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Here, the dynamics of inverse tapered granular chains, which are alignments of beads with progressively increasing radii, are investigated. These chains are subjected to harmonic excitation by a moving wall and probed at the tapered end. Intermediate taperings using Ni-Ti (metal) and Teflon (plastic) granules are considered. The proposed chain is based on the frequency responses. The incident signal is set between 1 Hz and 3 kHz. The system transmits or filters incident signals at low or high driving frequencies, respectively. For intermediate frequencies, similar to the human voice and most musical instruments, the driving frequency is amplified, presenting a median gain of 24 dB (an increase in energy by a factor of 250) over long durations. A transition map, showing regions of transmission, amplification, and filtration as a function of driving amplitude and frequency, is provided. This system could serve as a starting point for studies on natural voice amplifiers, which are important for addressing hearing loss and vocal disorders, as well as other applications requiring mechanical signal amplification. The findings suggest that a proper granular arrangement could enable the amplification of low or extremely low driving frequencies.

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Globally, colorectal cancer (CRC) is one of the most frequently diagnosed human gastrointestinal neoplasia and the second leading cause of cancer-related death in both men and women. Despite considerable efforts currently devoted to the study of the biology and treatment of CRC, patient prognosis and survival are still poor. Sporadic CRC is a complex multistep disease and usually emerges in the setting of lifestyle and dietary changes mainly observed in industrialized countries with high human development index (HDI) (westernized style). The molecular pathogenesis of sporadic CRC presents genetic heterogeneity with APC, RAS, PIK3CA, TGFBR, SMAD4, and TP53 mutations usually detected during the progression of this malignancy. The establishment of sporadic CRC models has become essential for both basic and translational research to improve our understanding of the pathophysiology, unravel new molecular drivers, and preventive/therapeutic improvement of this malignancy. Chemically induced rodent models of sporadic CRC recapitulate most key morphological and genetic/epigenetic events observed during the promotion and progression of this malignancy, establishing effective diagnostic and prevention strategies to be translated into clinical practice. The present review gathers the main features of the state-of-the-art evidence on chemically induced rodent models, widely applied for translational modelling of sporadic CRC with a specific focus on histopathology and prevention perspectives. Our narrative review reinforces the persistent value of these bioassays and encourages the use of multimodel strategies for further investigations.

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Capsaicin (CAP) is the compound responsible for pungency in chili peppers, presenting several biological properties. But its general safety and effectiveness in the context of carcinogenesis has not been fully clarified. Thus, the present study evaluated whether dietary CAP modifies the development of urothelial lesions induced by the carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in male Sprague-Dawley rats. Animals were randomly allocated into 6 groups: G1 - treated with 0.05% BBN in drinking water (weeks 1-12) and received a balanced diet (weeks 1-20); G2 and G3-treated with BBN (weeks 1-12) and received a balanced diet with 0.01 or 0.02% CAP (weeks 1-20), respectively; G4 and G5- only received a balanced diet with 0.01 or 0.02% CAP (weeks 1-20), respectively; G6 - only received a balanced diet (weeks 1-20). At the end of week 20, the incidence and types of urothelial lesions, proliferating cell nuclear antigen (PCNA) labeling index, and matrix metalloproteinases (MMP) 2 and 9 activities were analyzed. A significant reduction was observed in the incidence and multiplicity of simple (p = 0.020 and p = 0.011) and nodular/papillary (p = 0.030 and p = 0.003) hyperplasias and papillomas/carcinomas (p = 0.023 and p = 0.020), epithelial proliferation (p = 0.007) and in the activity of the intermediate form of MMP-2 (p < 0.001) and pro-MMP-9 activities (p < 0.002), in BBN + 0.02% CAP (G3) group in comparison to BBN (G1) group. Capsaicin intake per se did not alter body weight, liver and kidney weights, urothelial histology or serum biochemical parameters. Thus, dietary CAP was safe and showed a protective effect against rat BBN-induced urothelial carcinogenesis.

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Colorectal cancer is the third most diagnosed cancer worldwide and linked to dietary/lifestyle factors. Arthrospira (Spirulina) platensis (AP) contains bioactive compounds with beneficial effects in vivo/in vitro. We evaluated the effects of AP feeding against 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis. Male Sprague Dawley rats were given subcutaneous injections of DMH (4 × 40 mg/kg body weight) (G1-G3) or vehicle (G4-G5) twice a week (weeks 3-4). During weeks 1-4, animals were fed a diet containing 1 % (G2) or 2 % (G3-G4) AP powder (w/w). After this period, all groups received a balanced diet until week 12. Some animals were euthanised after the last DMH injection (week 4) for histological, immunohistochemical (Ki-67, γ-H2AX and caspase-3) and molecular analyses (real time-PCR for 91 genes), while other animals were euthanised at week 12 for preneoplastic aberrant crypt foci (ACF) analysis. Both AP treatments (G2-G3) significantly decreased the DMH-induced increase in γ-H2AX (DNA damage) and caspase 3 (DNA damage-induced cell death) in colonic crypts at week 4. In addition, Cyp2e1 (Drug metabolism), Notch1, Notch2 and Jag1 genes (Notch pathway) and Atm, Wee1, Chek2, Mgmt, Ogg1 and Xrcc6 genes (DNA repair) were also down-regulated by 2 % AP feeding (G3) at week 4. A significant reduction in ACF development was observed in both AP-treated groups (G2-G3) at week 12. In conclusion, findings indicate that AP feeding reduced acute colonic damage after DMH, resulting in fewer preneoplastic lesions. Our study provided mechanistic insights on dietary AP-preventive effects against early colon carcinogenesis.

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This research evaluated the biomass productivity and nutritional value of the haylage and hay from intercropping between Tamani grass and different legume species. For the productive characteristics of the different intercrops, we adopted a randomized block design, for evaluation of the combination of intercropping and conservation technic we used 5 x 2 factorial scheme (five intercrops and two types of conservation techniques). The treatments were Tamani grass as monoculture, and the intercrops of Tamani grass with crotalaria, soybean, cowpea, or pigeon pea. The conservation techniques were haylage (520 g/kg of DM) and hay (870 g/kg of DM). Plants were sown in alternate rows, with 45 cm of spacing between the rows. The parameters evaluated were grass and legume biomass production, canopy height, and haylage and hay chemical composition, and in vitro dry matter digestibility (ivDMD). There were no differences in the total biomass production between the intercrops and TA grass monoculture. The treatments intercropped with cowpea and soybean had the highest legume participation in the mixture, promoting an increase in crude protein and ivDMD content of haylage and hay. Haylage and hay had the same chemical composition, although haylage had higher ivDMD than hay. We concluded that intercropping Tamani grass with soybeans or cowpea maintained total biomass productivity and improved the nutritional value of haylage and hay.

Esta pesquisa foi realizada com o objetivo de se avaliar a produtividade da biomassa e valor nutricional da silagem e do feno provenientes do consórcio entre o capim-Tamani e diferentes espécies de leguminosas. Para as características produtivas das diferentes culturas consorciadas, adotamos o delineamento de blocos ao acaso, para avaliação da interação dos consórcios com técnicas de conservação usamos esquema fatorial 5 x 2 (cinco consórcios e duas técnicas de conservação). Os tratamentos foram o capim-Tamani em monocultura, e o consórcio de capim-Tamni associado a crotalária, soja, feijão-caupi ou feijão-guandu. As plantas foram semeadas em fileiras alternadas, com espaçamento de 45 cm. As técnicas de conservação foram silagem pré-secada (520 g / kg de MS) e feno (870 g / kg de MS). Avaliamos a produção de biomassa de gramínea e leguminosa, a altura do dossel, a composição química e a digestibilidade in vitro da matéria seca (ivDMD). Não houve diferenças na produção total de biomassa entre os consórcios e o monocultivo de capim-Tamani. Os tratamentos consorciados com feijão-caupi e soja tiveram maior participação de leguminosas na mistura, promovendo aumento no teor de proteína bruta e ivDMD da silagem pré-secada e feno. A silagem pré-secada e o feno tinham a mesma composição química, embora a silagem pré-secada apresentou maior ivDMD do que o feno. Concluímos que o consórcio de capim-Tamani com soja ou feijão-caupi manteve a produtividade da biomassa total e melhorou o valor nutricional da silagem pré-secada e do feno.

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Pyoderma gangrenosum manifests as an ulceration of the skin often associated with several systemic diseases. The diagnosis is usually made by exclusion criteria with suggestions made by clinical findings and histological features. It can occur any site but more common in the legs. Advances in translational medicine led to the development of new forms of therapy in chronic inflammatory diseases by the oral administration of Janus kinase inhibitors. We report two cases of chronic ulceration of the skin consistent with the diagnosis of Pyoderma Gangrenosum that went into complete remission after the use of baricitinib.

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We propose a granular architecture as a potential impact protector and signal filter. The system consists of monodispersed granular chains decorated with side beads fixed (welded) on sidewalls. Numerical results from usual monodispersed chains and simple tapered chains are employed as reference. An appropriate material combination and an optimal radii ratio between the side and axial granules show that more than 90% of the momentum amplitude of solitary pulses can be attenuated using a small and scalable system composed of five axial granules. Considering sinusoidal signals, the findings suggest that regular chains (monodispersed and tapered) are low-pass filters with cutoff frequencies as functions of the driven amplitude, restitutional losses, and tapering. The granular chain with fixed decoration filters all the input signals.

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Capsaicin (CPS), an ingredient of Capsicum plants, has anti-inflammatory, antioxidant and antitumoral properties. The mechanisms of CPS on hepatocarcinogenesis preclinical bioassays are not described. Thus, the protective effects CPS were evaluated in the early stages of chemically-induced hepatocarcinogenesis. Male Wistar rats received diet containing 0.01% or 0.02% CPS for 3 weeks. Afterwards, animals received a dose of hepatocarcinogen diethylnitrosamine (DEN, 100 mg/kg body weight). From weeks 4-12, groups had their diet replaced by a 0.05% phenobarbital supplemented one to promote DEN-induced preneoplastic lesions. Animals were euthanized 24 h after DEN administration (n = 5/group) or at week 12 (n = 9/group). The estimated CPS intake in rats resembled human consumption. At the end of week 3, dietary 0.02% CPS attenuated DEN-induced oxidative damage and, consequently, hepatocyte necrosis by reducing serum alanine aminotransferase levels, liver CD68-positive macrophages, lipid peroxidation, while increasing antioxidant glutathione system. Additionally, 0.02% CPS upregulated vanilloid Trpv1 receptor and anti-inflammatory epoxygenase Cyp2j4 genes in the liver. Ultimately, previous 0.02% CPS intake decreased the number of GST-P-positive preneoplastic lesions at week 12. Thus, CPS attenuated preneoplastic lesion development, primarily by diminishing DEN-induced oxidative liver injury. Findings indicate that CPS is a promising chemopreventive agent when administered after and during the early stages of hepatocarcinogenesis.

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Background: The metacarpal/metatarsophalangeal joints, as well as the suspensory apparatus, are usually affected by injuries, due to the intense physical demand during sports and great range of motion, predisposing to degenerative processes,trauma and rupture of the suspensory apparatus. In this case, arthrodesis is the main technique indicated. Such surgicaltechniques have a poor prognosis due to post-surgical complications, such as implant infection. Therefore, the study ofprocedures that promote better joint stabilization is important, with reduced surgical time and tissue exposure, decreasingsignificantly the chance of infection and other possible complications.Case: A 5-year-old male horse was referred to the hospital with a history of trauma and a lacerating wound in the metatarsalplantar region of the left hindlimb. The animal presented grade IV (I-V) claudication of the left hindlimb with hyperextension of the metatarsophalangeal joint and significant pain on palpation, evidencing the rupture of the superficial, deep digitalflexor tendons and suspensory ligament of the fetlock. The initial surgical treatment was performed using the arthrodesistechnique described by [16]. The intramedullary nail was used with fixation of the plate on the plantar face of the first phalanx together with a single plate fused to the pin, adjusted according to size of the first phalanx, 13 mm thick x 15 cm long,forming an angle between 120º and 140º. Twenty-four h after surgery, there was a simple spiral diaphyseal fracture (typeA), in the middle third of the third metatarsal bone in the region of the proximal end, due to the lever held by the short nailagainst the diaphysis cortex. To treat the complication, an intramedullary 316 L surgical steel rod 13 mm thick x 21 cm longwas used, filling the entire spinal canal. The nail had three holes at the proximal end and two holes at the distal end...(AU)

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Background: The metacarpal/metatarsophalangeal joints, as well as the suspensory apparatus, are usually affected by injuries, due to the intense physical demand during sports and great range of motion, predisposing to degenerative processes,trauma and rupture of the suspensory apparatus. In this case, arthrodesis is the main technique indicated. Such surgicaltechniques have a poor prognosis due to post-surgical complications, such as implant infection. Therefore, the study ofprocedures that promote better joint stabilization is important, with reduced surgical time and tissue exposure, decreasingsignificantly the chance of infection and other possible complications.Case: A 5-year-old male horse was referred to the hospital with a history of trauma and a lacerating wound in the metatarsalplantar region of the left hindlimb. The animal presented grade IV (I-V) claudication of the left hindlimb with hyperextension of the metatarsophalangeal joint and significant pain on palpation, evidencing the rupture of the superficial, deep digitalflexor tendons and suspensory ligament of the fetlock. The initial surgical treatment was performed using the arthrodesistechnique described by [16]. The intramedullary nail was used with fixation of the plate on the plantar face of the first phalanx together with a single plate fused to the pin, adjusted according to size of the first phalanx, 13 mm thick x 15 cm long,forming an angle between 120º and 140º. Twenty-four h after surgery, there was a simple spiral diaphyseal fracture (typeA), in the middle third of the third metatarsal bone in the region of the proximal end, due to the lever held by the short nailagainst the diaphysis cortex. To treat the complication, an intramedullary 316 L surgical steel rod 13 mm thick x 21 cm longwas used, filling the entire spinal canal. The nail had three holes at the proximal end and two holes at the distal end...

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Background and Purpose- Sleep apnea has been associated with a poor outcome in acute stroke patients. Polysomnography is the gold standard diagnostic method for sleep apnea, but it is not feasible as a routine in the acute stroke setting. The current generation of positive airway pressure (PAP) devices can detect the different types of respiratory events. This study aimed to compare the algorithms used in PAP device to manually scored events on polysomnography in patients with acute stroke. Methods- A sleep study was performed with standard polysomnography and PAP device, simultaneously, within the first 48 hours after acute stroke onset. Results- We prospectively evaluated 29 patients with acute stroke (59.5±12.1 years). The area under the receiver operating characteristic curve for each apnea-hypopnea index value was above 0.90 by PAP device. There was a good correlation of apnea-hypopnea index (rs=0.92; P<0.001), hypopnea index (rs=0.89; P<0.001), and apnea index (rs=0.70; P<0.001) between device-detected events and manually scored polysomnography. Conclusions- Given the high frequency of sleep apnea during the acute phase of stroke and the complexity of a full polysomnography study in this setting, PAP device on diagnostic mode can be used as an alternative tool for sleep apnea detection in acute stroke patients.

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Background: The metacarpophalangeal and metatarsophalangeal joints are very demanded during high intensity exercises,and may be affected by osteoarthritis, fractures, luxations and rupture of the suspensory apparatus. Thus, arthrodesis maybe indicated to restore joint stability and accelerate the ankylosis process. The most commonly used surgical techniqueshave been associated with postoperative complications, including infection and failure of the implants, so it is importantto develop procedures that are less invasive procedures and promoting stable fixation. Therefore, the aim of this work isto report the use of the modified steel basket technique for metatarsophalangeal arthrodesis in a foal with hyperextensionof the joint due to rupture of the digital flexor muscles.Case: A 2-day-old male foal was admitted to clinical care, presenting multiple cutaneous wounds caused by dogs bites,located in the tarsus and thigh of the hindlimb. The animal presented in standing position and had no difficulty of movement,being initially treated through daily cleaning of the cutaneous wounds and systemic antibiotic therapy. Hyperextension ofthe metatarsophalangeal joint was evidenced after 20 days, being approached through tenotomy and tendon shortening,followed by tenorrhaphy and immobilization for 30 days. Due to the failure of the treatment, it was opted for metatarsophalangeal arthrodesis by modified steel basket technique. The procedure involved the implantation of a steel basket of25.0 mm in diameter x 25.0 mm long in a 24.0 mm hole created on the dorsal surface between the third metacarpal andthe proximal phalanx. The basket was filled with bone extracted from drilling and fixed with two cortical screws at anangle of 25° toward proximoplantar and distoplantar direction. Immobilization of the limb was performed postoperativelywith synthetic plaster cast for 45 days and, due to the persistence of lameness...(AU)

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Background: The metacarpophalangeal and metatarsophalangeal joints are very demanded during high intensity exercises,and may be affected by osteoarthritis, fractures, luxations and rupture of the suspensory apparatus. Thus, arthrodesis maybe indicated to restore joint stability and accelerate the ankylosis process. The most commonly used surgical techniqueshave been associated with postoperative complications, including infection and failure of the implants, so it is importantto develop procedures that are less invasive procedures and promoting stable fixation. Therefore, the aim of this work isto report the use of the modified steel basket technique for metatarsophalangeal arthrodesis in a foal with hyperextensionof the joint due to rupture of the digital flexor muscles.Case: A 2-day-old male foal was admitted to clinical care, presenting multiple cutaneous wounds caused by dogs bites,located in the tarsus and thigh of the hindlimb. The animal presented in standing position and had no difficulty of movement,being initially treated through daily cleaning of the cutaneous wounds and systemic antibiotic therapy. Hyperextension ofthe metatarsophalangeal joint was evidenced after 20 days, being approached through tenotomy and tendon shortening,followed by tenorrhaphy and immobilization for 30 days. Due to the failure of the treatment, it was opted for metatarsophalangeal arthrodesis by modified steel basket technique. The procedure involved the implantation of a steel basket of25.0 mm in diameter x 25.0 mm long in a 24.0 mm hole created on the dorsal surface between the third metacarpal andthe proximal phalanx. The basket was filled with bone extracted from drilling and fixed with two cortical screws at anangle of 25° toward proximoplantar and distoplantar direction. Immobilization of the limb was performed postoperativelywith synthetic plaster cast for 45 days and, due to the persistence of lameness...

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ABSTRACT Objective: Magnetic resonance imaging (MRI) is paramount in the assessment of knee pathology, particularly when planning for a surgical procedure. This study compared the diagnostic accuracy in MRI reading of pathological knees by radiologists and orthopaedic surgeons. Materials and methods: Cross-sectional study comprising 80 randomly selected patients previously submitted to arthroscopic surgery after clinical examination and MRI. A diagnosis by MRI interpretation was requested from the two teams, one of radiologists and another of orthopaedic surgeons. The conclusions of each team were later compared. Statistical significance was considered for p < 0.05. Results: The radiologists' findings achieved statistical significance regarding osteochondral injuries, ACL, and medial meniscus (p < 0.05), and orthopaedic surgeons regarding ACL injuries and menisci (p < 0.05). ACL injuries demonstrated a statistically significant association between teams (p < 0.001). Conclusions: MRI appears to offer reliable readings of ACL injuries, regardless the specialty of the observer. The lateral compartment is scarcely well read.

RESUMO Objetivo: A ressonância magnética (RM) é primordial na avaliação de patologias do joelho, particularmente no planejamento de um procedimento cirúrgico. Este estudo comparou a precisão diagnóstica na leitura dos resultados da RM de joelhos patológicos por radiologistas e cirurgiões ortopédicos. Materiais e métodos: Estudo transversal com 80 pacientes, selecionados aleatoriamente, previamente submetidos à cirurgia artroscópica após exame clínico e RM. Foi solicitado um diagnóstico por RM a duas equipes, uma de radiologistas e outra de cirurgiões ortopédicos. As conclusões de cada equipe foram comparadas. A significância estatística considerada foi de p < 0,05. Resultados: Os achados dos radiologistas obtiveram significância estatística para lesões osteocondrais, do LCA e do menisco medial (p < 0,05); os achados dos cirurgiões ortopédicos, para lesões no LCA e meniscos (p < 0,05). Uma associação estatisticamente significativa entre equipes foi demonstrada para lesões do LCA (p < 0,001). Conclusões: A RM parece oferecer leituras confiáveis para lesões do LCA, independentemente da especialidade do observador. O compartimento lateral é de difícil leitura.

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PI3K/Akt/mTOR pathway activation is a hallmark of high-grade gliomas, which prompted clinical trials for the use of PI3K and mTOR inhibitors. However, the poor results in the original trials suggested that better patient profiling was needed for such drugs. Thus, accurate and reproducible monitoring of mTOR complexes can lead to improved therapeutic strategies. In this work, we evaluated the expression and phosphorylation of mTOR, RAPTOR, and rpS6 in 195 human astrocytomas and 30 normal brain tissue samples. The expression of mTOR increased in glioblastomas, whereas mTOR phosphorylation, expression of RAPTOR, and expression and phosphorylation of rpS6 were similar between grades. Interestingly, the overexpression of total and phosphorylated mTOR as well as phosphorylated rpS6 (residues 240-244) were associated with wild-type IDH1 only glioblastomas. The expression and phosphorylation of mTOR and phosphorylation of rpS6 at residues 240-244 were associated with a worse prognosis in glioblastomas. Our results suggest that mTOR and rpS6 could be used as markers of overactivation of the PI3K-mTOR pathway and are predictive factors for overall survival in glioblastomas. Our study thus suggests that patients who harbor IDH1 wild-type glioblastomas might have increased benefit from targeted therapy against mTOR.

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OBJECTIVE: Magnetic resonance imaging (MRI) is paramount in the assessment of knee pathology, particularly when planning for a surgical procedure. This study compared the diagnostic accuracy in MRI reading of pathological knees by radiologists and orthopaedic surgeons. MATERIALS AND METHODS: Cross-sectional study comprising 80 randomly selected patients previously submitted to arthroscopic surgery after clinical examination and MRI. A diagnosis by MRI interpretation was requested from the two teams, one of radiologists and another of orthopaedic surgeons. The conclusions of each team were later compared. Statistical significance was considered for p < 0.05. RESULTS: The radiologists' findings achieved statistical significance regarding osteochondral injuries, ACL, and medial meniscus (p < 0.05), and orthopaedic surgeons regarding ACL injuries and menisci (p < 0.05). ACL injuries demonstrated a statistically significant association between teams (p < 0.001). CONCLUSIONS: MRI appears to offer reliable readings of ACL injuries, regardless the specialty of the observer. The lateral compartment is scarcely well read.

OBJETIVO: A ressonância magnética (RM) é primordial na avaliação de patologias do joelho, particularmente no planejamento de um procedimento cirúrgico. Este estudo comparou a precisão diagnóstica na leitura dos resultados da RM de joelhos patológicos por radiologistas e cirurgiões ortopédicos. MATERIAIS E MÉTODOS: Este foi um estudo transversal com 80 pacientes, selecionados aleatoriamente, previamente submetidos à cirurgia artroscópica após exame clínico e RM. Foi solicitado um diagnóstico por RM a duas equipes, uma de radiologistas e outra de cirurgiões ortopédicos. As conclusões de cada equipe foram comparadas posteriormente. A significância estatística considerada foi de p < 0,05. RESULTADOS: Os achados dos radiologistas obtiveram significância estatística para lesões osteocondrais, do LCA e do menisco medial (p < 0,05); os achados dos cirurgiões ortopédicos, para lesões no LCA e meniscos (p < 0,05). Uma associação estatisticamente significativa entre equipes foi demonstrada para lesões do LCA (p < 0,001). CONCLUSÕES: A RM parece oferecer leituras confiáveis para lesões do LCA, independentemente da especialidade do observador. O compartimento lateral é de difícil leitura.