Biomedical subjects

Fang Gao

Publications and source records attributed to Fang Gao.

At least 19 recordsLinked to original sources

PubMed2006

Differential regulation of myofilament protein isoforms underlying the contractility changes in skeletal muscle unloading.

Weight-bearing skeletal muscles change phenotype in response to unloading. Using the hindlimb suspension rat model, we investigated the regulation of myofilament protein isoforms in correlation to contractility. Four weeks of continuous hindlimb unloading produced progressive atrophy and contractility changes in soleus but not extensor digitorum longus muscle. The unloaded soleus muscle also had decreased fatigue resistance. Along with the decrease of myosin heavy chain isoform I and IIa and increase of IIb and IIx, coordinated regulation of thin filament regulatory protein isoforms were observed: gamma- and beta-tropomyosin decreased and alpha-tropomyosin increased, resulting in an alpha/beta ratio similar to that in normal fast twitch skeletal muscle; troponin I and troponin T (TnT) both showed decrease in the slow isoform and increases in the fast isoform. The TnT isoform switching began after 7 days of unloading and TnI isoform showed detectable changes at 14 days while other protein isoform changes were not significant until 28 days of treatment. Correlating to the early changes in contractility, especially the resistance to fatigue, the early response of TnT isoform regulation may play a unique role in the adaptation of skeletal muscle to unloading. When the fast TnT gene expression was upregulated in the unloaded soleus muscle, alternative RNA splicing switched to produce more high molecular weight acidic isoforms, reflecting a potential compensation for the decrease of slow TnT that is critical to skeletal muscle function. The results demonstrate that differential regulation of TnT isoforms is a sensitive mechanism in muscle adaptation to functional demands.

Actin Cytoskeleton↗

PubMed2006

A study of the relationship between environmental contamination with methicillin-resistant Staphylococcus aureus (MRSA) and patients' acquisition of MRSA.

OBJECTIVE: The study aimed to examine the presence of methicillin-resistant Staphylococcus aureus (MRSA) in the environment and its relationship to patients' acquisition of MRSA. DESIGN: A prospective study was conducted in a 9-bed intensive care unit for 14 months. At every environmental screening, samples were obtained from the same 4 sites in each bed space. Patients were screened at admission and then 3 times weekly. All environmental and patient strains were typed using pulsed-field gel electrophoresis. RESULTS: MRSA was isolated from the environment at every environmental screening, when both small and large numbers of patients were colonized. Detailed epidemiological typing of 250 environmental and 139 patient isolates revealed 14 different pulsed-field gel electrophoresis profiles, with variants of EMRSA-15 being the predominant type. On only 20 (35.7%) of 56 occasions were the strains isolated from the patients and the strains isolated from their immediate environment indistinguishable. There was strong evidence to suggest that 3 of 26 patients who acquired MRSA while in the intensive care unit acquired MRSA from the environment. CONCLUSIONS: This study reveals widespread contamination of the hospital environment with MRSA, highlights the complexities of the problem of contamination, and confirms the need for more-effective cleaning of the hospital environment to eliminate MRSA.

Cross Infection↗

PubMed2006

Role of nonbronchoscopic lavage for investigating alveolar inflammation and permeability in acute respiratory distress syndrome.

OBJECTIVE: Nonbronchoscopic bronchoalveolar lavage is often used as an alternative to bronchoscopic bronchoalveolar lavage in the diagnosis of ventilator-associated pneumonia. We have previously reported an improved safety profile for nonbronchoscopic lavage in patients with lung injury, suggesting that this may be a better technique in this patient group. The objective of this study was to determine whether nonbronchoscopic lavage could be used as an alternative to bronchoscopic lavage for the assessment of alveolar permeability and inflammation in patients at risk for acute respiratory distress syndrome (ARDS) or with ARDS. DESIGN: Prospective randomized crossover trial. PATIENTS: Intubated patients with ARDS or at risk of ARDS. INTERVENTIONS: Bronchoscopic and nonbronchoscopic lavage in the same patient, 15 mins apart. MEASUREMENTS AND MAIN RESULTS: Twenty-one patients with ARDS and 20 patients at risk of ARDS were recruited and underwent nonbronchoscopic and bronchoscopic lavage in randomized order. Despite similar volumes of lavage fluid, nonbronchoscopic lavage had fewer cells and an increased ratio of bronchial epithelial cells to macrophages. Although average concentrations of myeloperoxidase and total protein, the protein permeability index, and the epithelial-lining fluid volume were similar with the two techniques and demonstrated moderate linear associations, Bland and Altman analysis revealed poor comparability, with substantial side-to-side variability and wide 95% limits of agreement. Furthermore, unlike bronchoscopic lavage, nonbronchoscopic lavage was unable to differentiate between patients with ARDS and those at risk of ARDS. CONCLUSIONS: Nonbronchoscopic lavage is not comparable to bronchoscopic lavage and as such cannot be used as an alternative to bronchoscopic lavage for assessing alveolar inflammation in patients with ARDS.

Adult↗

PubMed2006

Use of variations in staphylococcal interspersed repeat units for molecular typing of methicillin-resistant Staphylococcus aureus strains.

Staphylococcal interspersed repeat unit typing has previously been shown to have the ability to discriminate between epidemic methicillin-resistant Staphylococcus aureus strains in the United Kingdom. The current study illustrates its ability to distinguish between strains within an endemic setting thereby providing a rapid transportable typing method for the identification of transmission events.

Bacterial Typing Techniques↗

PubMed2006

Over-the-head CPR.

Explore the source record for details and available documents.

Cardiopulmonary Resuscitation↗

PubMed2005

The impact of compliance with 6-hour and 24-hour sepsis bundles on hospital mortality in patients with severe sepsis: a prospective observational study.

INTRODUCTION: Compliance with the ventilator care bundle affects the rate of ventilator-associated pneumonia. It was not known, however, whether compliance with sepsis care bundles has an impact on outcome. The aims of the present study were to determine the rate of compliance with 6-hour and 24-hour sepsis bundles and to determine the impact of the compliance on hospital mortality in patients with severe sepsis or septic shock. METHODS: We conducted a prospective observational study on 101 consecutive adult patients with severe sepsis or septic shock on medical or surgical wards, or in accident and emergency areas at two acute National Health Service Trust Teaching hospitals in England. The main outcome measures were: the rate of compliance with 6-hour and 24-hour sepsis care bundles adapted from the Surviving Sepsis Campaign guidelines on patients' clinical care; and the difference in hospital mortality between the compliant and the non-compliant groups. RESULTS: The median age of the patients was 69 years (interquartile range 51 to 78), and 53% were male. The sources of infection were sought and confirmed in 87 of 101 patients. The chest was the most common source (50%), followed by the abdomen (22%). The rate of compliance with the 6-hour sepsis bundle was 52%. Compared with the compliant group, the non-compliant group had a more than twofold increase in hospital mortality (49% versus 23%, relative risk (RR) 2.12 (95% confidence interval (CI) 1.20 to 3.76), P = 0.01) despite similar age and severity of sepsis. Compliance with the 24-hour sepsis bundle was achieved in only 30% of eligible candidates (21/69). Hospital mortality was increased in the non-compliant group from 29% to 50%, with a 76% increase in risk for death, although the difference did not reach statistical significance (RR 1.76 (95% CI 0.84 to 3.64), P = 0.16). CONCLUSION: Non-compliance with the 6-hour sepsis bundle was associated with a more than twofold increase in hospital mortality. Non-compliance with the 24-hour sepsis bundle resulted in a 76% increase in risk for hospital death. All medical staff should practise these relatively simple, easy and cheap bundles within a strict timeframe to improve survival rates in patients with severe sepsis and septic shock.

Aged↗

PubMed2005

The beta-agonist lung injury trial (BALTI): a randomized placebo-controlled clinical trial.

RATIONALE: Experimental data suggest that manipulation of alveolar fluid clearance with beta-agonists can accelerate the resolution of alveolar edema and improve survival. OBJECTIVE: To determine if a sustained infusion of intravenous salbutamol (albuterol) would accelerate the resolution of alveolar edema in adult patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). METHODS: This was a single-center, double-blind, randomized controlled trial. Patients with ALI/ARDS were randomized to treatment with intravenous salbutamol (15 microg kg(-1) h(-1)) or placebo for 7 d. The primary endpoint was extravascular lung water measured by thermodilution (PiCCO) at Day 7. MEASUREMENTS AND MAIN RESULTS: Sixty-six patients were screened; of these, 40 met the inclusion criteria and were enrolled during 2001-2003. Patients in the salbutamol group had significantly lower lung water at Day 7 than the placebo group (9.2 +/- 6 vs. 13.2 +/- 3 ml kg(-1); 95% confidence interval difference, 0.2-8.3 ml kg(-1); p = 0.038). Plateau airway pressure was lower at Day 7 in the salbutamol group (23.9 +/- 3.8 cm H2O) versus placebo (29.5 +/- 7.2 cm H2O; p = 0.049). There was a trend toward lower Murray lung injury score at Day 7 in the salbutamol group (1.7 +/- 0.9) versus placebo (2.0 +/- 0.6; p = 0.2). Patients in the salbutamol group had a higher incidence of supraventricular arrhythmias (26 vs. 10%; p = 0.2). CONCLUSION: Although further research is required to confirm the efficacy and safety of intravenous salbutamol in ALI/ARDS, this trial provides the first proof of principle that, in humans with ALI/ARDS, sustained treatment with intravenous beta-agonists reduces extravascular lung water.

Adrenergic beta-Agonists↗

PubMed2005

[No influence of increased frequency on fatigability of tetanic contraction in rat atrophic soleus].

The present study was performed to observe the time course and features of intermittent tetanic contractile function changes in soleus and extensor digitorum longus (EDL) muscles of tail-suspended rats. The optimal stimulating frequency, fatigability and time-dependent recovery after fatigue were measured in isolated muscle strips. The optimal stimulating frequency of soleus and EDL was 60 Hz and 120 Hz in control rats, respectively. It was not changed in 1-week unloaded soleus, but shifted to 80 Hz and 100 Hz in 2- and 4-week unloaded soleus, respectively. The maximal isometric tension (P(o)) of tetanic contraction at optimal stimulating frequency did not alter in 1- and 2-week unloaded soleus, but significantly decreased in 4-week unloaded soleus. After 5 min of fatigue, tetanic contractile tension of control soleus was decreased to 22.8% P(o), but significantly decreased to 10.4%, 10.0% and 11.6% P(o) in 1-, 2- and 4-week unloaded soleus, respectively. The tetanic contractile tension recovered to 98% P(o) in control soleus at the twentieth minute after fatigue, but only recovered to 79.0%, 83.6% and 78.5% P(o) in 1-, 2- and 4-week unloaded soleus. The optimal stimulating frequency, P(o), fatigability and time-dependent recovery of intermittent tetanic contraction were not altered in unloaded EDL compared with control. These results indicate that higher stimulating frequency can compensate the P(o) reduction in 1- and 2-week unloaded soleus, but not in 4-week unloaded soleus. The unloaded soleus, but not EDL, is more susceptible to fatigue than the synchronous controls. The unloaded soleus not only fatigues to a greater extent but also recovers significantly less than the control.

Animals↗

PubMed2005

Safety and tolerability of nonbronchoscopic lavage in ARDS.

STUDY OBJECTIVE: This study compared the safety profiles of bronchoscopic lavage with nonbronchoscopic lavage in the investigation of patients with acute lung injury (ALI) or ARDS. DESIGN: Single-center, randomized, cross-over study. SETTING: General ICU in the United Kingdom. PARTICIPANTS: Fourteen patients with ALI or ARDS. INTERVENTIONS: Bronchoscopic BAL and nonbronchoscopic BAL 1 h apart. MEASUREMENTS AND RESULTS: Hemodynamic and ventilatory parameters were recorded during and for 1 h following each procedure. On average, bronchoscopic lavage took longer to perform than nonbronchoscopic lavage (7 min and 6 s vs 2 min and 28 s, p < 0.001). During the procedures, bronchoscopic lavage increased heart rate and systolic BP more than nonbronchoscopic lavage (23% vs 10% [p < 0.01] and 18% vs 7% [p < 0.01]). Three patients had ST-segment depression during bronchoscopic, and one patient had ST-segment depression during nonbronchoscopic lavage (p = 0.298). Bronchoscopic lavage reduced minute ventilation by 63 +/- 17.3%, while nonbronchoscopic lavage only reduced it by 36 +/- 21.9% (p < 0.001). Paco(2) rose more after bronchoscopic lavage than after nonbronchoscopic lavage. CONCLUSION: Nonbronchoscopic lavage is associated with less marked physiologic derangements than bronchoscopic lavage. Further studies are required to validate the hypothesis that nonbronchoscopic lavage may be safer in patients with unstable coronary heart disease or head injury/raised intracranial pressure who are at risk from unpredictable fluctuations in hemodynamic and ventilatory profiles.

Aged↗

PubMed2005

[Prevalence of microalbuminuria in type 2 diabetic patients with hypertension].

OBJECTIVE: To investigate the prevalence of microalbuminuria in type 2 diabetic patients with hypertension. METHOD: Urinary albumin excretion was measured in 55 diabetic patients with hypertension by colorimetric methods using commercially available test strips of Nephur 7 and Micro-II, the latter test strips employed only when the former yielded negative results for proteinuria. The height, body weight, waist circumference and blood pressure were measured for all the patients with also biochemical examination for serum total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, blood glucose and creatinine. HbA1c was determined by Bio-STAT. RESULTS: The rates of normal urinary albumin, micro- and macroalbuminuria were 66.67%, 22.22% and 11.11% in these patients, respectively. In patients with a history of diabetes for more than 10 years, the rates were 58.33%, 8.33% and 33.33%, respectively. CONCLUSION: Nearly 1/3 of type 2 diabetic patients with hypertension have microalbuminuria and proteinuria, and screening for microalbuminuria and proper interventions in these patients might prove beneficial.

Albuminuria↗

PubMed2005

[Determination of HLA-A, -B allele polymorphism in the Luoba nationality living in Tibet Autonomous Region in China].

OBJECTIVE: To investigate the HLA-A, -B allele polymorphism in the Luoba ethnic population. METHODS: HLA-A, -B DNA types in 92 healthy individuals of Luoba nationality in the Linzhi area, Tibet Autonomous Region, were investigated by polymerase chain reaction-sequence specific oligo-nucleotide (PCR-SSO). RESULTS: Ten alleles at HLA-A locus, and 19 alleles at HLA-B locus in Luoba ethnic group were detected. Of the 10 HLA-A alleles detected, the three most common alleles were HLA-A*11(allele frequency: 36.40%), -A*02 (25.50%), -A*24 (23.90%), and they covered 85.80% of the total HLA-A alleles detected from the Luoba ethnic group. Of the 19 HLA-B alleles detected, the three most common alleles were HLA-B*40 (27.20%), -B*15 (11.40%) and -B*38(10.90%), and they covered 49.50% of the total -B alleles detected in the Luoba ethnic group. CONCLUSION: The distribution of HLA-A, -B allele polymorphism in the Luoba nationality is distinctive, but some of the gene distribution in the Luoba group is nearer to that in the Tibetan group. These are consistent with the results of ethnological, historical and sociological researches.

Alleles↗

PubMed2005

[Determination of HLA-DRB1 gene polymorphism in Luoba ethnic group of Tibet].

OBJECTIVE: To investigate the frequencies of allele and genotype of HLA-DRB1 gene in Luoba ethnic group. METHODS: HLA-DRB1 genes from 92 individuals of Luoba ethnic group in Tibet Autonomous region were investigated, using PCR-SSO (polymerase chain reaction -sequence specific oligo-nucleotide) genotyping methods. We compared allele frequencies of Luoba population in HLA-DRB1 locus with that of various ethnic groups distributed worldwide, constructed the phylogenetic tree by UPGMA (unweighted pair group method with arithmetic mean), and counted genetic distance by Nei measure. RESULTS: Of the 11 DRB1 alleles detected, the two most common genes were DRBI * 04( gene frequency: 27.20% ) and DRB * 12 (25.50%) , which covered 52.70% of the total alleles detected from Luoba ethnic group. The frequencies of HLA-DRB1 * 14(15.20% ), DRB1 * 15(9.80% ) and DRB1 * 08(8.20% ) were more than 5%. Luoba was unique in the distribution of HLA alleles. The genetic distance between Luoba and Tibetan was closer than that with other population. A dendrogram based on the DRB1 genes by cluster analysis suggested that Luoba ethnic group might cluster with Tibetan firstly, then cluster with other population living in China (except Uygr) , and cluster with Caucasian and Black finally. CONCLUSION: The HLA-DRBI gene frequency of Luoba individuals in Tibet Linzhi had some differences compared with that of other Chinese population. The kindred relation between Luoba and Tibetan was closer than that with other population, which was coincident with the results of ethnology, history and sociology.

China↗

PubMed2005

[Determination of HLA-A, B, and DRB1 gene polymorphism in Monba ethnic group of Xizang Autonomous Region, China].

OBJECTIVE: To investigate the HLA-A, B, DRB1 allele polymorphism in Monba ethnic population of Xizang Autonomous Region. METHODS: HLA-A, B, DRB1, DNA types in 47 unrelated Monba ethnic healthy individuals from the Xizang Autonomous Region of China were analyzed by polymerase chain reaction-based reverse line-strip sequence specific oligonucleotide hybridization. Based on the HLA-DRB1 alleles frequencies of 11 other ethnic groups in China, a molecular phylogenetic tree was constructed by the Neighbor-Joining (NJ) method. RESULTS: Twenty-three alleles were detected for HLA-A, 39 for HLA-B, and 33 for HLA-DRB1. HLA-A*1101, A*2402, A*02011, A*0206, HLA-B*3802, B*4001, B*4002, B*51011, HLA-DRB1*12021, DRB1*0403, DRB1*0701, DRB1*1201 were the most common alleles. The most frequent alleles were HLA-A*1101(0.2128), HLA-B*3802(0.1064), and HLA-DRB1*12021(0.0851). CONCLUSION: The HLA loci are highly polymorphic in Monba population of Xizang Autonomous Region. Compared with other ethnic groups in China, the Monba ethnic group is close to Tibetan ethnic group.

Alleles↗

PubMed2004

Daily short-period gravitation can prevent functional and structural changes in arteries of simulated microgravity rats.

This study was designed to clarify whether simulated microgravity-induced differential adaptational changes in cerebral and hindlimb arteries could be prevented by daily short-period restoration of the normal distribution of transmural pressure across arterial vasculature by either dorsoventral or footward gravitational loading. Tail suspension (Sus) for 28 days was used to simulate cardiovascular deconditioning due to microgravity. Daily standing (STD) for 1, 2, or 4 h, or +45 degrees head-up tilt (HUT) for 2 or 4 h was used to provide short-period dorsoventral or footward gravitational loading as countermeasure. Functional studies showed that Sus alone induced an enhancement and depression in vasoconstrictor responsiveness of basilar and femoral arterial rings, respectively, as previously reported. These differential functional alterations can be prevented by either of the two kinds of daily gravitational loading treatments. Surprisingly, daily STD for as short as 1 h was sufficient to prevent the differential functional changes that might occur due to Sus alone. In morphological studies, the effectiveness of daily 4-h HUT or 1-h STD in preventing the differential remodeling changes in the structure of basilar and anterior tibial arteries induced by Sus alone was examined by histomorphometry. The results showed that both the hypertrophic and atrophic changes that might occur, respectively, in cerebral and hindlimb arteries due to Sus alone were prevented not only by daily HUT for 4 h but also by daily STD even for 1 h. These data indicate that daily gravitational loading by STD for as short as 1 h is sufficient to prevent differential adaptational changes in function and structure of vessels in different anatomic regions induced by a medium-term simulated microgravity.

Adaptation, Physiological↗

PubMed2004

A comparison between over-the-head and standard cardiopulmonary resuscitation.

BACKGROUND: Standard cardiopulmonary resuscitation (CPR) is performed by kneeling adjacent to the side of the casualty. In certain circumstances it may be difficult or impossible to perform CPR in this position, for example in confined spaces such as a narrow corridor, aircraft or train gangway. The aim of this study was to investigate the technique of over-the-head CPR (OTH CPR), where the CPR provider kneels above the casualty and performs chest compressions OTH of the casualty. METHODS: Twenty volunteers were randomised to a cross over trial where they performed standard and OTH CPR at a 7-day interval. Compression and ventilation variables were recorded on the Laerdal Resusci Annie VAM system. RESULTS: Chest compression depth and ventilation volume declined over time (0-3 min P < 0.001). There was no difference in compression rate, depth, duty cycle or ventilation rate, inflation rate and ventilation volume between techniques. Hand position was incorrect more frequently in the standard compared to the OTH group (incorrect compressions 300 versus 76, respectively, P < 0.001) due principally to a greater proportion of low positioned compressions in the standard CPR group. CONCLUSION: OTH CPR appears equally effective as standard CPR with some marginal advantages in correct hand placement. We suggest that in situations where it is not possible to perform standard CPR, OTH CPR may be considered as a suitable alternative.

Analysis of Variance↗

PubMed2004

Over-the-head CPR.

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Cardiopulmonary Resuscitation↗

PubMed2004

[The inhibiting effect of niflumic acid on airway hyperresponsiveness in asthmatic mice].

OBJECTIVE: To evaluate the inhibiting effect of niflumic acid (NFA), an inhibitor of calcium-activated chloride channel (ClCa) on airway epithelium, on the airway hyperresponsiveness in asthmatic mice. METHODS: BALB/c mice were randomly divided into an asthma group (A group), a NFA prevention asthmatic group (B group) and a sham-challenged group (C group). The airway pressure time index (APTI) and the content of ET-1 and NO in bronchoalveolar lavage fluid (BALF) in all groups were measured. With the isolated tracheal rings with integral epithelium or epithelium removed from the asthma group (A(1) group and A(2) group) and the sham-challenged group (C(1) group and C(2) group), the contractile responsiveness of various rings to methacholine (mACh) was examined, and its change was observed when the rings were exposed to NFA beforehand. RESULTS: Compared with A group (1.62 +/- 0.14), the APTI in B group (1.21 +/- 0.07) was reduced remarkably (P < 0.01), and the contents of ET-1 [(103 +/- 9) ng/L] and NO [(48.5 +/- 3.2) micromol/L] in BALF of A group were significantly higher than those in B group, [(53 +/- 5) ng/L, (23.7 +/- 2.5) micromol/L (P < 0.01), respectively]. The ratios of maximum contractility in A(1), A(2), C(1) and C(2) groups were (3.79 +/- 0.44), (2.15 +/- 0.21), (1.26 +/- 0.14) and (2.06 +/- 0.18), respectively. The contractility of A(1) group was highest among all groups (all P < 0.01), but could be effectively decreased by NFA. CONCLUSIONS: By inhibiting the special ClCa on the airway epithelium, NFA can inhibit the production of ET-1 and NO by epithelium and thus exert preventive effect on airway hyperresponsiveness in asthma.

Animals↗

PubMed2004

[Determination of serum highly sensitive C-reactive protein in patients with type 2 diabetes].

OBJECTIVE: To investigate the relationship between serum level of highly sensitive C-reactive protein (hs-CRP) and insulin sensitivity in type 2 diabetic patients. METHODS: Serum hs-CRP level was determined by highly sensitive enzyme-linked immunosorbent assay (ELISA) in 65 patients with type 2 diabetes and 25 normal controls. Plasma glucose, serum insulin, glycosylated hemoglobin (HbA1c), urinary albumin excretion rate (UAER), plasma lipids and lipoprotein were also measured. Moreover, homeostasis model analysis (HOMA) of insulin resistance index (HOMA-IR) and islet secretion index (HOMA-IS) were calculated to estimate the insulin sensitivity and islet function. RESULTS: In the patients with type 2 diabetes, serum hs-CRP was increased, HOMA-IR index and HOMA-IS index were decreased as compared with the normal control subjects (P<0.01). Moreover, serum hs-CRP was significantly higher in poorly controlled diabetic patients (n=23) with HbA1c >7% than that in well controlled diabetic patients (n=42) with HbA1c<7%. Liner regression analysis in diabetic patients showed that serum hs-CRP was negatively correlated with HOMA-IS index but positively correlated with fasting plasma glucose, body mass index, HbA1c and diastolic blood pressure, respectively. CONCLUSION: Serum HS-CRP level is higher in the patients with type 2 diabetes than in normal subjects, and plays an role in the development and progression of type 2 diabetes mellitus.

Adult↗