Objective To elucidate the mechanisms of interface disruption between the actin filament and membrane of the cell pseudopodium that occurs during the breakage of the pseudopodium.Methods Time-lapse images of the behavior of actin filaments and membranes during the rupture process of cell pseudopodia were captured using the confocal microscopy.A theoretical model of the fracture of a cylindrical interface was developed to analyze the interface damage between the actin filament and the membrane during the breakage of the cell pseudopodium.Molecular dynamics simulations were employed to simulate the breaking process of the cell pseudopodium for comparison with the theoretical results.A finite element model considering the coupling of the tensile and torsional deformation of actin filaments was developed to simulate the torsional deformation of actin filaments under tension,both in the presence and absence of a membrane.Results The theoretical results indicated an exponential relationship between the critical load for the broken interface and crack length.The critical load increased with the interfacial strength.The effect of the fiber diameter on the critical load depended on the crack length,exhibiting different effects for small and large crack lengths.Finite element analysis suggested that the membrane substantially constrained torsional movement when the actin filament was extended.Conclusions This study revealed the breaking process of cell pseudopodia and the mechanical aspects underlying the disruption of the interface between the actin filament and the membrane.These results provide theoretical support for exploring cellular behaviors associated with pseudopodium breakage,such as the release of extracellular vesicles.

Humans ; COVID-19 ; Consensus ; SARS-CoV-2 ; China

Critical ultrasonography(CUS) is different from the traditional diagnostic ultrasound,the examiner and interpreter of the image are critical care medicine physicians.The core content of CUS is to evaluate the pathophysiological changes of organs and systems and etiology changes.With the idea of critical care medicine as the soul,it can integrate the above information and clinical information,bedside real-time diagnosis and titration treatment,and evaluate the therapeutic effect so as to improve the outcome.CUS is a traditional technique which is applied as a new application method.The consensus of experts on critical ultrasonography in China released in 2016 put forward consensus suggestions on the concept,implementation and application of CUS.It should be further emphasized that the accurate and objective assessment and implementation of CUS requires the standardization of ultrasound image acquisition and the need to establish a CUS procedure.At the same time,the standardized training for CUS accepted by critical care medicine physicians requires the application of technical specifications,and the establishment of technical specifications is the basis for the quality control and continuous improvement of CUS.Chinese Critical Ultrasound Study Group and Critical Hemodynamic Therapy Collabration Group,based on the rich experience of clinical practice in critical care and research,combined with the essence of CUS,to learn the traditional ultrasonic essence,established the clinical application technical specifications of CUS,including in five parts:basic view and relevant indicators to obtain in CUS;basic norms for viscera organ assessment and special assessment;standardized processes and systematic inspection programs;examples of CUS applications;CUS training and the application of qualification certification.The establishment of applied technology standard is helpful for standardized training and clinical correct implementation.It is helpful for clinical evaluation and correct guidance treatment,and is also helpful for quality control and continuous improvement of CUS application.

Adult ; Female ; Humans ; Keratin-1 ; genetics ; Keratin-9 ; genetics ; Keratoderma, Palmoplantar ; genetics ; Male ; Middle Aged ; Pedigree

Objective To study the effect of Chinese medicinal compound recipe ( modified Fuzheng Yiliu Decoction, MFYD) on the proliferation of colon cancer HT-29 cells and on the expression of cellular apoptosis gene, Bcl-2, and tumor-inhibiting gene, P53. Methods Colon cancer HT-29 cells were divided into serum containing MFYD groups ( treated with different concentrations of serum containing MFYD) and blank serum group. Methyl thiazolyl tetrazolium ( MTT) , real time cellular analysis ( RTCA) and reverse transcription poly merase chain reaction ( RT-PCR) were used to detect the cell proliferation and mRNA expression of Bcl-2 and P53 separately. Results The proliferation of colon cancer HT-29 cell line was inhibited by MFYD ( P<0.05) in concentration-and time-dependent manner. The Bcl-2 mRNA expression was decreased and p53 mRNA was increased markedly in HT-29 cells after co-culturing with 12% or 15% volume fraction of serum containing MFYD for 48 hours, the differences being significant compared with the blank serum group ( P<0.05). Conclusion MFYD has obvious inhibitory effect on the proliferation of colon cancer HT-29 cells, and its mechanism may be related to down-regulating the expression of Bcl-2 gene and up-regulating the expression of P53 gene.

Objective To improve our understanding of localized Castleman's disease ( Localized Castleman's disease, LCD) ,and to improve its diagnosis and treatment. Methods Clinical characteristics and treatment of 26 LCD cases were retrospectively analyzed, and its clinical features and treatment strategies were reviewed. Results Among the 26 cases, there were 10 cases with clinical symptoms, which mainly showed local pain induced by the compression of the tumors, and 3 in the 10 cases associated with paraneoplastic pemphigus. The swollen lymph node was at a localized area, which was mostly at retroperitoneal (10 cases) and mediastinum (7 cases). The CT scan of LCD had its special characters including local calcification and necrosis. 22 cases were of hyaline vascular type, and the other 4 cases were of plasma type based on histopathologic examination. Twenty-five patients received complete tumor resection and 2 cases of them recurred after a follow-up of 5 to 206 months averaging at 48 ± 13 months. In one case the tumor adjoining vital organs deep in the mediastinum couldn't be completely resected. This patient and another with complete tumor resection recurred and received combined chemotherapy with complete tumor disappearance and were all alive without recurrence as found by follow up to May, 2010. The other patient with recurrent tumor after tumor resection didn't receive chemotherapy and died 11 years later. Conclusions LCD patients mainly have isolated lymphadenectasis, and some patients may have systemic symptom and show abnormal laboratory results. CT scan is helpful in establishing a diagnosis of LCD.Complete surgical resection offers a favorite result for this disease.

Clinical features and related information on diagnosis and treatment of 45 cases of Castleman's disease (CD) were retrospectively analyzed.Based on the clinical classification, localized CD (LCD) was found in 26 cases, multicentric CD (MCD) was found in 19 cases.Most cases of LCD presented the symptoms of compression, while MCD had complicated and non-specific clinical manifestations, making the early diagnosis more difficult.All 26 cases with LCD underwent surgery, among which only 2 cases relapsed.Sixteen out of 19 patients with MCD were treated with glucocorticoids or combined chemotherapy, and 14 cases achieved complete or partial remission.The results show that patients with CD have variant manifestation and the diagnosis depend on CT scan or histopathology examination.Most LCD can be cured by complete surgical resection, and MCD can achieve remission by the treatment with glucocorticoids or combined chemotherapy.

BACKGROUND: Intestinal tract factors, especially intestinal ischemiareperfusion, can induce the injury of remote organ. Chinese herb, rhubarb,can clear oxygen free radical to promote the proliferation of beaker cell in intestinal mucous membrane, inhibit excessive multiplication of bacterium and endotoxin absorption in the intestinal tract, activate blood circulation and remove blood stasis, improve microcirculation and other ways to protect intestinal mucous membrane barrier, so as to prevent and treat pulmonary injury.OBJECTIVE: To observe the preventing and treating effect of rhubarb on intestinal ischemia/reperfusion-induced pulmonary injury and the effect of rhubarb on tumor necrosis factor and phospholipase A2 (PLA2).DESIGN: A randomized controlled observation.SETTING: Department of Emergency, Urumqi General Hospital of Lanzhou Military Area Command of Chinese PLA.MATERIALS: This experiment was carried out in the Second Military Medical University of Chinese PLA from February to July 2003. Totally 80SD rats were selected and randomly divided into intestinal ischemia/reperfusion group (n=24), sham operation group (n=46), treatment group (n=24) and normal saline group (n=16).METHODS: In the intestinal ischemia-reperfusion group, rats were fasted before operation. They were anesthetized and given a median abdominal incision. Superior mesenteric artery was isolated and occluded by vascular clamp without wound, and then the incision was sutured; 45 minutes later,vascular clamp was taken out to recover blood supply. For the treatment group, modeling was the same as that in the intestinal ischemia/reperfusion group, 600 mg/kg suspension of rhubarb extract was gastrointestinally perfused into the rats 30 minutes before recovering blood supply. For the normal saline group, modeling was the same as that in the intestinal ischemia/reperfusion group; same dosage of normal saline was gastrointestinally perfused into the rats 30 minutes before recovering blood supply. For the sham operation group, occlusion of superior mesenteric artery was omitted. Taking pathological change and 125I-labeled bovine serum albumin pulmonary uptake index as the index to evaluate pulmonary injury, TNF content and serum of pulmonary tissue and PLA2 activity of lung and intestinal tissue of animals in each group were measured respectively at different time points.MAIN OUTCOME MEASURES: 125I labeled bovine bovine serum albumin uptake index, tumor necrosis factor content of blood and pulmonary tissue, and PLA2 activity of serum, lung and intestinal tissue RESULTS: ① Pathological and morphological change of pulmonary tissue: There was no obvious abnormality in the sham operation group; In the intestinal ischemia-reperfusion group, 6 hours later, pulmonary interstitial edema, neutrophile infiltration appeared and alveolar edema was also found, and there were a little haemorrhage and exudation of fibrin. Only mild pulmonary interstitial edema and a small quantity of neutrophiles were found in the treatment group. ② Ultramicro-pathological change of pulmonary tissue: There was no obvious change in the sham operation group. In the intestinal ishcemia/reperfusion group, 6 hours later, pulmonary capillary endothelial cells were swelled and neutrophilic granulocyte leaked into pulmonary stroma and alveolar space. There were no above changes in the treatment group. ③ Change of tumor necrosis factor of pulmonary tissue in the sham operation group or treatment group (reperfusion for 30 minutes) was significantly lower than that in the intestinal ischemiareperfusion group (reperfusion for 30 minutes) (0.235±0.114,1.374±0.550,16.315±4.587,P ＜ 0.01). ④125I-BSA pulmonary uptake index in the treatment group was significantly lower than that in the intestinal ischemiareperfusion group and normal saline group (P ＜ 0.01), without significant difference in comparison with sham operation group (P ＞ 0.05).CONCLUSION: Early application of rhubarb is helpful to prevent and treat lung injury following small intestine ischemic reperfusion, so as to inhibit tissue disease course to deve1op multiple organ dysfunction syndrome,which might be implemented through inhibiting the release of TNF and PLA2 and other media.

OBJECTIVETo explore the influence of recombinant human growth hormone (rhGH) on the apoptosis and intestinal mucosal structure in severely scalded rats.

METHODSThirty male Wistar rats were randomly divided into three groups, i.e. control, scalding and rhGH groups. The rats in scalding and rhGH groups were inflicted with 25% TBSA III degree scalding on the back and immediately followed by intraperitoneal injection of dexamethasone (80 mg/kg). The scalded rats were administered with normal saline and rhGH (1.33 IU.kg(-1).d(-1)) since 2 postburn hours (PBHs), respectively in the last two groups. The changes of the apoptosis rate, the intestinal mucosal proliferative index (PI) and epithelial ultrastructure and the intestinal mucosal pathomorphology of the distal end of ileal mucosal tissue were observed on 30 and 96 PBHs.

RESULTSThe intestinal mucosa morphology and epithelia in scalding group were severely injured but were significantly ameliorated by rhGH to near those in control group. The PI in rhGH and scalding groups at 30 PBHs was evidently higher that that in control group (P < 0.05 - 0.01). But the PI exhibited no obvious difference between scalding and rhGH groups. While the PI in rhGH group at 96 PBHs was obviously higher than that in both scalding and control groups (P < 0.01). The intestinal mucosal epithelial apoptotic rate in scalding group was significantly higher than that in control group (P < 0.01), while that in rhGH group was evidently lower than that in scalding and control groups (P < 0.05 - 0.01).

CONCLUSIONrhGH could promote postburn intestinal mucosa epithelial proliferation in slow - action manner and inhibit intestinal mucosal epithelial apoptosis with rapid and obvious effects. As a result, the intestinal mucosal epithelial injury could be ameliorated by rhGH by means of its inhibiting roles and the normal morphological structure of intestinal mucosa was maintained ad hoc.

Animals ; Apoptosis ; Burns ; pathology ; Human Growth Hormone ; genetics ; pharmacology ; Intestinal Mucosa ; drug effects ; pathology ; Male ; Rats ; Rats, Wistar ; Recombinant Proteins ; pharmacology

Objective To enhance the cognition about the adult contagious atypical pneumonia for an expectation of earlier diagnosis, prevention and treatment.Methods We analyzed and summarized X-ray lung and clinical characteristics of 34 patients with contagious atypical pneumonias who were admitted to our hospital from Feb to April. 2003.Results X-ray findings of lung were characterized by mostly involving unilateral and presenting ill defined cloud or patches-form opacities. These lesions progressed and varied rapidly. The clinical manifestations were characterized by the onset of fever (34/34), mostly associated with systemic and joint aching pains (29/34) and dry coughs (29/34). Leucocyte counts showed normal or lower than normal. Patient with a continuing high fever might tend to develop ARDS (2/34). All the 34 patients recovered after combined therapies (anti-inflammation, anti-virus and promoting immunity ) and were discharged from hospital. The average in-hospital days were (10.6?4.2) days. Conclusion X-ray examination is the main method for the early diagnosis and observing state-variation. The predominant clinical features of this disease are fever, dry cough, aching pain in extremities, unconspicuous pulmonary signs as well as hemogram not rising, a continuing high fever may lead to the tendency of ARDS.