CT quantification of pulmonary vessels in lung aging

AIM

To evaluate the effect of aging on pulmonary vessels based on computed tomography (CT) quantification and analyse the correlation between quantitative pulmonary vascular volume and pulmonary function during aging.

MATERIALS AND METHODS

A total of 330 healthy adult volunteers, including 161 men (53 aged 20-39 years, 61 aged 40-59 years, and 47 aged ≥60 years) and 169 women (53 aged 20-39 years, 63 aged 40-59 years, and 53 aged ≥60 years) were recruited in this study. AVIEW software was used to quantitatively measure pulmonary vascular volume, including pulmonary total blood vessel volume (TBV) and small blood vessel volume with a cross-sectional area of <5 mm2 (BV5). Pulmonary vascular volume parameters were standardised using the ratio of vascular volume to the body surface area (BSA; TBV/BSA and BV5/BSA). Subsequently, the effect of aging on the pulmonary vessels was analysed.

RESULTS

The pulmonary vascular volume parameters TBV/BSA and BV5/BSA of the whole lung, right lung, and left lung decreased significantly with increasing age (p<0.05). Additionally, TBV/BSA and BV5/BSA of the whole lung were higher in men than in women. The declining trend of pulmonary vascular volume was consistent in men and women and increased with age.

CONCLUSIONS

The pulmonary vascular volume parameters, TBV/BSA and BV5/BSA, decreased with age and were weakly positively correlated with pulmonary function.

Effect of uniconazole and nitrogen level on lodging resistance and yield potential of maize under medium and high plant density

Lodging in maize results in grain yield reduction. This experiment investigated the effects of different application rates of the growth retardant, uniconazole (UCZ), and nitrogen (N) on medium and high maize population densities on lodging resistance and yield. UCZ was applied to maize seeds at concentrations of 0 (U₀ ) and 25 (U₂₅ ) mg kg^-1 , and three different N application rates, 0 (N₀ ), 150 (N₁₅₀ ) and 225 (N₂₂₅ ) kg ha^-1 , at plant densities of 75,000 (D₁ ) and 105,000 plants ha^-1 (D₂ ). UCZ application, different N rates and plant population density affected the lodging resistance and yield attributes of maize. The diameter, plumpness, cortex penetration and bending strengths of the internodes were enhanced with UCZ and N application at medium and high plant density, where maximum values were obtained with U₂₅ N₁₅₀ D₁ . Internode length increased in the high-density population and higher N rate, whereas UCZ reduced internode length, where maximum internode length was obtained with U₀ N₂₂₅ D₂ . Plant height, centre of gravity height, ear and height above ear-bearing node were higher with the high N rate, while UCZ reduced it significantly. UCZ, N rate and plant density enhanced lignin accumulation in the third internode and ear-bearing internode, where maximum values were obtained with U₂₅ N₁₅₀ D₁ . Yield and yield attributes were also improved by UCZ, N rate and population density. Treatment with U₂₅ N₁₅₀ D₂ significantly improved grain yield of maize compared with the other treatments.

Unique genetic profiles from cerebrospinal fluid cell-free DNA in leptomeningeal metastases of EGFR-mutant non-small-cell lung cancer: a new medium of liquid biopsy

Background

Leptomeningeal metastases (LM) are more frequent in non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the purpose of this study was to explore the potential role of cerebrospinal fluid (CSF) as a source of liquid biopsy in patients with LM.

Patients and methods

Primary tumor, CSF, and plasma in NSCLC with LM were tested by next-generation sequencing. In total, 45 patients with suspected LM underwent lumbar puncture, and those with EGFR mutations diagnosed with LM were enrolled.

Results

A total of 28 patients were enrolled in this cohort; CSF and plasma were available in 26 patients, respectively. Driver genes were detected in 100% (26/26), 84.6% (22/26), and 73.1% (19/26) of samples comprising CSF cell-free DNA (cfDNA), CSF precipitates, and plasma, respectively; 92.3% (24/26) of patients had much higher allele fractions in CSF cfDNA than the other two media. Unique genetic profiles were captured in CSF cfDNA compared with those in plasma and primary tissue. Multiple copy number variations (CNVs) were mainly identified in CSF cfDNA, and MET copy number gain identified in 47.8% (11/23) of patients was the most frequent one, while other CNVs included ERBB2, KRAS, ALK, and MYC. Moreover, loss of heterozygosity (LOH) of TP53 was identified in 73.1% (19/26) CSF cfDNA, which was much higher than that in plasma (2/26, 7.7%; P < 0.001). There was a trend towards a higher frequency of concomitant resistance mutations in patients with TP53 LOH than those without (70.6% versus 33.3%; P = 0.162). EGFR T790M was identified in CSF cfDNA of 30.4% (7/23) of patients who experienced TKI progression.

Conclusion

CSF cfDNA could reveal the unique genetic profiles of LM and should be considered as the most representative liquid biopsy medium for LM in EGFR-mutant NSCLC.

Investigating seed dormancy in cotton (Gossypium hirsutum L.): understanding the physiological changes in embryo during after-ripening and germination

The dormancy of seeds of upland cotton can be broken during dry after-ripening, but the mechanism of its dormancy release remains unclear. Freshly harvested cotton seeds were subjected to after-ripening for 180 days. Cotton seeds from different days of after-ripening (DAR) were sampled for dynamic physiological determination and germination tests. The intact seeds and isolated embryos were germinated to assess effects of the seed coat on embryo germination. Content of H₂ O₂ and phytohormones and activities of antioxidant enzymes and glucose-6-phosphate dehydrogenase were measured during after-ripening and germination. Germination of intact seeds increased from 7% upon harvest to 96% at 30 DAR, while embryo germination improved from an initial rate of 82% to 100% after 14 DAR. Based on T₅₀ (time when 50% of seeds germinate) and germination index, the intact seed and isolated embryo needed 30 and 21 DAR, respectively, to acquire relatively stable germination. The content of H₂ O₂ increased during after-ripening and continued to increase within the first few hours of imbibition, along with a decrease in abscisic acid (ABA) content. A noticeable increase was observed in gibberellic acid content during germination when ABA content decreased to a lower level. Coat removal treatment accelerated embryo absorption of water, which further improved the accumulation of H₂ O₂ and changed peroxidase content during germination. For cotton seed, the alleviation of coat-imposed dormancy required 30 days of after-ripening, accompanied by rapid dormancy release (within 21 DAR) in naked embryos. H₂ O₂ acted as a core link between the response to environmental changes and induction of other physiological changes for breaking seed dormancy.

[Effects and mechanisms of Notch signaling pathway on immune imbalance in chronic obstructive pulmonary disease]

Objective: To explore the role of Notch signaling pathway on immune imbalance in chronic obstructive pulmonary disease (COPD). Methods: Thirty BALB/c mice were randomly assigned into the healthy control group, COPD group, and COPD Gamma secretase inhibitors (GSI) group. Cigarette smoke exposure was used to establish the COPD model. T cells were enriched by filtering through nylon wool columns. The proportion of spleen-derived T-lymphocyte subsets was detected by flow cytometry. Real-time quantitative polymerase chain reaction (RT-PCR) and Western blot (WB) were used to detect the expression of splenic T cells' Notch1 and its downstream Hes1 mRNA and protein respectively. Results: The percentage of Th1, Th17 and Treg cells in CD₄^＋T cells of COPD mice (13.20±0.95, 10.22±0.45, 0.41±0.09)% were significantly increased compared with the healthy control group (8.07±0.44, 5.98±0.26, 0.26±0.05)%(all P<0.01). The proportion of Th1 and Th17 cells in COPD GSI group mice (9.48 ± 0.66, 7.70 ±0.39)% were significantly reduced compared with COPD group (all P<0.01). Ratio of Th1/Th2 in COPD group (18.70±4.12) was significantly increased compared with the healthy control group (12.63±1.91) (P<0.01), the percentage of Th17 and Treg in CD₄^＋ T cell increased 71% and 58% respectively. GSI decreased the ratios of Th1/Th2 and Th17/Treg (all P<0.01). Notch1 receptor and its downstream Hes1 mRNA expression (5.15±0.77, 1.92±0.32) and protein expression (0.85±0.04, 0.16±0.02) of COPD mice were significantly increased compared with the healthy group respectively [(1.00 ± 0.00, 1.00 ± 0.00) and (0.17±0.01, 0.09±0.01)] (all P<0.01). GSI significantly inhibited the expression of mRNA and protein in Notch1 and its downstream Hes1 (all P<0.01). Notch1 and Hes1 mRNA and protein expressions were correlated positively with Th1 and Th17 cells and negatively correlated with Th2 and Treg cells in COPD group(all P<0.05). Conclusion: In COPD mice, there was T-lymphocyte subsets imbalance, such as the increased of Th1, Th17 proinflammatory cells, Notch1 and its downstream Hes1 mRNA and protein levels were increased, and was associated with T-lymphocyte subsets imbalance. GSI could partially inhibit Notch1, Hes1 expression and Th1 and Th17 cells, and thus Notch signaling pathway was involved in the immune disorder of COPD mice.

A phase III randomised controlled trial of erlotinib vs gefitinib in advanced non-small cell lung cancer with EGFR mutations

Background:

A phase III trial was conducted to compare the safety and efficacy of erlotinib with that of gefitinib in advanced non-small cell lung cancer harbouring epidermal growth factor receptor mutations in exon 19 or 21.

Methods:

Eligible patients were randomised to receive erlotinib (150 mg per day) or gefitinib (250 mg per day) orally until disease progression or unacceptable toxicity. We aimed to determine whether erlotinib is superior to gefitinib in efficacy. The primary end point was progression-free survival.

Results:

A total of 256 patients were randomised to receive erlotinib (N=128) or gefitinib (N=128). Median progression-free survival was not better with erlotinib than with gefitinib (13.0 vs 10.4 months, 95% confidence interval (CI) 0.62–1.05, P=0.108). The corresponding response rates and median overall survival were 56.3% vs 52.3% (P=0.530) and 22.9 vs 20.1 months (95% CI 0.63–1.13, P=0.250), respectively. There were no significant differences in grade 3/4 toxicities between the two arms (P=0.172).

Conclusions:

The primary end point was not met. Erlotinib was not significantly superior to gefitinib in terms of efficacy in advanced non-small cell lung cancer with epidermal growth factor receptor mutations in exon 19 or 21, and the two treatments had similar toxicities.

Stability of nano-sized titanium dioxide in an aqueous environment: effects of pH, dissolved organic matter and divalent cations

Nano-sized titanium dioxide in the aquatic environment has a potential impact on the environment and human health. In this study, the impact of pH value, dissolved organic matter (DOM) and divalent cations (Ca(2+)) on the stability of titanium dioxide nanoparticles (nano-TiO2) in an aqueous environment was investigated in batch tests. The results showed that the particle size of nano-TiO2 was not sensitive to pH value but was inversely proportional to zeta potential. The nano-TiO2 becomes more stable with surface zeta potential, accompanied by small particle size and high dispersion. In the presence of DOM, the particle size was smaller and the stability of nano-TiO2 could be enhanced. This might be a synergistic effect of the ligand exchange and electrostatic force. Particle size increased with the addition of Ca(2+) and the stability decreased.

Capsaicin for allergic rhinitis in adults

BACKGROUND

Allergic rhinitis represents a global health problem. Non-specific nasal hyperresponsiveness is an important feature of allergic and non-allergic rhinitis. This phenomenon is believed to result from the effect of allergic inflammation on the sensory nerves that supply the upper airway mucosa. A pharmacologic agent that has proved useful in the investigation of effects of neuronal stimulation is capsaicin, the pungent component of hot pepper. Intranasal capsaicin specifically stimulates afferent nerves consisting mostly of unmyelinated C fibers and some myelinated A-delta fibers. As a result it can trigger central and axonal reflexes, the latter being putatively mediated by the release of neuropeptides. Capsaicin as a blocking agent of neuropeptides, blocks the axon reflex and may exert a curative effect on allergic rhinitis.

OBJECTIVES

To assess the effectiveness of capsaicin for allergic rhinitis in adults.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to 2006) and EMBASE (1974 to 2006). We assessed bibliographies from included studies, and contacted authors of known studies for additional information about published and unpublished trials. The date of the most recent search was January 2006.

SELECTION CRITERIA

Randomised controlled trials of capsaicin for allergic rhinitis in adults were included.

DATA COLLECTION AND ANALYSIS

Three reviewers read each paper, blind to its identity. Decisions concerning inclusion were made by simple majority. We all performed quality assessment independently.

MAIN RESULTS

One small trial did not find evidence that intranasal capsaicin had a therapeutic effect in allergic rhinitis. A small pharmacological effect on clinical histamine dose response was found. After treatment, leukotriene levels in nasal lavage did not increase in the capsaicin group.

AUTHORS' CONCLUSIONS

There is insufficient evidence to assess the use of capsaicin in clinical practice.