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This study aims to investigate the neuroprotective effect of tetramethylpyrazine on mice after spinal cord injury and its mechanism. Seventy-five female C57BL/6 mice were randomly divided into 5 groups, namely, a sham operation group, a model group, a tetramethylpyrazine low-dose group(25 mg·kg~(-1)), a tetramethylpyrazine medium-dose group(50 mg·kg~(-1)), and a tetramethylpyrazine high-dose group(100 mg·kg~(-1)), with 15 mice in each group. Modified Rivlin method was used to establish the mouse model of acute spinal cord injury. After 14 d of tetramethylpyrazine intervention, the motor function of hind limbs of mice was evaluated by basso mouse scale(BMS) and inclined plate test. The levels of inflammatory cytokines tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-1β(IL-1β) in the spinal cord homogenate were determined by enzyme-linked immunosorbent assay(ELISA). Hematoxylin-eosin(HE) staining was used to observe the histology of the spinal cord, and Nissl's staining was used to observe the changes in the number of neurons. Western blot and immunofluorescence method were used to detect the expression of glial fibrillary acidic protein(GFAP) and C3 protein. Tetramethylpyrazine significantly improved the motor function of the hind limbs of mice after spinal cord injury, and the BMS score and inclined plate test score of the tetramethylpyrazine high-dose group were significantly higher than those of the model group(P<0.01). The levels of TNF-α, IL-6, and IL-1β in spinal cord homogenate of the tetramethylpyrazine high-dose group were significantly decreased(P<0.01). After tetramethylpyrazine treatment, the spinal cord morphology recovered, the number of Nissl bodies increased obviously with regular shape, and the loss of neurons decreased. As compared with the model group, the expression of GFAP and C3 protein was significantly decreased(P<0.05,P<0.01) in tetramethylpyrazine high-dose group. In conclusion, tetramethylpyrazine can promote the improvement of motor function and play a neuroprotective role in mice after spinal cord injury, and its mechanism may be related to inhibiting inflammatory response and improving the hyperplasia of glial scar.
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Rats , Souris , Femelle , Animaux , Rat Sprague-Dawley , Neuroprotecteurs/pharmacologie , Facteur de nécrose tumorale alpha/métabolisme , Interleukine-6 , Souris de lignée C57BL , Traumatismes de la moelle épinière/génétique , Moelle spinale/métabolismeRÉSUMÉ
Objective: To explore the clinical application value of two longitudes three transverses method in the location of the perforator of thoracodorsal artery perforator and deep wound repair. Methods: The retrospectively observational study was conducted. From December 2018 to June 2020, 17 patients with deep wounds who were admitted to the Affiliated Hospital of Zunyi Medical University met the inclusion criteria and were included in this study, including 7 males and 10 females, aged 12 to 72 years. The wound areas of patients after debridement were 7 cm×3 cm to 11 cm×7 cm. Two longitudinal lines were located through the midpoint of the armpit, the posterior superior iliac spine, and the protruding point of the sacroiliac joint, and three transverse lines were located 5, 10, and 15 cm below the midpoint of the armpit between the two longitudinal lines, i.e. two longitudes three transverses method, resulting in two trapezoidal areas. And then the thoracodorsal artery perforators in two trapezoidal areas were explored by the portable Doppler blood flow detector. On this account, a single or lobulated free thoracodorsal artery perforator flap or flap that carrying partial latissimus dorsi muscle, with an area of 7 cm×4 cm to 12 cm×8 cm was designed and harvested to repair the wound. The donor sites were all closed by suturing directly. The number and location of thoracodorsal artery perforators, and the distance from the position where the first perforator (the perforator closest to the axillary apex) exits the muscle to the lateral border of the latissimus dorsi in preoperative localization and intraoperative exploration, the diameter of thoracodorsal artery perforator measured during operation, and the flap types were recorded. The survivals of flaps and appearances of donor sites were followed up. Results: The number and location of thoracodorsal artery perforators located before operation in each patient were consistent with the results of intraoperative exploration. A total of 42 perforators were found in two trapezoidal areas, with 2 or 3 perforators each patient. The perforators were all located in two trapezoid areas, and a stable perforator (the first perforator) was located and detected in the first trapezoidal area. There were averagely 1.47 perforators in the second trapezoidal area. The position where the first perforator exits the muscle was 2.1-3.1 cm away from the lateral border of the latissimus dorsi. The diameters of thoracodorsal artery perforators were 0.4-0.6 mm. In this group, 12 cases were repaired with single thoracodorsal artery perforator flap, 3 cases with lobulated thoracodorsal artery perforator flap, and 2 cases with thoracodorsal artery perforator flap carrying partial latissimus dorsi muscle. The patients were followed up for 6 to 16 months. All the 17 flaps survived with good elasticity, blood circulation, and soft texture. Only linear scar was left in the donor area. Conclusions: The two longitudes three transverses method is helpful to locate the perforator of thoracodorsal artery perforator flap. The method is simple and reliable. The thoracodorsal artery perforator flap designed and harvested based on this method has good clinical effects in repairing deep wound, with minimal donor site damage.
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Adolescent , Adulte , Sujet âgé , Enfant , Femelle , Humains , Mâle , Adulte d'âge moyen , Jeune adulte , Artères , Lambeau perforant , 33584/méthodes , Études rétrospectives , Transplantation de peau , Traumatismes des tissus mous/chirurgie , Résultat thérapeutiqueRÉSUMÉ
OBJECTIVE@#To study the role of miR-431 in lung development and morphology.@*METHODS@#According to the stage of lung development in rats, Sprague-Dawley rats at embryonic day 16 (E16), embryonic day (E19), embryonic day (E21), postnatal day 1 (P1), postnatal day 3 (P3), postnatal day 7 (P7), postnatal day 14 (P14) and 10 weeks after birth (P10 weeks) were selected, and lung tissue samples were collected for observation. Hematoxylin-eosin staining and transmission electron microscopy were performed to observe the morphology of lung tissue. Fluorescence in situ hybridization and real-time PCR were used to measure the expression of miR-431 during the critical stages of lung development (E19, E21 and P3).@*RESULTS@#The E19 group had the formation of the lamellar body and type II alveolar epithelial cells in the fetal lung tissue. The number of lamellar bodies increased with the increasing gestational age, with aggregation and excretion. Pulmonary alveoli formed rapidly, the lung interstitium became thinner, and the microvascular system became mature after birth. Fluorescence in situ hybridization and real-time PCR showed that the expression of miR-431 gradually decreased with the increasing gestational age (P<0.05).@*CONCLUSIONS@#The systematic and continuous morphological data of lung development is obtained in this experiment. In addition, miR-431 may play an important role in the negative regulation of lung development, which provides basis and direction for further research on the mechanism of lung development and related diseases.
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Animaux , Rats , Foetus , Hybridation fluorescente in situ , Poumon , microARN , Rat Sprague-DawleyRÉSUMÉ
BACKGROUND: Micro-arc oxidation (MAO) treatment can improve the biological properties of titanium alloy implants. Previous studies mostly focused on the evaluation of titanium alloy plate, while the effects of the MAO-modified 3D titanium scaffold on the cell growth and differentiation were rarely reported. OBJECTIVE: To investigate the effect of MAO coating on the biological performance of cells seeded onto the 3D-printed porous titanium alloy scaffold. METHODS: Rat bone marrow mesenchymal stem cells were seeded onto the MAO-modified Ti6Al4V alloy scaffolds (experimental group) and unmodified scaffolds (control group). After 4 and 7 days of culture, cell/scaffold constructs were retrieved and processed for the assessment of cell morphology by using scanning electron microscopy, cytoskeletal staining analysis and cell viability assay were also evaluated. At 4, 7 and 11 days of culture, the levels of alkaline phosphatase and osteocalcin in the cell supernatant were detected. At 1, 4, 7 and 11 days of culture, the cell proliferation rate was measured using the MTT assay. RESULTS AND CONCLUSION: (1) At 4 and 7 days of culture, live/dead staining showed that the bone marrow mesenchymal stem cells grew well on the two kinds of scaffolds. The analysis of cytoskeleton staining showed that the cytoskeleton of the experimental group was stereo and polygonal, while the cells on the scaffold surface in the control group were flat and spindle-shaped, spreading along the macro structure of the scaffolds. Under the scanning electron microscopy, the cells in the experimental group arranged closely and spread in a good condition, with interconnected lamellipodia and filopodia that firmly adhered to the scaffold surface in an anchor-shaped structure; in the control group, less filopodia interconnected, less extracellular matrix, and flat and sheet-like cells were observed. (2) With the time increase, the levels of alkaline phosphatase and osteocalcin increased gradually in both groups. The alkaline phosphatase level in the experimental group was significantly higher than that in the control group at 7 and 11 days of culture (P < 0.05), while the osteocalcin level was higher in the experimental group than the control group at 11 days of culture (P < 0.05). (3) With the prolongation of culture time, the number of cells in the two groups increased gradually. The number of cells cultured in the experimental group was significantly higher than that in the control group at 7 and 11 days of culture (P < 0.05). To conclude, the MAO-modified titanium alloy scaffold is favorable for cell adhesion, proliferation and differentiation.
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Objective To investigate the effect of continuous nursing intervention on post-hospital rehabilitation of chil-dren with cerebral palsy. Methods A total of 70 children with cerebral palsy treated in the First Affiliated Hospital of Xinx-iang Medical University from February 2016 to February 2017 were selected and divided into observation group and control group according to nursing measures,with 35 cases in each group. The patients in the control group were given routine nursing intervention,and the patients in the observation group were given continuous nursing intervention after discharge. The fine mo-tor was evaluated by Peabody-2 developmental motor scale at discharge and one year after discharge. The clinical effect was e-valuated one year after discharge. Results The score of grasping ability and visual movement comprehensive ability of the children in the observation group was 41. 15 ± 5. 31 and 102. 23 ± 17. 42 respectively at discharge,and it was 48. 12 ± 3. 54 and 128. 22 ± 11. 25 respectively one year after discharge. The score of grasping ability and visual movement comprehensive a-bility of the children in the control group was 41. 22 ± 5. 22 and 102. 56 ± 17. 31 respectively at discharge,and it was 43. 21 ± 4. 52 and 110. 52 ± 15. 37 respectively at one year after discharge. There was no significant difference in the scores of grasping ability and visual motor comprehensive ability between the two groups at discharge(P > 0. 05). The scores of grasping ability and visual motor comprehensive ability at the time point of one year after discharge were significantly higher than those at dis-charge in the two groups(P < 0. 05). The scores of grasping ability and visual motor comprehensive ability in the observation group were significantly higher than those in the control group at the time point of one year after discharge(P < 0. 05). One year after discharge,the total effective rate of rehabilitation treatment in the observation group and the control group was 94. 29%(33 / 35)and 71. 43%(25 / 35)respectively,and the total effective rate in the observation group was significantly high-er than that in the control group(χ2 =6. 440,P <0. 05). Conclusion The continuous nursing intervention can significantly im-prove the grasping ability and visual motor comprehensive ability,and promote the recovery of children with cerebral palsy.
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<p><b>OBJECTIVE</b>To investigate the correlation of CD4CD29regulatory T cells (Treg) with tumor recurrence and survival time in patients with non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>Fifty-nine patients with NSCLC treated with radical surgery were followed up for 5 years. Blood Treg cells were examined during the follow-up using flow cytometry (FCM). The sensitivity and specificity of Treg cells to predict recurrence of NSCLC were analyzed using receiver-operating characteristic (ROC) curve and compared with those of carcinoembryonic antigen (CEA) and cytokeratin21-1 (Cyfra21-1). The influences of gender, age, occupation and radiotherapy on survival time of the patients were analyzed with Kaplan-Meier method.</p><p><b>RESULTS</b>Among the 59 patients, the shortest survival time was 23 months while the longest time was over 67 months. Nineteen patients had NSCLC recurrence, and 17 (28.81%) of them died of metastasis during the follow-up. The frequencies of blood Treg cells in patients who did not receive radiotherapy and in patients with tumor recurrence were significantly higher than those in patients receiving radiotherapy and in patients free of recurrence (P=0.000). ROC curves showed that the area under curve (AUC) lowered in the order of Treg cells, Cyfra21-1, CEA (P=0.002, 0.006 and 0.013, respectively) with 95% confidence interval (CI) of 0.649-0.981, 0.621-0.936 and 0.584-0.944, respectively. At the cut-off value of 7.53%, the sensitivity and specificity of Treg cells to predict NSCLC recurrence was 91.42% and 87.59%, respectively. The five-year survival rate of the 59 patients was 71.18% (42/59), and Kaplan-Meier analysis revealed a longer survival time in female patients (P=0.038), in patients below 50 years of age (P=0.013), in patients not engaging in mental work (P=0.029), and in patients receiving radiotherapy (P=0.003).</p><p><b>CONCLUSION</b>Treg cells has a better efficiency than Cyfra21-1 and CEA to predict tumor recurrence in patients with NSCLC following radical surgery. The male gender, an age beyond 50 years, an occupation of mental work, and failure to receive radiotherapy are all risk factors for recurrence of NSCLC.</p>
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Objective To study the effect of Phenobarbital (PB) on experimental rats,observe the histological changes of immature brain and the expressions of apoptosis-related proteins Bcl-2 and Bax in neurons detected by immunohistochemistry,and to explore the influence and mechanism of PB on brain damage at therapeutic levels to immature brain maturation of rat in order to provide the theoretical and experimental base for clinic.Methods A total of 40 healthy 18-day-old Sprague-Dawley(SD) rats (male or female) were randomly assigned into 2 groups:normal saline (NS) treated as control group(20 cases),PB group(20 cases).Each group was further randomly divided into longterm(4 weeks) treated group and short-term(2 weeks) treated group(10 rats in each group).The rats in PB group received intragastricadministration with PB (30 mg/kg).The rats in control group were handled by injection of NS into stomach and abdomen according to 4 mL/kg.All performances were undertaken for twice every day.At the end of the therapeutic period,body and brain weight were measured when the rats were sacrificed.Histological studies on the tissues of frontal lobes and hippocampus were performed by Hematoxylin-Eosin(HE) staining and Nissl staining.Expressions of apoptosis-related proteins Bcl-2 and Bax in neurons were detected by immunohistochemistry.Results There were no significant differences in body and brain weights or histological studies index among control group as well as PB group before and after treatment for short term(P >0.05).Remarkable reduction of brain weight was only observed in immature rats exposed to PB compared to control group for long period,and significant neurodegeneration,neuronal necrosis were observed in immature rats exposed to PB compared to control group(all P < 0.01).The expression of Bax protein in the frontal lobe increased significantly in immature rats receiving PB for long period comparing with control (P<0.01).In contrast,expression of Bcl-2 protein did not change at therapeutic level.The ratio of Bax/Bcl-2 was obviously increased.Conclusions Chronic treatment with PB will result in significant neuronal apoptosis and necrosis and persistent cognitive impairment and brain damage to immature rates.Brain damage of PB at therapeutic level to immature brain may be irreversible.The significant expression of Bax protein in the frontal lobe and the high rate of Bax/Bcl-2 are probably the main reasons which cause brain weight decreasing and brain damage by PB in immature brain tissue.
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<p><b>OBJECTIVE</b>To observe the efficacy of micro-arc oxidation and alkali-heat treatment (MAH) on Ti-24Nb-4Zr-8Sn (Ti2448).</p><p><b>METHODS</b>Disks (diameter of 14.5 mm, thickness of 1 mm) and cylinders (diameter of 3 mm, height of 10 mm) were fabricated from Ti2448 alloy. Samples were divided into three groups: polished (Ti2448), micro-arc oxidation(MAO-Ti2448), micro-arc oxidation and alkali-heat treatment (MAH-Ti2448). MC3T3-E1 osteoblastic cells were cultured on the disks and cell morphology was observed with scanning electron microscopy (SEM) aftre 3 days. The cylinder samples were implanted in the tibia of dogs and implant-bone interface was observed with SEM after 3 months.</p><p><b>RESULTS</b>A rough and porous structure was shown in both MAO and MAH group. The MC3T3-E1 cells on the MAH-Ti2448 discs spread fully in intimate contact with the underlying coarse surface through active cytoskeletal extentions. Osseointegration was formed in the implant-bone interface in MAH samples.</p><p><b>CONCLUSIONS</b>MAH treatment can provide a more advantageous Ti2448 surface to osteoblastic cells than MAO treatment does, and the former can improve the implant-bone integration.</p>
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Animaux , Chiens , Souris , Alcalis , Alliages , Chimie , Cellules cultivées , Alliage dentaire , Température élevée , Microscopie électronique à balayage , Ostéo-intégration , Ostéoblastes , Biologie cellulaire , Oxydoréduction , Prothèses et implants , Implantation de prothèse , Propriétés de surface , Tibia , Chirurgie généraleRÉSUMÉ
Objective: To investigate the effect of up-regulation of miR-181a expression mediated by constructing miR-181a recombinant eukaryotic expression vector pcDNA3.1(+)-miR-181a on cell proliferation, migration and invasion abilities of esophageal carcinoma cell line TE11. Methods: PCR primers were designed and miR-181a precursor sequence was amplified from 95C cell genomic DNA. The product fragments were cloned into pcDNA3.1(+) to construct the recombinant vector pcDNA3.1(+)-miR-181a. The recombinant eukaryotic expression vector pcDNA3.1(+)-miR-181a was transfected into TE11 cells. The expression of miR-181a mRNA was detected by real-time fluorogenic quantitative-PCR (RFQ-PCR). The effects of pcDNA3.1(+)-miR-181a on cell proliferation, migration and invasion abilities of TE11 cells were detected by MTT, wound healing and Boyden chamber methods, respectively. Results: The miR-181a recombinant eukaryotic expression vector pcDNA3.1(+)-miR-181a was successfully established. RFQ-PCR revealed that the mature miR-181a was able to effectively express in TE11 cells transfected with recombinant vector pcDNA3.1(+)-miR-181a (P<0.05). The overexpression of miR-181a could significantly increase the proliferation, migration and invasion abilities of TE11 cells. Conclusion: Overexpression of miR-181a can increase cell proliferation, migration and invasion abilities of esophageal carcinoma TE11 cells. These results may provide experiment references for further research of the role of miR-181a in cancer development and progression. Copyright© 2011 by Tumor.
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<p><b>AIM</b>To study the relation between Respiratory Syncytial Virus infection and asthma development by measuring airway responsiveness (AR) and M2R function.</p><p><b>METHODS</b>Guinea pigs (n = 34) were randomly divided into 4 groups: Hep-2/NS group (group A, n = 9), RSV/NS group (group B, n =9), Hep-2/OVA group (group C, n = 8) and RSV/OVA group(group D, n = 8). On day 21 after infection we tested AR and M2R. Then counted eosinophils in BALF and observed pathological change.</p><p><b>RESULTS</b>Intraairway pressure(IP mmH20) of group B had no significant difference with group A(P > 0.01), and the extent of IP decrease also had no difference between groups A and B (P > 0. 05), but IP of C group were much higher than group A (P<0.05), with extent of IP decrease lower than group A (P < 0.05). And IP of group D were higher than group C (P < 0.01), with the extent of IP decrease much lower than group C (P < 0.05).</p><p><b>CONCLUSION</b>RSV infection could enhance OVA-induced M2R dysfunction, then develop AHR.</p>
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Animaux , Femelle , Mâle , Asthme , Allergie et immunologie , Virologie , Hyperréactivité bronchique , Allergie et immunologie , Virologie , Cochons d'Inde , Ovalbumine , Allergie et immunologie , Répartition aléatoire , Récepteur muscarinique de type M2 , Physiologie , Infections à virus respiratoire syncytial , Allergie et immunologie , Virus respiratoires syncytiaux , Allergie et immunologieRÉSUMÉ
<p><b>AIM</b>To explore the physiopathological mechanisms of airway injury and the effect on the airway responsiveness of rat by inhaled sulfur dioxide(SO2).</p><p><b>METHODS</b>Sixteen SD male rats were divided randomly into 2 groups (n = 8): the control group and SO2 group. The control group was exposed o pure air. SO2 group was exposed to SO2 of the content 1.0 mg/(m(3) x h) 6h daily for consecutive 3 d. At 4th day, we determined the airway responsiveness, collected the bronchoalveolar lavage fluid (BALF), plasma and lung tissue. Then we counted the total cellular score in BALF, measured the plasma SP content and made the immunohistochemistry staining on the lung tissue (HE and SP methods).</p><p><b>RESULTS</b>Compared with the control group, the total cellular score in BALF and plasma SP content in SO2 group's increased significantly ( P < 0.01). HE staining showed there were a great deal of inflammatory cells infiltration under the tunica mucosa bronchiorum; and SP immunohistochemistry staining indicated there were significant changes in numbers of SP-IR positive fibers of SO2group.</p><p><b>CONCLUSION</b>Exposure to low concentration of SO2 would injure healthy rat's airway, and induce airway hyperresponsiveness, neurogenic inflammation is one of its critical pathophysiological mechanisms.</p>
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Animaux , Mâle , Rats , Polluants atmosphériques , Asthme , Bronches , Hyperréactivité bronchique , Bronchite , Liquide de lavage bronchoalvéolaire , Biologie cellulaire , Neurofibres , Physiologie , Inflammation neurogénique , Répartition aléatoire , Rat Sprague-Dawley , Substance P , Sang , Dioxyde de soufreRÉSUMÉ
<p><b>OBJECTIVE</b>To investigate the apoptosis-promoting effect of PDCD5 on human prostate cancer cells PC-3M-1E8.</p><p><b>METHODS</b>PCI-neo and PCI-neo-PDCD5 were transfected into PC-3M-1E8 cells by Lipofectamine 2000, the viability of the cells was analyzed by MTT assay 16 hours after removal of the serum, and the apoptosis was determined by in situ end-labeling and electron microscopy.</p><p><b>RESULTS</b>The viability and growing speed of the transfected cells were significantly decreased and their apoptotic indexes significantly increased as compared with the control group (P < 0.001).</p><p><b>CONCLUSION</b>PDCD5 may significantly inhibit the in vitro growth and promote the apoptosis of human prostate cancer cells PC-3M-1E8.</p>
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Humains , Mâle , Apoptose , Génétique , Physiologie , Protéines régulatrices de l'apoptose , Génétique , Physiologie , Lignée cellulaire tumorale , Méthode TUNEL , Lipides , Chimie , Protéines tumorales , Génétique , Physiologie , Plasmides , Chimie , Génétique , Tumeurs de la prostate , Génétique , Anatomopathologie , RT-PCR , Transfection , MéthodesRÉSUMÉ
Objective To investigate the expression of vascular endothelial growth factor/vcascular endothelial growth factor receptor(VEGF/VEGFR) in bone marrow of children with acute leukemia(AL),and explore their relationship of the clinical features,and observe changes before and after chemotheropy.Methods The bone marrows of 53 children with AL were assayed to study the expression of VEGF/VEGFR(KDR,Flt-1)before and after chemtheropy with S-P immhistochemical staining.Their relations to the clinical features were evaluated.Results The expressions of VEGF,Flt-1,KDR were significantly higher in newly diagnosed children with AL than those of control group.They were significantly higher in children with acute myeloid leukemia(AML) than in children with ALL.The expressions of VEGF,Flt-1,KDR in remission chidren after chemotheropy were significantly lower than before chemotheropy.There was a positive correlation of the percentage of bone marrow blasts with VEGF expression in children with AL.There was also a positive correlation of the percentage of leukemic cell in blood rountine with VEGF expression.For the untreated group of children,no correlation was found between expressions of VEGF,Flt-1,KDR and age,sex,extramedullary infiltration.Conclusions Expression levels of VEGF,Flt-1,KDR in bone marrow of children with AL increases.VEGF/VEGFR may play an important role in process of chidhood AL.
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Objective To understand the current status of hypertension in Jingzhuang Town,Yanqing District,Beijing. Method With randomized cluster sampling,3 653 residents aged over 30 yrs old were investigated by a standard questionnaire on hypertension epidemiology.Result The prevalence rate of hypertension in Jingzhuang Town was 33.3%,and increased with the age(P0.05).The main patients were those with degree 1 hypertension(62.8%).There were 37.8%of people with normal blood pressure who had high-normal values,the highest(44.3%)in 60~69 yr group.In population with hypertension,the rate of people taking medication was 24.5%,disease control rate was 8.6%,while in patients aged 30~49 yrs,these rates were 7.1%and 2.9% respectively.Conclusion The prevalence of hypertension in Beijing's suburb was serious with a younger trend.There was a large part of people with high-normal blood oressure.