Oxidative stress mediates the impact of heatwaves on survival, growth and immune status in a lizard.

Climate change often includes increases in the occurrence of extreme environmental events. Among these, heatwaves affect the pace of life and performance of wildlife, particularly ectothermic animals, owing to their low thermoregulatory abilities. However, the underlying mechanisms by which this occurs remain unclear. Evidence shows that heatwaves alter the redox balance of ectotherms, and oxidative stress is a major mediator of life-history trade-offs. Therefore, oxidative stress may mediate the effect of extreme thermal conditions on the life histories of ectotherms. To test this hypothesis, a 2 × 2 experiment was conducted to manipulate the redox balance (through a mitochondrial uncoupler that alleviates oxidative stress) of the desert toad-headed agama (Phrynocephalus przewalskii) exposed to heatwave conditions. We recorded lizard growth and survival rates and quantified their redox and immune statuses. In control lizards (unmanipulated redox balance), heatwave conditions decreased growth and survival and induced oxidative damage and immune responses. By contrast, lizards with alleviated oxidative stress showed close-to-normal growth, survival, and immune status when challenged with heatwaves. These results provide mechanistic insight into the role of oxidative stress in mediating the effects of extreme temperatures on ectothermic vertebrates, which may have major eco-evolutionary implications.

Telomere length, oxidative stress and their links with growth and survival in a lizard facing climate warming.

Higher temperatures enhance ectothermic metabolism and development, which can reduce individual health and life expectancy, and therefore increase their vulnerability to climate warming. However, the mechanistic causes and consequences of such a temperature-driven impact remain unclear. Our study aimed to address two questions: (1) does climate warming alter early-life growth and physiology, and, if so, what are the associated carry-over effects in terms of reduced survival, increased oxidative stress and telomere shortening? (2) can oxidative stress and telomere dynamics at early life stages predict the effect of climate warming on individual survival? To answer these questions, we conducted a longitudinal experiment under semi-natural conditions where we exposed multiocellated racerunner (Eremias multiocellata) to warming conditions from juvenile to adult stages. We found that exposure to climate warming enhanced growth rates, induced oxidative stress, and shortened telomere length of juvenile lizards. Warming conditions did not induce carry-over effects in terms of altered growth rate or physiology but resulted in increased mortality risk in the later life. Intriguingly, telomere shortening in young individuals was associated with mortality risk later in life. This study improves our mechanistic understanding of how global warming impacts on ectotherms' life-history traits, which encourages the inclusion of physiological information in assessing species vulnerability to climate change.

Application of double-stent assisted coil embolization in intracranial vertebral artery dissecting aneurysms with mass effect.

BACKGROUND: Unruptured intracranial vertebral artery dissecting aneurysms (IVADAs) with mass effect have an extremely poor natural course, and treatment of these aneurysms remains a challenge for endovascular and surgical strategies. The aim of this study was to analyze the role of double-stent-assisted coil embolization in preventing rupture and bleeding of intracranial vertebral artery dissecting aneurysm with brainstem compression by reducing mass effect and preventing the recurrence of the aneurysm. METHODS: A total of 25 patients (mean age, 56.04±13.0 years) with unruptured IVADAs with mass effect received dual-stent-assisted coil embolization. The baseline characteristics, the change of aneurysm size on MR, the rate of retreatment, and the improvement rate of clinical symptoms and signs were analyzed retrospectively. RESULTS: All patients completed the surgical procedures successfully. No aneurysm bleeding or perforating artery occlusion occurred during the perioperative and follow-up periods. The initial maximum diameter of the aneurysm on MR was 17.5±3.6 mm. One year after treatment, the maximum diameter of the aneurysm on MR was 15.8±4.9 mm. The reduction rate of the maximum diameter of the aneurysm was 10.7±12.7%. The change of the maximum diameter before and after treatment of aneurysm was statistically significant (P<0.001). In terms of the improvement rate of clinical symptoms, 15 cases were completely improved (60.0%), 6 cases were partially improved (24.0%), and the total clinical improvement rate was 84%. Four cases (16.0%) showed no improvement or even had aggravation of clinical symptoms. In 5 cases (20.0%), aneurysms recurred. Among 4 cases involving posterior inferior cerebellar artery origin, 3 cases had the recurrence (75%). 5 recurred cases were treated with single-stent-assisted coil embolization. No residual aneurysm and recurrence were found on the follow-up angiography. CONCLUSIONS: The double-stent-assisted coil embolization procedure is very safe and reliable. It can effectively prevent the aneurysm from continuing to grow and rupture and thereby reduce the clinical symptoms caused by the mass effect.

A detection of benzimidazole resistance-associated SNPs in the isotype-1 ß-tubulin gene in Haemonchus contortus from wild blue sheep (Pseudois nayaur) sympatric with sheep in Helan Mountains, China.

BACKGROUND: Benzimidazole (BZ) resistance is an increasingly serious problem due to the excessive use of this anthelmintic for controlling Haemonchus contortus, which is one of the major gastrointestinal nematodes infecting small ruminants worldwide. Three known single nucleotide polymorphisms (SNPs), F167Y (TAC), E198A (GCA) and F200Y (TAC), in the isotype-1 ß-tubulin gene of H. contortus are associated with BZ resistance. Comprehending the spread and origins of BZ resistance-associated SNPs has important implications for the control of this nematode. RESULTS: Twenty-seven adult H. contortus were harvested from wild blue sheep (Pseudois nayaur), small wild ruminants sympatric with domestic ruminants, inhabiting the Helan Mountains, China, to monitor the status of BZ resistance. In addition, 20 adult H. contortus from domestic sheep sympatric with this wild ruminant and 36 isotype-1 ß-tubulin haplotype sequences of H. contortus (two of these haplotypes, E198A3 and E198A4, possessed resistance-associated SNP E198A (GCA) from domestic ruminants in eight other geographical regions of China were used to further define the origins of BZ resistance-associated SNPs within the worms collected from blue sheep. The BZ resistance-associated SNP E198A was detected, whereas SNPs F167Y (TAC) and F200Y (TAC) were not found within the worms collected from blue sheep, and the frequency of homozygous resistant E198A (GCA) was 7.40%. The evolutionary tree and network showed consistent topologies for which there was no obvious boundary among the worms from the wild and domestic hosts, and two haplotypes (E198A1 and E198A2) possessing E198A from the wild blue sheep had two different independent origins. E198A1 had the same origin with E198A3 but E198A2 had a different origin with them. Population genetic analyses revealed a low level of Fst values (ranging from 0 to 0.19749) between all H. contortus worm groups in China. CONCLUSIONS: Results of the current study of the three BZ resistance-associated SNPs of H. contortus from wild blue sheep suggested that only E198A (GCA) was present within the worms collected from the wild ruminants and had multiple independent origins.

Comparison of Micro-Clamping Stent-Retriever Thrombectomy with Conventional Stent-Retriever Thrombectomy in Intracranial Large Vessel Embolism.

OBJECTIVE: To evaluate the effectiveness of micro-clamping stent-retriever thrombectomy (MSRT) in patients with acute ischemic stroke with intracranial large vessel embolism (ILVE), and compare it with that of conventional stent-retriever thrombectomy (CSRT). METHODS: We retrospectively evaluated 108 patients with ILVA treated by MSRT (n = 52) or CSRT (n = 56) from the 2 participating institutions between January 2016 and November 2017. The rates of successful (Modified Thrombolysis in Cerebral Infarction [mTICI] grade 2b or 3) and complete reperfusion (mTICI grade 3), time from guide catheter placement to reperfusion, rates of first-pass success, and the number of passes for reperfusion were compared between the MSRT and CSRT groups. RESULTS: The complete reperfusion (mTICI 3) rates by MSRT were significantly higher than those achieved with CSRT (78.8% [41/52] vs. 57.1% [32/56], respectively; P = 0.016). Successful reperfusion (mTICI 2b or 3) rates were 92.3% (48/52) in the MSRT group and 83.9% (47/56) in the CSRT groups (P = 0.181). The mean number of passes for reperfusion was significantly lower with MSRT compared with CSRT (1.5 ± 0.2 vs. 2.5 ± 0.5, respectively; P = 0.001). The first-pass success rates were significantly higher in the MSRT group than in the CSRT group (65.4% [34/52] vs. 28.6% [16/56]; P = 0.0001). The mean time from guide catheter placement to reperfusion was significantly shorter in the MSRT group (20.5 ± 6.6 minutes vs. 46.3 ± 7.6 minutes; P = 0.001). CONCLUSIONS: These findings suggest that the complete reperfusion rates and mechanical thrombectomy efficiency in patients with ILVE are better after MSRT compared with CSRT.

Thrombectomy Using "Clamping Embolus with Semi-Retrieval" Technique in Acute Ischemic Stroke.

BACKGROUND: Embolization of thrombus fragments in new or downstream vascular territories is a potential adverse event in neurothrombectomy, requiring additional repeated thrombectomy attempts. This study aims to describe technical results of the thrombectomy with clamping embolus technique (TCET) method in acute ischemic stroke. This study also aims to evaluate the efficiency of mechanical thrombectomy by TCET, and to compare it with conventional stent retriever thrombectomy (CSRT). MATERIALS AND METHODS: A retrospective analysis was performed in 52 consecutive patients treated between January 2015 and October 2016 for intracranial large vessel occlusion by stent retriever thrombectomy. Recanalization rates, procedure durations, and thrombectomy attempts were compared between the TCET and the CSRT groups. RESULTS: Successful recanalization (thrombolysis in cerebral infarction [TICI] 2b or 3) with TCET was achieved in 91.7% (22 of 24) versus 92.9% (26 of 28) in the CSRT group (P = .921). To preserve the restored patency of severely affected atherosclerotic intracranial vessels, 7 and 8 patients received angioplasty or stenting in the TCET and CSRT groups, respectively. In embolic cases, the number of thrombectomy attempts with TCET was significantly lower than that obtained with CSRT (1.7 ± .2 versus 2.6 ± .5, respectively; P = .001); the one-pass thrombectomy rate was significantly higher in the TCET group than in the CSRT-treated patients (58.8% versus 25.0%, respectively; P = .014). Procedure duration was significantly shorter by TCET than by CSRT (35.8 ± 5.8 minutes versus 55.5 ± 7.2 minutes, respectively; P = .001). CONCLUSIONS: The efficiency of mechanical thrombectomy by TCET in acute ischemic stroke might be improved compared with CSRT.

Genetic diversity of Haemonchus contortus isolated from sympatric wild blue sheep (Pseudois nayaur) and sheep in Helan Mountains, China.

BACKGROUND: Haemonchus contortus is known among parasitic nematodes as one of the major veterinary pathogens of small ruminants and results in great economic losses worldwide. Human activities, such as the sympatric grazing of wild with domestic animals, may place susceptible wildlife hosts at risk of increased prevalence and infection intensity with this common small ruminant parasite. Studies on phylogenetic factors of H. contortus should assist in defining the amount of the impact of anthropogenic factors on the extent of sharing of agents such as this nematode between domestic animals and wildlife. METHODS: H. contortus specimens (n = 57) were isolated from wild blue sheep (Pseudois nayaur) inhabiting Helan Mountains (HM), China and additional H. contortus specimens (n = 20) were isolated from domestic sheep that were grazed near the natural habitat of the blue sheep. Complete ITS2 (second internal transcribed spacer) sequences and partial sequences of the nad4 (nicotinamide dehydrogenase subunit 4 gene) gene were amplified to determine the sequence variations and population genetic diversities between these two populations. Also, 142 nad4 haplotype sequences of H. contortus from seven other geographical regions of China were retrieved from database to further examine the H. contortus population structure. RESULTS: Sequence analysis revealed 10 genotypes (ITS2) and 73 haplotypes (nad4) among the 77 specimens, with nucleotide diversities of 0.007 and 0.021, respectively, similar to previous studies in other countries, such as Pakistan, Malaysia and Yemen. Phylogenetic analyses (BI, MP, NJ) of nad4 sequences showed that there were no noticeable boundaries among H. contortus populations from different geographical origin and population genetic analyses revealed that most of the variation (94.21%) occurred within H. contortus populations. All phylogenetic analyses indicated that there was little genetic differentiation but a high degree of gene flow among the H. contortus populations among wild blue sheep and domestic ruminants in China. CONCLUSIONS: The current work is the first genetic characterization of H. contortus isolated from wild blue sheep in the Helan Mountains region. The results revealed a low genetic differentiation and high degree of gene flow between the H. contortus populations from sympatric wild blue sheep and domestic sheep, indicating regular cross-infection between the sympatrically reared ruminants.

Blood Oxygenation Level-Dependent Functional Magnetic Resonance Imaging in Early Days: Correlation between Passive Activation and Motor Recovery After Unilateral Striatocapsular Cerebral Infarction.

OBJECTIVE: This study aimed to investigate the correlation between the functional magnetic resonance imaging (fMRI) pattern and the motor function recovery of an affected limb during the passive movement of the affected limb at an early stage of the striatocapsular infarction (SCI). METHODS: A total of 17 patients with an acute stage of SCI and 3 healthy volunteers as controls were included in this study. fMRI scans of passive movement were performed on the affected limbs of stroke patients within 1 week of onset. Follow-ups were carried out for the motor functions of the affected limbs (before fMRI scan, 1 month, and 3 months after the scan). RESULTS: The control group showed that the activation was mainly located in the contralateral sensorimotor cortex (SMC) and the bilateral supplementary motor area (SMA). The fMRI scan region of interest for stroke patients can be divided into 3 types: type I includes mainly the affected side, bilateral SMC, and SMA with activation; type II includes SMC on the affected side and SMA with activation; type III includes only SMC on the affected side or M1 with activation. The recovery of type I patients was better and faster, while the recovery of type II patients was better but slower, but recovery of type III patients was poorer and slower. CONCLUSIONS: Multiple cortical activation patterns were noted during the passive movement of the affected limbs at an early stage of SCI, and a correlation was found between the different activation patterns and the clinical prognosis of patients.

Pontibacter amylolyticus sp. nov., isolated from a deep-sea sediment hydrothermal vent field.

A Gram-stain-negative, short rod-shaped bacterium, designated 9-2T, was isolated from a sediment sample collected from a hydrothermal vent field on the south-west Indian Ridge. It formed red colonies, produced carotenoid-like pigments and did not produce bacteriochlorophyll a. Strain 9-2T was positive for hydrolysis of DNA, gelatin and starch, but negative for hydrolysis of aesculin and Tween 60. The sole respiratory quinone was menaquinone-7 (MK-7). The main polar lipids consisted of phosphatidylethanolamine, one unidentified phospholipid and two unidentified polar lipids. The principal fatty acids (>5%) were summed feature 4 (iso-C17:1 I and/or anteiso-C17:1 B), iso-C15:0 and iso-C17:0 3-OH. The genomic DNA G+C content was 49.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 9-2T should be assigned to the genus Pontibacter. Levels of 16S rRNA gene sequence similarity between the new isolate and the type strains of Pontibacter species with validly published names were in the range 94.0-96.5%. On the basis of phenotypic and genotypic data, strain 9-2T represents a novel species of the genus Pontibacter, for which the name Pontibacter amylolyticus sp. nov. is proposed. The type strain is 9-2T (=CGMCC 1.12749T=JCM 19653T=MCCC 1K00278T).

Sufficient collateral blood supply from accessory middle cerebral artery in a patient with acute ischemic stroke.

We reported a case of acute embolic occlusion of the middle cerebral artery with a patent accessory middle cerebral artery. Because of the presence of sufficient collateral blood supply from the accessory middle cerebral artery, the patient only underwent transient ischemic attack and did not need endovascular treatment. There was mild infarction in the basal ganglia and temporal lobe, NIHSS score of the patient at discharge seven days after stroke onset was 0, and modified Rankin scale score at 90 days was 0.

Massive hemoptysis from pulmonary ligament artery supplying abnormal basal segments of the lower lobe.

BACKGROUND: Non-bronchial systemic arteries can be a significant source of massive hemoptysis in patients with marked pleural involvement. However, in some cases without pleural involvement, the pulmonary ligament artery (PLA) can also enter the abnormal lung parenchyma and be responsible for hemoptysis. PURPOSE: To discuss the factors influencing the development of a blood supply from the PLA in patients with hemoptysis. MATERIAL AND METHODS: Seventy-five consecutive patients who underwent bronchial artery embolization (BAE) for massive hemoptysis were evaluated between January 2006 and December 2011 retrospectively. Selective arteriography showed an enlarged and tortuous PLA in five patients. CT was done to determine the site and extent of the underlying diseases before BAE in all patients. Angiographic and CT images were analyzed to determine if there was a relationship between PLA supply and location of the underlying disease or mediastinal pleural involvement. RESULTS: The underlying lesions of six patients involved the basal segments of the lower lobe without marked mediastinal pleural thickening or adhesion, but diaphragmatic and lateral pleural thickening was observed in one case. Of these six patients, the PLA supplied blood to the lesions related to the hemoptysis in five patients. No patient with massive hemoptysis whose underlying lesions involved other segments of lung had a PLA supplying the lesions. CONCLUSION: Even though pleural involvement is absent, underlying lesions involving the basal segments of the lower lobe could be a good indicator that the PLA is the cause of bleeding in patients with massive hemoptysis.

Clinical value of whole-body magnetic resonance diffusion weighted imaging on detection of malignant metastases.

OBJECTIVE: To evaluate the value of whole-body diffusion weighted imaging (WB-DWI) on detection of malignant metastasis. METHODS: Forty-six patients with malignant tumors underwent WB-DWI examinations between April 2007 and August 2007 in our hospital. Before WB-DWI examination, the primary cancers of all the patients were confirmed by pathology, and the TNM-stage was assessed with conventional magnetic resonance imaging (MRI) or computed tomography (CT). WB-DWI was performed using short TI inversion recovery echo-planar imaging (STIR-EPI) sequence. Abnormal high signal intensities on WB-DWI were considered as metastases. The results of WB-DWI were compared with other imaging modalities. For the assessment of the diagnostic capability of WB-DWI, WB-DWI were compared with CT for demonstrating mediastinal lymph node metastases and lung metastases, and with conventional MRI for demonstrating metastases in other locations. RESULTS: WB-DWI demonstrated 143 focuses, 14 of which were diagnosed to be benign lesions in routine imaging. The number of bone metastases depicted on WB-DWI and routine imaging was 85 and 86; lymph node metastases was 17 and 18; liver metastases was 14 and 14; lung metastases was 4 and 8; and brain metastases was 6 and 8, respectively. WB-DWI failed to detect 12 metastatic lesions including 3 osteoplastic bone metastases, 4 lung metastases, 3 mediastinal lymph node metastases, and 2 brain metastases. Four metastatic lesions including 2 deltopectoral lymph nodes and 2 rib metastases were detected with WB-DWI alone, all of which evolved greatly during clinical follow-up for more than 6 months. WB-DWI had higher detection rates for metastatic lesions in liver, bone, and lymph nodes than those in lung and brain (chi2=30, P<0.001). CONCLUSIONS: WB-DWI could detect most of metastatic lesions that were diagnosed with conventional MRI and CT. The limitations of WB-DWI might be had high false-positive rate and low efficiency in detecting mediastinal lymph node, brain, and lung metastases.

Ultrafine needle CO2 splenoportography: a comparative investigation with transarterial portography and MR portography.

PURPOSE: To evaluate the safety and quality of CO2 splenoportography (CO2-SP) by comparison to 3-dimensional dynamic contrast-enhanced magnetic resonance portography (3D-DCE-MRP) and transarterial portography (TAP). MATERIALS AND METHODS: CO2-SP, 3D-DCE-MRP and TAP were performed within 3 days in 35 patients. CO2-SP was conducted with a 26G needle by puncture of spleen under fluoroscopy and/or ultrasound guidance. A fifty mm3 of CO2 was manually injected within 3s. The safety and the side effects of CO2-SP were assessed with a scoring system based on both the subjective feeling of patients questioned and the objective appearances of vital signs, electrocardiogram (ECG) and saturation of percutaneous blood oxygen (SpO2). The quality of the imaging was compared among the three groups using different methods by a scoring criterion based on visualization of the portal branches. RESULTS: Transient mild discomfortable reaction was present in 18 patients (51.4%). The scores measured for quality of portal vein branch visualization in the groups with CO2-SP, 3D-DCE-MRP and TAP were 226, 196 and 167, respectively (P<0.001, the higher of the scores, the better of the quality). The visibility of collateral veins was not significantly different amongst the three imaging techniques. CONCLUSION: Ultrafine needle CO2-SP is safe and minimally invasive. The quality of CO2-SP is better than that with 3D-DCE-MRP and TAP in terms of the visualizing portal vein branches.