Multiple Lymphomatous Polyposis of the Intestine with Ileocecal Intussusception Due to Mantle Cell Lymphoma: A Case Report of a 34-Year-Old Man

BACKGROUND Multiple lymphomatous polyposis of the gastrointestinal tract can be associated with the B-cell lymphoma variant, mantle cell lymphoma, with most cases having been described in patients who are more than 50 years-of-age. A rare case of multiple lymphomatous polyposis due to mantle cell lymphoma is reported in a 34-year-old man. CASE REPORT A 34-year-old man presented with paroxysmal abdominal pain followed by spontaneous remission, which had been previously diagnosed as gastritis. An episode of ileocecal intussusception occurred, which was confirmed on imaging studies. The diagnosis of multiple lymphomatous polyposis due to mantle cell lymphoma was confirmed following ileocecal resection and histopathology. The patient refused to receive chemotherapy following surgery. Currently, at two-year follow-up, no further abnormality has been found. A review of the literature has shown the importance of endoscopic evaluation in the diagnosis of lymphomatous polyposis. CONCLUSIONS Multiple lymphomatous polyposis due to mantle cell lymphoma has rarely been described in young patients under the age of 50 years. Gastrointestinal endoscopic examination is important for the early diagnosis of multiple lymphomatous polyposis.

[Investigation of acquired drug-resistant genes and strains relationship in Pseudomonas aeruginosa isolated from burn patients]

Objective: To investigate the acquired drug-resistant genes and strains relationship in 40 strains of Pseudomonas aeruginosa isolated from burn patients. Methods: Forty strains of Pseudomonas aeruginosa isolated from burn patients hospitalized in our burn department from January 2014 to December 2015 were selected, with 20 strains from each year. Kirby-Bauer paper disk diffusion method was used to detect sensitivity of the isolated Pseudomonas aeruginosa to 9 kinds of antibiotics of cefotaxime, ceftazidime, cefepime, imipenem, meropenem, gentamicin, amikacin, ciprofloxacin, and levofloxacin. Polymerase chain reaction was applied to detect 9 kinds of acquired β-lactamase antibiotics-resistant genes, outer membrane porin protein oprD2 genes, 12 kinds of acquired aminoglycosides antibiotics-resistant genes, and 6 kinds of acquired disinfectant-resistant genes and genetic marker genes of mobile genetic elements. Among the above genes, positive expression genes were verified by DNA sequencing and comparison. Sequences of twenty-eight acquired drug-resistant genes of the above 40 Pseudomonas aeruginosa strains were analyzed by unweighted pair-group method with arithmetic means cluster analysis. Results: Forty strains of Pseudomonas aeruginosa were resistant to the above 9 kinds of antibiotics. Two kinds of acquired β-lactamase antibiotics-resistant genes of bla(TEM), bla(CARB), 5 kinds of acquired aminoglycosides antibiotics-resistant genes of aac(6')-Ⅰb, aac(6')-Ⅱ, ant(2″)-Ⅰ, ant(3″)-Ⅰ, and rmtB, and 3 kinds of acquired disinfectant-resistant genes and genetic marker genes of mobile genetic elements of qacE△1-sul1, merA, and intⅠ1were detected in 40 strains of Pseudomonas aeruginosa with oprD2 gene deficiency. Forty strains aggregated obviously, with a total of 7 gene modes and 3 clones. Drug-resistant gene sequences of strains of number 2 to 4, 6 to 9, 11, 14, and 17 to 39 were similar and with close relationship. Drug-resistant gene sequences of number 12 and 13 strains were similar and with close relationship. Drug-resistant sequences of number 10 and 16 strains were similar and with close relationship. Conclusions: Genes of bla(TEM), bla(CARB), aac(6')-Ⅰb, aac(6')-Ⅱ, ant(2″)-Ⅰ, rmtB, qacE△1-sul1, merA, and intⅠ1 were prevalent in these strains of Pseudomonas aeruginosa with oprD2 gene deficiency isolated from burn patients, which may play key roles in resistance of Pseudomonas aeruginosa to β-lactamase, aminoglycoside, and quinolone antibiotics, and the drug-resistant phenotypes were in good coincidence with genotypes. Pseudomonas aeruginosa strains isolated from burn patients were with similar acquired drug-resistant genes and close relationship.

The effect of aggression I: The increases of metabolic cost and mobilization of fat reserves in male striped hamsters

Aggression can benefit individuals by enhancing their dominance and thereby their ability to acquire and retain resources that increase survival or fitness. Engaging in aggressive behavior costs energy and how animals manage their energy budget to accommodate aggression remains unclear. We conducted three experiments to examine changes in physiological, behavioral and hormonal markers indicative of energy budget in male striped hamsters subject to resident-intruder aggression tests. Body temperature, metabolic rate and serum corticosterone levels significantly increased in resident hamsters immediately after the introduction of intruders. Energy intake did not change, but the metabolic rate of residents increased by 16.1% after 42-days of repeated encounters with intruders. Residents had significantly decreased body fat content and serum thyroxine (T₄) levels, and a considerably elevated tri-iodothyronine (T₃)/T₄ ratio compared to a control group that had no intruders. Attack latency considerably shortened, and the number of attack bouts and total duration of attacks, significantly increased in residents on day 42 compared to day 1 of experiments. These findings may suggest that the conversion of T₄ to T₃ is involved in defensive aggression behavior. The mobilization of fat reserves resulting in lean body mass is probably common response to the increased metabolic cost of aggression in small mammals. Aggressive behavior, which is important for the successful acquisition and defense of resources, may be of significance for adaptation and evolution of metabolic rate.

Pathophysiological and behavioral deficits in developing mice following rotational acceleration-deceleration traumatic brain injury

Abusive head trauma (AHT) is the leading cause of death from trauma in infants and young children. An AHT animal model was developed on 12-day-old mice subjected to 90° head extension-flexion sagittal shaking repeated 30, 60, 80 and 100 times. The mortality and time until return of consciousness were dependent on the number of repeats and severity of the injury. Following 60 episodes of repeated head shakings, the pups demonstrated apnea and/or bradycardia immediately after injury. Acute oxygen desaturation was observed by pulse oximetry during respiratory and cardiac suppression. The cerebral blood perfusion was assessed by laser speckle contrast analysis (LASCA) using a PeriCam PSI system. There was a severe reduction in cerebral blood perfusion immediately after the trauma that did not significantly improve within 24 h. The injured mice began to experience reversible sensorimotor function at 9 days postinjury (dpi), which had completely recovered at 28 dpi. However, cognitive deficits and anxiety-like behavior remained. Subdural/subarachnoid hemorrhage, damage to the brain-blood barrier and parenchymal edema were found in all pups subjected to 60 insults. Proinflammatory response and reactive gliosis were upregulated at 3 dpi. Degenerated neurons were found in the cerebral cortex and olfactory tubercles at 30 dpi. This mouse model of repetitive brain injury by rotational head acceleration-deceleration partially mimics the major pathophysiological and behavioral events that occur in children with AHT. The resultant hypoxia/ischemia suggests a potential mechanism underlying the secondary rotational acceleration-deceleration-induced brain injury in developing mice.

Anatomical and functional effects of lateral cervical hemicontusion in adult rats

PURPOSE

Cervical injuries are the most common form of spinal cord injury (SCI), and are often complicated by pathological secondary damage. Therefore, cervical SCI is of great clinical importance for understanding pathology and potential therapies. Here we utilize a weight drop cervical hemi-contusion injury model using a NYU/MASCIS impactor that produced graded anatomical and functional deficits.

METHODS

Three groups of rats were established: 1) Sham (laminectomy only) (n = 6), 12.5 mm weight drop (n = 10), and 25 mm weight drop (n = 10) SCI groups. Forelimb functional assessments of grooming ability, cereal manipulation, and forepaw adhesive removal were performed weekly after injury. Using transcranial magnetic motor evoked potentials (tcMMEPs), supraspinal motor stimulations were recorded in both forelimbs and hindlimbs at 5 and 28d post-injury. Lesion volume and myelinated tissue area were assessed through histological analysis.

RESULTS

A 12.5 mm weight drop height produced considerable tissue damage compared to Sham animals, while a 25 mm drop induced even greater damage than the 12.5 mm drop (p < 0.05). Forelimb functional assessments showed that increased injury severity and tissue damage was correlated to the degree of forelimb functional deficits. Interestingly, the hindlimbs showed little to no motor function loss. Upon tcMMEP stimulation, surprisingly little motor signal was recorded in the hindlimbs despite outward evidence of hindlimb motor recovery.

CONCLUSIONS

Our findings highlight a correlation between anatomical damage and functional outcome in a graded cervical hemi-contusion model, and support a loss of descending motor control from supraspinal inputs and intraspinal plasticity that promote spontaneous hindlimb functional recovery in this model.

An In Vivo Duo-color Method for Imaging Vascular Dynamics Following Contusive Spinal Cord Injury

Spinal cord injury (SCI) causes significant vascular disruption at the site of injury. Vascular pathology occurs immediately after SCI and continues throughout the acute injury phase. In fact, endothelial cells appear to be the first to die after a contusive SCI. The early vascular events, including increased permeability of the blood-spinal cord barrier (BSCB), induce vasogenic edema and contribute to detrimental secondary injury events caused by complex injury mechanisms. Targeting the vascular disruption, therefore, could be a key strategy to reduce secondary injury cascades that contribute to histological and functional impairments after SCI. Previous studies were mostly performed on postmortem samples and were unable to capture the dynamic changes of the vascular network. In this study, we have developed an in vivo duo-color two-photon imaging method to monitor acute vascular dynamic changes following contusive SCI. This approach allows detecting blood flow, vessel diameter, and other vascular pathologies at various sites of the same rat pre- and post-injury. Overall, this method provides an excellent venue for investigating vascular dynamics.

[Survey on dental caries status of migrant children aged 6-12 years in Minhang district of Shanghai]

PURPOSE

To investigate the prevalence of dental caries among migrant children aged 6-12 years in Minhang district of Shanghai, so as to provide some basic data for children health care.

METHODS

Ten thousand and eleven school children in 8 primary schools of Minhang district of Shanghai were investigated by cluster random sampling. Visual examination combined with probe inspection was used to diagnose caries, and then rate of caries and DMFT (decayed，missing and filled teeth) were calculated. SPSS 13.0 software package was used for statistical analysis.

RESULTS

The prevalence of caries among children aged 6-12 years was 67.07%, which was significantly higher than that in children from government-owned schools (61.99%)(P<0.01). The prevalence of caries was 75.82% in 6-year-old group and highest compared to other groups.

CONCLUSIONS

It can't be optimistic about the caries prevalence among migrant children aged 6-12 years in Minhang district，Shanghai.More attentions should be payed in prevention and early intervention of dental caries for children above 6 years old.

Isolation and characterization of Burkholderia fungorum Gan-35 with the outstanding ammonia nitrogen-degrading ability from the tailings of rare-earth-element mines in southern Jiangxi, China

The exploitation of rare-earth-element (REE) mines has resulted in severe ammonia nitrogen pollution and induced hazards to environments and human health. Screening microorganisms with the ammonia nitrogen-degrading ability provides a basis for bioremediation of ammonia nitrogen-polluted environments. In this study, a bacterium with the outstanding ammonia nitrogen-degrading capability was isolated from the tailings of REE mines in southern Jiangxi Province, China. This strain was identified as Burkholderia fungorum Gan-35 according to phenotypic and phylogenetic analyses. The optimal conditions for ammonia–nitrogen degradation by strain Gan-35 were determined as follows: pH value, 7.5; inoculum dose, 10%; incubation time, 44 h; temperature, 30 °C; and C/N ratio, 15:1. Strain Gan-35 degraded 68.6% of ammonia nitrogen under the optimized conditions. Nepeta cataria grew obviously better in the ammonia nitrogen-polluted soil with strain Gan-35 than that without inoculation, and the decrease in ammonia–nitrogen contents of the former was also more obvious than the latter. Besides, strain Gan-35 exhibited the tolerance to high salinities. In summary, strain Gan-35 harbors the ability of both ammonia–nitrogen degradation at high concentrations and promoting plant growth. This work has reported a Burkholderia strain with the ammonia nitrogen-degrading capability for the first time and is also the first study on the isolation of a bacterium with the ammonia nitrogen-degrading ability from the tailings of REE mines. The results are useful for developing an effective method for microbial remediation of the ammonia nitrogen-polluted tailings of REE mines.

Stable Carbon Isotope Composition of the Lipids in Natural Ophiocordyceps sinensis from Major Habitats in China and Its Substitutes

Ophiocordyceps sinensis is one rare medicinal fungus produced in the Qinghai-Tibetan Plateau. Its quality and price varies hugely with different habitat, and its numerous substitutes have sprung up in functional food markets. This paper aims to discriminate the geographic origin of wild O. sinensis and its substitutes via element analyzer-isotope ratio mass spectrometry and gas chromatography-isotope ratio mass spectrometry. The δ13C values of major fatty acids in the lipids of O. sinensis are characterized unanimously by the variation relation C18:0 < C18:2 ≈ C16:0 < C18:1, while their fluctuation intervals are notably different between those of neutral and polar lipids. The comparative analysis of the δ13C ratios of major fatty acids in lipids of O. sinensis suggests that the δ13C patterns may be sensitive potential indicators to discriminate its geographical origin. The δ13C values of individual major fatty acids of lipids from the cultivated stromata of Cordyceps militaris (SCM), the fermented mycelia of Hirsurella sinensis (FMH) and Paecilomyces epiali (FMP) range from -31.2‰ to -29.7‰, -16.9‰ to -14.3‰, and -26.5‰ to -23.9‰, respectively. Their δ13C pattern of individual major fatty acids may be used as a potential indicator to discriminate the products of natural O. sinensis and its substitutes.

Anti-tumor and anti-angiogenic effects of Fucoidan on prostate cancer: possible JAK-STAT3 pathway

BACKGROUND

Prostate cancer is the most common cancer in men in the United States. Fucoidan is a bioactive polysaccharide extracted mainly from algae. The aim of this study was to investigate anti-tumor and anti-angiogenic effects of fucoidan in both cell-based assays and mouse xenograft model, as well as to clarify possible role of JAK-STAT3 pathway in the protection.

METHODS

DU-145 human prostate cancer cells were treated with 100-1000 μg/mL of fucoidan. Cell viability, proliferation, migration and tube formation were studied using MTT, EdU, Transwell and Matrigel assays, respectively. Athymic nude mice were subcutaneously injected with DU-145 cells to induce xenograft model, and treated by oral gavage with 20 mg/kg of fucoidan for 28 days. Tumor volume and weight were recorded. Vascular density in tumor tissue was determined by hemoglobin assay and endothelium biomarker analysis. Protein expression and phosphorylation of JAK and STAT3 were determined by Western blot. Activation of gene promoters was investigated by chromatin Immunoprecipitation.

RESULTS

Fucoidan could dose-dependently inhibit cell viability and proliferation of DU-145 cells. Besides, fucoidan also inhibited cell migration in Transwell and tube formation in Matrigel. In animal study, 28-day treatment of fucoidan significantly hindered the tumor growth and inhibited angiogenesis, with decreased hemoglobin content and reduced mRNA expression of CD31 and CD105 in tumor tissue. Furthermore, phosphorylated JAK and STAT3 in tumor tissue were both reduced after fucoidan treatment, and promoter activation of STAT3-regulated genes, such as VEGF, Bcl-xL and Cyclin D1, was also significantly reduced after treatment.

CONCLUSIONS

All these findings provided novel complementary and alternative strategies to treat prostate cancer.

Optogenetics and its application in neural degeneration and regeneration

Neural degeneration and regeneration are important topics in neurological diseases. There are limited options for therapeutic interventions in neurological diseases that provide simultaneous spatial and temporal control of neurons. This drawback increases side effects due to non-specific targeting. Optogenetics is a technology that allows precise spatial and temporal control of cells. Therefore, this technique has high potential as a therapeutic strategy for neurological diseases. Even though the application of optogenetics in understanding brain functional organization and complex behaviour states have been elaborated, reviews of its therapeutic potential especially in neurodegeneration and regeneration are still limited. This short review presents representative work in optogenetics in disease models such as spinal cord injury, multiple sclerosis, epilepsy, Alzheimer's disease and Parkinson's disease. It is aimed to provide a broader perspective on optogenetic therapeutic potential in neurodegeneration and neural regeneration.

A Tissue Displacement-based Contusive Spinal Cord Injury Model in Mice

Producing a consistent and reproducible contusive spinal cord injury (SCI) is critical to minimizing behavioral and histological variabilities between experimental animals. Several contusive SCI models have been developed to produce injuries using different mechanisms. The severity of the SCI is based on the height that a given weight is dropped, the injury force, or the spinal cord displacement. In the current study, we introduce a novel mouse contusive SCI device, the Louisville Injury System Apparatus (LISA) impactor, which can create a displacement-based SCI with high injury velocity and accuracy. This system utilizes laser distance sensors combined with advanced software to produce graded and highly-reproducible injuries. We performed a contusive SCI at the 10^th thoracic vertebral (T10) level in mice to demonstrate the step-by-step procedure. The model can also be applied to the cervical and lumbar spinal levels.

Increased threshold of short-latency motor evoked potentials in transgenic mice expressing Channelrhodopsin-2

Transgenic mice that express channelrhodopsin-2 or its variants provide a powerful tool for optogenetic study of the nervous system. Previous studies have established that introducing such exogenous genes usually does not alter anatomical, electrophysiological, and behavioral properties of neurons in these mice. However, in a line of Thy1-ChR2-YFP transgenic mice (line 9, Jackson lab), we found that short-latency motor evoked potentials (MEPs) induced by transcranial magnetic stimulation had a longer latency and much lower amplitude than that of wild type mice. MEPs evoked by transcranial electrical stimulation also had a much higher threshold in ChR2 mice, although similar amplitudes could be evoked in both wild and ChR2 mice at maximal stimulation. In contrast, long-latency MEPs evoked by electrically stimulating the motor cortex were similar in amplitude and latency between wild type and ChR2 mice. Whole-cell patch clamp recordings from layer V pyramidal neurons of the motor cortex in ChR2 mice revealed no significant differences in intrinsic membrane properties and action potential firing in response to current injection. These data suggest that corticospinal tract is not accountable for the observed abnormality. Motor behavioral assessments including BMS score, rotarod, and grid-walking test showed no significant differences between the two groups. Because short-latency MEPs are known to involve brainstem reticulospinal tract, while long-latency MEPs mainly involve primary motor cortex and dorsal corticospinal tract, we conclude that this line of ChR2 transgenic mice has normal function of motor cortex and dorsal corticospinal tract, but reduced excitability and responsiveness of reticulospinal tracts. This abnormality needs to be taken into account when using these mice for related optogenetic study.

Label-Free Vibrational Spectroscopic Imaging of Neuronal Membrane Potential

Detecting membrane potentials is critical for understanding how neuronal networks process information. We report a vibrational spectroscopic signature of neuronal membrane potentials identified through hyperspectral stimulated Raman scattering (SRS) imaging of patched primary neurons. High-speed SRS imaging allowed direct visualization of puff-induced depolarization of multiple neurons in mouse brain slices, confirmed by simultaneous calcium imaging. The observed signature, partially dependent on sodium ion influx, is interpreted as ion interactions on the CH₃ Fermi resonance peak in proteins. By implementing a dual-SRS balanced detection scheme, we detected single action potentials in electrically stimulated neurons. These results collectively demonstrate the potential of sensing neuronal activities at multiple sites with a label-free vibrational microscope.

Comparative study of 13 candidate genes applying multi-reference normalization to detect the expression of different fineness in skin tissues of wool sheep

Fiber diameter is a useful indicator of wool traits and it is the main determinant of wool quality and value. A comparative study was conducted to analyze the abundance and expression of 13 candidate genes using expression profile microarray analysis and to identify novel molecular markers associated with wool traits to provide a molecular basis for improving wool quality in sheep. Genes associated with fineness of skin tissue were identified using a real-time reverse transcriptase-polymerase chain reaction method with 18SrRNA, β-Actin, and GAPDH used for multi-reference normalization. The results indicated that the expression levels of TXNIP, TFDP1, and FAIM genes in super-fine type wool sheep were higher than those in fine-type wool sheep; the corresponding expression ratios of super-fine to fine wool sheep were 1.45, 1.57, and 2.55, respectively. The expression levels of PIK3CA, ADAM9, and FZD3 genes were lower in super-fine wool sheep compared with fine-type wool sheep; the corresponding expression ratios were 0.61, 0.65, and 0.52, respectively. The other genes tested (RPS6KA, ABCG2, GSTA1, PTPN13, GJB3, PPARD, and LAMB1) were similarly expressed in both types of wool sheep. These results infer that lower expression of PIK3CA, ADAM9, and FZD3 genes was associated with lower fiber diameter, whereas lower expression of TXNIP, TFDP1, and FAIM genes was associated with higher fiber diameter.

[Expression of PAI-2 mRNA in peripheral blood leucocytes and regulation by sGC activator in pulmonary hypertension]

OBJECTIVE

To investigate the mRNA expression level of plasminogen activator inhibitor-2 (PAI-2) in peripheral blood leucocytes and regulation by soluble guanylate cyclase (sGC) activator in pulmonary hypertension.

METHODS

The human pulmonary arterial smooth muscle cells were treated with sGC activator Cinaciguat. The mRNA and protein expression levels of PAI-2 were detected with Real-time PCR and Western blot. The fresh blood samples of 8 patients with pulmonary arterial hypertension (PAH) (collected at the China-Japan Friendship Hospital from November 2014 to March 2015), 16 patients with chronic thromboembolic pulmonary hypertension (CTEPH) (collected at the China-Japan Friendship Hospital from November 2014 to March 2015), 24 age- and gender- matched healthy controls (collected at Beijing Hospital in March 2015) were treated with Cinaciguat for 8 hours. Then RNA of peripheral leukocytes was extracted and performed with reverse transcription and Real-time PCR to detect the mRNA level of PAI-2, which was compared between healthy controls and patients with pulmonary hypertension, before and after the treatment of Cinaciguat. At last, the correlation of PAI-2 mRNA level and the clinic severity of pulmonary hypertension were identified.

RESULTS

The mRNA and protein expression levels of PAI-2 were promoted by Cinaciguat in human pulmonary arterial smooth muscle cells. The baseline mRNA level of PAI-2 in peripheral leukocytes was significantly lower in PAH patients compared to the healthy controls (0.201±0.152, 0.660±0.440, P=0.021). There was no significant difference in the mRNA expression level of PAI-2 between the CTEPH patients and controls (0.428±0.364, 0.769±0.682, P=0.152). After Cinaciguat treatment, the mRNA expression levels of PAI-2 were up-regulated in PAH patients and CTEPH patients (1.352±1.127, 1.203±1.008), there was no significant difference in the mRNA expression level of PAI-2 among the PAH patients, CTEPH patients and controls (P=0.130, P=0.534). The baseline mRNA level of PAI-2 was negative correlated with echocardiography-estimated systolic pulmonary arterial pressure (sPAP) (r=-0.744, P=0.034).

CONCLUSIONS

The mRNA expression level of PAI-2 is significantly down-regulated in peripheral blood leucocytes and up-regulated by sGC activator in pulmonary hypertension. PAI-2 could be used as potential biomarker of pulmonary vascular remodeling in PAH.

Transplantation of Pro-Oligodendroblasts, Preconditioned by LPS-Stimulated Microglia, Promotes Recovery After Acute Contusive Spinal Cord Injury

Spinal cord injury (SCI) is a significant clinical challenge, and to date no effective treatment is available. Oligodendrocyte progenitor cell (OPC) transplantation has been a promising strategy for SCI repair. However, the poor posttransplantation survival and deficiency in differentiation into myelinating oligodendrocytes (OLs) are two major challenges that limit the use of OPCs as donor cells. Here we report the generation of an OL lineage population [i.e., pro-oligodendroblasts (proOLs)] that is relatively more mature than OPCs for transplantation after SCI. We found that proOLs responded to lipopolysaccharide (LPS)-stimulated microglia conditioned medium (L+M) by preserving toll-like receptor 4 (TLR4) expression, improving cell viability, and enhancing the expression of a myelinating OL marker myelin basic protein (MBP), compared to other OL lineage cells exposed to either LPS-stimulated (L+M) or nonstimulated microglia conditioned medium (LM). When L+M-stimulated proOLs were intrathecally delivered through a lumbar puncture after a T10 thoracic contusive SCI, they promoted behavioral recovery, as assessed by the BassoBeattieBresnahan (BBB) locomotor rating scale, stride length, and slips on the grid tests. Histologically, transplantation of L+M proOLs caused a considerable increase in intralesional axon numbers and myelination, and less accumulation of invading macrophages when compared with the vehicle control or OPC transplantation. Thus, transplantation of proOLs, preconditioned by L+M, may offer a better therapeutic potential for SCI than OPCs since the former may have initiated the differentiation process toward OLs prior to transplantation.

RhoA/Rho Kinase Mediates Neuronal Death Through Regulating cPLA2 Activation

Activation of RhoA/Rho kinase leads to growth cone collapse and neurite retraction. Although RhoA/Rho kinase inhibition has been shown to improve axon regeneration, remyelination and functional recovery, its role in neuronal cell death remains unclear. To determine whether RhoA/Rho kinase played a role in neuronal death after injury, we investigated the relationship between RhoA/Rho kinase and cytosolic phospholipase A₂ (cPLA₂), a lipase that mediates inflammation and cell death, using an in vitro neuronal death model and an in vivo contusive spinal cord injury model performed at the 10th thoracic (T10) vertebral level. We found that co-administration of TNF-α and glutamate induced spinal neuron death, and activation of RhoA, Rho kinase and cPLA₂. Inhibition of RhoA, Rho kinase and cPLA₂ significantly reduced TNF-α/glutamate-induced cell death by 33, 52 and 43 %, respectively (p < 0.001). Inhibition of RhoA and Rho kinase also significantly downregulated cPLA₂ activation by 66 and 60 %, respectively (p < 0.01). Furthermore, inhibition of RhoA and Rho kinase reduced the release of arachidonic acid, a downstream substrate of cPLA₂. The immunofluorescence staining showed that ROCK₁ or ROCK₂, two isoforms of Rho kinase, was co-localized with cPLA₂ in neuronal cytoplasm. Interestingly, co-immunoprecipitation (Co-IP) assay showed that ROCK₁ or ROCK₂ bonded directly with cPLA₂ and phospho-cPLA₂. When the Rho kinase inhibitor Y27632 was applied in mice with T10 contusion injury, it significantly decreased cPLA₂ activation and expression and reduced injury-induced apoptosis at and close to the lesion site. Taken together, our results reveal a novel mechanism of RhoA/Rho kinase-mediated neuronal death through regulating cPLA₂ activation.

Thermal nociception using a modified Hargreaves method in primates and humans

Nociception is an important protective mechanism. The Hargreaves method, which involves measuring withdrawal latency following thermal stimulation to Thermal nociception using a modified Hargreaves method in primates and humans the paw, is commonly used to measure pain thresholds in rodents. We modified this technique to measure pain thresholds in monkeys and humans. The modified Hargreaves method was used to quantitate pain sensitivity in eight normal rhesus monkeys, 55 human volunteers, and 12 patients with spinal cord or cauda equina lesions. Thermal stimulation was delivered at 80% of maximum output, and the duration of the stimulation was set at a maximum of 10 seconds to avoid skin injury. The following withdrawal latencies were recorded: 2.7 ± 0.12 seconds in volunteers and 3.4 ± 0.35 seconds in neurologically intact monkeys (p>0.05). Patients with spinal cord or cauda equina lesions showed significantly increased latencies (p<0.001). The modified Hargreaves technique is a safe and reliable method that can provide a validated measure of physiological pain sensation.

Overexpression of microRNA-24 increases the sensitivity to paclitaxel in drug-resistant breast carcinoma cell lines via targeting ABCB9

Paclitaxel has been widely used in the treatment of breast cancer. However, the development of drug resistance often increases the failure of chemotherapy. Growing evidence has reported the significant role of microRNAs (miRs) in drug resistance. The present study identified that miR-24 was significantly downregulated in paclitaxel-resistant (PR) breast cancer patients and in MCF-7/PR human breast carcinoma cells, and that overexpression of miR-24 could increase the effect of paclitaxel on drug-resistant breast carcinoma cells. Furthermore, miR-24 could directly bind to the 3′-untranslated region of ATP binding cassette B9 to downregulate its expression, thereby reducing drug transportation and improving the anti-tumor effect of paclitaxel on breast cancer cells. In vivo experiments also demonstrated that overexpression of miR-24 could increase the sensitivity of drug-resistant MCF-7 cells to paclitaxel. In conclusion, the present results suggested a novel function for miR-24 in reducing paclitaxel resistance in breast cancer, which may be of important clinical significance.