Effect of intra-amniotic fluid pressure from polyhydramnios on cervical length in patients with twin-twin transfusion syndrome undergoing fetoscopic laser surgery.

OBJECTIVES: To determine the relationship between intra-amniotic pressure and cervical length (CL) in patients with twin-twin transfusion syndrome (TTTS) undergoing fetoscopic laser photocoagulation (FLP), and to identify pre- or intraoperative factors associated with increased intra-amniotic pressure in this population. METHODS: This was a prospective cohort study of patients undergoing FLP for TTTS. Exclusion criteria were triplet or higher-order gestation and prior cervical cerclage, amnioreduction or FLP procedure. CL was assessed using preprocedure transvaginal ultrasound. Intra-amniotic pressure measurements were obtained on initial placement of the trocar into the amniotic cavity, using a direct hydrostatic pressure gauge. The relationship between intra-amniotic pressure and CL was assessed using multivariate linear regression analysis, including relevant preoperative and intraoperative variables. RESULTS: In total, 283 pregnancies met the inclusion criteria. Quintero stage of TTTS was I in 33 pregnancies, II in 88, III in 150 and IV in 12. Mean gestational age (GA) at FLP was 20.7 ± 3 weeks. Mean intra-amniotic pressure was 23.1 ± 9 mmHg. On unadjusted linear regression analysis, there was no significant association between intra-amniotic pressure and preoperative CL (P = 0.24) or GA at delivery (P = 0.22). On multivariate analysis, the factors associated significantly with intra-amniotic pressure were: number of prior term deliveries (P = 0.03), recipient maximum vertical pocket (P < 0.0001), Quintero stage IV (P = 0.01) and type of anesthesia (sedation vs general anesthesia; P = 0.01). CONCLUSION: In pregnancies with TTTS, intra-amniotic pressure is not associated with CL or GA at delivery. This novel finding suggests that cervical shortening in this population is not mechanically driven. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Alginate microparticles loaded with lipopolysaccharide subunit antigen for mucosal vaccination against Klebsiella pneumoniae.

Klebsiella pneumoniae (K. pneumoniae) is one of the commonest causes of nosocomial infections in human beings. Since K. pneumoniae infections are air borne type, controlling it by mucosal vaccination through nasal and pulmonary route could be a promising approach in order to simulate the natural infection. New vaccines such as subunit vaccines are safer than traditional vaccines, but they are less immunogenic. Therefore to enhance their immunogenicity, there is a need to develop potent and safe adjuvants and delivery systems. It has been established that micro-particles are one of the most potent adjuvants available for mucosal delivery of vaccines and they do so by improving uptake of encapsulated antigen by antigen presenting cells (APCs). Lipopolysaccharide (LPS), the antigenic fraction was extracted from K. pneumoniae by hot phenol extraction method. LPS loaded sodium alginate microparticles were prepared by emulsion ionic gelation method. Microparticles with particle size less than 5 µm were obtained. Loading efficiency of the LPS loaded microparticles ranged from 76 to 82 %. Comparative in vivo immunogenicity studies were carried for free LPS and encapsulated LPS, administered via intramuscular, intratracheal and intranasal routes in Swiss albino mice. The study revealed that LPS encapsulated microparticles exhibit greater efficacy when administered by intra-tracheal route as compared to free LPS vaccine.