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BACKGROUND: There is a great deal of controversy on whether routine MRI examination is needed for fresh fractures while the vast majority of patients with tibial plateau fractures (TPFs) receive preoperative X-ray and CT examinations. The purpose of the study was to analyze the exact correlation between CT images of lateral plateau and lateral meniscus injuries in Schatzker II TPFs. METHODS: A total of 296 patients with Schatzker II TPFs from August 2012 to January 2021 in two trauma centers were enrolled for the analysis. According to the actual situation during open reduction internal fixation (ORIF) and knee arthroscopic surgery, patients were divided into meniscus injury (including rupture, incarceration, etc.) and non-meniscus injury groups. The values of both lateral plateau depression (LPD) and lateral plateau widening (LPW) of lateral tibial plateau on CT images were measured, and their correlation with lateral meniscus injury was then analyzed. The relevant receiver operating characteristic (ROC) curve was drawn to evaluate the optimal cut-off point of the two indicators which could predict meniscus injury. RESULTS: The intra- and inter-observer reliabilities of LPD and LPW were acceptable (intraclass correlation coefficient (ICC) > 0.8). The average LPD was 13.2 ± 3.2 mm while the average value of the group without meniscus injury was 9.4 ± 3.2 mm. The difference between the two groups was statistically significant (P < 0.05). The average LPW was 8.0 ± 1.4 mm and 6.8 ± 1.6 mm in meniscus injury and non-meniscus injury groups with a significant difference (P < 0.05). The optimal predictive cut-off value of LPD and LPW was 7.9 mm (sensitivity-95.0%, specificity-58.8%, area under the curve (AUC-0.818) and 7.5 mm (sensitivity-70.0%, specificity - 70.6%, AUC - 0.724), respectively. The meniscus injury group mainly showed injuries involving the mid-body and posterior horn of lateral meniscus (98.1%, 157/160). CONCLUSIONS: The mid-body and posterior horn of lateral meniscus injury is more likely to occur in patients with Schatzker II TPFs when LPD > 7.9 mm and/or LPW > 7.5 mm on CT. These findings will definitely provide guidance for orthopedic surgeons in treating such injuries. During the operation, more attention is required be paid to the treatment of the meniscus and the possible fracture reduction difficulties and poor alignment caused by meniscus rupture and incarceration should be fully considered in order to achieve better surgical results.
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Fracturas de la Tibia , Lesiones de Menisco Tibial , Fijación Interna de Fracturas , Humanos , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/cirugía , Estudios Retrospectivos , Fracturas de la Tibia/diagnóstico por imagen , Fracturas de la Tibia/cirugía , Lesiones de Menisco Tibial/diagnóstico por imagen , Lesiones de Menisco Tibial/cirugía , Tomografía Computarizada por Rayos XRESUMEN
The exact mechanism of tumour necrosis factor α (TNF-α) promoting osteoclast differentiation is not completely clear. A variety of P2 purine receptor subtypes have been confirmed to be widely involved in bone metabolism. Thus, the purpose of this study was to explore whether P2 receptor is involved in the differentiation of osteoclasts. Mouse bone marrow haematopoietic stem cells (BMHSCs) were co-cultured with TNF-α to explore the effect of TNF-α on osteoclast differentiation and bone resorption capacity in vitro, and changes in the P2 receptor were detected at the same time. The P2 receptor was silenced and overexpressed to explore the effect on differentiation of BMHSCs into osteoclasts. In an in vivo experiment, the animal model of PMOP was established in ovariectomized mice, and anti-TNF-α intervention was used to detect the ability of BMHCs to differentiate into osteoclasts as well as the expression of the P2 receptor. It was confirmed in vitro that TNF-α at a concentration of 20 ng/mL up-regulated the P2X7 receptor of BMHSCs through the PI3k/Akt signalling pathway, promoted BMHSCs to differentiate into a large number of osteoclasts and enhanced bone resorption. In vivo experiments showed that more P2X7 receptor positive osteoclasts were produced in postmenopausal osteoporotic mice. Anti-TNF-α could significantly delay the progression of PMOP by inhibiting the production of osteoclasts. Overall, our results revealed a novel function of the P2X7 receptor and suggested that suppressing the P2X7 receptor may be an effective strategy to delay bone formation in oestrogen deficiency-induced osteoporosis.
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Diferenciación Celular , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Osteoporosis Posmenopáusica/etiología , Osteoporosis Posmenopáusica/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Biomarcadores , Retroversión Ósea/metabolismo , Diferenciación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Femenino , Humanos , Ratones , Osteoclastos/citología , Osteoclastos/metabolismo , Osteoporosis Posmenopáusica/diagnóstico , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ligando RANK/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/farmacología , Microtomografía por Rayos XRESUMEN
Obesity and obesity-related metabolic disorders are global epidemics that occur when there is chronic energy intake exceeding energy expenditure. Growing evidence suggests that healthy dietary patterns not only decrease the risk of obesity but also influence the composition and function of the gut microbiota. Numerous studies manifest that the development of obesity is associated with gut microbiota. One promising supplementation strategy is modulating gut microbiota composition by dietary patterns to combat obesity. In this review, we discuss the changes of gut microbiota in obesity and obesity-related metabolic disorders, with a particular emphasis on the impact of dietary components on gut microbiota and how common food patterns can intervene in gut microbiota to prevent obesity. While there is promise in intervening with the gut microbiota to combat obesity through the regulation of dietary patterns, numerous key questions remain unanswered. In this review, we critically review the associations between dietary patterns, gut microbes, and obesity, aiming to contribute to the further development and application of dietary patterns against obesity in humans.
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The origin of energetic charged particles in universe remains an unresolved issue. Astronomical observations combined with simulations have provided insights into particle acceleration mechanisms, including magnetic reconnection acceleration, shock acceleration, and stochastic acceleration. Recent experiments have also confirmed that electrons can be accelerated through processes such as magnetic reconnection and collisionless shock formation. However, laboratory identifying stochastic acceleration as a feasible mechanism is still a challenge, particularly in the creation of collision-free turbulent plasmas. Here, we present experimental results demonstrating kinetic turbulence with a typical spectrum k-2.9 originating from Weibel instability. Energetic electrons exhibiting a power-law distribution are clearly observed. Simulations further reveal that thermal electrons undergo stochastic acceleration through collisions with multiple magnetic islands-like structures within the turbulent region. This study sheds light on a critical transition period during supernova explosion, where kinetic turbulences originating from Weibel instability emerge prior to collisionless shock formation. Our results suggest that electrons undergo stochastic acceleration during this transition phase.
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The origin of the cosmic magnetic field remains an unsolved mystery, relying not only on specific dynamo processes but also on the seed field to be amplified. Recently, the diffuse radio emission and Faraday rotation observations reveal that there has been a microgauss-level magnetic field in intracluster medium in the early universe, which places strong constraints on the strength of the initial field and implies the underlying kinetic effects; the commonly believed Biermann battery can only provide extremely weak seed of 10-21 G. Here, we present evidence for the spontaneous Weibel-type magnetogenesis in laser-produced weakly collisional plasma with the three-dimensional synchronous proton radiography, where the distribution anisotropy directly arises from the temperature gradient, even without the commonly considered interpenetrating plasmas or shear flows. This field can achieve sufficient strength and is sensitive to Coulomb collision. Our results demonstrate the importance of kinetics in magnetogenesis in weakly collisional astrophysical scenarios.
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Germ cell tumours with somatic-type solid malignancy (GCT-STM) are a rare disease of the mediastinum. Recently, a cohort of vasculogenic mesenchymal tumour (VMT)-nonseminoma cases with different prognoses were recognized and reported. Here, we report a case of mediastinal high-grade VMT with a seminoma. A 16-year-old male had a fever, chest tightness and fatigue. Chest CT showed a 7.5 cm×5.3 cm solid mass in the right anterior mediastinum. The serum levels of alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (ß-HCG) and carcinoembryonic antigen (CEA) were within the normal range. Tumorectomy was performed. The tumour was irregular, and no capsule was found. The cut surface was greyish white and greyish brown with medium consistency. There were foci of bleeding and necrosis. Microscopic histology showed prominent vascular proliferation, which was lined by mildly atypical endothelial cells in a cellular stroma with significant cytologic atypia. The vascular spectrum varied from crevice-like or antler-like thin- to thick-walled vessels. Beyond the tumour area, inside the remnant thymus tissues, there were small clusters of polygonal tumour cells with clear cytoplasm, distinct cell membranes, and round to polygonal nuclei with prominent nucleoli that were positive for Oct4, PLAP, SALL4 and CD117. The patient did not receive any treatments pre- or postoperation, and his condition was stable without progression after 14 months of follow-up evaluation. Here, we added a new entity of GCT-STM of the mediastinum composed of VMT and seminoma. A better understanding of the pathological features of GCT-VMT could help pathologists improve their awareness of these rare diseases.
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Neoplasias del Mediastino , Neoplasias de Células Germinales y Embrionarias , Seminoma , Neoplasias Testiculares , Masculino , Humanos , Adolescente , Seminoma/patología , Mediastino/patología , Células Endoteliales/patología , Neoplasias Testiculares/cirugía , Neoplasias Testiculares/patología , Neoplasias del Mediastino/patologíaRESUMEN
Intervertebral disc degeneration (IVDD), a common cartilage-degenerative disease, is considered the main cause of low back pain (LBP). Owing to the complex aetiology and pathophysiology of IVDD, its molecular mechanisms and definitive treatment of IVDD remain unclear. As an evolutionarily and functionally conserved signalling pathway, Hippo-YAP/TAZ signalling plays a crucial role in IVDD progression. In this review, we discuss the regulation of Hippo-YAP/TAZ signalling and summarise the recent research progress on its role in cartilage homeostasis and IVDD. We also discuss the current application and future prospects of IVDD treatments based on Hippo-YAP/TAZ signalling.
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Degeneración del Disco Intervertebral , Disco Intervertebral , Humanos , Vía de Señalización Hippo , Transducción de Señal , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZRESUMEN
Introduction: Plaque rupture in atherosclerosis contributes to various acute cardiovascular events. As a new sulfide-containing donor, S-propargyl-cysteine (SPRC) has been reported to play a beneficial role in cardioprotection, potentially through its anti-inflammatory, anti-oxidative and anti-atherogenic activities. Our previous study observed an increase in eNOS phosphorylation in endothelial cells. However, it remains unclear whether SPRC influences vascular smooth muscle cells (VSMCs) within the plaque and if this effect contributes to plaque stabilization. Methods: An atherosclerotic unstable plaque mouse model was established by subjecting ApoE-/- mice to tandem stenosis of the right carotid artery along with a Western diet. Daily SPRC administration was conducted for 13 weeks. Plaque morphology and stability were assessed using MRI scanning and histopathological staining. In our in vitro studies, we stimulated human artery vascular smooth muscle cells (HAVSMCs) with platelet-derived growth factor-BB (PDGF-BB), both with and without 100 µM SPRC treatment. Cell phenotype was assessed using both Western blot and Real-time PCR. Cell proliferation was assessed using the BrdU cell proliferation kit and immunofluorescence of Ki-67, while cell migration was measured using scratch wound healing and transwell assay. MiR-143-3p overexpression and knockdown experiments were used to investigate whether it mediates the effect of SPRC on VSMC phenotype. Results and Discussion: SPRC treatment reduced plasma lipid levels, increased collagen content and decreased cell apoptosis in atherosclerotic plaques, indicating improved plaque stability. Both in vivo and in vitro studies elucidated the role of SPRC in preserving the contractile phenotype of VSMCs through up-regulation of miR-143-3p expression. Furthermore, SPRC suppressed the pro-proliferation and pro-migration effects of PDGF-BB on HAVSMCs. Overall, these findings suggest that the inhibitory effect of SPRC on phenotype switch from contractile to synthetic VSMCs may contribute to its beneficial role in enhancing plaque stability.
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Allergic rhinitis (AR) is a type I hypersensitivity reaction disease caused by inhaled allergens and immunoglobulin E (IgE)-mediated. Noncoding RNA (ncRNA) is an important regulator involved in gene expression and can be detected in the cytoplasm or extracellular fluid, which mainly includes microRNAs (miRNA, length 22-24 nucleotides), long noncoding RNAs (lncRNA, length >200 nucleotides), and circRNAs. LncRNA and miRNA both participate in the regulation of immune function. Some respiratory viral infections can aggravate allergic rhinitis, such as a respiratory syncytial virus (RSV) and human metapneumovirus (hMPV). However, the interaction between viral infection and allergy is complex and the mechanism is still unclear. In this review, we summarized the interactions of noncoding RNAs and viruses in the occurrence and development of AR, along with the treatments focusing on the noncoding RNAs in the past five years.
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BACKGROUND: It is crucial to diversify the methods for clinical nurses to continue learning nursing ethics in that ethical decision-making ability in nursing is regarded as one of the core competencies in nursing practice. OBJECTIVE: In response to nurses' learning needs for nursing ethics, this study built an online learning platform for the pertinent topic, and tested its effect on improving nurses' ethical decision-making ability and critical thinking ability. DESIGN: A qualitative method was adopted to develop interventions, which were designed as a teaching practice research consisting of a study group and a control group. PARTICIPANTS: A total of 93 nurses, including 20 interviewees and 30 in the study group and 43 in the control group. METHOD: Qualitative methods were employed to understand the learning needs of nurses. The judgment about nursing decisions and the critical thinking disposition inventory, learning effectiveness questionnaire and learning software quality evaluation scale were used as research tools in this teaching practice research. The SPSS 25.0 was adopted to analyze data by paired sample t-test and independent sample t-test. RESULTS: In the measurement of the judgment about nursing decisions scale, the study group scored higher than the control group. The critical thinking disposition inventory scale identified a similar result in the total score incorporating the four dimensions, including analyticity, systematicity, critical thinking self-confidence, inquisitiveness. There is a correlation between learning software quality and learning effect, with a correlation coefficient of 0.640. CONCLUSION: The online learning platform of nursing ethics built in this study has positive learning effects, and it demonstrates effectiveness to improve nurses' abilities in nursing ethics, decision-making and critical thinking. It is expected to be a viable way to improve the continuity of nurses' study of ethics.
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Educación a Distancia , Ética en Enfermería , Estudiantes de Enfermería , Humanos , Aprendizaje , PensamientoRESUMEN
The relationship between the bone mass loss and bone marrow haematopoiesis in osteoporosis remains obscure. We selected 3-month-old female Sprague-Dawley rats and randomly divided them into six groups. Three groups were ovariectomized (OVX), while the other three groups were sham operated (Sham). Four, 8 and 12 weeks after the surgical procedure, the rats were euthanized and sampled. The left femur was used for measurement of bone mineral density (BMD). The right femur distal metaphysic cancellous bone was processed for morphological evaluation. Our results showed that the femur BMD in the 4-week OVX group was not significantly decreased compared with that of the 4-week Sham group, but that the volume of adipose tissue in the bone marrow was markedly increased. The femur BMD in the 8-week OVX group was decreased significantly compared with that of the 8-week Sham group (P < 0.05). Meanwhile, the volume of haematopoietic tissue decreased and the volume of adipose tissue increased. The number of megakaryocytes was decreased (P < 0.05). Interestingly, the osteoclasts and mast cells were increased in number in the 8-week OVX group (P < 0.05). These changes became obvious in the 12-week OVX rats, in contrast to the Sham groups. The volume of trabecular bone and the number of osteoblasts in the 12-week OVX group decreased significantly. Increased reticulin fibres were observed only in the 12-week OVX group. Our studies demonstrated a reciprocal correlation between bone-forming osteoblasts and marrow adipose tissue and suggest that OVX rats may be valuable as an animal model to study hypohaemopoiesis.
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Densidad Ósea/fisiología , Hematopoyesis/fisiología , Osteoporosis/fisiopatología , Adipocitos/patología , Tejido Adiposo/patología , Animales , Células de la Médula Ósea/patología , Modelos Animales de Enfermedad , Femenino , Fémur/fisiopatología , Mastocitos/patología , Osteoblastos/patología , Osteoclastos/patología , Osteoporosis/patología , Ovariectomía , Ratas , Ratas Sprague-DawleyRESUMEN
OBJECTIVES: To better realize the features of peripheral blood (PB), bone marrow (BM) aspirate and especially BM trephine biopsy in atypical chronic myeloid leukemia (aCML). METHODS: We studied PB, BM smears in 35 cases of aCML and compared with 84 cases of chronic granulocytic leukemia chronic phase (CGL-CP), 39 cases of chronic myelomonocytic leukemia (CMML). In addition, we evaluated characteristics of BM trephine biopsies in 21 cases of aCML and compared with 68 cases of CGL-CP, 20 cases of CMML. RESULTS: All aCML patients presented with leukocytosis (median WBC 17.3 x 10(9)/L), 48% had moderate anemia, and 85% had thrombocytopenia. Values of monocytes, eosinophils, basophils, percentage of immature granulocytes and monocytes (0.63 +/- 0.41 x 10(9)/L, 0.18 +/- 0.16 x 10(9)/L, 0.09 +/-0.08 x 10(9)/L, 6.27 +/- 3.09%, and 2.46 +/- 1.75%, respectively) were useful in distinguishing aCML from CGL-CP and CMML groups. The BM smears showed that striking dysgranulopoieis (100%), dyserythropoiesis (48.6%), percentage of blasts, nucleated erythrocytes, monocytes, eosinophils, and basophils (2.45 +/- 2.06%, 7.76 +/- 2.89%, 1.30 +/- 1.21%, 1.47 +/- 1.60%, and 1.15 +/- 1.08%, respectively) were all important parameters for a diagnosis of aCML. On BM trephine sections, aCML was characterized as hypercellularity, a moderate degree of reticulin fibrosis (71.4%), lymphocytopenia (76.2%), plasmacytopenia (90.5%), abnormal localization of immature precursors (28.5%), and absence of eosinophilia, basophilia, monocytosis. Furthermore, BM imprints, immunohistochemical, and cytochemical staining findings provided important morphological reference to BM trephine sections and made the identification of nucleated cells more convenient. CONCLUSIONS: Besides the findings observed in PB and BM aspirate, features of BM trephine biopsy (including BM trephine section, BM imprint, immunohistochemical, and cytochemical staining) can also aid in the diagnosis of aCML.
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Células Sanguíneas/patología , Médula Ósea/patología , Leucemia Mieloide Crónica Atípica BCR-ABL Negativa/diagnóstico , Anciano , Anciano de 80 o más Años , Biopsia , Examen de la Médula Ósea , Diagnóstico Diferencial , Femenino , Histocitoquímica , Humanos , Inmunohistoquímica , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Leucemia Mielomonocítica Crónica/diagnóstico , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: Chemokine receptor CXCR2 has been implied to play a substantial role in pathogenesis of atherosclerosis, but the underlying molecular mechanisms remain to be clarified. In the present study, we examined the modulating effect of oxLDL on expression of CXCR2 and its functional effect in monocytes. METHODS AND RESULTS: OxLDL (20-microg protein/ml), but not LDL (80-microg protein/ml), upregulated the surface expression of the CXC chemokine receptor CXCR2 (measured by flow cytometry) in both human freshly peripheral blood monocytes and human monocytic U937 cells. OxLDL, but not LDL, increased CXCR2 mRNA determined by RT-PCR in both cells. Treatment of oxLDL (40-microg protein/ml) enhanced chemotaxis of U937 cells to IL-8 and their adhesion to an endothelial cell line, ECV304 (both P<0.05 vs. control). Pretreatment of monocytes with scavenger receptor inhibitors, polyinosinic acid (100 microg/ml) and dextran sulfate (50 microg/ml) attenuated CXCR2 expression, but pertussis toxin or cholera toxin had no effect. OxLDL induced the activation of p38MAPK in monocytes, and this effect of oxLDL was blocked by the scanvenger receptor inhibitors. Furthermore, p38 MAPK inhibitors SB203580 or SK&F86002 markedly reduced oxLDL-induced CXCR2 expression. CONCLUSIONS: This observation demonstrated that oxLDL upregulates CXCR2 expression in monocytes and promotes the chemotaxis and adhesion of monocytes. The effect of oxLDL is mediated through scavenger receptor and p38 MAPK activation.
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Lipoproteínas LDL/farmacología , Proteínas de la Membrana , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Monocitos/metabolismo , Receptores de Interleucina-8B/metabolismo , Receptores de Lipoproteína , Adhesión Celular , Quimiotaxis de Leucocito , Técnicas de Cocultivo , Sulfato de Dextran/farmacología , Endotelio Vascular/citología , Activación Enzimática , Citometría de Flujo , Humanos , Imidazoles/farmacología , Interleucina-8 , Poli I/farmacología , Piridinas/farmacología , ARN Mensajero/análisis , Receptores Inmunológicos/efectos de los fármacos , Receptores de Interleucina-8B/genética , Receptores Depuradores , Receptores Depuradores de Clase B , Tiazoles/farmacología , Células U937 , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
Due to basic processes of psychological essentialism and contagion, one particular token of monetary currency is not always interchangeable with another piece of currency of equal economic value. When money loses its physical form it is perceived as "not quite the same" money (i.e., to have partly lost the original essence that distinguished it from other monetary tokens), diminishing its intuitive link with its original owner. Participants were less likely to recommend stolen or lost money be returned when it had been subsequently deposited in an electronic bank account, as opposed to retaining its original physical form (Studies 1a and 1b). Conversely, an intuitive sense of ownership is enhanced through physical contact with a piece of hard currency. Participants felt the piece of currency a person had originally lost should be returned to him rather than another piece of currency of equivalent value, even when they did not believe he would be able to tell the difference and considered distinguishing it from other money illogical. This effect was reduced when the currency had been sterilized, wiping it clean of all physical traces of its previous owner (Studies 2a, 2b, and 3).
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Economía , Propiedad , Adulto , Envejecimiento/psicología , Emociones , Femenino , Culpa , Humanos , Relaciones Interpersonales , Intuición , Masculino , Persona de Mediana Edad , Política , Desempeño Psicomotor/fisiología , Caracteres Sexuales , Adulto JovenRESUMEN
The developmental characteristics of root border cells (RBCs) and their role in protection of root apices of rice seedling from Al toxicity were evaluated in two rice (Oryza sativa L.) cultivars differing in Al tolerance. Root elongation and RBCs viability were used as indicators for Al effects. The formation of RBCs and the emergence of the root tip occurred almost simultaneously. Treatment of the root with Al inhibited root elongation and increased Al accumulation in the root tips. Physical removal of RBCs from root tips resulted in a more severe inhibition of root elongation and a higher Al accumulation in the root tips. These effects were more pronounced in the Al-sensitive rice cultivar (II You 6216) than that in the Al-tolerant rice cultivar (II You 838). The relative viability of attached and detached RBCs decreased with increasing Al concentrations. Al also induced a thicker mucilage layer surrounding attached RBCs of both cultivars, and detached RBCs did not. Maintaining the abundant live RBCs encapsulated root tip and enhancing their mucilage secretion, appear to be important in alleviating Al toxicity and in allowing exclusion of Al from the rice root apex.
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Aluminio/toxicidad , Oryza/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Variación Genética , Oryza/citología , Oryza/crecimiento & desarrollo , Raíces de Plantas/citología , Raíces de Plantas/crecimiento & desarrollo , Plantones/efectos de los fármacos , Especificidad de la EspecieRESUMEN
AIM: To study the effect of 17beta-estradiol on expression of chemokine receptor CXCR2 in monocytes in vivo. METHODS: Expressions of chemokine receptor CXCR2 mRNA and protein were measured by RT-PCR and flow cytometry, respectively. RESULTS: In both ovary-intact and ovariectomized (OVX) rats, CXCR2 protein and mRNA expression were significantly increased in rats fed with a high-cholesterol diet for 6 weeks. The cholesterol-induced increases in CXCR2 protein and mRNA expression were significantly attenuated in OVX rats injected with estradiol-17beta (17beta-E2) (5 and 20 microg x kg(-1) x d(-1)). In normal diet rats, CXCR2 protein and mRNA expression were increased in OVX rats compared with ovary-intact rats, and this increase was prevented by 17beta-E2. CONCLUSION: Both basal and hypercholesterolemia-induced increases in chemokine receptor CXCR2 are modulated by physiological concentrations of estradiol.