[Characteristics and risk factors of functional constipation in children aged 0-4 years in Xi 'an]

Objective: To investigate the epidemiology, characteristics and risk factors of functional constipation (FC) in children aged 0-4 years in Xi'an. Methods: From October, 2020 to June, 2021, a prevalence survey was conducted among 2 615 children aged 0-4 years in Xi'an by group sampling. The related factors of FC were investigated by questionnaire designed based on Rome Ⅳ diagnostic criteria.The children were divided into FC group and non-FC group. The prevalence, symptoms and signs of FC were analyzed, and its risk factors were analyzed by multivariate Logistic regression. Results: A total of 2 985 valid questionnaires were handed out, and 2 711 (90.8%) were received back. A total of 2 615 questionnaires were valid, with an effective rate of 96.5%. There were 1 338 males (51.2%) and 1 277 females (48.8%). There were 260 cases in FC group and 2 355 cases in non-FC group. The prevalence of FC in children aged 0-4 years in Xi 'an was 10.6%.There were significant differences in FC prevalence among children of different ages and sex (χ²=14.58,4.39, both P<0.05), but not in urban or rural residence (χ²=3.29, P=0.070). The main symptoms of FC group in the last month were large-diameter feces (73.5%, 191/260), painful defecation or dry and hard defecation (65.8%, 171/260). In the last month, FC group had higher incidences of the Bristol type 1, 2 and 3 stool, fecal retention, prolonged defecation, abdominal pain and incomplete defecation compared with non-FC group, with statistical significance (all P<0.05). Parental history of childhood constipation (OR=2.13, 95%CI 1.55-2.92), fever in the last month (OR=1.86, 95%CI 1.32-2.63), history of constipation (OR=3.24, 95%CI 2.46-4.26) and taking probiotics in the last month (OR=1.45, 95%CI 1.11-1.91) were risk factors of FC in children aged 0-4 years. Stratified with age, the results showed that complementary feeding earlier than 5 months of age or later than 6 months of age (OR=2.42, 95%CI 1.13-5.20), dry stools during the complementary feeding (OR=11.27, 95%CI 5.15-24.66), history of constipation (OR=2.29, 95%CI 1.23-4.29) and taking probiotics in the last month (OR=1.88, 95%CI 1.10-3.23) were risk factors of FC in children aged 0-<1 year, and breastfeeding (OR=0.53, 95%CI 0.29-0.94) was a protective factor of FC in children aged 0-<1 year. Family members' recent constipation history (OR=2.02, 95%CI 1.06-3.85) and past history of constipation (OR=3.06, 95%CI 1.74-5.38) were FC risk factors for children aged 1-<2 years. Parental history of childhood constipation (OR=3.12, 95%CI 2.00-4.85), frequency of eating vegetables less than 3 times per week (OR=3.28, 95%CI 2.00-5.38), history of constipation (OR=3.66, 95%CI 2.42-5.53) and taking antibiotics in the last month (OR=1.65, 95%CI 1.06-2.55) were risk factors for FC in children aged 2-4 years. Conclusions: FC in children aged 0-4 years in Xi'an is mainly manifested with large-diameter feces and painful defecation or dry and hard defecation in the last month. It is associated with a variety of risk factors, which are different in different age groups.

[A clinical and pathological report of delayed encephalopathy after heat stroke]

Objective: To explore the clinical manifestations, dynamic neuroimaging changes and brain histopathologic characteristics of a patient with delayed encephalopathy after heat stroke. Methods: In October 2019, the clinical manifestations, electroencephalogram, cerebrospinal fluid, imaging changes and brain histopathological characteristics of a patient with brain damage caused by heat stroke were retrospectively analyzed. Results: The patient was a 40-year-old male who suddenly appeared dizziness, unconscious, high fever when working in the high temperature environment. The EEG showed diffuse slow wave activity. Early CT was normal, and abnormal signals gradually appeared in the basal ganglia region of the thalamus after a few days. In the late, the MRI found a large area of abnormal signals under the cerebral cortex, and white matter was involved. Pathological examination of brain biopsy showed that cortical neuron loss, loose white matter changes, and significant demyelination changes, while no inflammatory cell infiltration was observed in subarachnoid space, meninges, and dermal white matter. Conclusion: Imaging examination dynamic changes of the delayed encephalopathy is important in the heat stroke, and the main pathological manifestation is demyelination.

[Clinical application of the gasless unilateral axillary approach in endoscopic thyroid surgery]

Objective: To investigate the efficacy, safety and advantages of gasless unilateral axillary approach (GUAA) in endoscopic thyroid surgery. Methods: A total of 334 patients who underwent the GUAA endoscopic thyroid surgery (GUAA group) or conventional open thyroid surgery (OS group) in the Department of Head and Neck Surgery of Zhejiang Cancer Hospital from January 2017 to June 2018 were retrospectively analyzed. There were 45 males and 289 females, aged from 12 to 72 years old, of whom 139 patients were assigned to GUAA group and 195 patients to OS group. Pathological results included papillary thyroid carcinoma (282 cases), nodular goiter (41 cases) and thyroid adenoma (11 cases). Surgical exploration development curve of GUAA group was drawn and was divided into two parts: the technical exploration stage and the technical stable stage. Surgical efficiency, incidences of complications, and incision satisfaction were compared between GUAA group in technical stable stage and OS group. SPSS 25.0 software was adopted for statistical analysis. Results: The mean age in GUAA group was younger than that in OS group, with a significant difference [(35.3±9.5) years vs. (48.1±10.6) years, t=11.31, P<0.01]. The cases in the endoscope group were divided into technical exploration stage for 51 cases and technical stable stage for 88 cases according to the exploration and development curve. In unilateral radical thyroidectomy and unilateral thyroid lobectomy, the mean operation time [(90.6±18.6) min and (93.5±22.0) min] and postoperative drainage volumes [(121.5±87.6) ml and (155.5±69.1) ml] of GUAA group in the stable stage were more than those of OS group [(61.6±15.6) min and (46.5±8.4) min] and [(93.2±42.3) ml and (78.9±48.7) ml]. The difference was statistically significant (t=12.28, 7.23, 3.35 and 3.05 respectively, all P<0.05), but there were no significant differences in surgical bleeding volumes between two groups [(12.7±6.8) ml vs. (13.5±7.7) ml, t=0.74, P>0.05 and (16.3±14.1) ml vs. (11.9±5.1) ml, t=1.05, P>0.05]. Compared with OS group, GUAA group had the lower incidence of anterior cervical discomfort during swallowing (2.3% vs. 29.2%, P<0.01) and the higher incision satisfaction score (1.1±0.5 vs. 2.8±0.7, t=21.12, P<0.01), however, GUAA group had the higher incidence of supraclavicular (or infraclavicular) numbness after surgery (5.7% vs. 0, P<0.01). And there was no significant difference in the incidences of temporary recurrent laryngeal nerve injury, bleeding, hematoma, infection, lymphatic leakage or chylous leakage after surgery between two groups (P>0.05). Conclusion: GUAA endoscopic thyroid surgery is a safe method with high cosmetic satisfaction.

[Clinical analysis of chronic sternal osteomyelitis with sinus tract after cardiovascular surgery]

Objective: To explore the diagnosis, therapy and prevention method of chronic sternal osteomyelitis with sinus tract after cardiovascular surgery. Methods: A total of 53 patients with chronic sternal sinus tract after cardiovascular surgery between January 2000 and January 2016. After definite diagnosis by contrast fistulography and CT scanning, all the patients received combined modality therapy including debridement, musculocutaneous flap transplantation and intermediate thickness free skin graft transplantation if necessary. Results: One patient died of false aneurysm due to the sternal sinus tract infection, there were no peri-operative death for all the left 52 patients. Forty-five patients had primary healing and 7 patients had secondary healing. All the patients became total recovery within 3-12 weeks after operation and maintained well during the 5-18 months' follow-up. Conclusions: For the patients with chronic sternal osteomyelitis, operative therapy should be performed as soon as possible once the diagnosis is confirmed. Combined modality therapy including debridement, musculocutaneous flap transplantation and intermediate thickness free skin graft transplantation is confirmed to be effective and secure.

Genetic diversity of mtDNA D-loop sequences in four native Chinese chicken breeds

1. To explore the genetic diversity of Chinese indigenous chicken breeds, a 585 bp fragment of the mitochondrial DNA (mtDNA) region was sequenced in 102 birds from the Xichuan black-bone chicken, Yunyang black-bone chicken and Lushi chicken. In addition, 30 mtDNA D-loop sequences of Silkie fowls were downloaded from NCBI. The mtDNA D-loop sequence polymorphism and maternal origin of 4 chicken breeds were analysed in this study. 2. The results showed that a total of 33 mutation sites and 28 haplotypes were detected in the 4 chicken breeds. The haplotype diversity and nucleotide diversity of these 4 native breeds were 0.916 ± 0.014 and 0.012 ± 0.002, respectively. Three clusters were formed in 4 Chinese native chickens and 12 reference breeds. Both the Xichuan black-bone chicken and Yunyang black-bone chicken were grouped into one cluster. Four haplogroups (A, B, C and E) emerged in the median-joining network in these breeds. 3. It was concluded that these 4 Chinese chicken breeds had high genetic diversity. The phylogenetic tree and median network profiles showed that Chinese native chickens and its neighbouring countries had at least two maternal origins, one from Yunnan, China and another from Southeast Asia or its surrounding area.

Photo-induced processes in collagen-hypericin system revealed by fluorescence spectroscopy and multiphoton microscopy

Collagen is the main structural protein and the key determinant of mechanical and functional properties of tissues and organs. Proper balance between synthesis and degradation of collagen molecules is critical for maintaining normal physiological functions. In addition, collagen influences tumor development and drug delivery, which makes it a potential cancer therapy target. Using second harmonic generation, two-photon excited fluorescence microscopy, and spectrofluorimetry, we show that the natural pigment hypericin induces photosensitized destruction of collagen-based tissues. We demonstrate that hypericin-mediated processes in collagen fibers are irreversible and may be used for the treatment of cancer and collagen-related disorders.

Tuning the metal-insulator transition in manganite films through surface exchange coupling with magnetic nanodots

In strongly correlated electronic systems, the global transport behavior depends sensitively on spin ordering. We show that spin ordering in manganites can be controlled by depositing isolated ferromagnetic nanodots at the surface. The exchange field at the interface is tunable with nanodot density and makes it possible to overcome dimensionality and strain effects in frustrated systems to greatly increasing the metal-insulator transition and magnetoresistance. These findings indicate that electronic phase separation can be controlled by the presence of magnetic nanodots.

Anisotropy and Corotation of Galactic Cosmic Rays

The intensity of Galactic cosmic rays is nearly isotropic because of the influence of magnetic fields in the Milky Way. Here, we present two-dimensional high-precision anisotropy measurement for energies from a few to several hundred teraelectronvolts (TeV), using the large data sample of the Tibet Air Shower Arrays. Besides revealing finer details of the known anisotropies, a new component of Galactic cosmic ray anisotropy in sidereal time is uncovered around the Cygnus region direction. For cosmic-ray energies up to a few hundred TeV, all components of anisotropies fade away, showing a corotation of Galactic cosmic rays with the local Galactic magnetic environment. These results have broad implications for a comprehensive understanding of cosmic rays, supernovae, magnetic fields, and heliospheric and Galactic dynamic environments.

Observation by an air-shower array in Tibet of the multi-TeV cosmic-ray anisotropy due to terrestrial orbital motion around the Sun

We report on the solar diurnal variation of the galactic cosmic-ray intensity observed by the Tibet III air shower array during the period from 1999 to 2003. In the higher-energy event samples (12 and 6.2 TeV), the variations are fairly consistent with the Compton-Getting anisotropy due to the terrestrial orbital motion around the Sun, while the variation in the lower-energy event sample (4.0 TeV) is inconsistent with this anisotropy. This suggests an additional anisotropy superposed at the multi-TeV energies, e.g., the solar modulation effect. This is the highest-precision measurement of the Compton-Getting anisotropy ever made.

Observation of Multi-TeV Gamma Rays from the Crab Nebula using the Tibet Air Shower Array

The Tibet experiment, operating at Yangbajing (4300 m above sea level), is the lowest energy air shower array, and the new high-density array constructed in 1996 is sensitive to gamma-ray air showers at energies as low as 3 TeV. With this new array, the Crab Nebula was observed in multi-TeV gamma-rays and a signal was detected at the 5.5 sigma level. We also obtained the energy spectrum of gamma-rays in the energy region above 3 TeV which partially overlaps those observed with imaging atmospheric Cerenkov telescopes. The Crab spectrum observed in this energy region can be represented by the power-law fit dJ&parl0;E&parr0;&solm0;dE=&parl0;4.61+/-0.90&parr0;x10-12&parl0;E&solm0;3 TeV&parr0;-2.62+/-0.17 cm-2 s-1 TeV-1. This is the first observation of gamma-ray signals from point sources with a conventional air shower array using scintillation detectors.

[The study of the relationship between diet and primary liver cancer]

Two dietary surveys were carried out in a high prevalence area of primary liver cancer (PLC) and a low PLC area in the Guangxi Zhuang Autonomous Region of China in 1987 and 1988 respectively. The results of these two surveys were similar and no statistical significant differences were observed. They showed that negative correlations between the mortality rates of PLC and the intake amount of rice, fruit, vegetable, energy, protein, crude fiber and ascorbic acid existed. However, between the mortality rates of PLC and the intake of corn, and peanut oil, positive correlations were noted. The aflatoxin content of corn, peanut and peanut oil was greater than that of rice, hence the possible relationship between aflatoxin and PLC. It suggested that diet and nutrients could affect PLC mortality rates.

[Gas chromatography with electron capture detector for determining DON and NIV in scabby wheat]

DON and NIV were extracted with methanol-water (3:1) and purified by Florisol column. The mycotoxins in the column eluates were derived by TMS reagent and then analysed by gas chromatography with electron capture detector. The average recoveries of DON and NIV, as counted into wheat, at 100, 500, 1,000 and 2000 ppb were 81.2% and 74.5% respectively. The limits of detection of toxins of wheat were 10 ppb for both DON and NIV.