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1.
BMC Genomics ; 23(1): 709, 2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36258177

RESUMEN

BACKGROUND: The extent and impact of evolutionary change occurring in natural populations in response to rapid anthropogenic impact is still poorly understood on the genome-wide level. Here, we explore the genetic structure, demographic history, population differentiation, and domestic introgression based on whole genome data of the endangered European wildcat in Germany, to assess potential genomic consequences of the species' recent spread across human-dominated cultural landscapes. RESULTS: Reconstruction of demographic history and introgression rates based on 47 wildcat and 37 domestic cat genomes suggested late introgression between wild and domestic cat, coinciding with the introduction of domestic cat during the Roman period, but overall relatively low rates of hybridization and introgression from domestic cats. Main population divergence found between an eastern and central German wildcat clade was found to be of rather recent origin (200 y), and thus the likely consequence of anthropogenic persecution and resulting isolation in population refugia. We found similar effective population sizes and no substantial inbreeding across populations. Interestingly, highly differentiated genes between wild cat populations involved in the tryptophan-kynurenine-serotonin pathway were revealed, which plays a role in behavioral processes such as stress susceptibility and tolerance, suggesting that differential selection acted in the populations. CONCLUSIONS: We found strong evidence for substantial recent anthropogenic impact on the genetic structure of European wildcats, including recent persecution-driven population divergence, as well as potential adaptation to human-dominate environments. In contrast, the relatively low levels of domestic introgression and inbreeding found in this study indicate a substantial level of "resistance" of this elusive species towards major anthropogenic impacts, such as the omnipresence of domestic cats as well as substantial habitat fragmentation. While those findings have strong implications for ongoing conservation strategies, we demand closer inspection of selective pressures acting on this and other wildlife species in anthropogenic environments.


Asunto(s)
ADN Mitocondrial , Triptófano , Gatos/genética , Humanos , Animales , ADN Mitocondrial/genética , Quinurenina , Serotonina , Efectos Antropogénicos
2.
Ann Hematol ; 101(6): 1311-1319, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35364726

RESUMEN

Reduced intensity conditioning (RIC) and reduced toxicity conditioning (RTC) regimens enable allogeneic hematopoietic stem cell transplantation (alloSCT) to more patients due to reduction in transplant-related mortality (TRM). The conditioning regimens with fludarabine and treosulfan (Flu/Treo) or fludarabine, amsacrine, cytarabine (FLAMSA)-RIC have shown their efficacy and tolerability in various malignancies. So far, no prospective study comparing the two regimens is available. Two studies compared the regimens retrospectively, in which both provided similar outcome. In this retrospective, single-center analysis, these two regimens were compared with regard to outcome, rate of acute and chronic graft versus host disease (GvHD), and engraftment. 113 consecutive patients with myeloid malignancies who received Flu/Treo or FLAMSA-RIC conditioning prior to alloSCT between 2007 and 2019 were included. Except for age, previous therapies, and remission status before alloSCT, patient characteristics were well balanced. The median follow-up time within this analysis was 44 months. There was no significant difference in absolute neutrophil count (ANC) or platelet engraftment between the two conditioning regimens. Overall survival (OS), the relapse-free survival (RFS), and the TRM were not significantly different between the two cohorts. The rate of GvHD did not differ between the two groups. In summary, this retrospective analysis shows that there is no major difference regarding tolerability and survival between the Flu/Treo and FLAMSA-RIC regimens. Despite several limitations due to uneven distribution concerning age and remission status, we demonstrate that Flu/Treo and FLAMSA-RIC provide similar outcomes and are feasible in older and intensively pre-treated patients.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Trastornos Mieloproliferativos , Anciano , Busulfano/análogos & derivados , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Acondicionamiento Pretrasplante , Vidarabina/análogos & derivados
4.
J Foot Ankle Surg ; 57(5): 1010-1013, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29655648

RESUMEN

Managing infections of the first metatarsophalangeal joint can be demanding because many patients present with late-stage infection and partial or total amputation of the first ray or the phalanx could be necessary. We describe such a patient who was successfully treated with a calcium-based resorbable bone substitute that preserved the first metatarsophalangeal joint. A 38-year-old female presented to our department with a foot infection. Examination revealed a methicillin-susceptible Staphylococcus aureus infection of the first metatarsophalangeal joint. The histopathologic findings confirmed active osteomyelitis of the first metatarsal head. The metatarsophalangeal joint was debrided with open synovectomy, the metatarsal head was curetted, and the bone defect was filled with 2 mL of a synthetic bone graft substitute. Two years later, she reported no problems with function or pain, the joint had full range of motion, and she had no local or systemic signs of infection. The most recent radiographs revealed no damage to the first metatarsophalangeal joint. A synthetic bone graft substitute can be a good alternative for treating forefoot infections when the soft tissues are intact and the bone defect is not so large that partial or full amputation is necessary.


Asunto(s)
Sustitutos de Huesos/uso terapéutico , Huesos Metatarsianos , Osteomielitis/diagnóstico , Osteomielitis/cirugía , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/cirugía , Adulto , Femenino , Humanos , Articulación Metatarsofalángica , Staphylococcus aureus
5.
J Cutan Pathol ; 43(8): 711-6, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27106295

RESUMEN

Painful subungual tumor masses in the toes usually emerge as glomus tumors or subungual exostoses. We present a patient with an aneurysmal bone cyst located subungually in whom the diagnosis was delayed due to inadequate diagnostic procedures, which led to marked destruction of the distal phalanx of the great toe of the right foot. After biopsy, the distal phalanx could not be preserved due to critical soft tissue involvement and the size of the process. Thus, we describe this rare entity to encourage clinicians to establish the diagnosis by biopsy of a tissue swelling of unclear origin and duration that does not resolve after a short time. Imaging examinations are useful in demonstrating periosteal involvement and extension of the lesion and can be helpful in the diagnostic algorithm. An interdisciplinary approach is a top priority to ensure optimal treatment.


Asunto(s)
Quistes Óseos Aneurismáticos/patología , Enfermedades de la Uña/patología , Adulto , Humanos , Masculino , Dedos del Pie/patología
6.
Arch Orthop Trauma Surg ; 136(7): 899-906, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27098293

RESUMEN

INTRODUCTION: The ideal treatment of the destructive septic arthritis of the hip joint remains controversial. The aim of the present retrospective study was to report on our experience about the use of antibiotic-loaded cement spacers in the treatment of destructive bacterial coxitis. MATERIALS AND METHODS: 22 consecutive patients (11 male, 11 female, mean age 59.7 years) have been treated with a two-stage protocol and implantation of an antibiotic-loaded cement spacer. All patients' records have been retrospectively evaluated with regard to comorbidities/predisposing factors, infection cause, causative pathogen organism, presence of a psoas abscess, surgical time of spacer implantation, duration of spacer implantation, spacer articulation, impregnation of bone cement, systemic antibiotic therapy, surgical time of prosthesis implantation, implant type, complications, and infection control rate. RESULTS: The most common identified organism was Staphylococcus aureus (73 %). The mean duration of spacer implantation was 88 days. Spacer-specific complications were observed in 23 % of the cases and spacer non-specific ones in 50 % between stages. The mortality rate after the first stage was 18 %. Prosthesis implantation was performed in 16 cases. At a mean follow-up of 44.8 (12-120) months, the primary infection control rate (after one spacer implantation) was 87 % (13/15) and the secondary infection control rate (after two spacer implantations) 100 %. CONCLUSIONS: Two-stage treatment and spacer implantation is associated with a high rate of infection control but also with a high mortality rate between stages.


Asunto(s)
Antibacterianos/uso terapéutico , Artritis Infecciosa/cirugía , Cementos para Huesos/uso terapéutico , Articulación de la Cadera/cirugía , Procedimientos Ortopédicos/métodos , Adulto , Anciano , Artritis Infecciosa/complicaciones , Artritis Infecciosa/mortalidad , Femenino , Estudios de Seguimiento , Articulación de la Cadera/microbiología , Humanos , Prótesis Articulares/efectos adversos , Masculino , Persona de Mediana Edad , Procedimientos Ortopédicos/efectos adversos , Procedimientos Ortopédicos/mortalidad , Infecciones Relacionadas con Prótesis/cirugía , Estudios Retrospectivos , Infecciones Estafilocócicas/complicaciones , Infecciones Estafilocócicas/cirugía , Staphylococcus aureus
7.
J Immunol ; 188(8): 3594-602, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22403439

RESUMEN

The proinflammatory cysteine protease caspase-1 is autocatalytically activated upon cytosolic sensing of a variety of pathogen-associated molecular patterns by Nod-like receptors. Active caspase-1 processes pro-IL-1ß and pro-IL-18 to generate the bioactive cytokines and to initiate pathogen-specific immune responses. Little information is available on caspase-1 and inflammasome activation during infection with the gastric bacterial pathogen Helicobacter pylori. In this study, we addressed a possible role for caspase-1 and its cytokine substrates in the spontaneous and vaccine-induced control of Helicobacter infection, as well as the development of gastritis and gastric cancer precursor lesions, using a variety of experimental infection, vaccine-induced protection, and gastric disease models. We show that caspase-1 is activated and IL-1ß and IL-18 are processed in vitro and in vivo as a consequence of Helicobacter infection. Caspase-1 activation and IL-1 signaling are absolutely required for the efficient control of Helicobacter infection in vaccinated mice. IL-1R(-/-) mice fail to develop protective immunity but are protected against Helicobacter-associated gastritis and gastric preneoplasia as a result of their inability to generate Helicobacter-specific Th1 and Th17 responses. In contrast, IL-18 is dispensable for vaccine-induced protective immunity but essential for preventing excessive T cell-driven immunopathology. IL-18(-/-) animals develop strongly accelerated pathology that is accompanied by unrestricted Th17 responses. In conclusion, we show in this study that the processing and release of a regulatory caspase-1 substrate, IL-18, counteracts the proinflammatory activities of another caspase-1 substrate, IL-1ß, thereby balancing control of the infection with the prevention of excessive gastric immunopathology.


Asunto(s)
Caspasa 1/inmunología , Gastritis/inmunología , Infecciones por Helicobacter/inmunología , Neoplasias Gástricas/prevención & control , Inmunidad Adaptativa/efectos de los fármacos , Animales , Vacunas Bacterianas , Caspasa 1/genética , Modelos Animales de Enfermedad , Gastritis/etiología , Gastritis/prevención & control , Regulación de la Expresión Génica , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/microbiología , Helicobacter pylori/inmunología , Interleucina-18/genética , Interleucina-18/inmunología , Interleucina-1beta/deficiencia , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Interleucina-1/deficiencia , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/inmunología , Transducción de Señal , Estómago/inmunología , Estómago/microbiología , Estómago/patología , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/microbiología , Células TH1/inmunología , Células Th17/inmunología , Vacunación
8.
Swiss Med Wkly ; 154: 3706, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38642339

RESUMEN

AIM OF THE STUDY: The COVID-19 pandemic has drawn attention to the benefit of wastewater-based epidemiology, particularly when case numbers are underreported. Underreporting may be an issue with mpox, where biological reasons and stigma may prevent patients from getting tested. Therefore, we aimed to assess the validity of wastewater surveillance for monitoring mpox virus DNA in wastewater of a Central European city and its association with official case numbers. METHODS: Wastewater samples were collected between 1 July and 28 August 2022 in the catchment area of Basel, Switzerland, and the number of mpox virus genome copies they contained was determined by real-time quantitative PCR. Logistic regression analyses were used to determine the odds of detectability of mpox virus DNA in wastewater, categorised as detectable or undetectable. Mann-Whitney U tests were used to determine associations between samples that tested positive for the mpox virus and officially reported cases and patients' recorded symptomatic phases. RESULTS: Mpox virus DNA was detected in 15 of 39 wastewater samples. The number of positive wastewater samples was associated with the number of symptomatic cases (odds ratio [OR] = 2.18, 95% confidence interval (CI) = 1.38-3.43, p = 0.001). The number of symptomatic cases differed significantly between days with positive versus negative wastewater results (median = 11 and 8, respectively, p = 0.0024). CONCLUSION: Mpox virus DNA was detectable in wastewater, even when officially reported case numbers were low (0-3 newly reported mpox cases corresponding to 6-12 symptomatic patients). Detectability in wastewater was significantly associated with the number of symptomatic patients within the catchment area. These findings illustrate the value of wastewater-based surveillance systems when assessing the prevalence of emerging and circulating infectious diseases.


Asunto(s)
Mpox , Aguas Residuales , Humanos , Monkeypox virus , Suiza/epidemiología , Pandemias , Monitoreo Epidemiológico Basado en Aguas Residuales , ADN
9.
Swiss Med Wkly ; 154: 3503, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38579316

RESUMEN

INTRODUCTION: Influenza infections are challenging to monitor at the population level due to many mild and asymptomatic cases and similar symptoms to other common circulating respiratory diseases, including COVID-19. Methods for tracking cases outside of typical reporting infrastructure could improve monitoring of influenza transmission dynamics. Influenza shedding into wastewater represents a promising source of information where quantification is unbiased by testing or treatment-seeking behaviours. METHODS: We quantified influenza A and B virus loads from influent at Switzerland's three largest wastewater treatment plants, serving about 14% of the Swiss population (1.2 million individuals). We estimated trends in infection incidence and the effective reproductive number (Re) in these catchments during a 2021/22 epidemic and compared our estimates to typical influenza surveillance data. RESULTS: Wastewater data captured the same overall trends in infection incidence as laboratory-confirmed case data at the catchment level. However, the wastewater data were more sensitive in capturing a transient peak in incidence in December 2021 than the case data. The Re estimated from the wastewater data was roughly at or below the epidemic threshold of 1 during work-from-home measures in December 2021 but increased to at or above the epidemic threshold in two of the three catchments after the relaxation of these measures. The third catchment yielded qualitatively the same results but with wider confidence intervals. The confirmed case data at the catchment level yielded comparatively less precise R_e estimates before and during the work-from-home period, with confidence intervals that included one before and during the work-from-home period. DISCUSSION: Overall, we show that influenza RNA in wastewater can help monitor nationwide influenza transmission dynamics. Based on this research, we developed an online dashboard for ongoing wastewater-based influenza surveillance in Switzerland.


Asunto(s)
COVID-19 , Gripe Humana , Humanos , Gripe Humana/epidemiología , Suiza/epidemiología , Aguas Residuales , ARN
10.
Anticancer Res ; 42(11): 5431-5441, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36288861

RESUMEN

BACKGROUND/AIM: Cytomegalovirus (CMV) reactivation is one of the most clinically significant complications in allogeneic stem cell recipients and a frequent cause for transplantation related mortality. Letermovir is a newly available and recently approved drug for CMV prophylaxis. In a retrospective single center analysis, we investigated the benefit of letermovir as CMV prophylaxis in allogeneic stem cell recipients. PATIENTS AND METHODS: We included 48 CMV-seropositive transplant recipients from January 2017 to August 2020 from our department. We compared the rate of CMV reactivation in patients who received letermovir as prophylaxis from day 0 after allogeneic stem cell transplantation (alloSCT) with a control group that did not receive CMV prophylaxis. The primary endpoint was CMV reactivation and was defined as an increase of CMV copies over 1250 Ul/ml in the peripheral blood; secondary endpoints were overall survival (OS) up to 180 days, engraftment and all-cause mortality. RESULTS: We included 21 patients in the control group and 27 patients in the letermovir group. Letermovir treatment led to a significantly reduced incidence of CMV reactivation after alloSCT (33.3% in the letermovir group versus 76.2% in the control group, p<0.001). The OS at day 180 was 80.9% in the control group versus 92.6% in the letermovir group (p<0.05). The median duration of letermovir prophylaxis was 192±104 days. CONCLUSION: Our results indicate that letermovir prophylaxis is associated with a significant lower risk of CMV reactivation and improved overall survival in CMV-seropositive stem cell recipients. Moreover, a prolonged use of letermovir prophylaxis might be a survival benefit.


Asunto(s)
Infecciones por Citomegalovirus , Trasplante de Células Madre Hematopoyéticas , Humanos , Citomegalovirus , Infecciones por Citomegalovirus/etiología , Infecciones por Citomegalovirus/prevención & control , Infecciones por Citomegalovirus/tratamiento farmacológico , Estudios Retrospectivos , Antivirales/uso terapéutico , Acetatos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos
11.
Biology (Basel) ; 11(12)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36552246

RESUMEN

Capillary endothelial cells modulate myocardial growth and function during pathological stress, but it is unknown how and whether this contributes to the development of heart failure. We found that the endothelial cell transcription factor GATA2 is downregulated in human failing myocardium. Endothelial GATA2 knock-out (G2-EC-KO) mice develop heart failure and defective myocardial signal transduction during pressure overload, indicating that the GATA2 downregulation is maladaptive. Heart failure and perturbed signaling in G2-EC-KO mice could be induced by strong upregulation of two unknown, endothelial cell-derived long non-coding (lnc) RNAs (AK037972, AK038629, termed here GADLOR1 and 2). Mechanistically, the GADLOR1/2 lncRNAs transfer from endothelial cells to cardiomyocytes, where they block stress-induced signalling. Thereby, lncRNAs can contribute to disease as paracrine effectors of signal transduction and therefore might serve as therapeutic targets in the future.

12.
Chemistry ; 17(27): 7560-8, 2011 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-21590820

RESUMEN

The results of the investigation of MGa(2) with M = Ca, Sr, Ba and of MGa(4) with M = Na, Ca, Sr, Ba by a combined application of NMR spectroscopy and quantum mechanical calculations are comprehensively evaluated. The electric-field gradient (EFG) was identified as the most reliable measure to study intermetallic compounds, since it is accessible with high precision by quantum mechanical calculations and, for nuclear spin I>1/2, by NMR spectroscopy. The EFG values obtained by NMR spectroscopy and quantum mechanical calculations agree very well for both series of investigated compounds. A deconvolution of the calculated EFGs into their contributions reveals its sensitivity to the local environment of the atoms. The EFGs of the investigated di- and tetragallides are dominated by the population of the p(x)-, p(y)-, and p(z)-like states of the Ga atoms. A general combined approach for the investigation of disordered intermetallic compounds by application of diffraction methods, NMR spectroscopy, and quantum mechanical calculations is suggested. This scheme can also be applied to other classes of crystalline disordered inorganic materials.

13.
Swiss Med Wkly ; 150: w20271, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32365217

RESUMEN

The reproductive number in Switzerland was between 1.5 and 2 during the first third of March, and has consistently decreased to around 1. After the announcement of the latest strict measure on 20 March 2020, namely that gatherings of more than five people in public spaces are prohibited, the reproductive number dropped significantly below 1; the authors of this study estimate the reproductive number to be between 0.6 and 0.8 in the first third of April.


Asunto(s)
Número Básico de Reproducción , Infecciones por Coronavirus/epidemiología , Epidemias , Neumonía Viral/epidemiología , COVID-19 , Humanos , Pandemias , Suiza/epidemiología
14.
Chemistry ; 15(7): 1673-84, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19123208

RESUMEN

Combined application of (69,71)Ga NMR spectroscopy and quantum mechanical calculations reveals the chemical bonding in the digallides of Ca, Sr, and Ba. An analysis of the electron localization function (ELF) shows honeycomb-like 6(3) nets of the Ga atoms as the most prominent structural features in SrGa(2) and BaGa(2). For CaGa(2) a description of a 3+1-coordinated Ga atom is revealed by the ELF and by an analysis of interatomic distances. The NMR spectroscopic signal shift is mainly due to the Knight shift and is almost equal for the investigated digallides, whereas the anisotropy of the signal shift decreases with the radius of the alkaline-earth metals. Calculated and observed values of the electric field gradient (EFG) are in good agreement for CaGa(2) and BaGa(2) but differ by about 21 % for SrGa(2) indicating structural instability. Better agreement is achieved by considering a puckering of the Ga layers. For BaGa(2) an instability of the structure is indicated by a peak in the density of states at the Fermi level, which is shifted to lower energies when taking puckering of the Ga layers into account. Both structural modifications are confirmed by crystallographic information. The Fermi velocity of the electrons is strongly anisotropic and is largest in the (001) plane of the crystal structure. This results in an alignment of the crystallites with the [001] axis perpendicular to the magnetic field as observed in (69,71)Ga NMR spectroscopy and magnetic susceptibility experiments. The electron transport is predominantly mediated by the Ga-Ga p(x)- and p(y)-like electrons in the (001) plane. The specific heat capacity of BaGa(2) was determined and indicated the absence of phase transitions between 1.8 and 320 K.

15.
Case Rep Orthop ; 2017: 2429459, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29430315

RESUMEN

Modular knee megaendoprotheses are commonly used devices for distal femur or proximal tibia replacement in tumor surgery as well as for treatment of some periprosthetic fractures around a loose or failed total knee arthroplasty. Structural failures of the prosthesis are well-known postoperative complications and have been reported for various prosthesis types. In the majority of the cases, the polyethylene parts fail. We would like to present an unusual case of a broken femoral component of an MRH® endoprosthesis four years after implantation.

16.
Eur J Cell Biol ; 85(9-10): 1079-90, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16782229

RESUMEN

Tandem affinity purification (TAP) is a method originally established in yeast to isolate highly purified protein complexes in a very gentle and efficient way. In this work, we have modified TAP for Dictyostelium applications and have proved it as a useful method to specifically isolate and identify microtubule-associated protein (MAP) complexes. MAPs are known to interact with other proteins to fulfill their complex functions in balancing the dynamic instability of microtubules as well as anchoring microtubules at the cell cortex, controlling mitosis at the centrosome and guiding transport along them. DdEB1 and the Dictyostelium member of the XMAP215 protein family, DdCP224, are known to be part of complexes at the microtubule tips as well as at the centrosome. Employing TAP and mass spectrometry we were able to prove an interaction between EB1 and the DdCP224. Additionally, among other interactions that remain to be confirmed by other methods, an interaction between DdCP224 and a TACC-family protein could be shown for the first time in Dictyostelium and was confirmed by colocalization and co-immunoprecipitation analyses.


Asunto(s)
Cromatografía de Afinidad/métodos , Dictyostelium/química , Proteínas Asociadas a Microtúbulos/aislamiento & purificación , Proteínas Protozoarias/aislamiento & purificación , Animales , Dictyostelium/metabolismo , Humanos , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Datos de Secuencia Molecular , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
17.
Ecol Evol ; 6(15): 5321-32, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27551385

RESUMEN

Endemic species on islands are highly susceptible to local extinction, in particular if they are exposed to invasive species. Invasive predators, such as feral cats, have been introduced to islands around the world, causing major losses in local biodiversity. In order to control and manage invasive species successfully, information about source populations and level of gene flow is essential. Here, we investigate the origin of feral cats of Hawaiian and Australian islands to verify their European ancestry and a potential pattern of isolation by distance. We analyzed the genetic structure and diversity of feral cats from eleven islands as well as samples from Malaysia and Europe using mitochondrial DNA (ND5 and ND6 regions) and microsatellite DNA data. Our results suggest an overall European origin of Hawaiian cats with no pattern of isolation by distance between Australian, Malaysian, and Hawaiian populations. Instead, we found low levels of genetic differentiation between samples from Tasman Island, Lana'i, Kaho'olawe, Cocos (Keeling) Island, and Asia. As these populations are separated by up to 10,000 kilometers, we assume an extensive passive dispersal event along global maritime trade routes in the beginning of the 19th century, connecting Australian, Asian, and Hawaiian islands. Thus, islands populations, which are characterized by low levels of current gene flow, represent valuable sources of information on historical, human-mediated global dispersal patterns of feral cats.

18.
Gut Microbes ; 6(6): 382-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26727421

RESUMEN

The Gram-negative bacterium Helicobacter pylori is both a normal constituent of the human gastric microbiota as well as a pathogen tightly associated with severe gastric disorders. The ability of H. pylori to activate the inflammasome and caspase-1 in antigen-presenting and other cells, and the resulting processing and release of caspase-1-dependent cytokines, impacts both the immunomodulatory and pathogenic activities of H. pylori. This article summarizes recent insights by us and others on the bacterial and host prerequisites of inflammasome activation. H. pylori predominantly activates the NLRP3 inflammasome through a process that requires TLR2-dependent licensing. We identified the urease enzyme, a colonization determinant known to be required for acid adaptation, as critically required for activation of the TLR2/NLRP3/caspase-1 axis. The phenotypes of urease mutants, as well as mouse strains defective for TLR2 or NLRP3, are discussed with respect to their ability to support persistent colonization, immune tolerance and immunity to H. pylori.


Asunto(s)
Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Linfocitos T Reguladores/inmunología , Animales , Antígenos Bacterianos/inmunología , Proteínas Portadoras/metabolismo , Caspasa 1/metabolismo , Infecciones por Helicobacter/metabolismo , Humanos , Tolerancia Inmunológica , Inflamasomas , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR , Transducción de Señal , Receptor Toll-Like 2/metabolismo
19.
Cell Rep ; 13(1): 70-79, 2015 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-26411687

RESUMEN

The human bacterial pathogen Helicobacter pylori exhibits genotoxic properties that promote gastric carcinogenesis. H. pylori introduces DNA double strand breaks (DSBs) in epithelial cells that trigger host cell DNA repair efforts. Here, we show that H. pylori-induced DSBs are repaired via error-prone, potentially mutagenic non-homologous end-joining. A genome-wide screen for factors contributing to DSB induction revealed a critical role for the H. pylori type IV secretion system (T4SS). Inhibition of transcription, as well as NF-κB/RelA-specific RNAi, abrogates DSB formation. DSB induction further requires ß1-integrin signaling. DSBs are introduced by the nucleotide excision repair endonucleases XPF and XPG, which, together with RelA, are recruited to chromatin in a highly coordinated, T4SS-dependent manner. Interestingly, XPF/XPG-mediated DNA DSBs promote NF-κB target gene transactivation and host cell survival. In summary, H. pylori induces XPF/XPG-mediated DNA damage through activation of the T4SS/ß1-integrin signaling axis, which promotes NF-κB target gene expression and host cell survival.


Asunto(s)
Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades , Proteínas de Unión al ADN/genética , Endonucleasas/genética , Células Epiteliales/metabolismo , Helicobacter pylori/genética , Proteínas I-kappa B/genética , Proteínas Nucleares/genética , Factores de Transcripción/genética , Línea Celular Tumoral , Supervivencia Celular , Cromatina/química , Cromatina/metabolismo , Proteínas de Unión al ADN/metabolismo , Endonucleasas/metabolismo , Células Epiteliales/microbiología , Células Epiteliales/patología , Helicobacter pylori/crecimiento & desarrollo , Helicobacter pylori/patogenicidad , Interacciones Huésped-Patógeno , Humanos , Proteínas I-kappa B/metabolismo , Proteínas Inhibidoras de la Apoptosis/genética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Inhibidor NF-kappaB alfa , FN-kappa B/genética , FN-kappa B/metabolismo , Proteínas Nucleares/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transducción de Señal , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/metabolismo , Factores de Transcripción/metabolismo , Activación Transcripcional , Sistemas de Secreción Tipo IV/genética , Sistemas de Secreción Tipo IV/metabolismo
20.
J Clin Invest ; 125(8): 3297-302, 2015 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-26214524

RESUMEN

Inflammasome activation and caspase-1-dependent (CASP1-dependent) processing and secretion of IL-1ß and IL-18 are critical events at the interface of the bacterial pathogen Helicobacter pylori with its host. Whereas IL-1ß promotes Th1 and Th17 responses and gastric immunopathology, IL-18 is required for Treg differentiation, H. pylori persistence, and protection against allergic asthma, which is a hallmark of H. pylori-infected mice and humans. Here, we show that inflammasome activation in DCs requires the cytoplasmic sensor NLRP3 as well as induction of TLR2 signaling by H. pylori. Screening of an H. pylori transposon mutant library revealed that pro-IL-1ß expression is induced by LPS from H. pylori, while the urease B subunit (UreB) is required for NLRP3 inflammasome licensing. UreB activates the TLR2-dependent expression of NLRP3, which represents a rate-limiting step in NLRP3 inflammasome assembly. ureB-deficient H. pylori mutants were defective for CASP1 activation in murine bone marrow-derived DCs, splenic DCs, and human blood-derived DCs. Despite colonizing the murine stomach, ureB mutants failed to induce IL-1ß and IL-18 secretion and to promote Treg responses. Unlike WT H. pylori, ureB mutants were incapable of conferring protection against allergen-induced asthma in murine models. Together, these results indicate that the TLR2/NLRP3/CASP1/IL-18 axis is critical to H. pylori-specific immune regulation.


Asunto(s)
Asma/prevención & control , Proteínas Bacterianas/inmunología , Proteínas Portadoras/inmunología , Helicobacter pylori/inmunología , Péptidos y Proteínas de Señalización Intercelular/inmunología , Receptor Toll-Like 2/inmunología , Ureasa/inmunología , Animales , Asma/genética , Asma/inmunología , Proteínas Bacterianas/genética , Proteínas Portadoras/genética , Células Dendríticas/inmunología , Regulación de la Expresión Génica/efectos de los fármacos , Helicobacter pylori/genética , Humanos , Inflamasomas/genética , Inflamasomas/inmunología , Péptidos y Proteínas de Señalización Intercelular/genética , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Ratones , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR , Receptor Toll-Like 2/genética , Ureasa/genética
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