Michael Sturm Andre Zhdanov Nikolay Granin Charlotte Norman Suzanne McGowan Anson W. Mackay 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(44):27211
Lake Baikal, lying in a rift zone in southeastern Siberia, is the world''s oldest, deepest, and most voluminous lake that began to form over 30 million years ago. Cited as the “most outstanding example of a freshwater ecosystem” and designated a World Heritage Site in 1996 due to its high level of endemicity, the lake and its ecosystem have become increasingly threatened by both climate change and anthropogenic disturbance. Here, we present a record of nutrient cycling in the lake, derived from the silicon isotope composition of diatoms, which dominate aquatic primary productivity. Using historical records from the region, we assess the extent to which natural and anthropogenic factors have altered biogeochemical cycling in the lake over the last 2,000 y. We show that rates of nutrient supply from deep waters to the photic zone have dramatically increased since the mid-19th century in response to changing wind dynamics, reduced ice cover, and their associated impact on limnological processes in the lake. With stressors linked to untreated sewage and catchment development also now impacting the near-shore region of Lake Baikal, the resilience of the lake’s highly endemic ecosystem to ongoing and future disturbance is increasingly uncertain.Ancient lakes have long been associated with both high levels of biodiversity and endemicity. However, they are also being threatened by anthropogenic forcings that have led to impacts ranging from the warming of lake waters (1), hydrological modifications (2), increases in aquatic toxicity (3), and declining endemic populations due to introductions of nonnative species (4). With global populations increasingly reliant on large and ancient lakes for ecosystem services, the biodiversity (5) and value of aquatic systems to society (6), particularly in ancient lake systems (7), are at risk. Lake Baikal (Russia) is an exceptional example of an ancient lake (Fig. 1). In addition to containing ∼20% of global surface freshwater, the lake is characterized by its high degree of biodiversity with over 2,500 flora and fauna, the majority of which are endemic (8). This has been attributed to the lake’s age and fully oxygenated water column, driven by seasonal overturning and deep water renewal (9, 10) that sustains an almost completely endemic deep water fauna (8).Open in a separate windowFig. 1.Location of Lake Baikal and its catchment (gray) together with the location of World Meteorological Organization station in Irkutsk, major catchment rivers (brown), coring sites (BAIK13-1, BAIK13-4), and sites providing additional data used in this study (BAIK13-7).Concerns exist over the future health of this unique ecosystem, amid evidence of extensive shoreline eutrophication (11, 12) and climate-induced shifts in primary productivity (13, 14). Together, these changes have impacted organisms ranging from sponges and gastropods to ciliates, flagellates, and algal communities (15). Given the likelihood of future anthropogenic disturbance on Lake Baikal, further disrupting productivity exchanges through the lake’s food web, there is a need to place these contemporary observations into their historical setting. In Lake Baikal, we have evidence that algal communities have undergone rapid multidecadal to multicentennial timescale changes over the last 2,000 y (16). However, there is a need to also gain a clearer insight into how biogeochemical and nutrient cycling has altered over the same timescale, both to contextualize natural and anthropogenic drivers of change and to understand the susceptibility of the lake’s ecosystem to further alteration under different climate states (17). Annual primary productivity in Lake Baikal is ultimately regulated by photic zone nutrient availability, in addition to ice/snow cover, which regulates light availability for photosynthesis (10, 18). Here, by analyzing the silicon isotope composition of diatom silica (δ30Sidiatom), we show that nutrient supply to the surface waters of Lake Baikal has rapidly increased through the 20th and 21st centuries coincident with increased wind-driven Ekman transport and reduced ice cover. These changes in photic zone nutrient availability have the potential to alter resource competition and prey–predator interactions across the lake (15, 19). 相似文献
94.
Head and neck squamous cell carcinoma lymphatic spread and survival: Relevance of vascular endothelial growth factor family for tumor evaluation 下载免费PDF全文
95.
Sarah Maheux-Lacroix Madeleine Lemyre Vanessa Couture Gabrielle Bernier Philippe Y. Laberge 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2015,19(1)
Methods:We report a prospective, consecutive case series of 128 outpatient TLHs performed for benign gynecologic conditions in a tertiary care center.Results:Of the 295 women scheduled for a TLH, 151 (51%) were attempted as an outpatient procedure. A total of 128 women (85%) were actually discharged home the day of their surgery. The most common reasons for admission the same day were urinary retention (19%) and nausea (15%). Indications for hysterectomy were mainly leiomyomas (62%), menorrhagia (24%), and pelvic pain (9%). Endometriosis and adhesions were found in 23% and 25% of the cases, respectively. Mean estimated blood loss was 56 mL and mean uterus weight was 215 g, with the heaviest uterus weighing 841 g. Unplanned consultation and readmission were infrequent, occurring in 3.1% and 0.8% of cases, respectively, in the first 72 hours. At 3 months, unplanned consultation, complication, and readmission had occurred in a similar proportion of inpatient and outpatient TLHs (17.2%, 12.5%, and 4.7% versus 18.1%, 12.7%, and 5.4%, respectively). In a logistic regression model, uterus weight, presence of adhesions or endometriosis, and duration of the operation were not associated with adverse outcomes.Conclusion:Same-day discharge is a feasible and safe option for carefully selected patients who undergo an uncomplicated TLH, even in the presence of leiomyomas, severe adhesions, or endometriosis. 相似文献
96.
97.
Leah Gandee Jer-Tsong Hsieh Vanessa Sperandio Cristiano G. Moreira Chih-Ho Lai Philippe E. Zimmern 《International braz j urol : official journal of the Brazilian Society of Urology》2015,41(1):67-77
Purpose
The treatment of urinary tract infections (UTI) with antibiotics is commonly used, but recurrence and antibiotic resistance have been growing and concerning clinicians. We studied whether the rapid onset of a protective biofilm may be responsible for the lack of effectiveness of antibiotics against selected bacteria.Materials and Methods
Two established uropathogenic Escherichia coli strains, UTI89 and CFT073, and two Pseudomonas aeruginosa strains, PA01 and Boston-41501, were studied to establish a reliable biofilm formation process. Bacterial growth (BG) was determined by optical density at 600 nm (OD 600) using a spectrophotometer, while biofilm formation (BF) using crystal violet staining was measured at OD 550. Next, these bacterial strains were treated with clinically relevant antibiotics, ciprofloxacin HCl (200 ng/mL and 2 μg/mL), nitrofurantoin (20 μg/mL and 40 μg/mL) and ampicillin (50 μg/mL) at time points of 0 (T0) or after 6 hours of culture (T6). All measurements, including controls (bacteria -1% DMSO), were done in triplicates and repeated three times for consistency.Results
The tested antibiotics effectively inhibited both BG and BF when administered at T0 for UPEC strains, but not when the antibiotic administration started 6 hours later. For Pseudomonas strains, only Ciprofloxacin was able to significantly inhibit bacterial growth at T0 but only at the higher concentration of 2 μg/mL for T6.Conclusion
When established UPEC and Pseudomonas bacteria were allowed to culture for 6 hours before initialization of treatment, the therapeutic effect of selected antibiotics was greatly suppressed when compared to immediate treatment, probably as a result of the protective nature of the biofilm. 相似文献98.
Kellen C. Tjioe Heliton G. de Lima Lester D. R. Thompson Vanessa S. Lara José H. Damante Christiano de Oliveira-Santos 《Head and neck pathology》2015,9(3):354-359
Papillary cystadenoma is a rare, benign salivary gland tumor which is well-circumscribed, containing cystic cavities with intraluminal papillary projections. Only 19 cases arising within minor salivary glands (MnSG) from the oral cavity sites have been reported in the English literature (PubMed 1958–2014). We report 11 new cases of MnSG papillary cystadenomas in conjunction with a review of the literature. Demographic information, clinical and histologic features, treatment and prognosis are compiled and discussed for all 30 cases reported in the English literature. 相似文献
99.
Rhu-Epo down-regulates pro-tumorigenic activity of cancer-associated fibroblasts in multiple myeloma
Vanessa?Desantis Maria?Antonia?Frassanito Roberto?Tamma Ilaria?Saltarella Lucia?Di?Marzo Aurelia?Lamanuzzi Antonio?Giovanni?Solimando Simona?Ruggieri Tiziana?Annese Beatrice?Nico Angelo?Vacca Domenico?RibattiEmail authorView authors OrcID profile 《Annals of hematology》2018,97(7):1251-1258
We have previously demonstrated that recombinant human erythropoietin (rHuEpo) is involved in the regulation of the angiogenic response in multiple myeloma (MM) through a direct effect on macrophages and endothelial cells isolated from the bone marrow of patients with MM. The aim of the present study was designed to determine the effects of rHuEpo on cancer-associated fibroblasts (CAFs) from monoclonal gammopathy of undetermined significance (MGUS) and MM patients by means of in vitro and in vivo assays. rHuEpo treatment reduces the expression of mRNA levels of fibroblast activation markers, namely alpha smooth actin (αSMA) and fibroblast activation protein (FAP) in MGUS and MM CAFs, and of pro-inflammatory and pro-angiogenic cytokines, including interleukin (IL)-6 and IL-8, vascular endothelial growth factor-A (VEGF-A), fibroblast growth factor-2 (FGF-2), and hepatocyte growth factor (HGF) in MM CAFs. Moreover, rHuEpo inhibits the proliferative activity of MM CAFs and increased the apoptosis of MGUS and MM CAFs. Overall, these data suggest that rHu-Epo down-regulates CAFs pro-tumorigenic activity. Moreover, these results are not suggestive for a pro-angiogenic activity of rHuEpo on CAFs. In fact, rHuEpo pre-treatment induces a low angiogenic response in vivo in the chorioallantoic membrane (CAM) assay of MGUS and MM CAFs conditioned medium, not comparable to that of a well-known angiogenic cytokine, VEGF-A, tested in the same assay. 相似文献
100.