Hi-C, a chromatin 3D structure technique advancing the functional genomics of immune cells.

The functional performance of immune cells relies on a complex transcriptional regulatory network. The three-dimensional structure of chromatin can affect chromatin status and gene expression patterns, and plays an important regulatory role in gene transcription. Currently available techniques for studying chromatin spatial structure include chromatin conformation capture techniques and their derivatives, chromatin accessibility sequencing techniques, and others. Additionally, the recently emerged deep learning technology can be utilized as a tool to enhance the analysis of data. In this review, we elucidate the definition and significance of the three-dimensional chromatin structure, summarize the technologies available for studying it, and describe the research progress on the chromatin spatial structure of dendritic cells, macrophages, T cells, B cells, and neutrophils.

Targeted Delivery of Abaloparatide to Spinal Fusion Site Accelerates Fusion Process in Rats.

Spinal fusions are performed to treat congenital skeletal malformations, spondylosis, degenerative disk diseases, and other pathologies of the vertebrae that can be resolved by reducing motion between neighboring vertebrae. Unfortunately, up to 100,000 fusion procedures fail per year in the United States, suggesting that efforts to develop new approaches to improve spinal fusions are justified. We have explored whether the use of an osteotropic oligopeptide to target an attached bone anabolic agent to the fusion site might be exploited to both accelerate the mineralization process and improve the overall success rate of spinal fusions. The data presented below demonstrate that subcutaneous administration of a modified abaloparatide conjugated to 20 mer of D-glutamic acid not only localizes at the spinal fusion site but also outperforms the standard of care (topically applied BMP2) in both speed of mineralization (p < 0.05) and overall fusion success rate (p < 0.05) in a posterior lateral spinal fusion model in male and female rats, with no accompanying ectopic mineralization. Because the bone-localizing conjugate can be administered ad libitum post-surgery, and since the procedure appears to improve on standard of care, we conclude that administration of a bone-homing anabolic agent for improvement of spinal fusion surgeries warrants further exploration.

A mouse Model of Focal Vascular Injury Induces Astrocyte Reactivity, Tau Oligomers, and Aberrant Behavior.

Neuropsychiatric symptom development has become more prevalent with 270,000 blast exposures occurring in the past 10 years in the United States. How blast injury leads to neuropsychiatric symptomology is currently unknown. Preclinical models of blast-induced traumatic brain injury have been used to demonstrate blood-brain barrier disruption, degenerative pathophysiology, and behavioral deficits. Vascular injury is a primary effect of neurotrauma that can trigger secondary injury cascades and neurodegeneration. Here we present data from a novel scaled and clinically relevant mouse blast model that was specifically developed to assess the outcome of vascular injury. We look at the biochemical effects and behavioral changes associated with blast injury in young-adult male BALB/c mice. We report that blast exposure causes focal vascular injury in the Somatosensory Barrel Field cortex, which leads to perivascular astrocyte reactivity, as well as acute aberrant behavior. Biochemical analysis revealed that mild blast exposure also invokes tauopathy, neuroinflammation, and oxidative stress. Overall, we propose our model to be used to evaluate focal blood-brain barrier disruption and to discover novel therapies for human neuropsychiatric symptoms.

The emergence and outbreak of multidrug-resistant typhoid fever in China.

Typhoid fever remains a severe public health problem in developing countries. The emergence of resistant typhoid, particularly multidrug-resistant typhoid infections, highlights the necessity of monitoring the resistance characteristics of this invasive pathogen. In this study, we report a typhoid fever outbreak caused by multidrug-resistant Salmonella enterica serovar Typhi strains with an ACSSxtT pattern. Resistance genes conferring these phenotypes were harbored by a large conjugative plasmid, which increases the threat of Salmonella Typhi and thus requires close surveillance for dissemination of strains containing such genes.

Bryostatin extends tPA time window to 6 h following middle cerebral artery occlusion in aged female rats.

Blood-brain barrier (BBB) disruption and hemorrhagic transformation (HT) following ischemic/reperfusion injury contributes to post-stroke morbidity and mortality. Bryostatin, a potent protein kinase C (PKC) modulator, has shown promise in treating neurological injury. In the present study, we tested the hypothesis that administration of bryostatin would reduce BBB disruption and HT following acute ischemic stroke; thus, prolonging the time window for administering recombinant tissue plasminogen activator (r-tPA). Acute cerebral ischemia was produced by reversible occlusion of the right middle cerebral artery (MCAO) in 18-20-month-old female rats using an autologous blood clot with delayed r-tPA reperfusion. Bryostatin (or vehicle) was administered at 2 h post-MCAO and r-tPA was administered at 6 h post-MCAO. Functional assessment, lesion volume, and hemispheric swelling measurements were performed at 24 h post-MCAO. Assessment of BBB permeability, measurement of hemoglobin, assessment of matrix metalloproteinase (MMP) levels by gel zymography, and measurement of PKCε, PKCα, PKCδ expression by western blot were conducted at 24 h post-MCAO. Rats treated with bryostatin prior to r-tPA administration had decreased mortality and hemispheric swelling when compared with rats treated with r-tPA alone. Administration of bryostatin also limited BBB disruption and HT and down-regulated MMP-9 expression while up-regulating PKCε expression at 24 h post-MCAO. Bryostatin administration ameliorates BBB disruption and reduces the risk of HT by down-regulating MMP-9 activation and up-regulating PKCε. In this proof-of-concept study, bryostatin treatment lengthened the time-to-treatment window and enhanced the efficacy and safety of thrombolytic therapy.

Sero-survey of polio antibodies during wild poliovirus outbreak in southern Xinjiang Uygur Autonomous Region, China.

BACKGROUND: After being polio free for more than 10 years, an outbreak following importation of wild poliovirus (WPV) was confirmed in Xinjiang Uygur Autonomous Region, China, in 2011. METHODS: A cross-sectional study was conducted prior to supplementary immunization activities (SIAs), immediately after the confirmation of the WPV outbreak. In selected prefectures, participants aged ≤ 60 years old who visited hospitals at county-level or above to have their blood drawn for reasons not related to the study, were invited to participate in our study. Antibody titers ≥ 8 were considered positive. RESULTS: Among the 2,611 participants enrolled, 2,253 (86.3%), 2,283 (87.4%), and 1,989 (76.2%) were seropositive to P1, P2 and P3 respectively, and 1744 (66.8%) participants were seropositive to all the three serotypes. Lower antibody seropositivities and geometric mean titers were observed in children <1 year of age and in adults aged 15-39 years. CONCLUSION: Serosurveys to estimate population immunity in districts at high risk of polio importation might be useful to gauge underlying population immunity gaps to polio and possibly to guide preparedness and response planning. Consideration should be given to older children and adults during polio risk assessment planning and outbreak response.

Combination treatment of r-tPA and an optimized human apyrase reduces mortality rate and hemorrhagic transformation 6h after ischemic stroke in aged female rats.

Recombinant tissue plasminogen activator (r-tPA) is the only FDA-approved drug treatment for ischemic stroke and must be used within 4.5h. Thrombolytic treatment with r-tPA has deleterious effects on the neurovascular unit that substantially increases the risk of intracerebral hemorrhage if administered too late. These therapeutic shortcomings necessitate additional investigation into agents that can extend the therapeutic window for safe use of thrombolytics. In this study, combination of r-tPA and APT102, a novel form of human apyrase/ADPase, was investigated in a clinically-relevant aged-female rat embolic ischemic stroke model. We propose that successfully extending the therapeutic window of r-tPA administration would represent a significant advance in the treatment of ischemic stroke due to a significant increase in the number of patients eligible for treatment. Results of our study showed significantly reduced mortality from 47% with r-tPA alone to 16% with co-administration of APT102 and r-tPA. Co-administration decreased cortical (47 ± 5% vs. 29 ± 5%), striatal (50 ± 2%, vs. 40 ± 3%) and total (48 ± 3%vs. 33 ± 4%) hemispheric infarct volume compared to r-tPA alone. APT102 improved neurological outcome (8.9±0.6, vs. 6.8 ± 0.8) and decreased hemoglobin extravasation in cortical tissue (1.9 ± 0.1mg/dl vs. 1.4 ± 0.1mg/dl) striatal tissue (2.1 ± 0.3mg/dl vs. 1.4 ± 0.1mg/dl) and whole brain tissue (2.0 ± 0.2mg/dl vs. 1.4 ± 0.1mg/dl). These data suggest that APT102 can safely extend the therapeutic window for r-tPA mediated reperfusion to 6h following experimental stroke without increased hemorrhagic transformation. APT102 offers to be a viable adjunct therapeutic option to increase the number of clinical patients eligible for thrombolytic treatment after ischemic stroke.

Role of sortase A in the pathogenesis of Staphylococcus aureus-induced mastitis in mice.

Sortase A (SrtA), a transpeptidase, anchors surface proteins with an LPXTG-motif sorting signal to the cell envelope. To determine the role of SrtA in the pathogenesis of Staphylococcus aureus, we constructed a mutant strain, ∆SrtA, by genetic techniques and identified its functions in a S. aureus-induced mastitis mouse model. The histological and myeloperoxidase (MPO) level results showed that the ∆SrtA strain attenuated the inflammatory reaction in the mammary tissue of mice compared with wild-type S. aureus challenge. Additionally, the ELISA results showed that the ∆SrtA strain impaired the induction of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6), and the Western blot results showed that the mutant strain blocked the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) by attenuating the degradation and phosphorylation of signaling pathway molecules such as IκBα, p65 and p38. These results suggest that SrtA is a key virulence factor in the pathogenesis of S. aureus-induced mastitis in mice. It appears that the srtA mutant affected the attachment of S. aureus to host cells, thus attenuating the activation of the NF-κB and MAPK signaling pathways, which regulated the expression of pro-inflammatory cytokines and decreased the susceptibility to mastitis.

Bryostatin improves survival and reduces ischemic brain injury in aged rats after acute ischemic stroke.

BACKGROUND AND PURPOSE: Bryostatin, a potent protein kinase C (PKC) activator, has demonstrated therapeutic efficacy in preclinical models of associative memory, Alzheimer disease, global ischemia, and traumatic brain injury. In this study, we tested the hypothesis that administration of bryostatin provides a therapeutic benefit in reducing brain injury and improving stroke outcome using a clinically relevant model of cerebral ischemia with tissue plasminogen activator reperfusion in aged rats. METHODS: Acute cerebral ischemia was produced by reversible occlusion of the right middle cerebral artery (MCAO) in 18- to 20-month-old female Sprague-Dawley rats using an autologous blood clot with tissue plasminogen activator-mediated reperfusion. Bryostatin was administered at 6 hours post-MCAO, then at 3, 6, 9, 12, 15, and 18 days after MCAO. Functional assessment was conducted at 2, 7, 14, and 21 days after MCAO. Lesion volume and hemispheric swelling/atrophy were performed at 2, 7, and 21 days post-MCAO. Histological assessment of PKC isozymes was performed at 24 hours post-MCAO. RESULTS: Bryostatin-treated rats showed improved survival post-MCAO, especially during the first 4 days. Repeated administration of bryostatin post-MCAO resulted in reduced infarct volume, hemispheric swelling/atrophy, and improved neurological function at 21 days post-MCAO. Changes in αPKC expression and εPKC expression in neurons were noted in bryostatin-treated rats at 24 hours post-MCAO. CONCLUSIONS: Repeated bryostatin administration post-MCAO protected the brain from severe neurological injury post-MCAO. Bryostatin treatment improved survival rate, reduced lesion volume, salvaged tissue in infarcted hemisphere by reducing necrosis and peri-infarct astrogliosis, and improved functional outcome after MCAO.

Identification and control of a poliomyelitis outbreak in Xinjiang, China.

BACKGROUND: The last case of infection with wild-type poliovirus indigenous to China was reported in 1994, and China was certified as a poliomyelitis-free region in 2000. In 2011, an outbreak of infection with imported wild-type poliovirus occurred in the province of Xinjiang. METHODS: We conducted an investigation to guide the response to the outbreak, performed sequence analysis of the poliovirus type 1 capsid protein VP1 to determine the source, and carried out serologic and coverage surveys to assess the risk of viral propagation. Surveillance for acute flaccid paralysis was intensified to enhance case ascertainment. RESULTS: Between July 3 and October 9, 2011, investigators identified 21 cases of infection with wild-type poliovirus and 23 clinically compatible cases in southern Xinjiang. Wild-type poliovirus type 1 was isolated from 14 of 673 contacts of patients with acute flaccid paralysis (2.1%) and from 13 of 491 healthy persons who were not in contact with affected persons (2.6%). Sequence analysis implicated an imported wild-type poliovirus that originated in Pakistan as the cause of the outbreak. A public health emergency was declared in Xinjiang after the outbreak was confirmed. Surveillance for acute flaccid paralysis was enhanced, with daily reporting from all public and private hospitals. Five rounds of vaccination with live, attenuated oral poliovirus vaccine (OPV) were conducted among children and adults, and 43 million doses of OPV were administered. Trivalent OPV was used in three rounds, and monovalent OPV type 1 was used in two rounds. The outbreak was stopped 1.5 months after laboratory confirmation of the index case. CONCLUSIONS: The 2011 outbreak in China showed that poliomyelitis-free countries remain at risk for outbreaks while the poliovirus circulates anywhere in the world. Global eradication of poliomyelitis will benefit all countries, even those that are currently free of poliomyelitis.

Comparison of immunogenicity between inactivated and live attenuated hepatitis A vaccines: a single-blind, randomized, parallel-group clinical trial among children in Xinjiang Uighur Autonomous Region, China.

OBJECTIVES: To compare immunogenicity among an inactivated hepatitis A vaccine (Healive(®)) with one-dose and two-dose regimens, and three kinds of live attenuated vaccines in children. METHODS: A single-blind, randomized, parallel-group clinical trial was conducted among healthy children aged 1.5-6 y in Xinjiang Uighur Autonomous Region, China. Subjects were randomly assigned to 5 groups. Two groups were administered one-dose or two-dose inactivated vaccine and the remaining groups were immunized with one of three kinds of attenuated vaccines, respectively. Serum samples were collected at 6- and 12-mo follow-ups. Anti-HAV IgG was measured with a microparticle enzyme immunoassay. RESULTS: No significant differences were observed in seroconversion rates (seroprotection rates) among the five groups at 6 or 12 mo (p>0.05). The geometric mean concentration (GMC) of anti-HAV IgG was significantly higher in the two-dose Healive(®) group than in the one-dose Healive(®) group and the attenuated vaccine groups at 12 mo (932.4 vs. 112.7, 135.8, 203.3, 212.8 mIU/ml, respectively, p<0.05). In the one-dose Healive(®) group, the GMC was significantly lower than that in the attenuated vaccine B and C groups at 6 mo (152.6 vs. 212, 204 mIU/ml, p<0.05) and at 12 mo (112.7 vs. 203.3, 212.8, p<0.05), but was similar to the attenuated vaccine A group at 12 mo (112.7 vs. 135.8 mIU/ml, p>0.05). The GMCs were significantly higher in the 1-2 y of age group than in the 3-6 y of age group for all types of vaccines except the attenuated vaccine C (p<0.05) at 12 mo. CONCLUSIONS: A higher GMC of anti-HAV IgG was induced in the two-dose Healive(®) than in the one-dose and the attenuated vaccines at 12 mo. The attenuated vaccine B or C produced higher GMCs than the one-dose Healive(®) at 6-12 mo after vaccination.

West nile virus infection in Xinjiang, China.

An outbreak of fever and meningitis/encephalitis occurred in Xinjiang, China, from August 5 to September 3, 2004. In preliminary diagnostic testing, several cerebrospinal fluid (CSF) and serum samples showed positive immunoglobulin M (IgM) antibody to Japanese encephalitis virus. Here, the CSF and serum samples of 6 cases collected at that time were tested by immunofluorescence assay (IFA), enzyme-linked immunosorbent assay (ELISA), and plaque reduction neutralization assay (PRNT) for the existence of IgM antibody or neutralization antibody against West Nile virus (WNV) or other arboviruses. The results demonstrate the evidence of West Nile infection in Xinjiang, China.

Worsened outcome from middle cerebral artery occlusion in aged rats receiving 17ß-estradiol.

Although estrogens are neuroprotective in young adult animal models of stroke, clinical trials demonstrate that estrogens increase the incidence and severity of stroke in aged women. We have previously shown that experimental stroke pathophysiology differs between young adult and aged rats. The aim of this study was to determine the effects of 17ß-estradiol after middle cerebral artery occlusion and reperfusion in young adult and aged female rats. Focal embolic stroke was performed by middle cerebral artery occlusion with fibrin clot followed by reperfusion with i.v. human recombinant tissue plasminogen activator. Histological and functional outcomes were measured at 24 h after middle cerebral artery occlusion with fibrin clot. Aged rats treated with 17ß-estradiol had significantly increased infarct volumes compared with placebo-treated aged rats. Young adult rats treated with 17ß-estradiol had significantly decreased infarct volumes and improved functional outcome compared with ovariectomized young adult rats. Our results suggest that 17ß-estradiol may act in an age-dependent manner in the postischemic rat brain. In young adult rats, it is neuroprotective; chronic treatment with 17ß-estradiol during aging leads to worsened ischemic brain injury in aged female rats.

NOX2 inhibition with apocynin worsens stroke outcome in aged rats.

This study utilized middle cerebral artery occlusion (MCAO) with tissue plasminogen activator (tPA) to assess inhibition of the NOX2 isoform of NADPH oxidase on brain injury and functional recovery in aged rats. Effects of NOX2 on the degree of brain injury and functional recovery following MCAO and tPA reperfusion was assessed in young adult and aged rats. Rats received apocynin (NOX2 inhibitor; 5 mg/kg) or saline 30 min prior to MCAO. At 24 h following MCAO, blood-brain barrier permeability (BBB), stroke infarct volume, edema formation, and oxidative damage were measured. Apocynin treatment in aged rats increased mortality rate and failed to improve functional outcome, total infarct volume, edema formation, and BBB permeability. Aged rats displayed increased BBB permeability to sucrose in the contralateral hemisphere following MCAO and diminished antioxidant capacity in the brain as compared to young adult rats. We conclude that inhibition of NOX2 in the aged rat exacerbates stroke injury and diminishes functional outcome. These results suggest age is an important factor in stroke damage and more rigorous examination of apocynin as a therapeutic agent for treatment of stroke must be done.

Plasminogen activator inhibitor type 1 derived peptide, EEIIMD, diminishes cortical infarct but fails to improve neurological function in aged rats following middle cerebral artery occlusion.

Age is a primary risk factor in stroke that is often overlooked in animal studies. We contend that using aged animals yields insight into aspects of stroke injury and recovery that are masked, or not elicited, in younger animals. In this study, we examined effects of co-administration of a plasminogen activator inhibitor type 1 derived peptide, Glu-Glu-Iso-Iso-Met-Asp (EEIIMD), with tissue plasminogen activator (tPA) on infarct volume and functional outcome in aged rats following a transient middle cerebral artery occlusion. Results of our study showed aged (18-20 months) rats treated with EEIIMD along with tPA had reduced cortical infarction volume. However, aged rats showed no improvement in total infarction volume, edema formation, or functional outcome as compared to aged rats administered only tPA. Young adult rats (3-4 months) treated with EEIIMD showed significant improvement in cortical and total infarction volumes, edema formation, and functional outcome. Striatal infarction volume was unaffected by EEIIMD treatment in both young adult and aged rats. These findings emphasize that physiological differences exist between young adult and aged rats and suggest that taking aging processes into account when assessing stroke may improve our ability to discern which therapeutics can be translated from bench to bedside.

[Genotyping of hepatitis A virus prevalent strains in Xinjiang Hetian of China in 2006].

OBJECTIVE: To analysis the genotypes of wild type hepatitis A virus circulated in Xinjiang Hetian of China in 2006. METHODS: The Vp1-2A region of HAV genome was amplified and sequenced from serum samples collected in Xinjiang Hetian of China in 2006, and subjected to phylogenetic analysis by Neighbor Joining (NJ) method. RESULTS: The nucleotide sequence differences in the VP1-2A region among Xinjiang Hetian HAV strains ranged from 0%-3.9%, all belonged to sub-genotype 1A. Genetically similar strains were identified among Xinjiang Hetian 2006 and Xinjiang Yili 2005 of China isolates. Only 0-2 amino acid differences were found among the Xinjiang Hetian HAV isolates in the VP1-2A region. CONCLUSION: There were different HAV strains existing in the investigated areas, these strains may have different transmission pathways for the spread of the disease. The results indicate the usefulness of molecular epidemiological methods in studying changes in the circulating HAV strains and in tracing transmission routes, and also for effectively control measures to prevent the spread of the disease.

Early disruptions of the blood-brain barrier may contribute to exacerbated neuronal damage and prolonged functional recovery following stroke in aged rats.

We examined the effects of age on stroke progression and outcome in order to explore the association between blood-brain barrier (BBB) disruption, neuronal damage, and functional recovery. Using middle cerebral artery occlusion (MCAO), young (3 months) and aged (18 months) rats were assessed for BBB disruption at 20min post-MCAO, and 24h post-MCAO with tissue plasminogen activator induced reperfusion at 120min. Results showed that BBB disruptions in aged rats occurred early and increased nearly two-fold at both the 20min and 24h time points when compared to young animals. Neuronal damage in aged rats was increased two-fold as compared to young rats at 24h, while no neuronal damage was observed at 20min. Young and aged rats exhibited neurological deficits when compared to sham-controls out to 14 days following MCAO and reperfusion; however, aged rats exhibited more severe onset of deficits and prolonged recovery. Results indicate that aged rats suffer larger infarctions, reduced functional recovery and increased BBB disruption preceding observable neuronal injury.

[Protection of tooth protecting spray against dental carries].

OBJECTIVE: To investigate the growth, adherence and soul production of streptococcus mutans incubated with olitin tooth protecting spray and the effect of specific sample against dental caries. METHODS: Streptococcus mutans were cultured with the sample of Olitin tooth protecting spray. After culturing, S. mutans were observed by Gram stain and by spectrophotometer, and the percentages of the adherent S. mutans were calculated. 40 Wistar rats were divided into 4 groups: group A was control group; group B,C,D was low, middle, high test group respectively. All test groups received samples. The sum of the caries scores was assessed by the Keyes' procedure. RESULTS: The sample did not inhibit the growth of S. mutans, but the long chain was occurred. The adherence of S. mutans cells on the glass was decrease, the pH value was increase to above 6.0. There was a significant lower mean of caries score of test group than control group. CONCLUSION: The sample can prevent the development of dental caries in this experiment. The mechanism may relate with the decrease of adherence of S. mutans.