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BACKGROUND: Although patients with melanoma of unknown primary (MUP) have a better prognosis than similar-staged melanoma patients with known primary, the occurrence of brain metastases (BM) entails a serious complication. This study provides an overview of the incidence, treatment patterns, and overall survival (OS) of adult patients with BM-MUP in the Netherlands. METHODS: BM-MUP cases were retrieved from the Netherlands Cancer Registry. Patient, disease and treatment-related characteristics were summarised using descriptive statistics. Overall survival (OS) was calculated by the Kaplan-Meier method, and the impact of prognostic factors on OS was assessed using Cox proportional hazard regression analyses. RESULTS: Among 1779 MUP patients, 450 were identified as BM-MUP (25.3%). Of these patients, 381 (84.7%) presented with BM along with other metastases, while 69 (15.3%) had BM only. BM-MUP patients were predominantly male (68.2%), and had a median age of 64 years at diagnosis (interquartile range 54-71 years). Over time, the proportion of BM along other metastatic sites increased, and the occurrence of BM decreased (p = 0.01). 1-Year OS improved for the total population, from 30.0% (95% confidence interval (CI): 19.8-40.9%) in 2011-2012 to 43.6% (95%CI: 34.5-52.3%) in 2019-2020, and median OS more than doubled from 4.2 months (95%CI: 3.3-6.2 months) to 9.8 months (95%CI: 7.0-13.2 months). Patient's age, localisation of BM, presence of synchronous liver metastasis and treatment were identified as independent predictors of OS. CONCLUSION: Notwithstanding the progress made in OS for patients with BM-MUP in the past decade, their overall prognosis remains poor, and further efforts are needed to improve outcomes.
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Neoplasias Encefálicas , Melanoma , Neoplasias Primárias Desconhecidas , Humanos , Adulto , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Neoplasias Primárias Desconhecidas/patologia , Países Baixos/epidemiologia , Melanoma/epidemiologia , Melanoma/terapia , Melanoma/patologia , Prognóstico , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Estudos RetrospectivosRESUMO
The Achilles tendon is the strongest tendon in the human body but its mechanical behaviour during failure has been little studied and the basis of its high tensile strength has not been elucidated in detail. In the present study, healthy, human, Achilles tendons were loaded to failure in an anatomically authentic fashion while the local deformation and strains were studied in real time, with very high precision, using digital image correlation (DIC). The values determined for the strength of the Achilles tendon were at the high end of those reported in the literature, consistent with the absence of a pre-existing tendinopathy in the samples, as determined by careful gross inspection and histology. Early in the loading cycle, the proximal region of the tendon accumulated high lateral strains while longitudinal strains remained low. However, immediately before rupture, the mid-substance of the Achilles tendon, its weakest part, started to show high longitudinal strains. These new insights advance the understanding of the mechanical behaviour of tendons as they are stretched to failure.
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Tendão do Calcâneo , Tendinopatia , Fenômenos Biomecânicos , Humanos , Técnicas In Vitro , RupturaRESUMO
PURPOSE: Cancers of an unknown primary site (CUPs) have a dismal prognosis, and the situation is even worse for CUPs patients with brain metastases (BM-CUPs). This study aims to give better insight into the occurrence and survival of BM-CUPs patients. METHODS: Cases were selected from the Netherlands Cancer Registry (1,430 BM-CUPs/17,140 CUPs). Baseline characteristics between CUPs patients with and without BM were tested using chi-square tests and Mann-Whitney U tests. Patients' overall survival (OS) times were estimated by the Kaplan-Meier method and prognostic factors on OS was assessed using Cox proportional hazards regression analyses. RESULTS: The proportion of BM-CUPs patients among CUPs increased from 8% in 2009-2010 to 10% in 2017-2018 (p < 0.001). Most patients presented with multiple brain lesions (53%). Survival of BM-CUPs improved over time: one-year OS increased from 10% for patients diagnosed in 2009-2010 to 17% (2017- 2018) (p < 0.01), and median survival times increased from 1.8 months to 2.2 months. Independent predictors of poor survival were multiple (HR 1.25; p < 0.01) or unknown (HR 1.48; p < 0.01) locations of BM, unknown/poorly/undifferentiated carcinoma histology (HR 1.53; p < 0.01), or clinical symptoms of BM (HR 1.74; p < 0.01), accompanying liver metastasis (HR 1.43; p < 0.01) and more than one metastatic site outside the brain compared to none (HR 1.52; p < 0.01). CONCLUSION: The incidence of patients with BM-CUPs is steadily increasing over time and overall prognosis remains dismal. Our results, however, show distinct patient subgroups that exhibit comparatively better outcomes, and more predictors may likely still be identified.
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Neoplasias Encefálicas , Neoplasias Primárias Desconhecidas , Neoplasias Encefálicas/patologia , Humanos , Neoplasias Primárias Desconhecidas/patologia , Países Baixos/epidemiologia , Prognóstico , Sistema de Registros , Estudos RetrospectivosRESUMO
AIM: To explore the relationship of urinary concentrations of different congeners of benzophenones and parabens with the utilization of cosmetics and personal care products (PCPs) and their impact on the risk of endometriosis, and to evaluate the influence of oxidative stress on associations found. METHODS: This case-control study comprised a subsample of 124 women (35 cases; 89 controls). Endometriosis was confirmed (cases) or ruled out (controls) by laparoscopy, with visual inspection of the pelvis and biopsy of suspected lesions (histological diagnosis). Urinary concentrations of benzophenone-1 (BP-1), benzophenone-3 (BP-3), 4-hydroxibenzophenone (4-OH-BP), methyl- (MeP), ethyl- (EtP), propyl- (PrP), and butyl-paraben (BuP), and biomarkers of oxidative stress [lipid peroxidation (TBARS) and total antioxidant power (TAP)] were quantified. Information was gathered on the frequency of use of cosmetics and PCPs. Associations between the frequency of cosmetics/PCP use, urinary concentrations of benzophenones and parabens, oxidative stress, and endometriosis risk were explored in logistic and linear multivariable regression analyses. RESULTS: The frequency of utilization of certain cosmetics and PCPs was significantly associated with urinary concentrations of benzophenones and parabens. After adjustment for potential confounders, the risk of endometriosis was increased in women in the second versus first terciles of MeP (OR = 5.63; p-value<0.001), BP-1 (OR = 5.12; p-value = 0.011), BP-3 (OR = 4.98; p-value = 0.008), and Æ©BPs (OR = 3.34; p-value = 0.032). A close-to-significant relationship was observed between TBARS concentrations and increased endometriosis risk (OR = 1.60, p-value = 0.070) and an inverse association between TAP concentrations and this risk (OR = 0.15; p-value = 0.048). Oxidative stress results did not modify associations observed between benzophenone/paraben exposure and endometriosis risk. CONCLUSIONS: Our findings indicate that the frequency of cosmetics and PCP utilization is a strong predictor of exposure to certain benzophenone and paraben congeners. These compounds may increase the risk of endometriosis in an oxidative stress-independent manner. Further studies are warranted to corroborate these findings.
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Benzofenonas/toxicidade , Cosméticos , Endometriose , Parabenos/toxicidade , Estudos de Casos e Controles , Endometriose/induzido quimicamente , Endometriose/epidemiologia , Feminino , HumanosRESUMO
There is much interest in understanding the influence of the immune system on bone healing, including a number of reports suggesting a beneficial effect of FK506 (tacrolimus) in this regard. The influence of FK506 in a rat, femoral, critical size defect was examined using locally implanted, recombinant, human (rh) BMP-2 and adenovirally-transduced, autologous, adipose-derived mesenchymal stromal cells (AD-MSCs) expressing BMP-2. FK506 was delivered systemically using an implanted osmotic pump. Empty defects and those implanted with unmodified AD-MSCs did not heal in the presence or absence of FK506. Defects treated with rhBMP-2 healed with a large callus containing thin cortices and wispy trabeculae; this, too, was unaffected by FK506. A third of defects implanted with adenovirally-transduced AD-MSCs healed, but this improved to 100 % in the presence of FK506. New bone formed in response to BMP-2 synthesised endogenously by the genetically modified cells had a slimmer callus than those healed by rhBMP-2, with improved cortication and advanced reconstitution of marrow. These results suggest that FK506 may have had little effect on the intrinsic biology of bone healing, but improved healing in response to adenovirally-transduced cells by inhibiting immune responses to the first-generation adenovirus used here. Because the genetically modified cells produced bone of higher quality at far lower doses of BMP-2, this approach should be explored in subsequent research.
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Diáfises/patologia , Fêmur/patologia , Tacrolimo/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 2/metabolismo , Diáfises/diagnóstico por imagem , Diáfises/efeitos dos fármacos , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fibrina/metabolismo , Masculino , Ratos Endogâmicos F344 , Torção MecânicaRESUMO
Newborn screening (NBS) prevents morbidity and mortality by screening babies for selected disorders in the first days of life so that early diagnosis and treatment can be initiated. Congenital disorders impact an estimated 8 million or 6% of annual births worldwide, and of the top five that contribute 25% to the global burden of these disorders, three can be identified and managed by NBS. There are determined pockets of activity in Latin America, Sub-Saharan Africa, and the Asia Pacific region, where partnerships among government, non-governmental organizations, academia, the private sector and civil society are developing novel NBS programs that are both saving lives and preventing disability in those who survive.
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Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/genética , Triagem Neonatal/história , Triagem Neonatal/métodos , Doenças Genéticas Inatas/epidemiologia , Genética Populacional , Saúde Global , História do Século XX , História do Século XXI , Humanos , Recém-NascidoRESUMO
ã We report on an infant with Opitz trigonocephaly C syndrome (OTCS), who also had manifestations of ciliopathy, including short ribs (non-asphyxiating), trident acetabular roofs, postaxial polydactyly cone-shaped epiphyses, and dysplasia of the renal, hepatic and pancreatic tissues. To investigate the molecular cause, we used an exome sequencing strategy followed by Sanger sequencing. Two rare variants, both predicted to result in loss of functional protein, were identified in the IFT140 gene; a substitution at the splice donor site of exon 24 (c.723 + 1 G > T) and a 17 bp deletion, impacting the first coding exon (c.-11_6del). The variants were confirmed as being biallelic using Sanger sequencing, showing that the splice variant was inherited from the propositus mother and the deletion from the father. To date, Mainzer-Saldino syndrome, Jeune syndrome, and a form of nonsyndromic retinal dystrophy, have been identified as ciliopathies caused by IFT140 mutations. We provide the first description of an OTCS phenotype that appears to result from IFT140 mutations. The presentation of this patient is consistent with previous reports showing that OTCS already exhibited skeleletal and nonskeletal features of a ciliopathy.
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Proteínas de Transporte/genética , Ciliopatias/genética , Craniossinostoses/genética , Predisposição Genética para Doença , Deficiência Intelectual/genética , Ciliopatias/diagnóstico , Ciliopatias/fisiopatologia , Craniossinostoses/diagnóstico , Craniossinostoses/fisiopatologia , Exoma/genética , Feminino , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/fisiopatologia , Masculino , Linhagem , Sítios de Splice de RNA/genética , Deleção de Sequência/genéticaRESUMO
BACKGROUND: As has occurred in many regions worldwide, in 2012 the incidence of pertussis increased in Perú. This epidemiologic situation has been associated with a waning vaccine-induced immunity and the adaptation of Bordetella pertussis to vaccine-induced immunity along with improved diagnostic methods. METHODS: The study comprised a total of 840 pertussis-suspected cases reported in Perú during 2012. We summarize here the distribution of pertussis cases according to age and immunization status along with the immunization-coverage rate. Laboratory diagnosis was performed by culture test and real-time polymerase-chain reaction (PCR). B. pertussis bacteria recovered from infected patients were characterized by pulsed-field gel electrophoresis (PFGE), and the DNA sequencing of the pertussis-toxin (promoter and subunit A), pertactin, and fimbriae (fim2 and fim3) genes. RESULTS: From the total pertussis-suspected cases, 191 (22.7 %) infections were confirmed by real-time PCR and 18 through cultivation of B. pertussis (2.1 %), while one infection of B. parapertussis (0.11 %) was also detected by culture. Pertussis was significantly higher in patients that had had 0-3 vaccine doses (pentavalent vaccine alone) than in those who had had 4-5 vaccine doses (pentavalent plus DwPT boosters) at 94.3 vs. 5.7 %, respectively (p < 0.00001). The relative risk (RR) for patients with 4-5 doses compared to those with fewer than 4 doses or no dose was 0.23 (95 % Confidence Interval: 0.11-0.44), while the vaccine effectiveness was 77 % and coverage 50.5 %. Genetic analysis of B. pertussis isolates from different Peruvian regions detected two clonal groups as identified by PFGE. Those two groups corresponded to the B. pertussis genotypes emerging worldwide ptxP3-ptxA1-prn2 or 9-fim3-1 and ptxP3-ptxA1-prn2 or 9-fim3-2. CONCLUSIONS: Two emerging B. pertussis genotypes similar to isolates involved in worldwide epidemics were detected in Perú. Low vaccine coverage (<50 %) and genetic divergence between the vaccine-producing strain and the local isolates could contribute to this pertussal epidemic.
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Bordetella pertussis/genética , Coqueluche/epidemiologia , Coqueluche/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas da Membrana Bacteriana Externa/genética , Bordetella pertussis/isolamento & purificação , Bordetella pertussis/patogenicidade , Criança , Pré-Escolar , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Humanos , Imunização/estatística & dados numéricos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Toxina Pertussis/genética , Vacina contra Coqueluche/administração & dosagem , Peru/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real , Vacinação/estatística & dados numéricos , Fatores de Virulência de Bordetella/genética , Coqueluche/imunologia , Adulto JovemRESUMO
Multiple genetic and environmental etiologies contribute to the pathogenesis of cleft palate, which is the most common of the inherited disorders of the craniofacial complex. Insights into the molecular mechanisms regulating osteogenic differentiation and patterning in the palate during embryogenesis are limited and needed for the development of innovative diagnostics and cures. This study used the Pax9-/- mouse model with a consistent phenotype of cleft secondary palate to investigate the role of Pax9 in the process of palatal osteogenesis. Although prior research has identified the upregulation of Wnt pathway modulators Dkk1 and Dkk2 in Pax9-/- palate mesenchyme, limitations of spatial resolution and technology restricted a more robust analysis. Here, data from single-nucleus transcriptomics and chromatin accessibility assays validated by in situ highly multiplex targeted single-cell spatial profiling technology suggest a distinct relationship between Pax9+ and osteogenic populations. Loss of Pax9 results in spatially restricted osteogenic domains bounded by Dkk2, which normally interfaces with Pax9 in the mesenchyme. Moreover, the loss of Pax9 leads to a disruption in the normal osteodifferentiaion of palatal osteogenic mesenchymal cells. These results suggest that Pax9-dependent Wnt signaling modulators influence osteogenic programming during palate formation, potentially contributing to the observed cleft palate phenotype.
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BACKGROUND/AIMS: Human papillomavirus (HPV) is an epitheliotropic, double-stranded DNA virus, and its high-risk genotypes are associated with human cancer. HPV genome has been detected in lung carcinomas in certain places around the world, including Mexico; however, the prevalence of this is unclear. In this study, we examine the frequency of high-risk HPV 16/18 in lung cancer tissues from a Mexican population. METHODS: 39 lung cancer specimens were analyzed by polymerase chain reaction (PCR) using HPV GP5+/GP6+ primers and then were genotyped using specific primers to HPV 16/18. Additionally, in situ hybridization (ISH) was performed using BIO-labeled oligonucleotide probes. RESULTS: Our results identified 15 positive cases (38.46%) for HPV 16 and 1 positive case (2.56%) for HPV 18 by PCR. ISH showed the presence of HPV DNA in 13 of 16 (81%) samples, in agreement with the PCR results. CONCLUSIONS: In this study, we detected HPV 16/18 gene sequences in lung cancer samples obtained from Mexican patients by PCR and ISH. We found the highest prevalence of HPV 16 infection in lung adenocarcinomas, suggesting that HPV infection may be associated with lung cancer. However, further studies are needed to elucidate the role of HPV in lung carcinogenesis.
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Adenocarcinoma/virologia , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Neoplasias Pulmonares/virologia , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Adenocarcinoma/complicações , DNA Viral/genética , Feminino , Genótipo , Humanos , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/complicações , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase , PrevalênciaRESUMO
Globally, the increase in medically complex obstetric patients is challenging the educational approach and clinical management of critically ill obstetric patients. This increase in medical complexity calls into question the educational paradigm in which future physicians are trained. Obstetric anesthesiologists, physician experts in the perio-perative planning and management of complex obstetric patients, represent an essential workforce in the strategies to address maternal mortality. Unfortunately, the development of peri-operative medicine and maternal critical care curricula has only received minor attention in most countries. Proposed guidelines and models highlight the existing need for tiered maternity care services in which critical care infrastructure plays a central role in the delivery of high-risk peripartum care. Therefore, the development of maternal critical care models designed to prepare obstetric anesthesiologists for the clinical challenges of a medically complex patient are warranted. Key critical care topics such as advanced ultrasonography, with the inclusion of quantitative echocardiographic assessments into obstetric anesthesiology educational curricula, will serve to better prepare physicians for the realities of an increasingly complex pregnant patient population, and further reinforce the critical care infrastructure detailed in the Levels of Maternal Care consensus. Despite an increasingly complex obstetric patient population, heterogeneity of maternal critical care practices exists across the globe, warranting standardization and further development of proposed curricula.
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Anestesia Obstétrica , Anestesiologistas , Cuidados Críticos , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Anestesiologistas/educação , EcocardiografiaRESUMO
The NADPH oxidase 1 (NOX1) complex formed by proteins NOX1, p22phox, NOXO1, NOXA1, and RAC1 plays an important role in the generation of superoxide and other reactive oxygen species (ROS) which are involved in normal and pathological cell functions due to their effects on diverse cell signaling pathways. Cell migration and invasiveness are at the origin of tumor metastasis during cancer progression which involves a process of cellular de-differentiation known as the epithelial-mesenchymal transition (EMT). During EMT cells lose their polarized epithelial phenotype and express mesenchymal marker proteins that enable cytoskeletal rearrangements promoting cell migration, expression and activation of matrix metalloproteinases (MMPs), tissue remodeling, and cell invasion during metastasis. In this work, we explored the importance of the peroxiredoxin 6 (PRDX6)-NOX1 enzyme interaction leading to NOXA1 protein stabilization and increased levels of superoxide produced by NOX in hepatocarcinoma cells. This increase was accompanied by higher levels of N-cadherin and MMP2, correlating with a greater capacity for cell migration and invasiveness of SNU475 hepatocarcinoma cells. The increase in superoxide and the associated downstream effects on cancer progression were suppressed when phospholipase A2 or peroxidase activities of PRDX6 were abolished by site-directed mutagenesis, reinforcing the importance of these catalytic activities in supporting NOX1-based superoxide generation. Overall, these results demonstrate a clear functional cooperation between NOX1 and PRDX6 catalytic activities which generate higher levels of ROS production, resulting in a more aggressive tumor phenotype.
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Peroxiredoxin 6 (PRDX6), the only mammalian 1-Cys member of the peroxiredoxin family, has peroxidase, phospholipase A2 (PLA2), and lysophosphatidylcholine (LPC) acyltransferase (LPCAT) activities. It has been associated with tumor progression and cancer metastasis, but the mechanisms involved are not clear. We constructed an SNU475 hepatocarcinoma cell line knockout for PRDX6 to study the processes of migration and invasiveness in these mesenchymal cells. They showed lipid peroxidation but inhibition of the NRF2 transcriptional regulator, mitochondrial dysfunction, metabolic reprogramming, an altered cytoskeleton, down-regulation of PCNA, and a diminished growth rate. LPC regulatory action was inhibited, indicating that loss of both the peroxidase and PLA2 activities of PRDX6 are involved. Upstream regulators MYC, ATF4, HNF4A, and HNF4G were activated. Despite AKT activation and GSK3ß inhibition, the prosurvival pathway and the SNAI1-induced EMT program were aborted in the absence of PRDX6, as indicated by diminished migration and invasiveness, down-regulation of bottom-line markers of the EMT program, MMP2, cytoskeletal proteins, and triggering of the "cadherin switch". These changes point to a role for PRDX6 in tumor development and metastasis, so it can be considered a candidate for antitumoral therapies.
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In order to understand T cell function, it is necessary to completely decipher the molecular dynamics underlying T cell activation and effector function. In vitro easy-to-handle cellular models are valuable tools to study intracellular molecular mechanisms in live cells. The CD4 T cell line Jurkat (JK) has been widely employed to investigate intracellular signaling leading to T cell activation in response to T cell receptor (TCR) triggering. Here, we describe diverse, complementary protocols to evaluate the TCR- and costimulation-mediated T cell activation, as well as the immunological synapse assembly and cytokine production occurring as a consequence of successful early activation events. This in vitro model is extremely useful to address molecular mechanisms operating during T cell activation and effector function acting in diverse pathophysiological scenarios.
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Linfócitos T CD4-Positivos , Receptores de Antígenos de Linfócitos T , Humanos , Linfócitos T CD4-Positivos/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Expressão Gênica , Ativação Linfocitária , Células JurkatRESUMO
PURPOSE: This study aims to compare the ability of the PHI versus tPSA test to predict the presence of PCa in our population. METHODS: A prospective observational study was performed. We included patients with tPSA ≥ 2.5 ng/ml, biopsy naïve or previous negative biopsy, undergoing a blood test, which includes tPSA, fPSA, and p2PSA, and a prostate biopsy between March 2019 and March 2022. Patients with PCa found in the biopsy-Group A-were compared with patients with a negative biopsy result-Group B. Diagnostic accuracy of tPSA and PHI was assessed by receiver operating characteristic [ROC] curves and logistic regression. RESULTS: 140 men were included. Fifty-seven (40.7%) had a positive prostate biopsy result (Group A), and 83 (59.3%) had a negative biopsy result (Group B). The mean age was similar in both groups (mean ± standard deviation), 66.86 ± 6.61 years. No difference was found in the tPSA value between the groups (Group A PSA: 6.11 ng/ml (3.56-17.01); Group B: 6.42 ng/ml (2.46-19.45), p = 0.41). The mean value of PHI was statistically different between groups (Group A 65.50 (29-146) vs. Group B 48 (16-233), p = 0.0001). The area under the curve 0.44 for tPSA and 0.77 for PHI. The multivariate logistic regression model applied to PHI showed a significant increase in its predictive accuracy: 72.14% in the model without PHI, 76.09% with PHI. CONCLUSION: The PHI test improves PCa detection compared to tPSA in our population.
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Antígeno Prostático Específico , Neoplasias da Próstata , Masculino , Humanos , Próstata/patologia , Neoplasias da Próstata/patologia , Curva ROC , Estudos Prospectivos , BiópsiaRESUMO
Redoxins are involved in maintenance of thiol redox homeostasis, but their exact sites of action are only partly known. We have applied a combined redox proteomics and transcriptomics experimental strategy to discover specific functions of two interacting redoxins: dually localized glutaredoxin 2 (Grx2p) and mitochondrial peroxiredoxin 1 (Prx1p). We have identified 139 proteins showing differential postranslational thiol redox modifications when the cells do not express Grx2p, Prx1p, or both and have mapped the precise cysteines involved in each case. Some of these modifications constitute functional switches that affect metabolic and signaling pathways as the primary effect, leading to gene transcription remodeling as the secondary adaptive effect as demonstrated by a parallel high throughput gene expression analysis. The results suggest that in the absence of Grx2p, the metabolic flow toward nucleotide and aromatic amino acid biosynthesis is slowed down by redox modification of the key enzymes Rpe1p (D-ribulose-5-phosphate 3-epimerase), Tkl1p (transketolase) and Aro4p (3-deoxy-D-arabino-heptulosonate-7-phosphate synthase). The glycolytic mainstream is then diverted toward carbohydrate storage by induction of trehalose and glycogen biosynthesis genes. Porphyrin biosynthesis may also be compromised by inactivation of the redox-sensitive cytosolic enzymes Hem12p (uroporphyrinogen decarboxylase) and Sam1p (S-adenosyl methionine synthetase) and a battery of respiratory genes sensitive to low heme levels are induced. Genes of the Aft1p-dependent iron regulon were induced specifically in the absence of Prx1p despite optimal mitochondrial Fe-S biogenesis, suggesting dysfunction of the mitochondria to the cytosol signaling pathway. Strikingly, requirement of Grx2p for these events places dithiolic Grx2 in the framework of iron metabolism.
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Glutarredoxinas/metabolismo , Ferro/metabolismo , Peroxirredoxinas/metabolismo , Proteoma/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Compostos de Sulfidrila/metabolismo , Perfilação da Expressão Gênica , Proteínas Mitocondriais , Oxirredução , Processamento de Proteína Pós-TraducionalRESUMO
The antitumor potential of Gymnosperma glutinosum was previously reported using the in vitro and in vivo L5178Y-R lymphoma murine model. The present study was carried out to isolate and identify the cytotoxic compounds present in the Gymnosperma glutinosum leaf hexane extract. Gymnosperma glutinosum was collected in the semi-arid region of Escobedo, State of Nuevo León, México, but it is commonly found in northeastern Mexico; it is traditionally used as a treatment for diarrhea, ulcers and rheumatism. G. glutinosum leaves were extracted with hexane and further fractioned and subfractioned over silica gel by gradient elution with hexane, chloroform, ethyl acetate and methanol. The cytotoxicity of fractions and subfractions was assessed in vitro against L5178Y-R lymphoma cells. Structure elucidation of the active compounds was determined by spectroscopic methods. Fractions and subfractions showed significant (p < 0.05) and concentration-dependent 20% to 56% cytotoxicity against L5178Y-R cells at concentrations ranging from 7.8 µg/mL to 500 µg/mL. The bioassay-guided fractionation of the hexane extract resulted in the isolation and identification of the alkane hentriacontane and the diterpene ent-labd-7-en-13S,14R,15-triol as the metabolites responsible for the activity.
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Alcanos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Asteraceae/química , Diterpenos/farmacologia , Linfoma/patologia , Extratos Vegetais/farmacologia , Alcanos/química , Alcanos/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Diterpenos/química , Diterpenos/isolamento & purificação , México , Camundongos , Extratos Vegetais/química , Folhas de Planta/químicaRESUMO
Microbial entomopathogen-based bioinsecticides are recognized as alternatives to synthetic pesticides. Insects defend themselves against microbial pathogens by innate mechanisms, including increased phenoloxidase (PO) activity, but its relationship with microbial bioinsecticides efficacy is little known. This study evaluated the differences in PO activity at different developmental stages of the tobacco budworm Heliothis virescens Fabricius (Lepidoptera: Noctuidae), Indian meal moth Plodia interpunctella (Hübner) (Pyralidae), beet armyworm Spodoptera exigua (Hübner) (Noctuidae), and cabbage looper Trichoplusia ni (Hübner) (Noctuidae). Additionally, 2(nd)- and 4(th)-instars were exposed to the LC(50) value of the commercial Bacillus thuringiensis (Bt) spray, Biobit(®). The percentage of insecticidal activity (IA%) on 2(nd)-instar Biobit-exposed larvae was approximately the predicted 50 % mortality for all species except S. exigua. With all 4(th) instar Biobit-exposed larvae, mortality was not significantly different from that of unexposed larvae. Unexposed insects had a significantly higher PO activity in pre-pupae and pupae than early-instar larvae and adults, whereas PO activity was higher in adult females than in males. Correlation analysis between IA% and PO activity revealed significant r-values (p < 0.01) in 2(nd) instar H. virescens (r = 0.979) and P. interpunctella (r = 0.930). Second instar Biobit-exposed P. interpunctella had 10 times more PO activity than unexposed larvae. Similarly, the amount of total protein was lower in 4(th) instar Biobit-exposed H. virescens and higher in S. exigua. Therefore, the results indicated a relationship between Biobit susceptibility and PO activity in some cases. This information may be useful if the Biobit application period is timed for a developmental stage with low PO activity. However, more studies are needed to determine the correlation of each insect with a particular bioinsecticide.
Assuntos
Bacillus thuringiensis/fisiologia , Proteínas de Insetos/metabolismo , Inseticidas/farmacologia , Monofenol Mono-Oxigenase/metabolismo , Mariposas/enzimologia , Mariposas/microbiologia , Controle Biológico de Vetores , Animais , Feminino , Imunidade Inata , Larva/enzimologia , Larva/crescimento & desenvolvimento , Larva/imunologia , Larva/microbiologia , Masculino , Mariposas/crescimento & desenvolvimento , Mariposas/imunologia , Pupa/enzimologia , Pupa/crescimento & desenvolvimento , Pupa/imunologia , Pupa/microbiologia , Especificidade da Espécie , Spodoptera/enzimologia , Spodoptera/crescimento & desenvolvimento , Spodoptera/imunologia , Spodoptera/microbiologia , Fatores de TempoRESUMO
Amongst many high-income countries, indirect medical conditions (e.g. cardiovascular disease, sepsis) now account for the majority of maternal deaths. In response to this concerning rise in indirect causes of maternal deaths, professional societies have developed guidelines that regionalize high-risk obstetric care and prioritize critical care expertise as a requirement for designated 'top' maternity hospitals. Critical care proficiency is mandated by the Accreditation Council for Graduate Medical Education for graduating obstetric anesthesiology fellows. Despite these requirements, no formal obstetric critical care educational curricula or fellowship pathways, combining critical care medicine and obstetric anesthesiology, currently exist. Dual subspecialty training in both obstetric anesthesiology and critical care medicine represents one strategy to improve the care of critically-ill obstetric patients and reduce maternal mortality and morbidity, which is one of the pressing healthcare issues of our time.