慢性肾脏病患者蛋白质-能量消耗研究新进展

蛋白质-能量消耗在慢性肾脏病患者中发病率较高,临床上主要表现为饮食摄入、生化指标、体重指数、肌肉质量等方面的异常,其发病机制非常复杂,跟摄入不足、炎症、代谢性酸中毒、激素水平紊乱、透析相关因素等有关,严重影响透析患者的预后,因此早期发现、诊断和防治显得非常重要,将营养评估列入慢性肾脏病患者诊疗的日常工作当中,并对照诊断标准,及早诊断和采取各种措施防治蛋白质-能量消耗,最终提高慢性肾脏病患者的预后和生存率.本文对慢性肾脏病引起的蛋白质-能量消耗流行病学特点、发病机理、评估方式、治疗及干预措施等进行阐述.     

Experimental Wear Behavior Analysis of Coated Spindle Hook Teeth under Real Harvesting Work Conditions

This study aimed to investigate the wear failure changes of spindle hook teeth and the reasons for such failure during field work. Spindle samples were obtained from a fixed position of the spindle bar under different field picking area conditions and combined with the spatial distribution characteristics of cotton bolls in Xinjiang. After cutting a spindle sample, a scanning electron microscope and an energy spectrum analyzer were used to characterize the micromorphology and element composition of the hook tooth surface and cross section under different working area conditions. The wear parameters of the hook teeth were then extracted. The results showed that the thickness of the coating on the surface of the hook tooth used in this study was between 66.1 µm and 74.4 µm. The major chemical element was chromium, with a small amount of nickel. During the field picking process, failure of the coating on the surface of the hook teeth initially appeared on the tooth tip and tooth edge, and then spread to the entire hook tooth surface. The wear failure of the hook teeth resulted from abrasive wear, oxidative wear, and fatigue peeling. As the picking area increased, the wear area of the hook teeth increased exponentially, while the wear width increased linearly. When the field picking area reached 533.33 ha, the maximum change rate of the wear area was 2.33 × 10³ µm²/ha, and the wear width was 1.84 µm/ha. During field work, the thickness of the coating decreased from the cutting surface to the tooth edge, and the wear rate gradually increased. The wear rate at Position 1 was the slowest, at 0.01 µm/ha, and the wear rate at Position 5 was the fastest, at 0.25 µm/ha.     

Wire-Feeding Laser Welding of Copper/Stainless Steel Using Different Filler Metals

Ni-based filler metal and Ni-Cu-based filler metal were used to obtain copper/stainless steel (Cu/SS) joints through wire-feeding laser welding. Along the SS/weld interface, there exist different grain sizes (from coarse columnar grains to fine equiaxed grains). The heat affected zone (HAZ) on the copper side consisted of two areas with different grain sizes and the size of the grain in the Cu-HAZ of the Ni-Cu-based filled joint was much smaller than that of the Ni-based filled joint. Our results showed that grain refinement at the copper/weld (Cu/weld) interface of the Ni-Cu-based filled joint was observed through high-resolution electron backscattered diffraction (EBSD). There was a hardness elevation at the Cu/weld interface of the Ni-Cu-based filled joint due to the grain refinement on the weld of the copper side. The maximum tensile strength of the Ni-Cu-based filled joint was obtained and reached 91.2% of the tensile strength of the copper base metal (Cu-BM). Joints in this study were observed to fracture in a ductile mode. Furthermore, the Ni-Cu-based filled joint exhibited a higher plastic deformation, which was primarily caused by the large deformation of the weld zone and the large deformation of the Cu-BM due to the high plasticity of the weld, which alleviated the stress concentration, as indicated by 2D-digital image correlation (DIC) test results.     

Association of the Non-Alcoholic Fatty Liver Disease Fibrosis Score with subclinical myocardial remodeling in patients with type 2 diabetes: A cross-sectional study in China

Aims/IntroductionNon‐alcoholic fatty liver disease, especially with liver fibrosis, is associated with cardiovascular diseases. The Non‐Alcoholic Fatty Liver Disease Fibrosis Score (NFS), a non‐invasive marker of advanced fibrosis, was found to be associated with cardiovascular diseases in different populations. The aim of the present study was to determine whether the NFS is associated with subclinical myocardial remodeling in type 2 diabetes patients.Materials and MethodsA cross‐sectional study was carried out in type 2 diabetes patients. The NFS derived from available parameters was calculated, and the participants were divided according to the quartiles of the NFS and grades of the NFS (low, intermediate and high). Fibrosis‐4 and Aspartate Aminotransferase to Platelet Ratio Index, another two liver fibrosis scores, were also calculated. Subclinical myocardial remodeling was examined by echocardiography, and its associations with NFS, Fibrosis‐4 and Aspartate Aminotransferase to Platelet Ratio Index were analyzed.ResultsA total of 1,878 type 2 diabetes patients were enrolled in the present study. The NFS was independently associated with sex, age, body mass index, low‐density lipoprotein cholesterol and glycated hemoglobin in type 2 diabetes patients. Parameters of subclinical myocardial remodeling including left atrial dimension, interventricular septum thickness, left ventricular end‐diastolic diameter, left ventricular end‐systolic diameter, left ventricular posterior wall thickness (LVPWT) and left ventricular mass index were all gradually increased with the increment of the NFS. Linear regression analysis further showed that the NFS was positively associated with left atrial dimension, interventricular septum thickness, left ventricular end‐diastolic diameter, left ventricular end‐systolic diameter, LVPWT and left ventricular mass index after adjustment for the confounding factors. Similarly, Fibrosis‐4 was associated with left atrial dimension, interventricular septum thickness, LVPWT and left ventricular mass index. In contrast, the Aspartate Aminotransferase to Platelet Ratio Index was only associated with LVPWT.ConclusionsNon‐invasive liver fibrosis scores, especially the NFS, are independently associated with subclinical myocardial remodeling in type 2 diabetes patients.     

Effect of vancomycin loading dose on clinical outcome in critically ill patients with methicillin-resistant Staphylococcus aureus pneumonia

BackgroundVancomycin is the treatment of choice for serious methicillin-resistant Staphylococcus aureus (MRSA) infections. Current guidelines recommend giving an initial loading dose (LD) of 25–30 mg/kg to rapidly increase the serum concentration. However, high-quality evidence for the clinical benefit of LD is lacking. Herein, we aim to examine the association between vancomycin LD and clinical outcome.MethodsA retrospective cohort study was conducted on adult patients treated for MRSA pneumonia with vancomycin in medical intensive care units from April 2016 to August 2018. MRSA pneumonia was defined by the Centers for Disease Control and National Healthcare Safety Network definition. The primary outcome was the clinical cure of pneumonia. Secondary outcome measures included time to pharmacokinetic (PK) target attainment, microbiological cure, acute kidney injury, and all-cause mortality.ResultsA total of 81 patients were included; of these 22 (27.2%) received LD. The mean initial dose was significantly higher in the LD group. Clinical cure was similar in both groups (68.2% vs. 66.1% in the LD and non-LD groups, respectively; P=0.860). No significant difference was observed in the microbiological cure, all-cause mortality, and incidence of acute kidney injury. Furthermore, no difference was observed in terms of time to PK target attainment (69.2 vs. 63.4 h in the LD and non-LD groups, respectively; P=0.624). Vancomycin minimum inhibitory concentration of <2 mg/L was identified as an independent predictive factor for clinical cure in multivariable analysis, whereas vancomycin LD was not.ConclusionsInitial LD is not associated with better clinical outcome or rapid pharmacological target attainment in critically ill patients with MRSA pneumonia. Further studies are warranted to provide better evidence for this widely recommended practice.     

A simple fluorescent assay for cyromazine detection in raw milk by using CYR-stabilized G-quadruplex formation

A rapid biosensor for the detection of cyromazine in milk is reported based on a fluorescence quenching result. When an FAM labelled G-rich ssDNA Tcy2 is treated with cyromazine, it can form a G-quadruplex-CYR complex and cause a change in fluorescence. As a result, the presence of cyromazine can be determined by fluorescence quenching. This sensor is selective for the detection of cyromazine in raw milk and has a limit of detection of 0.68 ppb and a detection range from 0 to 200 ppb.

A rapid biosensor for the detection of cyromazine in milk is reported based on a fluorescence quenching result.     

Managing pasireotide-associated hyperglycemia: a randomized,open-label,Phase IV study

Purpose

Pasireotide is an effective treatment for acromegaly and Cushing’s disease, although treatment-emergent hyperglycemia can occur. The objective of this study was to assess incretin-based therapy versus insulin for managing pasireotide-associated hyperglycemia uncontrolled by metformin/other permitted oral antidiabetic drugs.

Methods

Multicenter, randomized, open-label, Phase IV study comprising a core phase (≤?16-week pre-randomization period followed by 16-week randomized treatment period) and optional extension (ClinicalTrials.gov ID: NCT02060383). Adults with acromegaly (n?=?190) or Cushing’s disease (n?=?59) received long-acting (starting 40 mg IM/28 days) or subcutaneous pasireotide (starting 600 µg bid), respectively. Patients with increased fasting plasma glucose (≥?126 mg/dL on three consecutive days) during the 16-week pre-randomization period despite metformin/other oral antidiabetic drugs were randomized 1:1 to open-label incretin-based therapy (sitagliptin followed by liraglutide) or insulin for another 16 weeks. The primary objective was to evaluate the difference in mean change in HbA_1c from randomization to end of core phase between incretin-based therapy and insulin treatment arms.

Results

Eighty-one (32.5%) patients were randomized to incretin-based therapy (n?=?38 received sitagliptin, n?=?28 subsequently switched to liraglutide; n?=?12 received insulin as rescue therapy) or insulin (n?=?43). Adjusted mean change in HbA_1c between treatment arms was – 0.28% (95% CI – 0.63, 0.08) in favor of incretin-based therapy. The most common AE other than hyperglycemia was diarrhea (incretin-based therapy, 28.9%; insulin, 30.2%). Forty-six (18.5%) patients were managed on metformin (n?=?43)/other OAD (n?=?3), 103 (41.4%) patients did not require any oral antidiabetic drugs and 19 patients (7.6%) were receiving insulin at baseline and were not randomized.

Conclusion

Many patients receiving pasireotide do not develop hyperglycemia requiring oral antidiabetic drugs. Metformin is an effective initial treatment, followed by incretin-based therapy if needed.

ClinicalTrials.gov ID: NCT02060383.

     

Validating respiratory index of auto-titrating positive airway pressure device with polysomnography

Purpose

Positive airway pressure (PAP) devices have been widely used as the first line of treatment in obstructive sleep apnea (OSA). Most advanced PAP devices support the estimation of respiratory index (RI) using the patient’s mask airflow. In addition to the compliance factor for PAP device use, which is important for monitoring patient sleep health, RI is also becoming important for monitoring. However, there are few reports that validate RI of a PAP device with polysomnography.

Methods

Between January 2015 and December 2017, 50 participants were enrolled who were diagnosed with OSA and prescribed auto-titration PAP (APAP) devices. The RIs of participants were measured at night using APAP devices, concurrently with electroencephalography, respiratory inductance plethysmography sensors, and other polysomnographic sensors in a sleep laboratory. The respiratory-related data of APAP were prospectively analyzed with the manually scored polysomnographic data.

Results

The apnea-hypopnea index and apnea index showed a statistically close relationship between the auto-scored respiratory data from the APAP device and the manually scored respiratory data from polysomnographic sensors. Obstructive apnea and central apnea indices showed relatively low correlations. The differences between the auto-scored RI and manually scored RI were influenced by BMI, waist circumference, weight, oxygen saturation, and respiratory distress indices of diagnostic polysomnographic factors.

Conclusions

The RIs of APAP devices have a tendency to be underestimated or mismatched when compared with polysomnography. Sleep specialists are advised to consider additional anthropometric and diagnostic factors to account for these differences during PAP treatment.

     

Atrial involvement and progression of sinus node dysfunction in non-senile patients: evidences from electroanatomic mapping and long-term follow-up

Purpose

Sinus node inability or conduction disorders of its surrounding atrial myocardium cause sinus node dysfunction (SND). This study aimed to characterize right atrium (RA) substrates and long-term atrial lead performance after pacemaker implantation in non-senile SND patients.

Methods

Eighteen SND patients (53.3?±?9.6 years) controlled by 18 age-matched supraventricular tachycardia patients were consecutively enrolled. The P-wave amplitude (PWA) and P-wave duration (PWD) were measured on surface electrocardiography. Electroanatomic mapping was conducted to assess the bipolar voltage, complex signals, volume, and activation time of RA. Pacemaker implantation was performed in SND patients after mapping.

Results

Compared with controls, SND patients showed significant PWA reduction (0.13?±?0.02 vs. 0.16?±?0.04 mV, p?=?0.017) and PWD prolongation (120.8?±?15.2 vs. 105.2?±?8.6 ms, p?=?0.001). The RA endocardial voltage was lower (1.56?±?0.78 vs. 2.57?±?0.55 mV, p?<?0.001) and activation time was longer (112.1?±?14.9 vs. 90.8?±?12.4 ms, p?<?0.001) in the study group. Atrial lead was anchored at the lower atrial septum in one patient and failed in another due to extensive atrial scarring. During a median follow-up of 86 (57–88) months, one patient lost atrial capturing, and overall atrial sensing was significantly decreased (2.44?±?1.16 vs. 1.87?±?1.01 mV, p?=?0.003).

Conclusions

Atrial involvement was proved and the process was progressive in non-senile SND patients, as demonstrated by diffused RA lower voltage, slower conduction, and the decrease of the atrial lead sensing.