Does exercise have a protective effect on cognitive function under hypoxia? A systematic review with meta-analysis

OBJECTIVE

This study aimed to examine (1) the independent effects of hypoxia on cognitive function and (2) the effects of exercise on cognition while under hypoxia.

METHODS

Design: Systematic review with meta-analysis.

DATA SOURCES

PubMed, Scopus, Web of Science, PsychInfo, and SPORTDiscus were searched. Eligibility criteria for selecting studies: randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered (Aim 2), as were studies investigating the effects of hypoxia on cognition (Aim 1).

RESULTS

In total, 18 studies met our inclusionary criteria for the systematic review, and 12 studies were meta-analyzed. Exposure to hypoxia impaired attentional ability (standardized mean difference (SMD) = -0.4), executive function (SMD = -0.18), and memory function (SMD = -0.26), but not information processing (SMD = 0.27). Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement (SMD = 0.3, 95% confidence interval: 0.14 - 0.45, I² = 54%, p < 0.001). Various characteristics (e.g., age, cognitive task type, exercise type, exercise intensity, training type, and hypoxia level) moderated the effects of hypoxia and exercise on cognitive function.

CONCLUSION

Exercise during exposure to hypoxia improves cognitive function. This association appears to be moderated by individual and exercise/hypoxia-related characteristics.

Impact of medication adherence to dual antiplatelet therapy on the long-term outcome of drug-eluting or bare-metal stents

Objective

In percutaneous coronary intervention, drug-eluting stent (DES) showed better clinical outcome compared to bare-metal stent (BMS) but mostly with different DAPT durations. This study investigated the clinical superiority of DES over BMS with regard to the medication adherence to dual antiplatelet therapy (DAPT).

Methods

We retrospectively enrolled all Koreans PCI patients in year 2011 (n=47,291). Medication adherence to DAPT was assessed by proportion of days covered (PDC) per 6 months. Analysis adjusted with the clinical propensity for receiving DES or BMS and DAPT PDC of the first 6 month was performed. Primary outcome was the 5-year major adverse clinical event (MACE) risk consisting all-cause death, revascularization, shock, or stroke.

Results

Patients with DES (n=46,356) showed higher PDC (78% versus 60%, p&lt;0.001) and lower MACE risk (39% versus 56%, p&lt;0.001) compared to patients with BMS (n=935). In the propensity-matched 1,868 patients, MACE risk was lower with DES than BMS (46% versus 54%, HR=0.80, 95% CI: 0.70–0.91, p&lt;0.001). Patients with good medication adherence (PDC ≥80%) showed much lower MACE risk compared to patients with PDC &lt;80% regardless of DES or BMS (HR=0.36, 95% CI: 0.30–0.44; HR=0.40, 95% CI: 0.33–0.48, p&lt;0.001, all). Patients with DES and PDC &lt;80% showed higher MACE risk compared to BMS with and PDC ≥80% (HR=1.30, 95% CI: 1.03–1.64, p=0.027).

Conclusions

Good medication adherence to DAPT in the first 6 month was prerequisite for better clinical outcome in both DES and BMS. DES with poor adherence to DAPT showed worse outcome compared with BMS with good adherence.

Impact of medication adherence to dual antiplatelet therapy.

Funding Acknowledgement

Type of funding source: None

Comparison of medication adherence between fixed-dose combination of angiotensin receptor blockers and statin and free-combination therapy

Background

Non-adherence to angiotensin receptor blockers (ARB) or statin is one of major reasons of insufficient treatment for patients with hyperlipidemia and hypertension. We investigated whether fixed-dose combination (FDC) of ARB and statin improved adherence compared to traditional free combination (FC).

Methods

In this retrospective nationwide cohort study, adherence of 128,369 patients who started ARB and stain including atorvastatin or rosuvastatin between July 2014 and June 2015 was investigated. Primary endpoint was proportion of days covered (PDC) per 180 days up to day 540. Good compliance defined by PDC≥80% and persistency rate defined by patients remaining on medication were also investigated.

Results

Patients were 62.9 years of mean age with 48.2% female gender. Compared to FC (N=90,759, 70.7%), FDC (N=37,610, 29.3%) showed higher PDC at day 180 (86% vs 70%), 360 (77% vs 62%), and 540 (74% vs 55%, p&lt;0.001, all). Frequency of patients with PDC≥80% was also higher in FDC compared to FC at day 180 (80.1% vs 51.8%), 360 (71.7% vs 54.2%), and 540 (69.2% vs 49.3%, p&lt;0.001, all). Persistency rate at day 540 was higher in FDC compared to FC (50.4% vs 27.3%, p&lt;0.001). The mean decline in PDC per 180 days were significantly lower in FDC compared to FC per 180 days (6.0% vs. 7.5%, p&lt;0.001).

Conclusions

In this real-world data analysis, FDC resulted in higher medication adherence and persistence compared to FC among patients who started both ARB and atorvastatin or rosuvastatin.

Persistence rate btw FDC and FC

Funding Acknowledgement

Type of funding source: None

Does Performance-Related Information Augment the Maximal Isometric Force in the Elbow Flexors?

The effects of different feedback conditions on the elbow flexors maximal voluntary isometric (MVIC) force were examined. In a single visit, twenty participants (10 males) were exposed to four conditions including, Visual only; (i.e., knowledge of results [VI]); Verbal encouragement (i.e., verbally stating pull, pull [VE]); VI and VE (VIVE); and no VI or VE (NOVIVE). Three, 5-s MVIC trials were completed for each condition. Separate 2 × 4 (sex × condition) repeated measures analyses of variance (ANOVA) were used to examine MVIC force, rate of force development (RFD₂₀₀), and rate of electromyography (EMG) rise (RER₂₀₀) for the 0-200-ms window. There was a significant main condition effect for MVIC force (p < 0.001). Significantly greater MVIC force was shown for VIVE compared to VE (p < 0.001) and NOVIVE (p = 0.002) conditions, and VI compared to VE (p = 0.011) and NOVIVE (p = 0.009) conditions. A significant sex × condition interaction (p = 0.036) was observed for RFD₂₀₀, with significantly (p = 0.003) greater RFD₂₀₀ in males compared to females, in the VI condition only. There were no significant differences in RFD₂₀₀ among condition for males (p = 0.033) or females (p = 0.194). There was a significant main effect for sex (p = 0.006) for RER₂₀₀, with significantly greater (p = 0.003) RER₂₀₀ (conditions merged) in males (mean ± standard deviation (SD): 422.99 ± 124.67%), compared to females (220.68 ± 134.01%). Here we suggest the importance of providing VI feedback alone, or in conjunction with VE, for the measurement of elbow flexion MVIC. Additionally, these results provide a foundational framework for future studies aiming to improve feedback modalities during training or rehabilitation.

Usefulness of computed tomography venography in gynecologic cancer patients with lower extremity edema

Lower extremity (LEx) edema is a common complication in gynecologic cancer patients. There are 2 main causes of edema in these patients such as deep vein thrombosis (DVT) and lymphedema. Early diagnosis and treatment of DVT are certainly important, but it is often difficult to evaluate proximal DVT by using ultrasound. The aim of this study is to demonstrate the usefulness of computed tomography venography of the lower extremity (CTV LEx) for the diagnosis of the DVT and investigate predictive factor of DVT in gynecologic cancer patients with LEx edema.The medical records of 415 gynecologic cancer patients who were referred to the department of rehabilitation medicine with LEx edema were retrospectively reviewed in this case-controlled study. We categorized CTV LEx findings as follows: DVT proximal to the inguinal ligament (inferior vena cava or iliac vein thrombosis) and DVT distal to the inguinal ligament (femoral, popliteal, or calf vein thrombosis). We also evaluated patient characteristics including D-dimer level. We analyzed the correlation of each factor with DVT frequency and used receiver operating characteristic curve analysis to determine the appropriate D-dimer threshold.Sixty-six patients were diagnosed with DVT; of them, 35 (53%) had DVT proximal to the inguinal ligament. Twenty-two patients were diagnosed with pulmonary embolism, of whom 15 had proximal DVT. Patients with proximal DVT tended to have pulmonary embolism (P < .001). Distal organ metastasis (odds ratio [OR], 2.88; P = .002) and a high D-dimer level (OR, 1.13; P = .001) were correlated with DVT.CTV LEx is a useful diagnostic tool for gynecologic cancer patients with LEx edema, particularly high-risk patients, that should be performed at the initial evaluation.

[Analysis on the cluster epidemic of coronavirus disease 2019 in Guangdong Province]

Objective: Analysis of clustering characteristics of coronavirus disease 2019 (COVID-19) in Guangdong Province. Methods: The COVID-19 cases in Guangdong Province onset from January 1 to February 29, 2020 were collected from Chinese information system for disease control and prevention and Emergency Public Reporting System. Obtain the epidemiological survey data of the cluster epidemic situation, and clarify the scale of cluster epidemic situation, the characteristics of the index cases, family and non-family subsequent cases. Calculate serial interval according to the onset time of the index cases and subsequent cases, secondary attack rate based on the close contacts tracking results, the characteristics of different cases in the clustered epidemic were compared. Results: A total of 283 cluster were collected, including 633 index cases, 239 subsequent cases. Families are mainly clustered, the total number involved in each cluster is in the range of 2-27, M (P₂₅, P₇₅) are 2.0 (2.0, 4.0). During January 15 to February 29, the secondary attack rate is 2.86% (239/8 363) in Guangdong Province, the family secondary attack rate was 4.84% (276/3 697), and the non-family secondary attack rate was 1.32% (61/4 632). According to the reporting trend of the number of cases in Guangdong Province, it can be divided into four stages, the rising stage, the high platform stage, the descending stage and the low level fluctuation period. The secondary attack rate of the four stages were 3.5% (140/3 987), 2.3% (55/2 399), 2.6% (37/1 435), 1.3% (7/542), respectively. The difference was statistically significant (P=0.003). Conclusion: COVID-19 cluster mainly occurs in families in Guangdong Province. The scale of the clustered epidemic was small; the serial interval was short; and the overall secondary attack rate was low.

Hierarchically Structured Laser-Induced Graphene for Enhanced Boiling on Flexible Substrates

Thermal management problems in high-power flexible electronics are exacerbated by the design complexity and requirement of stringent temperature control to prevent skin burns. Thus, effective heat dissipation methods applicable to flexible electronics on polymer substrates are an essential device design component. Accordingly, this study investigates the pool boiling heat transfer characteristics and potential enhancements, enabled by laser-induced graphene (LIG), which is both highly porous and bendable. Patterned LIG with a mesh spacing of 200 μm was formed on flexible polyimide substrates by laser direct writing, and the resulting surfaces exhibited enhanced heat transfer characteristics. Pool boiling experiments were conducted with an FC-72 working fluid to investigate the heat removal capability of LIG, and its performance was further improved by separating the liquid supply passages from the vapor escape routes. Overall, the inclusion of LIG resulted in a 2- to 3-fold increase in both the critical heat flux (33.6 W/cm²) and heat transfer coefficient (7.6 kW/(m²·K)), compared to pristine polyimide films.

The role of small leucine zipper protein in osteoclastogenesis and its involvement in bone remodeling

Bone remodeling is critical to maintain the quality of bone tissues and to heal bone tissue injury. Osteoclasts and osteoblasts are special types of cells involved in this event. In particular, the resorption activity of mature osteoclasts is required for the formation of new bones. Human small leucine zipper protein (sLZIP) is known to induce the osteoblast differentiation of mesenchymal stem cells. However, the roles of sLZIP in osteoclast differentiation and bone remodeling have not been explored. In this study, we investigated the roles of sLZIP in regulating osteoclast formation and in the bone remodeling process using sLZIP transgenic (TG) mice. Tibiae from sLZIP TG mice contained more osteoclasts than those from wild type (WT) mice. Bone marrow-derived macrophages (BMM) from sLZIP TG mice showed increased differentiation into osteoclasts compared with BMM from WT mice. sLZIP bound to the promotor and induced the expression of nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1) and its target osteoclastogenic genes. To understand the role of sLZIP in bone remodeling, a bone-defect model was generated. Results of micro-CT scanning and histologic analysis demonstrated that sLZIP TG mice have faster bone formation during healing compared with WT mice. Notably, the soft callus around the defect area was replaced faster by hard callus in sLZIP TG mice than in WT mice. These findings suggest that sLZIP promotes osteoclast differentiation and plays an important role in bone remodeling.

Display of quintuple glucagon-like peptide 1 (28-36) nonapeptide on Bacillus subtilis spore for oral administration in the treatment of type 2 diabetes

AIMS

To develop an oral delivery system of glucagon-like peptide 1 (GLP-1) (28-36) for treating type-2 diabetes, B.S-GLP-1(28-36), a recombinant Bacillus subtilis spores transformed with a plasmid vector encoding five consecutive GLP-1 (28-36) nonapeptides with an enterokinase site was constructed.

METHODS AND RESULTS

GLP-1(28-36) nonapeptide was successfully expressed on the surface of B. subtilis spores and validated by Western blot and immunofluorescence. The therapeutic effect of oral administration of B.S-GLP-1(28-36) spores was evaluated in type 2 diabetic model mice. The efficacy of recombinant spores was examined for a period of 13 weeks after oral administration in diabetic mice. At the end of the sixth week, diabetic mice with oral administration of BS-GLP-1(28-36) spores showed decreased blood glucose levels from 2·4 × 10^{- 2}  mol l^-1 to 1·7 × 10^{- 2}  mol l^-1 . By the ninth week, the mean fasting blood glucose level in the experimental group was significantly lower than that in the control group 30 min after injection of pyruvate. At the end of the 10th week of oral administration, the blood glucose of the experimental group was significantly lower than that of the control group after intraperitoneal injection of glucose. By the 12th week, fasting blood glucose level and fasting insulin level were measured in all mice, the results showed that the recombinant spores increased the insulin sensitivity of mice.

CONCLUSIONS

The results of pathological observation showed that the recombinant spores also had a certain protective effect on the liver and islets of mice, and the content of GLP-1(28-36) in the pancreas of the experimental group was increased.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of this study revealed that GLP-1(28-36) nonapeptides can reduce blood glucose and play an important role in the treatment of type 2 diabetes.

Mechanoadaptive strain and functional osseointegration of dental implants in rats

Spatiotemporal implant-bone biomechanics and mechanoadaptive strains in peri-implant tissue are poorly understood. Physical and chemical characteristics of an implant-bone complex (IBC) were correlated in three-dimensional space (along the length and around a dental implant) to gather insights into time related integration of the implant with the cortical portion of a jaw bone in a rat. Rats (N = 9) were divided into three experimental groups with three rats per time point; 3-, 11-, and 24-day. All rats were fed crumbled hard pellets mixed with water (soft-food diet) for the first 3 days followed by a hard-food diet with intact hard-food pellets (groups of 11- and 24-day only). Biomechanics of the IBCs harvested from rats at each time point was evaluated by performing mechanical testing in situ in tandem with X-ray imaging. The effect of physical association (contact area) of a loaded implant with adapting peri-implant tissue, and resulting strain within was mapped by using digital volume correlation (DVC) technique. The IBC stiffness at respective time points was correlated with mechanical strain in peri-implant tissue. Results illustrated that IBC stiffness at 11-day was lower than that observed at 3-day. However, at 24-day, IBC stiffness recovered to that which was observed at 3-day. Correlative microscopy and spectroscopy illustrated that the lower IBC stiffness was constituted by softer and less mineralized peri-implant tissue that contained varying expressions of osteoconductive elements. Lower IBC stiffness observed at 11-day was constituted by less mineralized peri-implant tissue with osteoconductive elements that included phosphorus (P) which was co-localized with higher expression of zinc (Zn), and lower expression of calcium (Ca). Higher IBC stiffness at 24-day was constituted by mineralized peri-implant tissue with higher expressions of osteoconductive elements including Ca and P, and lower expressions of Zn. These spatiotemporal correlative maps of peri-implant tissue architecture, heterogeneous distribution of mineral density, and elemental colocalization underscore mechanoadaptive physicochemical properties of peri-implant tissue that facilitate functional osseointegration of an implant. These results provided insights into 1) plausible "prescription" of mechanical loads as an osteoinductive "therapeutic dose" to encourage osteoconductive elements in the peri-implant tissue that would facilitate functional osseointegration of the implant; 2) a "critical temporal window" between 3 and 11 days, and perhaps it is this acute phase during which key candidate regenerative molecules can be harnessed to accelerate osseointegration of an implant under load.

Severe cytomegalovirus gastritis after pembrolizumab in a patient with melanoma

Immunotherapy has emerged as a standard of cancer treatment, with an increasing number of indications. Recently, opportunistic infections have been reported in several cases in which immunotherapy has led to an increased susceptibility to infection. The present case is the first report of cytomegalovirus (cmv) gastritis occurring in a patient with melanoma during immunotherapy without immune-related adverse events (iraes) and without the use of immunosuppressant agents. A 43-year-old woman presented with stage iii malignant melanoma. She underwent wide excision of skin, with lymph node dissection, and she started immunotherapy with a 3-week cycle of pembrolizumab. The patient demonstrated stable disease response, and no iraes were observed during her initial treatment courses. However, after the 9th treatment cycle, she began to experience epigastric pain that worsened significantly, requiring a visit to the emergency centre. Imaging by computed tomography (ct) and integrated positron-emission tomography/ct revealed severe diffuse gastroduodenitis with acute pancreatitis. Esophagogastroduodenoscopy showed diffuse oozing, hemorrhagic, edematous, and exfoliative mucosa involving the entire gastric wall, defined as acute hemorrhagic gastritis. Biopsies of the gastric wall revealed cmv infection. Those findings were consistent with a diagnosis of cmv gastritis, and the patient received antiviral therapy with ganciclovir. After treatment, she recovered enough to resume immunotherapy. This case report presents a rare occurrence of cmv gastritis related to immunotherapy. As more patients are treated with immunotherapy, incidences of cmv infections are expected to increase; a high index of clinical suspicion is therefore needed in symptomatic patients.

Data on biomechanics and elemental maps of dental implant-bone complexes in rats

Implant-bone biomechanics and mechanoadaptation of peri‑implant tissue in space (around and along the length of an implant) and time (3-, 11-, and 24-day following implantation) are important for functional osseointegration of dental implants. Spatiotemporal shifts in biomechanics of implant-bone complex in rat maxillae were correlated with maximum (tensile) and minimum (compressive) principal strain profiles in peri‑implant tissue using a hybrid model; biomechanics in situ paired with digital volume correlation. Spatiotemporal changes in elemental counts and their association with mineral density of the peri‑implant tissue were mapped using electron dispersive X-ray and X-ray fluorescence microprobe techniques. Data provided within are related to biomechanical testing of an implant-bone complex in situ. Data also highlight the power of correlating elemental colocalization with tension and compression regions of the peri‑implant tissues to explain spatiotemporal mechanoadaptation of implant-bone complexes. Further interpretation of data is provided in "Mechanoadaptive Strain and Functional Osseointegration of Dental Implants in Rats [1]."

Commissioning and beam characterization of the first gantry-mounted accelerator pencil beam scanning proton system

PURPOSE

To present and discuss beam characteristics and commissioning process of the first gantry-mounted accelerator single room pencil beam scanning (PBS) proton system.

METHODS

The Mevion HYPERSCAN employs a design configuration with a synchrocyclotron mounted on the gantry to eliminate the traditional beamline and a nozzle that contains the dosimetry monitoring chambers, the energy modulator (Energy Selector (ES)), and an Adaptive Aperture (AA). To characterize the beam, we measured the integrated depth dose (IDDs) for 12 energies, from highest energy of 227 MeV down to 28 MeV with a range difference ~ 2 cm between the adjacent energies, using a large radius Bragg peak chamber; single-spot profiles in air at five locations along the beam central axis using radiochromic EBT3 film and cross compared with a scintillation detector; and determined the output using a densely packed spot map. To access the performance of AA, we measured interleaf leakage and the penumbra reduction effect. Monte Carlo simulation using TOPAS was performed to study spot size variation along the beam path, beam divergence, and energy spectrum.

RESULTS

This proton system is calibrated to deliver 1 Gy dose at 5 cm depth in water using the highest beam energy by delivering 1 MU/spot to a 10 × 10 cm² map with a 2.5 mm spot spacing. The spot size in air varies from 4 mm to 26 mm from 227 MeV to 28 MeV at the isocenter plane with the nozzle retracted 23.6 cm from isocenter. The beam divergence of 28 MeV beam is ~ 52.7 mrad, which is nearly 22 times that of 227 MeV proton beam. The binary design of the ES has resulted in shifts of the effective SSD toward the isocenter as the energy is modulated lower. The peaks of IDD curves have a constant 80%-80% width of 8.4 mm at all energies. The interleaf leakage of the AA is less than 1.5% at the highest energy; and the AA can reduce the penumbra by 2 mm to 13 mm for the 227 and 28 MeV energies at isocenter plane in air.

CONCLUSIONS

The unique design of the HYPERSCAN proton system has yielded beam characteristics significantly different from that of other proton systems in terms of the Bragg peak shapes, spot sizes, and the penumbra sharpening effect of the AA. The combination of the ES and AA has made PBS implementation possible without using beam transport line and range shifter devices. Different considerations may be required in treatment planning optimization to account for different design and beam characteristics.

Combined effects of acute exercise and hypoxia on memory

No previous studies have evaluated the potential combined effects of acute exercise and acute hypoxia exposure on memory function, which was the purpose of this study. Twenty-five participants (Mage = 21.2 years) completed two laboratory visits in a counterbalanced order, involving 1) acute exercise (a 20-min bout of moderate-intensity exercise) and then 30 min of exposure to hypoxia (FIO2 = 0.12), and 2) exposure to hypoxia alone (FIO2 = 0.12) for 30 min. Following this, participants completed a cued-recall and memory interference task (AB/AC paradigm), assessing cued-recall memory (recall 1 and recall 2) and memory interference (proactive and retroactive interference). For cued-recall memory, we observed a significant main effect for condition, with Exercise + Hypoxia condition having significantly greater cued-recall performance than Hypoxia alone. Memory interference did not differ as a function of the experimental condition. This experiment demonstrates that engaging in an acute bout of exercise prior to acute hypoxia exposure had an additive effect in enhancing cued-recall memory performance.

Short communication: Dietary bovine milk-derived exosomes improve bone health in an osteoporosis-induced mouse model

Osteoporosis is a systemic skeletal disease characterized by low bone mass and micro-architectural deterioration of bone tissue, with a consequent increase in bone fragility and fracture susceptibility. In an aged society with increased life expectancy, the incidence rate of osteoporosis is also rapidly increasing. Inadequate nutrition may negatively influence bone metabolism. Recently, many studies have investigated the functionality of milk-derived exosomes, which play important roles in cell-to-cell communication. However, there are few reports of how milk-derived exosomes influence osteoblast proliferation and differentiation. Here, we determined whether bovine colostrum-derived exosomes promote anti-osteoporosis in vitro and in vivo. Tartrate-resistant acid phosphatase-stained cells were significantly inhibited in Raw264.7 cells treated with exosomes, indicating reduced osteoclast differentiation. We induced osteoporosis in mice using glucocorticoid pellets after orally administering exosomes for 2 mo. Interestingly, the bone mineral density of exosome-fed mouse groups was significantly improved compared with the glucocorticoid-induced osteoporosis group without exosome treatment. In addition, Lactobacillus were decreased in the gut microbiota community of osteoporosis-induced mice, but the gut microbiota community composition was effectively restored by exosome intake. Taken together, we propose that exosomes isolated from bovine colostrum could be a potential candidate for osteoporosis prevention, bone remodeling improvement, and inhibition of bone resorption. To our knowledge, this is the first time that a protective effect of milk exosomes against osteoporosis has been demonstrated in vivo. Our results strongly suggest that bovine colostrum exosomes might be used as a prophylaxis to prevent the onset of osteoporosis. Indeed, our results offer promising alternative strategies in the nutritional management of age-related bone complications.