The anti-proliferative effects of nicotinamide and 3-aminobenzamide on human smooth muscle cells in vitro

The proliferation of cultured human arterial smooth muscle cells (HASMC) was suppressed by nicotinamide and its analogue, 3-aminobenzamide, in a concentration-dependent manner, based on cell count and [3H]thymidine incorporation into DNA. The addition of 10 and 15 mM nicotinamide, or 6 mM 3-aminobenzamide, to HASMC, for 96 h, resulted in a 19.3%, 44% and 41.5% reduction of cell growth and inhibition of DNA synthesis. Since c-myc protooncogene expression has previously been correlated with cell proliferation, the steady state level of its mRNA was determined in control and treated HSMC by Northern analysis, following a 1 h treatment with the respective chemicals. Whereas c-myc mRNA was suppressed by nicotinamide in proportion to its ability to reduce HASMC growth, down regulation of c-myc by 3-aminobenzamide was much less than the observed antiproliferative effect. These results suggest that the growth regulatory properties of nicotinamide and 3-aminobenzamide in HASMC are probably unrelated to their activity in controlling c-myc gene expression.

[Identification of a mutation hotspot in exon 8 of Wilson's disease gene by cycle sequencing]

OBJECTIVE

To screen for mutation hotspot of Wilson's disease (WD) gene in Chinese.

METHODS

Cycle sequencing was used to detect mutation in exon 8 of WD gene in 30 patients with WD.

RESULTS

The same missense mutation, Arg778Leu, was identified in 14 WD patients, four of which were homozygous and the others were heterozygous for this mutation. The frequency of this mutation was 30%.

CONCLUSION

The codon 778(CGG-->CTG) of exon 8 in WD gene was one of mutation hotspots in Chinese.

Interleukin-3 gene expression in irradiated mouse bone marrow

The expression of endogenous interleukin-3 (IL-3) gene in mouse bone marrow after whole body irradiation was assessed by immunocytochemistry, in situ hybridization (ISH), and in situ reverse transcription PCR (IS RT-PCR). The results showed obvious injury to the bone marrow followed by recovery 4 weeks after radiation. IL-3 protein was increased in the cytoplasm of recovering hematopoietic cells, especially at 21 days after radiation, while the mRNA was negative, except at 15 days when the mRNA was weakly positive by ISH. IS RT-PCR showed that IL-3 mRNA was strongly positive in the cytoplasm of recovering hematopoietic cells, especially at 10 to 15 days after radiation. We postulate that endogenous IL-3 gene may accelerate hematopoietic recovery in irradiated bone marrow and that IS RT-PCR may objectively report the regulation of IL-3 gene expression.

Analysis of thymoma excision in patients with myasthenia gravis

OBJECTIVE

To study the clinical characteristics of myasthenia gravis (MG) with thymoma and the effect of tracheostomy at the early stage after operation.

METHODS

Thymoma excision and selective tracheostomy were performed on 46 patients with MG from March 1983 to December 1994.

RESULTS

There were 15 patients with benign thymomas and 31 patients with malignant thymomas. MG crises were seen in 52.2% of patients postoperatively, most in type IIb and III. The mortality of in-patients after operation was 10.9%. Thirty-nine patients with thymoma were followed up for 6 months to 12 years after being discharged from hospital. The MG symptoms were relieved in 33.3%, improved in 20.5% and unchanged in 2.6% of patients. 38.5% of patients died of the disease.

CONCLUSION

The characteristics of MG with thymoma are, more severe condition of the patient, rapid advance, and more MG crises before and after operation. The perioperative mortality from MG with thymoma is higher and its prognosis is unfavourable. It is very important to treat severe cases of MG with thymoma by tracheostomy with thymoma excision at the early stage after the operation. This is an effective method to prevent and treat MG crises as well as to lower the perioperative mortality.

Latex rubber (Penrose drain) is detrimental to esophagogastric anastomotic healing in rats

BACKGROUND

Surgeons commonly drain cervical esophagogastric anastomoses, but there is little objective evidence to support this practice. Studies in other areas of gastrointestinal surgery have shown that routine drainage is unnecessary, and even detrimental to anastomotic healing. We conducted an animal experiment to see if a drain had a negative effect on esophagogastric anastomotic healing.

METHODS

Esophagogastric anastomoses were done in 40 rats. In the experimental group (20 rats) a portion of latex rubber Penrose drain was placed over the anastomosis. This was not done in the control group (20 rats). Rats were sacrificed 7 days after surgery. The anastomoses were inspected for leaks, distracted in a tensiometer to measure breaking strength, and subjected to hydroxyproline analysis (an indicator of wound collagen).

RESULTS

There were 4 contained leaks in the experimental group (drain) and no leaks in the control rats (p=0.033). Anastomotic breaking strength was 3.80+/-0.81 N in the experimental rats and 3.46+/-0.64 N in the control rats (p=0.18, not significant). Anastomotic tissue hydroxyproline concentration was 615.9+/-52 nmol/mg in the experimental rats and 609.4+/-195 nmol/mg in the control rats (p=0.13, not significant).

CONCLUSIONS

The presence of drain material predisposed to esophagogastric anastomotic leakage in this rat model.

Gamma-ray-induced cell killing and chromosome abnormalities in the bone marrow of p53-deficient mice

Resistance to the lethal effects of ionizing radiation has been demonstrated in a wide variety of cell types with defects in the p53 gene (thymocytes, splenic B and T cells, in vitro hemopoietic colony-forming cells and intestinal cells of the mouse, embryo cells of the rat, and human Burkitt's lymphoma cells). In contrast, Slichenmeyer et al. (Cancer Res. 53, 4164-4167, 1993) found no evidence of resistance in fibroblasts derived from p53 null mice. The aim of our study was to compare the radiation response of hemopoietic colony-forming cells (in vitro CFC) and of fibroblastoid colony-forming cells or units (CFU-F) within the same tissue (marrow) in p53 null mice (-/-), heterozygotes (+/-) and wild-type animals (+/+). We have also tested the hypothesis that, in proliferating cells, radiation-induced cell killing is mediated through chromosome damage by examining the relationship between these end points in hemopoietic cells of the three mouse types. Both in vitro CFC and CFU-F of -/- mice were resistant to cell killing compared with +/+ and +/- mice whose cellular sensitivities were indistinguishable. The resistance was characterized by a broader "shoulder" on the cell survival curve, i.e. a higher extrapolation number but similar D0 values using the multitarget model or a lower alpha coefficient using the linear-quadratic model. The frequency of chromosomally abnormal marrow cells after irradiation was similar for the three genotypes. However, marrow cells with aberrations carried more aberrations in -/- mice than in +/+ or +/- mice such that the total number of aberrations per 100 cells was higher in -/- mice. Since there were no differences in the yields of aberrations between genotypes in spleen lymphocytes or in CFU-F (both noncycling at the time of irradiation) and less mitotic inhibition in -/- marrow cells than in +/+ or +/- cells, the chromosomal radiosensitivity of -/- marrow hemopoietic cells might be related to reduced cell cycle delay allowing insufficient time for repair, but other explanations have been considered. We postulate that the radiation resistance of both hemopoietic CFC and CFU-F in -/- mice is a consequence of the failure of DNA/chromosome damage to trigger apoptosis or permanent cell cycle arrest to the same extent as in the +/+ or +/- mice: hence the lack of correlation between chromosome damage and cell death in the three mouse types.

[Application of serology and 14C-urea breath test to monitoring of the effect of anti-Helicobacter pylori chemotheraphy]

In order to evaluate the value of serology and 14C-urea breath test in monitoring the effect of anti-Helicobacter pylori chemotherapy, at the first stage of this study, endoscopy, 14C-urea breath test and serology (H. pylori IgG antibody measured by ELISA) were performed in 42 of patients before the onset of anti-H pylori chemotherapy and at 1, 3, 6 and 12 months after termination of the treatment. On analyzing the change of the results of breath test and serology during the one year follow-up period in these patients, "above the cutoff value" in breath test and "reduction of A value less than 15% when comparing with pretreatment" in serology were made as the H. pylori positive criteria for monitoring therapeutic effectiveness on H. pylori. At the second stage of this study, total of another 63 of patients were studied to test the accuracy of the monitoring criteria. The results showed that the sensitivity of breath test was all 100.0% and specificity 95.5% and 100.0% respectively at 6 and 12 month after termination of treatment, the sensitivity of serology was all 100.0% and specificity was 50.0% and 83.3% respectively. A scheme for monitoring the effect of anti-H. pylori chemotherapy by combination of 14C-urea breath test and serology is proposed based on this study.

[Prevalence of cag A and vac A subtypes of Helicobacter pylori in Guangzhou]

OBJECTIVE

To investigate the prevalence of cytotoxin associated gene (cag A) and vacuolating cytotoxin gene (vac A) subtypes of Helicobacter pylori (Hp) from patients with upper gastrointestinal diseases in Guangzhou, and to assess the relationship between cag A, vac A subtypes and Hp related gastrointestinal diseases.

METHODS

191 Hp strains were isolated from patients with different gastrointestinal diseases in Guangzhou. Bacterial DNA from all these strains was extracted. cag A and vac A alleles were typed using PCR with specific primers.

RESULTS

In Guangzhou, Hp cag A positive rate was 85.3% (163/191). cag A positive rate was significantly higher in gastric cancer and peptic ulcer than that in chronic gastritis (P < 0.05). There were six vac A mosaicisms, including 168 for s1a/m2 (88.0%), 14 for s1a/m1b (7.3%), 6 for s1b/m2 (3.1%), 1 for s1b/m1b (0.5%), 1 for s2/m2 (0.5%) and 1 for s1a/m1b-m2 (0.5%). The rate of vac A s1a/m2 subtype in chronic gastritis, peptic ulcer and gastric carcinomas was 87.5% (70/80), 87.5% (84/96) and 93.3% (14/15) respectively. There was no significant relationship between cag A and vac A subtypes (P > 0.05).

CONCLUSION

cag A(+) and vac A s1a/m2 subtype of Hp is predominant in patients with upper gastrointestinal diseases in Guangzhou, cag A(+) strains are further more common in patients with gastric cancer and peptic ulcer.

Observation of the anomalous increase of the longitudinal energy spread in a space-charge-dominated electron beam

We report a new experimental study of the growth of longitudinal energy spread in a space-charge-dominated electron beam, with a beam energy of several keV and beam current of approximately 100 mA. At relatively low beam densities, we measure growing energy spreads with distance along the transport channel, which are in remarkably good agreement with the theory of energy relaxation via Coulomb collisions. At higher beam densities, however, anomalous energy spreads exceeding the predictions of the relaxation theory are observed, which, we believe, could be caused by collective longitudinal-transverse instabilities observed in computer simulation studies. The onset of these instabilities occurs after several plasma periods according to calculations.

Morphological study of the hoof in yak

The fore- and hindlimb of yak have been studied by the gross anatomical methods and standard histological techniques. The artery of ungula was also determined by X-ray and acrylonitrile-butadiene-styrene casting. Anatomical features of the forelimb of yak resemble those of hindlimb, including hoof periphery, hoof coronal, hoof wall, hoof sole, and hoof sphere. The forelimb and hindlimb are almost the same in histological structure. The epidermis comprised all 5 strata: stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum and stratum basale. The papillary layers and dermal lamellae contained a variable amount of capillary as well as collagen and elastic fibres. Many venules and arteriovenous anastomosis were distributed among the reticular layer. Subcutaneous tissue was composed of rich adipose and connective tissue in hoof periphery, hoof coronal, and, especially, hoof sphere. Major arteria in forelimb of yak include arteria digitalis palmaris communis III and arteriae digitales palmares propriae III and IV axialis. Those in hindlimb include arteria digitalis plantaris communis III and arteria digitalis plantaris propria III and IV axialis. Our findings highlight the main morphological features of yak and provide a morphological basis useful to researchers using yak hoof.

[Risk factors related to HIV new infections among men who have sex with men in a cohort study]

Objectives: To analyze and understand the risk factors related to HIV new infections among men who have sex with men (MSM). Methods: A longitudinal observational study among MSM was conducted to collect information on HIV related behaviors and sero-conversion. Univariate and multivariate generalized estimating equations (GEE) were used to discuss the risk factors for HIV new infection. Results: A total number of 4 305 MSM were followed during 2013-2015. Among those self-reported MSM who are seeking partners on the Interner tended to have higher proportion on receptive anal intercourse and consistent condom use during anal intercourse than the subgroups seeking their partners in gay bars or bathrooms. HIV incidence among followed MSM during the study period appeared as 4.3/100 person years, with adjusted RR (aRR) of HIV infection for receptive anal intercourse as group 2.20 (95% CI: 1.49-3.24) times than that of insertion anal intercourse group. Those who used rush-poppers (aRR=1.55, 95% CI: 1.10-2.17), unprotected anal intercourse (aRR=2.24, 95%CI: 1.62-3.08), and those with syphilis infection (aRR=2.95, 95%CI: 2.00-4.35) were also risk factors for HIV new infections. After controlling other factors, the relationship between the ways of seeking partners and HIV new infection was not statistical significant. Conclusion: Risk factors for HIV new infection among MSM appeared complex and interactive, suggesting that further studies are needed to generate tailored strategies for the prevention of HIV epidemic among MSM population.

[Pathogenic characteristics and influence factors of bloodstream infection-induced severe sepsis in pediatric intensive care unit]

Objective: To summarize the pathogenic characteristics of bloodstream infection (BSI)-induced severe sepsis and analyze the influence factors in pediatric intensive care unit (PICU). Methods: Pediatric patients who were diagnosed with severe sepsis caused by BSI in the PICU of Children's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2016 to December 2021 were retrospectively selected and divided into survival group and death group according to their discharge outcomes. Clinical characteristics, laboratory parameters, pathogenic characteristics and drug resistance of the patients were collected. The characteristics of pathogens, clinical and laboratory indicators were summarized, and the influencing factors of death in children with severe sepsis caused by BSI were analyzed based on binary multivariate logistic regression. Results: A total of 132 patients, aged [M (Q1, Q3)] 36 (10, 119) months, with BSI-induced severe sepsis were enrolled in this study, including 81 males and 51 females. There were 38 cases aged 36 (15, 120) months in the death group, including 23 males and 15 females. There were 94 cases, aged 36 (8, 108) months, in the survival group, including 58 males and 36 females. A total of 132 strains of pathogens were isolated, including 87 strains (65.9%) of Gram-negative bacteria. The top 5 pathogens were Klebsiella pneumoniae (24 cases, 18.2%), Escherichia coli (17 cases, 12.9%), Acinetobacter baumannii (13 cases, 9.8%), Pseudomonas aeruginosa (10 cases, 7.6%) and Staphylococcus aureus (10 cases, 7.6%). The proportion of multi-drug resistant bacteria in hospital-acquired BSI was higher than that in community-acquired BSI [52.9% (36/68) vs 15.6% (10/64), P=0.001]. The proportions of community-acquired infection were 58.5% (55/94) and 23.7% (9/38) in the survival and death groups, respectively, the difference was statistically significant (P<0.001). The proportion of central venous catheter insertion before bloodstream infection in the death group was higher than that in the survival group [63.2% (24/38) vs 42.6% (40/94), P=0.034]. According to the binary multivariate logistic regression analysis, hospital-acquired infection (OR=4.80, 95%CI: 1.825-12.621, P=0.001), absolute neutrophil count (ANC) (OR=0.93, 95%CI: 0.863-0.993, P=0.030) and decreased albumin (OR=0.89, 95%CI: 0.817-0.977, P=0.014) were risk factors for death. Conclusions: The common pathogen of BSI-induced severe sepsis in PICU is Gram-negative bacteria. The proportion of multi-drug resistant organisms of BSI obtained in hospitals is high. Children with severe sepsis due to BSI with nosocomial acquired infection, ANC and decreased albumin have a high risk of death.

Primary immunodeficiency in south China: clinical features and a genetic subanalysis of 138 children

OBJECTIVES

We analyzed the clinical features of 138 patients with primary immunodeficiency (PID) and performed genetic testing on a subset of patients in order to complete gaps in research on PID in South China and thus improve pediatricians' ability to recognize and diagnose PID.

METHODS

We performed a retrospective analysis based on the medical records of PID patients hospitalized in our institution between May 1999 and June 2012. Gene sequencing was performed in 59 cases.

RESULTS

Children with PID usually present with fever and repeated infections that generally affect the respiratory and digestive tracts. Growth retardation is observed in some cases. Of the 138 patients, 113 were boys, median age at onset was 5 months (range, 0-119 months), and age at diagnosis was 10 months (2-159 months). A family history of repeated infection or death of family members in infancy because of recurrent infections was recorded in 20 cases (14.49%). Antibody defects were detected in 48 cases (34.78%), combined immunodeficiency disease in 45 cases (32.61%), and other well-defined immunodeficiency syndromes in 45 cases (32.61%). Of the 59 patients from the genetic subanalysis, 24 (15.94%) had a genetic mutation (x-linked agammaglobulinemia, 8 cases; severe combined immunodeficiency, 8 cases; hyperimmunoglobulin M syndrome, 3 cases; hyperimmunoglobulin E syndrome, 3 cases; chronic granulomatous disease, 2 cases). We detected 4 novel mutations. No relevant mutations were found in the remaining 35 cases.After treatment with intravenous immunoglobulin and anti-infectious agents, 16 patients died in hospital, and 5 cases died after discontinuing treatment (mortality, 15.22%).

CONCLUSIONS

In recent years, the number of patients with PID has risen gradually in South China. Genetic testing can confirm diagnosis. Since PID seriously affects children's quality of life, it is important to diagnose, treat, and intervene early.We hope our clinical and genetic analyses of children with PID can provide diagnostic guidance for clinicians.

Thymoquinone protects against cerebral small vessel disease: Role of antioxidant and anti-inflammatory activities

Cerebral small vessel disease (CSVD) is a leading cause of progressive decline of cognition and a major risk factor for stroke. Thymoquinone (TQ) is the major biological component of Nigella sativa (N. sativa) and its extracts. We explored the possible protective effect of TQ against CSVD in strokeprone spontaneously hypertensive SHRsp rats. Morris water maze and novel object recognition tests were conducted to evaluate memory and cognitive function. mRNA expression of inflammatory factors were determined and oxidative stress was evaluated. We showed that TQ markedly decreased the level of systolic blood pressure in SHRsp rats. TQ reduced the escape latency time and the time spent in the target quadrant in the Morris water maze test in SHRsp rats. TQ also decreased the time spent with the novel object in SHRsp rats in both short- and long-term memory tests. TQ markedly increased the capacity to distinguish between familiar objects and novel objects in the SHRsp rats in the short- and long-term memory tests. The mRNA expression of IL-1β, IL-6, monocyte chemoattractant protein-1 and cyclooxygenase-2 in the brain of SHRsp rats was remarkably decreased by TQ, indicating the reduction of inflammation. Moreover, TQ increased the activities of superoxide dismutase and catalase, decreased the malondialdehyde level and increased glutathione level in the brain of SHRsp rats, indicating the attenuation of oxidative stress. In summary, we found that TQ could effectively attenuate the blood pressure and the injury of memory and cognition under the condition of CSVD. The anti-inflammatory and antioxidant activities of TQ may be responsible for its protective effect. We demonstrate that TQ is a novel candidate for the treatment of CSVD and its neurological outcome.

[Epidemiological and Etiologic characteristics of Meningococcal meningitis in Xinjiang Uygur Autonomous Region,1960-2019]

Objective: To understand the epidemiological and etiologic characteristics of meningococcal meningitis in Xinjiang Uygur Autonomous Region (Xinjiang). Methods: The epidemiological data about the meningococcal meningitis cases in Xinjiang from 1960 to 2019 were collected from the China information system for disease control and prevention and the Center for Disease Control and Prevention of Xinjiang. The epidemiological characteristics were analyzed. Clinical specimens from suspected cases were cultured and tested by real-time PCR method. A survey on the carriage rate of Neisseria meningitides (Nm) in the healthy population was performed. The serogroups of isolates were determined by serum-agglutination and PCR methods. Multi-locus sequence typing was used for subtyping the isolates. Results: The incidence rates of meningococcal meningitis in Xinjiang from 1960 to 2019 were 0.02/100 000-81.32/100 000, with the mortality as 1.05%-20.78%. The five districts with the most cases were Kashi prefecture, Aksu prefecture, Urumqi city, Changji Hui autonomous prefecture, and Hotan prefecture. Before 1990, serogroup A (81.82%) was the commonest group for cases and contacts. After 1990, 14.00% of the cases were caused by serogroups B, C, W, and Y. There was no predominant serogroup for contacts with serogroups B, C, W, Y, and C accounting for 23.28%, 18.53%, 15.52%, 9.91% and 7.33% respectively. The general Nm carriage rate was 15.50%, with the population of 16 - 20 years age group having the highest rate (25.53%). Serogroups B (52.11%), W (20.66%), C (12.21%), and Y (9.39%) occupied 52.11%, 20.66%, 12.21% and 9.39% respectively. The commonest clonal lineages of Nm isolates were ST-4821, ST-175, and ST-5 clonal complexes, while the ST-5 and ST-4821 clonal complexes were the major ones for invasive strains. Conclusions: There appeared regional differences in the incidence rates of Xinjiang meningococcal meningitis, and the carriage rate of Nm was high. The serogroups have been changing. It is necessary to strengthen the prevention and control of meningococcal meningitis to prevent any potential outbreak.

[Etiological analysis on a foodborne disease outbreak caused by two serotypes of Salmonella]

Objective: To understand the etiological characteristics of 2 serotypes of Salmonella strains isolated from a foodborne disease outbreak. Methods: A total of 11 anal swabs of the cases, 13 suspected contaminated food and 10 environmental samples were collected from a foodborne disease outbreak occurred on September 8, 2022 in a school. The anal swabs were enriched with selenite brilliant green enrichment broth (SBG) and brain heart infusion broth (BHI) respectively. PCR detection and culture of common intestinal pathogens were carried out. The suspected food samples were tested according to national standards for food safety. Multiple suspected Salmonella colonies were obtained and selected for serotype determination and whole genome sequencing. Serotypes were determined based on the whole-genome sequence, and clustering analysis was performed based on core genome single nucleotide polymorphism (SNP). Results: The positive rates of Salmonella in anal swabs and suspected food samples were 9/11 and 5/13 respectively. Both Salmonella Uganda and Salmonella Idikan were isolated from 4 anal swabs and 4 suspected food samples. For the remaining samples, only Salmonella Uganda or Salmonella Idikan was isolated in each sample. The positive rate of Salmonella in 11 anal swabs of the cases after BHI enrichment for 12 h and 24 h were all 9/11 in real-time PCR, same to the culture results. Salmonella Uganda and Salmonella Idikan formed two independent and genetically distant lineages in the clustering tree based on core genome SNP, and 0-14 and 0-23 SNP were observed in Salmonella Uganda and Salmonella Idikan respectively. Conclusions: This foodborne disease outbreak was probably caused by Salmonella Uganda and Salmonella Idikan, which both exhibited strong genetic diversity. The PCR based pathogen screening strategy plus pathogen enrichment for cases' annal swabs can be used in the routine outbreak investigation.