[Efficacy and initial clinical evaluation of optical genome mapping in the diagnosis of structural variations].

To investigate the efficacy and value of optical genome mapping (OGM) in detecting chromosomal structural variations. In a clinical study about high-precision analysis of genomic structural variation for complex genetic diseases, a retrospective study was performed on the cases with karyotyping at the department of Obstetrics and Gynecology, and Endocrinology of Peking Union Medical College Hospital from January to December 2021. Ten cases with abnormal karyotype was detected by OGM. Partial cases were verified by fluorescence in situ hybridization (FISH), SNP array or CNV-seq. Results of ten cases, nine were detected with abnormality by OGM, including unbalanced chromosomal rearrangements (n=3), translocation (n=5) and paracentric inversion (n=1), and the results were in concordance with other standard assays. However, one case with breakpoint and reconnected at centromere has not been detected. In conclusion, ten samples were comprehensively analyzed by karyotyping, FISH, SNP array or CNV-seq, and OGM, and results demonstrated that optical genome mapping as a new technology can not only detect unbalanced rearrangements such as copy number variants as well as balanced translocations and inversions, but more importantly, it can refine breakpoints and orientation of duplicated segments or insertions. So it can contribute to the diagnosis of genetic diseases and prevent birth defect. However, the current technology is not yet capable of detecting breakpoints of balanced structural variations lying within unmapped regions.

Electric-field-tunable molecular adsorption on germanane.

Fully-hydrogenated germanene, named germanane, represents a new nanostructured material for a variety of potential applications, such as electronics and optoelectronics. However, a critical requirement for developing practical and reliable electronic devices based on germanane consists of achieving a flexibly controllable charge carrier and doping level. Different to the conventional doping methods such as ion implantation and diffusion, by first-principles calculations we demonstrate that tetracyanobenzene (TCNB) molecular adsorption could introduce effective p-type doping in germanane due to the combination of germanane with electroactive acceptor molecule TCNB. The corresponding energy difference between the empty band minimum of the dopant and the valence band maximum for electron excitation is 0.173 eV. More importantly, this nondestructive p-type doping could be linearly tuned under an external E-field. Analysis of charge transfer by means of the equivalent capacitor model and the shift of energy levels in the superstructure of germanane/TCNB further reveals that the superposition of the external E-field and molecular adsorption-induced internal E-field plays a key role in the charge transfer between TCNB and germanane, especially in achieving a controllable p-type molecular doping level in germanane. Such convenient and flexible E-field-engineering of p-type molecular doping in germanane would be very helpful for potential applications of germanane-based electronic and optoelectronic devices in the future.

[Optimal cessation period of anti-HBV therapy to block mother-to-child transmission].

Hepatitis B virus (HBV) carrier woman of childbearing age with high viral load is an important source of vertical transmission of hepatitis b virus from mother-to-child in China. Routine blockade with immunoglobulin combined with hepatitis B vaccine is used for neonates born to pregnant women with high viral load of hepatitis B virus, but in some cases, immunoprophylaxis fails. The main application of antiviral drugs in pregnancy is to reduce the serum viral load, thereby significantly improve the blocking rate of vertical transmission between mother and infant. Current evidence suggested that if the maternal age is less than 30 years old, with no obvious liver fibrosis or cirrhosis and there is no increase in ALT level >2ULN( upper limit of normal) during the treatment, the treatment with antiviral drugs can be stopped after delivery immediately. Additionally, ALT level should be examined at 4, 12 and 24 weeks after stopping the drug. Antiviral therapy for the occurrence of hepatitis attack should be given if criteria for HBV treatment are met.

Strain-tunable molecular doping in germanane: a first-principles study.

Germanane, fully hydrogenated germanene, has recently attracted great interest, both theoretical and experimental. In this paper we thoroughly study strain-tunable n/p-type doping in germanane by adsorption of tetrathiafulvalene (TTF)/tetracyanoquinodimethane (TCNQ) molecules through first-principles calculations. The results show that both TTF and TCNQ molecules can non-covalently functionalize the electronic properties of germanane. Not surprisingly, TTF molecular adsorption induces n-type doping in germanane because the TTF molecule is a typical electron donor. Moreover, a linearly tunable band gap of germanane and differing n-type doping strengths can be realized by a biaxial strain ranging from -3% to 3%. Analysis indicates that tensile strain would promote the doping effect whereas compressive strain would inhibit it. Comparatively, TCNQ molecular adsorption induces a germanane/TCNQ system which exhibits metallic characteristics. Surprisingly, however, under a tensile strain of 2.5%, a strong p-type doping effect is achieved in germanene/TCNQ. In particular, with increasing tensile strain over the range 2.5%-3%, the strain-tunable p-type doping effect decreases gradually. Such a multiple effect of molecular adsorption and strain on the electronic properties of germanane could be helpful for potential future applications of germanane-based electron devices.

[Diagnosis and treatment of bacterial infection in patients with end-stage liver disease].

Patients with end-stage liver disease have an increased risk of developing bacterial infections, resulting in an increase in the number of hospitalizations and medical expenses, a decline in the quality of life of patients, and an increased fatality rate. Bacterial infections in patients with end-stage liver disease is mainly due to the falling off the body's immune response causing respiratory infections, spontaneous bacterial peritonitis, urinary tract infections and gastrointestinal infections. The diagnosis of bacterial infection is more challenging because the occurrence of infection shows no typical symptoms and signs. The examination of some biological markers has important clinical significance for early diagnosis. The clinical prognosis is entirely marked on the patient conditions, the effective control of infection, appropriate broad-spectrum antibiotics, and empiric therapy. Antibiotics are the choice, but also need to be alert against drug-induced liver damage.

[Investigation and factor analysis of postoperative surgical site infections in emergency abdominal surgery in China from 2018 to 2021 based on Chinese SSI Surveillance].

Objective: We investigated the incidence of surgical site infection (SSI) following emergency abdominal surgery (EAS) in China and further explored its risk factors, providing a reference for preventing and controlling SSI after EAS. Methods: This was an observational study. Data of patients who had undergone EAS and been enrolled in the Chinese SSI Surveillance Program during 2018-2021were retrospectively analyzed. All included patients had been followed up for 30 days after surgery. The analyzed data consisted of relevant patient characteristics and perioperative clinical data, including preoperative hemoglobin, albumin, and blood glucose concentrations, American Society of Anesthesiologists (ASA) score, grade of surgical incision, intestinal preparation, skin preparation, location of surgical site, approach, and duration. The primary outcome was the incidence of SSI occurring within 30 days following EAS. SSI was defined as both superficial and deep incisional infections and organ/space infections, diagnoses being supported by results of microbiological culture of secretions and pus. Secondary outcomes included 30-day postoperative mortality rates, length of stay in the intensive care unit (ICU), duration of postoperative hospitalization, and associated costs. The patients were classified into two groups, SSI and non-SSI, based on whether an infection had been diagnosed. Univariate and multivariate logistic regression analyses were performed to identify risk factors associated with SSI following EAS. Results: The study cohort comprised 5491 patients who had undergone EAS, comprising 3169 male and 2322 female patients. SSIs were diagnosed in 168 (3.1%) patients after EAS (SSI group); thus, the non-SSI group consisted of 5323 patients. The SSIs comprised superficial incision infections in 69 (41.1%), deep incision infections in 51 (30.4%), and organ or space infections in 48 (28.6%). Cultures of secretions and pus were positive in 115 (68.5%) cases. The most frequently detected organism was Escherichia coli (47/115; 40.9%). There were no significant differences in sex or body mass index between the SSI and non-SSI groups (both P>0.05). However, the proportion of individuals aged 60 years or older was significantly greater in the SSI than in the non-SSI group (49.4% [83/168] vs. 27.5% [1464/5323), χ2=38.604, P<0.001). Compared with the non-SSI group, the SSI group had greater proportions of patients with diabetes (11.9% [20/168] vs. 4.8% [258/5323], χ2=16.878, P<0.001), hypertension (25.6% [43/168] vs. 12.2% [649/5323], χ2=26.562, P<0.001); hemoglobin <110 g/L (27.4% [46/168] vs. 13.1% [697/5323], χ2=28.411, P<0.001), and albuminemia <30 g/L (24.4% [41/168] vs. 5.9% [316/5323], χ2=91.352, P<0.001), and a reduced rate of preoperative skin preparation (66.7% [112/168] vs. 75.9% [4039/5323], χ2=7.491, P=0.006). Furthermore, fewer patients in the SSI group had preoperative ASA scores of between one and two (56.0% [94/168] vs. 88.7% [4724/5323], χ2=162.869, P<0.001) in the non-SSI group. The incidences of contaminated and infected incisions were greater in the SSI group (63.1% [106/168] vs. 38.6% [2056/5323], χ2=40.854, P<0.001). There was a significant difference in surgical site distribution between the SSI and non-SSI groups (small intestine 29.8% [50/168] vs. 10.6% [565/5323], colorectal 26.2% [44/168] vs. 5.6% [298/5 323], and appendix 24.4% [41/168] vs. 65.1% [3465/5323]) χ2=167.897, P<0.001), respectively. There was a significantly lower proportion of laparoscope or robotic surgery in the non-SSI group (24.4 % [41/168] vs. 74.2% [3949/5323], χ2=203.199, P<0.001); the percentage of operations of duration less than 2 hours was significantly lower in the SSI than non-SSI group (35.7% [60/168] vs. 77.4% [4119/5323], χ2=155.487, P<0.001). As to clinical outcomes, there was a higher 30-day postoperative mortality rate (3.0%[5/168] vs. 0.2%[10/5323], χ2=36.807, P<0.001) and higher postoperative ICU occupancy rate (41.7% [70/168] vs. 19.7% [1046/5323], χ2=48.748, P<0.001) in the SSI group. The median length of stay in the ICU (0[2] vs. 0[0] days, U=328597.000, P<0.001), median total length of stay after surgery (16[13] vs. 6[5] days, U=128146.000, P<0.001), and median hospitalization cost (ten thousand yuan, 4.7[4.4] vs. 1.7[1.8], U=175965.000, P<0.001) were all significantly greater in the SSI group. Multivariate logistic regression analysis revealed that the absence of skin preparation before surgery (OR=2.435,95%CI: 1.690-3.508, P<0.001), preoperative albuminemia <30 g/L (OR=1.680, 95%CI: 1.081-2.610, P=0.021), contaminated or infected incisions (OR=3.031, 95%CI: 2.151-4.271, P<0.001), and laparotomy (OR=3.436, 95% CI: 2.123-5.564, P<0.001) were independent risk factors of SSI. Operative duration less than 2 hours (OR=0.465, 95%CI: 0.312-0.695, P<0.001) and ASA score of 1-2 (OR=0.416, 95% CI: 0.289-0.601, P<0.001) were identified as independent protective factors for SSI. Conclusions: It is important to consider the nutritional status in the perioperative period of patients undergoing EAS. Preoperative skin preparation should be conducted and, whenever possible, laparoscope or robot-assisted surgery. Duration of surgery should be as short as possible while maintaining surgery quality and improving patient care.

[Randomized clinical trial of cis-platinum diamminedichloride (PDD) in the treatment of hepatocellular carcinoma (HCC)].

From Oct. 1982 to Apr. 1985, 82 patients with HCC proven by pathology were treated in our hospital. 43 treated by hepatic arterial perfusion, were randomized into PDD group: PDD 10 mg per day X 10, every 3 weeks; control group: fluorouracil (5-Fu) 250 mg per day X 4, every week and thio-tepa (TSPA) 10 mg, twice a week. The other 39 treated by intravenous chemotherapy, were also randomized into PDD group: PDD 20 mg per day X 5, every 3 weeks; control group: 5-Fu 500 mg and TSPA 10 mg, twice a week. The objective response rates were 31.8% (7/22) in PDD group and 23.8% (5/21) in control group by hepatic arterial perfusion, and 20.0% (4/20) in the former and 0% (0/19) in the latter who were treated intravenously. The median survivals were 8 months for all the patients receiving hepatic arterial perfusion, and 6 and 5 months for the intravenous PDD and its control group, respectively. The side effects and kidney toxicity of PDD were tolerable to the patients. It is observed that PDD is better than 5-Fu and TSPA in the treatment of HCC.