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Herbivorous insects alter biogeochemical cycling within forests, but the magnitude of these impacts, their global variation, and drivers of this variation remain poorly understood. To address this knowledge gap and help improve biogeochemical models, we established a global network of 74 plots within 40 mature, undisturbed broadleaved forests. We analyzed freshly senesced and green leaves for carbon, nitrogen, phosphorus and silica concentrations, foliar production and herbivory, and stand-level nutrient fluxes. We show more nutrient release by insect herbivores at non-outbreak levels in tropical forests than temperate and boreal forests, that these fluxes increase strongly with mean annual temperature, and that they exceed atmospheric deposition inputs in some localities. Thus, background levels of insect herbivory are sufficiently large to both alter ecosystem element cycling and influence terrestrial carbon cycling. Further, climate can affect interactions between natural populations of plants and herbivores with important consequences for global biogeochemical cycles across broadleaved forests.
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Bosques , Herbivoria , Insectos , Nitrógeno , Hojas de la Planta , Temperatura , Herbivoria/fisiología , Animales , Insectos/fisiología , Hojas de la Planta/metabolismo , Nitrógeno/metabolismo , Carbono/metabolismo , Ciclo del Carbono , Fósforo/metabolismo , Ecosistema , Árboles/metabolismoRESUMEN
OBJECTIVE: The precise indications for employing the anterior component separation technique (ACST) and the Transversus Abdominis Release (TAR) in abdominal wall reconstruction (AWR) remain uncertain, despite the undeniable value of both techniques. The aim of this study was to analyze the anterior fascial closure rate, postoperative wound morbidity, and hernia recurrence rate for both procedures according to the algorithm used for complex AWR. METHODS: A retrospective analysis of prospectively collected data was carried out. Patients undergoing AWR for midline incisional hernias using either open or endoscopic ACST (E-ACST) or TAR between March 2013 and August 2022 were included. Patients with lateral hernia components were excluded. The surgical technique was depending on the pre- and intraoperative findings regarding hernia width and on the estimated traction to achieve anterior fascial closure (see algorithm). Initially, intermediate hernia defects ranging from approximately 10-14 cm in width were repaired using E-ACST. However, as the study advanced, TAR became the preferred method for addressing these types of defects. Open ACST was consistently employed for defects wider than 14-15 cm throughout the entire study duration. Outcomes of interest were anterior fascial closure, surgical site occurrences, and hernia recurrence rate. Follow-up was performed at 1 month, 1 year, and 2 years. RESULTS: A total of 119 patients underwent AWR with CST: 63 patients (52.9%) were included in the ACST group and 56 patients (47.1%) in the TAR group. No significant differences were observed in patient and hernia characteristics. The use of botulinum toxin A (BTA) injection and preoperative progressive pneumoperitoneum (PPP) was more frequently used in the ACST group (BTA 19.0%, PPP 15.9% versus BTA 5.4%, PPP 1.8% for TAR patients). Anterior fascial closure was achieved in 95.2% of the ACST group and 98.2% of the TAR group (p = 0.369). The TAR group demonstrated a significantly lower SSO rate at one month (44.3% versus 14.3%, p < 0.001) and required fewer procedural interventions (SSO-PI) (31.1% versus 8.9%, p = 0.003). The recurrence rate at one year was low and there was no statistically significant difference between the two groups (ACST 1.8% vs TAR 4.5%, p = 0.422). CONCLUSION: Following a proposed algorithm, the anterior fascial closure rate was high and similar for both techniques. As postoperative wound morbidity is significantly increased after ACST, our findings support recommending TAR for defects up to 14 cm in width, while favoring open ACST for larger defects.
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Pared Abdominal , Algoritmos , Hernia Incisional , Recurrencia , Humanos , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Pared Abdominal/cirugía , Anciano , Hernia Incisional/cirugía , Herniorrafia/métodos , Herniorrafia/efectos adversos , Hernia Ventral/cirugía , Adulto , Músculos Abdominales , Técnicas de Cierre de Herida Abdominal , Complicaciones PosoperatoriasRESUMEN
PURPOSE: Abdominal compartment syndrome (ACS) is a well-known concept after trauma surgery or after major abdominal surgery in critically ill patients. However, ACS as a complication after complex hernia repair is considered rare and supporting literature is scarce. As complexity in abdominal wall repair increases, with the introduction of new tools and advanced techniques, ACS incidence might rise and should be carefully considered when dealing with complex abdominal wall hernias. In this narrative review, a summary of the current literature will highlight several key features in the diagnosis and management of ACS in complex abdominal wall repair and discuss several treatment options during the different steps of complex AWR. METHODS: We performed a literature search across PubMed using the search terms: "Abdominal Compartment syndrome," "Intra-abdominal pressure," "Complex abdominal hernia," and "Ventral hernia." Articles corresponding to these search terms were individually reviewed by primary author and selected on relevance. CONCLUSION: Intra-abdominal hypertension (IAH) and ACS require imperative attention and should be carefully considered when dealing with complex abdominal wall hernias, even without significant loss of domain. Development of a true abdominal compartment syndrome is relatively rare, but is a devastating complication and should be prevented at all cost. Current evidence on surgical treatment of ACS after hernia repair is scarce, but conservative management might be an option in the early phase and low grades of IAH. However, life-saving treatment by relaparotomy and open abdomen management should be initiated when ACS starts setting in.
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Herniorrafia , Hipertensión Intraabdominal , Complicaciones Posoperatorias , Humanos , Hipertensión Intraabdominal/etiología , Herniorrafia/efectos adversos , Complicaciones Posoperatorias/etiología , Hernia Ventral/cirugía , Hernia Ventral/complicacionesRESUMEN
PURPOSE: Using small instead of large bites for laparotomy closure results in lower incidence of incisional hernia, but no consensus exists on which suture material to use. This study aimed to compare five different closure strategies in a standardized experimental setting. METHODS: Fifty porcine abdominal walls were arranged into 5 groups: (A) running 2/0 polydioxanone; (B) interlocking 2/0 polydioxanone; (C) running size 0 barbed polydioxanone; (D) running size 0 barbed glycolic acid and trimethylene carbonate; (E) running size 0 suturable polypropylene mesh. The small-bites technique was used for linea alba closure in all. The abdominal walls were divided into a supra- and infra-umbilical half, resulting in 20 specimens per group that were pulled apart in a tensile testing machine. Maximum tensile force and types of suture failure were registered. RESULTS: The highest tensile force was measured when using barbed polydioxanone (334.8 N ± 157.0), but differences did not reach statistical significance. Infra-umbilical abdominal walls endured a significantly higher maximum tensile force compared to supra-umbilical (397 N vs 271 N, p < 0.001). Barbed glycolic acid and trimethylene carbonate failed significantly more often (25% vs 0%, p = 0.008). CONCLUSION: Based on tensile force, both interlocking and running suture techniques using polydioxanone, and running sutures using barbed polydioxanone or suturable mesh, seem to be suitable for abdominal wall closure. Tensile strength was significantly higher in infra-umbilical abdominal walls compared to supra-umbilical. Barbed glycolic acid and trimethylene carbonate should probably be discouraged for fascial closure, because of increased risk of suture failure.
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Pared Abdominal , Técnicas de Cierre de Herida Abdominal , Glicolatos , Porcinos , Animales , Pared Abdominal/cirugía , Polidioxanona , Herniorrafia , Técnicas de Sutura/efectos adversos , Modelos Animales , Resistencia a la Tracción , Laparotomía , Suturas , Técnicas de Cierre de Herida Abdominal/efectos adversosRESUMEN
Many mesocarnivores are fossorial and use burrow systems to avoid predators. But fossorial animals cannot stay safely underground forever; they must also risk emerging overground to forage and find mates. To make this trade-off effectively and maximise their own fitness, it is imperative they assess how risk varies in space and time and adapt their denning behaviour accordingly. We used the badger in Bialowieza Forest, Poland, as a model for investigating how the denning behaviour of a fossorial mesocarnivore varies in response to short-term large carnivore risk. To this end, we experimentally simulated perceived wolf presence outside 10 badger setts using audio playbacks of wolves (their howls). We assayed two behavioural measures of fear: badger emergence time from setts on the day playbacks were broadcast and their presence in setts on the day after. We found that neither badger emergence time nor next-day sett use varied in response to wolf playbacks. The results of the present study contrast with a previous study of ours that found badgers used setts in areas with high landscape level perceived wolf risk less often than those in lower-risk areas. Together, these papers' findings suggest that different spatiotemporal scales of perceived risk can have differential effects on badger behaviour. We conclude that rather than take risk avoidance measures at all risky times and places, badgers likely display a diversity of reactions to large carnivore presence that depend on the context and spatiotemporal scale of the risk being perceived.
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Large carnivores not only supress mesocarnivores via killing and instilling fear, but also facilitate them through carrion provisioning. Hence, mesocarnivores frequently face a trade-off between risk avoidance and food acquisition. Here we used the raccoon dog and red fox in Bialowieza Forest, Poland as models for investigating how large carnivores shape mesocarnivore foraging behaviour in an area with widespread large carnivore carrion provisioning. Using a giving up density experiment we quantified mesocarnivore foraging responses to wolf body odour across a landscape-scale gradient in wolf encounter rates. At locations with higher wolf encounter rates, raccoon dogs depleted feeding trays more than at plots with lower wolf encounter rates. Simulating wolf presence by adding wolf body odour caused raccoon dogs to deplete feeding trays more at locations with low wolf encounter rates, but less at locations with high wolf encounter rates. Fox foraging costs did not vary with the application of wolf body odour or wolf encounter rates. The frequency that the mesocarnivores visited experimental foraging patches was unaffected by wolf body odour or landscape level encounter rates. These results provide further evidence that large carnivore suppression can play a subordinate role to facilitation in determining mesocarnivore behaviour. The varying raccoon dog response to wolf odour across the landscape-scale gradient in wolf encounter rates shows how mesocarnivore-large carnivore interactions can be context-dependent. We suggest that rather than testing the effects of single risk cues on prey behaviour, future studies should focus on understanding how context modifies the ecological impacts of large carnivores.
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Carnívoros , Lobos , Animales , Ecosistema , Miedo , Conducta Predatoria , Perros MapacheRESUMEN
This study examined the effect of perceived predation risk imposed by lynx (Lynx lynx) and wolf (Canis lupus) on red deer (Cervus elaphus) foraging behavior under experimental conditions. We hypothesized that in response to large carnivore scent red deer would increase their vigilance, although reducing the frequency and duration of visits to foraging sites. Consequently, browsing intensity on tree saplings was expected to decrease, whereas a higher proportion of more preferred species was expected to be browsed to compensate for higher foraging costs. We expected stronger responses towards the ambush predator lynx, compared with the cursorial predator wolf. These hypotheses were tested in a cafeteria experiment conducted within three red deer enclosures, each containing four experimental plots with olfactory cues of wolf, lynx, cow, and water as control. On each plot, a camera trap was placed and browsing intensity was measured for one consecutive week, repeated three times. Red deer reduced their visitation duration and browsing intensity on plots with large carnivore scent. Despite red deer showing a clear preference for certain tree species, the presence of large carnivore scent did not change selectivity towards different tree species. Contrary to our hypothesis, we found more pronounced effects of wolf (cursorial) compared with lynx (ambush). This study is the first to experimentally assess the perceived risk effects on the red deer foraging behavior of large carnivores differing in hunting modes. Our findings provide insights into the role of olfactory cues in predator-prey interactions and how they can modify fine-scale herbivore-plant interactions.
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African swine fever (ASF) has been spreading in the Eurasian continent for more than 10 years now. Although the course of ASF in domestic pigs and its negative economic impact on the pork industry are well-known, we still lack a quantitative assessment of the impact of ASF on wild boar (Sus scrofa) populations under natural conditions. Wild boar is not only a reservoir for ASF; it is also one of the key wildlife species affecting structure and functioning of ecosystems. Therefore, knowledge on how ASF affects wild boar populations is crucial to better predict ecosystem response and for the design of scientific-based wild boar management to control ASF. We used a long-term camera trap survey (2012-2017) from the Bialowieza Primeval Forest (BPF, Poland), where an ASF outbreak occurred in 2015, to investigate the impact of the disease on wild boar population dynamics under two contrasting management regimes (hunted vs. non-hunted). In the hunted part of BPF ("managed area"), hunting was drastically increased prior and after the first ASF case occurred (March 2015), whereas inside the National Park, hunting was not permitted ("unmanaged area," first detected case in June 2015). Using a random encounter model (REM), we showed that the density and abundance of wild boar dropped by 84 and 95% within 1 year following ASF outbreak in the unmanaged and managed area, respectively. In the managed area, we showed that 11-22% additional mortality could be attributed to hunting. Our study suggests that ASF-induced mortality, by far, outweighs hunting-induced mortality in causing wild boar population decline and shows that intensified hunting in newly ASF-infected areas does not achieve much greater reduction of population size than what is already caused by the ASF virus.
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Spatial variation in habitat riskiness has a major influence on the predator-prey space race. However, the outcome of this race can be modulated if prey shares enemies with fellow prey (i.e., another prey species). Sharing of natural enemies may result in apparent competition, and its implications for prey space use remain poorly studied. Our objective was to test how prey species spend time among habitats that differ in riskiness, and how shared predation modulates the space use by prey species. We studied a one-predator, two-prey system in a coastal dune landscape in the Netherlands with the European hare (Lepus europaeus) and European rabbit (Oryctolagus cuniculus) as sympatric prey species and red fox (Vulpes vulpes) as their main predator. The fine-scale space use by each species was quantified using camera traps. We quantified residence time as an index of space use. Hares and rabbits spent time differently among habitats that differ in riskiness. Space use by predators and habitat riskiness affected space use by hares more strongly than space use by rabbits. Residence time of hare was shorter in habitats in which the predator was efficient in searching or capturing prey species. However, hares spent more time in edge habitat when foxes were present, even though foxes are considered ambush predators. Shared predation affected the predator-prey space race for hares positively, and more strongly than the predator-prey space race for rabbits, which were not affected. Shared predation reversed the predator-prey space race between foxes and hares, whereas shared predation possibly also released a negative association and promoted a positive association between our two sympatric prey species. Habitat riskiness, species presence, and prey species' escape mode and foraging mode (i.e., central-place vs. noncentral-place forager) affected the prey space race under shared predation.
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Olfactory signals constitute an important mechanism in interspecific interactions, but little is known regarding their role in communication between predator species. We analyzed the behavioral responses of a mesopredator, the red fox (Vulpes vulpes), to an olfactory cue (scat) of an apex predator, the lynx (Lynx lynx) in Bialowieza Primeval Forest, Poland, using video camera traps. Red fox visited sites with scats more often than expected and the duration of their visits was longer at scat sites than at control sites (no scat added). Vigilant behavior, sniffing and scent marking (including over-marking) occurred more often at scat sites compared to control sites, where foxes mainly passed by. Vigilance was most pronounced during the first days of the recordings. Red fox behavior was also influenced by foxes previously visiting scat sites. They sniffed and scent marked (multiple over-marking) more frequently when the lynx scat had been over-marked previously by red fox. Fox visits to lynx scats may be seen as a trade-off between obtaining information on a potential food source (prey killed by lynx) and the potential risk of predation by an apex predator.
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Plant biomass consumers (mammalian herbivory and fire) are increasingly seen as major drivers of ecosystem structure and function but the prevailing paradigm in temperate forest ecology is still that their dynamics are mainly bottom-up resource-controlled. Using conceptual advances from savanna ecology, particularly the demographic bottleneck model, we present a novel view on temperate forest dynamics that integrates consumer and resource control. We used a fully factorial experiment, with varying levels of ungulate herbivory and resource (light) availability, to investigate how these factors shape recruitment of five temperate tree species. We ran simulations to project how inter- and intraspecific differences in height increment under the different experimental scenarios influence long-term recruitment of tree species. Strong herbivore-driven demographic bottlenecks occurred in our temperate forest system, and bottlenecks were as strong under resource-rich as under resource-poor conditions. Increased browsing by herbivores in resource-rich patches strongly counteracted the increased escape strength of saplings in these patches. This finding is a crucial extension of the demographic bottleneck model which assumes that increased resource availability allows plants to more easily escape consumer-driven bottlenecks. Our study demonstrates that a more dynamic understanding of consumer-resource interactions is necessary, where consumers and plants both respond to resource availability.
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Bosques , Herbivoria/fisiología , Mamíferos/fisiología , Árboles/fisiología , Animales , Simulación por Computador , Geografía , Modelos Teóricos , Polonia , Especificidad de la EspecieRESUMEN
Pasturing of livestock in forests has had profound consequences for Europe's landscapes. In Bialowieza Primeval Forest (BPF), cattle pasturing was a part of traditional forest use that ceased only in the second half of the twentieth century. We collected information on the institutional changes governing forest cattle pasturing and the changes in spatial extent of cattle presence in BPF in last two centuries and information on cattle numbers and their impact on forest regeneration. The spatial extent of cattle pasturing was highly variable, with the distribution of grazing areas frequently changing. Forest near villages (constituting less than 10 % of the area) was most often used for cattle grazing during continued longer time periods. Historical data showed that cattle have had a clear impact on forest regeneration. However, the frequent changes that occurred in the extent of cattle grazing indicate that their impact occurred locally, was smaller in other less intensively used areas, and in the forest as a whole.
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Crianza de Animales Domésticos , Conservación de los Recursos Naturales/métodos , Agricultura Forestal , Bosques , Crianza de Animales Domésticos/historia , Crianza de Animales Domésticos/organización & administración , Crianza de Animales Domésticos/tendencias , Animales , Biodiversidad , Bovinos , Conservación de los Recursos Naturales/historia , Conservación de los Recursos Naturales/tendencias , Domesticación , Agricultura Forestal/historia , Agricultura Forestal/organización & administración , Agricultura Forestal/tendencias , Herbivoria , Historia del Siglo XIX , Historia del Siglo XX , Polonia , República de Belarús , Árboles/clasificación , Árboles/crecimiento & desarrolloRESUMEN
Body size of vertebrate herbivores is strongly linked to other life history traits, most notably (1) tolerance of low quality forage and (2) vulnerability to predation, which both impact the composition and dynamics of natural communities. However, no study has thus far explored how the combination of these two body-size related traits affects the long-term composition and dynamics of the herbivore and plant communities. We made a simple model of ordinary differential equations and simulated a grassland system with three herbivore species (small, medium, large) and two predator species (small, large) to investigate how the combination of low-quality tolerance and predation-vulnerability structure the herbivore and plant community. We found that facilitation and competition between different-sized herbivores and predation by especially small predators stimulate coexistence among herbivore species. Furthermore, the interaction between different-sized herbivores and predators generated cyclical succession in the plant community, i.e. alternating periods of short vegetation dominated by high-quality plants, with periods of tall vegetation dominated by low-quality plants. Our results suggest that cyclical succession in plant communities is more likely to occur when a predator predominantly preys on small herbivore species. Large predators also play an important role, as their addition relaxed the set of conditions under which cyclical succession occurred. Consequently, our model predictions suggest that a diverse predator community plays an important role in the long-term dynamics and maintenance of diversity in both the herbivore and plant community.
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Ecosistema , Herbivoria , Modelos Biológicos , Plantas , Conducta Predatoria , Animales , Bison , Tamaño Corporal , Ciervos , Europa (Continente) , Cadena Alimentaria , Zorros , Dinámica Poblacional , LobosRESUMEN
Anti-predator responses by ungulates can be based on habitat features or on the near-imminent threat of predators. In dense forest, cues that ungulates use to assess predation risk likely differ from half-open landscapes, as scent relative to sight is predicted to be more important. We studied, in the Bialowieza Primeval Forest (Poland), whether perceived predation risk in red deer (Cervus elaphus) and wild boar (Sus scrofa) is related to habitat visibility or olfactory cues of a predator. We used camera traps in two different set-ups to record undisturbed ungulate behavior and fresh wolf (Canis lupus) scats as olfactory cue. Habitat visibility at fixed locations in deciduous old growth forest affected neither vigilance levels nor visitation rate and cumulative visitation time of both ungulate species. However, red deer showed a more than two-fold increase of vigilance level from 22% of the time present on control plots to 46% on experimental plots containing one wolf scat. Higher vigilance came at the expense of time spent foraging, which decreased from 32% to 12% while exposed to the wolf scat. These behavioral changes were most pronounced during the first week of the experiment but continuous monitoring of the plots suggested that they might last for several weeks. Wild boar did not show behavioral responses indicating higher perceived predation risk. Visitation rate and cumulative visitation time were not affected by the presence of a wolf scat in both ungulate species. The current study showed that perceived predation risk in red deer and wild boar is not related to habitat visibility in a dense forest ecosystem. However, olfactory cues of wolves affected foraging behavior of their preferred prey species red deer. We showed that odor of wolves in an ecologically equivalent dose is sufficient to create fine-scale risk factors for red deer.
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Señales (Psicología) , Conducta Predatoria , Árboles , Lobos , Animales , Ciervos , Ecosistema , Femenino , Masculino , Odorantes , Polonia , Densidad de PoblaciónRESUMEN
BACKGROUND: Routine outcome monitoring (ROM) means the assessment of the patient's condition on a routine basis using instruments. So far there is no consensus about which instruments should be used for ROM with severely mentally ill patients (ROM-SMI). AIM: To reach a consensus about instruments for ROM-SMI in the Netherlands and Belgium and to create possibilities for comparison of ROM data. METHOD: This article discusses the consensus document of the National Remission Working Group for ROM in patients with smi and covers the following topics: reasons for ROM-SMI, domains for ROM-SMI and appropriate instruments, logistics and analyses of the data. RESULTS: Patients with SMI have problems in several domains. These can be assessed by collecting information about psychiatric symptoms, addiction, somatic problems, general functioning, needs, quality of life and care satisfaction. Potential instruments for ROM-SMI are short, valid, reliable and assess several domains, taking the patient's perspective into account, and have been used in national and international research. The working group advises institutions to choose from a limited set of instruments. After the scores have been aggregated and standardised, comparisons can be drawn. ROM-SMI data can be interpreted more meaningfully, if outcome data are supplemented with data regarding patient characteristics and the treatment interventions already applied. CONCLUSION: It should be possible to reach a consensus about instruments for ROM-SMI and the way in which they should be used. The use of identical instruments will lead to improvements in mental health care and create possibilities for comparison (benchmarking) and research.
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Benchmarking , Trastornos Mentales/terapia , Servicios de Salud Mental/normas , Evaluación de Resultado en la Atención de Salud , Bélgica , Humanos , Trastornos Mentales/patología , Trastornos Mentales/psicología , Países Bajos , Escalas de Valoración Psiquiátrica , Índice de Severidad de la EnfermedadRESUMEN
Clinical features of liver involvement due to Listeria monocytogenes infection in adults are rarely reported in literature. This is surprising, regarding the current opinion that the portal system is extensively involved in the first stages of pathogenesis in invasive L. monocytogenes disease. A literature search in the PubMed and Embase database revealed 34 cases with clinical features of hepatic involvement due to listeriosis. We systematically analyzed all case reports with respect to clinical manifestations, treatment and outcome. In addition, we added clinical information on a patient diagnosed with a solitary liver abscess due to L. monocytogenes, who was seen at our institution. This review describes the different presentations of liver-involvement reported in listeriosis; solitary liver abscess, multiple liver abscesses and diffuse or granulomatous hepatitis. Distinction between these different forms of liver involvement is clinically relevant as they have a different outcome. We delve into the different pathogenic events leading to different forms of liver involvement. In addition, diagnostic modalities and possible treatments are reviewed.
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Hepatitis/microbiología , Listeriosis/complicaciones , Absceso Piógeno Hepático/microbiología , Adulto , Femenino , Hepatitis/diagnóstico por imagen , Hepatitis/terapia , Humanos , Listeria monocytogenes/patogenicidad , Listeriosis/fisiopatología , Listeriosis/terapia , Absceso Piógeno Hepático/diagnóstico por imagen , Absceso Piógeno Hepático/terapia , Masculino , UltrasonografíaRESUMEN
Acutely psychotic patients presenting as psychiatric emergencies with aggression or agitation are often administered conventional antipsychotics intramuscularly. However, patients view intramuscular administration as coercive, and conventional antipsychotics are often associated with adverse events. In this open study, consecutive adult patients presenting with an acute exacerbation of schizophrenia or other psychotic disorder were assigned to oral risperidone 2-6 mg/day (n = 48) or oral zuclopenthixol 20-50 mg/day (n = 27) for 7-14 days. Lorazepam (either oral or intramuscular) was administered to both groups as needed. Patients were assessed regularly until day 14 or discharge. Mean Positive And Negative Syndrome Scale (PANSS) aggression scores (sum of item scores on excitement, poor impulse control, hostility and uncooperativeness) decreased steadily and similarly in both groups; the mean changes from baseline were statistically significant at days 10 and 14 and at study end-point. The mean decrease at study end-point in the PANSS component score for hostility was statistically significant in the risperidone group, but not in the zuclopenthixol group. Social Dysfunction and Aggression Scale aggression scores and Clinical Global Impression scores decreased significantly and similarly in both groups. Overall, 18.7% of patients showed minor extrapyramidal symptoms during the study, but only 16.7% of risperidone-treated patients, compared to 59.3% of zuclopenthixol-treated patients, received anti-parkinsonian medication (p < 0.001). Lorazepam was administered to all of the patients assigned to risperidone and to 89% of those assigned to zuclopenthixol. Oral risperidone plus lorazepam is a convenient, effective and well-tolerated alternative to conventional antipsychotics for the treatment of acute psychosis in emergency psychiatry.