Relationship between plasma SP-A expression level and disease stage in silicosis patients / 上海预防医学

ObjectiveTo investigate the relationship between plasma surfactant protein⁃A （SP⁃A） expression level and silicosis progression， and to provide early evidence for exploring whether SP⁃A can be used as a biomarker for clinical monitoring of silicosis disease progression. MethodsWe recruited 187 silicosis patients in Guangdong Province hospital for occupational disease prevention and treatment between November， 2019 and November，2020. Their peripheral venous blood samples were collected for the plasma isolation. The level of pulmonary SP⁃A was detected by enzyme-linked immunosorbent assay. ResultsThere was a statistically significant difference in the level of SP⁃A among the silicosis groups （P<0.05）， and the plasma SP-A level of the silicosis patients in stage Ⅲ was higher than that in stage Ⅰ and stage Ⅱ （P<0.05）. Smoking had effect on plasma SP⁃A levels， Age， working years and drinking had no effect on plasma SP⁃A levels. ConclusionThe expression level of SP⁃A in the plasma of silicosis patients is increased， which has a certain correlation with the disease stage， and plays a certain early warning role in the occurrence and development of silicosis， and may be a potential biomarker for the diagnosis and prognosis of silicosis.

Seguridad del tratamiento con surfactante pulmonar en el síndrome de dificultad respiratoria aguda en niños / Safety of pulmonary surfactant therapy in acute respiratory distress syndrome in children

RESUMEN Introducción: Los surfactantes pulmonares junto a otras medidas terapéuticas constituyen un tratamiento de elección en diversas afecciones respiratorias. Objetivo: Demostrar la seguridad del tratamiento con Surfacen® en el síndrome de dificultad respiratoria aguda en niños. Materiales y Métodos: Ensayo clínico fase III multicéntrico, abierto, controlado y aleatorizado con dos grupos de tratamiento. El Grupo A recibió tratamiento convencional de oxigenación y ventilación mecánica combinado con Surfacen® en dosis de 100 mg cada ocho horas durante tres días. El Grupo B recibió tratamiento convencional. Se incluyeron niños entre los 28 días de nacido hasta 18 años de edad, de cualquier sexo, con diagnóstico de síndrome de dificultad respiratoria aguda. Se identificó y cuantificó la aparición de eventos adversos, intensidad, actitud seguida ante su aparición, resultado, relación de causalidad y mortalidad al día 28. Resultados: Se incluyeron 42 niños: 20 en el grupo A y 22 en el grupo B. En el grupo A se reportaron 23 eventos adversos en nueve pacientes y en el grupo B, 97 eventos adversos en 18 pacientes. La hipertensión arterial fue el evento adverso más frecuente. En el grupo A, 73,9% de los eventos adversos se manifestaron con intensidad severa, 86,9 % se mantuvo sin cambios frente al medicamento, 73,9 % tuvo causalidad remota respecto al surfactante. La mortalidad al día 28 fue de 41,5 %; en el grupo A, 20 % y en el grupo B, 62%. Conclusiones: Surfacen® fue bien tolerado y seguro al notificarse un número reducido de eventos adversos relacionados con su administración.

ABSTRACT Introduction: Pulmonary surfactants, together with other therapeutic measures, constitute a treatment of choice for various respiratory conditions. Objective: To demonstrate the safety of the treatment with Surfacen® in acute respiratory distress syndrome in children. Material and Methods: A multicenter, open, controlled, randomized Phase III clinical trial with two treatment groups. Group A received conventional oxygen therapy and mechanical ventilation combined with Surfacen® at a dosage of 100 mg every eight hours for three days. Group B received conventional treatment. Children 28 days of life to 18 years of age, of either sex, with the diagnosis of acute respiratory distress syndrome were included. The occurrence of adverse events, intensity, attitude followed after the appearance, outcome, and relationship between causality and mortality at day 28 were identified and quantified. Results: A total of 42 children were included: twenty children in group A and twenty-two ones in group B. In group A, 23 adverse events were reported in nine patients, while 97 adverse events were reported in 18 patients from group B. Hypertension was the most frequent adverse event. In group A, 73.9 % of adverse events of severe intensity were reported, 86.9 % remained unchanged after the administration of the drug, and 73.9 % had a remote causality with respect to the surfactant. Mortality at day 28 was 41.5 %; 20 % in group A, and 62 % in group B. Conclusions: Surfacen® was safe and well tolerated since a small number of adverse events related to its administration were reported.

Asociación molecular y función del agente tensioactivo pulmonar de ternera / Molecular association and function of calf lung surfactant

El agente tensioactivo pulmonar es un material compuesto de fosfolípidos, lípidos neutros y proteínas que se encuentra en la superficie alveolar de los pulmones y facilita la ventilación alveolar. La organización molecular de los componentes del agente tensioactivo aislado de pulmones de ternera fue analizada por calorimetría diferencial de barrido y por dispersión dinámica de luz y posteriormente comparada con los componentes organizados en liposomas uni y multilamelares; además, se probó la actividad de superficie al desarrollar en cobayos el síndrome de dificultad respiratoria. Los estudios de calorimetría mostraron que las interacciones lípido-proteína fueron considerablemente abatidas en el agente tensioactivo nativo, en comparación con las del agente tensioactivo en forma de liposomas uni o multilamelares. Los experimentos de dispersión dinámica de luz indicaron que el agente tensioactivo nativo tiene forma fibrilar con interacciones limitadas entre lípidos y proteínas, lo que sugiere que se encuentra organizado en una estructura en forma de reja formando una película de estructura estable. Los resultados obtenidos resaltan la importancia de la organización molecular del agente tensioactivo. Cuando éste fue usado para tratar a los animales con síndrome de dificultad respiratoria, los valores del pH arterial y de PaCO2 mejoraron casi hasta alcanzar los valores normales; cuando se utilizó el agente tensioactivo reconstituído como liposomas uni o multilamelares, los animales no se recuperaron. Es importante enfatizar que el método seguido en el protocolo de aislamiento del agente tensioactivo pulmonar de ternera permitió obtenerlo en una forma fisiológicamente activa.

Surfactant, a highly surface-active material composed of phospholipids, neutral lipids and proteins, lines the lungs' alveolar surface facilitating alveolar ventilation. The molecular organization of surfactant components isolated from calf-lungs was analyzed by differential-scanning calorimetry and dynamic light-scattering, and subsequently compared to surfactant components organized in uni and multilamellar liposomes. The respiratory distress syndrome developed in adult guinea pigs was used for assessing surfactant activity. Calorimetry studies showed that lipid-protein interactions were considerably abated in native surfactant as compared to those of surfactant in uni or multi-lamellar liposomes. Light-scattering experiments indicated that native surfactant has a fibrillar shape with limited lipid-protein interactions, suggesting that it is organized in a lattice-like structure forming a stable film. These findings underscore the importance of the native molecular organization of surfactant. When surfactant reconstituted as uni- or multilamellar liposomes was administred to animals under respiratory distress, they did not recover. In contrast, when native surfactant was used to treat sick animals, arterial pH and PaCO2 values improved, almost reaching normal values. It is important to emphasize that fewer steps in the protocol for isolation of calf lung surfactant made it possible to obtain it in a physiologically active molecular form.

Association of SP-D, MBL and I-NOS genetic variants with pulmonary tuberculosis.

Background: Pulmonary tuberculosis is caused by Mycobacterium tuberculosis . It is a multifactorial disease with both host as well as pathogen factors contributing to susceptibility and protection from the disease. Various reports have highlighted important roles of lung surfactant protein D (SP-D), mannan-binding lectin (MBL) and I-NOS in innate immune defense against M. tuberculosis Aims : The present study investigated the role of polymorphisms in three candidate genes encoding Lung surfactant protein D, Mannan binding lectin and Inducible Nitric oxide synthase, in susceptibility and protection to pulmonary tuberculosis. Settings and Design : A case-control association study of SNP's in lung surfactant protein D (SP-D), mannan-binding lectin (MBL) and I-NOS with pulmonary tuberculosis in Indian population was carried out. This involved sequencing of all the coding exons of lung surfactant protein D (SP-D) , while, exon 1 (collagen region) and exon 4 (carbohydrate recognition domain) of mannan-binding lectin (MBL) and exons 2, 8 and 16 of I-NOS and their flanking intronic regions for single nucleotide polymorphisms in DNA samples isolated from 30 pulmonary tuberculosis patients and 30 controls of Indian population. Statistical analysis: Various allele frequencies were calculated using online two by two table (home.clara.net/sisa/). Odds ratio and P values were calculated at 95% confidence interval (CI). Results : A total of fourteen single nucleotide polymorphisms (5 in SP-D , 5 in MBL and 4 in I-NOS ) were observed of which four (G459A SP-D , G274T I-NOS , G1011A and T357G MBL ) have not been reported earlier. Four single nucleotide polymorphisms viz. G459A of exon 7 of SP-D ( P =0.00, odds ratio (OR) = 4.96, 2.18 P = 0.00 or= 3.85 1.66 P =0.00 or=4.04, 2.20< OR<7.42) and G274T of intron 16 of I-NOS ( P =0.00 or=4.46, 2.40 Conclusion: The present study has led to identification of 4 SNP's in SP-D , MBL and I-NOS associated with pulmonary tuberculosis in Indian population.

Comparison of Surfacten Versus Newfacten for the Treatment of Respiratory Distress Syndrome

PURPOSE: This study was undertaken to determine the comparative efficacy between Surfacten and Newfacten in the early course of respiratory distress syndrome, ventilatory parameters, mortality and complications of RDS. METHODS: For the period of March 1998 to August 1999, total 60 neonates with RDS were treated with Surfacten (n=30) or Newfacten (n=30) at 2 different hospitals. Patients were enrolled for the trial if the following criteria were met; (1) age less than 24 hours; (2) birth weight between 800 gm and 2,500 gm; (3) clinical and radiographic findings consistent with RDS; (4) respiratory distress severe enough to require endotracheal intubation and mechanical ventilation; (5) a written informed consent by a parent. Infants were not eligible if they had a congenital anomaly or proven chromosomal anomaly. Two groups were treated with the equal doses of Surfacten and Newfacten via identical method and the various ventilator parameters, mortality and complications of RDS were compared. RESULTS: Surfacten was administered at 5.8 5.5 hour after birth and Newfacten was administered at 5.9 5.4 hour after birth. There were no differences in birth weight, gestational age in between 2 study groups. Ventilator parameters such as FiO2, MAP, VI, a/APO2 were measured in both groups and the differences were not statistically significant. There were no differences in the incidence of BPD, PDA, IVH, NEC, pneumothorax, pulmonary hemorrhage and ROP between two groups. There were no differences in mortality, the duration of ventilator care, and oxygen therapy between two groups. CONCLUSION: The effectiveness of Newfacten was comparable to that of Surfacten in terms of its efficacy in the treatment of RDS, complications, and mortality.

Evaluation of a lipid extract surfactant isolated from foam from adult sheep lung lavage

A simple and inexpensive method of isolating surfactant was devised. The in vivo function of surfactant isolated from saline alveolar washes of adult sheep lungs by foam formation using nitrogen gas was evaluated. The foam was organic solvent extracted with chloroform:methanol:saline (2:1:1 v/v) either once or twice. Part of each lipid extract surfactant (LES) was autoclaved. The total phosphorus (TP) and saturated phosphatidylcholine (sat PC) measurements were used to quantify these phospholipids in the LES. The mean sat PC:TP ratio was 0.54 and there were no changes with sterilization. to evaluate in vivo function, surfactant deficient preterm rabbits were treated intratracheally with either 100 mg/kg of the isolated sheep surfactant extracted twice with chloroform:methanol (LES-2), surfactant extracted only once (LES- 1), 4 ml/kg Survanta (S), or air (control, Cx). The rabbits were then ventilated with dital volumes of 8 ml/kg and 3 cm H20 positive and expiratory pressure (PEEP). Ventilation pressures (peak inspiratory pressure-PIP in cm H20, mean +/- SE) of animals treated with LES-2 (14.4 +/- 0.7) were lower (p 0.01) than Cx (22.8 + 0.5) and LES-1 (19.5 + 0.6), and not different from S (14.6 +/- 1.1). Dynamic compliances (ml/cmH20/kg) in animals treated with LES-2 (0.6 +/- 0.0) were higher (p 0.01) than Cx (0.4 +/- 0.0) and LES-1 (0.4 +/- 0.0), and not different from S (0.6 +/- 0.1). The initial inflation pressure from pressure-volume curve measurements was lowest for LES-2 treated animals (p0.01 at 20cm H20). Survanta and LES-2 treated animals retained more volume on deflation than Cx and LES-1 animals (p 0.01 at 0 cm H20). The ventilation and pressure-volume curve measurements for the autoclaved LES and non-autoclaved LES were similar. Based on the invivo performance of the LES, recommendations are made for improvements of the isolation procedure. (Author)

Clinical Trial of Domestically Developed Bovine Lung Surfactant YY-38 in Neonatal Respiratory Distress Syndrome

PURPOSE: We previously reported modified bovine lung surfactant YY-38(Newfactan ) had a low surface tension, good hysteresis, and exhibited good pressure-volume curve in animal experiment(J Korean Pediatr Asso 1997;40:771-85). We performed multicenter clinical trial of Newfactan in neonatal RDS. METHODS: Seventy-seven infants with RDS(GA 31.8+/-2.9 wks and BW 1,809+/-592 gm) in 4 NICU were enrolled. After administration of Newfactan , we analyzed ventilator parameters and outcomes in 71 infants excluding mortality cases(n=6), and also compared risk factors between response(n=53) and redosing group(n=18). RESULTS: Newfactan was administered at 6.8+/-7.2 hr after birth. Ventilator parameters such as FiO2, alveolar-arterial oxygen difference(a-A PO2) and oxygenation index(OI) except mean airway pressure(MAP) were significantly improved from six hours after administration. All parameters were improved at 24 hours after administration and persisted for 5 days. Outcomes were as follows; PDA(n=24), BPD(n=16), IVH(n=13), sepsis(n=9), ROP(n=7), pneumothorax(n=4) NEC(n=3), PIE(n=2), and pulmonary hemorrhage(n=1). All patients survived 30 days after birth. Redosing rate was 25%. The incidence of PDA was greater in redosing(56%) than in response group(26 %)(P=0.025). CONCLUSION: In prospective multicenter clinical trial, Newfactan was effective in the treatmentof RDS.

Physical and Biological Activity of Domestic Product of Modified Bovine Lung Surfactant

PURPOSE: Neonatal respiratory distress syndrome is caused by the deficiency of lung surfactant in premature babies. For the treatment of RDS at present surfactants such as Surfacten (Tokyo-Tanabe Co., Japan) and Exosurf (Wellcome Co., USA) are used. As awarded the grant from the Ministry of Science and Technology for a model research project of Medium-Technology program, we have modified (supplemented) the bovine lung extracts to get YY-38, for which we have performed physical and biological activities. METHODS: For physical properties, we performed stable microbubble test (SMR) and measured surface tension lowering activity using a pulsating bubble surfactometer. Minimum and maximum surface tensions measured at 1 and 5 minutes gave surface tension-surface area diagrams, from which compressibility at surface tension 10mN/m was also calculated. As to the biological activity, we used premature rabbit fetuses as a model for the study of pressure-lung volume relationship. The lung pathology was examined on the lung tissues subsequently obtained, and aerated area ratios were calculated based on the area measured by an image analyzer. RESULTS: The minimum surface tensions of YY-38 at 1 and 5 minutes for all different concentrations were low at 10mN/m, while the maximum surface tensions ranged from 33.01mN/m to 41.07mN/m. The surface tension-surface area curve showed a definite hysteresis at 1 and 5 minutes for all concentrations, and the surface tension fell below 10mN/m with 20% surface area compression. The compressibilities at surface tension 10mN/m at 5minutes for all concentrations were all below 0.02. In animal experiments, the mean lung volume of premature rabbit fetuses was inflated to 80.9ml/kg at maximum 30cmH2O, while the lung volume was maintained at 38.3mg/kg when the lung was deflated to 5cmH2O. The overall aerated area ratio was 45.4%. CONCLUSIONS: YY-38 formed sufficient amount of stable microbubbles and had a surface tension low enough to maintain alveolar stability and to exhibit a good hysteresis curve. In animal experiments it helped the expansion of premature lungs during inspiratory phase and was effective in the prevention of collapse during expiratory phase.