RESUMEN
BACKGROUND: Infected acute necrotic collection (ANC) is a fatal complication of acute pancreatitis with substantial morbidity and mortality. Drainage plays an exceedingly important role as the first step in invasive intervention for infected necrosis; however, there is great controversy about the optimal drainage time, and better treatment should be explored. CASE SUMMARY: We report the case of a 43-year-old man who was admitted to the hospital with severe intake reduction due to early satiety 2 wk after treatment for acute pancreatitis; conservative treatment was ineffective, and a pancreatic pseudocyst was suspected on contrast-enhanced computed tomography (CT). Endoscopic ultrasonography (EUS) suggested hyperechoic necrotic tissue within the cyst cavity. The wall was not completely mature, and the culture of the puncture fluid was positive for A-haemolytic Streptococcus. Thus, the final diagnosis of ANC infection was made. The necrotic collection was not walled off and contained many solid components; therefore, the patient underwent EUS-guided aspiration and lavage. Two weeks after the collection was completely encapsulated, pancreatic duct stent drainage via endoscopic retrograde cholangiopancreatography (ERCP) was performed, and the patient was subsequently successfully discharged. On repeat CT, the pancreatic cysts had almost disappeared during the 6-month follow-up period after surgery. CONCLUSION: Early EUS-guided aspiration and lavage combined with late ERCP catheter drainage may be effective methods for intervention in infected ANCs.
RESUMEN
Astragaloside IV (AST) has been confirmed to have antiasthmatic effects. However, the underline mechanism is unclear. The study aimed to explore the treatment mechanism of AST based on autophagy of memory T cells. AST treatment significantly decreased the number of T effector cells in asthma mice blood and the nude mice that received AST-treated TCMs had relieved inflammation compared with the untreated group; meanwhile, we found that AST significantly decreased the autophagy level and inhibited OX40/OX40L signal pathway of lymphocytes. The results highlighted that AST regulated autophagy to inhibit differentiation of effector T-cell phenotype.
Asunto(s)
Asma , Autofagia , Inflamación , Saponinas , Linfocitos T , Triterpenos , Animales , Saponinas/farmacología , Asma/tratamiento farmacológico , Triterpenos/farmacología , Triterpenos/química , Ratones , Autofagia/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Inflamación/tratamiento farmacológico , Ratones Desnudos , Estructura Molecular , Transducción de Señal/efectos de los fármacos , Ratones Endogámicos BALB CRESUMEN
The lack of M-Fe-S (M = Mo or W) clusters incorporating a second period (2p) atom in the core has resulted in limited investigations and poor understanding of the physical and chemical properties of the M-Fe-S clusters closely related to the FeMo cofactor. In this work, systematic studies have been carried out to explore the chemical reactivities at the terminal ligand sites and the redox properties of a series of clusters comprising a [WFe3S3N] cubane core, based on the previously developed cluster [(Tp*)WFe3S3(µ3-NSiMe3)Cl3]1-. Substitutions of the terminal chlorides with ethanethiolate, methanethiolate, thiophenolate, p-thiocresolate and azide occurred smoothly, while the replacement of the chlorides with carbene ligands required the reduction of the precursor into [(Tp*)WFe3S3(µ3-NSiMe3)Cl3]2- first. The reduced cluster core could also be supported by thiophenolates as terminal ligands, but not thiolates or azides. It is remarkable that the thiophenolate ligated reduced cluster can be synthesized from the precursor [(Tp*)WFe3S3(µ3-NSiMe3)Cl3]1-via different synthetic routes, either reduction followed by substitution or substitution followed by reduction, either in situ or stepwise. This work indicates that terminal ligands contribute significantly to determine the chemical and physical properties of the clusters, even though they might affect the cluster core to a limited extent from a structural point of view, which raises the possibility of delicate control in regulating the physical/chemical properties of M-Fe-S clusters with a heteroleptic core incorporating 2p atom(s).
RESUMEN
The strength of phylogeographic breaks can vary among species in the same area despite being subject to the same geological and climate history due to differences in biological traits. Several important phylogeographic breaks exist around the Sichuan Basin in Southwest China but few studies have focused on wind-dispersed plants. Here, we investigated the phylogeographic patterns and the evolutionary history of Populus lasiocarpa, a wind-pollinated and wind-dispersed tree species with a circum-Sichuan Basin distribution in southwest China. We sequenced and analyzed three plastid DNA fragments (ptDNA) and eight nuclear microsatellites (nSSRs) of 265 individuals of P. lasiocarpa from 21 populations spanning the entire distribution range. Distribution patterns based on nSSR data revealed that there are three genetic groups in P. lasiocarpa. This is consistent with the three phylogeographic breaks (Sichuan Basin, the Kaiyong Line and the 105°E line), where the Sichuan basin acts as the main barrier to gene flow between western and eastern groups. However, the distribution pattern based on ptDNA haplotypes poorly matched the phylogeographic breaks, and wind-dispersed seeds may be one of the main contributing factors. Species distribution modelling suggested a larger potential distribution in the last glacial maximum with a severe bottleneck during the last interglacial. A DIYABC model also suggested a population contraction and expansion for both western and eastern lineages. These results indicate that biological traits are likely to affect the evolutionary history of plants, and that nuclear molecular markers, which experience higher levels of gene flow, might be better indicators of phylogeographic breaks.
RESUMEN
PURPOSE: There are limited studies on the use of bronchodilators for the treatment of bronchiectasis. This study investigated the efficacy of tiotropium in patients with bronchiectasis and airflow limitation. METHODS: This study was a prospective cohort study, including 169 patients with bronchiectasis and airflow limitation from 2015 to 2019. The clinical outcomes observed in our study were the effect of tiotropium on the frequency of moderate exacerbations, the time to the first severe exacerbation, and the annual decline in FEV1. RESULTS: After 12 months, the annual decline in the FEV1 after bronchodilator use was 27.08 ml or 42.9 ml per year in the group with or without tiotropium, respectively. Treatment with tiotropium was associated with a decreased risk of moderate exacerbation of bronchiectasis (Adjusted RR 0.618 95% CI 0.493-0.774; P < 0.005). The time to the first severe acute exacerbation of bronchiectasis in the tiotropium group was longer than the non-tiotropium group (Adjusted HR 0.333 95% CI 0.219-0.506; P < 0.001). CONCLUSION: In conclusion, prospective cohort study showed that tiotropium effectively ameliorated the annual decline in the FEV1, with a lower-risk rate of moderate exacerbations and prolonging the time to the first-time severe exacerbation in patients with bronchiectasis and airflow limitation.
Asunto(s)
Bronquiectasia , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Bromuro de Tiotropio/uso terapéutico , Estudios Prospectivos , Derivados de Escopolamina/uso terapéutico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Broncodilatadores/uso terapéutico , Resultado del TratamientoRESUMEN
The emergence of pseudorabies virus (PRV) variants brings serious harm to the swine industry, and its effective treatments are limited at present. As one of the probiotics, the Lactobacillus species have beneficial characteristics of regulating the balance of intestinal flora, inhibiting the growth of pathogenic bacteria and viruses' proliferation, and improving self-immunity. In this study, Lactobacillus plantarum HN-11 and Lactobacillus casei HN-12 were selected and identified through morphology observation, Gram stain microscopy, 16S rRNA sequencing analysis, and specific amplification of the recA gene and pheS gene. All tested isolates exhibited rapid adaptation to the different conditions, excellent acid, and bile tolerance, and sensitivity to Salmonella, Staphylococcus aureus, and Escherichia coli. The antibiotic susceptibility assay displayed the isolates sensitive to most antibiotics and resistant to Lincomycin and Norfloxacin. Moreover, the supernatants of HN-11 and HN-12 inhibited PRV proliferation in ST cells. The results of animal experiments showed that supplementing the challenged mice with the supernatants of Lactobacillus isolates in advance delayed the course of the disease. PRV was detected in the heart, liver, spleen, lung, kidney, and brain tissues of dead mice in the test groups, and its copies in the lungs were significantly decreased compared with the control mice (P < 0.05). These findings proved the advantages of L. plantarum and L. casei as potential probiotic cultures, which could provide a basis for its application in microecological preparations and functional formulations.
RESUMEN
Leukoaraiosis (LA) is commonly found in aging healthy people but its pathophysiological mechanism is not entirely known. Furthermore, there is still a lack of effective pathological biomarkers that can be used to identify the early stage of LA. Our aim was to investigate the white matter structural network in asymptomatic patients with the early stage of LA. Tractography data of 35 asymptomatic patients and 20 matched healthy controls (HCs) based on diffusion kurtosis imaging (DKI) were analysed by using graph theory approaches and tract-based spatial statistics (TBSS). Diffusion parameters measured within the ALAs and HCs were compared. Decreased clustering coefficient and local efficiency values of the overall topological white matter network were observed in the ALAs compared with those of the HCs. Participants in the asymptomatic group also had lower nodal efficiency in the left triangular part of the inferior frontal gyrus, left parahippocampal gyrus, right calcarine fissure and surrounding cortex, right temporal pole of the superior temporal gyrus and left middle temporal gyrus compared to the ALAs. Moreover, similar hub distributions were found within participants in the two groups. In this study, our data demonstrated a topologic efficiency abnormalities of the structural network in asymptomatic patients with leukoaraiosis. The structural connectome provides potential connectome-based measures that may be helpful for detecting leukoaraiosis before clinical symptoms evolve.
RESUMEN
This study shows that the supramolecular arrangement of proteins in nanoparticle structures predicts nanoparticle accumulation in neutrophils in acute lung inflammation (ALI). We observed homing to inflamed lungs for a variety of nanoparticles with agglutinated protein (NAPs), defined by arrangement of protein in or on the nanoparticles via hydrophobic interactions, crosslinking and electrostatic interactions. Nanoparticles with symmetric protein arrangement (for example, viral capsids) had no selectivity for inflamed lungs. Flow cytometry and immunohistochemistry showed NAPs have tropism for pulmonary neutrophils. Protein-conjugated liposomes were engineered to recapitulate NAP tropism for pulmonary neutrophils. NAP uptake in neutrophils was shown to depend on complement opsonization. We demonstrate diagnostic imaging of ALI with NAPs; show NAP tropism for inflamed human donor lungs; and show that NAPs can remediate pulmonary oedema in ALI. This work demonstrates that structure-dependent tropism for neutrophils drives NAPs to inflamed lungs and shows NAPs can detect and treat ALI.
Asunto(s)
Inflamación/patología , Pulmón/patología , Nanopartículas/química , Neutrófilos/patología , Proteínas/química , Enfermedad Aguda , Aglutinación/efectos de los fármacos , Animales , Anticuerpos/farmacología , Reactivos de Enlaces Cruzados/química , Dextranos/química , Humanos , Lipopolisacáridos , Liposomas , Pulmón/diagnóstico por imagen , Masculino , Ratones Endogámicos C57BL , Muramidasa/metabolismo , Neutrófilos/efectos de los fármacos , Proteínas Opsoninas/metabolismo , Electricidad Estática , Distribución Tisular/efectos de los fármacos , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Differential diagnosis of colorectal intramucosal tumors from invasive adenocarcinoma is important in clinical practice due to the different risks of lymph node metastasis and different treatment options. The phenomenon of a colorectal adenoma with part of the gland entering the submucosa is known as pseudoinvasion of the adenoma, which is a major challenge for pathological diagnosis. It is essential to raise awareness of colorectal adenoma with submucosal pseudoinvasion clinically to avoid overtreatment. CASE SUMMARY: We describe a case of rectal adenoma with submucosal pseudoinvasion in a 48-year-old man. The patient was admitted to Jinhua People's Hospital due to a change in stool habit for 5 d. We performed colonoscopy, and the results suggested a submucosal bulge approximately 1.0 cm × 1.0 cm in size in the rectum 8 cm from the anal verge, with red surface erosion. Ultrasound colonoscopy was also performed and a homogeneous hypoechoic mass about 0.52 cm × 0.72 cm in size was seen at the lesion, protruding into the lumen with clear borders and invading the submucosa. Endoscopic surgery was then performed and the pathological specimen showed a tubular adenoma with high-grade intraepithelial neoplasia (intramucosal carcinoma) involving the adenolymphatic complex. In addition, we performed a literature review of rectal tubular adenoma with submucosal pseudoinvasion to obtain a deeper understanding of this disease. CONCLUSION: The aim of this study was to improve awareness of this lesion for clinicians and pathologists to reduce misdiagnosis.
RESUMEN
The aim of this study was to investigate the abnormities in functional connectivity (FC) within each modular network and between modular networks in patients with systemic lupus erythematosus (SLE). Twelve meaningful modular networks were identified via independent component analysis from 41 patients and 40 volunteers. Parametric tests were used to compare the intra- and intermodular FC between the groups. Partial correlation analysis was used to seek the relationships between abnormal FCs and the clinical data. Compared to the controls, SLE patients showed decreased intramodular FC in the anterior default mode network (aDMN), posterior default mode network (pDMN), ventral attention network (VAN), and sensorimotor network (SMN) and increased intramodular FC in the medial visual network (mVN) and left frontoparietal network. In addition, SLE patients showed decreased intermodular FC between the SMN and the lateral visual network (lVN), between the SMN and the VAN, and between the pDMN and the lVN and exhibited increased intermodular FC between the SMN and the salience network (SAN), between the pDMN and the SAN, and between the aDMN and the VAN. Moreover, we found several correlations among the abnormal FCs and the Mini-Mental State Examination in SLE patients. Mild cognitive impairment is compensated by the hyperconnectivity between the aDMN and the VAN, while severe cognitive impairment tends to be compensated by the hyperconnectivity between the SMN and the SAN. The FC value between the SMN and the SAN and between the aDMN and the VAN may serve as neuroimaging markers for monitoring cognitive progression in SLE patients.
Asunto(s)
Disfunción Cognitiva , Lupus Eritematoso Sistémico , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Disfunción Cognitiva/diagnóstico por imagen , Humanos , Lupus Eritematoso Sistémico/diagnóstico por imagen , Imagen por Resonancia Magnética/métodosAsunto(s)
Fascitis , Fibroma , Paniculitis , Diagnóstico Diferencial , Fascitis/diagnóstico , Fascitis/genética , HumanosRESUMEN
Medroxyprogesterone acetate (MPA) is one of the most widely used contraceptives in the world. Epidemiologic studies have uncovered a possible link between the use of MPA and an increased risk of HIV-1 transmission. However, the understanding of the mechanism is still limited. Our previous publication demonstrated that the lysosomal activity in human vaginal epithelial cells attenuated the trafficking of viral particles during HIV-1 transcytosis. In this study, we show that treating human primary cervical epithelial cells with MPA led to a reduction in lysosomal activity. This reduction caused an increase in the intracellular HIV-1 accumulation and, consequently, an increase in viral release. Our study uncovers a novel mechanism by which MPA enhances HIV-1 release in primary cervical epithelial cells, thus providing vital information for HIV intervention and prevention.
RESUMEN
Using resting-state functional magnetic resonance imaging and graph theory approaches to investigate the topological characteristics of functional networks and their potential correlations with clinical information in patients with systemic lupus erythematosus (SLE). A total of 41 patients and 35 volunteers were consecutively recruited. Detailed clinical data of all participants were recorded. All participants underwent a resting-state functional magnetic resonance imaging examination. Functional networks were constructed by a Pearson correlation matrix of 116 brain regions. The topological properties were analyzed by graph theory. Parametric tests were used to compare the topological properties between the groups. Partial correlation analysis was used to identify relationships between the abnormal topological properties and the clinical data. The nodal network metrics were abnormal in the SLE patients compared to the controls. Decreased nodal efficiency was identified in the right insula, bilateral putamen, and bilateral Heschl's gyrus in the SLE patients. Decreased degree centrality was also found in the right amygdala and bilateral Heschl's gyrus. In addition, the SLE patients showed decreased network functional connectivity (FC) between several regions, particularly between the basal ganglia and the cerebellum. Moreover, FC values between the right putamen and vermis 6 were positively correlated with Mini-Mental State Examination scores. The nodal efficiency and the degree centrality values in the left Heschl's gyrus were both positively correlated with the course of the disease. The topological structure of the functional network was apparently abnormal in SLE patients. FC values between the right putamen and vermis 6 may serve as a neuroimaging marker for evaluating the progressive cognitive decline in SLE patients. Decreased synergy between the basal ganglia region and the cerebellum in the extrapyramidal system may be one cause of cognitive dysfunction in SLE patients.
Asunto(s)
Lupus Eritematoso Sistémico , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Corteza Cerebral , Humanos , Lupus Eritematoso Sistémico/diagnóstico por imagenRESUMEN
The transcription factor Woolly (Wo) and its downstream gene CycB2 have been shown to regulate trichome development in tomato (Solanum lycopersicum). It has been demonstrated that only the gain-of-function allele of Slwo (SlWoV, the Slwo woolly motif mutant allele) can increase the trichome density; however, it remains unclear why the two alleles function differently in trichome development. In this study, we used Nicotiana benthamiana as a model and cloned the homologues of Slwo and SlCycB2 (named Nbwo and NbCycB2). We also constructed a Nbwo gain-of-function allele with the same mutation site as SlWoV (named NbWoV). We found that both Nbwo and NbWoV directly regulate NbCycB2 and their own expression by binding to the promoter of NbCycB2 and their own genomic sequences. As form of a feedback regulation, NbCycB2 negatively regulates trichome formation by repressing Nbwo activity at the protein level. We also found that mutations in the Nbwo woolly motif can prevent repression of NbWoV by NbCycB2, which results in a significant increase in the amount of active Nbwo proteins and in increases in trichome density and the number of branches. Our results reveal a novel reciprocal regulation mechanism between NbCycB2 and Nbwo during trichome formation in N. benthamiana.
Asunto(s)
Proteínas de Arabidopsis , Solanum lycopersicum , Proteínas de Arabidopsis/metabolismo , Retroalimentación , Regulación de la Expresión Génica de las Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Tricomas/metabolismoRESUMEN
BACKGROUND: The clinical efficacy of fentanyl for pain control differs greatly across individuals. The purpose of this study was to investigate the impact of CYP3A4*1G polymorphism including wild-type homozygote (CYP3A4*1/*1, GG), mutant heterozygote (CYP3A4*1/*1G, GA), and mutant homozygote (CYP3A4*1G/*1G, AA) on fentanyl analgesia in Chinese patients undergoing hysteroscopy by the assessment of analgesia nociception index (ANI). METHODS: A total of 200 gynecologic patients scheduled for elective hysteroscopy under general anesthesia at Peking University People's Hospital from May to December in 2017 were enrolled in this study. Venous blood was withdrawn for genotyping of CYP3A4*1G before operation. Fentanyl 1 µg/kg was administered preoperatively followed by target-controlled infusion of propofol for induction and maintenance. Intraoperative analgesic efficacy of fentanyl was assessed by ANI monitoring at T0 (entering room), T1 (cervical dilation), T2 (start of cervical aspiration), and T3 (end of cervical aspiration) time points. The duration of propofol infusion and total dosage of propofol were recorded as well. RESULTS: The patients were divided into three groups according to CYP3A4*1G polymorphism, including 143 in GG group, 47 in GA group, and 10 in AA group. There was no significant difference in clinical demographics among three groups. The frequency of CYP3A4*1G variant alleles accounted for 16.8% and the distribution of variant alleles was consistent with Hardy-Weinberg equilibrium. Using a multilevel model, ANI values at T1 (63.81 ± 19.61), T2 (63.63 ± 17.82), and T3 (65.68 ± 17.79) were significantly lower than that at T0 (77.16 ± 12.93) in the study population (F = 23.50, P < 0.001), suggesting that higher levels of pain at T1, T2, and T3 than T0. Patients with GG genotype showed significantly lower ANI than those with GA or AA genotypes during hysteroscopy under the same dose of fentanyl. CONCLUSION: CYP3A4*1G polymorphism associated with the analgesic efficacy of intraoperative fentanyl in the patients undergoing hysteroscopy under general anesthesia.
Asunto(s)
Anestésicos Intravenosos/uso terapéutico , Citocromo P-450 CYP3A/genética , Fentanilo/uso terapéutico , Histeroscopía , Adolescente , Adulto , Femenino , Genotipo , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Polimorfismo Genético/genética , Adulto JovenRESUMEN
General control non-derepressible-2 (GCN2) is a ubiquitous protein kinase that phosphorylates the α subunit of the eukaryotic initiation factor, eIF2, preventing the initiation of a new cycle of protein synthesis, subsequently reducing the global protein biosynthesis. GCN2 can also regulate the response of plants to biotic and abiotic stresses. In this study, two GCN2 homologs, NtGCN2-1 and NtGCN2-2, were cloned from Nicotiana tabacum, and were predicted to have been derived from their progenitors in N. tomentosiformis and N. sylvestris, respectively. The phosphorylation of NteIF2α could be activated by promoting the expression of NtGCN2 with plant hormones, including salicylic acid (SA), azelaic acid (AZA), methyl jasmonate (MeJA), and by imposition of different stresses (Bemisia tabaci infection, drought, and cold), indicating that NtGCN2 is involved in the response of plants to multiple biotic and abiotic stresses. We also observed that the overexpression of NtGCN2-1 significantly influenced different physiological processes. It promoted seed germination and root elongation. The content of total soluble sugars and reducing sugars were decreased, whereas those of chlorophyll a and b were increased in the GCN2 overexpressing plants. In addition, the overexpressing plants had lower content of reactive oxygen species and exhibited higher antioxidant activities. These physiological alterations could be attributed to the changes in the endogenous phytohormones, decrease in the SA and abscisic acid content, and accumulation of MeJA and AZA. It indicated that the overexpression of NtGCN2 in tobacco, stimulated the plant defense responses via phosphorylation of NteIF2α and regulation of plant hormones, and changes in the antioxidant ability and plant nutrient status.
RESUMEN
BACKGROUND: Brain consists of plenty of complicated cytoarchitecture. Gaussian-model based diffusion tensor imaging (DTI) is far from satisfactory interpretation of the structural complexity. Diffusion kurtosis imaging (DKI) is a tool to determine brain non-Gaussian diffusion properties. We investigated the network properties of DKI parameters in the whole brain using graph theory and further detected the alterations of the DKI networks in Alzheimer's disease (AD). METHODS: Magnetic resonance DKI scanning was performed on 21 AD patients and 19 controls. Brain networks were constructed by the correlation matrices of 90 regions and analyzed through graph theoretical approaches. RESULTS: We found small world characteristics of DKI networks not only in the normal subjects but also in the AD patients; Grey matter networks of AD patients tended to be a less optimized network. Moreover, the divergent small world network features were shown in the AD white matter networks, which demonstrated increased shortest paths and decreased global efficiency with fiber tractography but decreased shortest paths and increased global efficiency with other DKI metrics. In addition, AD patients showed reduced nodal centrality predominantly in the default mode network areas. Finally, the DKI networks were more closely associated with cognitive impairment than the DTI networks. CONCLUSIONS: Our results suggest that DKI might be superior to DTI and could serve as a novel approach to understand the pathogenic mechanisms in neurodegenerative diseases.
RESUMEN
OBJECTIVE: Progressive weakness of respiratory muscles remains one of the leading causes of death among patients with Duchenne muscular dystrophy (DMD). Currently, there are few pulmonary function data among Chinese DMD patients. This study was carried out to evaluate the sniff nasal inspiratory pressure (SNIP) change among a group of Chinese DMD patients, and compare it with the SNIP value of patients with neuromuscular disorders in other countries. METHODS: SNIP data were collected in three research groups that consists of 581 subjects: 125 DMD boys who have taken steroid (Age 5.0-13.3, DMD-steroid group), 145 DMD steroid-naive boys (Age 5.0-13.9, DMD-nonsteroid group), and 311 healthy controls (Age 5.0-14.0, Control group). RESULTS: The SNIP for DMD-nonsteroid group, DMD-steroid group and Control group were: 56.5 (±14.3)â¯cm H2O,66.4 (±15.5)â¯cm H2O and 78.9 (±21.5) respectively. The SNIP in the DMD-nonsteroid group became significantly different from that of the healthy controls since age 7.0-8.9. The significant difference of SNIP between DMD-steroid group and DMD-nonsteroid group at age 7.0-10.9. The peak value of SNIP in the DMD-nonsteroid group appeared at age 8.7, and decreased dramatically thereafter, while in DMD-steroid group and the Control group peaked at 10.2â¯years and 12.2â¯years respectively. There was a bit difference between SNIP in this group and that in previous researches which may be due to geographical distribution and ethnic backgrounds. CONCLUSION: This study strengthens the previous findings that SNIP can be used to evaluate respiratory dysfunction during the early stage of young patients with neuromuscular disorders, and demonstrates that steroid is effective in slowing the decrease of SNIP in this group of Chinese DMD boys.