Analysis of breath acetone has been used as a diagnostic tool for diabetes. Due to its nature of volatility and activity, it is very difficult to accurately measure the concentration of acetone in human breath by gas chromatography-mass spectrometry (GC-MS). To overcome this problem, we developed a new method using GC-MS and solid-phase microextraction (SPME) with on-fiber derivatization to determine acetone in human breath. Breath gas from controls and diabetic patients was collected in 3-l Tedlar bags. O-2,3,4,5,6-(Pentafluorobenzyl) hydroxylamine hydrochloride (PFBHA) in solution was firstly adsorbed on the SPME fiber of 65 microm polydimethylsiloxane-divinylbenzene (PDMS-DVB), and then the fiber was further headspace exposed in exhaled gas in the Tedlar bag at 40 degrees C for 4 min. Finally, the formed acetone oxime on the fiber was desorbed and analyzed by GC-MS. Using external standard method, acetone in the human breath was quantitatively analyzed by measurement of its oxime. The method provided a low detection limit of 0.049 ppbv for acetone in breath, relative standard deviation (R.S.D.) value of 3.4%, excellent accuracy. In addition, the method required simple sample preparation and no organic solvent. Acetone in diabetic breath was found to be higher than 1.71 ppmv, while its concentration in normal breath was lower than 0.76 ppmv. The results show that GC-MS and SPME with on-fiber derivatization is a simple, rapid and sensitive and solvent-free method for determination of low concentration acetone in breath and analysis of breath acetone can be used as supplementary tool for diagnosis of diabetes.

ObjectivesPeptest is a new non‐invasive reflux diagnostic test based on lateral flow technology that containing two highly specific human pepsin monoclonal antibodies for detecting pepsin, a biomarker for reflux disease. The primary aim of this multicenter clinical study was to validate the efficacy of Peptest in patients diagnosed with gastroesophageal reflux and healthy controls in China.MethodsPatients with suspected gastroesophageal reflux underwent an endoscopy and were classified into non‐erosive reflux disease and erosive esophagitis subgroups. A healthy control group was also recruited. All participants were given a reflux disease questionnaire—patients scoring greater than 12 and controls scoring zero. All participants provided a postprandial saliva sample and most patients gave an additional post‐symptom sample for pepsin analysis.ResultsAltogether 1032 participants aged between 19 and 78 years were recruited. They consisted of 488 patients with non‐erosive reflux disease, 221 with erosive esophagitis and 323 healthy controls. The number of postprandial and post‐symptom samples analyzed totaled 1031 and 692, respectively. The results across all centers showed an overall pepsin‐positive sensitivity of 85%, a specificity of 60%, a positive predictive value of 82%, a negative predictive value of 65% and a positive likelihood ratio of 2.12.ConclusionThe sensitivity of Peptest was high, but the specificity achieved in some centers was low, resulting overall in only a moderate specificity. Further diagnostic investigative studies are warranted.

This study aimed to investigate risk factors associated with breast cancer among Han Chinese women in northern and eastern China. A matched case-control study involving 1489 patients with breast cancer and 1489 controls was conducted across 21 hospitals in 11 provinces in China, from April 2012 to April 2013. We developed a structured questionnaire to record information from face-to-face interviews with participants. Student’s t-tests, Pearson’s chi-square tests, and univariate and multivariate conditional logistic regression analyses were used to identify variables with significant differences between the case and control groups. Ten variables were identified (P<0.05): location, economic status, waist-to-hip ratio, menopause, family history of breast cancer, present life satisfaction, sleep satisfaction, milk products, behavior prevention scores, and awareness of breast cancer. We identified a comprehensive range of factors related to breast cancer, among which several manageable factors may contribute to breast cancer prevention. Further prospective studies concerning psychological interventions, sleep regulation, health guidance, and physical exercise are required. A screening model for high-risk populations should be put on the agenda.

The apolipoprotein E ε4 (APOE ε4) allele is a well-established genetic risk factor for Alzheimer's disease (AD). Numerous studies have suggested that the modulation of APOE ε4 affects cognition and brain structure and function in healthy populations, particularly in the hippocampus, a key area associated with AD pathology. However, the effect of APOE ε4 allele on cognitive performance, hippocampal structural morphology, and specifically on functional characteristics in patients with AD remains poorly understood. Here, we employed a neuropsychological battery test and multi-modal structural MRI and resting-state functional MRI dataset to systematically investigate cognitive performance, hippocampal structural volume, and functional properties (including local low-frequency oscillating amplitude, intra-regional functional synchrony, and inter-regional functional connectivity) in 16 APOE ε4-carriers and 26 non-carriers at early stages of AD. Compared to non-carriers, APOE ε4-carriers exhibited poorer performance on recognition performance, but performed better on the late item generation of the verbal fluency task (associated with executive function). Structural imaging analysis revealed that APOE ε4-carriers exhibited smaller left hippocampal volumes compared to non-carriers, and the result remains significant after correcting for effects of brain size. Functional imaging analysis revealed that APOE ε4-carriers exhibited decreased amplitude of low-frequency fluctuations in the left hippocampus, non-significant changes in intra-regional synchronization within the hippocampus and decreased hippocampal functional connectivity predominantly in components of the default-mode network including the medial frontal and parietal cortices and the lateral temporal cortical regions. Taken together, our results showed APOE genotypic effects on the cognitive profile and hippocampal structural and functional characteristics in patients at early stages of AD, thus providing empirical evidence for the modulation of the APOE genotype on disease phenotype.