[A multicenter epidemiological study of acute bacterial meningitis in children]

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.

[Risk factors and resistance patterns of invasive Acinetobacter Baumannii infection in Children]

Objective: To understand the risk factors and antibiotics-resistant patterns of invasive Acinetobacter baumannii infection in Children. Methods: This retrospective study was conducted in 6 tertiary hospitals from January 2016 to December 2018. The basic information, clinical data and the results of antimicrobial susceptibility testing were collected from the 98 pediatric inpatients with Acinetobacter baumannii isolated from blood or cerebrospinal fluid and analyzed. According to the susceptibility of the infected strains to carbapenems, they were divided into carbapenem-sensitive Acinetobacter baumannii (CSAB) group and carbapenem-resistant Acinetobacter baumannii (CRAB) group. According to the possible sources of infection, they were divided into nosocomial infection group and community infection group. Chi-square test or Fisher exact test were used to analyze categorical variables and rank sum test were used to analyze continuous variables. The risk factors of invasive CRAB infection in children were analyzed by Logistic regression. Result: There were 56 males and 42 females in 98 cases. The onset age of patients was 8 (2, 24) months. There were 62 cases (63%) from rural area. A total of 87 cases (89%) were confirmed with bloodstream infection, and 12 cases (12%) confirmed with meningitis (1 case was accompanied with bloodstream infection). In these patients, 66 cases (67%) received invasive medical procedures or surgery, 54 cases (55%) received carbapenems-containing therapy. Twenty-four cases were infected with CRAB, and 74 cases with CSAB. The onset age of cases in CRAB group was lower than that in CSAB group (4 (1, 9) vs. 10 (4, 24) months, Z=-2.16, P=0.031). The proportions of hospitalization in intensive care unit, carbapenem antibiotics using, pneumonia and adverse prognosis in CRAB group were higher than those in CSAB group (6 cases (25%) vs. 4 cases (5%), 18 cases (75%) vs. 36 cases (49%), 17 cases (71%) vs. 17 cases (23%), 6 cases (25%) vs. 4 cases (5%), χ²=5.61, 5.09, 18.32, 5.61, all P<0.05). Seventy-seven cases were nosocomial infection and 21 cases were hospital-acquired infection. The proportion of children hospitalized in high-risk wards for nosocomial infections, length of hospitalization, number of antimicrobial therapy received and duration of antimicrobial therapy were higher in the hospital associated infection group than those in the community acquired infection group (all P<0.05). Logistic regression analysis showed that children from rural area (OR=8.42, 95%CI 1.45-48.88), prior mechanical ventilation (OR=12.62, 95%CI 1.31-121.76), and prior antibiotic therapy (OR=4.90, 95%CI 1.35-17.72) were independent risk factors for CRAB infection. The resistance percentage of CSAB isolates to many classes of antibiotics was <6% except to gentamicin, which was as high as 20% (13/65). All CRAB isolates of resistant to ampicillin-sulbactam (20/20), cefepime (23/23), piperacillin (17/17), meropenem (23/23) and imipenem (24/24) were 100%. The resistance percentage to other antibiotics were up to 42%-96%. Conclusions: Most of invasive Acinetobacter baumannii infection in children in China are hospital-acquired. The outcome of invasive CRAB infection was poorer than that of CSAB infection. The drug resistance rate of CRAB strains isolated is high. Living in rural area, prior invasive mechanical ventilation and prior antibiotic therapy were independent risk factors for invasive CRAB infection. The prevention and control of nosocomial infection and appropriate use of antibiotics to reduce Acinetobacter baumannii infection.

Development of a narrow stopband filter for spectroscopic fast ion deuterium-alpha measurements

A new technique to attenuate the unshifted deuterium Balmer-alpha (D-alpha) emission is developed and tested for the fast ion D-alpha (FIDA) diagnostic. The unshifted D-alpha emission, at λ = 656.1 nm, is around three orders of magnitude higher than the desired FIDA emission. Blocking the strong emission feature is essential to prevent blooming and light smearing on the CCD chip and scattered light contamination. The new method is a notch filter approach that utilizes the reflection from ultra-narrow bandpass filters to block the saturating signal before it enters the spectrometer. Collimated light from the fibers is reflected off the filter at a 15° angle of incidence. Measurements show that a center wavelength transmission of 0.006 and a blocking full width at half maximum of ∼1 nm are achieved by using a 200 μm fiber and a 20 mm focal length collimator with two filters.

Trends and publication rates of abstracts presented at the British Association of Head and Neck Oncologists' (BAHNO) annual meetings: 2009 - 2015

The British Association of Head and Neck Oncologists (BAHNO) hosts an annual meeting at which research from all specialties involved in the management of head and neck oncology is presented. We have analysed the rate of publication of the abstracts presented, and reviewed the finalised programmes from the meetings between 2009 and 2015. The 2014 meeting was excluded as it was a combined international meeting. Key terms were searched in PubMed and Google Scholar to identify publications in peer-reviewed journals. If none was identified, these platforms were searched for the authors' names. Published abstracts were excluded. Study and journal demographic data were extracted. A total of 363 abstracts were presented, including 75 oral, 271 poster, and 17 of unclear presentation method. The total publication rate was 31.1%, representing 46.7% of oral abstracts and 27.3% of poster presentations. The mean time to publication was 16.5 months. Research was published in 45 individual journals with a mean (range) impact factor of 2.559 (0.886-36.418). There was a trend towards an increasing number of presentations over time with a decreasing publication rate. However, there was no trend in mean impact factor by year. The publication rate of abstracts presented at the BAHNO annual meetings is comparable with that of other large otolaryngology and head and neck conferences. The mean impact factor has not previously been utilised within this field, but may prove a useful metric that enables monitoring of the quality of presented research and comparison of the impact of the conferences.

[Risk factors for pulmonary fibrosis in patients with paraquat poisoning]

Objective: To investigate the risk factors for pulmonary fibrosis in patients with paraquat (PQ) poisoning. Methods: A total of 120 patients with PQ poisoning who were admitted from January 2012 to December 2014 were enrolled. According to the presence or absence of pulmonary fibrosis, the patients were divided into non-pulmonary fibrosis group (67 patients) and pulmonary fibrosis group (53 patients) . The Acute Physiology and Chronic Health Evaluation II (APACHE II) score was obtained on days 1 and 3 of poisoning. Routine blood test results, blood biochemical parameters, and radiological parameters were recorded, and the patients with PQ poisoning were followed up for survival and pulmonary fibrosis. Results: A total of 39 patients with PQ poisoning died, resulting in a mortality rate of 32.5%. There were 53 patients who developed pulmonary interstitial fibrosis, yielding an incidence rate of 44.2%. Compared with the non-pulmonary fibrosis group, the pulmonary fibrosis group had a significantly higher age, a significantly higher dose of PQ, and significantly higher APACHE II scores on days 1 and 3 of poisoning (P<0.01) , as well as significantly higher white blood cell (WBC) count and neutrophil count on day 1, significantly higher levels of urea nitrogen, creatinine, and blood glucose on days 1 and 3, and significantly higher activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (P<0.01) . The logistic regression analysis showed that the dose of PQ, WBC count and neutrophil count on day 1, APACHE II scores on days 1 and 3 of poisoning, levels of urea nitrogen, creatinine, and blood glucose, and activities of AST and ALT were associated with the development of pulmonary fibrosis in patients with PQ poisoning. Conclusion: Oral dose of PQ, APACHE II scores on days 1 and 3 of poisoning, levels of urea nitrogen, creatinine, and blood glucose, activities of AST and ALT, and WBC count and neutrophil count on day 1 are risk factors for pulmonary fibrosis in patients with paraquat poisoning.

microRNA-142-3p inhibits apoptosis and inflammation induced by bleomycin through down-regulation of Cox-2 in MLE-12 cells

microRNA (miR)-142-3p is implicated in malignancy and has been identified as a biomarker for aggressive and recurrent lung adenocarcinomas. This study aimed to evaluate the inhibitory effect of miR-142-3p on apoptosis and inflammation induced by bleomycin in MLE-12 cells. MLE-12 cells were first transfected either with miR-142-3p mimic or miR-142-3p inhibitor and then the cells were exposed to 50 μg/mL of bleomycin. Thereafter, cell viability, apoptosis and the expression of pro-inflammatory cytokines were assessed using CCK-8, flow cytometry, RT-PCR and western blot analyses. Cox-2, PI3K, AKT and mTOR expressions were detected by western blotting after bleomycin was administered together with NS-398 (an inhibitor of Cox-2). As a result, cell viability was significantly decreased, as well as apoptosis and the expression of IL-1 and TNF-α were remarkably increased after 50 and 100 μg/mL of bleomycin administration. miR-142-3p overexpression alleviated bleomycin-induced apoptosis and overproduction of these two pro-inflammatory cytokines, while miR-142-3p suppression exhibited completely opposite results. Up-regulation of Cox-2 and inactivation of PI3K/AKT/mTOR were found in bleomycin-pretreated cells, while these abnormal regulations were partially abolished by miR-142-3p overexpression and NS-398. In conclusion, this study demonstrated that miR-142-3p overexpression protected bleomycin-induced injury in lung epithelial MLE-12 cells, possibly via regulating Cox-2 expression and PI3K/AKT/mTOR signaling pathway. These findings provide evidence that miR-142-3p may be a therapeutic strategy for idiopathic pulmonary fibrosis (IPF) treatment.

Expression of survivin and bax/bcl-2 in peroxisome proliferator activated receptor-gamma ligands induces apoptosis on human myeloid leukemia cells in vitro

The present study was undertaken to investigate the mechanisms of peroxisome proliferator activated receptor-gamma (PPAR-gamma) ligand-induced apoptosis on human myeloid leukemia K562 and HL-60 cell lines. The results revealed that both 15-deoxy-delta(12,14)-prostaglandin J2 (15d-PGJ2) and troglitazone (TGZ) have significant anti-proliferation- and apoptosis-inducing effects on these two kinds of leukemia cells. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly using Wright's and Hoechst 33258 staining. Reverse transcription-PCR and western blot analyses demonstrated that both survivin and bcl-2 expression were downregulated markedly, while bax expression was upregulated concurrently when apoptosis occurred. We therefore conclude that 15d-PGJ2 and TGZ have significant apoptosis effects on K562 and HL-60 cells in vitro, and that upregulation of bax as well as downregulation of survivin and bcl-2 expression may be the important apoptosis-inducing mechanisms. The results suggest that PPAR-gamma ligands may serve as potential therapeutic agents for both acute and chronic myeloid leukemia.

Oridonin-induced apoptosis in leukemia K562 cells and its mechanism

Oridonin, an extract from the Chinese herb Rabdosia rubescens, is currently one of the most important traditional Chinese herbal medicines. Recently oridonin has been reported to have anti- tumor effects in a large variety of malignant diseases. In this study, we investigated the apoptotic inducing effect of oridonin in leukemia K562 cells and its mechanism. Cell growth inhibition was measured using a microculture tetrazolium assay, apoptosis was measured by flow cytometry and electron microscopy as well as by DNA fragmentation analysis. Telomerase activity was measured by TRAP-enzyme- linked immunosorbent assay, and the expression of Bcl-2 and Bax proteins was detected by western blot analysis. The results showed that oridonin could inhibit the proliferation and induce apoptosis on leukemia K562 cells remarkably. Telomerase activity as well as Bcl-2 expression was down- regulated, while Bax expression was up-regulated concurrently, when apoptosis ocurred. We therefore conclude that oridonin demonstrated anti-proliferative and apoptosis-inducing effects on K562 cells in vitro, and that changes in bcl-2 and bax protein levels as well as telomerase activity may play an important role in its mechanism of action.

Anti-proliferative Effects of Oridonin on SPC-A-1 Cells and its Mechanism of Action

Oridonin, an extract from the Chinese herb Rabdosia rubescens, is currently one of the most important traditional Chinese herbal medicines. We investigated the anti-proliferative effect of oridonin on the lung cancer cell line SPC-A-1 and its mechanism of action. Growth inhibition was measured using a microculture tetrazolium assay and apoptosis was measured by several standard methods. Western blot analysis measured the expression of bcl-2 and bax proteins. Oridonin (> 28 μmol/l) inhibited the growth of SPC-A-1 cells and induced apoptosis. Marked morphological changes indicative of apoptosis were observed, especially in cells treated with oridonin for 48–60 h. Western blot analysis revealed downregulation of bcl-2 and upregulation of bax proteins following treatment with oridonin for 48 h. We conclude that oridonin demonstrated anti-proliferative and apoptosis-inducing effects on SPC-A-1 cells in vitro, and that changes in bcl-2 and bax protein levels may play an important role in its mechanism of action.

Effect of chromium content on structure and mechanical properties of Ti-7.5Mo-xCr alloys

The present work is a study of a series of Ti-7.5Mo-xCr alloys with the focus on the effect of chromium content on the structure and mechanical properties of the alloys. Experimental results show that low hardness, strength and modulus binary Ti-7.5Mo alloy is comprised primarily of fine, acicular martensitic alpha' phase. When 1 wt % Cr is added, a small amount of beta phase is retained. With 2 wt % or more chromium added, the entire alloy becomes equi-axed beta phase with bcc crystal structure. The average beta grain size decreases with Cr content. When the alloy contains about 2-4 wt % Cr, a metastable omega phase is present. In Ti-7.5Mo-2Cr alloy appears the highest omega intensity accompanied with high microhardness, bending strength and modulus. The omega-induced embrittling effect is most profound in Ti-7.5Mo-2Cr alloy that exhibits a terrace type fracture surface covered with numerous micron-sized dimples. The alloys with higher Cr contents show normal ductile type fractography with much larger deformation dimples. The present results indicate that Ti-7.5Mo-(4-6)Cr alloys seem to be potential candidates for implant application.

Structure and properties of Ti-7.5Mo-xFe alloys

The present work is a study of a series of Ti-7.5Mo-xFe alloys, with the focus on the effect of iron addition on the structure and mechanical properties of the alloys. Experimental results indicate that alpha" phase-dominated binary Ti-7.5Mo alloy exhibited a fine, acicular martensitic structure. When 1 wt% or more iron was added, the entire alloy became equi-axed beta phase structure with a grain size decreasing with increasing iron content. A thermal omega phase was formed in the alloys containing iron of roughly between 0.5 and 3 wt%. The largest quantity of omega phase and highest microhardness were found in Ti-7.5Mo-1Fe alloy. The binary Ti 7.5Mo alloy had a lower microhardness, bending strength and modulus than all iron-containing alloys. The largest bending strength was found in Ti-7.5Mo-2Fe alloy. The present alloys with iron contents of about 2-5 wt% seem to have a great potential for use as an implant material.

Atypical features prompting neuroimaging in acute optic neuropathy in adults

BACKGROUND

Acute optic neuropathy due to an intracranial lesion may masquerade as optic neuritis or nonarteritic anterior ischemic optic neuropathy (NAION). We reviewed the records of patients who presented with acute unilateral optic neuropathy that was initially diagnosed as optic neuritis or NAION but who ultimately proved to have an underlying structural lesion.

METHODS

Retrospective observational case series. We reviewed the records of patients with the initial diagnosis of optic neuritis or NAION in whom the diagnosis was changed to an intracranial etiology at four tertiary care neuro-ophthalmology centres between 1995 and 1998.

RESULTS

Eight cases were identified in which atypical features prompted further investigation, including neuroimaging, leading to the diagnosis of an intracranial etiology for the optic neuropathy. Five patients were discovered to have neoplasms (a tuberculum sellae meningioma in two cases, an optic nerve sheath meningioma in two cases and a metastatic lesion in one case), and three patients had intracranial sarcoidosis. Atypical features for optic neuritis included a progressive course, absence of pain, optic atrophy at presentation, lack of significant visual improvement and age over 40 years. For NAION, the atypical features included progressive course, optic atrophy on presentation, absence of vasculopathic risk factors and preceding transient visual loss.

INTERPRETATION

Clinicians should be aware that patients with intracranial lesions may present with acute optic neuropathy mimicking optic neuritis or NAION and that certain atypical features should warrant consideration for neuroimaging.

[An animal experiment and clinical investigation on the protective effect of selenium on the microcirculation induced by free radical damaged RBCs]

Fluorescent labeling image analysis was used to evaluate the changes in cerebral arteriole and veinlet diameters (D), circulation velocities (FV) and permeability (VP) in rats; while in clinics, a laser-doppler device was used for assessing changes of skins and muscles microcirculation. The results show that in control rats, equal volume perfusion of free radical damaged RBCs resulted in decreases of D and FV significantly but VP was increased, whereas in the case when free radical damaged RBCs were perfused together with selenium, no disturbances in the D and VP were observed with FV even improved. In the human control group, either average skin microcirculative perfusions (ASMP) at 25 degrees C or maximal skin microcirculative perfusions (MSMP) at 42 degrees C were evidently decreased during myocardial ischemia/reperfusion period, while ASMP at 24th hour of post-surgery was kept reducing. At the same time, the changes in muscles microcirculative perfusions (MMP) tended to be similar to the skin, but overloaded than the pre-surgery levels at 24th hour of post-surgery period. In the selenium group before surgery, the ratio of MSMP to ASMP was obviously increased than the control group (3.95 in Se group vs 1.74 in control group, P < 0.05), but did not have significantly differences in ASMP, MSMP and MMP between the two groups during surgery period. RBC deformabilities were not changed. At 24th hour post-surgery, the ASMP were almost restored to pre-surgery levels. However, MMP were still lower than the pre-surgery levels.

CONCLUSIONS

(1) free radical damaged RBC perfusion leads to damage of microcirculation; (2) selenium is highly efficient in protecting microcirculation from free radical damaged RBC disturbance; and (3) Oral administration of selenium may improve pre-surgery maximal skin microcirculative perfusion and promote recovery of the worsened skin microcirculation in addition to prevent the occurrence of RBC deformability.

The high jugular bulb: report of five cases and a review of the literature

The jugular bulb varies widely in position and dimensions. A high jugular bulb is not an uncommon finding in temporal bones. Besides our five cases with different clinical manifestations, we review 52 cases diagnosed clinically and published previously in the English literature. The high jugular bulb occurs more often on the right temporal bone. Certain pathologic conditions, such as an abnormal bone formation, an aberrant sinusojugular system, or decreased pneumatization of the mastoid bone, may predispose an individual to its occurrence. Most people with this anatomical variation remain asymptomatic. However, various otologic problems and symptoms may be attributed to this condition. A high resolution computed tomography scan is the most convenient diagnostic tool at present. Law projection plain mastoid radiography may reveal a high jugular bulb in certain cases, providing a preoperative warning to an otologic surgeon. An exploratory tympanotomy is not suggested for those with a high jugular bulb with a conductive hearing loss, while jugular vein ligation has been reported to have good results in alleviating intractable pulsatile tinnitus. For most asymptomatic patients, regular long-term follow-up is recommended.