The flavor characteristics and antioxidant capability of aged Jinhua white tea and the mechanisms of its dynamic evolution during long-term aging

This study explored the sensory characteristics, metabolites and antioxidant capability of aged Jinhua white tea (AJWT) over different years of aging and revealed the transformation mechanism of these characteristics during the long-term aging process. The flavor wheel of AJWT was constructed, and its unique flavor was dominated by mellowness, smoothness, a fungus fragrance, and a stale flavor. The high content of theabrownine, soluble sugar, flavonoids and 25 aroma components made important contributions to the formation of the unique flavor of the AJWT, and their content significantly increased during the long-term aging process of 5-10 years. This was related to the microbial bioconversion, the oxidative degradation of catechins, the hydrolysis of flavonosides and the decomposition of polysaccharides. Contrary to folk experience, AJWT had weak comprehensive antioxidant capacity, mainly due to its low content of tea polyphenols, catechin components and caffeine, which decreased significantly during the long-term aging of 5-10 years.

Genome-wide identification, expression profiling, and protein interaction analysis of the CCoAOMT gene family in the tea plant (Camellia sinensis)

BACKGROUND

The caffeoyl-CoA-O methyltransferase (CCoAOMT) family plays a crucial role in the oxidative methylation of phenolic substances and is involved in various plant processes, including growth, development, and stress response. However, there is a limited understanding of the interactions among CCoAOMT protein members in tea plants.

RESULTS

In this study, we identified 10 members of the CsCCoAOMT family in the genome of Camellia sinensis (cultivar 'HuangDan'), characterized by conserved gene structures and motifs. These CsCCoAOMT members were located on six different chromosomes (1, 2, 3, 4, 6, and 14). Based on phylogenetic analysis, CsCCoAOMT can be divided into two groups: I and II. Notably, the CsCCoAOMT members of group Ia are likely to be candidate genes involved in lignin biosynthesis. Moreover, through the yeast two-hybrid (Y2H) assay, we established protein interaction networks for the CsCCoAOMT family, revealing 9 pairs of members with interaction relationships.

CONCLUSIONS

We identified the CCoAOMT gene family in Camellia sinensis and conducted a comprehensive analysis of their classifications, phylogenetic and synteny relationships, gene structures, protein interactions, tissue-specific expression patterns, and responses to various stresses. Our findings shed light on the evolution and composition of CsCCoAOMT. Notably, the observed interaction among CCoAOMT proteins suggests the potential formation of the O-methyltransferase (OMT) complex during the methylation modification process, expanding our understanding of the functional roles of this gene family in diverse biological processes.

[The effect of glucose-6-phosphate dehydrogenase deficiency on allogeneic hematopoietic stem cell transplantation in patients with hematological disorders]

Objectives: To determine the effect of glucose-6-phosphate-dehydrogenase (G6PD) deficiency on patients' complications and prognosis following allogeneic stem cell hematopoietic transplantation (allo-HSCT) . Methods: 7 patients with G6PD deficiency (study group) who underwent allo-HSCT at Peking University People's Hospital from March 2015 to January 2021 were selected as the study group, and thirty-five patients who underwent allo-HSCT during the same period but did not have G6PD deficiency were randomly selected as the control group in a 1∶5 ratio. Gender, age, underlying diseases, and donors were balanced between the two groups. Collect clinical data from two patient groups and perform a retrospective nested case-control study. Results: The study group consisted of six male patients and one female patient, with a median age of 37 (range, 2-45) years old. The underlying hematologic diseases included acute myeloid leukemia (n=3), acute lymphocytic leukemia (n=2), and severe aplastic anemia (n=2). All 7 G6PD deficiency patients achieved engraftment of neutrophils within 28 days of allo-HSCT, while the engraftment rate of neutrophils was 94.5% in the control group. The median days of platelet engraftment were 21 (6-64) d and 14 (7-70) d (P=0.113). The incidence rates of secondary poor graft function in the study group and control group were 42.9% (3/7) and 8.6% (3/35), respectively (P=0.036). The CMV infection rates were 71.4% (5/7) and 31.4% (11/35), respectively (P=0.049). The incidence rates of hemorrhagic cystitis were 57.1% (4/7) and 8.6% (3/35), respectively (P=0.005), while the bacterial infection rates were 100% (7/7) and 77.1% (27/35), respectively (P=0.070). The infection rates of EBV were 14.3% (1/7) and 14.3% (5/35), respectively (P=1.000), while the incidence of fungal infection was 14.3% (1/7) and 25.7% (9/35), respectively (P=0.497). The rates of post-transplant lymphoproliferative disease (PTLD) were 0% and 5.7%, respectively (P=0.387) . Conclusions: The findings of this study indicate that blood disease patients with G6PD deficiency can tolerate conventional allo-HSCT pretreatment regimens, and granulocytes and platelets can be implanted successfully. However, after transplantation, patients should exercise caution to avoid viral infection, complications of hemorrhagic cystitis, and secondary poor graft function.

[Clinical features and risk factors for invasive fungal sinusitis after allogeneic hematopoietic stem cell transplantation]

Objective: To analyze the clinical characteristics and outcomes of patients with invasive fungal sinusitis (invasive fungal rhinosinusitis, IFR) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and explored the risk factors for IFR after allo-HSCT. Methods: Nineteen patients with IFR after allo-HSCT at Peking University People's Hospital from January 2012 to December 2021 were selected as the study group, and 95 patients without IFR after allo-HSCT during this period were randomly selected as the control group (1:5 ratio) . Results: Nineteen patients, including 10 males and 9 females, had IFR after allo-HSCT. The median age was 36 (10-59) years. The median IFR onset time was 68 (9-880) days after allo-HSCT. There were seven patients with acute myeloid leukemia, five with acute lymphoblastic leukemia, two with myelodysplastic syndrome, two with chronic myeloid leukemia, one with acute mixed-cell leukemia, one with multiple myeloma, and one with T-lymphoblastic lymph node tumor. There were 13 confirmed cases and 6 clinically diagnosed cases. The responsible fungus was Mucor in two cases, Rhizopus in four, Aspergillus in four, and Candida in three. Five patients received combined treatment comprising amphotericin B and posaconazole, one patient received combined treatment comprising voriconazole and posaconazole, nine patients received voriconazole, and four patients received amphotericin B. In addition to antifungal treatment, 10 patients underwent surgery. After antifungal treatment and surgery, 15 patients achieved a response, including 13 patients with a complete response and 2 patients with a partial response. Multivariate analysis revealed that neutropenia before transplantation (P=0.021) , hemorrhagic cystitis after transplantation (P=0.012) , delayed platelet engraftment (P=0.008) , and lower transplant mononuclear cell count (P=0.012) were independent risk factors for IFR after allo-HSCT. The 5-year overall survival rates in the IFR and control groups after transplantation were 29.00%±0.12% and 91.00%±0.03%, respectively (P<0.01) . Conclusion: Although IFR is rare, it is associated with poor outcomes in patients undergoing allo-HSCT. The combination of antifungal treatment and surgery might be effective.

[Impact of SARS-CoV-2 infection on graft composition and early transplant outcomes following allogeneic hematopoietic stem cell transplantation]

Objective: To assess the feasibility of using donors with novel coronavirus disease 2019 (COVID-19) for allogeneic hematopoietic stem cell transplantation (allo-HSCT) when there are no other available donors and allo-HSCT cannot be delayed or discontinued. Methods: Seventy-one patients with malignant hematological diseases undergoing allo-HSCT between December 8, 2022, and January 10, 2023, were included. Of these, 16 received grafts from donors with mild COVID-19 (D-COVID(+) group) and 55 received grafts from donors without COVID-19 (D-COVID(-) group). The graft compositions were compared between the two groups. Engraftment, acute graft-versus-host disease (aGVHD), overall survival (OS), and relapse were also evaluated. Results: There were no serious side effects or adverse events in the D-COVID(+) group. The mononuclear cell dose and CD34(+) cell dose were comparable between the two groups, and no additional apheresis was required. There were no significant differences in the lymphocyte, monocyte, and T-cell subset doses between the two groups. The median natural killer cell dose in the D-COVID(+) group was significantly higher than that in the D-COVID(-) group (0.69×10(8)/kg vs. 0.53×10(8)/kg, P=0.031). The median follow-up time was 72 (33-104) days. All patients achieved primary engraftment. The 60-day platelet engraftment rates in the D-COVID(+) and D-COVID(-) groups were 100% and (96.4±0.2) %, respectively (P=0.568). There were no significant differences in neutrophil (P=0.309) and platelet (P=0.544) engraftment times. The cumulative incidence of grade 2-4 aGVHD was (37.5±1.6) % vs. (16.4±0.3) % (P=0.062), and of grade 3-4 aGVHD was 25.0% ±1.3% vs. 9.1% ±0.2% (P=0.095) in the D-COVID(+) and D-COVID(-) groups, respectively. The probabilities of 60-day OS were 100% and 98.1% ±1.8% (P=0.522) in the D-COVID(+) and D-COVID(-) groups, respectively. There was no relapse of primary disease during the study period. Conclusion: When allo-HSCT cannot be delayed or discontinued and no other donor is available, a donor with mild COVID-19 should be considered if tolerable. Larger sample sizes and longer follow-up periods are required to validate these results.

Comparison of Supraclavicular Surgery plus Radiotherapy vs. Radiotherapy Alone in Breast Cancer Patients with Synchronous Ipsilateral Supraclavicular Lymph Node Metastasis: A Multicenter Retrospective Study

PURPOSE/OBJECTIVE(S)

To evaluate and compare the outcomes of supraclavicular lymph node dissection (SLND) plus radiotherapy (RT) and RT alone for patients with synchronous ipsilateral supraclavicular lymph node metastasis (sISLM).

MATERIALS/METHODS

In all, 293 patients with sISLM across three centers were included. Of these, 85 (29.0%) received SLND plus RT and 208 (71.0%) received RT alone. All patients received preoperative systemic therapy followed by mastectomy or lumpectomy and axillary dissection. Supraclavicular recurrence-free survival (SCRFS), locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS) were evaluated by using the Kaplan-Meier method and multivariate Cox models. Multiple imputation was used for missing data.

RESULTS

The median follow-up duration of the RT and SLND+RT groups were 53.7 and 63.5 months, respectively. For the RT and SLND+RT groups, the 5-year SCRFS rates were 91.7% vs. 85.5% (P = 0.522), LRRFS rates were 79.1% vs. 73.1% (P = 0.412), DMFS rates were 60.4 vs. 58.8% (P = 0.708), DFS rates were 57.6% vs. 49.7% (P = 0.291), and OS rates were 71.9% vs. 62.2% (P = 0.272), respectively. There was no significant effect on any outcome when comparing SLND+RT versus RT alone in the multivariate analysis. Based on four risk factors of DFS, patients were classified into three risk groups: the intermediate- and high-risk groups had significantly lower survival outcomes than the low-risk group. SLND+RT did not improve outcomes of any risk group compared with RT alone.

CONCLUSION

Patients with sISLM may not benefit from SLND. Distant metastasis remained the major failure pattern, especially for intermediate- and high-risk groups with sISLM may not benefit from SLND. Distant metastasis remained the major failure pattern, especially for intermediate- and high-risk groups.

[Developmental effects of TCIPP and TnBP on zebrafish (Danio rerio) embryos]

Objective: To investigate the toxicity of tris (2-chloropropyl) phosphate (TCIPP) and tributyl phosphate (TnBP) on the growth and development of zebrafish embryos, as well as to explore the underlying mechanisms at the transcriptional level. Methods: With zebrafish as a model, two hpf zebrafish embryos were exposed to TCIPP and TnBP (0.1, 1, 10, 100, 500, and 1 000 μmol/L) using the semi-static method, and their rates of lethality and hatchability were determined. The transcriptome changes of 120 hpf juvenile zebrafish exposed to environmentally relevant concentrations of 0.1 and 1 μmol/L were measured. Results: The 50% lethal concentrations (LC₅₀) of TCIPP and TnBP for zebrafish embryos were 155.30 and 27.62 μmol/L (96 hpf), 156.5 and 26.05 μmol/L (120 hpf), respectively. The 72 hpf hatching rates of TCIPP (100 μmol/L) and TnBP (10 μmol/L) were (23.33±7.72)% and (91.67±2.97)%, which were significantly decreased compared with the control group (P<0.05). Transcriptome analysis showed that TnBP had more differential genes (DEGs) than TCIPP, with a dose-response relationship. These DEGs were enriched in 32 pathways in total, including those involved in oxidative stress, energy metabolism, lipid metabolism, and nuclear receptor-related pathways, using the IPA pathway analysis. Among them, three enriched pathways overlapped between TCIPP and TnBP, including TR/RXR activation and CAR/RXR activation. Additionally, DEGs were also mapped onto pathways of LXR/RXR activation and oxidative stress for TnBP exposure only. Conclusion: Both TCIPP and TnBP have growth and developmental toxicities in zebrafish embryos, with distinct biomolecular mechanisms, and TnBP has a stronger effect than TCIPP.

Identification, Characterization and Expression Profiling of the RS Gene Family during the Withering Process of White Tea in the Tea Plant (Camellia sinensis) Reveal the Transcriptional Regulation of CsRS8

Raffinose synthetase (RS) is a key enzyme in the process of raffinose (Raf) synthesis and is involved in plant development and stress responses through regulating Raf content. As a sweetener, Raf makes an important contribution to the sweet taste of white tea. However, studies on the identification, analysis and transcriptional regulation of CsRSs (Camellia sinensis RS genes) are still lacking. In this study, nine CsRSs were identified from the tea plant (Camellia sinensis) genome database. The CsRSs were classified into five groups in the phylogenetic tree. Expression level analysis showed that the CsRSs varied in different parts of the tea plant. Transcriptome data showed that CsRSs could respond to persistent drought and cold acclimation. Except for CsRS5 and CsRS9, the expression pattern of all CsRSs increased at 12 h and decreased at 30 h during the withering process of white tea, consistent with the change trend of the Raf content. Furthermore, combining yeast one-hybrid assays with expression analysis, we found that CsDBB could potentially regulate the expression of CsRS8. Our results provide a new perspective for further research into the characterization of CsRS genes and the formation of the white tea flavour.

A food-grade vector for Streptococcus thermophilus based on the α-complementation of β-galactosidase

Streptococcus thermophilus is a common yogurt starter that consumes lactose as its primary carbon source. The enzyme β-galactosidase is essential for the lactose metabolism and the growth of this species. Streptococcus thermophilus appears to be a promising cell factory. Food-grade vectors have advantages in heterologous protein expression. This study aimed to determine whether the β-galactosidase of S. thermophilus has the α-complementary characteristic and to develop a novel food-grade vector based on this phenomenon. The N-terminal 7 to 36 AA residues of the β-galactosidase in S. thermophilus were deleted. The obtained mutant S. thermophilus Δα lost β-galactosidase activity and growth ability in the lactose medium. Subsequently, plasmids expressing α-fragments with different lengths of 1 to 36 (Sα1), 1 to 53 (Sα2), and 1 to 88 (Sα3) AA were constructed and transformed into S. thermophilus Δα. Recombinant S. thermophilus Δα expressing Sα2 or Sα3 recovered the ability to grow in the lactose medium, and their β-galactosidase activity accounted for 24.5% or 11.5% of the wild strain, respectively. These results indicated that the α-complementation system of β-galactosidase existed in S. thermophilus. Based on the characteristic, a food-grade vector pSEα was constructed. Except for Sα2, vector pSEα expressed the α-donor derived from E. coli β-galactosidase. This facilitated the construction of recombinant plasmids in E. coli DH5α and thus improved the transformation efficiency of S. thermophilus. Green fluorescent protein as a reporter protein could be highly expressed in S. thermophilus using this vector. As a result, pSEα is an efficient and safe vector for S. thermophilus with potential food applications.

Longitudinal Cognitive Decline in Patients With Mild Cognitive Impairment or Dementia Due to Alzheimer's Disease

Sensitive cognitive assessments accurately detect and track cognitive decline in Alzheimer's disease. The Cogstate battery was used to measure cognitive change in cognitively normal participants and in individuals with mild cognitive impairment and mild Alzheimer's disease enrolled in the Australian Imaging, Biomarker and Lifestyle Rate of Change Substudy. Over 18 months, verbal episodic memory performance declined for mild cognitive impairment and mild Alzeheimer's disease groups when compared to cognitively normal participants. Frequent assessments of episodic memory may facilitate early detection of cognitive decline due to Alzheimer's disease.

Site-directed mutation of β-galactosidase from Streptococcus thermophilus for galactooligosaccharide-enriched yogurt making

β-Galactosidase is one of the most important enzymes used in dairy processing. It converts lactose into glucose and galactose, and also catalyzes galactose to form galactooligosaccharides (GOS), so-called prebiotics. However, most of the β-galactosidases from the starter cultures have low transgalactosylation activities, the process that results in galactose accumulation in yogurt. Here, a site-directed mutation strategy was attempted, to genetically modify β-galactosidase from Streptococcus thermophilus. Out of 28 Strep. thermophilus strains, a β-galactosidase gene named bgaQ, encoded for high β-galactosidase hydrolysis activity (BgaQ), was cloned from the strain Strep. thermophilus SDMCC050237. It was 3,081 bp in size, with 1,027 deduced amino acid residuals, which belonged to the GH2 family. After replacing the Tyr⁸⁰¹ and Pro⁸⁰² around the active sites of BgaQ with His⁸⁰¹ and Gly⁸⁰², the GOS synthesis of the generated mutant protein BgaQ-8012 increased from 20.5% to 26.7% at 5% lactose, and no hydrolysis activity altered obviously. Subsequently, the purified BgaQ or BgaQ-8012 was added to sterilized milk inoculated with 2 starters from Strep. thermophilus SDMCC050237 and Lactobacillus delbrueckii ssp. bulgaricus ATCC11842. The GOS yields with added BgaQ or BgaQ-8012 rose to 5.8 and 8.3 g/L, respectively, compared with a yield of 3.7 g/L without enzymes added. Meanwhile, the addition of the BgaQ or BgaQ-8012 reduced the lactose content by 49.3% and 54.4% in the fermented yogurt and shortened the curd time. Therefore, this study provided a site-directed mutation strategy for improvement of the transgalactosylation activity of β-galactosidase from Strep. thermophilus for GOS-enriched yogurt making.

Squeezed-Light Enhancement and Backaction Evasion in a High Sensitivity Optically Pumped Magnetometer

We study the effect of optical polarization squeezing on the performance of a sensitive, quantum-noise-limited optically pumped magnetometer. We use Bell-Bloom (BB) optical pumping to excite a ^{87}Rb vapor containing 8.2×10^{12}  atoms/cm^{3} and Faraday rotation to detect spin precession. The sub-pT/sqrt[Hz] sensitivity is limited by spin projection noise (photon shot noise) at low (high) frequencies. Probe polarization squeezing both improves high-frequency sensitivity and increases measurement bandwidth, with no loss of sensitivity at any frequency, a direct demonstration of the evasion of measurement backaction noise. We provide a model for the quantum noise dynamics of the BB magnetometer, including spin projection noise, probe polarization noise, and measurement backaction effects. The theory shows how polarization squeezing reduces optical noise, while measurement backaction due to the accompanying ellipticity antisqueezing is shunted into the unmeasured spin component. The method is compatible with high-density and multipass techniques that reach extreme sensitivity.

[BK virus encephalitis in children with hematopoietic stem cell transplantation]

目的

探讨异基因造血干细胞移植患儿中BK病毒（BKV）脑炎的发病率、病死率、中位发病时间、临床表现、诊治及转归等，以提高临床医师对本病的认识。

方法

回顾性分析2015年1月1日至2020年12月31日在北京大学人民医院接受单倍型造血干细胞移植治疗的709例儿童患者，其中14例诊断为BKV脑炎，分析其临床特征、治疗过程及转归。

结果

BKV脑炎发生率为1.97％（14例）。患儿多为男性（12例），中位年龄为11岁，中位发病时间为移植后第55天。最常见的临床表现为意识障碍、抽搐发作（7例）。14例患儿予阿昔洛韦、更昔洛韦单用，或联合丙种球蛋白治疗，9例患儿痊愈，1例患儿死于病毒性脑炎，4例患儿死于其他疾病，病死率为35.7％。

结论

BKV脑炎主要表现为脑炎或脑膜炎。虽然确诊BKV脑炎后积极予药物治疗，但许多患者仍死于多器官衰竭或其他并发症。当异基因造血干细胞移植患者出现神经系统症状、出血性膀胱炎时，必须高度警惕BKV脑炎，尽早施救，从而改善患者的生存率及生活质量。

Measurement of the Cosmic Ray Helium Energy Spectrum from 70 GeV to 80 TeV with the DAMPE Space Mission

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

Transanal mesorectal excision: early outcomes in Australia and New Zealand

BACKGROUND

Transanal total mesorectal excision (taTME) aims to overcome some of the technical challenges faced when operating on mid and low rectal cancers. Specimen quality has been confirmed previously, but recent concerns have been raised about oncological safety. This multicentre prospective study aimed to evaluate the safety of taTME among early adopters in Australia and New Zealand.

METHODS

Data from all consecutive patients who had taTME for rectal cancer from July 2014 to February 2020 at six tertiary referral centres in Australasia were recorded and analysed.

RESULTS

A total of 308 patients of median age of 64 years underwent taTME. Some 75.6 per cent of patients were men, and the median BMI was 26.8 kg/m2. The median distance of tumour from anal verge was 7 cm. Neoadjuvant chemoradiotherapy was administered to 57.8 per cent of patients. The anastomotic leak rate was 8.1 per cent and there was no mortality within 30 days of surgery. Pathological examination found a complete mesorectum in 295 patients (95.8 per cent), a near-complete mesorectum in seven patients (2.3 per cent), and an incomplete mesorectum in six patients (1.9 per cent). The circumferential resection margin and distal resection margin was involved in nine patients (2.9 per cent), and two patients (0.6 per cent) respectively. Over a median follow-up of 22 months, the local recurrence rate was 1.9 per cent and median time to local recurrence was 30.5 months.

CONCLUSION

This study showed that, with appropriate training and supervision, skilled minimally invasive rectal cancer surgeons can perform taTME with similar pathological and oncological results to open and laparoscopic surgery.

MiR-1301 promotes adipogenic and osteogenic differentiation of BMSCs by targeting Satb2

OBJECTIVE

Bone marrow mesenchymal stem cells (BMSCs) have the ability to differentiate into several cell lines and are critical for skeletal microenvironment and bone development. MiR-1301 is involved in multiple pathological and physiological processes. However, miR-1301's role in BMSCs adipogenic and osteogenic differentiation remains unclear.

MATERIALS AND METHODS

Rat BMSCs were isolated and randomly divided into control group, miR-1301 group, and miR-1301 siRNA group followed by analysis of the expression of miR-1301, Bax, Bcl-2, UNX2, and OPN, as well as FABP4 and PPARγ2 by Real Time-PCR. Cell proliferation was assessed by MTT assay and the relationship between miR-1301 and Satb2 was evaluated by the Dual-Luciferase reporter assay. Satb2 expression was detected by Western blot.

RESULTS

The pcDNA-miR-1301 plasmid was transfected into BMSCs to upregulate the expression of miR-1301, which promoted cell proliferation, decreased Bax expression, and increased Bcl-2 expression and ALP activity. In addition, it also elevated the expression of RUNX2 and OPN and decreased the expression of FABP4, PPARγ2, and Satb2. Compared with the control group, the difference was statistically significant (p<0.05); Satb2 was the target gene of miR-1301. MiR-1301 siRNA transfected into BMSCs down-regulated miR-1301 expression, inhibited cell proliferation, increased Bax expression and decreased Bcl-2 expression and ALP activity. Meanwhile, miR-1301 siRNA also reduced RUNX2 and OPN expression and increased expression of FABP4, PPARγ2 and Satb2. The difference was statistically significant compared with control group (p<0.05).

CONCLUSIONS

Regulation of miR-1301 expression in BMSCs can improve BMSCs proliferation and regulate their adipogenic and osteogenic differentiation by regulating Satb2.

Peptide transporter-related protein 2 plays an important role in glutathione transport of Streptococcus thermophilus

Streptococcus thermophilus is widely used as a starter culture in the fermentation of yogurt. Glutathione (GSH; γ-glutamyl-cysteinyl-glycine), as a tripeptide, has an important physiological role for Strep. thermophilus. However, the scope of the GSH transport proteins is still unexplored in this species. In the present study, 5 peptide transporter-related proteins (Ptrp) of Strep. thermophilus strain ST-1 were selected and then inactivated by gene insertion, respectively. Through detection and comparison of intracellular GSH content of mutant strain and wild strain, we identified 2 proteins, named Ptrp-2 and Ptrp-4, that might be related to GSH transport. Reverse-transcriptase quantitative PCR was performed to verify the gene expressions of these 2 possible GSH transport-related proteins, and it was finally determined that Ptrp-2 plays an important role in GSH transport of Strep. thermophilus. Milk fermentation experiments were further conducted to test the effect of Ptrp-2 on the characteristics of yogurt. The results showed that the fermented milk hardly curds using the mutant strain, indicating that Ptrp-2 is important for Strep. thermophilus as a yogurt starter.

Prognostic factors influencing survival in patients undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for isolated colorectal peritoneal metastases: a systematic review and meta-analysis

AIM

Peritoneal metastases from colorectal cancer confer the worst survival among all metastatic sites. The adoption of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) can offer selected patients with isolated colorectal peritoneal metastases (CRPM) a favourable long-term survival. There are numerous factors postulated to influence survival in patients undergoing CRS and HIPEC. The aim of this study was to identify the key perioperative prognostic factors that influence survival in patients undergoing CRS and HIPEC for isolated CRPM.

METHOD

A systematic review and meta-analysis were conducted to evaluate prognostic factors influencing survival in patients undergoing CRS and HIPEC for isolated CRPM.

RESULTS

Thirty-three studies fitted the inclusion criteria for the systematic review, with 25 studies included in the meta-analysis. On pooled analysis, incomplete cytoreduction, increasing peritoneal carcinoma index (PCI) and lymph node involvement were significantly associated with a worse survival. Additionally, a rectal primary [hazard ratio (HR) 1.93, 95% CI 1.10-3.37], adjuvant chemotherapy (HR 0.71, 95% CI 0.54-0.93) and perioperative grade III/IV morbidity (HR 1.59, 95% CI 1.17-2.16) were also found to significantly influence survival. Notably, tumour differentiation and signet ring cell histology did not influence survival on pooled analysis.

CONCLUSION

This meta-analysis confirms that in patients undergoing CRS and HIPEC for isolated CRPM, incomplete cytoreduction, high PCI and lymph node involvement have a negative influence on survival. In addition, a rectal primary, adjuvant chemotherapy use and grade III/IV morbidity are important factors that also significantly influence survival.

Measurement of the cosmic ray proton spectrum from 40 GeV to 100 TeV with the DAMPE satellite

The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 ¹/₂ years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

[Clinical analysis of hemorrhagic cystitis in children and adolescents with hematological diseases post haplo-hematopoietic stem cell transplantation]

目的

观察儿童及青少年血液病患者单倍型造血干细胞移植（haplo-HSCT）后出血性膀胱炎（HC）的临床特征并探讨其影响因素。

方法

回顾性分析2015至2016年接受haplo-HSCT的89例儿童及青少年血液病患者的临床资料。

结果

全部89例患者中，≤14岁62例（儿童组）、>14~<18岁27例（青少年组）；男56例，女33例；中位移植年龄10（1~17）岁；急性淋巴细胞白血病（ALL）44例，急性髓系白血病（AML）33例，急性混合细胞白血病（AHL）3例，骨髓增生异常综合征（MDS）9例。移植物来源均为骨髓+外周血干细胞。全部89例患者中32例（36%）发生HC，其中迟发型31例，早发型1例；Ⅰ度6例、Ⅱ度16例、Ⅲ度8例、Ⅳ度2例；HC发病中位时间为移植后25（2~55）d，中位持续时间为19（3~95）d；所有患儿均获得治愈。儿童组HC发病率低于青少年组[27.4%（17/62）对55.6%（15/27），χ²=6.466，P<0.05]。儿童组中<5岁组HC发生率低于5~14岁组[0（0/12）对34%（17/50），χ²=4.043，P<0.05]。

结论

HC是儿童及青少年血液病患者haplo-HSCT的常见并发症，总体预后良好，年龄是其发生的影响因素。

IgG1+ B-cell immunity predates IgE responses in epicutaneous sensitization to foods

BACKGROUND

The generation of IgE-mediated food allergy in humans is silent and only diagnosed upon manifestation of clinical symptoms. While experimental models have been used to investigate some mechanisms of allergic sensitization, the generation of humoral immunity and memory remains to be elucidated. Here, we defined the evolution of allergen-specific B-cell responses during epicutaneous sensitization to foods.

METHODS

Wild-type and genetic knockout animals, and drug or antibody strategies for cell depletion and immunoglobulin signaling blockade were used to investigate epicutaneous sensitization and disease progression; we analyzed allergen-specific germinal centers and IgG1⁺ memory B cells by flow cytometry, evaluated humoral responses, and determined clinical reactivity (anaphylaxis).

RESULTS

Epicutaneous sensitization caused microscopic skin damage, inflammation, and recruitment of activated dendritic cells to the draining lymph nodes. This process generated allergen-specific IgG1⁺ germinal center B cells, serum IgG1, and anaphylaxis that was mediated by the alternative pathway. Whether we used peanut and/or ovalbumin from the egg white for sensitization, the allergen-specific IgG1⁺ memory compartment predominantly exhibited an immature, pro-germinal center phenotype (PDL-2^- CD80^- CD35⁺ CD73⁺ ). Subsequent subclinical exposures to the allergen induced IgE⁺ germinal center B cells, serum IgE, and likely activated the classical pathway of anaphylaxis.

CONCLUSIONS

Our data demonstrate that IgG1⁺ B-cell immunity against food allergens in epicutaneous sensitization precedes the generation of IgE responses. Therefore, the assessment of allergen-specific cellular and humoral IgG1⁺ immunity may help to identify individuals at risk of developing IgE-mediated food allergy and hence provide a window for therapeutic interventions.

[Pharmacokinetics of generic dasatinib in the management of chronic myeloid leukemia in the choronie phase]

Objective: To evaluate the pharmacokinetics and bioequivalence of generic dasatinib in patients with chronic myeloid leukemia in the choronie phase (CML-CP). Methods: Using randomized, parallel, overlapping, self-control designed study, a 100 mg dose of the reference or test tablet was given to 12 CML-CP patients who were resistant or intolerant to Imatinib and Nilotinib in a randomized two-way crossover design, and the plasma concentration of the medicine was assayed by HPLC-MS-MS. The main pharmacokinetic parameters and bioequivalence of the two formulations were evaluated. Results: The major pharmacokinetic parameters were as follows: C_max (209.01±58.69) μg/L and (223.07±79.51) μg/L, T_max (1.1±0.8) h and (1.1±0.8) h, T_1/2 (5.10±1.34) h and (4.39±0.74) h, AUC_0-τ (646.65±185.67) h·μg/L and (695.84±273.40) h·μg/L (all P>0.05); AUC_0-∝ (668.11±186.00) h·μg/L and (712.42±278.08) h·μg/L, MRT (5.32 ± 1.70) h and (4.68 ± 1.53) h (all P>0.05). Conclusion: The two formulations were bioequivalent.

GRAPHITE: A Graphical Environment for Scalable in situ Video Tracking of Moving Insects

1. Methods for measuring animal movement are critical for understanding numerous ecological and evolutionary processes. However, few methods are available for small organisms, and even fewer methods offer consistent individual-level resolution while remaining affordable, scalable and operable in the field. 2. We describe a low-cost animal movement tracking method with a user-friendly graphical interface, called GRAPHITE. Our automated software can quantify motions of insects by offline video analysis of inexpensive and lightweight human-readable tags attached to individual insects. The integrated graphical editor provides a full-featured environment for users to review the generated tracking data and make individual- or group-level edits. 3. GRAPHITE is a novel video analysis and graphical editing software (MATLAB v.9.0.0+) that identifies tags in image frames with a minimal false negative rate, links sequences of corresponding tags into "tracks" for each individual insect, infers the tag identifier, and provides a user-friendly graphical environment for editing tracking data. Users can either batch process raw video data using the full analysis pipeline or execute GRAPHITE modules independently for a tailored analysis. 4. We demonstrate the efficacy of the developed software with a specific application to the movement of honey bees at the entrance of hives. However, this system can be easily modified to track individually marked insects of 3 mm and larger. A notable advantage of this method is its ability to provide easy access to individual-level tracking data using human-readable tags.

[A preliminary study on the application of two-point traction with guidewire method in percutaneous transhepatic sinus tract dilation]

Objective: To explore the feasibility and effectiveness of the two-point traction with guidewire method to improve the safety of percutaneous transhepatic sinus tract dilation. Methods: The clinical data of 18 patients underwent the two-point traction guided by percutaneous transhepatic sinus dilation between January 2013 and July 2017 in Shengjing Hospital of China Medical University were analyzed retrospectively. The operation time, volume of intraoperative blood loss and postoperative complications were recorded. Results: All of the 18 patients were treated successfully. The mean size of the percutaneous transhepatic sinus tract was (18.6±2.3) Fr. The operation time was 15-45 min, with an average of 30 minutes, and the average intraoperative blood loss was about 11.7 ml. The incidence of postoperative complications was 22.2% (4/18), including cholangitis in 3 patients, pancreatitis in 1 case. All the complications were relieved after symptomatic treatment, no severe complications (biliary tract perforation or severe haemorrhage) occurred. A total of (3.3 ± 2.6) times cholangioscopic explorations for stone extraction were performed, with a overall clearance rate of 64.7% (11/17). Conclusions: From the results of limited patient data in this group, the two-point traction with guidewire can provide the exact guidance for percutaneous transhepatic sinus tract dilation, which is effective and easily conducted, but still need further clinical study to confirm.

[Metabolic Characteristics of Lethal Bradycardia Induced by Myocardial Ischemia]

OBJECTIVES

To explore the metabolic characteristics of lethal bradycardia induced by myocardial ischemia in rat's serum.

METHODS

A rat myocardial ischemia-bradycardia-sudden cardiac death （MI-B-SCD） model was established, which was compared with the sham-operation group. The metabolic profile of postmortem serum was analyzed by gas chromatography-mass spectrometry （GC-MS）, coupled with the analysis of serum metabolic characteristics using metabolomics strategies.

RESULTS

The serum metabolic profiles were significantly different between the MI-B-SCD rats and the control rats. Compared to the control rats, the MI-B-SCD rats had significantly higher levels of lysine, ornithine, purine, serine, alanine, urea and lactic acid; and significantly lower levels of succinate, hexadecanoic acid, 2-ketoadipic acid, glyceraldehyde, hexendioic acid and octanedioic acid in the serum. There were some correlations among different metabolites.

CONCLUSIONS

There is obvious metabolic alterations in the serum of MI-B-SCD rat. Both lysine and purine have a high value in diagnosing MI-B-SCD. The results are expected to provide references for forensic and clinical applications of prevention and control of sudden cardiac death.

Experimental study of delivery of humidified-warm carbon dioxide during open abdominal surgery

Background

The aim of this study was to monitor the effect of humidified‐warm carbon dioxide (HWCO₂) delivered into the open abdomen of mice, simulating laparotomy.

Methods

Mice were anaesthetized, ventilated and subjected to an abdominal incision followed by wound retraction. In the experimental group, a diffuser device was used to deliver HWCO₂; the control group was exposed to passive air flow. In each group of mice, surgical damage was produced on one side of the peritoneal wall. Vital signs and core temperature were monitored throughout the 1‐h procedure. The peritoneum was closed and mice were allowed to recover for 24 h or 10 days. Tumour cells were delivered into half of the mice in each cohort. Tissue was then examined using scanning electron microscopy and immunohistochemistry.

Results

Passive air flow generated ultrastructural damage including mesothelial cell bulging/retraction and loss of microvilli, as assessed at 24 h. Evidence of surgical damage was still measurable on day 10. HWCO₂ maintained normothermia, whereas open surgery alone led to hypothermia. The degree of tissue damage was significantly reduced by HWCO₂ compared with that in controls. Peritoneal expression of hypoxia inducible factor 1α and vascular endothelial growth factor A was lowered by HWCO₂. These effects were also evident at the surgical damage sites, where protection from tissue trauma extended to 10 days. HWCO₂ did not reduce tumorigenesis in surgically damaged sites compared with passive air flow.

Conclusion

HWCO₂ diffusion into the abdomen in the context of open surgery afforded tissue protection and accelerated tissue repair in mice, while preserving normothermia.

The global regulator CodY responds to oxidative stress by the regulation of glutathione biosynthesis in Streptococcus thermophilus

CodY_st is a global transcriptional regulator that modulates the metabolic network in Streptococcus thermophilus ST2017. In this study, experimental data showed that the cell survival of the codY_st defective mutant obviously declined at the presence of 10 mM H₂O₂, suggesting CodY_st was involved in response to the oxidative stress. To investigate this phenomenon, transcriptome analysis and real time-quantitative PCR were performed and the results indicated that the transcriptional level of a bifunctional glutathione synthetase gene (gshF) was downregulated by about 3-fold in the codY_st defective mutant, along with a decrease by 20% of the glutathione yield compared with the wild-type in minimal chemical defined medium, whereas half of the viable cells remained after H₂O₂ challenge. In vitro gel shift assays showed that the purified CodY_st could bind to the promoter region of gshF, with a conserved CodY_st box, confirming the regulation of CodY_st on the gshF gene. To our knowledge, this is first report of CodY_st in response to oxidative stress mediated by the regulation of gshF in S. thermophilus.

In the face of pain: The choice of visual cues in pain conditioning matters

BACKGROUND

Visual cue conditioning is a valuable experimental paradigm to investigate placebo and nocebo effects in pain. However, little attention has been paid to the cues themselves and potential variability of effects (their quantity and quality) stemming from the choice of stimuli. Yet, this seemingly methodological question has important implications for the interpretation of experimental findings in terms of their significance for clinical practice.

METHODS

We investigated the effect of heat pain conditioning using different types of visual cues (abstract images, faces and pseudo-words) in a group of 22 healthy volunteers. We analysed conditioning effects calculated as the difference in pain ratings to heat stimuli of identical temperature preceded by conditioned high or low pain cues with (1) subliminal and supraliminal presentation; and (2) immediately after conditioning and following extinction. Awareness manipulation and test following indirect, observational extinction allowed us to assess the strength and robustness of the conditioning effects induced with different cue types.

RESULTS

We observed no differences in conditioning effect magnitudes between images, faces and words when all stimuli were presented supraliminally. With subliminal presentation, only face stimuli elicited a significant effect; equally only face cue-induced effect withstood extinction.

CONCLUSIONS

Our findings indicate that face-related associations to pain might be stronger than those elicited with other visual cues, as face cues seem to induce stronger subliminal effects and withstand mild extinction.

SIGNIFICANCE

We compared different types of neutral cues commonly used in conditioning paradigms and found that faces elicited a stronger, more robust nonconscious effect than abstract images or pseudo-words.