[Exosomes derived from bone marrow mesenchymal stem cells regulate NF-κB pathway and reduce lung ischemia-reperfusion injury in rats by miR-335]

This study aimed to investigate the effect of exosomes derived from bone marrow mesenchymal stem cells (BMSCs-EXO) on lung ischemia-reperfusion injury (IRI) in rats and to explore the role of miR-335. The model of rat lung IRI was established by clipping the hilum of left lung for 60 min and opening for 180 min. Forty Sprague-Dawley rats were randomly divided into sham group, IRI group, IRI+PBS group, IRI+EXO group, and IRI+miR-335 inhibitor EXO (IRI+inhibitor-EXO) group (n = 8). Rats in the sham group underwent thoracotomies without IRI. Rats in the IRI group were used to establish IRI model without any additional treatment. In the IRI+PBS, IRI+EXO, and IRI+inhibitor-EXO groups, the rats were used to establish IRI model and given PBS, EXO from BMSCs without any treatment, and EXO from BMSCs with miR-335 inhibitor treatment before reperfusion, respectively. Blood gases were analyzed during the experiment. Lung tissue wet/dry ratio (W/D), interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), myeloperoxidase (MPO), malondialdehyde (MDA), and superoxide dismutase (SOD) were measured at the end of reperfusion. Mitochondria were observed by electron microscopy and the Flameng scores were counted. Lung histopathology and apoptosis (TUNEL staining) were observed by light microscopy, and the lung injury scores (LIS) and apoptosis index (AI) were detected. The miR-335 expression was detected by RT-qPCR, and the expression of caspase-3, cleaved-caspase-3, caspase-9, cleaved-caspase-9, and NF-κB proteins were detected by Western blot at the end of reperfusion. The results showed that compared with the sham group, the oxygenation index, pH, and base excess (BE) were significantly lower in the IRI group and IRI+PBS group after reperfusion, whereas those indices were significantly higher in the IRI+EXO group than those in the IRI+PBS group (P < 0.05). Compared with the sham group, there were significant increases in W/D, IL-1β, TNF-α, MPO, MDA, LIS, AI, Flameng score, caspase-3, cleaved-caspase-3, caspase-9, and cleaved-caspase-9, however significant decreases in the SOD, miR-335 and NF-κB in the IRI group (P < 0.05). These indices in the IRI and IRI+PBS groups showed no significant differences. Compared with the IRI+PBS group, there were significant decreases in W/D, IL-1β, TNF-α, MPO, MDA, LIS, AI, Flameng score, caspase-3, cleaved-caspase-3, caspase-9, and cleaved-caspase-9, however significant increases in the SOD, miR-335 and NF-κB in the IRI+EXO group (P < 0.05). While, the changes of the above mentioned indices were reversed in the IRI+inhibitor-EXO group compared with IRI+EXO group, which were still better than those in the IRI+PBS group (P < 0.05). The results suggest that BMSCs-EXO could attenuate lung IRI in rats, activate NF-κB pathway, and maintain mitochondrial stability by up-regulating miR-335.

Stability analysis of Hadamard and Caputo-Hadamard fractional nonlinear systems without and with delay

This paper handles with the Hadamard and the Caputo-Hadamard fractional derivative and stability of related systems without and with delay. Firstly, the derivative inequalities are obtained, which is indispensable in applying the theorems derived in this paper. Then, for systems without delay, we get the stability results by using the Lyapunov direct method and for systems with delay, we explore two useful inequalities to verify the stability. Examples are presented with numerical simulations to illustrate the effectiveness of our results.

[Systematic evaluation of qualitative research on the real experience of burn patients during rehabilitation]

Objective: To systematically evaluate and integrate the real experience of burn patients during rehabilitation, and to provide theoretical guidance for the continual nursing care for burn patients. Methods: The systematic evaluation method was adopted. Databases including the China National Knowledge Internet, Wanfang Database, China Biology Medicine disc were retrieved with the search terms in Chinese version of "/, //, ////", and PubMed, Embase, CINAHL, PsycINFO, Cochrane Library were retrieved with the search terms of "burn/burns, rehabilitation/recovery/survivor/survive, experience/views/perceptions/, qualitative/phenomenon/interview/grounded theory". The qualitative studies on the real experience of burn patients during rehabilitation published from the establishment of each database to June 2020 were searched. The quality of the included studies was evaluated according to the quality evaluation criteria for qualitative research of the Joanna Briggs Institute Evidence-Based Health Care Center. The research country, research method, research object, research content, and main research result were summarized, and meta-synthesis of the research results was conducted with the aggregative integration method. Results: A total of 12 studies were included, and the quality of all the studies was grade B. The studies were conducted in 8 countries including Australia, Canada, Norway, etc., the research method mainly was phenomenological research method, and all the studies were focused on adult burn patients. A total of 46 specific themes were extracted with totally 10 new categories formed after summarization, and 3 integrated results were obtained as follows: burn patients suffered from both physical and psychological burdens, and their normal life was broken; burn patients gained post-traumatic growth and could actively adjust to cope with life difficulties; burn patients had multiple needs. Conclusions: Burn patients experience both physical and psychological pains during rehabilitation, so they long for multiple support from family and society. Medical staff, social groups, and family members should pay attention to the psychological experience and needs of burn patients with different characteristics during rehabilitation, and build a multi-directional social support system to help patients return to the society and rebuild their lives.

[Correlation of preoperative reconstruction of foramen ovale parameters and intraluminal balloon pressure during percutaneous balloon compression for trigeminal neuralgia]

Objective: To explore the relationship between the anatomic parameters of foramen ovale and intraluminal pressure during percutaneous balloon compression (PBC) in the treatment of primary trigeminal neuralgia. Methods: Twenty patients diagnosed with primary trigeminal neuralgia in the Department of Pain Medicine of the Third Xiangya Hospital, Central South University between November 2020 and April 2021 were enrolled. Three-dimensional (3D) high-resolution CT reconstruction of skull base was performed preoperatively to evaluate the parameters of foramen ovale. The intraluminal balloon pressure was continuously recorded during the PBC procedure. Correlation analysis was conducted between intraluminal pressure and foramen ovale parameters. Results: Eighteen patients had complete pain relief, 1 had obvious relief, and 1 had partial relief after PBC. The maximum cross-sectional length of the foramen ovale was (7.8±1.7) mm. The peak intraluminal pressure (P_M) during PBC was (194±27) kPa. The intraluminal pressure was (164±28) kPa at initial compression (P₀), and (135±20) kPa after compression for 120 seconds respectively. Correlation analysis showed that the P₀ was positively and significantly correlated with the length of foramen ovale (r=0.56, P<0.05), but not with the width of foramen ovale (r=0.24, P>0.05), the area of foramen ovale (r=0.36, P>0.05) and the degree of balloon filling (r=-0.09, P>0.05). Similarly, P₁₂₀ was significantly correlated with the length of foramen ovale (r=0.54, P<0.05). No significant correlation was observed between P₁₂₀ and the width of the foramen ovale (r=0.18, P>0.05), the area of the foramen ovale (r=0.28, P>0.05) or the width of balloon filling (r=-0.13, P>0.05). Conclusions: The length of foramen ovale correlates with the intraluminal pressure during PBC procedure in trigeminal neuralgia patients. Parameters of foramen ovale obtained via preoperative high-resolution CT reconstruction of skull base may provide reference for predicting targeted intraluminal balloon pressure during PBC.

Do distribution and expansion of exotic invasive Asteraceae plants relate to leaf construction cost in a man-made wetland?

Exotic species especially Asteraceae plants severely invade wetlands in Shenzhen Bay, an important part of the coast wetland in Guangdong-Hong Kong-Macau Bay Area, China. However, the reasons causing their expansion are unclear. The leaf traits and expansion indices of six invasive Asteraceae plants from the Overseas Chinese Town (OCT) wetland were studied and the results showed that nearly 45% of the total plant species (31 out of 69 species) in the OCT wetland, belonging to 15 families and 27 genera, were exotic invasive species. The expansion indices of six Asteraceae species negatively correlated with their leaf construction cost based on mass (CCM), caloric values and carbon concentration, but their relations with ash content were positive. Multiple linear regression analysis revealed that CCM was the most important factor affecting the expansion of an exotic species, indicating CCM may be an important reason causing the expansion of exotic species in coastal wetlands.

Is Laguncularia racemosa more invasive than Sonneratia apetala in northern Fujian, China in terms of leaf energetic cost?

Laguncularia racemosa and Sonneratia apetala are fast-growing exotic mangrove species in Southern China and widely used for afforestation. However, the invasiveness of the two exotic species is still unclear. We compared structural and physiological traits and energy-use related traits between L. racemosa and S. apetala, and with two natives (Kandelia obovata and Aegiceras corniculatum) in northern Fujian. Results showed that leaf construction cost based on mass (CCM) and caloric values of L. racemosa were significantly lower than S. apetala, and the two natives had highest CCM. Because lower CCM, L. racemosa grew faster with a taller height (4.83 m) and wider ground diameter circumference (40.03 cm) than S. apetala (4.43 m tall and 35.63 cm wide) and the two natives (2.42 m tall and 26.78 cm wide). These findings indicated that L. racemosa could be more invasive than S. apetala in mangrove forests in northern Fujian, China where it still grew well, which deserves more attention.

Efficiency and safety of ondansetron in preventing postanaesthesia shivering

Introduction Shivering is one of the most frequent complications of operation during the postanaesthesia period. Ondansetron has been proved to be valid in preventing postanaesthesia shivering (PAS) in several studies. However, its efficiency and safety are still disputable. We therefore performed an updated meta-analysis of randomised controlled trials (RCTs) for evaluation and to clarify this issue. Methods A literature search using the PubMed, Embase™ and Cochrane Library databases was performed (from inception to January 2015). RCTs that evaluated the efficiency and safety of ondansetron in the prevention of PAS were included in the meta-analysis. The primary outcome measure was incidence of PAS, and secondary outcomes included subgroup analysis and the side effects of ondansetron. Results A total of 8 RCTs containing 905 subjects were identified as suitable for this review. Compared with placebo, ondansetron was associated with a significant reduction of PAS (relative risk [RR]: 0.33, 95% confidence interval [CI]: 0.19-0.58, p=0.0001) while no difference was detected between ondansetron and pethidine (RR: 0.89, 95% CI: 0.41-1.94, p=0.78). There was no significant difference between ondansetron and placebo or pethidine in terms of risk of bradycardia but ondansetron was associated with a lower risk of hypotension (RR: 0.26, 95% CI: 0.08-0.79, p=0.020) than placebo. There was no difference in hypotension when ondansetron was compared with pethidine. Conclusions Ondansetron can prevent PAS effectively and reduce the risk of hypotension.

[Current status on management and needs related to education and training programs set for new employees at the provincial Centers for Disease Control and Prevention, in China]

OBJECTIVE

In order to understand the current management status on education/training and needs for training among new employees working at the provincial CDC in China during 2012-2014, so as to provide basis for setting up related programs at the CDC levels.

METHODS

Based on data gathered through questionnaire surveys run by CDCs from 32 provincial and 5 specifically-designated cities, microsoft excel was used to analyze the current status on management of education and training, for new employees.

RESULTS

There were 156 management staff members working on education and training programs in 36 CDCs, with 70% of them having received intermediate or higher levels of education. Large differences were seen on equipment of training hardware in different regions. There were 1 214 teaching staff with 66 percent in the fields or related professional areas on public health, in 2014. 5084 new employees conducted pre/post training programs, from 2012 to 2014 with funding as 750 thousand RMB Yuan. 99.5% of the new employees expressed the needs for further training while. 74% of the new staff members expecting a 2-5 day training program to be implemented. 79% of the new staff members claimed that practice as the most appropriate method for training.

CONCLUSIONS

Institutional programs set for education and training at the CDCs need to be clarified, with management team organized. It is important to provide more financial support on both hardware, software and human resources related to training programs which are set for new stuff members at all levels of CDCs.

Embolus-carried vascular endothelial cell growth factor 165 improves angiogenesis in thromboangiitis obliterans

We investigated neovasculization effects of embolus-carried human vascular endothelial cell growth factor 165 (VEGF165)-encoded adenovirus (Ad) vector in the hindlimbs of rats with thromboangiitis obliterans (TAO). Rats were equally divided into blank control (I), TAO model (II), embolus (III), Ad-VEGF165 intravascular treatment (IV), Ad-VEGF165 intramuscular treatment (V), and embolus-carried Ad-VEGF165 (VI) groups. After interventional treatment, the neovasculization effect of the test gene was observed using immunohistochemistry. At 1 week after administration, compared with group II, groups V and VI had significantly increased microvessel densities, but no significant difference was observed between groups V and VI. At 2 weeks, groups V and VI exhibited significantly increased microvessel densities. At 1 week after administration, compared with group II, both groups V and VI showed a significant difference in the ratio between the α-smooth muscle actin count and the muscle fiber count, whereas no significant difference was observed between them. At 2 weeks, groups V and VI also exhibited significant differences in these ratios compared with the other groups. We conclude that Ad-VEGF165 promotes neovasculization in ischemic limbs. Embolus-carried Ad- VEGF165 had the most pronounced effect.

Curative effect of combined lamivudine, adefovir dipivoxil, and stem cell transplantation on decompensated hepatitis B cirrhosis

This study assessed the clinical efficacy of lamivudine and adefovir dipivoxil combined with autologous bone marrow stem cell transplantation as treatment for patients with hepatitis B and decompensated liver cirrhosis. In total, 77 patients with hepatitis B and decompensated liver cirrhosis were randomly divided into two groups. Under general symptomatic and supportive treatment, the patients in group A (37 cases) were treated with lamivudine and adefovir dipivoxil, whereas those in group B (40 cases) were treated with autologous bone marrow stem cell transplantation in combination with lamivudine and adefovir dipivoxil. After 4 weeks of treatment, the liver function indicators and clinical signs and symptoms of the patients in group B improved more significantly than those of patients in group A. Lamivudine and adefovir dipivoxil in combination with autologous bone marrow stem cell transplantation effectively prevented hepatitis B virus infection and bone marrow stem cell damage. This combination treatment facilitates the differentiation of bone marrow stem cells into normal liver cells to restore liver structure and improve liver function, thereby improving the quality of life of patients.

Hypercapnic acidosis confers antioxidant and anti-apoptosis effects against ventilator-induced lung injury

Hypercapnic acidosis may attenuate ventilator-induced lung oxidative stress injury and alveolar cell apoptosis, but the underlying mechanisms are poorly understood. We examined the effects of hypercapnic acidosis on the role of apoptosis signal-regulating kinase 1 (ASK1), which activates the c-Jun N-terminal kinase (JNK) and p38 cascade in both apoptosis and oxidative reactions, in high-pressure ventilation stimulated rat lungs. Rats were ventilated with a peak inspiratory pressure (PIP) of 30 cmH2O for 4 h and randomly given FiCO2 to achieve normocapnia (PaCO2 at 35-45 mm Hg) or hypercapnia (PaCO2 at 80-100 mm Hg); normally ventilated rats with PIP of 15 cmH2O were used as controls. Lung injury was quantified by gas exchange, microvascular leaks, histology, levels of inflammatory cytokines, and pulmonary oxidative reactions. Apoptosis through the ASK1-JNK/p38 mitogen-activated protein kinase (MAPK) cascade in type II alveolar epithelial cells (AECIIs) were evaluated by examination of caspase-3 activation. The results showed that injurious ventilation caused significant lung injury, including deteriorative oxygenation, changes of histology, and the release of inflammatory cytokines. In addition, the high-pressure mechanical stretch also induced apoptosis and caspase-3 activation in the AECIIs. Hypercapnia attenuated these responses, suppressing the ASK1 signal pathways with its downstream kinase phosphorylation of p38 MAPK and JNK, and caspase-3 activation. Thus, hypercapnia can attenuate cell apoptosis and oxidative stress damage in rat lungs during injurious ventilation, at least in part, due to the suppression of the ASK1-JNK/p38 MAPK pathways.

High preoparative levels of serum periostin are associated with poor prognosis in patients with hepatocellular carcinoma after hepatectomy

AIMS

Periostin (POSTN) is implicated in cancer development and progression. The aim of this study was to evaluate the diagnostic and prognostic significance of serum POSTN in patients with hepatocellular carcinoma (HCC) receiving curative surgery.

METHODS

Enzyme-linked immunosorbent assay was performed to determine serum POSTN levels in 69 healthy volunteers, 30 patients with hepatolithiasis, 27 patients with cirrhosis, and 56 HCC patients. The relationships between serum POSTN and clinicopathologic features were analyzed. Receiver operating characteristics analysis was used to calculate diagnostic accuracy of serum POSTN, serum alpha-fetoprotein (AFP), and their combination. The prognostic impact of serum POSTN on overall survival (OS) and relapse-free survival (RFS) was also investigated.

RESULTS

The median serum POSTN level was significantly (P < 0.05) increased in HCC patients, compared to healthy controls, patients with hepatolithiasis, and patients with liver cirrhosis. Elevated serum POSTN was only significantly associated with Edmondson grade (P = 0.007). The combination of serum POSTN and AFP had a markedly higher area under the curve (0.805 (95% confidence interval [CI]: 0.677-0.932)) than POSTN (0.582 (95% CI: 0.427-0.736)) or AFP (0.655 (95% CI: 0.504-0.806)) alone. Kaplan-Meier analysis indicated that elevated serum POSTN was associated with OS (P = 0.031) and RFS (P = 0.027). Moreover, multivariate analysis revealed elevated serum POSTN as an independent poor prognostic marker for OS and RFS.

CONCLUSIONS

Preoperative serum POSTN has limited diagnostic value in distinguishing HCC from non-malignant liver diseases, but serves as independent prognostic biomarker in HCC patients.

Carbon monoxide inhalation ameliorates conditions of lung grafts from rat brain death donors

BACKGROUND

Successful lung transplantation has been limited by the scarcity of donors. Brain death (BD) donors are major source of lung transplantation. Whereas BD process induces acute lung injury and aggravates lung ischemia reperfusion injury. Carbon monoxide (CO) inhalation at 50-500 parts per million (ppm) can ameliorate lung injury in several models. We examined in rats whether CO inhalation in BD donor would show favorable effects on lung grafts.

METHODS

Rats were randomly divided into 4 groups. In sham group, donor rats received insertion of a balloon catheter into the cranial cavity, but the balloon was not inflated. In BD-only group, donor rats were ventilated with 40% oxygen after BD confirmation. In BD+CO250 and BD+CO500 groups, donor rats inhaled, after BD confirmation, 250 ppm or 500 ppm CO for 120 minutes prior to lung procurement, and orthotopic lung transplantation was performed. The rats were sacrificed 120 minutes after the lung transplantation by exsanguination, and their blood and lung graft samples were obtained. A total of 8 rats fulfilling the criteria were included in each group.

RESULTS

The inhalation decreased the severity of lung injury in grafts from BD donors checked by histological examination. CO pretreatment reversed the aggravation of PaO2/FiO2 in recipients from BD donors. The CO inhalation down-regulated pro-inflammatory cytokines (TNF-alpha, IL-6) along with the increase of anti-inflammatory cytokine (IL-10) in recipient serum, and inhibited the activity of myeloperoxidase in grafts tissue. The inhalation significantly decreased cell apoptosis in lung grafts, inhibiting mRNA and protein expression of intercellular adhesion molecule-1 (ICAM-1) and caspase-3 in lung grafts. Further, the inhalation activated phosphorylation of p38 expression and inhibited phosphorylation of anti-extracellular signal-regulated kinase (ERK) expression in lung grafts. The effects of CO at 500 ppm were greater than those at 250 ppm.

CONCLUSIONS

CO exerts potent protective effects on lung grafts from BD donor, exhibiting anti-inflammatory and anti-apoptosis functions by modulating the mitogen-activated protein kinase (MAPK) signal transduction.

Identification of the epitopes on HCV core protein recognized by HLA-A2 restricted cytotoxic T lymphocytes

AIM: To identify hepatitis C virus (HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL).

METHODS: Utilizing the method of computer prediction followed by a 4 h ⁵¹Cr release assay confirmation.

RESULTS: The results showed that peripheral blood mononuclear cells (PBMC) obtained from two HLA-A2 positive donors who were infected with HCV could lyse autologous target cells labeled with peptide “ALAHGVRAL (core 150-158)”. The rates of specific lysis of the cells from the two donors were 37.5% and 15.8%, respectively. Blocking of the CTL response with anti-CD4 mAb caused no significant decrease of the specific lysis. But blocking of CTL response with anti-CD8 mAb could abolish the lysis.

CONCLUSION: The peptide (core 150-158) is the candidate epitope recognized by HLA-A2 restricted CTL.

Oxidative scission of a Mo-Mo quadruple bond

Two compounds containing the cations Mo2(DPhIP)4n+, n = 1 or 2 and DPhIP = the anion of 2,6-diphenyliminopiperidine, have been obtained by oxidation of the quadruply-bonded Mo2(DPhIP)4 species. The first oxidation process conserves the structure but results in a slight increase of the Mo-Mo distance from 2.114(1) to 2.136(2) A in [Mo2(DPhIP)4](PF6).2CH2Cl2 (1.2CH2Cl2). However, the second oxidation process breaks the dimolybdenum bond, giving a bioctahedral complex, [Mo2(DPhIP)4](BF4)2.5CH3CN.Et2O (2.5CH3CN.Et2O), with Mo...Mo separation of 2.9954(7) A. Crystallographic data for 1.2CH2Cl2 are space group C2/c, a = 17.1891(9) A, b = 17.807(1) A, c = 24.210(2) A, beta = 106.403(4) degrees, Z = 4; for 2.5CH3CN.Et2O, space group P2(1)/n, a = 16.523(5) A, b = 27.418(5) A, c = 18.163(3) A, beta = 93.48(2) degrees, Z = 4.

Linear trichromium complexes with the anion of 2,6-di(phenylimino)piperidine

The anion of 2,6-di(phenylimino)piperidine (DPhIP) has been found to support linear chains of three metal atoms. Three new compounds, [Cr3(DPhIP)4Cl]Cl.(1).5CH2Cl2.0.5H2O (1.1.5CH2Cl2.0.5H2O), [Cr3(DPhIP)4(CH3CN)]- (PF6)2.H2O.4CH3CN (2.H2O.4CH3CN), and [Cr3(DPhIP)4(F)(CH3CN)](BF4)2.5CH3CN (3.5CH3CN), have been synthesized and characterized by X-ray crystallography. Compound 1 has a linear chain of three chromium atoms arranged in an unsymmetrical fashion, with two of them forming a quadruply bonded unit (Cr-Cr distance 1.932(2) A) and the third being a non-metal-metal-bound 5-coordinate unit (Cr...Cr distance 2.659(2) A). The fifth coordination site is occupied by a chloride ion, and another chloride ion is located in the interstices of the crystal. The trimetal unit in compound 2 is structurally similar to that in compound 1 except that the axial ligand in 2 is a CH3CN molecule. Compound 3 is an oxidation product prepared by reaction of 1 with AgBF4. Here, a square pyramidal CrIII unit, FCrN4, and a Cr-Cr quadruply bonded (Cr-Cr distance 1.968(2) A) unit, with an axially coordinated acetonitrile molecule, form the trichromium chain. The CrIII...CrII separation of 2.594(2) A in 3 is too long to be considered a bonding interaction.

Heteronuclear chains of four metal atoms including one quadruply bonded dimetal unit. Dichromium and dimolybdenum compounds with appended copper(I) atoms

It is shown that the M2(DPhIP)4 molecules (M = Cr, Mo; HDPhIP = 2,6-di(phenylimino)piperidine) can each capture two CuI atoms to form molecules with linear Cu...M[symbol: see text] M...Cu chains. In these chains the CuI atoms have only weak interactions with the M atoms (Cr...Cu = 2.628 A; Mo...Cu = 2.615 A) even though their introduction causes marked decreases in the M[symbol: see text]M distances (from 2.265 to 1.906 A for Cr and from 2.114 to 2.078 A for Mo). These seemingly contradictory facts are explained by noting that in the M2(DPhIP)4 molecules there are strong destabilizing (to the M[symbol: see text]M bonds) donor interactions of the dangling nitrogen atoms with the pi* orbitals. When these are eliminated by the introduction of the CuI atoms, the M[symbol: see text]M bonds become stronger and shorter.

Preconditioning improves myocardial preservation in patients undergoing open heart operations

BACKGROUND

Our previous work has shown that preconditioning can promote the recovery of cardiac function in patients having an open heart procedure. Because preconditioning is regarded as the most powerful form of endogenous myocardial protection, we tested the hypothesis that preconditioning protects against myocardial ischemia-reperfusion injury in patients undergoing prolonged cold crystalloid cardioplegic arrest.

METHODS

Thirty patients who had rheumatic heart disease and required both aortic and mitral valve replacement were studied. Patients were randomly divided into two equal groups. Preconditioning was accomplished using two cycles of 2-minute occlusion of the vena cava and aorta followed by 3 minutes of reperfusion under cardiopulmonary bypass. All hearts were arrested with 4 degrees C St. Thomas' Hospital cardioplegic solution. Myocardial protective effects were assessed by changes in myocardial levels of adenosine triphosphate, electrocardiographic activity, leakage of myocardial enzymes, and myocardial contractility.

RESULTS

The adenosine triphosphate content in ischemic myocardium was higher in the preconditioning group than in the control group (p < 0.05 90 minutes after ischemia), and there was a significant reduction in release of the myocardial-specific isoenzyme of creatine kinase in the preconditioning group. Preconditioning improved the recovery of myocardial contractility (first derivative of left ventricular developed pressure, 1,490 +/- 102 mm Hg/s versus 1,250 +/- 97 mm Hg/s 30 minutes after reperfusion; p < 0.05), and there was also a protective effect on electrocardiographic activity.

CONCLUSIONS

Our results suggest that ischemic preconditioning protects the myocardium in humans from the severe ischemia-reperfusion injury produced after prolonged arrest with cold crystalloid cardioplegia.

[Changes in T-lymphocyte subsets of peripheral blood in unexplained habitual abortion]

T-lymphocyte subsets of peripheral blood were examined by flow cytometry (FCM) in 20 cases of unexplained habitual abortion (UHA) before and after active immunization treatment, with 10 normal pregnant (NP) women and 20 normal nonpregnant (NNp) women as control.

THE RESULTS

there was no difference in the percentage of CD3 cells between the UHA cases and NNP. Before immunization the percentage of CD8 cells was significantly lower (P < 0.001) and the ratio of CD4/CD8 was increased (P < 0.05) in UHA as compared with the NNP. However, after immunization, the percentage of CD8 cells greatly increased (P < 0.05) and CD4/CD8 ratio decreased significantly (P < 0.05) nearly to that of NP. These findings suggest that: (1) the increase of CD4/CD8 ratio due to the decreasing CD8 cells is the underlying immunomechanism of UHA; (2) immunization may induce the proliferation of CD8 cells and the lowering of CD4/CD8 ratio. Therefore, CD8 cells might play an important role in maintaining the balance of fetal-maternal immunological relationship; (3) the ratio of CD4/CD8 may served as parameter for observing the clinical efficacy of immunization therapy.

Surgical treatment of solitary peripheral pulmonary artery aneurysm associated with ventricular septal defect

In the case presented a solitary peripheral pulmonary artery aneurysm occurred in a woman with ventricular septal defect (VSD). During the operation of repairing the VSD under cardiopulmonary bypass, the pulmonary artery aneurysm (PAA) suddenly ruptured into the bronchus and a large amount of air entered the pulmonary artery and right ventricle when the anesthetist inflated the lungs. The air in the right ventricle could not be evacuated completely, so we had to remove the lobe where the aneurysm was located. The operation was successful and the postoperative course was uncomplicated.

[Traumatic diaphragmatic injury and hernia]

31 cases of traumatic diaphragmatic injury were treated in our department from Jan. 1977 to Jan. 1986. Among them, 18 were caused by blunt trauma and 13 by penetrated wound. 17 of the cases accompanied with diaphragmatic hernia. 80% of the cases (25/31) were complicated trauma. As a result, 28 of them recovered with only 3 died. The authors described the mechanism and characteristics of diaphragmatic trauma as well as its diagnosis and treatment.