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1.
J Osteopath Med ; 124(3): 97-106, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37877246

RESUMO

CONTEXT: Cardiovascular disease (CVD) is the leading cause of death in the United States. As such, an unmet need exists in the primary and secondary prevention of adverse cardiovascular events (CVEs). Specifically, identifying drugs that can reduce the progression of CVD and serious adverse events is much needed. Drugs that work by reducing platelet aggregation, blocking cholesterol formation (3-hydroxy-3-methyl-glutaryl-coenzyme A [HMG-CoA] reductase inhibitors), and/or blocking inflammation pathways (mainly interleukin-1b [IL-1b]) have been linked to preventing adverse CVEs, including acetylsalicylic acid (ASA, aspirin), statins, colchicine, and IL-1 inhibitors (interleukin-1 receptor antagonists). This systematic review aims to provide insight into utilizing these four agents for the primary and/or secondary prevention of CVD. OBJECTIVES: In this systematic review, we opted to review the efficacy of aspirin, statins, colchicine, and IL-1 inhibitors in the primary and secondary prevention of CVE to provide clinical practitioners with evidence-based practice approaches and determine any unmet needs in their utilization. METHODS: Between October 1 and 12, 2021, a search was conducted and completed on five databases: PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, and Biomedical Reference Collection: Comprehensive. A total of 13 researchers (V.A., A.H., S.B., V.G., D.C., C.C., C.B., C.A., S.K., J.H., A.K., S.F., and S.E.) were involved in the search and screening of the articles. Search terms included "aspirin, statins, colchicine, IL-1 inhibitors, and primary, secondary, myocardial infarction (MI)." Inclusion criteria included clinical study design, English language articles, all genders older than 50 years old, and established patient history of CVD, including MI. In addition, articles were excluded if they were animal models, in vitro studies, pharmacokinetic studies, systematic reviews, literature reviews, and studies exploring therapies other than those listed in the inclusion criteria. First, five individuals independently sorted through abstracts or articles based on the inclusion and exclusion criteria. Then, a team of 13 individuals sorted through full-text articles of selected abstracts based on the same criteria. A separate researcher resolved conflicts between the team. RESULTS: A total of 725 articles were identified from all databases, from which 256 duplicated articles were removed. Thus, a total of 469 articles abstracts were screened, of which 425 articles either did not meet the inclusion criteria or met the exclusion criteria. A total of 42 articles were retrieved and assessed for full-text review, from which 15 articles were retrieved for analysis. CONCLUSIONS: Statins may prevent primary CVEs based on their role in preventing cholesterol formation. Aspirin, canakinumab, and colchicine may be helpful in the secondary prevention of CVEs due to their blocking of various steps in the inflammation pathway leading to CVD. Future research should primarily focus on the use of canakinumab and colchicine in preventing CVD due to the limited number of studies on these drugs.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Infarto do Miocárdio , Feminino , Humanos , Masculino , Estados Unidos , Pessoa de Meia-Idade , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Aspirina/uso terapêutico , Colchicina/uso terapêutico , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/prevenção & controle , Colesterol , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interleucina-1
2.
Cureus ; 15(10): e47372, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38022038

RESUMO

Tobacco use, hypertension, diabetes, and hypercholesterolemia are known risk factors for peripheral artery disease (PAD). However, additional causes of PAD, such as radiation therapy, should be considered for the prevention and diagnosis of this disease. The patient described in this report had 36 radiation therapies directly to the pelvis and bladder area due to bladder cancer. The presence of severe PAD on this patient's right external iliac artery, the same area where he received radiation therapy, raises the question of whether radiation therapy contributed to the development of PAD. In addition, his history of anal intraepithelial neoplasia, obstructive uropathy, and chronic kidney disease further demonstrated that he possibly suffered extensive tissue damage due to radiation to the pelvis. This case report explores the current diagnosis guidelines and treatment options for patients with radiation-induced PAD. Through this case study, we aim to bring awareness to this lesser-known cause of PAD among medical providers and promote research for the prevention and treatment of this disease.

3.
Cureus ; 15(9): e45261, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37720126

RESUMO

Acute kidney injury (AKI) involves a rapid decline in kidney function, classified into prerenal, intrarenal, and postrenal causes. Drug-induced AKI's complex pathophysiology includes altered hemodynamics, inflammation, crystal deposition, hemolysis, and rhabdomyolysis. This report details a 42-year-old female with hypertension and diabetes who, following a dog bite, exhibited reduced kidney function (GFR: 16 ​​mL/min/1.73m2; BUN/Cr: 23/3.23 mg/dL). A renal ultrasound revealed no stones or masses, and the recent use of tirzepatide was identified. Discontinuation of the drug, IV fluid maintenance, and close monitoring led to swift kidney function improvement. This case underscores the importance of recognizing drug-induced AKI, even in unrelated complaints, and highlights the need for vigilance and research into the adverse effects of medications such as glucagon-like peptide 1 (GLP-1) receptor agonists.

4.
Cureus ; 15(5): e39478, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37378165

RESUMO

This case report describes an uncommon occurrence of myiasis, specifically a maggot-infected abscess, in a patient with reduced skin sensitivity resulting from severe burns. Myiasis is the infestation of live animal tissue by fly larvae, and while it is primarily associated with tropical and subtropical regions, cases acquired within the United States are rare. The presented case involves a 70-year-old male who arrived at the emergency department with an intensely painful, non-healing wound in the left elbow. Upon examination, the wound was found to be infested with numerous live maggots, and subsequent investigations revealed the larvae to be of the flesh fly species (Sarcophagidae). The patient's history of reduced skin sensitivity, previous burn injuries, and exposure to outdoor environments, coupled with poor hygiene and homelessness, likely contributed to the infestation. This report emphasizes the importance of considering myiasis caused by flesh fly larvae even in non-travel-related cases within the United States. Early recognition and prompt treatment are vital to preventing complications and secondary infections. Healthcare providers should remain vigilant in identifying and managing myiasis, and patients with decreased skin sensation should be educated about the need for regular skin surveillance and the utilization of preventive measures to mitigate potential infestations.

5.
Antioxidants (Basel) ; 12(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36829908

RESUMO

Median overall survival is very low in patients with glioblastoma (GBM), largely because these tumors become resistant to therapy. Recently, we found that a decrease in the cytosolic labile iron pool underlies the acquisition of radioresistance. Both cytosolic and mitochondrial iron are important for regulating ROS production, which largely facilitates tumor progression and response to therapy. Here, we investigated the role of the mitochondrial iron transporters mitoferrin-1 (MFRN1) and mitoferrin-2 (MFRN2) in GBM progression. Analysis of The Cancer Genome Atlas database revealed upregulation of MFRN1 mRNA and downregulation of MFRN2 mRNA in GBM tumor tissue compared with non-GBM tissue, yet only the tumor expression level of MFRN1 mRNA negatively correlated with overall survival in patients. Overexpression of MFRN1 in glioma cells significantly increased the level of mitochondrial iron, enhanced the proliferation rate and anchorage-independent growth of these cells, and significantly decreased mouse survival in an orthotopic model of glioma. Finally, MFRN1 overexpression stimulated the upregulation of glutathione, which protected glioma cells from 4-hydroxynonenal-induced protein damage. Overall, these results demonstrate a mechanistic link between MFRN1-mediated mitochondrial iron metabolism and GBM progression. Manipulation of MFRN1 may provide a new therapeutic strategy for improving clinical outcomes in patients with GBM.

6.
Cells ; 11(21)2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36359860

RESUMO

Iron is essential for many cellular processes, but cellular iron homeostasis must be maintained to ensure the balance of cellular signaling processes and prevent disease. Iron transport in and out of the cell and cellular organelles is crucial in this regard. The transport of iron into the mitochondria is particularly important, as heme and the majority of iron-sulfur clusters are synthesized in this organelle. Iron is also required for the production of mitochondrial complexes that contain these iron-sulfur clusters and heme. As the principal iron importers in the mitochondria of human cells, the mitoferrins have emerged as critical regulators of cytosolic and mitochondrial iron homeostasis. Here, we review the discovery and structure of the mitoferrins, as well as the significance of these proteins in maintaining cytosolic and mitochondrial iron homeostasis for the prevention of cancer and many other diseases.


Assuntos
Heme , Mitocôndrias , Humanos , Mitocôndrias/metabolismo , Homeostase , Heme/metabolismo , Ferro/metabolismo , Enxofre/metabolismo
7.
Metabolites ; 12(8)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36005623

RESUMO

Although often effective at treating newly diagnosed glioblastoma (GBM), increasing evidence suggests that chemo- and radiotherapy-induced alterations in tumor metabolism promote GBM recurrence and aggressiveness, as well as treatment resistance. Recent studies have demonstrated that alterations in glioma cell metabolism, induced by a switch in the isoform expression of cytochrome c oxidase subunit 4 (COX4), a key regulatory subunit of mammalian cytochrome c oxidase, could promote these effects. To understand how the two COX4 isoforms (COX4-1 and COX4-2) differentially affect glioma metabolism, glioma samples harvested from COX4-1- or COX4-2-overexpressing U251 cells were profiled using Gas chromatography-mass spectrometry GC-MS and Liquid Chromatography - Tandem Mass Spectrometry LC-MS/MS metabolomics platforms. The concentration of 362 metabolites differed significantly in the two cell types. The two most significantly upregulated pathways associated with COX4-1 overexpression were purine and glutathione metabolism; the two most significantly downregulated metabolic pathways associated with COX4-1 expression were glycolysis and fatty acid metabolism. Our study provides new insights into how Cytochrome c oxidase (CcO) regulatory subunits affect cellular metabolic networks in GBM and identifies potential targets that may be exploited for therapeutic benefit.

8.
Front Res Metr Anal ; 7: 897670, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755144

RESUMO

The underdevelopment of the higher education system in Guatemala and the fragility of its science and technology (S&T) contexts have compelled a significant number of talented Guatemalan scientists to be trained, educated, and employed abroad. The relocation of such skilled human power to different countries and regions has resulted in a growing Guatemalan Scientific Diaspora (GSD). Until recently, the emigration of scientists from the Global South to scientifically advanced countries in the North was studied as it negatively impacted the countries of origin. However, technological upgrades and globalization have progressively shifted the paradigm in which such scientific diasporas interact and connect, thus enabling them to influence their home countries positively. Due to the lack of knowledge-based evidence and functioning connecting platforms, the value and potential of the GSD in their involvement in proposing solutions to complex socio-economic, environmental, and other challenges faced by Guatemalan society remain unknown. Moreover, the lack of interaction of relevant stakeholders (S&T policy agents, international partners, higher education institutions and research centers, industry, and relevant not governmental organizations) represents a pervasive obstacle to the untapped impact of the GSD in the country. This study outlines the Guatemalan scientific diasporas' networking as a mechanism for building research excellence and intellectual capital. This force could respond to the need to strengthen the national science capacities and meet the demands for knowledge production and access to broader sectors of society. This research applied qualitative methodology that, through the conduction of focus group discussions and semi-structured interviews with members of the Guatemalan scientific community and relevant key stakeholders, delved into the existence and articulation of the GSD and potential stages for their engagement with their country of origin. Findings highlight the importance of digital and technological pathways that might leverage the GSD's knowledge and experience, channeling skills, and international connections for better interaction with the Guatemalan society. Furthermore, the discussion addresses how technology might turn brain drain into brain circulation, enabling the articulation of the GSD as a viable opportunity to generate collaboration between scientists abroad and local actors, ultimately impacting the building and development of Guatemalan science and national research capacities.

9.
Free Radic Biol Med ; 185: 25-35, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35476930

RESUMO

Radiotherapy is an important treatment modality for glioblastoma (GBM), yet the initial effectiveness of radiotherapy is eventually lost due to the development of adaptive radioresistance during fractionated radiation therapy. Defining the molecular mechanism(s) responsible for the adaptive radioresistance in GBM is necessary for the development of effective treatment options. The cellular labile iron pool (LIP) is very important for determining the cellular response to radiation, as it contributes to radiation-induced production of reactive oxygen species (ROS) such as lipid radicals through Fenton reactions. Recently, cytochrome c oxidase (CcO), a mitochondrial heme-containing enzyme also involved in regulating ROS production, was found to be involved in GBM chemoresistance. However, the role of LIP and CcO in GBM radioresistance is not known. Herein, we tested the hypothesis that CcO-mediated alterations in the level of labile iron contribute to adaptive radioresistance. Using an in vitro model of GBM adaptive radioresistance, we found an increase in CcO activity in radioresistant cells that associated with a decrease in the cellular LIP, decrease in lipid peroxidation, and a switch in the CcO subunit 4 (COX4) isoform expressed, from COX4-2 to COX4-1. Furthermore, knockdown of COX4-1 in radioresistant GBM cells decreased CcO activity and restored radiosensitivity, whereas overexpression of COX4-1 in radiosensitive cells increased CcO activity and rendered the cells radioresistant. Overexpression of COX4-1 in radiosensitive cells also significantly reduced the cellular LIP and lipid peroxidation. Pharmacological manipulation of the cellular labile iron level using iron chelators altered CcO activity and the radiation response. Overall, these results demonstrate a mechanistic link between CcO activity and LIP in GBM radioresistance and identify the CcO subunit isoform switch from COX4-2 to COX4-1 as a novel biochemical node for adaptive radioresistance of GBM. Manipulation of CcO and the LIP may restore the sensitivity to radiation in radioresistant GBM cells and thereby provide a strategy to improve therapeutic outcome in patients with GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Linhagem Celular Tumoral , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glioblastoma/genética , Glioblastoma/radioterapia , Humanos , Ferro , Tolerância a Radiação/genética , Espécies Reativas de Oxigênio
10.
Cell Stress ; 6(4): 45-60, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35478774

RESUMO

Glioblastoma (GBM) is a fatal disease with recurrences often associated with radioresistance. Although often effective at treating newly diagnosed GBM, increasing evidence suggests that radiotherapy-induced alterations in tumor metabolism promote GBM recurrence and aggressiveness. Using isogenic radiosensitive and radioresistant GBM cell lines and patient-derived xenolines, we found that acquired radioresistance is associated with a shift from a glycolytic metabolism to a more oxidative metabolism marked by a substantial increase in the activity of the mitochondrial respiratory chain complex cytochrome c oxidase (CcO). This elevated CcO activity was associated with a switch in the isoform expression of the CcO regulatory subunit COX4, from COX4-2 to COX4-1, assembly of CcO-containing mitochondrial supercomplexes (SCs), and reduced superoxide (O2 •-) production. Overexpression of COX4-1 in the radiosensitive cells was sufficient to promote the switch from glycolytic to oxidative metabolism and the incorporation of CcO into SCs, with a concomitant reduction in O2 •- production. Conversely, silencing of COX4-1 expression in normally radioresistant cells reduced CcO activity, promoted the disassembly of mitochondrial SCs, and increased O2 •- production. Additionally, gain or loss of COX4-1 expression was sufficient to induce the radioresistant or radiosensitive phenotype, respectively. Our results demonstrate that COX4-1 promotes SC assembly in GBM cells, and SC assembly may in turn regulate the production of reactive oxygen species and thus the acquisition of radioresistance in GBM.

11.
Bioconjug Chem ; 33(11): 1957-1972, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-35041398

RESUMO

Glioblastoma multiforme (GBM) is the most malignant type of brain tumor and has an extremely poor prognosis. Current treatment protocols lack favorable outcomes, and alternative treatments with superior efficacy are needed. In this study, we demonstrate that loading paclitaxel (PTX) in a polymeric, nanoparticulate delivery system is capable of improving its brain accumulation and therapeutic activity. We independently incorporated two different positively charged surface modifiers, poly(amidoamine) (PAMAM) and poly(ethylenimine) (PEI), onto poly(lactic-co-glycolic acid) (PLGA)-polyethylene glycol (PEG), PLGA-PEG, nanoparticles (NPs) using a modified nanoprecipitation technique that assures the formation of nanosized particles while exposing the positively charged polymer on the surface. The prepared NPs underwent comprehensive analyses of their size, charge, in vitro permeability against a BBB cell line, and in vivo biodistribution. Our results demonstrated the successful fabrication of positively charged NPs using PAMAM or PEI. Importantly, significant improvement in brain accumulation (in vivo) was associated with NPs containing PAMAM compared to unmodified NPs or NPs containing PEI. Finally, the efficacy of PAMAM-modified NPs loaded with PTX was evaluated with orthotopic human GBM xenografts in a mouse model, and the data demonstrated improved survival and equivalent safety compared to soluble PTX. Our data substantiate the importance of surface chemistry on the magnitude of NP accumulation in the brain and pave the way for further in vivo evaluation of chemotherapeutic drugs against GBM that have previously been overlooked because of their limited ability to cross the BBB.


Assuntos
Glioblastoma , Nanopartículas , Humanos , Animais , Camundongos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/uso terapêutico , Distribuição Tecidual , Ácido Láctico , Modelos Animais de Doenças , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Polietilenoglicóis/uso terapêutico , Encéfalo/patologia , Portadores de Fármacos/uso terapêutico
12.
Neurooncol Adv ; 4(1): vdab186, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35088051

RESUMO

BACKGROUND: Glioblastoma (GBM) has a 5-year survival rate of 3%-5%. GBM treatment includes maximal resection followed by radiotherapy with concomitant and adjuvant temozolomide (TMZ). Cytochrome C oxidase (CcO) is a mitochondrial enzyme involved in the mechanism of resistance to TMZ. In a prior retrospective trial, CcO activity in GBMs inversely correlated with clinical outcome. The current Cyto-C study was designed to prospectively evaluate and validate the prognostic value of tumor CcO activity in patients with newly diagnosed primary GBM, and compared to the known prognostic value of MGMT promoter methylation status. METHODS: This multi-institutional, blinded, prospective biomarker study enrolled 152 patients with newly diagnosed GBM who were to undergo surgical resection and would be candidates for standard of care. The primary end point was overall survival (OS) time, and the secondary end point was progression-free survival (PFS) time. Tumor CcO activity and MGMT promoter methylation status were assayed in a centralized laboratory. RESULTS: OS and PFS did not differ by high or low tumor CcO activity, and the prognostic validity of MGMT promoter methylation was confirmed. Notably, a planned exploratory analysis suggested that the combination of low CcO activity and MGMT promoter methylation in tumors may be predictive of long-term survival. CONCLUSIONS: Tumor CcO activity alone was not confirmed as a prognostic marker in GBM patients. However, the combination of low CcO activity and methylated MGMT promoter may reveal a subgroup of GBM patients with improved long-term survival that warrants further evaluation. Our work also demonstrates the importance of performing large, multi-institutional, prospective studies to validate biomarkers. We also discuss lessons learned in assembling such studies.

13.
Cienc. tecnol. salud ; 9(1): 6-18, 2022. il 27
Artigo em Espanhol | LILACS, DIGIUSAC, LIGCSA | ID: biblio-1382357

RESUMO

La deposición de nutrientes por vía atmosférica tiene graves impactos sobre la ecología de bosques y cuerpos de agua templados. Sin embargo, su importancia en cuerpos de agua neotropicales casi no ha sido estudiada. En este artículo se cuantifica la contribución de nitrógeno inorgánico disuelto (NID, [NO3--N + NH4+-N]) y fósforo inorgánico soluble (FIS, [PO4-3-P]) depositados en bulto sobre superficies húmedas por vía atmosférica hacia el lago Atitlán (Guatemala). Las cargas estimadas de NID y FIS consecuencia de la deposición atmosférica directa (depositada sobre la superficie del lago) fueron de 151.2 ton/año y 5.6 ton/año, respectivamente. Con estos resulta-dos, se estima que el aporte de FIS por deposición atmosférica al lago Atitlán es comparable al de sus principales ríos tributarios, y de casi el doble para el ingreso de NID. Las estimaciones para el lago Atitlán son mayores que lo reportado para otros lagos. Nuestro estudio proporciona información básica para entender la eutrofización del lago Atitlán, enfatizado en la importancia de la deposición atmosférica como contribuyente al deterioro de este cuerpo de agua. Además, demuestra la necesidad de extender este tipo de estudio a otras cuencas neotropicales y la importancia de minimizar este impacto.


Atmospheric nutrient deposition has serious impacts on the ecology of forests and temperate water bodies nevertheless its importance in Neotropical water bodies has hardly been studied. Here we quantify the contribution of bulk atmospheric deposition on wet surfaces of dissolved inorganic nitrogen (DIN,[NO3--N + NH4+-N])and soluble inorganic phosphorus (SIP, [PO4-3-P])into Lake Atitlán (Guatemala). The estimated NID and SIP loads from this direct deposition on the lake surface were respectively, 151.2 tons/year and 5.6 tons/year. With these results, we estimated that the SIP input from atmospheric deposition to Lake Atitlán is comparable to that from the lake's main tributary rivers, whereas for DIN entry this is almost twice as much. Estimates for Lake Atitlán are higher than those reported for many lakes. Our study provides basic information towards understanding the eutrophication of Lake Atitlán, emphasizes the importance of atmospheric deposition in this process and the need for additional studies to document the process in neotropical watersheds.


Assuntos
Humanos , Fósforo/análise , Lagos/análise , Nitrogênio/análise , Chuva/química , Temperatura , Vento , Bacias , Nutrientes , Eutrofização
14.
Antioxidants (Basel) ; 10(12)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34943091

RESUMO

Glioblastoma remains the deadliest form of brain cancer, largely because these tumors become resistant to standard of care treatment with radiation and chemotherapy. Intracellular production of reactive oxygen species (ROS) is necessary for chemo- and radiotherapy-induced cytotoxicity. Here, we assessed whether antioxidant catalase (CAT) affects glioma cell sensitivity to temozolomide and radiation. Using The Cancer Genome Atlas database, we found that CAT mRNA expression is upregulated in glioma tumor tissue compared with non-tumor tissue, and the level of expression negatively correlates with the overall survival of patients with high-grade glioma. In U251 glioma cells, CAT overexpression substantially decreased the basal level of hydrogen peroxide, enhanced anchorage-independent cell growth, and facilitated resistance to the chemotherapeutic drug temozolomide and ionizing radiation. Importantly, pharmacological inhibition of CAT activity reduced the proliferation of glioma cells isolated from patient biopsy samples. Moreover, U251 cells overexpressing CAT formed neurospheres in neurobasal medium, whereas control cells did not, suggesting that the radio- and chemoresistance conferred by CAT may be due in part to the enrichment of glioma stem cell populations. Finally, CAT overexpression significantly decreased survival in an orthotopic mouse model of glioma. These results demonstrate that CAT regulates chemo- and radioresistance in human glioma.

15.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34810262

RESUMO

Human-induced deforestation and soil erosion were environmental stressors for the ancient Maya of Mesoamerica. Furthermore, intense, periodic droughts during the Terminal Classic Period, ca. Common Era 830 to 950, have been documented from lake sediment cores and speleothems. Today, lakes worldwide that are surrounded by dense human settlement and intense riparian land use often develop algae/cyanobacteria blooms that can compromise water quality by depleting oxygen and producing toxins. Such environmental impacts have rarely been explored in the context of ancient Maya settlement. We measured nutrients, biomarkers for cyanobacteria, and the cyanotoxin microcystin in a sediment core from Lake Amatitlán, highland Guatemala, which spans the last ∼2,100 y. The lake is currently hypereutrophic and characterized by high cyanotoxin concentrations from persistent blooms of the cyanobacterium Microcystis aeruginosa Our paleolimnological data show that harmful cyanobacteria blooms and cyanotoxin production occurred during periods of ancient Maya occupation. Highest prehistoric concentrations of cyanotoxins in the sediment coincided with alterations of the water system in the Maya city of Kaminaljuyú, and changes in nutrient stoichiometry and maximum cyanobacteria abundance were coeval with times of greatest ancient human populations in the watershed. These prehistoric episodes of cyanobacteria proliferation and cyanotoxin production rivaled modern conditions in the lake, with respect to both bloom magnitude and toxicity. This suggests that pre-Columbian Maya occupation of the Lake Amatitlán watershed negatively impacted water potability. Prehistoric cultural eutrophication indicates that human-driven nutrient enrichment of water bodies is not an exclusively modern phenomenon and may well have been a stressor for the ancient Maya.


Assuntos
Toxinas de Cianobactérias , Proliferação Nociva de Algas , Atividades Humanas/história , Lagos/microbiologia , Cianobactérias , Monitoramento Ambiental , Geografia , Guatemala , História Antiga , Humanos , Microcistinas , Microcystis , Datação Radiométrica , Qualidade da Água
16.
Children (Basel) ; 8(8)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34438528

RESUMO

BACKGROUND: Malformations of cortical development (MCD) include a wide range of congenital disorders mostly causing severe cognitive dysfunction and epilepsy. OBJECTIVE: to report on clinical features including cognitive involvement, epileptic seizures with response to antiseizure medications, comorbidities in young patients affected by MCD and followed in a single tertiary hospital. PATIENTS AND METHODS: A retrospective review of the medical records and magnetic resonance images (MRI) of 19 young patients with an age ranging between eight days and fifteen years affected by MCD and admitted to Pediatrics Department University of Catania, Italy from October 2009 and October 2020 were selected. Patients were distinguished in three groups following the Barcovich et al. 2012 classification for MCD: 4 (21%) in Group I; 8 (42%) in Group II; and, and 7 (37%) in Group III. Clinical features and MRI of the patients including cognitive involvement, epilepsy type and response to drugs treatment were analyzed. RESULTS: In Group I, two patients showed cortical dysplasia and two dysembryoplastic neuroepithelial tumors plus focal cortical dysplasia; developmental delay/intellectual disability (DD/ID) was severe in one, moderate in one and absent in two; the type of seizures was in all the cases focal to bilateral tonic-clonic (FBTCs), and drug resistant was found in one case. In Group II, three patients showed neuronal hetero-topias and five had pachygyria-lissencephaly: DD/ID was severe in four, moderate in two, and absent in two; the type of seizure was focal (FS) in five, focal to bilateral tonic-clonic (FBTCs) in two, infantile spasms (IS) in one, and drug resistant was found in three. In Group III, six showed polymicrogyria and one schizencephaly: DD/ID was found severe in five, moderate in two, and the type of seizure was focal (FS) in five, FBTCS in two, and drug resistance was found in three.

17.
J Integr Neurosci ; 20(2): 509-513, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34258953

RESUMO

A short review on the clinical presentation of pediatrics cases of Bickerstaff brain encephalitis emphasizing the broad clinical spectrum of the disease. Cases of pediatric Bickerstaff's brainstem encephalitis collected on three electronic medical databases (PubMed, Cochrane Library and Scopus Web of Science) are reviewed. The inclusion criteria of the cases were based on the clinical characteristics of the disorder in the pediatric age. We reviewed 20 articles on Bickerstaff's brainstem encephalitis, identifying 40 pediatric cases focused on the clinical symptoms. We saw that the prevalence was higher in male subjects, and the median age at diagnosis was 8 years. The phenotype of pediatrics patients was similar to previously published literature. We identify three cases of overlapping forms between Bickerstaff brain encephalitis and Guillain-Barré Syndrome in patients with lower limbs weakness and typical signs of Bickerstaff brain encephalitis, suggesting a combined involvement of the central and peripheral nervous system. Although there is no defined data on incidence and prevalence in the literature, Bickerstaff's brainstem encephalitis appears to be a rare disorder, especially in children. The incidence of Bickerstaff brain encephalitis and Guillain-Barré Syndrome, and Miller Fisher Syndrome has been underrated in the past, primarily due to an underestimation of the forms with a Peripheral Nervous System involvement. Bickerstaff brain encephalitis usually has a rapid and acute onset within 2-4 weeks, characterized by a typical picture of ophthalmoplegia, hyperreflexia, cerebellar symptoms as ataxia. The subsequent manifestations of hyperreflexia or consciousness disturbances as drowsiness, sleepiness, or coma, indicative of central involvement, suggest a Bickerstaff brain encephalitis clinical diagnosis.


Assuntos
Doenças Autoimunes do Sistema Nervoso/fisiopatologia , Tronco Encefálico/fisiopatologia , Doenças Autoimunes do Sistema Nervoso/epidemiologia , Criança , Encefalite/epidemiologia , Encefalite/fisiopatologia , Humanos
18.
Sci Rep ; 11(1): 13848, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226571

RESUMO

Metagenomic and traditional paleolimnological approaches are suitable to infer past biological and environmental changes, however, they are often applied independently, especially in tropical regions. We combined both approaches to investigate Holocene Prokaryote and Eukaryote diversity and microbial metabolic pathways in ancient Lake Chalco, Mexico. Here, we report on diversity among a large number of lineages (36,722 OTUs) and functional diversity (27,636,243 non-clustered predicted proteins, and 6,144 annotated protein-family genes). The most abundant domain is Bacteria (81%), followed by Archaea (15%) and Eukarya (3%). We also determined the diversity of protein families and their relationship to metabolic pathways. The early Holocene (> 11,000 cal years BP) lake was characterized by cool, freshwater conditions, which later became warmer and hyposaline (11,000-6,000 cal years BP). We found high abundances of cyanobacteria, and fungi groups associated with mature forests in these sediments. Bacteria and Archaea include mainly anaerobes and extremophiles that are involved in the sulfur, nitrogen, and carbon cycles. We found evidence for early human impacts, including landscape modifications and lake eutrophication, which began ~ 6,000 cal years BP. Subsaline, temperate conditions were inferred for the past 5,000 years. Finally, we found nitrogen-fixing bacteria and protein-family genes that are linked to contaminated environments, as well as several fungal pathogens of crops in near-surface sediments.


Assuntos
Archaea/genética , Bactérias/genética , Lagos/microbiologia , Microbiota/genética , Ciclo do Carbono/genética , Sedimentos Geológicos/microbiologia , Humanos , Metagenoma/genética , México , Nitrogênio/metabolismo , Filogenia , Clima Tropical
19.
Cancers (Basel) ; 12(9)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899427

RESUMO

Ionizing radiation is a common and effective therapeutic option for the treatment of glioblastoma (GBM). Unfortunately, some GBMs are relatively radioresistant and patients have worse outcomes after radiation treatment. The mechanisms underlying intrinsic radioresistance in GBM has been rigorously investigated over the past several years, but the complex interaction of the cellular molecules and signaling pathways involved in radioresistance remains incompletely defined. A clinically effective radiosensitizer that overcomes radioresistance has yet to be identified. In this review, we discuss the current status of radiation treatment in GBM, including advances in imaging techniques that have facilitated more accurate diagnosis, and the identified mechanisms of GBM radioresistance. In addition, we provide a summary of the candidate GBM radiosensitizers being investigated, including an update of subjects enrolled in clinical trials. Overall, this review highlights the importance of understanding the mechanisms of GBM radioresistance to facilitate the development of effective radiosensitizers.

20.
Cell Stress ; 3(2): 47-65, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31225500

RESUMO

Glioblastoma, also known as glioblastoma multi-forme, is the most common and deadliest form of high-grade malignant brain tumors with limited available treatments. Within the glioblastoma tumor microenvironment (TME), tumor cells, stromal cells, and infiltrating immune cells continuously interact and exchange signals through various secreted factors including cytokines, chemokines, growth factors, and metabolites. Simultaneously, they dynamically reprogram their metabolism according to environmental energy demands such as hypoxia and neo-vascularization. Such metabolic re-programming can determine fates and functions of tumor cells as well as immune cells. Ultimately, glioma cells in the TME transform immune cells to suppress anti-tumor immune cells such as T, natural killer (NK) cells, and dendritic cells (DC), and evade immune surveillance, and even to promote angiogenesis and tumor metastasis. Glioma-associated microglia/macrophages (GAMM) and myeloid-derived suppressor cells (MDSC) are most abundantly recruited and expanded myeloid lineage cells in glioblastoma TME and mainly lead to immunosuppression. In this review, of myeloid cells we will focus on MDSC as an important driver to induce immunosuppression in glioblastoma. Here, we review current literature on immunosuppressive functions and metabolic reprogramming of MDSCs in glioblastoma and discuss their metabolic pathways as potential therapeutic targets to improve current incurable glioblastoma treatment.

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