Calf pulmonary surfactant

Microplastics (MPs) are ubiquitous environmental pollutants produced through the degradation of plastic products. Nanoplastics (NPs), commonly coexisting with MPs in the environment, are submicrometer debris incidentally produced from fragmentation of MPs. We studied the biophysical impacts of MPs/NPs derived from commonly used commercial plastic products on a natural pulmonary surfactant extracted from calf lung lavage. It was found that in comparison to MPs/NPs derived from lunch boxes made of polypropylene or from drinking water bottles made of poly(ethylene terephthalate), the MP/NP derived from foam packaging boxes made of polystyrene showed the highest adverse impact on the biophysical function of the pulmonary surfactant...

Conventional liposomes often lack stability, limiting their applicability and usage apart from intravenous routes. Nevertheless, their advantages in drug encapsulation and physicochemical properties might be helpful in oral and pulmonary drug delivery. This study investigated the feasibility and stability of liposomes containing tetraether lipids (TEL) from Thermoplasma acidophilum . Liposomes composed of different molar ratios of TEL:Phospholipon 100H (Ph) were produced and exposed to various temperature and pH conditions...

BACKGROUND: Approaches to the evaluation of pulmonary arterial hypertension (PAH) in premature calves by using lung-specific epithelial and endothelial biomarkers are needed. OBJECTIVE: To investigate the evaluation of PAH in premature calves with and without respiratory distress syndrome (RDS) by using lung-specific epithelial and endothelial biomarkers and determine the prognostic value of these markers in premature calves. ANIMALS: Fifty premature calves with RDS, 20 non-RDS premature calves, and 10 healthy term calves...

OBJECTIVE: To explore high-risk factors of respiratory distress syndrome (RDS) and to compare the clinical efficacy of calf pulmonary surfactant (PS) combined with budesonide suspension and poractant alfa injection in the treatment of RDS in premature infants. METHODS: A retrospective analysis was conducted. Preterm infants who were born in the obstetrics department of Liaocheng People's Hospital and admitted to the neonatal intensive care unit (NICU) within 24 hours from July 2016 to July 2020 were enrolled...

To determine how different constituents of pulmonary surfactant affect its phase behavior, we measured wide-angle x-ray scattering (WAXS) from oriented bilayers. Samples contained the nonpolar and phospholipids (N&PL) obtained from calf lung surfactant extract (CLSE), which also contains the hydrophobic surfactant proteins, SP-B and SP-C. Mixtures with different ratios of N&PL and CLSE provided the same set of lipids with different amounts of the proteins. At 37 °C, N&PL by itself forms coexisting Lα and Lβ phases...

When compressed by the shrinking alveolar surface area during exhalation, films of pulmonary surfactant in situ reduce surface tension to levels at which surfactant monolayers collapse from the surface in vitro . Vesicles of pulmonary surfactant added below these monolayers slow collapse. X-ray scattering here determined the structural changes induced by the added vesicles. Grazing incidence X-ray diffraction on monolayers of extracted calf surfactant detected an ordered phase. Mixtures of dipalmitoyl phosphatidylcholine and cholesterol, but not the phospholipid alone, mimic that structure...

The only known compositional change in the phospholipids (PL) of pulmonary surfactant in response to a physiologic stimulus occurs around the time of birth. In most species, the predominant anionic PL changes from phosphatidylinositol (PtdIns) to phosphatidylglycerol (PtdGro). Because prior studies have shown that the change in the headgroup itself is functionally insignificant, we tested the hypothesis that the PtdIns and PtdGro contain different diacyl pairs. Experiments used electrospray-ionization mass spectrometry to determine the molecular species in PtdIns, PtdGro, and phosphatidylcholine (PtdCho) in surfactant from newborn calves and cows...

Poractant alfa and Calsurf are two natural surfactants widely used in China for the treatment of neonatal respiratory distress syndrome, which are extracted from porcine and calf lungs, respectively. The purpose of this experimental study was to compare their in vitro characteristics and in vivo effects in the improvement of pulmonary function and protection of lung injury. The biophysical properties, ultrastructure, and lipid composition of both surfactant preparations were respectively analysed in vitro by means of Langmuir-Blodgett trough (LBT), atomic force microscopy (AFM), and liquid-chromatography mass-spectrometry (LC-MS)...

Calf pulmonary surfactant (CPS), which contains about 98% lipids and 2% hydrophobic surfactant proteins B (SP-B) and C (SP-C), has been used as a surfactant preparation for the clinical replacement therapy of respiratory distress syndrome (RDS). Characterization of SP-B and SP-C in CPS is informative for quality control and the evaluation of their biological activities. However, analysis of SP-B and SP-C is impeded by the high content of lipids in CPS. Here, we describe an integrated method by combining size exclusion chromatography (SEC)-based delipidation, SDS-PAGE separation, in-gel digestion and mass spectrometric analysis for comprehensive characterization and proteoform analysis of the extremely hydrophobic SP-B and SP-C in CPS...

To determine how different components affect the structure of pulmonary surfactant, we measured X-ray scattering by samples derived from calf surfactant. The surfactant phospholipids demonstrated the essential characteristics of the Lγ phase: a unit cell with a lattice constant appropriate for two bilayers, and crystalline chains detected by wide-angle X-ray scattering (WAXS). The electron density profile, obtained from scattering by oriented films at different relative humidities (70-97%), showed that the two bilayers, arranged as mirror images, each contain two distinct leaflets with different thicknesses and profiles...

AIM: This study aimed to study the effects of intratracheal instillation of budesonide on lung maturity of premature fetal rabbits. The developmental pattern of pulmonary alveoli in rabbits is similar to that in humans. METHOD: Fetal rabbits were taken out from female rabbits on the 28th day of pregnancy (full term = 31 days) by cesarean section (c-section). The fetal rabbits were divided into four groups: control (normal saline, NS), budesonide (budesonide, BUD), calf pulmonary surfactant for injection (pulmonary surfactant, PS), and calf pulmonary surfactant + budesonide for injection (pulmonary surfactant + budesonide, PS + BUD)...

Lung surfactant has been observed at all surfaces of the airway lining fluids and is an important contributor to normal lung function. In the conducting airways, the surfactant film lies atop a viscoelastic mucus gel. In this work, we report on the characterization of the tensiometric and phase domain behavior of lung surfactant at the air-liquid interface of mucus-like viscoelastic gels. Poly(acrylic acid) hydrogels were formulated to serve as a model mucus with bulk rheological properties that matched those of tracheobronchial mucus secretions...

BACKGROUND: Surfactant has been shown to be dysfunctional in ARDS, and exogenous surfactant has proven effective in many forms of neonatal and pediatric acute lung injury (ALI). In view of the positive results of our studies in children along with evidence that surfactant-associated protein B containing pharmaceutical surfactants might be more effective, we designed a multiinstitutional, randomized, controlled, and masked trial of calfactant, a calf lung surfactant, in adults and children with ALI/ARDS due to direct lung injury...

OBJECTIVE: To evaluate the efficacy of calf pulmonary surfactant (PS) in the treatment of respiratory distress syndrome (RDS) in late preterm and full-term infants. METHODS: A randomized controlled trial was designed to evaluate the efficacy of calf PS intratracheally given at different times and doses in infants with RDS who had a gestational age of ≥35 weeks and an oxygenation index (OI) of 10-20. The subjects were randomly assigned to treatment group 1 (n=58), treatment group 2 (n=58), and control group (n=59)...

OBJECTIVE: To explore the efficacy and safety of combined inflating lung and insufflating calf pulmonary surfactant under general anesthesia for treating postoperative intractable atelectasis. METHODS: From August 2006 to January 2013, 15 patients with obstinate postoperative atelectasis receiving pressure control lung expansion were enrolled. The bronchial cannula was intubated into the affected side to assist the expanding of the lung, and the calf pulmonary surfactant was insufflated selectively...

This paper reports the chemical synthesis and purification of a novel phospholipase-resistant C16:0, C16:1 diether phosphonoglycerol with structural analogy to ester-linked anionic phosphatidylglycerol (PG) in endogenous pulmonary surfactant. This diether phosphonoglycerol (PG 1) is studied for phospholipase A(2) (PLA(2)) resistance and for surface activity in synthetic exogenous surfactants combined with Super Mini-B (S-MB) peptide and DEPN-8, a previously-reported diether phosphonolipid analog of dipalmitoyl phosphatidylcholine (DPPC, the major zwitterionic phospholipid in native lung surfactant)...

Adsorption of pulmonary surfactant to an air-water interface lowers surface tension (γ) at rates that initially decrease progressively, but which then accelerate close to the equilibrium γ. The studies here tested a series of hypotheses concerning mechanisms that might cause the late accelerated drop in γ. Experiments used captive bubbles and a Wilhelmy plate to measure γ during adsorption of vesicles containing constituents from extracted calf surfactant. The faster fall in γ reflects faster adsorption rather than any feature of the equation of state that relates γ to surface concentration (Γ)...

Beta(2)-adrenergic agonists cause a release of pulmonary surfactant into lung airways. The surfactant phospholipids maintain the patency of the conducting airways, but this function is inhibited by plasma proteins entering an inflamed airway. The physical behavior of the surfactant can be studied with a pulsating bubble surfactometer and a capillary surfactometer. Calf lung surfactant extract was found to be inhibited by plasma proteins and by a lowering of temperature. Severe breathing difficulties and malfunctioning surfactant developed in BALB/c mice inhaling ozone or infected with respiratory syncytial virus, mainly as a result of proteins invading the airways...

The transmission of Mycobacterium tuberculosis (TB) requires extensive damage to the lungs to facilitate bacterial release into the airways, and it is therefore likely that the microorganism has evolved mechanisms to exacerbate its local pathology. This study examines the inhibitory effects of lipids extracted and purified chromatographically from TB on the surface-active function of lavaged bovine lung surfactant (LS) and a clinically relevant calf lung surfactant extract (CLSE). Total lipids from TB greatly inhibited the surface activity of LS and CLSE on the pulsating bubble surfactometer at physical conditions applicable for respiration in vivo (37 degrees C, 20 cycles/min, 50% area compression)...

BACKGROUND: This study examines the surface activity and resistance to phospholipase degradation of a fully-synthetic lung surfactant containing a novel diether phosphonolipid (DEPN-8) plus a 34 amino acid peptide (Mini-B) related to native surfactant protein (SP)-B. Activity studies used adsorption, pulsating bubble, and captive bubble methods to assess a range of surface behaviors, supplemented by molecular studies using Fourier transform infrared (FTIR) spectroscopy, circular dichroism (CD), and plasmon resonance...