MetaMOPE: a web service for mobile phase determination and fast chromatography peaks evaluation for metabolomics

Motivation

Liquid chromatography coupled with mass spectrometry (LC-MS) is widely used in metabolomics studies, while HILIC LC-MS is particularly suited for polar metabolites. Determining an optimized mobile phase and developing a proper liquid chromatography method tend to be laborious, time-consuming and empirical.

Results

We developed a containerized web tool providing a workflow to quickly determine the optimized mobile phase by batch-evaluating chromatography peaks for metabolomics LC-MS studies. A mass chromatographic quality value, an asymmetric factor, and the local maximum intensity of the extracted ion chromatogram were calculated to determine the number of peaks and peak retention time. The optimal mobile phase can be quickly determined by selecting the mobile phase that produces the largest number of resolved peaks. Moreover, the workflow enables one to automatically process the repeats by evaluating chromatography peaks and determining the retention time of large standards. This workflow was validated with 20 chemical standards and successfully constructed a reference library of 571 metabolites for the HILIC LC-MS platform.

Availability and implementation

MetaMOPE is freely available at https://metamope.cmdm.tw. Source code and installation instructions are available on GitHub: https://github.com/CMDM-Lab/MetaMOPE.

Supplementary information

Supplementary data are available at Bioinformatics Advances online.

Impact of spiritual and religious activity on quality of sleep in hemodialysis patients

BACKGROUND

Sleep disorders are common in hemodialysis (HD) patients. This study examined the relationship between quality of sleep (QoS) and religious/spiritual activity in HD patients.

METHODS

The study subjects were 861 HD patients from 14 dialysis clinics in Taiwan. QoS and religious/spiritual activity were evaluated by the Pittsburgh Sleep Quality Index (PSQI) questionnaire and the Royal Free Questionnaire respectively.

RESULTS

There was no difference in clinical parameters between the good and poor sleepers. Although total scores of religious and spiritual activity did not correlate with global PSQI score, patients who held strong 'spiritual' beliefs reported more problems in 'sleep disturbances', while those who exercised religious beliefs more strongly reported less trouble in 'daytime dysfunction'.

CONCLUSION

There is no significant correlation between QoS and religious/spiritual activity globally. However, the spiritual and religious activity did associate with different components of QoS.

Ethnicity and renal disease

BACKGROUND

Sexual function is one aspect of physical functioning. Sexual dysfunction, no matter the etiology, could cause distress. In female hemodialysis patients, sexual problems have often been neglected in clinical performance and research.

METHODS

We conducted this study by use of self-reported questionnaires. A total of 578 female hemodialysis patients in northern Taiwan were included in this study. Demographic data, comorbid diseases, medications in use, biochemical, and hematologic parameters were analyzed. All patients were asked to complete by themselves three questionnaires: (1) the Index of Female Sexual Function (IFSF) to assess sexual function; (2) the Beck Depression Inventory (BDI) (Chinese version) to rate the severity of depressive symptoms; and (3) the 36-item Short Form Health Survey Questionnaire (SF-36, Taiwan Standard Version 1.0) to survey their quality of life.

RESULTS

A total of 138 female patients were enrolled into further analysis. The mean age was 48.7 +/- 11.2 years old. The mean IFSF score was 24.5 +/- 9.3. Age, BDI score, and serum triglyceride levels were the independent factors of dysfunction in each sexual functional dimension. Patients with higher IFSF scores had significantly higher scores in physical functioning and mental health (P= 0.007 and 0.018, respectively). Patients with higher intercourse satisfaction had significantly higher general health scores (P= 0.001).

CONCLUSION

Sexual dysfunction is frequent in the female hemodialysis population. It is strongly associated with increasing age, dyslipidemia, and depression. The subjects with sexual dysfunction had poorer quality of life. The diagnosis and treatment of sexual dysfunction should be included in the clinical assessment.

Esophageal varices as a rare complication of central venous dialysis tunneled cuffed catheter

Long-term complications of tunneled cuffed catheters include infection and catheter and venous thrombosis. We present a case of a central venous dialysis tunneled cuffed catheter complicated with esophageal varices resulting from superior vena cava obstruction.

Impact of religious activity on depression and quality of life of chronic peritoneal dialysis patients in Taiwan

BACKGROUND AND PURPOSE

Few studies have reported the impact of psychosocial aspects on quality of life (QOL) in peritoneal dialysis (PD) patients. People in Taiwan enjoy freedom of religious beliefs. We evaluated the possible role of religious activity on depression and QOL in PD patients.

METHODS

Eighty six patients (29 males, 57 females; mean age, 48.3 years) receiving regular PD at National Taiwan University Hospital or Taipei Municipal Jen-Ai Hospital were asked to complete the 10-Question Survey assessing religious activity, the Beck Depression Inventory (BDI) rating severity of depression, and the 36-item Short Form Health Survey Questionnaire (Taiwan Standard Version 1.0) measuring QOL. Patients were categorized into 4 groups according to their religious status, namely: no religious faith; and low, medium, and high religious activity.

RESULTS

For patients professing a religious faith, lower religious activity was correlated with lower QOL and higher BDI scores. These findings persisted after adjusting for possible confounding roles of gender, age, marital status, education, social activity, time on dialysis, and number of comorbid conditions. For patients having no religious faith, QOL as well as BDI scores were comparable with those of patients having high religious activity.

CONCLUSIONS

These results suggest that there may be a benefit to a moderate level of religious activity in chronic PD patients in Taiwan, and that such activity is associated with higher QOL and lower BDI scores.

Diagnostic value of plasma aldosterone/potassium ratio in hypoaldosteronism

The diagnosis of hypoaldosteronism usually depends upon a combination of abnormal clinical and laboratory findings. The most common abnormality in hypoaldosteronism is hyperkalemia, which may be combined with sodium depletion. In the present study, 5 of 16 patients diagnosed with isolated hypoaldosteronism (IHA) had sodium depletion due to renal salt wasting, and four patients had normokalemia. Of these 16 IHA patients, 70% had subnormal baseline and stimulated plasma renin activity (PRA). Six patients diagnosed with type I pseudohypoaldosteronism (PHA) had normal or high PRA and plasma aldosterone concentrations (PAC). In 11 control subjects, supine PAC correlated positively with serum potassium (SK), and PAC stimulated by furosemide and ambulation correlated with the 24-hour urinary potassium excretion (UK). However, these correlations were not found in IHA and PHA patients. The ratio of UK/UNa+K and UNa/UK correlated with the stimulated PAC when the IHA and control subjects were taken as a whole. However, these electrolyte excretion parameters bore no relationship to the supine PAC. The stimulated PAC/SK ratio was used to discriminate the three groups; all IHA patients had a ratio below 3. The results indicate that stimulated PAC reflects the bioactivity of aldosterone on the collecting tubule, and the stimulated PAC/SK ratio is useful for the diagnosis of hypoaldosteronism and pseudohypoaldosteronism.

Acute muscular paralysis in an adult with subclinical Bartter's syndrome associated with gentamicin administration

We report an adult case of asymptomatic Bartter's syndrome with the first presentation of hypokalemic paralysis triggered by gentamicin injection. Marked hypokalemia and hypomagnesemia associated with excessive kaliuresis and magnesiuria were found. Plasma renin activity and aldosterone concentration were high, but blood pressure was normal. Renal biopsy revealed hypercellularity of the renin-producing cell of the juxtaglomerular apparatus. Muscular paralysis subsided after potassium chloride supplementation. Hypokalemia was corrected with potassium and magnesium supplements and the use of diclofenac. To the best of our knowledge, there have been no reports of muscular paralysis associated with gentamicin in Bartter's syndrome.