Effects of the circadian rhythm on milk composition in dairy cows: Does day milk differ from night milk?

Metabolism in most organisms can show variations between the day and night. These variations may also affect the composition of products derived from livestock. The aim of the present study was to investigate the difference in composition between the day milk and night milk of dairy cows. Ten multiparous Holstein cows (milk yield = 25.2 ± 5.00 kg/d) were randomly selected during mid lactation. Milk samples were collected at 0500 h ("night milk") and 1500 h ("day milk") and analyzed to determine their composition. Mid-infrared spectroscopy was used to analyze macronutrient content of milk. Metabolomics and lipidomics were used to detect and analyze small molecules and fatty acids, respectively. An automatic biochemical analyzer and ELISA kits were used to determine biochemical indicators, as well as antioxidant and immune parameters in the milk. Though milk fat, protein, lactose, and total milk solids were not different between day milk and night milk, small molecules, metabolites and lipids, and hormones and cytokines differed between day milk and night milk. Regarding biochemical and immune-related indicators, the concentrations of malondialdehyde, HSP70, and HSP90 in night milk were lower than that in day milk. However, interferon-γ levels were higher in night milk. Additionally, night milk was naturally rich in melatonin. Lipidomics analyses showed that the levels of some lipids in night milk were higher than those in day milk. Metabolomics analyses identified 36 different metabolites between day milk and night milk. Higher concentrations of N-acetyl-d-glucosamine, cis-aconitate, and d-sorbitol were observed in day milk. However, the other 33 metabolites analyzed, including carbohydrates, lipids, AA, and aromatic compounds, showed lower concentrations in day milk than in night milk. The present findings show that the composition of night milk differs considerably from that of day milk. Notable changes in the circadian rhythm also altered milk composition. These results provide evidence to support the strategic use and classification of day milk and night milk.

Coronavirus disease 2019: a bibliometric analysis and review.

OBJECTIVE: On December 8, 2019, many cases of pneumonia with unknown etiology were first reported in Wuhan, China, subsequently identified as a novel coronavirus infection aroused worldwide concern. As the outbreak is ongoing, more and more researchers focused interest on the COVID-19. Therefore, we retrospectively analyzed the publications about COVID-19 to summarize the research hotspots and make a review, to provide reference for researchers in the world. MATERIALS AND METHODS: We conducted a search in PubMed using the keywords "COVID-19" from inception to March 1, 2020. Identified and analyzed the data included title, corresponding author, language, publication time, publication type, research focus. RESULTS: 183 publications published from 2020 January 14 to 2020 February 29 were included in the study. The first corresponding authors of the publications were from 20 different countries. Among them, 78 (42.6%) from the hospital, 64 (35%) from the university and 39 (21.3%) from the research institution. All the publications were published in 80 different journals. Journal of Medical Virology published most of them (n=25). 60 (32.8%) were original research, 29 (15.8%) were review, 20 (10.9%) were short communications. 68 (37.2%) epidemiology, 49 (26.8%) virology and 26 (14.2%) clinical features. CONCLUSIONS: According to our review, China has provided a large number of research data for various research fields, during the outbreak of COVID-19. Most of the findings play an important role in preventing and controlling the epidemic around the world. With research on the COVID-19 still booming, new vaccine and effective medicine for COVID-19 will be expected to come out in the near future with the joint efforts of researchers worldwide.

[Clinical value of diffusion tensor imaging parameter value in evaluating the prognosis of spinal cord injury in acute cervical spinal cord injury].

Objective: To evaluate the clinical application value of diffusion tensor imaging (DTI) parameter in evaluating the prognosis of spinal cord injury in acute cervical spinal cord injury. Method: From October 2012 to December 2015, a total of 23 patients with acute cervical spinal cord injury were examined by routine MRI-T2WI high signal DTI examination, according to the American Spinal Injury Association (ASIA) damage standard. One month later according to the functional outcome of the spinal cord, all patients were divided into non improvement group (group A) 4 cases (2 cases of ASIA-A, 2 cases of grade B) and improvement group (group B) 19 cases (13 cases of ASIA-C, 5 cases of grade D, 1 case of grade B), 15 cases of healthy volunteers as the normal group (group C ). The FA value, ADC and axial eigen value[λ∥=λ1], radial eigen value[λ⊥=(λ2+ λ3)/2]of before and after the treatment in group A and group B were compared by paired t test respectively. Single factor analysis of variance (ANOVA) was used to analyze the differences of DTI among the group A, group B and group C, and LSD test was used to compare the differences among the groups.Before and after treatment, the DTI measurement area was consistent.Changes of nerve fiber bundles in group A and group B before and after treatment were displayed in DTT. Results: After the treatment , the FA value of group A decreased , ADC value and λ⊥ value increased than that of before treatment(t=3.037, -4.183, -4.805, all P<0.05), λ∥ value increased(t=-1.160, P>0.05). After the treatment , the FA value and ADC value of group B increased , λ⊥ value decreased than that of before treatment(t=-3.344, -3.642, 4.694, all P<0.05), λ∥ value increased(t=-0.596, P>0.05). After treatment, there were statistical differences in FA values, λ⊥ value , ADC values and λ∥ values among three groups (F=71.958, 70.432, 75.902, 22.521, all P<0.01). Conclusion: The changes of FA value, λ⊥ value are the two most sensitive indicators of acute cervical spinal cord injury of spinal cord function prognosis.It suggests the poor prognosis of spinal cord function when FA value decreases and λ⊥ value continues to increase.DTT can visually display subtle changes in the nerve fiber bundle.