[Best evidence summary for awake prone positioning in treating hypoxemic due to COVID-19 infection]

Objective: To retrieve, evaluate, and summarize the best evidence for the treatment of hypoxemia in patients with COVID-19 infection using the awake prone positioning, with the aim of guiding healthcare professionals in the standardized implementation of this therapy. Methods: A systematic search was conducted in databases including UpToDate, BMJ Best Practice, JBI Evidence-Based Healthcare Center, American Association of Critical-Care Nurses, Intensive Care Society, European Respiratory Society, World Health Organization website, Cochrane Library, PubMed, China National Knowledge Infrastructure (CNKI), and Wanfang. The retrieved literature was subjected to quality assessment and evidence extraction. Results: A total of ten publications were included, consisting of one thematic evidence summary, one guideline, two systematic reviews, three randomized controlled trials, and three expert consensus statements. This summary synthesizes thirty key pieces of evidence in five categories: organizational management and training, risk assessment, preparatory operations, implementation key points, and risk control. Conclusions: Awake prone positioning is beneficial for improving hypoxemia in patients with COVID-19 and is easy to implement. Medical institutions should develop nursing management systems, operational standards, and best practices for awake prone positioning based on evidence-based evidence in order to improve the quality of care management for such patients.

TFP5, a Peptide Derived from Cdk5 Activator p35, Protects Pancreatic β Cells from Glucose Toxicity

We studied the effect of TFP5 on MIN6 cells (cultured mouse islet β cells) treated with different concentrations of glucose (5 or 25 mM). The results were verified in C57BL/6J mice (control; n=12) and db/db mice with type 2 diabetes mellitus (n=12). To synthesize TFP5, peptide p5 (a derivative of p35 protein, activator of cyclin-dependent kinase 5, Cdk5) was conjugated with a FITC tag at the N-terminus and an 11-amino acid TAT protein transduction domain at the C-terminus. TFP5 was employed to inhibit Cdk5 activity and then to evaluate its efficiency in treating experimental type 2 diabetes mellitus. TFP5 effectively inhibited the pathological hyperactivity of Cdk5, enhanced insulin secretion, and protected pancreatic β cells from apoptosis in vitro and in vivo. In addition, TFP5 inhibited inflammation in pancreatic islets by reducing the expression of inflammatory cytokines TGF-β1, TNFα, and IL-1β. These novel data indicates that TFP5 is a promising candidate for treatment of type 2 diabetes mellitus.

[Comparison of the predictive value of Padua and the IMPEDE assessment scores for venous thromboembolism in patients with newly diagnosed multiple myeloma: A single institution experience]

Objective: To compare the predictive efficacy of the two thrombosis risk assessment scores (Padua and IMPEDE scores) in venous thromboembolism (VTE) within 6 months in patients with newly diagnosed multiple myeloma (NDMM) in China. Methods: This study reviewed the clinical data of 421 patients with NDMM hospitalized in Beijing Jishuitan Hospital from April 2014 to February 2022. The sensitivity, specificity, accuracy, and Youden index of the two scores were calculated to quantify the thrombus risk assessment of VTE by the Padua and IMPEDE scores. The receiver operating characteristics curves of the two evaluation scores were drawn. Results: The incidence of VTE was 14.73%. The sensitivity, specificity, accuracy, and Youden index of the Padua score were 100%, 0%, 14.7%, and 0% and that of the IMPEDE score was 79%, 44%, 49.2%, and 23%, respectively. The areas under the curve of Padua and IMPEDE risk assessment scores were 0.591 and 0.722, respectively. Conclusion: IMPEDE score is suitable for predicting VTE within 6 months in patients with NDMM.

MRI presentations of Müllerian duct anomalies in association with unilateral renal agenesis

AIM

To evaluate the presentations of Müllerian duct anomalies (MDAs) associated with unilateral renal agenesis (URA) on magnetic resonance imaging (MRI).

MATERIALS AND METHODS

From 2014 to 2021, 92 patients with MDAs coexisting with URA who had undergone MRI were reviewed, and imaging patterns were analysed.

RESULTS

Based on the different imaging patterns, there were 74 cases of Herlyn-Werner-Wunderlich (HWW) syndrome (80.4%), nine cases of unicornuate uterus (10.9%), and nine cases of Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome (8.7%). In HWW syndrome, URA was ipsilateral to the vaginal or cervical obstruction. All the nine cases of unicornuate uterus were obstructive, and the most common subtype was unicornuate uterus with a non-communicating functioning rudimentary horn. The other two cases of unicornuate uterus with no rudimentary horn were obstructed due to cervical os obliteration, one of which was complicated with contralateral absent ovary. URA was contralateral to the unicornuate uterus in all cases. In MRKH syndrome, seven patients had bilateral rudiments and ovaries, all of which were unilaterally or bilaterally located above the pelvic brim, and URA was ipsilateral to the ectopic ovary in all cases. The other two patients had unilateral absent rudiment, ovary, and ipsilateral URA.

CONCLUSIONS

MRI presentations of URA-associated MDAs are diverse, with HWW syndrome being the most common form, followed by different patterns of unicornuate uterus and MRKH syndrome. An ectopic or absent ovary might be associated with URA in MRKH syndrome and unicornuate uterus.

Evolution of MET and NRAS gene amplification as acquired resistance mechanisms in EGFR mutant NSCLC

EGFR mutant non-small cell lung cancer patients' disease demonstrates remarkable responses to EGFR-targeted therapy, but inevitably they succumb to acquired resistance, which can be complex and difficult to treat. Analyzing acquired resistance through broad molecular testing is crucial to understanding the resistance mechanisms and developing new treatment options. We performed diverse clinical testing on a patient with successive stages of acquired resistance, first to an EGFR inhibitor with MET gene amplification and then subsequently to a combination EGFR and MET targeted therapies. A patient-derived cell line obtained at the time of disease progression was used to identify NRAS gene amplification as an additional driver of drug resistance to combination EGFR/MET therapies. Analysis of downstream signaling revealed extracellular signal-related kinase activation that could only be eliminated by trametinib treatment, while Akt activation could be modulated by various combinations of MET, EGFR, and PI3K inhibitors. The combination of an EGFR inhibitor with a MEK inhibitor was identified as a possible treatment option to overcome drug resistance related to NRAS gene amplification.

Compensatory effects of M. tuberculosis rpoB mutations outside the rifampicin resistance-determining region

Mycobacterium tuberculosis has been observed to develop resistance to the frontline anti-tuberculosis drug rifampicin, primarily through mutations in the rifampicin resistance-determining region (RRDR) of rpoB. While these mutations have been determined to confer a fitness cost, compensatory mutations in rpoA and rpoC that may enhance the fitness of resistant strains have been demonstrated. Recent genomic studies identified several rpoB non-RRDR mutations that co-occurred with RRDR mutations in clinical isolates without rpoA/rpoC mutations and may confer fitness compensation. In this study, we identified 33 evolutionarily convergent rpoB non-RRDR mutations through phylogenomic analysis of public genomic data for clinical M. tuberculosis isolates. We found that none of these mutations, except V170F and I491F, can cause rifampin resistance in Mycolicibacterium smegmatis. The compensatory effects of five representative mutations across rpoB were evaluated by an in vitro competition assay, through which we observed that each of these mutations can significantly improve the relative fitness of the initial S450L mutant (0.97–1.08 vs 0.87). Furthermore, we observed that the decreased RNAP transcription efficiency introduced by S450L was significantly alleviated by each of the five mutations. Structural analysis indicated that the fitness compensation observed for the non-RRDR mutations might be achieved by modification of the RpoB active centre or by changes in interactions between RNAP subunits. Our results provide experimental evidence supporting that compensatory effects are exerted by several rpoB non-RRDR mutations, which could be utilized as additional molecular markers for predicting the fitness of clinical rifampin-resistant M. tuberculosis strains.

Improvement of the immunogenicity of ESAT-6 via fusion with the dodecameric protein dodecin of Mycobacterium tuberculosis

Tuberculosis (TB) is a chronic infectious disease that creates a heavy medical burden worldwide. The only approved vaccine, Bacillus Calmette-Guérin (BCG), cannot fully protect adolescents and adults from TB. Therefore, there is an urgent need to develop an effective new vaccine. Previous studies have found that dodecin, a flavin-binding protein of Mycobacterium tuberculosis (Mtb), can form stable dodecamers and has the potential to improve the immunogenicity of Mtb antigens. In this study, we constructed the fusion protein dodecin-ESAT-6 and evaluated the immunogenicity of dodecin, ESAT-6, and dodecin-ESAT-6 separately. Our results showed that dodecin-ESAT-6 is a dodecameric protein that can withstand heat at 95 °C and under SDS-PAGE conditions. Dodecin-ESAT-6 increased the expression of the costimulatory molecules CD80, CD86, and major histocompatibility complex class II (MHC-II) on the surface of RAW264.7 macrophages. Mice immunized with dodecin-ESAT-6 exhibited higher percentages of antigen-specific CD4⁺ and CD8⁺ T lymphocytes, higher levels of spleen lymphocyte proliferation and IFN-γ and IL-2 secretion, and a lower level of IL-4 secretion than those immunized with ESAT-6. The IgG, IgG1, and IgG2a titers of the dodecin-ESAT-6 group were significantly higher than those of the ESAT-6 group. Dodecin-ESAT-6 elicited a high IgG2a/IgG1 ratio and tended to produce a predominantly Th1-like response. These results support the conclusion that the dodecin-ESAT-6 dodecameric protein induced strong Th1 immune responses and improved the immunogenicity of ESAT-6, which provides a new strategy for TB vaccine development.

[Preliminary Study on the Secretory Performance of Mycobacterium tuberculosis Hypoxic Response Protein 1 (Rv2626c)]

OBJECTIVE

To verify the secretory ability of the hypoxic response protein 1 (HRP1) encoded by Mycobacterium tuberculosis (Mtb) Rv2626c.

METHODS

The target gene attached with His tag was amplified from the genome of Mtb standard virulence strain H37Rv. The recombinant plasmid contained the above amplified product was constructed and electroporated into Mycobacterium smegmatis (Ms) (MC ²155) to construct a recombinant strain. Protein expression was induced under heat condition, and the expression of protein from the culture filtrates and the bacterial lysates was detected afterward. The 10 kDa culture filtrate antigen (CFP-10) (Ms) and CFP-10 (Mtb) were used as positive controls, and the cytoplasmic protein heat shock protein 65 (GroEL2) (Mtb) was used as negative controls.

RESULTS

The HRP1, GroEL2 (Mtb), CFP-10 (Mtb) and CFP-10 (Ms) were successfully amplified by PCR from recombinant plasmid, and sequencing results of the recombinant plasmid is right, confirming the successful construction of the recombinant plasmid. The recombinant Ms was successfully constructed and it could express the proteins GroEL2 (Mtb), HRP1, CFP-10 (Mtb) and CFP-10 (Ms). The target protein HRP1 was detected in both of the lysate and the culture filtrate of the recombinant strain by Western blot, which was consistent with the positive control CFP-10. The negative control GroEL2 (Mtb) was only detected in the bacterial lysate, but not detected in the culture filtrate.

CONCLUSION

The protein HRP1 encoded by Mtb Rv2626c can be secreted out of Ms by the secretion system of Ms. It may be a secreted protein and play an important role in the pathogenesis of Mtb.

[Optimizing Mycobacterium Recombineering System (pJV53) to Promote the Screening of the Mycobacterium Mutants]

OBJECTIVE

To establish a way for screening Mycobacterium mutants through adding the screening markers into pJV53.

METHODS

The sucrose counter selection gene SacB and mutant hygromycin-resistant gene hyg^S were inserted into pJV53; The recovery of the hygromycin-resistance indicated the successful homologous recombination in Mycobacterium smegmatis (Ms), which could serve as mutant screening marker; The sucrose counter selection could be used to screen the plasmid-free mutants.

RESULTS

The recombinant plasmid pJV53-SacB-hyg^S were successfully constructed. The rifampin-resistant rpoB D516Y and rpoB H526Q mutants and MSMEG_4487 G188A mutant were efficiently screened out. All mutants had shed the plasmid successfully.

CONCLUSION

pJV53-SacB-hyg^S can efficiently contribute to construct and screen the mutants and to get the mutants shedding the plasmid self, which has high value of extensive application; the D516Y and H526Q mutations in gene rpoB of Mycobacterium tuberculosis contribute to its rifampin-resistance.

Cyclic hydrostatic compress force regulates apoptosis of meniscus fibrochondrocytes via integrin α5β1

Meniscus is a semilunar fibrocartilaginous tissue, serving important roles in load buffering, stability, lubrication, proprioception, and nutrition of the knee joint. The degeneration and damage of meniscus has been proved to be a risk factor of knee osteoarthritis. Mechanical stimulus is a critical factor of the development, maintenance and repair of the meniscus fibrochondrocytes. However, the mechanism of the mechano-transduction process remains elusive. Here we reported that cyclic hydrostatic compress force (CHCF) treatment promotes proliferation and inhibits apoptosis of the isolated primary meniscus fibrochondrocytes (PMFs), via upregulating the expression level of integrin α5β1. Consequently, increased phosphorylated-ERK1/2 and phosphorylated-PI3K, and decreased caspase-3 were detected. These effects of CHCF treatment can be abolished by integrin α5β1 inhibitor or specific siRNA transfection. These data indicate that CHCF regulates apoptosis of PMFs via integrin α5β1-FAK-PI3K/ERK pathway, which may be an important candidate approach during meniscus degeneration.

[Mycobacterium Tuberculosis Rv3084 Encodes Functional Esterase and Suppresses the Pro-inflammatory Cytokines in vivo]

OBJECTIVE

To explore the biological characteristics of the esterase LipR encoded by Mycobacterium tuberculosis (MTB) Rv3084 and its immunomodulatory function in vivo.

METHODS

The LipR gene was amplified from MTB H37Rv strain to construct recombinant expression plasmid. After sequencing, the recombinant plasmid was transformed into E. coli for expression and purification of LipR protein. The expressed protein was confirmed with Western blot assay. The hydrolyzing activity of LipR was detected and the factors affecting LipR enzyme activity were analyzed. Mice were intramuscularly injected with 0.1 mL (containing plasmid DNA 100 μg) recombinant eukaryotic plasmid three times (day 1, 8, and 15); seven days after the last injection, the mice were executed, and the lung and spleen were taken for cytokine detection.

RESULTS

The recombinant expression plasmid was successfully constructed and it was found that LipR protein was mainly expressed in the form of inclusion bodies in E. coli with the relative molecular mass of about 33×10 ³. LipR was demonstrated as an alkaline eurythermic esterase, due to the preference of hydrolyzing short carbon chain esters with optimal hydrolyzing activity on pNP-acetate (pNPA, C2) and the capability in tolerance of high pH and temperature; in the presence of different detergents or metal ions, the activity of LipR hydrolyzing pNP-butyrate (pNPB, C4) was inhibited to some extent. In the mouse model, it was found that LipR could inhibit the secretion of interferon-γ (IFN- γ) and interleukin-2 (IL-2), but to stimulate the secretion of IL-10.

CONCLUSION

The esterase LipR may be one of the esterases help M. tuberculosis withstand harsh environment inside the host in collaboration, and simultaneously act as an immune modulator to inhibit the secretion of pro-inflammatory cytokines and consequently impact the killing effect of host immune system against M. tuberculosis.

[Clinical research of minimally invasive spine surgery with Vesselplasty]

Objective: To evaluate the efficacy and safety of Vesselplasty in the treatment of osteoporotic vertebral fractures and vertebral metastases. Methods: From June 2010 to December 2016, data of 81 patients with spinal diseases treated with Vesselplasty in Department of Spinal Surgery, Beijing Friendship hospital, Capital Medical University were retrospectively analyzed. There are 49 cases of vertebral fractures with age (70.2±8.2) years. Among them, 16 cases have posterior vertebral wall breakage, but no symptoms of nerve injury. Clinical result were evaluated with Visual Analogue Scale(VAS) , the kyphotic angle(Cobb's angle) and Oswestry disability index(ODI) was measured preoperatively, postoperatively and follow-up. At the same time, the operation time and cement leakage were recorded. There were 32 patients with vertebral metastases, with age of (69.6±11.1) years old. The posterior wall of the vertebral body was damaged in 22 cases. The VAS scores were recorded and compared preoperatively and postoperatively. The operation time was recorded also. Results: All patients were completed the operation safely and with no complications. Compared with preoperative VAS, postoperative VAS was significantly decreased in all subjects(P<0.05). The average operation time of each vertebral body was 16.2±4.6 min, and the postoperative VAS score significantly decreased (P<0.05), Cobb 's angle from preoperative (13.9±6.0) ° to( 5.2±4.0) ° (P<0.05) in 49 cases of vertebral fracture(58 vertebrae). The clinical results were still satisfied in follow-up . In 32 cases of vertebral metastases(38 vertebrae), the average operation time was (17.6±5.4) min. The postoperative VAS score was obviously decreased also(P<0.05). A small amount of bone cement leakage occurred in 4 cases of 4 vertebrae. The rate of bone cement leakage was 4.2%, but there were no clinical symptoms in these cases. Conclusion: Vesselplasty is a safe and effective treatment of osteoporotic vertebral fractures and vertebral metastases. It can lead to satisfactory clinical effect, partial recovery of vertebral height. Besides, the bone filling mesh can reduce the risk of bone cement leakage, which can provide a new choice for minimally invasive treatment of vertebral fracture and metastases.

[Professor B. Jigmed's conception on the division of stages of history of Mongolian medicine]

The division of stages on the formation and development of Mongolian medicine is a major issue on the history of Mongolian medicine. Based on Mongolian social, economic and cultural development and the characteristics of Mongolian medicine itself, Professor B. Jigmed creatively puts forward the three stages of development of ancient and modern times of Mongolian medicine. He also reasonably sorts out historical materials to comprehensively and systematically display the general picture of its development. This approach exerts great effect on restructuring the body of Mongolian medicine itself, unveils its rule of development, and promotes its disciplinary construction.

[Effect of the Expression of iNOS Induced by Mycobacterium tuberculosis CRISPR-associated Csm4 (Rv2820c) on Intracellular Viability of Mycobacterium smegmatis]

OBJECTIVE

To determine how Csm4 protein expression affects intracellular survival of Mycobacterium smegmatis(MS).

METHODS

Csm 4 gene was amplified by PCR to construct pMV261-Csm4 shuttle expression plasmid. The Csm4 protein expression in MS_Csm4 was detected by Western blot after electroporation of the recombinant plasmid into MS. The growth kinetics of MS_Csm4 in vitro and the influence of reactive N,O species on the growth of MS_Csm4were observed. The intracellular survival of MS_Csm4 and expressions of inducible nitric oxide synthase gene (iNOS) and nitric oxide production (NO) were detected after infection with THP-1 macrophages.

RESULTS

Csm4 protein was successfully expressed in MS_Csm4,which did not affect the growth of the recombinant MS. Reactive N,O species decreased MS_Csm4 colony forming unit (CFU) in vitro. THP-1 increased the expression of iNOS and NO production and decreased intracellular survival of MS_Csm4.

CONCLUSION

Recombinant MS_Csm4 is susceptible to reactive N,O species in vitro. THP-1 promotes NO release and thus discourages intracellular survival of MS.

Double mutation in DNA gyrase confers moxifloxacin resistance and decreased fitness of Mycobacterium smegmatis

Objectives

Ofloxacin and moxifloxacin are the most commonly used fluoroquinolones (FQs) for the treatment of tuberculosis. As a new generation FQ, moxifloxacin has been recommended for the treatment of ofloxacin-resistant TB. However, the mechanism by which ofloxacin-resistant Mycobacterium tuberculosis further gains resistance to moxifloxacin remains unclear.

Methods

We used Mycobacterium smegmatis as a model for studying FQ resistance in M. tuberculosis . Moxifloxacin-resistant M. smegmatis was selected in vitro based on strains with primary ofloxacin resistance. The gyrA and gyrB genes of the resistant strains were sequenced to identify resistance-associated mutations. An in vitro competition assay was applied to explore the influence of gyrA / gyrB mutations on bacterial fitness. Finally, we evaluated the clinical relevance of our findings by analysing the WGS data of 1984 globally collected M. tuberculosis strains.

Results

A total of 57 moxifloxacin-resistant M. smegmatis strains based on five ofloxacin-resistant strains were obtained. Sequencing results revealed that all moxifloxacin-resistant strains harboured second-step mutations in gyrA or gyrB . The relative fitnesses of the double-mutation strains varied from 0.65 to 0.93 and were mostly lower than those of their mono-mutation parents. From the genomic data, we identified 37 clinical M. tuberculosis strains harbouring double mutations in gyrA and/or gyrB and 36 of them carried at least one low-level FQ-resistance mutation.

Conclusions

Double mutation in DNA gyrase leads to moxifloxacin resistance and decreased fitness in M. smegmatis . Under current dosing of moxifloxacin, double mutations mainly happened in M. tuberculosis strains with primary low-level resistance mutations.

Cauliflower-like Neoplasm of Duodenal Papilla in a Liver Transplant Recipient: What Should We Think and Do? A Case Report

BACKGROUND

With the continuous improvement of liver transplantation technology, the survival rate of liver transplantation has been improved, but recurrent or de novo malignancy remains one of the major factors affecting the long-term survival of liver transplant recipients.

CASE REPORT

A 45-year-old Chinese man had a plastic biliary stent placed on account of biliary anastomotic stenosis after 3 years of piggyback liver transplantation. He came to our hospital because of recurrent fever and jaundice for 2 weeks, and his carcinoembryonic antigen-199 had increased. The patient's duodenal papillary was cauliflower-like at endoscopic retrograde cholangiopancreatography to replace the biliary stent. He was initially suspected of having duodenal papillary carcinoma after liver transplantation. However, the pathology from endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-guided biopsy showed inflammation. While awaiting the result of biopsy, his CA-199 decreased significantly after anti-infection and symptomatic treatment. The patient was diagnosed with biliary anastomotic stenosis and duodenal papillitis. He was discharged uneventfully; to date, there is no evidence of malignant tumor.

CONCLUSIONS

We report this case to provide helpful information to clinicians about the management of the duodenal papilla cauliflower-like neoplasm after liver transplantation, which should be considered as inflammatory first. Perhaps our view can avoid the risk of bringing an excessive medical treatment and unnecessary economic burden to patients and their families.

The truncated Rv2820c of Mycobacterium tuberculosis Beijing family augments intracellular survival of M. smegmatis by altering cytokine profile and inhibiting NO generation

Genetic variations among genes of Mycobacterium tuberculosis may be associated with antigenic variation and immune evasion, which complicates the pathogenesis of M. tuberculosis. The hyper-virulent M. tuberculosis Beijing strains harbored several large sequence deletions, among which RD207 attributed to the deletion of CRISPR loci and several Cas genes. RD207 also gave rise to a truncated gene Rv2820c-Bj with 60% deletion in length at the 3'-end and a new 3'-end of five amino acid mutations. It has been reported that Rv2820c-Bj correlated with enhanced intracellular survival of M. smegmatis in macrophages when compared to its full-length counterpart Rv2820c in M. tuberculosis, however, the respective contribution of the truncation and the new 3'-end of Rv2820c-Bj to this enhancement was unclear. Here, by infecting THP-1 macrophages with Ms_Rv2820c-Bj, Ms_Rv2820c and MS_Rv2820c-Tr (expressing the truncated Rv2820c without five amino acid mutations at 3'-end), we found only Ms_Rv2820c-Bj was responsible for the enhancement of survival of M. smegmatis in macrophages. Furthermore, we detected that Ms_Rv2820c-Tr and Ms_Rv2820c-Bj induced similar cytokine profile and NO production after infection of macrophages, which was distinctly different from Ms_Rv2820c. However, Ms_Rv2820c-Bj evoked higher levels of interleukin-10 (IL-10) and lower levels of interleukin- 6 (IL-6), interleukin-1β (IL-1β) and interleukin-12 (IL-12) in infected THP-1 macrophages than Ms_Rv2820c-Tr. Accordingly, we concluded that the new 3'-end of Rv2820c-Bj was important to dampen host defense and enhance the intracellular survival of M. smegmatis.

A Case Report of Traumatic Rupture of Splenic Pregnancy

Primary splenic pregnancy is a rare type of ectopic pregnancy, which could easily rupture in the early stage of pregnancy, causing life-threatening intraabdominal haemorrhage. Rupture of splenic pregnancy due to trauma is even rarer. We reported a case of splenic pregnancy occurring in a female patient of reproductive age. She was injured by the handlebar on the upper left abdomen while riding a bicycle, causing intraabdominal haemorrhage. Ultrasound showed splenic rupture. The patient underwent emergency surgery, and was diagnosed with a rupture of splenic pregnancy by postoperative pathology. It is an extremely rare case where the patient was diagnosed splenic pregnancy due to a traumatic rupture and haemorrhage. We hope this case can be helpful in the evaluation and diagnosis of acute abdomen in women of reproductive age. (Hong Kong j.emerg.med. 2015;22:312-315)

Risk of low-energy fracture in type 2 diabetes patients: a meta-analysis of observational studies

In this meta-analysis, evidence of an association between type 2 diabetes mellitus (T2DM) and low-energy fractures has been evaluated including 12 observational studies. The results suggested that T2DM patients had an enhanced risk of low-energy fractures.

INTRODUCTION

Type 1 diabetes mellitus (T1DM) patients have been shown to be at enhanced risk of fracture injury, but less is known about low-energy fractures among patients with T2DM.

METHODS

We performed a meta-analysis of 12 observational studies identified in Medline and EMBASE that included 938,742 participants, including 30,827 low-energy fracture cases. The incidence rate ratios (IRRs) of low-energy fractures were determined using a random-effects model.

RESULTS

The IRRs of low-energy fracture for men and women were 1.37 (95% confidence interval [CI], 0.94-2.00; p = 0.096) and 1.22 (95% CI, 1.09-1.35; p = 0.000), respectively, and the overall IRR was 1.23 (95% CI, 1.12-1.35; p = 0.000). The IRRs for hip and vertebral fractures were 1.08 (95% CI, 1.02-1.15; p = 0.007) and 1.21 (95% CI, 0.98-1.48; p = 0.073), respectively. The IRRs of low-energy fracture in case-control, prospective, retrospective, and cross-sectional studies were 1.18 (95% CI, 0.81-1.72; p = 0.380), 1.17 (95% CI, 1.05-1.32, p = 0.006), 1.15 (95% CI, 1.02-1.29; p = 0.020), and 1.60 (95% CI, 1.21-2.12; p = 0.001), respectively. The IRRs of low-energy fracture for less than 5 years, 5 to 10 years, and more than 10 years were 1.30 (95%, CI 1.13-1.50; p = 0.000), 1.05 (95% CI, 1.03-1.08; p = 0.000), and 1.19 (95% CI, 1.00-1.41; p = 0.049), respectively.

CONCLUSIONS

Patients with T2DM had a greater risk of low-energy fracture especially of the hip, compared with that in non-diabetic subjects. However, since according to our funnel plot a publication bias may be present and due to study heterogeneity as well as the limited number of publications, the finding needs to be interpreted with caution.

Mycobacterium tuberculosis hypoxic response protein 1 (Hrp1) augments the pro-inflammatory response and enhances the survival of Mycobacterium smegmatis in murine macrophages

PURPOSE

The DosR/DosS two-component regulatory system of Mycobacterium tuberculosis regulates the expression of numerous genes under stress conditions and is important for the long-term survival of M. tuberculosis in the host. The rv2626c gene of M. tuberculosis is one of the most strongly induced transcripts of the dormancy regulon. This study focused on the immunological effects and possible function of Rv2626c in maintaining mycobacterial survival under various stress conditions.

METHODOLOGY

We heterologously expressed the Rv2626c protein in Mycobacterium smegmatis by constructing a recombinant strain Ms_rv2626c. The viability of Ms_rv2626c was evaluated both in vivo and ex vivo. Different stress conditions, including acidified sodium nitrite, malachite green, low pH, SDS and lysozyme, were used to evaluate the effect of Rv2626c on bacterial resistance. An in vitro assay using a macrophage infection model was utilized to investigate the potential effect of Rv2626c to alter the immune response of host cell and its associated pathways. The effect of Rv2626c on cell necrosis was also explored.

RESULTS

The expression of Rv2626c-enhanced M. smegmatis survival under hypoxia and nitric oxide stress in vitro, and this enhancement was maintained within macrophages and in mouse tissues. In addition, macrophages infected with M. smegmatis expressing Rv2626c showed significantly higher interleukin-1β (IL-1β), IL-6, tumour necrosis factor-α (TNF-α) and inducible nitric oxide synthase (iNOS) expression, as well as a higher level of cell necrosis, compared with the control.

CONCLUSION

M. tuberculosis protein Rv2626c plays a significant role in stimulating macrophages to provoke a pro-inflammatory response and in mycobacterial survival during infection.

Genomewide differential expression profiling of long non-coding RNAs in androgenetic alopecia in a Chinese male population

BACKGROUND

Androgenetic alopecia (AGA), or male pattern baldness (MPB), is the most common form of hair loss in males. A combination of genetic and androgen causes have been suggested as factors that contribute to the development of AGA. However, the specific molecular mechanisms that underly AGA remain largely unknown. Long non-coding RNAs (lncRNAs), a new class of regulatory non-coding RNAs that are longer than 200 nucleotides, have been shown to play important roles in a number of cellular processes, including transcription, chromosome remodelling and post-transcriptional processing. The dysregulation of lncRNAs is associated with many forms of diseases, but it remains unknown whether lncRNAs are associated with AGA.

OBJECTIVE

The aim of this study was to identify AGA-associated lncRNAs and predict the potential roles of these lncRNAs in AGA.

METHODS

A genomewide microarray was used to identify lncRNAs that are differentially expressed between AGA and adjacent normal tissues. Real-time qRT-PCR was used to validate the microarray data.

RESULTS

A large number of lncRNAs were differentially expressed (fold change >2.4) between AGA and adjacent normal tissues. Of these, 770 were upregulated and 1373 were downregulated. Moreover, pathway analysis revealed that 53 functional pathways were associated with the upregulated transcripts, while 11 pathways were associated with the downregulated transcripts.

CONCLUSION

To our knowledge, this is the first study to investigate AGA-associated lncRNAs. lncRNA profiles are altered in AGA, and these lncRNAs and their target genes may serve as novel candidates for preventing and treating AGA.

Low-residue diet fed to rabbits induces histomorphological and biomechanical remodeling of small intestine

BACKGROUND

The composition of ingested food is important for the gut microbiome and intestinal homeostasis. We have previously demonstrated that the structure and mechanical properties in the small intestine remodel significantly during fasting. However, it is not clear to what extent the intestinal mechanical properties changes when the composition of food is changed. This study aimed to investigate the passive biomechanical properties and intestinal tissue remodeling in rabbits fed a low-residue diet.

METHODS

New Zealand rabbits (control group n=6, intervention group n=7) were studied. Segments from duodenum, jejunum and ileum were excised. The intestinal diameter and length were obtained from digitized images of the segments at preselected luminal pressure levels and at no-load and zero-stress states. Circumferential and longitudinal stresses (force per area) and strains (deformation) were computed from the length, diameter and pressure data referenced to the zero-stress state geometry. Histomorphometric data were also obtained.

KEY RESULTS

The wet weight-per-unit length, wall thickness and wall area decreased in the intervention group (P<.05, P<.01). Histological measurement confirmed that the wall thickness decreased in all three segments, which was primarily due to mucosal thinning (P<.05). The opening angle tended to increase in all segments in the intervention group. Significant difference between the two groups was found for the jejunum (P<.05). Feeding the low-residue diet shifted the circumferential stress-strain curves in the intervention group to the right, indicating intestinal wall softening.

CONCLUSIONS & INFERENCES

Low-residue diet in rabbits for 1 month induces location-dependent histomorphometric and biomechanical remodeling of the intestine.

Inhibition of miR-660-5p expression suppresses tumor development and metastasis in human breast cancer

Breast cancer, which derives from the epithelium of the mammary glands, is one of the most common cancers diagnosed in women globally. To date, the authors of many studies have reported that the deregulation of microRNAs (miRNAs) plays a crucial role in the occurrence, development, and metastasis of tumors. Here, we discovered that miR-660-5p was upregulated in the breast cancer cell lines MCF7 and MDA-MB-231 compared with that in the normal control cell line CCD-1095Sk. We then inhibited the expression of miR-660-5p to investigate its biological function in cancer development, progression, and metastasis. We determined the changes in the levels of expression of transcription factor CP2 (TFCP2) and CDKN1A to further clarify the specific mechanism involved. The results showed that downregulation of miR-660-5p significantly suppressed the proliferation, migration, and invasion of MCF7 breast cancer cell. Moreover, inhibition of miR-660-5p promoted cell cycle G1 arrest and reduced apoptosis in breast cancer cells. The specific mechanism studies confirmed that TFCP2 was a direct downstream target of miR-660-5p. Aberrant expression of miR-660-5p repressed TFCP2 expression, whereas inhibition of miR-660-5p decreased TFCP2 protein expression, which is a vital factor in the downstream signaling pathway. In conclusion, miR-660-5p can regulate the proliferation, migration, and invasion of human breast cancer cells, and is a novel potential therapeutic target for the clinical treatment of breast cancer.

Immunogenicity and protective efficacy of recombinant Bacille Calmette-Guerin strains expressing mycobacterium antigens Ag85A, CFP10, ESAT-6, GM-CSF and IL-12p70

OBJECTIVE

This study aimed to evaluate the immunogenicity and protective efficacy of recombinant bacille calmette-guerin (rBCG) strains expressing Ag85A (A), CFP10 (C), ESAT6 (E), IL-12p70 (I), and fusion protein GM-CSF (G).

METHOD

rBCGs were established by integrating of A, C, E, I, G, AE, CE, IE, GC, GE and GCE into Mycobacterium bovis BCG-1173 and BCG-SH. The macro-effects of rBCGs on mice were evaluated by phenotype and weight. The immunogenicity of rBCGs was analyzed by lgG, lgG1 and lgG2a antibody titers, and IFN-γ and IL-4 contents through Enzyme-linked immunosorbent assay (ELISA). Meanwhile, the proportions of CD4⁺ and CD8⁺ T splenic lymphocytes were determined using flow cytometry. The protective efficacy of rBCGs was evaluated by bacterial load in spleen and lung tissues from immunized mice.

RESULTS

rBCGs exhibited no obvious side effects on mice. The antibody titers of lgG, lgG1 and lgG2a, proportion of CD4⁺ and CD8⁺ T cells, and concentrations of IFN-γ were found to be significantly higher in multiple-gene rBCGs than that in single-gene rBCGs (P < 0.05). Bacterial load in both spleen and lung tissues from mice infected with M. tuberculosis H37Rv were significantly reduced by rBCGs. A significantly lower bacterial load was revealed in rBCG-1173:A compared with multiple-gene rBCGs (P < 0.05).

CONCLUSION

Immunogenicity was better on multiple-gene rBCGs than on single-gene rBCGs, while excellent protective efficacy was exhibited on rBCG-1173:A and BCG-1173.

Mycobacterium tuberculosis EspB protein suppresses interferon-γ-induced autophagy in murine macrophages

BACKGROUND

Mycobacterium tuberculosis (Mtb) persists within immature phagosomes by preventing their maturation into phagolysosomes. Although the early secretory antigenic target 6 (ESAT-6) system 1 (ESX-1) secretion-associated protein B (EspB) of Mtb is strongly linked to immunogenicity and virulence of this organism, its mechanism of action remains largely unclear. This study aimed to investigate EspB effects on autophagy in murine ANA-1 macrophage cells.

METHODS

EspB gene was amplified by polymerase chain reaction from Mtb H37Rv genomic DNA to express recombinant EspB protein. Levels of autophagic markers, including Microtubule-associated protein 1 light chain 3 beta (LC3B-I and -II), phosphorylated signal transducer and activator of transcription (STAT)1 and total STAT1 in ANA-1 cells treated with EspB proteins were assessed by Western blotting. In addition, autophagic vacuoles were detected by fluorescence microscopy. Finally, IFN-γR1 expression was evaluated by semiquantitative reverse transcriptase polymerase chain reaction and flow cytometry.

RESULTS

EspB gene was expressed in Escherichia coli cells to yield a soluble N-terminal glutatione S-transferase tag fusion protein used in subsequent experiments. Preincubation with EspB significantly suppressed autophagosome formation and LC3B expression induced by interferon (IFN)-γ stimulation, in a dose-dependent manner. These results were confirmed by the reduced incorporation of monodansylcadaverine, a marker for the acidic compartment of autolysosomes, after treatment with EspB. Interestingly, we found that IFN-γ receptor 1 mRNA and protein levels were decreased in EspB-stimulated ANA-1 cells in comparison with untreated cells. Finally, EspB protein also inhibited IFN-γ-activated STAT1 phosphorylation, thereby downmodulating macrophage responsiveness to IFN-γ.

CONCLUSION

EspB inhibits autophagosome formation in murine macrophages, at least in part by downregulating IFN-γ receptor 1 expression. Overall, EspB should be considered a relevant factor in the pathogenesis of mycobacterial infections in humans.

[Clinical characteristics of bone disease in multiple myeloma and clinical significance of monitoring bone metabolic markers]

OBJECTIVE

To observe the clinical characteristics of bone disease in patients with multiple myeloma (MM) and the clinical significance of monitoring bone metabolic markers.

METHODS

The data of 178 MM cases newly diagnosed in Beijing Ji Shui Tan Hospital from January 2009 to June 2014 were reviewed to analysis the types and classification of bone disease and to observe the clinical characteristics of patients with different grades of bone disease. The levels of bone metabolic markers total procollagen type Ⅰ N-terminal peptide (tPINP) and β C-terminal telopeptide of type Ⅰ collagen (β-CTX) were monitored regularly in the two years following treatment in 66 cases.

RESULTS

(1) Among the 178 newly diagnosed MM cases, 167 cases complained of pain in bones on first visit, 35 cases combined with hypercalcemia, 83 cases combined with osteoporosis, 154 cases combined with osteolytic bone destruction, and 73 cases combined with pathologic fracture. The most common osteolytic location was the spine. The most common fracture sites was the spine. (2) According to bone disease grading, the 178 cases were divided into group A (bone grade 0-2, n=51) and group B(bone grade 3-4, n=127). There were no significant differences between group A and group B in gender, median age, therapeutic effect/ineffec, median overall survival, median progress-free survival, mean serum lactic dehydrogenase, mean albumin, urine light chains and serum creatinine(all P>0.05). Compared with group A, group B had lower hemoglobin level[(99.78±29.93)vs (108.84±29.30) g/L], and higher blood calcium level[(2.47±0.40)vs (2.30±0.29) mmol/L], serum β2-microglobuin level[(6.04±4.84)vs (4.12±3.97)mg/L], and bone marrow plasma cells percentage(33.30%±24.87% vs 23.51%±22.67%)(all P<0.05). (3) Before treatment, the levels of β-CTX and tPINP in patients of group B(n=47) were higher than those in group A(n=19)(median 0.78 vs 0.42 μg/L, 60.95 vs 43.47 μg/L, both P<0.05). The ratio of β-CTX /tPINP in group B was higher than that in group A (median 0.017 vs 0.012, P<0.05). After chemotherapy for 3 months, there were no differences in the level of tPINP compared with that before treatment in both group A and group B (both P>0.05), the level of β-CTX decreased significantly compared with that before treatment in both groups(median 0.16 vs 0.42 μg/L, 0.26 vs 0.78 μg/L, both P<0.05); the ratio of β-CTX /tPINP decreased significantly compared with that before treatment in both group A and in group B(median 0.008 vs 0.012, 0.011 vs 0.017, both P<0.05). There were no differences in the level of β-CTX, tPINP and β-CTX/tPINP ratio after treatment for 6 months, 1 year and 2 years compared with that after 3 months in both group A and group B (all P>0.05). (4)All patients were divided into two groups according to the therapeutic effect: effective group included patients who reach the effect of partial remission or better remission(n=48), while ineffective group included patients who did not reach the effect of partial remission(n=18). Before treatment there were no differences in the level of β-CTX, tPINP and β-CTX/tPINP ratio between the effective groupand the ineffective group (all P>0.05). After chemotherapy for 3 months, there were no differences in the level of tPINP compared with that before treatment in both effective group and ineffective group (all P>0.05), but the level of β-CTX decreased significantly compared with that before treatment both in effective group and ineffective group (median 0.24 vs 0.60 μg/L, 0.44 vs 0.95 μg/L, both P<0.05). The ratio of β-CTX /tPINP decreased significantly compared with that before treatment both in effective group and ineffective group (median 0.005 vs 0.012, 0.005 vs 0.011, both P<0.05). There were no differences in the level of β-CTX, tPINP and β-CTX/tPINP ratio after treatment for 6 months, 1 year and 2 years compared with that for 3 months both in effective group and ineffective group (all P>0.05).

CONCLUSIONS

Pain in bones, osteolysis and pathological fracture are the most common clinical manifestations in myeloma-related bone disease. The severity of bone disease can reflect the tumor load, but may not affect the therapeutic effect and the overall survival. The bone metabolic markers tPINP and β-CTX can be used to evaluate the severity of myeloma-related bone disease at diagnosis and to monitor the effect of treatment for bone disease.

[The prognostic significance of proportion of blasts in bone marrow on day 14 during induction chemotherapy in patients with adult Ph-negative acute lymphoblastic leukemia]

OBJECTIVE

To investigate the prognostic significance of proportion of the blasts in bone marrow on day 14 (D14) during induction chemotherapy in patients with adult Ph-negative acute lymphoblastic leukemia (Ph (-) ALL).

METHODS

Newly diagnosed Ph (-) ALL patients with bone marrow morphology analysis on day 14 during induction chemotherapy were analyzed retrospectively. The proportion of the D14 blasts which had an impact on achieving a CR by the first induction chemotherapy and outcomes were determined by ROC curve.

RESULTS

166 ALL patients including 94 male and 72 female were analyzed. The median age was 32 years (range, 18-64 years). The CR rate by the first induction chemotherapy was 74.7% with a total CR rate as 93.3%. By ROC analysis, 7.5% of the D14 blasts had the best sensitivity and specificity. The patients with D14 blasts ≥7.5% had lower CR rates after the first and overall induction chemotherapy compared with those with D14 blasts <7.5% (42.7% vs 85.9%, P<0.001 and 75.9% vs 95.6%, P=0.001 respectively). The probabilities of 5-year disease free survival (DFS) and 5-year overall survival (OS) were higher in the patients with D14 blasts<7.5% than those with D14 blasts ≥7.5% (49.8% vs 29.6%, P=0.006 and 52.4% vs 32.6%, P=0.010 respectively). Multivariate analysis showed that higher WBC or central nervous system leukemia at diagnosis, D14 blasts ≥7.5%, no CR after the first induction chemotherapy and receiving consolidation and maintenance chemotherapy rather than transplant were associated with poor outcomes.

CONCLUSIONS

Higher proportion of D14 blasts in bone marrow during the first induction therapy indicated poor prognosis in adult Ph(-) ALL.

The Mycobacterium bovis BCG prime-Rv0577 DNA boost vaccination induces a durable Th1 immune response in mice

Tuberculosis remains a major global health problem and effective vaccines are urgently needed. In this study, we used the combined DNA- and protein-based vaccines of immunodominant antigen Rv0577 to boost BCG and evaluated their immunogenicity in BALB/c mice. Our data suggest that the booster vaccine may substantially enhance the immunogenicity of BCG and strengthen both CD4+ T cell-mediated Th1 and CD8+ T cell-mediated cytolytic responses. Compared with the protein-based vaccine, the DNA-based vaccine can induce more durable Th1 immune response, characterized by high levels of antibody response, proliferation response, percentages of CD4+/CD8+ and cytokine secretion in antigen-stimulated splenocyte cultures. In conclusion, we for the first time, developed a protein- and plasmid DNA-based booster vaccine based on Rv0577. Our findings suggest that antigen Rv0577-based DNA vaccine is immunogenic and can efficiently boost BCG, which could be helpful in the design of an efficient vaccination strategy against TB.

[Comparison of efficacy and prognostic factors in elderly acute myelogenous patients with MA or CAG induction chemotherapy regimen]

OBJECTIVE

To analyze the difference of efficacy and prognostic factors between MA and CAG induction chemotherapy in elderly acute myelogenous leukemia (AML) patients.

METHODS

From April 2009 to September 2015, 103 consecutive hospitalized 60-plus-year-old AML patients were retrospectively analyzed. NPM1 positive FLT3-ITD negative accounted for 17 cases (16.7%). Sixty-five patients received MA regimen and thirty-eight patients received CAG regimen. MA group had higher WBC and FLT3-ITD positive mutations at diagnosis compared with CAG group (P=0.001, P=0.005; respectively). The median follow-up was 13 months for all patients and 17 months for the survivors.

RESULTS

Six patient (5.8%) died in early phase. Complete remission (CR) rate after the first cycle of induction chemotherapy was 51.5% (50/97). Overall CR rate was 70.1% (68/97). CR rate after the first cycle of induction chemotherapy and overall CR rate were indiscriminate between MA and CAG regimen. The time to neutrophil count recovery, the time to platelet count recovery and the number of platelet transfusions were indiscriminate between MA and CAG regimen. Among 68 CR patients, 23 patients relapsed at median 9 months, and cumulative incidence of relapse (CIR) at 3 years was (52.5±10.1)%. Median overall survival (OS) was 20 months. OS rate at 3 years was 32.2%. Median disease-free survival (DFS) was 28 months. DFS rate at 3 years was 43.7%. CIR, DFS and OS at 3 years were indiscriminate between MA and CAG regimen. Multivariate analysis showed that less than 70 years of age (P=0.001), achieved CR (P<0.001), and NPM1 (+) FLT3-ITD(-) mutation (P=0.044) were the independent factors for increasing OS. NPM1(+) FLT3-ITD(-) mutation was the independent factor for increasing DFS (P=0.042). Patients were classified by three prognosis factors: <70 ages, CR, and NPM1(+)FLT3-ITD(-) mutation. Patients with no poor prognosis factors were classified as low risk (n=13), with one factor as medium risk (n=52) and with two and more factors as high risk (n=31). There were significant differences in OS rate and DFS rate at 3 years for 3 groups patients (60.5% vs 48.1% vs 0, P<0.001; 60.2% vs 39.4% vs 0, P=0.045; respectively). OS and DFS at 3 years for 3 groups' patients were indiscriminate between MA and CAG regimen.

CONCLUSIONS

There was indiscrimination of efficacy among MA and CAG induction chemotherapy in old AML patients. Less than 70 years of age, CR and NPM1(+)FLT3-ITD(-) mutation were the independent factors for better survival.

High-density interspecific genetic linkage mapping provides insights into genomic incompatibility between channel catfish and blue catfish

Catfish is the leading aquaculture species in the United States. The interspecific hybrid catfish produced by mating female channel catfish with male blue catfish outperform both of their parent species in a number of traits. However, mass production of the hybrids has been difficult because of reproductive isolation. Investigations of genome structure and organization of the hybrids provide insights into the genetic basis for maintenance of species divergence in the face of gene flow, thereby helping develop strategies for introgression and efficient production of the hybrids for aquaculture. In this study, we constructed a high-density genetic linkage map using the hybrid catfish system with the catfish 250K SNP array. A total of 26,238 SNPs were mapped to 29 linkage groups, with 12,776 unique marker positions. The linkage map spans approximately 3240 cM with an average intermarker distance of 0.25 cM. A fraction of markers (986 of 12,776) exhibited significant deviation from the expected Mendelian ratio of segregation, and they were clustered in major genomic blocks across 15 LGs, most notably LG9 and LG15. The distorted markers exhibited significant bias for maternal alleles among the backcross progenies, suggesting strong selection against the blue catfish alleles. The clustering of distorted markers within genomic blocks should lend insights into speciation as marked by incompatibilities between the two species. Such findings should also have profound implications for understanding the genomic evolution of closely related species as well as the introgression of hybrid production programs in aquaculture.