Feasibility of Direct Vitrectomy-Sparing Subretinal Injection for Gene Delivery in Large Animals.

PURPOSE: To assess the safety and feasibility of direct vitrectomy-sparing subretinal injection for gene delivery in a large animal model. METHODS: The experimental Libechov minipigs were used for subretinal delivery of a plasmid DNA vector (pS/MAR-CMV-copGFP) with cytomegalovirus (CMV) promoter, green fluorescent protein (GFP) reporter (copGFP) and a scaffold/matrix attachment region (S/MAR) sequence. The eyes were randomized to subretinal injection of the vector following pars plana vitrectomy (control group) or a direct injection without prior vitrectomy surgery (experimental group). Intra- and post-operative observations up to 30 days after surgery were compared. RESULTS: Six eyes of three mini-pigs underwent surgery for delivery into the subretinal space. Two eyes in the control group were operated with a classical approach (lens-sparing vitrectomy and posterior hyaloid detachment). The other four eyes in the experimental group were injected directly with a subretinal cannula without vitrectomy surgery. No adverse events, such as endophthalmitis, retinal detachment and intraocular pressure elevation were observed post-operatively. The eyes in the experimental group had both shorter surgical time and recovery while achieving the same surgical goal. CONCLUSIONS: This pilot study demonstrates that successful subretinal delivery of gene therapy vectors is achievable using a direct injection without prior vitrectomy surgery.

High protein intake can lead to serious hypophosphatemia and hypokalemia in growth restricted preterm newborns.

Objectives: High protein parenteral nutrition (HPPN) in the early postnatal period is a recommended strategy for very low birth weight (VLBW) infants. However, limited data is available on electrolyte changes when HPPN strategy is utilized. We investigated the impact of HPPN on the development of hypophosphatemia and hypokalemia in preterm VLBW newborns. Methods: A retrospective, single-center study investigated the levels of phosphate and potassium in VLBW infants who received HPPN (amino acids intake up to 3.5 g/kg/day) during the first week of life. Preterm infants were divided into two subgroups: appropriate for gestational age (AGA) and small for gestational age (SGA) newborns. Clinical data were obtained from hospital database and medical records. Results: Overall, 170 VLBW infants were included for the study analysis: 41 SGA (mean birth weight 752 ± 39 g) and 129 AGA infants (mean birth weight 994 ± 23 g). Phosphate and potassium levels were significantly lower in the SGA infants compared to AGA infants (Phosphate: 0.97 ± 0.07 mmol/l vs. 1.44 ± 0.04 mmol/l, p < 0.001; Potassium: 3.0 ± 0.1 mmol/l vs. 3.6 ± 0.1 mmol/l, p < 0.001). Conclusions: Repeated measurement of serum phosphate and potassium is recommended when HPPN strategy is utilized in preterm SGA infants where significant hypophosphatemia and hypokalemia might have serious clinical consequences.

Does perinatal management have the potential to reduce the risk of intraventricular hemorrhage in preterm infants?

Background: Intraventricular hemorrhage (IVH) is an important cause of neurodevelopmental impairment in preterm infants. A number of risk factors for IVH have already been proposed; however, some controversies regarding optimal perinatal management persist. This study aimed to identify perinatal and neonatal attributes associated with IVH in a representative population of preterm infants. Methods: Perinatal data on 1,279 very preterm infants (<32 weeks of gestation) admitted to a tertiary neonatal intensive care unit were analyzed. The records were assessed using univariate analysis and logistic regression model to evaluate the risk factors for any and high-grade IVH (grade III-IV according to the classification by Papile) within the first week after birth. Results: The incidence of any IVH was 14.3% (183/1,279); the rate of low-grade (I-II) and high-grade (III-IV) IVH was 9.0% (115/1,279) and 5.3% (68/1,279), respectively. Univariate analysis revealed multiple factors significantly associated with intraventricular hemorrhage: lower gestational age and birth weight, absence of antenatal steroids, vaginal delivery, low Apgar score at 5 min, delivery room intubation, surfactant administration, high frequency oscillation, pulmonary hypertension, pulmonary hemorrhage, tension pneumothorax, persistent ductus arteriosus, hypotension and early onset sepsis. Logistic regression confirmed lower gestational age, vaginal delivery, ductus arteriosus and early onset sepsis to be independent predictors for any IVH. Pulmonary hemorrhage, tension pneumothorax and early onset sepsis were independent risk factors for high-grade IVH. Complete course of antenatal steroids was associated with a lower risk for any (odds ratio 0.58, 95% confidence interval 0.39-0.85; P = .006) and for high-grade intraventricular hemorrhage (odds ratio 0.36, 95% confidence interval 0.20-0.65; P < .001). Conclusion: The use of antenatal steroids and mode of delivery are crucial in the prevention of IVH; however, our study did not confirm the protective effect of placental transfusion. Severe respiratory insufficiency and circulatory instability remain to be powerful contributors to the development of IVH. Early detection and management of perinatal infection may also help to reduce the rate of brain injury and improve neurodevelopment in high-risk newborns.

Macular pigment evaluation using dual-wavelength fundus auto-fluorescence imaging.

INTRODUCTION: Macular pigment plays an important role in the reduction of oxidative stress and in preventing retinal diseases. Quick and easy measurements of the macular pigment are essential in both clinical and research settings. Dual wavelength fundus auto-fluorescence seems to be the optimal method. This study aims to investigate changes in fundus autofluorescence in patients taking daily lutein oral supplements and develop image processing methods for follow-up evaluations of the images. METHODS: New devices allow us to examine fundus autofluorescence using both blue and green excitation wavelengths. This allows detection of the amount of macular pigment by subtracting these two images because the yellow pigment particles absorb blue wavelengths. We determined daily dose of 25 mg of lutein and 3 mg of zeaxanthin. Patients were followed up for 15 months at 3-month intervals. RESULTS: During our 15-month study, we observed a positive trend in pixel lightness values, suggesting an increase in macular pigments in the foveal area. In all patients taking daily lutein supplements, the foveal index significantly increased after six months, with a median change of 0.081. We did not observe a significant change after the first three months (0.006) and only a small change between the 6th and 12th-month visits (0.012). CONCLUSION: With appropriate patients and procedures for capturing autofluorescence images, this is a valuable technique for macular pigment evaluation in follow-up examinations using software image post-processing and analysis with commonly available hardware. To put this into everyday practice, developing tools to automate the assessment is necessary.

Abnormal kidney ultrasound and function in a five-year-old boy born prematurely with a birth weight of 370 grams.

It is known that prematurity and low birth weight are associated with chronic kidney disease and hypertension. A positive correlation between kidney volume and birth weight was also described. In our ongoing observational study in 5-year-old children, we perceived highly abnormal kidney ultrasound and functions of a male patient born weighing 370 grams. It was his first nephrology examination since discharge from the hospital. We believe that thorough follow up and timely diagnosis of developing renal insufficiency may help us to initiate proper treatment in high-risk children (Tab. 1, Fig. 1, Ref. 7). Text in PDF www.elis.sk Keywords: prematurity; extremely low birth weight; chronic kidney disease; renal ultrasound; renal function.

Macular hole Delphi consensus statement (MHOST).

PURPOSE: To derive a Delphi method-based consensus for the surgical management of Full Thickness Macular Hole (FTMH) and Lamellar Macular Hole (LMH). METHODS: 37 expert VR surgeons from 21 mainly European countries participated in Delphi method-based questionnaire for diagnosis and treatment of FTMHs and LMHs. RESULTS: A total of 36 items were rated in round 1 by 37 participants, of which 10 items achieved consensus: intraoperative verification of PVD; clinical superiority of OCT-based FTMH classification; practical ineffectiveness of ocriplasmin; circular 360° ILM peeling for small macular holes; use of regular surgical technique for the size of the hole in concomitant retinal detachment; performing complete vitrectomy; SF6 gas as preferred tamponade; cataract surgery if crystalline lens is mildly/moderately opaque; removal of both ILM and LHEP in LMH surgery. In round 2, 18 items with moderate consensus (45-70% agreement) in round 1 were rated by 35 participants. Final consensus was reached in 35% of questions related to both diagnosis and surgical procedures. CONCLUSIONS: This Delphi study provides valuable information about the consensus/disagreement on different scenarios encountered during FTMH and LMH management as a guide tosurgical decision-making. High rate of disagreement and/or variable approaches still exist for treating such relatively common conditions.

Machine Learning Detects Intraventricular Haemorrhage in Extremely Preterm Infants.

OBJECTIVE: To test the potential utility of applying machine learning methods to regional cerebral (rcSO2) and peripheral oxygen saturation (SpO2) signals to detect brain injury in extremely preterm infants. STUDY DESIGN: A subset of infants enrolled in the Management of Hypotension in Preterm infants (HIP) trial were analysed (n = 46). All eligible infants were <28 weeks' gestational age and had continuous rcSO2 measurements performed over the first 72 h and cranial ultrasounds performed during the first week after birth. SpO2 data were available for 32 infants. The rcSO2 and SpO2 signals were preprocessed, and prolonged relative desaturations (PRDs; data-driven desaturation in the 2-to-15-min range) were extracted. Numerous quantitative features were extracted from the biosignals before and after the exclusion of the PRDs within the signals. PRDs were also evaluated as a stand-alone feature. A machine learning model was used to detect brain injury (intraventricular haemorrhage-IVH grade II-IV) using a leave-one-out cross-validation approach. RESULTS: The area under the receiver operating characteristic curve (AUC) for the PRD rcSO2 was 0.846 (95% CI: 0.720-0.948), outperforming the rcSO2 threshold approach (AUC 0.593 95% CI 0.399-0.775). Neither the clinical model nor any of the SpO2 models were significantly associated with brain injury. CONCLUSION: There was a significant association between the data-driven definition of PRDs in rcSO2 and brain injury. Automated analysis of PRDs of the cerebral NIRS signal in extremely preterm infants may aid in better prediction of IVH compared with a threshold-based approach. Further investigation of the definition of the extracted PRDs and an understanding of the physiology underlying these events are required.

Complications of planned home births in the Czech Republic.

OBJECTIVES: This study evaluated complications that can occur during planned home births that require transfer to the hospital. These factors were assessed to improve the current status of deliveries performed outside health care facilities in the Czech Republic. MATERIALS AND METHODS: This prospective cohort study included data on 105 cases of complicated home births during 2017 to 2021 using an online form accessible to all hospital maternity wards in the Czech Republic. RESULTS: Planned home births were complicated by fetal/neonatal causes, maternal causes, and combined fetomaternal complications in 28 (26.7%), 20 (19%), and 2 (1.9%) cases, respectively. The need for transfer was most often realized after the birth of the fetus (86; 81.9%); however, it was realized during birth in 19 (18.1%) cases. The following complications were noted most often: postpartum hemorrhage (23; 21.9%); neonatal asphyxia (17; 16.2); placental retention (14; 13.3%); birth injury (12; 11.4%); neonatal hypothermia (5; 4.8%); and placental birth (5; 4.8%). Indications for transfer during labor were as follows: labor obstruction (10; 9.5%); fetal hypoxia (5; 4.8%); bleeding during labor (2; 1.9%); preeclampsia (1; 0.9%); and fetal malformation (1; 0.9%). Perinatal death occurred in 8 (7.6%) cases. Permanent neonatal morbidity occurred in 4 (3.8%) cases. CONCLUSIONS: Patients with home birth complications were transferred to the hospital most often after the birth of the fetus. The low proportion of transfers during childbirth is caused by the unprofessional management of planned home births, resulting in a high number of perinatal deaths and high rate of permanent neonatal morbidity.

Release of HMGB1 and Toll-like Receptors 2, 4, and 9 Signaling Are Modulated by Bifidobacterium animalis subsp. lactis BB-12 and Salmonella Typhimurium in a Gnotobiotic Piglet Model of Preterm Infants.

Gnotobiotic (GN) animals with defined microbiota allow us to study host-microbiota and microbiota-microbiota interferences. Preterm germ-free (GF) piglets were mono-associated with probiotic Bifidobacterium animalis subsp. lactis BB-12 (BB12) to ameliorate/prevent the consequences of infection with the Salmonella Typhimurium strain LT2 (LT2). Goblet cell density; expression of Toll-like receptors (TLRs) 2, 4, and 9; high mobility group box 1 (HMGB1); interleukin (IL)-6; and IL-12/23p40 were analyzed to evaluate the possible modulatory effect of BB12. BB12 prevented an LT2-induced decrease of goblet cell density in the colon. TLRs signaling modified by LT2 was not influenced by the previous association with BB12. The expression of HMGB1, IL-6, and IL12/23p40 in the jejunum, ileum, and colon and their levels in plasma were all decreased by BB12, but these changes were not statistically significant. In the colon, differences in HMGB1 distribution between the GF and LT2 piglet groups were observed. In conclusion, the mono-association of GF piglets with BB12 prior to LT2 infection partially ameliorated the inflammatory response to LT2 infection.

Serial Measurement of Interleukin-6 Enhances Chance to Exclude Early-Onset Sepsis in Very Preterm Infants.

The aim of this retrospective study was to evaluate the reliability of peak interleukin-6 (IL-6) level within 24 hours after delivery as a predictor for early-onset sepsis (EOS) in very preterm neonates. Interleukin-6 was assessed at 2 hours and at 12 to 24 hours after delivery. The highest level was considered a peak value. The definition of EOS was based on positive blood culture and clinical signs of infection or negative blood culture, clinical signs of infection, and C-reactive protein >10 mg/L. Among 445 enrolled infants, 53 developed EOS. A peak IL-6 level of more than 200 ng/L had a sensitivity of 89% and specificity of 77% for the presence of EOS. The negative predictive value was 98%. Receiver operating characteristics curve had area under the curve of 0.92. Peak IL-6 is a reliable marker of systemic inflammatory response and might be useful to exclude EOS within the first 24 hours.

Subretinal Implantation of RPE on a Carrier in Minipigs: Guidelines for Preoperative Preparations, Surgical Techniques, and Postoperative Care.

Degenerative disorders of the retina (including age-related macular degeneration), which originate primarily at or within the retinal pigmented epithelial (RPE) layer, lead to a progressive disorganization of the retinal anatomy and the deterioration of visual function. The substitution of damaged RPE cells (RPEs) with in vitro cultured RPE cells using a subretinal cell carrier has shown potential for re-establishing the anatomical structure of the outer retinal layers and is, therefore, being further studied. Here, we present the principles of a surgical technique that allows for the effective subretinal transplantation of a cell carrier with cultivated RPEs into minipigs. The surgeries were performed under general anesthesia and included a standard lens-sparing three-port pars plana vitrectomy (PPV), subretinal application of a balanced salt solution (BSS), a 2.7 mm retinotomy, implantation of a nanofibrous cell carrier into the subretinal space through an additional 3.0 mm sclerotomy, fluid-air exchange (FAX), silicone oil tamponade, and closure of all the sclerotomies. This surgical approach was used in 29 surgeries (18 animals) over the past 8 years with a success rate of 93.1%. Anatomic verification of the surgical placement was carried out using in vivo fundus imaging (fundus photography and optical coherence tomography). The recommended surgical steps for the subretinal implantation of RPEs on a carrier in minipig eyes can be used in future preclinical studies using large-eye animal models.

Neonatal Sequential Organ Failure Assessment (nSOFA) Score within 72 Hours after Birth Reliably Predicts Mortality and Serious Morbidity in Very Preterm Infants.

The aim of this study was to assess the applicability of the neonatal sequential organ failure assessment score (nSOFA) within 72 h after delivery as a predictor for mortality and adverse outcome in very preterm neonates. Inborn neonates <32 weeks of gestation were evaluated. The nSOFA scores were calculated from medical records in the first 72 h after birth and the peak value was used for analysis. Death or composite morbidity at hospital discharge defined the adverse outcome. Composite morbidity consisted of chronic lung disease, intraventricular haemorrhage ≥grade III, periventricular leukomalacia and necrotizing enterocolitis. Among 423 enrolled infants (median birth weight 1070 g, median gestational age 29 weeks), 27 died and 91 developed composite morbidity. Death or composite morbidity was associated with organ dysfunction as assessed by nSOFA, systemic inflammatory response, and low birthweight. The score >2 was associated with OR 2.5 (CI 1.39−4.64, p = 0.002) for the adverse outcome. Area under the curve of ROC was 0.795 (95% CI = 0.763−0.827). The use of nSOFA seems to be reasonable for predicting mortality and morbidity in very preterm infants. It constitutes a suitable basis to measure the severity of organ dysfunction regardless of the cause.

Trends in Neonatal Ophthalmic Screening Methods.

Neonatal ophthalmic screening should lead to early diagnosis of ocular abnormalities to reduce long-term visual impairment in selected diseases. If a treatable pathology is diagnosed within a few days after the birth, adequate therapy may be indicated to facilitate the best possible conditions for further development of visual functions. Traditional neonatal ophthalmic screening uses the red reflex test (RRT). It tests the transmittance of the light through optical media towards the retina and the general disposition of the central part of the retina. However, RRT has weaknesses, especially in posterior segment affections. Wide-field digital imaging techniques have shown promising results in detecting anterior and posterior segment pathologies. Particular attention should be paid to telemedicine and artificial intelligence. These methods can improve the specificity and sensitivity of neonatal eye screening. Both are already highly advanced in diagnosing and monitoring of retinopathy of prematurity.

Triacylglycerols containing branched palmitic acid ester of hydroxystearic acid (PAHSA) are present in the breast milk and hydrolyzed by carboxyl ester lipase.

Breast milk is a complex mixture containing underexplored bioactive lipids. We performed an observational case-control study to compare the impact of delivery mode: caesarean section (CS) and vaginal birth (VB); and term (preterm and term delivery) on the levels of lipokines in human milk at different stages of lactation. Metabolomic analysis of the milk identified triacylglycerol estolides as a metabolic reservoir of the anti-inflammatory lipid mediator 5-palmitic acid ester of hydroxystearic acid (5-PAHSA). We found that triacylglycerol estolides were substrates of carboxyl ester lipase and 5-PAHSA-containing lipids were the least preferred substrates among tested triacylglycerol estolide isomers. This explained exceptionally high colostrum levels of 5-PAHSA in the VB group. CS and preterm birth negatively affected colostrum lipidome, including 5-PAHSA levels, but the lipidomic profiles normalized in mature milk. Mothers delivering term babies vaginally produce colostrum rich in 5-PAHSA, which could contribute to the prevention of intestinal inflammation in newborns.

Subretinal Implantation of Human Primary RPE Cells Cultured on Nanofibrous Membranes in Minipigs.

PURPOSE: The development of primary human retinal pigmented epithelium (hRPE) for clinical transplantation purposes on biodegradable scaffolds is indispensable. We hereby report the results of the subretinal implantation of hRPE cells on nanofibrous membranes in minipigs. METHODS: The hRPEs were collected from human cadaver donor eyes and cultivated on ultrathin nanofibrous carriers prepared via the electrospinning of poly(L-lactide-co-DL-lactide) (PDLLA). "Libechov" minipigs (12-36 months old) were used in the study, supported by preoperative tacrolimus immunosuppressive therapy. The subretinal implantation of the hRPE-nanofibrous carrier was conducted using general anesthesia via a custom-made injector during standard three-port 23-gauge vitrectomy, followed by silicone oil endotamponade. The observational period lasted 1, 2, 6 and 8 weeks, and included in vivo optical coherence tomography (OCT) of the retina, as well as post mortem immunohistochemistry using the following antibodies: HNAA and STEM121 (human cell markers); Bestrophin and CRALBP (hRPE cell markers); peanut agglutining (PNA) (cone photoreceptor marker); PKCα (rod bipolar marker); Vimentin, GFAP (macroglial markers); and Iba1 (microglial marker). RESULTS: The hRPEs assumed cobblestone morphology, persistent pigmentation and measurable trans-epithelial electrical resistance on the nanofibrous PDLLA carrier. The surgical delivery of the implants in the subretinal space of the immunosuppressed minipigs was successfully achieved and monitored by fundus imaging and OCT. The implanted hRPEs were positive for HNAA and STEM121 and were located between the minipig's neuroretina and RPE layers at week 2 post-implantation, which was gradually attenuated until week 8. The neuroretina over the implants showed rosette or hypertrophic reaction at week 6. The implanted cells expressed the typical RPE marker bestrophin throughout the whole observation period, and a gradual diminishing of the CRALBP expression in the area of implantation at week 8 post-implantation was observed. The transplanted hRPEs appeared not to form a confluent layer and were less capable of keeping the inner and outer retinal segments intact. The cone photoreceptors adjacent to the implant scaffold were unchanged initially, but underwent a gradual change in structure after hRPE implantation; the retina above and below the implant appeared relatively healthy. The glial reaction of the transplanted and host retina showed Vimentin and GFAP positivity from week 1 onward. Microglial activation appeared in the retinal area of the transplant early after the surgery, which seemed to move into the transplant area over time. CONCLUSIONS: The differentiated hRPEs can serve as an alternative cell source for RPE replacement in animal studies. These cells can be cultivated on nanofibrous PDLLA and implanted subretinally into minipigs using standard 23-gauge vitrectomy and implantation injector. The hRPE-laden scaffolds demonstrated relatively good incorporation into the host retina over an eight-week observation period, with some indication of a gliotic scar formation, and a likely neuroinflammatory response in the transplanted area despite the use of immunosuppression.

A Randomized, Controlled Trial to Investigate the Efficacy of Nebulized Poractant Alfa in Premature Babies with Respiratory Distress Syndrome.

OBJECTIVE: To investigate the efficacy and safety of nebulized poractant alfa (at 200 and 400 mg/kg doses) delivered in combination with nasal continuous positive airway pressure compared with nasal continuous positive airway pressure alone in premature infants with diagnosed respiratory distress syndrome. STUDY DESIGN: This randomized, controlled, multinational study was conducted in infants at 280/7 to 326/7 weeks of gestation. The primary outcome was the incidence of respiratory failure in the first 72 hours of life, defined as needing endotracheal surfactant and/or mechanical ventilation owing to prespecified criteria. Secondary outcomes included the time to respiratory failure in the first 72 hours, duration of ventilation, mortality, incidence of bronchopulmonary dysplasia, and major associated neonatal comorbidities. In addition, the safety and tolerability of the treatments were assessed reporting the number and percentage of infants with treatment-emergent adverse events and adverse drug reactions during nebulization. RESULTS: In total, 129 infants were randomized. No significant differences were observed for the primary outcome: 24 (57%), 20 (49%), and 25 (58%) infants received endotracheal surfactant and/or mechanical ventilation within 72 hours in the poractant alfa 200 mg/kg, poractant alfa 400 mg/kg, and nasal continuous positive airway pressure groups, respectively. Similarly, secondary respiratory outcomes did not differ among groups. Enrollment was halted early owing to a change in the benefit-risk balance of the intervention. Nebulized poractant alfa was well-tolerated and safe, and no serious adverse events were related to the study treatment. CONCLUSIONS: The intervention did not decrease the likelihood of respiratory failure within the first 72 hours of life. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03235986.

Bacterial DNA detection in very preterm infants assessed for risk of early onset sepsis.

OBJECTIVES: The aim of this study is to evaluate the diagnostic ability of multiplex real-time polymerase chain reaction (PCR) in very preterm infants assessed for risk of early onset neonatal sepsis (EOS). METHODS: Prospective observational cohort study. Blood samples of preterm neonates ≤32 weeks of gestation were evaluated by commercial multiplex real-time PCR within 2 h after delivery. The definition of EOS was based on positive blood culture and clinical signs of infection or negative blood culture, clinical signs of infection and abnormal neonatal blood count and serum biomarkers. RESULTS: Among 82 subjects analyzed in the study, 15 had clinical or confirmed EOS. PCR was positive in four of these infants (including the only one with a positive blood culture), as well as in 15 of the 67 infants without sepsis (sensitivity 27%, specificity 78%). Out of 19 PCR positive subjects, Escherichia coli was detected in 12 infants (63%). Statistically significant association was found between vaginal E. coli colonization of the mother and E. coli PCR positivity of the neonate (p=0.001). No relationship was found between neonatal E. coli swab results and assessment findings of bacterial DNA in neonatal blood stream. CONCLUSIONS: Multiplex real-time PCR had insufficient diagnostic capability for EOS in high risk very preterm infants. The study revealed no significant association between PCR results and the diagnosis of clinical EOS. Correlation between maternal vaginal swab results and positive PCR in the newborn needs further investigation to fully understand the role of bacterial DNA analysis in preterm infants.

Advantages of nanofibrous membranes for culturing of primary RPE cells compared to commercial scaffolds.

PURPOSE: Dysfunction of the retinal pigment epithelium (RPE) causes numerous forms of retinal degeneration. RPE replacement is a modern option to save vision. We aimed to test the results of transplanting cultured RPEs on biocompatible membranes. METHODS: We cultivated porcine primary RPE cells isolated from cadaver eyes from the slaughterhouse on two types of membranes: commercial polyester scaffolds Transwell (Corning Inc., Kenneburg, ME, USA) with 0.4 µm pore size and prepared Poly (L-lactide-co-DL-lactide) (PDLLA) nanofibrous membranes with an average pore size of 0.4 µm. RESULTS: Five types of assays were used for the analysis: immunocytochemistry (ICC), phagocytosis assay, Western blotting, real-time qPCR (RT-qPCR) and electron microscopy. RT-qPCR demonstrated that RPEs cultured on nanofibrous membranes have higher expressions of BEST1 (bestrophin 1), RLBP1 (retinaldehyde-binding protein 1), RPE65 (retinal pigment epithelium-specific 65 kDa protein), PAX6 (transcription factor PAX6), SOX9 (transcription factor SOX9), DCT (dopachrome tautomerase) and MITF (microphthalmia-associated transcription factor). ICC of the RPEs cultured on nanofibrous membranes showed more intensive staining of markers such as BEST1, MCT1 (monocarboxylate transporter 1), Na+ /K+ ATPase, RPE65 and acetylated tubulin in comparison with commercial ones. Additionally, the absence of α-SMA proved the stability of the RPE polarization state and the absence of epithelial-to-mesenchymal transition. RPE possessed high phagocytic activity. Electron microscopy of both membranes confirmed a confluent layer of RPE cells and their genuine morphological structure, which was comparable to native RPEs. CONCLUSIONS: Retinal pigment epitheliums cultured on polylactide nanofibrous membranes improved the final quality of the cell product by having better maturation and long-term survival of the RPE monolayer compared to those cultured on commercial polyester scaffolds. PDLLA-cultured RPEs are a plausible source for the replacement of non-functioning RPEs during cell therapy.

A first-in-human clinical study of a new SP-B and SP-C enriched synthetic surfactant (CHF5633) in preterm babies with respiratory distress syndrome: two-year outcomes.

OBJECTIVE: To assess at 24 months corrected age (CA) the neurological, respiratory, and general health status of children born prematurely from 27+0 to 33+6 weeks' gestation who were treated in a first-in-human study with a new fully synthetic surfactant (CHF5633) enriched with SP-B and SP-C proteins. OUTCOME MEASURES: Children were assessed using Bayley Scales of Infant Development (BSID), with a score below normal defined as BSID-II Mental Development Index score <70, or BSID-III cognitive composite score <85. In addition, a health status questionnaire was used to check for functional disability including respiratory problems and related treatments, sensory and neurodevelopment assessments, communication skills as well as the number of hospitalizations. RESULTS: 35 of 39 survivors had a neurodevelopmental assessment, 24 infants being evaluated by Bayley's Scales and 11 by health status questionnaires only. 23 children had scores within normal limits and one had BSID-III <85. The remaining 11 were judged clinically to have normal development. Health status questionnaires detected only issues that would normally be expected in preterm-born children. CONCLUSIONS: This assessment offers reassurance that treatment with CHF5633 surfactant was not associated with adverse neurodevelopmental, respiratory, or health outcomes by two years corrected age.

Large Platelet and Endothelial Extracellular Vesicles in Cord Blood of Preterm Newborns: Correlation with the Presence of Hemolysis.

Different biomarkers are investigated to detect the causes of severe complications in preterm infants. Extracellular vesicles (EVs) are recognized as an important part of cell-to-cell communication, and their increased levels were reported in numerous pathological states. We aimed to increase our knowledge about the incidence of platelet and endothelial EVs in cord blood of preterm newborns using conventional flow cytometry. The presence of platelet (CD36+CD41+), activated platelet (CD41+CD62+), and endothelial (CD31+CD105+) EVs was analyzed. Immune electron microscopy was used to confirm the presence of EVs and the specificity of their labeling. The size of detected extracellular vesicles was in the range 400-2000 nm. The differences in the counts of EVs between the preterm and control group were not significant and no correlation of EVs count with gestation age was recorded. Cord blood plasma samples with free hemoglobin level > 1 mg/mL had more than threefold higher counts of CD36+CD41+ and CD41+CD62+ EVs (p < 0.001), while the count of CD31+CD105+ EVs was only moderately increased (p < 0.05). Further studies utilizing cytometers with improved sensitivity are needed to confirm that the analysis of large platelet and endothelial EVs mirrors the quantitative situation of their whole plasma assemblage.