Exploratory social network analysis and gene sequencing in people who inject drugs infected with hepatitis C virus.

Social networks facilitate the transmission of hepatitis C virus (HCV) in people who inject drugs (PWID). The aim of this study was to assess how certain network structural characteristics are related to HCV infections in PWID and to determine the most susceptible individuals for HCV transmission in a network of PWID. PWID (N = 80) from central China were recruited from a previous follow-up case-control study. Demographic and behavioural information was obtained from a computerized database for each group. HCV RNA was extracted from blood specimens. Sequences were used to construct a phylogenetic tree and to determine genetic distances. Socio-metric social links were established between participants. Network measures were calculated using UCINET. Three HCV genotypes were identified, covering five subtypes. The density of the social networks for the whole sample (N = 80), case group (n = 31) and control group (n = 49) was 0.038, 0.054 and 0.008, respectively. PWID infected with HCV were in frequent contact with others within their group. There were four pairs of nodes with genotypic distances of 0.000 that were identified and clustered in subtypes 6a and 1b; each subject pair was linked and found in one clique. Three of the five most active nodes were infected with HCV. These three nodes served as a bridge, contributing to the connection of other nodes. These findings identify susceptible individuals for HCV transmission in PWID based on their frequent contact with others in the network. These results provide data that could be used for modelling HCV transmission patterns and in public health policies.

A novel HLA-A allele, HLA-A*02:488, identified by sequence-based typing.

HLA-A*02:488 differs from HLA-A*02:01:01:01 by one nucleotide exchange at position 425(A > G) with an amino exchange.

Botulinum toxin injection versus lateral internal sphincterotomy for chronic anal fissure: a meta-analysis of randomized control trials.

BACKGROUND: Although surgery is the gold standard treatment for anal fissure, the main concern remains its side effects and complications. Botulinum toxin injection and lateral internal sphincterotomy are technical options for patients suffering from chronic anal fissure. However, little is known about the efficacy of these two techniques. The aim of this meta-analysis was to compare the outcomes of botulinum toxin injection versus lateral internal sphincterotomy for chronic anal fissure. METHODS: Original studies in English were searched from the MEDLINE database, PubMed, Web of Science, and the Cochrane Library database. Randomized control trials that compared botulinum toxin injection with lateral internal sphincterotomy were identified. Data were independently extracted for each study, and a meta-analysis was performed using fixed and random effects models. RESULTS: Four hundred and eighty-nine patients from seven trials met the inclusion criteria. Patients undergoing lateral internal sphincterotomy had a higher-healing and incontinence rate. No statistically significant differences were noted in total complications between botulinum toxin injection and lateral internal sphincterotomy. Patients treated with lateral internal sphincterotomy had a significantly lower recurrence rate than the patients treated with botulinum toxin injection. CONCLUSIONS: Our meta-analysis shows that lateral internal sphincterotomy was superior to botulinum toxin injection in terms of healing rate and lower recurrence rate. Botox, however, is safe associated with a lower rate of incontinence and could be used in certain situations. Further studies with a long-term follow-up are required to confirm our observations.

[Play the "combo fist" in the diagnosis and treatment of advanced gastric cancer].

The incidence of gastric cancer ranks fifth among malignant tumors worldwide, with the fourth highest mortality rate. A noteworthy characteristic of our country is the high prevalence of advanced-stage patients of approximately 40%. Advanced-stage gastric cancer carries an unfavorable prognosis with median survival of around one year. Diagnosis methods for advanced-stage gastric cancer (such as laparoscopic exploration, molecular profiling, and artificial intelligence) are still being continuously improved, while chemotherapy remains the primary treatment. With the rapid development of medical science, the role of surgical intervention in advanced-stage gastric cancer is becoming increasingly prominent. Therefore, as gastric tumor surgeons, we should consider how to use a combination of treatments, including surgery, chemotherapy, targeted therapy, immunotherapy, and interventional therapy, based on different pathological stages and the heterogeneity of tumors. With a multidisciplinary approach involving experts from various fields, we can collectively improve the survival rate and quality of life for advanced-stage patients. This article provides a brief overview of the current advances in the diagnosis and treatment of advanced-stage gastric cancer, and discusses therapeutic decision primarily from the perspective of surgeons.

[Application progress of clinical outcome assessment measures in patients with gastric cancer].

Gastric cancer is a common tumor of the gastrointestinal tract, and the global trend in morbidity and mortality are not encouraging. Especially in advanced gastric cancer, patient survival outcome is an essential clinical concern and a vital outcome indicator in clinical outcome assessment. This article reviews the definition of clinical outcome assessment and the measurement tools that can be applied in gastric cancer patients, describes the detailed classification of clinical outcome assessment tools, and reviews the current status of the application of clinical outcome assessment in gastric cancer, analyzing the effects and shortcomings of its application, to provide a reference for the clinical staff in choosing the appropriate tools, and assisting in the comprehensive and holistic assessment of clinical outcomes for the promotion of the development of precision medicine.

[Interpretation of Chinese expert consensus on prevention and treatment of complications related to digestive tract reconstruction after laparoscopic radical gastrectomy for gastric cancer (2022 edition)].

Gastric cancer is one of the most common gastrointestinal malignancies in China. D2 radical gastrectomy is the main treatment for advanced gastric cancer patients. With the advancement of laparoscopic technology, laparoscopic radical gastrectomy has been gradually developed in the world, and even popularized in China. There have been a lot of literature reports on the indications, the scope of lymph node dissection and the improvement of techniques of laparoscopic radical gastrectomy for gastric cancer. Relevant guidelines or consensus for radical gastrectomy. The prevention and treatment of complications of gastrointestinal reconstruction for laparoscopic radical gastric cancer surgery is a major concern for gastrointestinal surgeons. Once complications occur in digestive tract reconstruction, it would increase the hospitalization cost, prolong the hospitalization stay of patients, delay follow-up chemotherapy, and even lead to postoperative death or other serious consequences. Therefore, it is of positive and far-reaching clinical significance to pay attention to the techniques of gastrointestinal reconstruction after laparoscopic radical gastric cancer surgery, to reduce the occurrence of gastrointestinal reconstruction complications, and to detect and reasonably manage related complications in a timely manner. The Chinese expert consensus on prevention and treatment of complications related to digestive tract reconstruction after laparoscopic radical gastrectomy for gastric cancer (2022 edition) has significance value for reducing the occurrence of gastrointestinal reconstruction complications. This manuscript mainly serves as the interpretation and supplement of this Consensus.

[Modified mattress inversion suturing with double barbed sutures used for totally laparoscopic esophagojejunostomy overlap anastomosis after radical total gastrectomy].

Objective: To explore the advantages and safety of a modified mattress inversion suturing using double barbed sutures compared with the traditional overlap method in totally laparoscopic esophagojejunostomy overlap anastomosis. Methods: A retrospective cohort study was conducted. The inclusion criteria were as follows: (1) patients were aged 18 - 80 years old; (2) adenocarcinoma was preoperatively confirmed by pathological analysis; (3) patients had undergone a complete laparoscopic radical total gastrectomy; (4) patients had undergone esophagojejunostomy using the overlap method; (5) patients received a grade of I-III on the American Society of Anesthesiologists physical status classification system; (6) patients' complete follow-up data had been collected. Patients with a history of other malignant tumors, multi-origin tumors, emergency surgery, non-R0 radical resection or distant metastasis were excluded. The clinical data of 89 gastric cancer patients who underwent total laparoscopic radical total gastrectomy in the Department of Gastrointestinal Surgery in the Sixth Affiliated Hospital of Sun Yat-sen University from January 2019 to December 2020 were collected. These patients were grouped according to the esophagojejunostomy method used. Of 89 patients, 32 received modified mattress inversion suturing with double barbed sutures to close the common opening of esophagojejunostomy (the modified anastomosis group), while 57 received traditional overlap anastomosis in which the common opening was closed by barbed suture (the traditional anastomosis group). The operation conditions (incision length, conversion to laparotomy, duration of esophagojejunostomy) and postoperative recovery (time to commencement of a liquid diet, duration of postoperative hospital stay, anastomotic leakage, anastomotic stenosis, and anastomotic bleeding) were compared between the two groups. Results: There was no significant difference in the baseline data of the two groups for any parameter (all P>0.05). All patients received complete laparoscopic radical gastrectomy without conversion to laparotomy. There were no significant differences in the length of the median incision, the proportion of food intake on the first day after surgery, or in the incidence of anastomotic complications such as anastomotic leakage, anastomotic stenosis, and anastomotic bleeding between the two groups (P>0.05). Compared with the traditional anastomosis group, patients in the modified anastomosis group had shorter anastomosis time [26 (19-62) minutes vs. 36 (20-50) minutes, Z=-2.546, P=0.011] and postoperative hospital stay [7 (6-12) days vs. 9 (7-42) days, Z=-4.202, P<0.001]. The differences were statistically significant (all P<0.05). In a subgroup analysis of tumor TNM stage III, Siewert type II and neoadjuvant chemotherapy patients, there was no significant difference in the incidence of anastomotic complications between the modified group and the traditional group. However, the postoperative hospital stay duration in the modified anastomosis group was less than in the traditional anastomosis group. The duration of anastomosis in Siewert type II patients was also shorter in the modified anastomosis group than in the traditional anastomosis group [26 (19-62) minutes vs. 38 (21-50) minutes, Z=-2.105, P=0.035], and the difference was statistically significant (all P<0.05). Conclusion: Complete laparoscopic esophagojejunostomy using modified mattress inversion suturing with double barbed sutures is a safe and feasible anastomosis method to close the common opening of esophagojejunostomy, with shorter operation time, faster postoperative recovery and shorter hospital stay than the traditional method.

Group velocity manipulation in active fibers using mutually modulated cross-gain modulation: from ultraslow to superluminal propagation.

We propose and experimentally demonstrate the propagation of slow/fast light in an erbium-doped fiber (EDF) using mutually modulated cross-gain modulation. The group velocity of the light signal can be manipulated by the effect of gain cross-saturation modulation by a saturating light at an arbitrary wavelength in the gain bandwidth of the EDF. The ultraslow propagation with a small group velocity of 5.6 × 10⁻³c (c is the light speed in free space) and superluminal propagation with a negative group velocity of -1.1 × 10⁻³c has been observed under different modulation phases.

Crossbreeding of Phyllostachys species (Poaceae) and identification of their hybrids using ISSR markers.

Crossbreeding is an efficient means to increase production and quality in plants; however, hybridization is seldom reported in bamboo. We crossbred two bamboo species Phyllostachys kwangsiensis (female parent) and Phyllostachys bambusoides (male parent) for the first time, and obtained suspected bamboo hybrids. We identified two bamboo hybrids from the above parents using PCR/ISSR. We concluded that ISSR markers are useful to identify bamboo hybrids, and that breeding between bamboo species is possible and useful.

[Treatment strategy for gastrointestinal tumor under the outbreak of novel coronavirus pneumonia in China].

The outbreak of the novel coronavirus pneumonia (NCP) has become a public health emergency in China. Chinese authorities and health agencies had devoted great efforts to control this disease. As surgeons specialized in the treatment of gastrointestinal tumors, we should always be aware of the prevention for NCP and incorporate this awareness into every detail of clinical practice. For the patients with gastrointestinal tumors, pre-admission screening should be done in order to rule out NCP. Real-time RT-PCR panel and chest CT scan should be conducted for patients with fever (>37.3℃), travel history to Hubei Province within 14 days, or contact history with residents from Wuhan district within 14 days. Prevention measures for both medical staffs and the screen-negative admitted patients should also be enhanced because false negative is possible. Medical instruments should be properly discarded or disinfected according to standardized procedures established by the local center for disease control and prevention (CDC). Surgical operation should be reduced at a minimal level to prevent cross infection in this special period.Surgical intervention for benign tumor should be postponed. For malignant tumor, multidisciplinary therapy (MDT) is recommended and non-surgical anti-tumor therapy should be selected with higher priority. Neoadjuvant therapy is highly recommended for gastrointestinal cancer at advanced stages that meet the indications of NCCN guideline (gastric cancer T stage ≥ 2/rectal cancer T stage ≥ 3/unresectable colon cancer). Gastric or esophagogastricjunction (EGJ) malignant tumor with obstruction can be managed with gastric tube decompression or stent placement to relieve the symptoms. Transnasal enteral feeding tube intubation/percutaneous endoscopic gastrostomy could be adopted to ensure enteral nutrition supply. For colorectal malignancy with simple intestinal obstruction, stent placement can achieve a high success rate, which not only helps avoid emergency surgery, but also creates a better condition for subsequent surgery. Transcatheter arterial embolization for hemostasis is an alternative choice for gastrointestinal tumor with bleeding. However, emergency operation still must be performed for patients with acute uncontrolled bleeding, obstruction or after other alternative treatment measures fail. All cases with suspicious or confirmed with NCP must be reported to the local CDC department. All invasive intervention must be performed in a designated isolation area. Tertiary prevention measure must be adopted for all anesthetists with additional face mask or medical goggle protection to prevent respiratory droplet transmission. Preventive enterostomy is preferable in lower digestive tract surgery. Thoroughly disinfecting the operating room after surgery is necessary. Fever after surgery must be carefully differentiated whether it's caused by post-surgery abdominal infection/inflammation or NCP. Single-room isolation and related examinations should be performed according to the standard procedures. We believe that with the unprecedentedly joint efforts of doctors and patients, we will eventually win this war against NCP.

Methamphetamine enhances Hepatitis C virus replication in human hepatocytes.

Very little is known about the interactions between hepatitis C virus (HCV) and methamphetamine, which is a highly abused psychostimulant and a known risk factor for human immunodeficiency virus (HIV)/HCV infection. This study examined whether methamphetamine has the ability to inhibit innate immunity in the host cells, facilitating HCV replication in human hepatocytes. Methamphetamine inhibited intracellular interferon alpha expression in human hepatocytes, which was associated with the increase in HCV replication. In addition, methamphetamine also compromised the anti-HCV effect of recombinant interferon alpha. Further investigation of mechanism(s) responsible for the methamphetamine action revealed that methamphetamine was able to inhibit the expression of the signal transducer and activator of transcription 1, a key modulator in interferon-mediated immune and biological responses. Methamphetamine also down-regulated the expression of interferon regulatory factor-5, a crucial transcriptional factor that activates the interferon pathway. These in vitro findings that methamphetamine compromises interferon alpha-mediated innate immunity against HCV infection indicate that methamphetamine may have a cofactor role in the immunopathogenesis of HCV disease.

Multicompartmental analysis of the kinetics of radioiodinated monoclonal antibody in patients with cancer.

A conceptual biologic model was developed and used to analyze the behavior of 123I-Lym-1 monoclonal antibody against African human B cell lymphoma in patients with B cell lymphoma. Originally, the observed data could not be simulated with parameters for homologous immunoglobulins reported in the literature because of a major processor that was capable of distinguishing this murine immunoglobulin from the patient's own immunoglobulins. With a nonlinear parametric model, the data observed in patients could be fitted to the model. The nonlinear parameter determined the transfer of antibody from the intravascular to a processor compartment, primarily the liver. This transfer was a function of the number of free receptors in the processor. Model simulated curves for the time course of concentration of antibody in the blood for different amounts of injected antibody revealed that blood clearance of radiolabeled antibody was profoundly decreased by increased amount of injected antibody. This model provides an explanation for the observations that tumor imaging is improved with injection of larger amounts of antibody, and a basis for modifying the pharmacokinetic behavior of an antibody in order to optimize radioimmunodiagnosis and radioimmunotherapy.

Treatment of a patient with B cell lymphoma by I-131 LYM-1 monoclonal antibodies.

A patient with Richter's syndrome, a malignant lymphomatous transformation of chronic lymphocytic leukemia, had become moribund with rapidly enlarging masses, granulocytopenia and thrombocytopenia despite the use of conventional chemotherapy and radiotherapy. Greater than ten percent of a test dose of I-131 Lym-1, a murine monoclonal antibody produced against Burkitt's African B cell lymphoma, was accumulated by her tumor. The patient was subsequently treated with a series of injections of I-131 Lym-1 with dramatic clinical response, reduction of tumor volume by x-ray computerized tomography and progression of circulating cellular elements toward normality. Her course over the next ten months was not like that to be expected for Richter's syndrome, which has an average survival of four months. This mode of treatment appears promising.

Non-dehalogenation mechanisms for excretion of radioiodine after administration of labeled antibodies.

In patients or mice with cancer the pharmacokinetic behavior of radioiodinated and radiometal chelated antibodies has been observed to be different. Rapid clearance from the tissues and excretion into the urine can occur after injection of radioiodinated antibodies. These observations have been interpreted to reflect in vivo dehalogenation of the antibody. This publication describes a variety of other mechanisms that can underlie these phenomena. These mechanisms include receptor uptake and catabolism of antibody and instability of the labeled antibody due to the labeling conditions. Specifically, the relative masses of chloramine-T and antibody in the iodination reaction mixture, the level of iodination of the antibody, and the amount of antibody administered to the recipient are all factors which can influence the clearance of radioiodinated antibody from the recipient. The final determinant for the different behavior of radioiodinated and In-111 metal chelated antibody relate to the different biologic pathways of indium when compared to iodine.

Surface characteristics of Bacillus cereus and its adhesion to stainless steel.

The ability of a Bacillus cereus strain, isolated from spoiled milk, to adhere to the surface of stainless steel chips was evaluated during its growth in diluted tryptic soy broth (DTSB). The number of cells that adhered to the surface increased markedly as the culture reached the end of the log phase and entered stationary phase, and continued to increase with further incubation. The surface properties of cells from the log, stationary, and late stationary phases were measured by hydrophobic interaction chromatography (HIC) and electrostatic interaction chromatography (ESIC). It was found that surface hydrophobicity of B. cereus vegetative cells from the late stationary phase was the highest followed by those from the stationary phase and the log phase cultures. While the vegetative cells prepared from stationary phase and log phase cultures, respectively, had the highest and the lowest surface charges. Adhesion of B. cereus vegetative cells to stainless steel was positively correlated with the cell surface hydrophobicity (R = 0.979). Surface hydrophobicity and surface positive charge noted on the spores harvested from diluted tryptic soy agar (DTSA) and Mn2+-tryptone glucose extract agar were higher than those harvested from the sucrose or lactose-added DTSA. A wide variation in the surface charge values was noted on the surface of various spores prepared from cultures grown on the four different media tested, while their ability to adhere to stainless steel chips in phosphate buffered saline (PBS) showed no significant difference (p > 0.05). Similarly, the number of spores or vegetative cells adhering to stainless steel suspended in PBS, milk or diluted milk (1000 x) did not differ significantly (p > 0.05).

123I radiolabeling of monoclonal antibodies for in vivo procedures.

When labeled to monoclonal antibodies (MAbs) or their fragments, 123I can be used for imaging or for predicting the treatment potential and radiation dosimetry of 131I labeled to the same molecular species. Because 123I (p,5n) from the Crocker Nuclear Laboratory is in dilute solution, when compared with commercial 125I of labeling grade, we have evaluated labeling parameters using Chloramine-T as the oxidant and derived an optimum set of labeling conditions that provide a 60-80% radiochemical yield of highly immunoreactive antibody. When Lym-1, an IgG-2a murine antibody against human lymphoma, was used, yields of labeled immunoglobulin were decreased by protein or Chloramine-T concentrations less than 0.4 microgram/microliter and 0.8 microgram/microliter, respectively; denaturation of the immunoglobulin occurred when the Chloramine-T concentration was greater than 1.0 microgram/microliter. Optimum labeling occurred at pH 7-8 with deleterious effects when the pH was below 5 or above 10. An optimum method for labeling antibodies with multimillicurie amounts of 123I (less than one iodine atom per 100 antibody molecules) is described. Some of the observations derived from this study are also applicable to the preparation of treatment doses of 131I-labeled antibodies, wherein the amount of antibody can be a restrictive factor.

Molecular epidemiologic analysis of group A rotaviruses in adults and children with diarrhea in Wuhan city, China, 2000-2006.

To compare epidemiologic features and genetic characteristics of group A rotaviruses causing diarrhea in children and adults, a survey was conducted in Wuhan, China, during the period of Dec. 2000-May 2006. A total of 3839 stool specimens from diarrheal patients from eight hospitals were analyzed. Winter seasonality was observed for rotavirus diarrhea in both adults and children, showing overall rotavirus-positive rates of 9.0 and 23.9%, respectively. Throughout the study period, G3 was the most frequent G serotype in both adults and children (detection rates 86.2 and 87.8%, respectively), and was mostly associated with VP4 genotype P[8], VP 6 genotype II (subgroup II), and NSP4 genotype B. G3 rotaviruses were differentiated into eight electropherotypes, among which seven types were found in specimens from both adults and children. VP7 gene sequences of G3 rotaviruses from adults and children (6 and 4 strains, respectively), detected in different years and different hospitals, showed extremely high sequence identities (99-100%) to each other and to a few G3 rotavirus strains reported in Asia. However, lower sequence identities (82-96%) were observed to most of the human and animal G3 rotaviruses reported so far, including some Chinese strains. These findings indicate that in Wuhan, China, epidemic and genetic features of rotaviruses are similar in adults and children, and it has been suggested that G3 rotaviruses that might have originated from the same rotavirus were circulating among children and adults as prevailing viruses. In this study, two rotavirus strains, G9P[8] strain L169, derived from an adult, and G4P[6] strain R479, derived from a child, were isolated and genetically analyzed. The VP7 gene of L169 belongs to a major lineage of G9 rotaviruses that are globally widespread, but is distinct from G9 rotaviruses reported previously in China. The strain R479 had a VP7 gene which was divergent from most G4 human rotaviruses and showed an unusual dual subgroup specificity, I + II. The R479 VP6 gene does not belong to the main clusters of subgroup I and II rotaviruses phylogenetically, but is related to those of the porcine rotaviruses and some unusual human rotaviruses represented by the RMC321 strain isolated in eastern India.

Pharmaceutical quality control of radiolabeled monoclonal antibodies and their fragments.

Monoclonal antibodies are immunochemical reagents whose functional integrity is critical to their clinical applications. Quality control through each stage from antibody production through purification and radiolabeling is necessary if radiopharmaceuticals with reproducible in vivo characteristics are to be achieved. This article describes some of the quality control methods that can be used during developmental and clinical stages of evolution of these radiopharmaceuticals.

Immunochemical aspects of monoclonal antibodies important for radiopharmaceutical development.

Successful development of radiopharmaceuticals from monoclonal antibodies will require the control of several immunochemical aspects of the antibody molecules. A proposed set of methods is presented here for evaluating these immunochemical parameters. This approach consists of monitoring each monoclonal antibody harvest by selective affinity chromatography to determine the presence of detectable alterations in molecular homogeneity. The products are then evaluated by radioimmunoassay technique standardized for total immunoglobulin immunoreactivity. These assays are utilized to detect variation in the immunoreactivity secondary to changes in the hybridoma cell lines, and to measure any detectable denaturation secondary to purification, fragment production and radiolabeling. HPLC molecular sieving chromatography is presented as a practical and informative monitor of molecular stability of these radiopharmaceuticals in vitro and in vivo.