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1.
J Chem Inf Model ; 64(8): 3350-3359, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38566451

RESUMO

The B domain of protein A (BdpA), a small three-helix bundle, folds on a time scale of a few microseconds with heterogeneous native and unfolded states. It is widely used as a model for understanding protein folding mechanisms. In this work, we use structure-based models (SBMs) and atomistic simulations to comprehensively investigate how BdpA folding is associated with the formation of its secondary structure. The energy landscape visualization method (ELViM) was used to characterize the pathways that connect the folded and unfolded states of BdpA as well as the sets of structures displaying specific ellipticity patterns. We show that the native state conformational diversity is due mainly to the conformational variability of helix I. Helices I, II, and III occur in a weakly correlated manner, with Spearman's rank correlation coefficients of 0.1539 (I and II), 0.1259 (I and III), and 0.2561 (II and III). These results, therefore, suggest the highest cooperativity between helices II and III. Our results allow the clustering of partially folded structures of folding of the B domain of protein A on the basis of its secondary structure, paving the way to an understanding of environmental factors in the relative stability of the basins of the folding ensemble, which are illustrated by the structural dependency of the protein hydration structures, as computed with minimum-distance distribution functions.


Assuntos
Simulação de Dinâmica Molecular , Domínios Proteicos , Dobramento de Proteína , Proteína Estafilocócica A , Água , Água/química , Proteína Estafilocócica A/química , Proteína Estafilocócica A/metabolismo , Conformação Proteica em alfa-Hélice , Modelos Moleculares , Termodinâmica
3.
Acta Trop ; 252: 107143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38331084

RESUMO

Leishmaniasis is an endemic disease in more than 90 countries, constituting a relevant public health problem. Limited treatment options, increase in resistance, and therapeutic failure are important aspects for the discovery of new treatment options. Drug repurposing may accelerate the discovery of antiLeishmanial drugs. Recent tests indicating the in vitro potential of antimalarials Leishmania resulted in the design of this study. This study aimed at evaluating the susceptibility of Leishmania (L.) amazonensis to chloroquine (CQ) and quinine (QN), alone or in combination with amphotericin B (AFT) and pentamidine (PTN). In the in vitro tests, first, we evaluated the growth inhibition of 50 % of promastigotes (IC50) and cytotoxicity for HepG2 and THP-1 cells (CC50). The IC50 values of AFT and PNT were below 1 µM, while the IC50 values of CQ and QN ranged between 4 and 13 µM. Concerning cytotoxicity, CC50 values ranged between 7 and 30 µM for AFT and PNT, and between 22 and 157 µM for the antimalarials. We also calculated the Selectivity Index (SI), where AFT and PTN obtained the highest values, while the antimalarias obtained values between 5 and 12. Both antimalarials were additive (Æ©FIC 1.05-1.8) in combination with AFT and PTN. For anti-amastigote activity, the drugs obtained the following ICA50 values: AFT (0.26 µM), PNT (2.09 µM), CQ (3.77 µM) and QN (24.5 µM). In the in vivo tests, we observed that the effective dose for the death of 50 % of parasites (ED50) of AFT and CQ were 0.63 mg/kg and 27.29 mg/kg, respectively. When combining CQ with AFT, a decrease in parasitemia was observed, being statistically equal to the naive group. For cytokine quantification, it was observed that CQ, despite presenting anti-inflammatory activity was effective at increasing the production of IFN-γ. Overall, our data indicate that chloroquine will probably be a candidate for repurposing and use in drug combination therapy.


Assuntos
Antimaláricos , Leishmania , Leishmaniose , Humanos , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Quinina/farmacologia , Quinina/uso terapêutico , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Leishmaniose/tratamento farmacológico , Plasmodium falciparum
4.
Br J Pharmacol ; 181(2): 273-282, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37309573

RESUMO

Although chemotherapeutic regimens can eliminate blasts in leukaemia patients, such therapies are associated with toxicity and often fail to eliminate all malignant cells resulting in disease relapse. Disease relapse has been attributed to the persistence of leukaemia cells in the bone marrow (BM) with the capacity to recapitulate disease; these cells are often referred to as leukaemia stem cells (LSCs). Although LSCs have distinct characteristics in terms of pathobiology and immunophenotype, they are still regulated by their interactions with the surrounding microenvironment. Thus, understanding the interaction between LSCs and their microenvironment is critical to identify effective therapies. To this end, there are numerous efforts to develop models to study such interactions. In this review, we will focus on the reciprocal interactions between LSCs and their milieu in the BM. Furthermore, we will highlight relevant therapies targeting these interactions and discuss some of the promising in vitro models designed to mimic such relationship. LINKED ARTICLES: This article is part of a themed issue on Cancer Microenvironment and Pharmacological Interventions. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.2/issuetoc.


Assuntos
Leucemia , Recidiva Local de Neoplasia , Humanos , Células-Tronco , Recidiva , Microambiente Tumoral
5.
3 Biotech ; 13(12): 405, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37987025

RESUMO

Gametocytes are the forms of the malaria parasite that are essential for the continuation of the transmission cycle to the vector Anopheles. This study aimed to evaluate the parasite density of Plasmodium spp gametocytes in samples from patients in the region of Porto Velho, Rondônia. Slides containing patient samples were selected from users who sought out care at the Center for Research in Tropical Medicine (CEPEM) during the period from January to December 2016. Samples of Plasmodium vivax and Plasmodium falciparum were selected for analysis of their respective gametocytes. In parallel, monitoring was performed in cultures of NF54 strain P. falciparum gametocytes. Of 248 thick smear slides (EG) evaluated in double blind, 142 (57.2%) were detected with P. vivax, of this total 47 (18.9%) had gametocytes, 1 (0.4%) with LVC negative diagnosis for gametocytes and 1 (0.4%) Pv + Pf (mixed malaria). Regarding P. falciparum, the total number of samples analyzed was 106 (42.7%), of which 20 (8.0%) had gametocytes detected, 6 (2.4%) LVC negative for gametocyte forms, and 3 (1.2%) Pv + Pf (mixed malaria), Plasmodium malariae species was not detected among the samples. The results showed that P. vivax gametocytes were present in the first days of symptoms, with a higher prevalence in patients with two crosses, a fact that was also observed in patients with P. falciparum regarding the prevalence of gametocytes. Faced with this problem, it is necessary to monitor the fluctuation of gametocytes, since these forms are responsible for continuing the malaria cycle within the mosquito vector.

6.
Sci Rep ; 13(1): 18207, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875508

RESUMO

Obtaining Plasmodium vivax sporozoites is essential for in vitro culture of liver stage parasites, not only to understand fundamental aspects of parasite biology, but also for drug and vaccine development. A major impediment to establish high-throughput in vitro P. vivax liver stage assays for drug development is obtaining sufficient numbers of sporozoites. To do so, female anopheline mosquitoes have to be fed on blood from P. vivax-infected patients through an artificial membrane-feeding system, which in turns requires a well-established Anopheles colony. In this study we established conditions to provide a robust supply of P. vivax sporozoites. Adding a combination of serum replacement and antibiotics to the membrane-feeding protocol was found to best improve sporozoite production. A simple centrifugation method appears to be a possible tool for rapidly obtaining purified sporozoites with a minimal loss of yield. However, this method needs to be better defined since sporozoite viability and hepatocyte infection were not evaluated.


Assuntos
Anopheles , Malária Vivax , Animais , Humanos , Feminino , Plasmodium vivax , Anopheles/parasitologia , Malária Vivax/parasitologia , Esporozoítos , Hepatócitos
7.
Front Cell Dev Biol ; 11: 1250869, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719885

RESUMO

Introduction: Bone metastasis is one of the causes that mainly decrease survival in patients with advanced breast cancer. Therefore, it is essential to find prognostic markers for the occurrence of this type of metastasis during the early stage of the disease. Currently, cancer-associated fibroblasts, which represent 80% of the fibroblasts present in the tumor microenvironment, are an interesting target for studying new biomarkers and developing alternative therapies. This study evaluated the prognostic significance of the CD105 expression in cancer-associated fibroblasts in early breast cancer patients. Methods: Immunohistochemistry was used to assess CD105 expression in invasive ductal breast carcinomas (n = 342), analyzing its association with clinical and pathological characteristics. Results: High CD105 expression in cancer-associated fibroblasts was associated with an increased risk of metastatic occurrence (p = 0.0003), particularly bone metastasis (p = 0.0005). Furthermore, high CD105 expression was associated with shorter metastasis-free survival, bone metastasis-free survival, and overall survival (p = 0.0002, 0.0006, and 0.0002, respectively). CD105 expression also constituted an independent prognostic factor for metastasis-free survival, bone metastasis-free survival, and overall survival (p = 0.0003, 0.0006, and 0.0001, respectively). Discussion: The high CD105 expression in cancer-associated fibroblasts is an independent prognostic marker for bone metastasis in early breast cancer patients. Therefore, the evaluation of CD105(+) CAFs could be crucial to stratify BCPs based on their individual risk profile for the development of BM, enhancing treatment strategies and outcomes.

9.
Oncol Res ; 31(3): 361-374, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37305388

RESUMO

Breast cancer is the predominant form of carcinoma among women worldwide, with 70% of advanced patients developing bone metastases, with a high mortality rate. In this sense, the bone marrow (BM) mesenchymal stem/stromal cells (MSCs) are critical for BM/bone homeostasis, and failures in their functionality, transform the BM into a pre-metastatic niche (PMN). We previously found that BM-MSCs from advanced breast cancer patients (BCPs, infiltrative ductal carcinoma, stage III-B) have an abnormal profile. This work aims to study some of the metabolic and molecular mechanisms underlying MSCs shift from a normal to an abnormal profile in this group of patients. A comparative analysis was undertaken, which included self-renewal capacity, morphology, proliferation capacity, cell cycle, reactive oxygen species (ROS) levels, and senescence-associated ß­galactosidase (SA­ß­gal) staining of BM-derived MSCs isolated from 14 BCPs and 9 healthy volunteers (HVs). Additionally, the expression and activity of the telomerase subunit TERT, as well as telomere length, were measured. Expression levels of pluripotency, osteogenic, and osteoclastogenic genes (OCT-4, SOX-2, M-CAM, RUNX-2, BMP-2, CCL-2, M-CSF, and IL-6) were also determined. The results showed that MSCs from BCPs had reduced ,self-renewal and proliferation capacity. These cells also exhibited inhibited cell cycle progression and phenotypic changes, such as an enlarged and flattened appearance. Additionally, there was an increase in ROS and senescence levels and a decrease in the functional capacity of TERT to preserve telomere length. We also found an increase in pro-inflammatory/pro-osteoclastogenic gene expression and a decrease in pluripotency gene expression. We conclude that these changes could be responsible for the abnormal functional profile that MSCs show in this group of patients.


Assuntos
Neoplasias da Mama , Carcinoma , Células-Tronco Mesenquimais , Humanos , Feminino , Medula Óssea , Neoplasias da Mama/genética , Espécies Reativas de Oxigênio
10.
PLoS Negl Trop Dis ; 17(6): e0011425, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37327209

RESUMO

Malaria is caused by parasite of the genus Plasmodium and is still one of the most important infectious diseases in the world. Several biological characteristics of Plasmodium vivax contribute to the resilience of this species, including early gametocyte production, both of which lead to efficient malaria transmission to mosquitoes. This study evaluated the impact of currently used drugs on the transmission of P. vivax. Participants received one of the following treatments for malaria: i) chloroquine [10 mg/kg on day 1 and 7.5 mg/kg on day 2 and 3] co-administered with Primaquine [0.5 mg/kg/day for 7 days]; ii) Chloroquine [10 mg/kg on day 1 and 7.5 mg/kg on day 2 and 3] co-administered with one-dose of Tafenoquine [300 mg on day 1]; and iii) Artesunate and Mefloquine [100 mg and 200 mg on day 1, 2 and 3] co-administered with Primaquine [0.5 mg/kg/day for 14 days]. Patient blood was collected before treatment and 4 h, 24 h, 48 h and 72 h after treatment. The blood was used to perform a direct membrane feeding assay (DMFA) using Anopheles darlingi mosquitoes. The results showed 100% inhibition of the mosquito infection after 4 h using ASMQ+PQ, after 24 h for the combination of CQ+PQ and 48 h using CQ+TQ. The density of gametocytes declined over time in all treatment groups, although the decline was more rapid in the ASMQ+PQ group. In conclusion, it was possible to demonstrate the transmission-blocking efficacy of the malaria vivax treatment and that ASMQ+PQ acts faster than the two other treatments.


Assuntos
Anopheles , Antimaláricos , Malária Vivax , Malária , Animais , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Primaquina/farmacologia , Primaquina/uso terapêutico , Malária Vivax/tratamento farmacológico , Malária Vivax/parasitologia , Anopheles/parasitologia , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Malária/tratamento farmacológico , Plasmodium vivax
11.
Front Oncol ; 13: 1073793, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36890825

RESUMO

Introduction: Osteolytic bone metastasis in advanced breast cancer stages are a major complication for patient´s quality life and a sign of low survival prognosis. Permissive microenvironments which allow cancer cell secondary homing and later proliferation are fundamental for metastatic processes. The causes and mechanisms behind bone metastasis in breast cancer patients are still an unsolved puzzle. Therefore, in this work we contribute to describe bone marrow pre-metastatic niche in advanced breast cancer patients. Results: We show an increase in osteoclasts precursors with a concomitant imbalance towards spontaneous osteoclastogenesis which can be evidenced at bone marrow and peripheral levels. Pro-osteoclastogenic factors RANKL and CCL-2 may contribute to bone resorption signature observed in bone marrow. Meanwhile, expression levels of specific microRNAs in primary breast tumors may already indicate a pro-osteoclastogenic scenario prior to bone metastasis. Discussion: The discovery of prognostic biomarkers and novel therapeutic targets linked to bone metastasis initiation and development are a promising perspective for preventive treatments and metastasis management in advanced breast cancer patients.

12.
Rev. esp. med. prev. salud pública ; 28(1): 8-16, 2023. tab
Artigo em Espanhol | IBECS | ID: ibc-221435

RESUMO

Objetivo: La literatura sobre la vacunación de personas que pueden transmitir la gripe a enfermos con alta probabilidad de presentar complicaciones se suele centrar en sanitarios y la de sus convivientes ha sido abordada con escasa frecuencia. Los objetivos fueron estimar la proporción de individuos vulnerables conocedores de la indicación de vacunación antigripal de su entorno y explorar los factores asociados con la inmunización de sus convivientes. Materiales y métodos: Estudio de base individual, observacional, transversal y descriptivo, mediante encuesta. Fueron seleccionados todos los pacientes del grupo 7 de la Estrategia de vacunación COVID-19, citados en el Hospital General de Requena para la administración de la dosis de refuerzo en abril de 2022. La encuesta recogió información del paciente y sus convivientes. El análisis se organizó en una fase descriptiva y otra analítica. Resultados: La muestra final fue de 131 pacientes y 191 convivientes. Solo 29 (22,1%) pacientes conocían la indicación de vacunación de su entorno. De los convivientes únicamente 78 (40,9%) se habían vacunado de la gripe en la campaña 2021-22. Que el paciente se vacunara (odds ratio -OR- 26,2), que conociera la indicación de vacunar a su entorno (OR 5,4), que el conviviente tuviera indicación propia de vacunación (OR 8,6) y su edad (OR 1,1) aumentaron independientemente la probabilidad de vacunación de sus convivientes. Conclusiones: La vacunación antigripal de los convivientes de pacientes de alto riesgo fue escasamente conocida y la implantación de estrategias informativas breves podría paliar esta situación.(AU)


Objective: Research on vaccination of those who can transmit influenza to patients with a high probability of presenting complications has been usually focused on health care workers and the issue of the immunization of their household has been rarely addressed. The aims were to estimate the proportion of vulnerable individuals aware of the indication for influenza vaccination in their household and to explore the factors associated with the immunization of their relatives.Methodology: An observational, cross-sectional, descriptive, survey was performed. All patients belonging to group 7 of the COVID-19 vaccination strategy, who were scheduled in April 2022 at the General Hospital of Requena for a booster dose of SARS-CoV-2 vaccine injection were selected. Information about the patient profile and their household was gathered. Analysis followed two, descriptive and analytical, phases. Results: TA sample of 131 patients and 191 relatives met the selection criteria. Only 29 (22.1%) patients knew the indication for household vaccination. Of their relatives, only 78 (40.9%) had been vaccinated against influenza in the 2021-22 campaign. Whether the patient had been vaccinated (odds ratio -OR- 26.2), whether the patient was aware of the indication to vaccinate his or her family (OR 5.4), whether the relative had an own indication for vaccination (OR 8.6) and their age (OR 1.1) independently increased the probability of vaccination of their household. Discussion: The convenience of the influenza vaccination of those living with high-risk patients was poorly known and the implementation of brief informative strategies could improve this situation.(AU)


Assuntos
Humanos , Masculino , Feminino , Vacinação , Influenza Humana/prevenção & controle , Vacinas contra Influenza , Programas de Imunização , Hospedeiro Imunocomprometido , Família , Estudos Transversais , Epidemiologia Descritiva , Inquéritos e Questionários , Fatores de Risco , Medicina Preventiva , Serviços Preventivos de Saúde
13.
Front Oncol, v. 13, 1073793, fev. 2023
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4823

RESUMO

Introduction: Osteolytic bone metastasis in advanced breast cancer stages are a major complication for patient´s quality life and a sign of low survival prognosis. Permissive microenvironments which allow cancer cell secondary homing and later proliferation are fundamental for metastatic processes. The causes and mechanisms behind bone metastasis in breast cancer patients are still an unsolved puzzle. Therefore, in this work we contribute to describe bone marrow pre-metastatic niche in advanced breast cancer patients. Results: We show an increase in osteoclasts precursors with a concomitant imbalance towards spontaneous osteoclastogenesis which can be evidenced at bone marrow and peripheral levels. Pro-osteoclastogenic factors RANKL and CCL-2 may contribute to bone resorption signature observed in bone marrow. Meanwhile, expression levels of specific microRNAs in primary breast tumors may already indicate a pro-osteoclastogenic scenario prior to bone metastasis. Discussion: The discovery of prognostic biomarkers and novel therapeutic targets linked to bone metastasis initiation and development are a promising perspective for preventive treatments and metastasis management in advanced breast cancer patients.

14.
Malar J ; 21(1): 163, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658964

RESUMO

BACKGROUND: The colonization of mosquitoes susceptible to Plasmodium vivax via direct membrane feeding assay (DMFA) has the potential to significantly advance our knowledge of P. vivax biology, vector-parasite interaction and transmission-blocking vaccine research. Anopheles darlingi and Anopheles deaneorum are important vectors of malaria in the Western Brazilian Amazon. Since 2018, well-established colonies of these species have been maintained in order to mass produce mosquitoes destined for P. vivax infection. Plasmodium susceptibility was confirmed when the colonies were established, but susceptibility needs to be maintained for these colonies to remain good models for pathogen transmission. Thus, the susceptibility was assessed of colonized mosquitoes to P. vivax isolates circulating in the Western Amazon. METHODS: Laboratory-reared mosquitoes from F10-F25 generations were fed on P. vivax blood isolates via DMFA. Susceptibility was determined by prevalence and intensity of infection as represented by oocyst load seven days after blood feeding, and sporozoite load 14 days after blood feeding. The effect of infection on mosquito survival was evaluated from initial blood feeding until sporogonic development and survival rates were compared between mosquitoes fed on infected and uninfected blood. Correlation was calculated between gametocytaemia and prevalence/intensity of infection, and between oocyst and sporozoite load. RESULTS: Significant differences were found in prevalence and intensity of infection between species. Anopheles darlingi showed a higher proportion of infected mosquitoes and higher oocyst and sporozoite intensity than An. deaneorum. Survival analysis showed that An. deaneorum survival decreased drastically until 14 days post infection (dpi). Plasmodium vivax infection decreased survival in both species relative to uninfected mosquitoes. No correlation was observed between gametocytaemia and prevalence/intensity of infection, but oocyst and sporozoite load had a moderate to strong correlation. CONCLUSIONS: Colonized An. darlingi make excellent subjects for modelling pathogen transmission. On the other hand, An. deaneorum could serve as a model for immunity studies due the low susceptibility under current colonized conditions. In the application of DMFA, gametocyte density is not a reliable parameter for predicting mosquito infection by P. vivax, but oocyst intensity should be used to schedule sporozoite experiments.


Assuntos
Anopheles , Malária Vivax , Animais , Humanos , Malária Vivax/epidemiologia , Mosquitos Vetores/parasitologia , Oocistos , Plasmodium vivax , Esporozoítos
15.
Rev. cuba. pediatr ; 94(2)jun. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1409139

RESUMO

RESUMEN El síndrome de escroto agudo es una urgencia quirúrgica, que si no se hace una evolución adecuada y existen demoras en el diagnostico puede el paciente tener daños irreversibles en la viabilidad testicular. Se presenta la Guía de Práctica Clínica sobre el síndrome de escroto agudo con el objetivo de hacer una actualización sobre el tema y proporcionar un instrumento asistencial y docente en los servicios de cirugía pediátrica del país. Varias enfermedades pueden ser la causa de aparición del síndrome de escroto agudo, entre ellas, la torsión testicular, la torsión de hidátides testiculares y la orquiepididimitis. El síntoma fundamental es el dolor testicular y requiere generalmente tratamiento quirúrgico. El tratamiento oportuno de estos pacientes evita complicaciones como la necesidad de orquiectomia, la esterilidad y reincorpora más rápidamente al paciente a su actividad social.


ABSTRACT Acute scrotum syndrome is a surgical emergency, which if an adequate evolution is not made and there are delays in the diagnosis, the patient can have irreversible damage in the testicular viability. The Clinical Practice Guidelines on acute scrotum syndrome is presented with the aim of updating the subject and providing a care and teaching instrument in the pediatric surgery services of the country. Several diseases can be the cause of the onset of acute scrotum syndrome, including testicular torsion, testicular hydatid torsion, and orchiepididymitis. The fundamental symptom is testicular pain and usually requires surgical treatment. The timely treatment of these patients avoids complications such as the need for orchiectomy, sterility, and that way the patient is more quickly reincorporated into his social activity.

16.
Br J Pharmacol ; 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35485850

RESUMO

Breast cancer is the most common type of cancer and the leading cause of death among women. Recent evidence suggests that mesenchymal stromal/stem cells and cancer-associated fibroblasts (CAFs) have an essential role in cancer progression, invasion and therapy resistance. Therefore, they are considered as highly promising future therapeutic targets against breast cancer. The intrinsic tumour tropism and immunomodulatory capacities of mesenchymal stromal/stem cells are of special relevance for developing mesenchymal stromal/stem cells-based anti-tumour therapies that suppress primary tumour growth and metastasis. In addition, the utilization of therapies that target the stromal components of the tumour microenvironment in combination with standard drugs is an innovative tool that could improve patients' response to therapies and their survival. In this review, we discuss the currently available information regarding the possible use of mesenchymal stromal/stem cells-derived anti-tumour therapies, as well as the utilization of therapies that target CAFs in breast cancer microenvironment. Finally, these data can serve as a guide map for future research in this field, ultimately aiding the effective transition of these results into the clinic.

17.
Rev. Fundac. Juan Jose Carraro ; 25(45): 26-31, 2022. ilus
Artigo em Espanhol | LILACS | ID: biblio-1437486

RESUMO

La osteoporosis se caracteriza por una masa ósea baja con deterioro de la microarquitectura del tejido que conduce a la fragilidad, lo que aumenta el riesgo de fracturas. Después de la menopausia, la deficiencia de estrógenos aumenta la exposición del tejido al ligan- do RANK, lo que resulta en un aumento de la reabsorción y pérdida ósea, que pueden provocar osteoporosis. (1) Los bifosfonatos y el denosumab son utilizados para el tratamiento de la osteoporosis debido a su capacidad anticatabólica, que reducen la remodelación previniendo la pérdida de masa ósea, disminuyendo la probabilidad de fracturas y aumentando la densidad mineral del tejido. (2) La osteonecrosis de los maxilares asociadas a drogas antirresortivas es una situación que se presenta en pacientes que consumen de manera crónica antirresortivos para el tratamiento de enfermedades como: osteoporosis, osteogénesis imperfecta, enfermedad de Paget, displasia fi- brosa, hipercalcemia maligna asociada a tratamiento oncológico (AU)


Osteoporosis is characterized by low bone mass with deterioration of the tissue microarchitec- ture leading to fragility, which increases the risk of fractures. After menopause, estrogen deficiency increases tissue exposure to the RANK ligand, resulting in increased bone loss and resorption, which can lead to osteoporosis. (1) Bisphosphonates and denosumab are used for the treatment in low concentration, due to their anticatabolic capacity, which reduce remodeling, preventing loss of bone mass and fractures besides, antiresorptives drugs increase the mineral density of the tissue. (2) Osteonecrosis of the jaw associated with antiresorptives drugs occurs in patients whose chro- nically consume these drugs for the treatment of diseases such as: osteoporosis, imperfect osteogenesis, Paget's disease, fibrous dysplasia, malignant hypercalcemia associated with oncological treatment (AU)


Assuntos
Humanos , Feminino , Idoso , Osteoporose/complicações , Conservadores da Densidade Óssea/efeitos adversos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Ligante RANK/fisiologia , Denosumab/efeitos adversos , Reabilitação Bucal/métodos
18.
3 Biotech ; 11(12): 505, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34881167

RESUMO

In 2019, 229 million cases of malaria were recorded worldwide. For epidemiologic surveillance and proper treatment of persons infected with Plasmodium spp., rapid detection of infections by Plasmodium spp. is critical. Thus, Plasmodium spp. diagnosis is one of the indispensable measures for malaria control. Although microscopy is the gold standard for diagnosis, it has restrictions related mainly to the lack of qualified human resources, which is a problem in many regions. Thus, this review presents major innovations in diagnostic methods as alternatives to or complementary to microscopy. Detection platforms in lateral flow systems, electrochemical immunosensors, molecular biology and, more recently, those integrated with smartphones, are highlighted, among others. The advanced improvement of these tests aims to provide techniques that are sensitive and specific, but also quick, easy to handle and free from the laboratory environment. In this way, the tracking of malaria cases can become increasingly effective and contribute to controlling the disease.

19.
Breast Cancer ; 28(6): 1328-1339, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34240315

RESUMO

PURPOSE: Dendritic cells (DCs) are the most potent antigen-presenting cells that play a major role in initiating the antitumor immune response in different types of cancer. However, the prognostic significance of the accumulation of these cells in human early breast tumors is not totally clear. The aim of this study is to evaluate the prognostic relevance of CD1a( +) and CD83( +) dendritic cells in early breast cancer patients. METHODS: We conducted immunohistochemical assays to determine the number of stromal CD1a( +) and CD83( +) DCs in primary tumors from early invasive ductal breast cancer patients, and analyzed their association with clinico-pathological characteristics. RESULTS: Patients with high CD1a( +) DC number had lower risk of bone metastatic occurrence, as well as, longer disease-free survival (DFS), bone metastasis-free survival (BMFS) and overall survival (OS). Moreover, CD1a( +) DC number was an independent prognostic factor for BMFS and OS. In contrast, we found that patients with high number of CD83( +) DCs had lower risk of mix (bone and visceral)-metastatic occurrence. Likewise, these patients presented better prognosis with longer DFS, mix-MFS and OS. Furthermore, CD83( +) DC number was an independent prognostic factor for DFS and OS. CONCLUSION: The quantification of the stromal infiltration of DCs expressing CD1a or CD83 in early invasive breast cancer patients serves to indicate the prognostic risk of developing metastasis in a specific site.


Assuntos
Antígenos CD1/análise , Antígenos CD/análise , Neoplasias da Mama/patologia , Imunoglobulinas/análise , Glicoproteínas de Membrana/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/imunologia , Antígenos CD1/imunologia , Biomarcadores Tumorais/imunologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Feminino , Humanos , Imunoglobulinas/imunologia , Glicoproteínas de Membrana/imunologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
20.
Bioinformatics ; 37(21): 3766-3773, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34086840

RESUMO

MOTIVATION: Protein structure modeling can be improved by the use of distance constraints between amino acid residues, provided such data reflects-at least partially-the native tertiary structure of the target system. In fact, only a small subset of the native contact map is necessary to successfully drive the model conformational search, so one important goal is to obtain the set of constraints with the highest true-positive rate, lowest redundancy and greatest amount of information. In this work, we introduce a constraint evaluation and selection method based on the point-biserial correlation coefficient, which utilizes structural information from an ensemble of models to indirectly measure the power of each constraint in biasing the conformational search toward consensus structures. RESULTS: Residue contact maps obtained by direct coupling analysis are systematically improved by means of discriminant analysis, reaching in some cases accuracies often seen only in modern deep-learning-based approaches. When combined with an iterative modeling workflow, the proposed constraint classification optimizes the selection of the constraint set and maximizes the probability of obtaining successful models. The use of discriminant analysis for the valorization of the information of constraint datasets is a general concept with possible applications to other constraint types and modeling problems. AVAILABILITY AND IMPLEMENTATION: MSA for the targets in this work is available on https://github.com/m3g/2021_Bottino_Biserial. Modeling data supporting the findings of this study was generated at the Center for Computing in Engineering and Sciences, and is available from the corresponding author LM on request. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Aminoácidos , Proteínas , Proteínas/química , Aminoácidos/química
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