Synthesis, biological and molecular docking studies of pyrimidine-derived bioactive Schiff bases.

Pyrimidine which is an important constituent of the genetic material of deoxyribonucleic acid, is identified with a large number of biological activities. Based on this, pyrimidine-derived Schiff bases (1-6) of hydroxy-1-naphthaldehyde were synthesized by using the condensation method. In addition, the molecular docking studies against topoisomerase II DNA gyrase, human hematopoietic cell kinase, urate oxidase from Aspergillus flavus, and cyclin-dependent kinase 8 to explore the antibacterial, antioxidant, antifungal, and anticancer properties respectively and binding affinities through bioinformatics approaches to determine the interaction among active molecules with the receptor. Hence, the computational docking analyses identified that all synthesized pyrimidine Schiff bases (1-6) are active and exhibited better binding affinities as compared to the standard drugs. Furthermore, all the prepared materials were characterized by using nuclear magnetic resonance, infrared, and elemental analysis. Additionally, the phase-transition and thermal decomposition temperatures were determined by differential scanning calorimetry and thermo-gravimetric analysis measurements. Moreover, the structures of pyrimidine-derived Schiff bases 1, 2, 3, 4, and 5 were also confirmed by the X-ray single-crystal diffraction technique. The pyrimidine-derived Schiff bases 5 possess significant antibacterial, antioxidant, antifungal, and anticancer agent properties which confirms its promising biological activities over standard drugs.

Contemplating the necessity of surgical treatment for posterior lenticonus: a case report.

BACKGROUND: Posterior lenticonus is an uncommon congenital abnormality that causes a progressive, localized spherical or conical bulging of the posterior capsular membrane, resulting in an abnormal shape of the lens. CASE PRESENTATION: A 13-year-old girl presented with ametropia in both eyes. After mydriasis, examination revealed an oval bubble-shaped alteration with a distinct boundary above the temporal region on the center of the posterior capsule of her left lens. The subcortical region surrounding the alteration appeared feathery and turbid. The patient had no history of trauma or family history of visual impairment. Systemic investigations were normal. A thorough eye examination was performed, which included optometry, ultrasound biomicroscopy, ocular B-Scan, and anterior segment optical coherence, to assess the disease. The patient was diagnosed with posterior lenticonus in the left eye, as well as ametropia and anisometropia in both eyes. Conservative treatment was initiated since the patient's current best corrected visual acuity was good, and regular monitoring of the condition's progression was scheduled. CONCLUSIONS: This case report presents a rare instance of posterior lenticonus. The findings of this report raise new considerations regarding the necessity of surgical intervention for this condition.

Splicing oxygen-rich multidentate ligands and characteristic metals to construct flame colorants: abundant structures and attractive colors.

Tetranitroethane (TNE), an energetic compound with high-nitrogen (N%, 26.7%) and oxygen (O%, 60.9%) content, is deprotonated by alkali and alkaline earth metal bases to form the corresponding metal salts of TNE which are characterized by FT-IR spectroscopy, elemental analysis, and single crystal X-ray diffraction. All the prepared energetic metal salts show excellent thermal stabilities, and the decomposition temperatures of EP-3, EP-4, and EP-5 are higher than 250 °C, due to the numerous coordination bonds of the complexes. Furthermore, the energy of formation of the nitrogen-rich salts were calculated utilizing heat of combustion. The detonation performances were calculated with the EXPLO5 software, and the impact and friction sensitivities were determined. EP-7 shows excellent energy performance (P = 30.0 GPa, VD = 8436 m s-1). EP-3, EP-4, EP-5, and EP-8 are more sensitive to mechanical stimulation. These alkali and alkaline earth metal salts of TNE show good monochromaticity by atomic emission spectroscopy (visible light), and may be used as potential flame colorants in pyrotechnics.

Synthesis, Crystal Structure, and Characterization of Energetic Salts Based on 3,5-Diamino-4H-Pyrazol-4-One Oxime.

In order to broaden the study of energetic cations, a cation 3,5-diamino-4H-pyrazol-4-one oxime (DAPO) with good thermal stability was proposed, and its three salts were synthesized by a simple and efficient method. The structures of the three salts were verified by infrared spectroscopy, mass spectrometry, elemental analysis, and single crystal X-ray diffraction. The thermal stabilities of the three salts were verified by differential scanning calorimetry and thermos-gravimetric analysis. DAPO-based energetic salts are analysed using a variety of theoretical techniques, such as 2D fingerprint, Hirshfeld surface, and non-covalent interaction. Among them, the energy properties of perchlorate (DAPOP) and picrate (DAPOT) were determined by EXPLO5 program combined with the measured density and enthalpy of formation. These compounds have high density, acceptable detonation performance, good thermal stability, and satisfactory sensitivity. The intermolecular interactions of the four compounds were studied by Hirshfeld surface and non-covalent interactions, indicating that hydrogen bonds and π-π stacking interactions are the reasons for the extracellular properties of perchlorate (DAPOP) and picrate (DAPOT), indicating that DAPO is an optional nitrogen-rich cation for the design and synthesis of novel energetic materials with excellent properties.

Energetic bimetallic complexes as catalysts affect the thermal decomposition of ammonium perchlorate.

Two bimetallic complexes of 4-hydroxy-3,5-dinitropyrazole, [K2Mn(DNPO)2(H2O)4]n·2H2O (BMEP-1) and [K2Zn(DNPO)2(H2O)6]n (BMEP-2), were synthesized and characterized by IR spectroscopy and elemental analysis. The crystal structures of BMEP-1 and BMEP-2 were determined by single-crystal X-ray diffraction. It is noteworthy that these complexes presented different metal-organic frameworks. The thermal behaviors of BMEP-1 and BMEP-2 were investigated by differential scanning calorimetry and thermogravimetric analysis measurements. These bimetallic complexes exhibited high thermal stability (348.0 °C and 331.0 °C) due to their large coordination bonds and three-dimensional interconnected structure. The catalytic performances of BMEP-1 and BMEP-2 on the thermal decomposition of ammonium perchlorate were investigated by TGA-DSC, TGA-FTIR, and non-isothermal kinetic analyses. The results showed that BMEP-1 and BMEP-2 exhibited excellent catalytic performance in the thermal decomposition of ammonium perchlorate. Notably, there was only a single exothermic peak at 302.6 °C and 318.6 °C, and the activation energy values of ammonium perchlorate decreased to 123.88 kJ mol-1 and 128.43 kJ mol-1, respectively. TGA-FTIR results showed that BMEP-1 and BMEP-2, as effective components of catalysis, will promote the production of H2O, N2O, NO2, and HCl in advance, during the thermal decomposition of ammonium perchlorate. BMEP-1 and BMEP-2 are expected to be two candidate additives for the catalytic decomposition of ammonium perchlorate in composite solid propellants.

Synthesis and characterization of promising insensitive energetic salts based on 3-amino-5-hydrazinopyrazole.

The development of green energetic materials is based on environmental friendliness, safety and performance improvement. It is of great significance to design and synthesize new nitrogen rich salts for a new generation of green energetic materials. In the present work, a series of 3-amino-5-hydrazinopyrazole energetic salts comprising energetic anions were synthesized and were characterized using elemental analysis, IR spectroscopy and differential scanning calorimetry (DSC). Compounds 1-5 were further confirmed by single crystal X-ray diffraction and the sensitivities were measured by the standard BAM methods. Additionally, the structure-property relationship was elucidated from the experimental results and theoretical calculations. Energetic salts of 2 and 5 exhibited high heat of formation (5, 1160.06 kJ mol-1), high decomposition temperature (2, 172 °C; 5, 186 °C), excellent detonation performance (2, Dv, 9076 m s-1, P 34.1 GPa; 5, Dv, 8974 m s-1, P 31.9 GPa), moderate sensitivity towards outer stimuli and high nitrogen contents (2, 41.03%; 5, 63.84%). This work increases future prospects for the design of insensitive and novel high-energy green energetic material.

Untreated Prior Pulmonary Tuberculosis Adversely Affects Pregnancy Outcomes in Infertile Women Undergoing in vitro Fertilization and Embryo Transfer: A Large Retrospective Cohort Study.

OBJECTIVE: Prior pulmonary tuberculosis (PTB) on chest X-ray (CXR) was commonly found in infertile patients receiving examinations before in vitro fertilization and embryo transfer (IVF-ET). It was unclear whether untreated PTB would affect pregnancy outcomes after IVF-ET. METHOD: We conducted a retrospective cohort study of 14,254 infertile patients who had received IVF-ET at Peking University Third Hospital in 2017. Prior PTB was defined as the presence of signs suggestive of old or inactive PTB on CXR, with or without a clinical TB history. Patients who had prior PTB on CXR but had not received a clinical diagnosis and anti-TB therapy were included for analysis. Live birth, clinical pregnancy, and miscarriage rates were compared between the untreated PTB and non-PTB groups. RESULTS: The untreated PTB group had significantly lower clinical pregnancy (31.7% vs. 38.1%) and live birth (23.8% vs. 30.6%) rates than the non-PTB group (both P < 0.001). Multivariate analysis revealed that untreated PTB was a risk factor for decreased live birth rate [odds ratio ( OR), 0.80; 95% confidence interval ( CI), 0.66-0.98; P = 0.028] in all patients and for increased miscarriage ( OR, 4.19; 95% CI, 1.69-10.39; P = 0.002) and decreased live birth ( OR, 0.45; 95% CI, 0.24-0.83; P = 0.011) rates in patients with unexplained infertility. CONCLUSIONS: Untreated PTB was associated with adverse pregnancy outcomes after IVF-ET, especially in patients with unexplained infertility, highlighting the clinical significance of PTB in this specific patient population.

[Antithrombotic effects of recombinant hirudin in mice and its mechanism].

OBJECTIVE: To investigate the antithrombotic effects of recombinant hirudin and its mechanism. METHODS: Sixty male Kunming mice were randomly divided into 6 group (n=10):control group, model group, aspirin (25 mg/kg) group, recombinant hirudinlow, middle and high dose (0.05, 0.1, 0.2 mg/kg) groups.Except mice in control group, 2.5 mg/kg carrageenan was injected intraperitoneallyto mice in the other groups to produce thrombosis on the mice tail. The mice in aspirin group were administrated intraperitoneally 25 mg/kg aspirin, the mice in recombinant hirudinlow, middle and high dose groups were administrated intraperitoneally 0.05, 0.1, 0.2 mg/kg combinanthirudin, the mice in control group and model group were administrated intraperitoneallynormal saline at the same volume respectively at 24 h, 0.5 h before injecting carrageenan and 24 h after injecting carrageenan. The black tail length of mice and the incidence of black tail were observed at 48h after injection of carrageenan; prothrombin time (PT), activated partial thromboplastin time (APTT), tissue plasminogen activator (t-PA), type-1 plasminogen activator inhibitor (PAI-1), 6-keto-PGF1α, and thromboxane B2 (TXB2) level in mice plasma were determined. RESULTS: As compared with control group, the mice in model group presented tail thrombosis; PT level in plasma was significantly shortened (P<0.01), PAI-1 and TXB2levels in plasma were significantly increased (P<0.01), while the t-PA and 6-keto-PGF1α levels in plasma in model group were significantly decreased (P<0.01). As compared with model group, the thrombus length in the tail was significantly shortened (P<0.05, P<0.01), PT level was obviously prolonged (P<0.01), and the plasma levels of PAI-1 and TXB2 were significantly decreased (P<0.01), while the plasma levels of t-PA and 6-keto-PGF1α were significantly increased (P<0.01)in the mice of recombinant hirudin low dose, middle dose, high dose groups and aspirin group. As compared with aspirin group, the thrombus length in the tail was significantly increased (P<0.05), PT level was obviously shortened (P<0.01), and the plasma levels of PAI-1 and TXB2 were significantly increased (P<0.01)in the mice of recombinant hirudin low dose group; the plasma level of 6-keto-PGF1α was significantly decreased (P<0.01, P<0.05) in the mice of recombinant hirudin low dose and middle dose groups; the plasma levels of PAI-1 and TXB2 were significantly increased (P<0.01, P<0.05)in the mice of recombinant hirudin middle dose group. CONCLUSIONS: The recombinant hirudin can fight against thrombosis, its antithrombotic mechanisms may be related to its influence on the exogenous coagulation system and the promotion of fibrinolysis function.

Vitamin D deficiency and the risk of tuberculosis: a meta-analysis.

BACKGROUND AND AIM: To conduct meta-analyses of all published studies on various aspects of association between vitamin D and tuberculosis (TB). METHODS: PubMed and Web of Knowledge were searched for all properly controlled studies on vitamin D and TB. Pooled odds ratio, mean difference or standardized mean difference, and its corresponding 95% confidence interval were calculated with the Cochrane Review Manager 5.3. RESULTS: A significantly lower vitamin D level was found in TB patients vs controls; vitamin D deficiency (VDD) was associated with an increased risk of TB, although such an association was lacking in the African population and in the human immunodeficiency virus-infected African population. A significantly lower vitamin D level was found in human immunodeficiency virus-TB-coinfected African patients receiving antiretroviral treatment who developed TB-associated immune reconstitution inflammatory syndrome vs those who did not develop TB-associated immune reconstitution inflammatory syndrome. VDD was associated with an increased risk of developing active TB in those subjects with latent TB infection and with an increased risk of tuberculin skin test conversion/TB infection conversion, and the trend toward a lower vitamin D level in active TB patients vs latent TB infection subjects did not reach statistical significance, indicating that VDD was more likely a risk factor than a consequence of TB. This concept was further strengthened by our result that anti-TB treatment did not affect vitamin D level in TB patients receiving the treatment. CONCLUSION: Our analyses revealed an association between vitamin D and TB. VDD is more likely a risk factor for TB than its consequence. More studies are needed to determine whether vitamin D supplementation is beneficial to TB prevention and treatment.

A decision-tree model for predicting extubation outcome in elderly patients after a successful spontaneous breathing trial.

BACKGROUND: The commonly used single tests, based on a 1-time measurement of a physiologic variable, are often poorly predictive of tracheal extubation outcome because they examine only a single aspect of physiological function that affects the extubation outcome. We hypothesized that the construction of a decision-tree model, which includes multiple variables and considers the changes of these variables, may more accurately predict successful extubation. METHODS: This was a prospective observational study. From 2007 to 2008, 113 elderly patients in the medical intensive care unit on ventilation for >48 hours were enrolled. All patients underwent a 60-minute spontaneous breathing trial (SBT) [positive end-expiratory pressure of 5 cm H(2)O; automatic tube compensation, 100%]. Patients tolerating the trial were extubated immediately. The mouth occlusion pressure (P(0.1)), rapid shallow breathing index (RSBI,) and their combination (P(0.1) × RSBI) were recorded at the first, 30th, and 60th minute of the SBT. The changes in RSBI, which were determined at the 30th and 60th minute of the SBT (ΔRSBI30, ΔRSBI60), were assessed as the ratio (of RSBI30 or RSBI60) to RSBI at the first minute of the SBT. RESULTS: Twenty-two patients (19.5%) failed the SBT and were not included in the analysis, and 91 tolerated the trial and were extubated. At 48 hours, 73 (80.2%) remained extubated (successful extubation), and 18 (19.8%) required reintubation (extubation failure). Although theΔRSBI(30) was significantly higher in the extubation failure patients (118% ± 34%) than that in the successful extubation patients (93% ± 35%, P = 0.01), the receiver operating characteristic (ROC) analysis demonstrated that this index, with the threshold of <98%, presented poor performance in predicting successful extubation with area under the ROC curve (AUC) of only 0.76. The classification and regression-tree analysis selected 3 variables (P(0.1) × RSBI(30), RSBI(1), ΔRSBI(30)) and began with P(0.1) × RSBI(30). For patients with P(0.1) × RSBI-(30) >474 cmH(2)O*breaths/min/L, ΔRSBI(30) >98% defined a group including all failure patients but no success patients, whereas ΔRSBI(30) ≤98% included all success patients with no failure patients. For patients with P(0.1) × RSBI(30) ≤474 cm H(2)O*breaths/min/L, the combination of both a P(0.1) × RSBI(30) >328 cm H(2)O*breaths/min/L and RSBI(1) >112 breaths/min/L also defined a group including all success patients but no failure patients. Indeed, the diagnostic accuracy (DA) of the tree model, which was 89.1% with only the P(0.1) × RSBI(30) included, increased to 94.5% when both the P(0.1) × RSBI(30) and ▵RSBI(30) were included. The final tree model with the inclusion of all 3 discriminators could capture the successful extubation with diagnostic accuracy of 96.7%, AUC of 0.94 (95% confidence interval [CI], 0.87 to 0.98). CONCLUSION: If the current tree model is confirmed by a prospective study with a larger sample size, it would be useful in guiding physicians making extubation decisions in elderly medical intensive care unit patients.

[Radar radiation damages sperm quality].

OBJECTIVE: To study the effects of radar radiation on sperm quality. METHODS: A total of 348 infertile seamen were divided into 4 experimental groups according to their different lengths of exposure to radar radiation: Group 1 (n = 128) exposed for 12-36 months, Group 2 (n = 58) 37-72 m, Group 3 (n = 47) 73-108 m, Group 4 (n = 19) 109 m or more and Group 5 (n = 96) 48 m or more but free from the exposure for 6 months by then. Another 35 non-marine normal males were recruited as Control Group 1, and the first four experimental groups (n = 252) were taken as Control Group 2. Semen samples were collected from the subjects and analyzed statistically. RESULTS: Compared with the normal control, sperm concentration, sperm motility and the percentage of grade a sperm were significantly lower (P < 0.01), and the percentages of grade d and abnormal sperm significantly higher (P < 0.01) in the experimental groups. In Group 5, obvious recovery was noted in sperm morphology (P < 0.01) and motility (P < 0.05), but significant differences were seen with the normal control group in sperm concentration (P < 0.05), sperm motility and the percentage of grade a and b sperm and that of abnormal sperm (P < 0. 01). CONCLUSION: Radar radiation damages sperm quality, as shown in the reduction of sperm motility and elevation of sperm abnormality. Cease from the exposure may effect an easy recovery in sperm morphology.

[The relationship between sputum eosinophils and responses to treatment of inhaled glucocorticoids in patients with persistent asthma].

OBJECTIVE: To evaluate the treatment responses of asthmatics with and without sputum eosinophilia to inhaled glucocorticoids, and therefore to verify whether low sputum eosinophils predict poor response to treatment with inhaled glucocorticoids. METHODS: Forty-two symptomatic asthmatic patients, who had not received glucocorticoid therapy in the 3 months preceding the study, were examined before and 1 month and 3 months after treatment with inhaled glucocorticoids. At each visit, all patients underwent spirometry, symptom scoring and sputum induction. The level of eosinophil cationic protein (ECP) in the sputum supernatants was measured by radioimmunoassay. The patients were divided into 2 groups according to sputum eosinophil (EOS) percentages, an EOS group (EOS > 3%) and a non-EOS group (EOS < 3%). The response to inhaled glucocorticoid therapy (as measured by symptom scores and FEV(1)% pred) and the changes of sputum measurements were compared between the 2 groups. RESULTS: In the EOS group, the baseline EOS [0.080 (0.063 - 0.178)] and ECP level [(324 +/- 149) microg/L] were significantly higher than those of the non-EOS group [0.017 (0.006 - 0.021) and (152 +/- 68) microg/L, respectively, t = 4.40, 3.33, both, all P < 0.01]. Baseline FEV(1), FEV(1)% pred and symptom scores were not different between the 2 groups [EOS group: (1.98 +/- 0.67) L, (65 +/- 20)%, 7.0 (5.0 - 10.0), non-EOS group: (2.07 +/- 1.05) L, (66 +/- 27)%, 5.0 (2.0 - 9.0), t = -0.62, -0.09, 1.32, respectively, all P > 0.05]. After 1 month and 3 months inhaled glucocorticoid therapy, the sputum EOS, ECP, the symptom score, FEV(1) and FEV(1)% pred were [0.019 (0.010 - 0.060), [0.036 (0.006 - 0.070); (173 +/- 153) microg/L, (173 +/- 122) microg/L; 3.0 (1.0 - 6.0), 3.0 (1.0 - 5.0); (2.42 +/- 0.64) L, (2.43 +/- 0.76) L; (77 +/- 13)%, (77 +/- 18)%; respectively in the EOS group, which were significantly different as compared to baseline values (F = 6.73, 6.71, 5.93, 7.38, 5.78, respectively, all P < 0.05). But in the non-EOS group, the sputum EOS, ECP, the symptom score, FEV(1) and FEV(1)% pred were 0.013 (0.000 - 0.025), 0.012 (0.004 - 0.031), (111 +/- 50) microg/L, (117 +/- 50) microg/L; 3.0 (0.0 - 6.0), 3.0 (1.0 - 7.3), (2.22 +/- 0.86) L, (2.21 +/- 0.24) L, (71 +/- 20)%, (65 +/- 21)%; respectively at 1 and 3 months, which showed that the sputum EOS, FEV(1) and FEV(1)% pred did not change (F = 1.98, 0.80, 1.37, respectively, all P > 0.05), but the ECP level and the symptom score improved (F = 3.78, 3.59, respectively, both P < 0.05). Multiple stepwise regression showed that baseline FEV(1), severity degree and sputum EOS correlated significantly with changes in FEV(1) after treatment. Among the baseline indexes examined, sputum EOS had the highest negative predictive value (89.5%) for the response to treatment. CONCLUSIONS: In asthmatics with low sputum EOS, inhaled glucocorticoid therapy for 3 months failed to improve pulmonary function. The result confirmed that low sputum EOS was the best predictor for poor glucocorticoid effect in asthma.

[A study on a therapeutic protocol to improve the control of persistent asthma by monitoring sputum eosinophil counts].

OBJECTIVE: To evaluate the clinical applicability of a therapeutic protocol aiming to improve the control of asthma by reducing the eosinophil (EOS) counts in induced sputum. METHODS: A prospective, randomized and controlled study was conducted from February 2005 to February 2006. Forty-one patients with persistent asthma in the outpatient clinic were enrolled and randomly allocated to management groups either by minimization of the induced sputum EOS (Group A, n = 20) or by standard clinical guidelines (Group B, n = 21). The baseline data were collected after a 2-week run-in period. The doses of inhaled or oral glucocorticoids were adjusted according to sputum EOS count (Group A) or according to symptoms and lung functions (Group B). The patients were followed up for a total of 6 months, during which the patients were assessed for 4 times, at day 15, and at the end of the 2(nd), 4(th) and 6(th) month. Sputum induction and EOS counts were performed at the 2(nd), 3(rd) and 4(th) visits. The primary result was the total number of acute exacerbations. Rescue use of short-acting beta(2)-agonists, symptom scores, lung functions, use of glucocorticoids, and the number of sputum EOS counts were also compared between the groups. RESULTS: In a study period of 6 months, the total numbers of acute exacerbations in Group A and Group B were 11 and 26 respectively, the difference being significant (t = 6.34, P = 0.026). beta(2)-agonist use, symptom score, PEF variability, FEV(1), and the average daily dose of inhaled glucocorticoids were not different between the two groups at any visits. The sputum EOS percentage at baseline and at the end of study in Group A was 0.067 (0.015, 0.169) and 0.048 (0.015, 0.150) respectively, the decrease being significant (F = 3.39, P = 0.02), but in Group B was 0.040 (0.014, 0.133) and 0.045 (0.012, 0.236) respectively (F = 1.07, P = 0.37). CONCLUSION: A treatment strategy directed at reducing the number of the induced sputum EOS count is clinically feasible and effective for the adjustment of glucocorticoids and therefore for a better control of asthma.

[Physiologic response to external positive end-expiratory pressure in mechanically ventilated chronic obstructive pulmonary disease patients].

OBJECTIVE: To evaluate the effects of external positive end-expiratory pressure (PEEPe) on respiratory system mechanics in passively ventilated chronic obstructive pulmonary disease (COPD) patients. METHODS: Fifteen patients with acute exacerbation of COPD were randomly enrolled into the study. The patients were admitted into respiratory intensive care unit (RICU) from Jan, 2005 to Jun, 2006 for controlled mechanical ventilation. PEEPe was applied stepwise from zero to 120% of intrinsic PEEP (PEEPi) in all the 15 patients. At each PEEPe level, airway resistance, compliance (Crs), plateau pressure (Pplat), and total PEEP (PEEPtot) were measured. According to the changes of Pplat after PEEPe application, the patients were divided into 2 sub-groups, abnormal response group (n=11) and a perplexing response group (n=4). RESULTS: In all of the 15 patients, airway resistance at PEEPe equal to 80% and 100% of PEEPi (18.5+/-2.0) cm H2O.L(-1).s(-1) (1 cm H2O=0.098 kPa), (18.0+/-2.2) cm H2O.L(-1).s(-1) were significantly lower than that at zero PEEPe [(23.0+/-2.9) cm H2O.L(-1).s(-1), t=5.36, 6.27 respectively, all P<0.01]. At PEEPe levels equal to 120% of PEEPi, airway resistance (17.3+/-2.1) cm H2O.L(-1).s(-1) and PEEPtot (12.7+/-2.2) cm H2O were significantly different compared with those at zero PEEPe (23.0+/-2.9) cm H2O. L(-1).s(-1), (10.0+/-1.1) cm H2O (t=6.79, -3.90 respectively, all P<0.01). There were no significant differences in baseline PEEPi levels (10.0+/-1.0) cm H2O, (10.0+/-1.4) cm H2O, resistance (22.8+/- 1.9) cm H2O.L(-1).s(-1), (23.1+/-4.1) cm H2O.L(-1).s(-1), Crs (39+/-6) ml/cm H2O, (42+/-9) ml/cm H2O and Pplat (20+/-4) cm H2O, (21+/-3) cm H2O between the normal response and the perplexing response groups (t=0.03, 0.10, 0.60, 0.15 respectively, all P>0.05). However, the corresponding values of Pplat changes at different PEEPe levels in the normal response group [DeltaPplat40 (-0.020+/-0.970) cm H2O, DeltaPplat80 (1.6+/-1.0) cm H2O, DeltaPplat100 (4.0+/-2.9) cm H2O, DeltaPplat120 (6.4+/-3.3) cm H2O] were found to be significantly different compared with those in the perplexing response group [DeltaPplat40 (-7.500+/-0.920) cm H2O, DeltaPplat80 (-4.4+/-1.4) cm H2O, DeltaPplat100 (-3.8+/-1.9) cm H2O, DeltaPplat120 (-1.6+/-1.2) cm H2O] (t=-9.64, -5.90, -3.80, -3.92 respectively, all P<0.01). CONCLUSION: At least in some passively ventilated COPD patients, the applied PEEPe may offer benefit by decreasing the Pplat.

[Relationship between the endocervical mycoplasma infection and spontaneous abortion due to early embryonic death].

OBJECTIVE: To study the relationship between endocervical mycoplasma infection and the spontaneous abortion due to the early embryonic death and the drug sensitivity to mycoplasma. METHODS: Endocervical swabs were taken from fifty normal pregnant women (normal group) and fifty-eight women with spontaneous abortion due to embryonic death. The swabs were used for ureaplasma urealyticum (UU) and mycoplasma hominis (MH) Cultivation respectively. The isolation rates of the two groups were comparedf. RESULTS: (1) In the embryonic death group, the positive rates of UU, MH and UU mixed with MH were 74.1% (43/58), 27.6% (16/58) and 20.7% (12/58) separately. In the normal female group, however, the positive rates correspondingly were the UU 48.0% (24/50), the MH 10.0% (5/50) and the UU mixed with MH 4.0% (2/50). There had significant differences of the positive rates between the two groups (P < 0.01, P < 0.05, P < 0.05). (2) Drug sensitivity rates to mycoplasma were roxithromycin 94.6%, doxycycline 54.5% and ofloxacin 32.8%. (3) The infection rate of mycoplasma had no positive relationship with times of early embryonic death. CONCLUSIONS: (1) The endocervical mycoplasma infection could be one of the causes leading to the early embryonic death. (2) Roxithromycin was the most sensitive drug tested to mycoplasma.