[Serological Characteristics and Clinical Significance of Irregular Antibodies in Pregnant Women]

OBJECTIVE

To understand the serological characteristics of irregular antibodies in pregnant women and explore their clinical significance.

METHODS

From January 2017 to March 2022, 151 471 pregnant women in Women and Children's Hospital of Chongqing Medical University were enrolled in this study, microcolumn gel card test was used for irregular antibody screening, and antibody specificity identification was further performed in some antibody-positive subjects.

RESULTS

The positive rate of irregular antibody screening in the enrolled pregnant women was 0.91% (1 375/151 471), 0.23% (355/151 471) was detected in the first trimester, 0.05% (71/151 471) in the second trimester, and 0.63% (949/151 471) in the third trimester. The positive rate of irregular antibody screening in the third trimester was significantly higher than that in the first and second trimester, and a significant increase in the number of positive cases was found in the third trimester than that in the second trimester. The analysis of agglutination intensity of 1 375 irregular antibody screening positive results showed that the weakly positive agglutination intensity accounted for 50.11% (689/ 1 375), which was the highest, the suspicious positive was 18.69% (257/1 375), and the positive was 31.20% (429/1 375). The significant difference in distribution of agglutination intensity was not observed between the first trimester group and the second trimester group, however, in the third trimester, the proportion of suspicious positive and weakly positive was lower than the first trimester, while, the proportion of positive was higher than the first trimester, and the difference was statistically significant (P < 0.001). Among the irregular antibody screening positive pregnant women, the proportion of pregnant women with pregnancy number ≥ 2 was significantly higher than that with pregnancy ≤ 1. Among 60 pregnant women who underwent antibody identification, the distributions of the antibodies were as follows: Rh blood group system accounted for 23.33% (14/60), Lewis system 43.33% (26/60), Kidd system 3.33% (2/60), MNS system 16.67% (10/60), P1PK system 1.67% (1/60), autoantibodies 1.67% (1/60), and 4 cases was unable to identify (6.67%, 4/60). Among specific antibodies, the anti-Lea was the most common (30.00%), followed by anti-E (16.67%) and anti-M (16.67%).

CONCLUSION

The differences of irregular antibody serological characteristics exist in pregnant women from different regions with different genetic backgrounds, understanding the characteristics of irregular antibody in local pregnant women is of great significance for ensuring transfusion safety in pregnant women and preventing hemolytic disease of newborn.

Features of MR signals of retroplacental basal decidual space and its diagnostic significance

BACKGROUND

With more pregnant women undergoing cesarean section, the number of women with scarring in the uterus undergoing uterine magnetic resonance (MR) examination in the second and third trimesters following a subsequent pregnancy, has increased.

OBJECTIVE

To investigate features of MR signals in retroplacental basal decidual space.

METHODS

The MR imaging data of patients with clinically and pathologically confirmed placenta implantation and complete placental abruption were retrospectively analyzed.

RESULTS

Patients with high-intensity signals in T2-weighted images (T2WI) of the retroplacental basal decidual space did not suffer placenta implantation after delivery, while high-intensity signals in T2WI of the retroplacental basal decidual space was not observed in patients with different degrees of placenta implantation.

CONCLUSION

As the retroplacental basal decidual space is the barrier between the placenta and myometrium, high-intensity signals in T2WI can improve the confidence of MR exclusion diagnostics of placenta implantation, and can be used as exclusion criteria for MR diagnosis of placenta implantation.

A Quantitative Study of the Dimensional Change of Inferior Vena Cava on Computed Tomography During Acute Hemorrhage Shock in Swine

Background: The purpose of this study was to examine the dimensional change of IVC during acute hemorrhage through a volume-controlled acute hemorrhagic shock model in swine. Methods: Volume-controlled hemorrhage was performed in 10 adult Bama mini pigs. Enhanced CT scan and hemodynamic monitoring were performed when the cumulative blood loss volume reached 0%, 10%, 20%, 30%, and 40%. The transverse diameter (T) and anteroposterior diameter (AP) of IVC were measured in axial images. Hemodynamic parameters were obtained with Pulse Contour Cardiac Output (PiCCO) hemodynamic monitor device. Arterial blood samples were also collected for artery blood gas analysis at each time point. Results: As the blood loss volume increased, the collapsibility (T/AP) and cross section area (CSA) of IVC significantly changed first in hepatic level and pre-renal level. The significant decrease of the CSA of IVC (shrink) occurred early when the blood loss volume reached only 10%, but the collapse of IVC occurred until the blood loss volume reached 30%. Conclusions: IVC shrank early but collapsed late during the acute hemorrhage in swine. The finding of collapsed IVC on CT scans suggested severe hypovolemic shock. Evaluation of the IVC at the CT scans can be an adjunctive test of the hemodynamic status in trauma patients.

Effect of retension sutures on abdominal pressure after abdominal surgery

PURPOSE

To evaluate the effect of retention sutures on abdominal pressure and postoperative prognosis in abdominal surgery patients.

METHODS

This prospective cohort study included patients who were admitted to Daping Hospital from May 15, 2014 to October 11, 2014. A total of 57 patients were enrolled, including 18 patients in the "U" type retention suture group, 17 patients in the intermittent retention suture group, and 22 patients in non-retention suture group. The demographic data, clinical data and risk factors for abdominal wound dehiscence were recorded. The bladder pressure (IVP) was monitored preoperatively, intraoperatively, and four days postoperatively. Additionally, the incidence of abdominal wound dehiscence and infection 14 days after the operation was recorded.

RESULTS

During the operation, the IVP decreased and then increased; it was at its lowest 1 h after the start of the operation (5.3 mmHg ± 3.2 mmHg) and peaked after tension-reducing (8.8 mmHg ± 4.0 mmHg). The IVP values in the "U" type retention suture group and intermittent retention suture group were higher than in the non-retention suture group 4 days after operation (p < 0.005). The Visual Analogue Scale (VAS) pain scores were 3.9 ± 2.2, 3.8 ± 2.0, and 3.0 ± 1.0 in the retention suture group, intermittent retention suture group and non-retention suture group, respectively. The VAS pain scores in the "U" type tension-reducing group and intermittent tension-reducing group were higher than in the non-tension-reducing group (p < 0.005).

CONCLUSION

Although retention sutures may reduce the incidence of postoperative wound dehiscence in abdominal surgery patients, they can increase the IVP and postoperative pain.

Graphene Q-switched distributed feedback fiber lasers with narrow linewidth approaching the transform limit

A compact all-in-line graphene-based distributed feedback Bragg-grating fiber laser (GDFB-FL) with narrow linewidth of hundreds kHz is demonstrated and investigated in this study. Performing as an optical saturable absorber, graphene oscillates the initially kHz linewidth DFB-FL, and generates high-quality passively Q-switched pulses. Pumped with a 980 nm continuous-wave laser, the Q-switched GDFB-FL observes ~1 μs pulse durations, with pulse energies up to ~10 nJ and approaching the transform limit. The peak power is ~600 times higher than the original DFB-FL laser. By optimizing the cavity design and the graphene material, it is predicted that fast Q-switched pulses with more than MHz repetition rates and sub-100 ns pulse durations are achievable. Such transform-limited Q-switched GDFB-FLs with narrow linewidth of sub-MHz have long coherence length, good tunability, stability, compactness and robustness, with potential impact in optical coherent communications, metrology and sensing.

[Effect of insulin-like growth factor-1 on hyperoxia-induced apoptosis in A549 cells]

OBJECTIVE

To investigate the effect of insulin-like growth factor-1 (IGF-1), which can promote cell differentiation and inhibit cell apoptosis, on hyperoxia-induced apoptosis in A549 cells and its anti-apoptotic mechanism.

METHODS

A549 cells were sub-cultured, exposed to hyperoxic conditions and were then treated with different concentrations of IGF-1 (1, 10, and 100 ng/mL) for 48 hours. Cell viability was measured by MTT assay. Cell apoptosis was evaluated by Annexin V-FITC/PI double-staining flow cytometry. Expression levels of Bax and Bcl-2 were measured by flow cytometry.

RESULTS

The middle-dose and high-dose IGF-1 intervention groups had higher cell viabilities than the hyperoxic exposure group [(64±3)% and (88±4)% vs (51±3)%; P<0.05]. Compared with the air control group, the hyperoxic exposure group had a significantly higher apoptotic rate [(38.3±5.4)% vs (2.4±0.9)%; P<0.05], a significantly lower expression level of Bcl-2 [(72±5)% vs (91±4)%; P<0.05], and a significantly higher expression level of Bax [(54±6)% vs (3±2)%; P<0.05]. Compared with the hyperoxic exposure group, the low-dose, middle-dose, and high-dose IGF-1 intervention groups had significantly lower apoptotic rates [(16.1±4.7)%, (9.2±2.8)%, and (6.9±2.5)% vs (38.3±5.4)%; P<0.05], significantly higher expression level of Bcl-2 [(79±4)%, (94±4)%, and (100±5)% vs (72±5)%; P<0.05], and significantly lower expression level of Bax [(26±4)%, （5±2)%, and (4±2)% vs (54±6)%; P<0.05].

CONCLUSIONS

Hyperoxia significantly inhibits proliferation and promotes apoptosis in A549 cells. IGF-1 may promote cell proliferation and inhibit hyperoxia-induced apoptosis in A549 cells by regulating the expression of Bcl-2 and Bax.