7,288 research outputs found
Splenosis. A diagnosis to be considered
The term splenosis applies to the autotransplanted splenic tissue resulting from seeding in the context of past splenic trauma or surgery. We report a 42-year-old man with a history of splenectomy observed for an incidentally found retrovesical mass thought to be an ectopic testicle. The abdominal laparotomy revealed multiple focuses of pelvic splenosis. As splenosis can be diagnosed through specific imaging studies one should always consider it in differential diagnosis of a mass discovered years after splenic surgery or trauma
Is it worth screening quarry workers for TB infection in high-incidence areas? A cost-benefit analysis
Background: Tuberculosis (TB) infection screening of high-risk groups is an important strategy for achieving End TB targets. A TB infection screening program was implemented for quarry workers from a Portuguese high-incidence area in 2018–2022. We aimed to calculate the cost-benefit of the screening program from the societal perspective. Methods: We calculated medical and non-medical direct and indirect screening costs and compared them with the cost savings from averted cases of TB disease. We estimated the number of potentially averted TB disease cases based on the risk of progression of TB infection to TB disease found in the literature. Results: During the screening program, 997 workers were screened. TB infection was diagnosed in 215 workers, 150 of those initiated preventive treatment. Screening program total costs were €136,295. Twenty-nine TB cases were potentially prevented, what would have costed €152,386. Savings of €16,091 were obtained (€4516, €40898, and -€29322 from the workers, employers, and NHS, respectively). Conclusions: The monetary benefit of a TB infection screening program directed to quarry workers in a high-incidence area was greater than its cost. Companies and workers saved substantially more money. TB infection tests that are better predictors of progression to TB disease could reduce NHS costs. © 2024 The AuthorsNo funding was received for conducting this study. The study was conceived by Sofia Sousa, Álvaro Almeida and Raquel Duarte. Sofia Sousa, Carlos Carvalho, Sofia Santos and Catarina Magalhães Alves collected the data. Sofia Sousa wrote the first draft of the manuscript. All authors reviewed and edited the manuscript. The final manuscript was approved by all authors before submission.The authors have no conflicts of interest to declare
Histological changes and impairment of liver mitochondrial bioenergetics after long-term treatment with alpha-naphthyl-isothiocyanate (ANIT)
This study was designed to evaluate the effects of long-term treatment with alpha-naphthyl-isothiocyanate (ANIT) on liver histology and at the mitochondrial bioenergetic level. Since, ANIT has been used as a cholestatic agent and it has been pointed out that an impairment of mitochondrial function is a cause of hepatocyte dysfunction leading to cholestatic liver injury, serum markers of liver injury were measured and liver sections were analyzed in ANIT-treated rats (i.p. 80 mg/kg/week x 16 weeks). Mitochondrial parameters such as transmembrane potential, respiration, calcium capacity, alterations in permeability transition susceptibility and ATPase activity were monitored. Histologically, the most important features were the marked ductular proliferation, proliferation of mast cells and the presence of iron deposits in ANIT-treated liver. Mitochondria isolated from ANIT-treated rats showed no alterations in state 4 respiration, respiratory control ratio and ADP/O ratio, while state 3 respiration was significantly decreased. No changes were observed on transmembrane potential, but the repolarization rate was decreased in treated rats. Consistently with these data, there was a significant decrease in the ATPase activity of treated mitochondria. Associated with these parameters, mitochondria from treated animals exhibited increased susceptibility to mitochondrial permeability transition pore opening (lower calcium capacity). Since, human cholestatic liver disease progress slowly overtime, these data provide further insight into the role of mitochondrial dysfunction in the process
The application of Bonelike® Poro as a synthetic bone substitute for the management of critical-sized bone defects - A comparative approach to the autograft technique - A preliminary study
The effective treatment of non-unions and critical-sized defects remains a challenge in the orthopedic field. From a tissue engineering perspective, this issue can be addressed through the application bioactive matrixes to support bone regeneration, such as Bonelike®, as opposed to the widespread autologous grafting technique. An improved formulation of Bonelike® Poro, was assessed as a synthetic bone substitute in an ovine model for critical-sized bone defects. Bone regeneration was assessed after 5 months of recovery through macro and microscopic analysis of the healing features of the defect sites. Both the application of natural bone graft or Bonelike® Poro resulted in bridging of the defects margins. Untreated defect remained as fibrous non-unions at the end of the study period. The characteristics of the newly formed bone and its integration with the host tissue were assessed through histomorphometric and histological analysis, which demonstrated Bonelike® Poro to result in improved healing of the defects. The group treated with synthetic biomaterial presented bone bridges of increased thickness and bone features that more closely resembled the native spongeous and cortical bone. The application of Bonelike® Poro enabled the regeneration of critical-sized lesions and performed comparably to the autograph technique, validating its octeoconductive and osteointegrative potential for clinical application as a therapeutic strategy in human and veterinary orthopedics.This research was supported by Projects PEst-OE/AGR/UI0211/2011 from FCT , and COMPETE 2020 , from ANI – Projetos ID&T Empresas em Copromoção , by the project “insitu.Biomas – Reinvent biomanufacturing systems by using an usability approach for in situ clinic temporary implants fabrication” with the reference POCI-01-0247-FEDER-017771 , by the project “Print-on-Organs – Engineering bioinks and processes for direct printing on organs” with the reference POCI-01-0247-FEDER-033877 , and by the project “Bone2Move - Development of ‘in vivo’ experimental techniques and modelling methodologies for the evaluation of 4D scaffolds for bone defect in sheep model: an integrative research approach” with the reference POCI-01-0145-FEDER-031146 . Mariana Vieira Branquinho ( SFRH/BD/146172/2019 ), Ana Catarina Sousa ( SFRH/BD/146689/2019 ), and Rui Damásio Alvites ( SFRH/BD/116118/2016 ), acknowledge FCT , for financial support.
This research was supported by Projects PEst-OE/AGR/UI0211/2011 from FCT, and COMPETE 2020, from ANI ? Projetos ID&T Empresas em Copromo??o, by the project ?insitu.Biomas ? Reinvent biomanufacturing systems by using an usability approach for in situ clinic temporary implants fabrication? with the reference POCI-01-0247-FEDER-017771, by the project ?Print-on-Organs ? Engineering bioinks and processes for direct printing on organs? with the reference POCI-01-0247-FEDER-033877, and by the project ?Bone2Move - Development of ?in vivo? experimental techniques and modelling methodologies for the evaluation of 4D scaffolds for bone defect in sheep model: an integrative research approach? with the reference POCI-01-0145-FEDER-031146. Mariana Vieira Branquinho (SFRH/BD/146172/2019), Ana Catarina Sousa (SFRH/BD/146689/2019), and Rui Dam?sio Alvites (SFRH/BD/116118/2016), acknowledge FCT, for financial support
Transcription factor NRF2 protects mice against dietary iron-induced liver injury by preventing hepatocytic cell death
BACKGROUND & AIMS: The liver, being the major site of iron storage, is particularly exposed to the toxic effects of iron. Transcription factor NRF2 is critical for protecting the liver against disease by activating the transcription of genes encoding detoxification/antioxidant enzymes. We aimed to determine if the NRF2 pathway plays a significant role in the protection against hepatic iron overload.METHODS: Wild-type and Nrf2(-/-) mouse primary hepatocytes were incubated with ferric ammonium citrate. Wild-type and Nrf2(-/-) mice were fed standard rodent chow or iron-rich diet for 2weeks, with or without daily injection of the antioxidant mito-TEMPOL.RESULTS: In mouse hepatocytes, iron induced the nuclear translocation of NRF2 and the expression of cytoprotective genes in an NRF2-dependent manner. Moreover, Nrf2(-/-) hepatocytes were highly susceptible to iron-induced cell death. Wild-type and Nrf2(-/-) mice fed iron-rich diet accumulated similar amounts of iron in the liver and were equally able to increase the expression of hepatic hepcidin and ferritin. Nevertheless, in Nrf2-null mice the iron loading resulted in progressive liver injury, ranging from mild confluent necrosis to severe necroinflammatory lesions. Hepatocytic cell death was associated with gross ultrastructural damage to the mitochondria. Notably, liver injury was prevented in iron-fed animals that received mito-TEMPOL.CONCLUSIONS: NRF2 protects the mouse liver against the toxicity of dietary iron overload by preventing hepatocytic cell death. We identify NRF2 as a potential modifier of liver disease in iron overload pathology and show the beneficial effect of the antioxidant mito-TEMPOL in a mouse model of dietary iron-induced liver injury.This work is funded by FEDER Funds through the Operational Competitiveness Programme - COMPETE and by National Funds through FCT - Fundacao para a Ciencia e a Tecnologia under the project FCOMP-01-0124-FEDER-011062 (PTDC/SAU-FCF/101177/2008). TLD is supported by "Programa Ciencia - financiado pelo POPH - QREN - Tipologia 4.2 - Promocao do Emprego Cientifico, comparticipado pelo Fundo Social Europeu e por fundos nacionais do MCTES''
Physiological and enzymatic changes in rice seeds stored at low temperatures
This study aimed to evaluate the effect of low temperatures on the physiological and enzymatic changes of rice seeds. The seeds were packed in airtight chambers and maintained at temperatures of 8 and -50°C for periods of 15, 30 , 45, 60, 75 and 90 days. The same procedure was adopted for the control treatment with the seeds kept at a temperature of 25°C. The seeds were evaluated regarding germination test; seedling emergency; emergency speed index; length and dry weight of radicle; and seedling of shoot. The activity of amylase and total protein content were also evaluated. The temperatures of 8 and -50°C significantly influenced the physiological quality and the enzyme amylase activity of rice seeds, resulting in higher germination, seedling emergence and enzyme activity. The temperature is a promising alternative for the maintenance of physiological quality and enzymatic activity of rice seeds during storage. Key words: Oryza sativa L., enzymatic activity, physiological quality, storage.Abbreviation: ESI, Emergence speed index; PVP, polyvinylpyrrolidone
Osmotic tolerance and freezability of isolated caprine early-staged follicles
Isolated caprine early-staged follicles were submitted to osmotic tolerance tests in the presence of sucrose, ethylene glycol (EG), or NaCl solutions and were exposed to and cryopreserved (by slow or rapid cooling) in MEM alone or MEM supplemented with sucrose, EG (1.0 or 4.0 M), or both. When follicles were exposed to 1.5 M NaCl, only 2% of the follicles were viable, whereas 87% of the follicles were viable after exposure to 4.0 M EG. Regarding exposure time, the highest percentage of viable follicles was obtained when follicles were exposed for 10 min to 1.0 M EG + 0.5 M sucrose; exposure for 60 s to 4.0 M EG + 0.5 M sucrose also maintained high percentage viability in follicles. Slow cooling in the presence of 1.0 M EG + 0.5 M sucrose (75%) or rapid cooling in the presence of 4.0 M EG + 0.5 M sucrose (71%) resulted in a significantly higher proportion of viable follicles than all other treatments (P < 0.05). A 24-h culture of frozen-thawed follicles was used to assess survival; only slow-frozen follicles showed viability rates similar to control follicles (64% vs. 69% respectively; P > 0.05). Interestingly, the percentage of viable rapid-cooled follicles (59%) was similar to that obtained after in vitro culture of conventional slow-cooled follicles but was significantly lower than that in controls. Thus, in addition to determining improved procedures for the exposure of follicles to EG and sucrose before and after freezing of caprine early-staged follicles, we report the development of rapid- and slow-cooling protocols
The Interstellar Medium In Galaxies Seen A Billion Years After The Big Bang
Evolution in the measured rest frame ultraviolet spectral slope and
ultraviolet to optical flux ratios indicate a rapid evolution in the dust
obscuration of galaxies during the first 3 billion years of cosmic time (z>4).
This evolution implies a change in the average interstellar medium properties,
but the measurements are systematically uncertain due to untested assumptions,
and the inability to measure heavily obscured regions of the galaxies. Previous
attempts to directly measure the interstellar medium in normal galaxies at
these redshifts have failed for a number of reasons with one notable exception.
Here we report measurements of the [CII] gas and dust emission in 9 typical
(~1-4L*) star-forming galaxies ~1 billon years after the big bang (z~5-6). We
find these galaxies have >12x less thermal emission compared with similar
systems ~2 billion years later, and enhanced [CII] emission relative to the
far-infrared continuum, confirming a strong evolution in the interstellar
medium properties in the early universe. The gas is distributed over scales of
1-8 kpc, and shows diverse dynamics within the sample. These results are
consistent with early galaxies having significantly less dust than typical
galaxies seen at z<3 and being comparable to local low-metallicity systems.Comment: Submitted to Nature, under review after referee report. 22 pages, 4
figures, 4 Extended Data Figures, 5 Extended Data table
Optimal interdependence between networks for the evolution of cooperation
Recent research has identified interactions between networks as crucial for the outcome of evolutionary
games taking place on them. While the consensus is that interdependence does promote cooperation by
means of organizational complexity and enhanced reciprocity that is out of reach on isolated networks, we
here address the question just how much interdependence there should be. Intuitively, one might assume
the more the better. However, we show that in fact only an intermediate density of sufficiently strong
interactions between networks warrants an optimal resolution of social dilemmas. This is due to an intricate
interplay between the heterogeneity that causes an asymmetric strategy flow because of the additional links
between the networks, and the independent formation of cooperative patterns on each individual network.
Presented results are robust to variations of the strategy updating rule, the topology of interdependent
networks, and the governing social dilemma, thus suggesting a high degree of universality
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