单眼剥夺性弱视小鼠图形视觉诱发电位时间频率调制变化的研究

目的 探讨单眼剥夺性弱视小鼠图形视觉诱发电位（PVEP）的时间频率调制的变化。方法 生后26 d健 康C57BL/6J小鼠18只，随机均分为正常对照组和单眼剥夺（MD）组。MD组小鼠右眼眼睑行褥式缝合，5 d造成单眼 形觉剥夺，建立弱视模型。对照组在相同环境下饲养至生后31 d。随后，2组小鼠均于视皮层硬脑膜表面埋置电极。 于生后32 d在麻醉状态下对小鼠的右眼行不同时间频率（2.50、1.25、1.00、0.75、0.50和0.25 Hz）的图形视觉刺激，记 录PVEP，比较2组在不同时间频率的视觉刺激下PVEP的P100波幅值的差异。结果 对照组小鼠对所有6种时间 频率的PVEP P100波反应幅值差异无统计学意义（F=2.214，P＞0.05）；MD组小鼠对6种时间频率的PVEP P100波反 应幅值差异有统计学意义（F=6.588，P＜0.01），其时间频率调制曲线表现为低通特性。与对照组相比，高时间频率 （2.50和1.25 Hz）视觉刺激条件下，MD组P100波幅值显著降低（t分别为2.362和2.425，P＜0.05）。在中低时间频率 （1.00、0.75、0.50和0.25 Hz）刺激条件下，与对照组相比，MD组的P100波反应幅值差异无统计学意义（均P＞0.05）。 结论 MD小鼠对高时间频率视觉刺激的PVEP反应降低，而中低时间频率下的PVEP反应未受到明显影响。     

Serum levels of anti‐Fcγ receptor IIB/C antibodies are increased in patients with systemic sclerosis

Systemic sclerosis (SSc) is a systemic autoimmune disorder that results in fibrosis of the skin and multiple internal organs. Although the precise mechanism is unknown, it appears to result from the overproduction of extracellular matrix proteins and aberrant immune activations. Receptors for the Fc region of immunoglobulin (Ig)G (FcγR) are members of the Ig superfamily that modulate both activation and inhibition of immune responses. FcγRIIB is the sole inhibitory member, which has an intrinsic cytoplasmic immunoreceptor tyrosine‐based inhibitory motif. The present study was undertaken to investigate the circulating concentrations of anti‐FcγRIIB/C antibodies (Ab) in patients with SSc. Serum levels of anti‐FcγRIIB/C Ab were significantly increased in patients with SSc compared to those in controls and in patients with localized scleroderma. Serum levels of anti‐FcγRIIB/C Ab in patients with limited cutaneous SSc were similar to those in patients with diffuse cutaneous SSc. Among SSc patients, serum levels of anti‐FcγRIIB/C Ab were increased in those with nail‐fold bleeding and decreased in those with diffuse pigmentation and calcinosis. These findings support the notion that increased serum anti‐FcγRIIB/C Ab levels are involved in aberrant immune responses in SSc.     

Cardiovascular Efficacy and Safety of PCSK9 Inhibitors: Systematic Review and Meta-analysis Including the ODYSSEY OUTCOMES Trial

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are efficacious lipid-lowering agents, but more precise estimates of their effects on major adverse cardiovascular events (MACE), mortality, and safety are needed. We systematically reviewed and meta-analyzed randomized controlled trials with durations ≥ 6 months comparing MACE, mortality, and safety with PCSK9 inhibitors vs control. We searched CENTRAL, Embase, MedLine and the grey literature to November 7, 2018. From 2048 articles, we included 23 trials (n = 60,723). PCSK9 inhibitors reduced MACE (relative risk, 0.83; 95% confidence interval, 0.78-0.88), but did not clearly reduce mortality (relative risk, 0.93; 95% confidence interval, 0.85-1.02) or increase adverse events. In conclusion, PCSK9 inhibitors reduce nonfatal MACE, are well tolerated, but effects on mortality remain unclear.     

A Convenient Method for Measuring Blood Ascorbate Concentrations in Patients Receiving High-Dose Intravenous Ascorbate

Objective: A simple method of using fingerstick blood glucose (FSBG) monitors to estimate blood ascorbate values after high-dose intravenous (IV) ascorbate infusion is evaluated as a substitution for high-performance liquid chromatography (HPLC) measurement.

Methods: In 33 participants, readings from FSBG monitors were taken before and after IV ascorbate infusions at various time points, with the postinfusion FSBG readings subtracted from the baseline glucose readings. The results of the subtractions (AA_FSBG) were correlated with ascorbate concentrations detected by HPLC (AA_HPLC).

Results: A linear regression was found between ascorbate concentrations detected by the fingerstick method (AA_FSBG) and by HPLC (AA_HPLC). The linear correlations were identical in healthy subjects, diabetic subjects, and cancer patients. Analysis of variance obtained an AA_FSBG/AA_HPLC ratio of 0.90, with a 90% confidence interval of (0.69, 1.20). The corrections of AA_FSBG improved similarity to AA_HPLC but did not significantly differ from the uncorrected values.

Conclusion: The FSBG method can be used as an approximate estimation of high blood ascorbate concentration after IV ascorbate (>50 mg/dL, or 2.8 mM) without correction. However, this measurement is not accurate in detecting lower or baseline blood ascorbate. It is also important to highlight that in regard to glucose monitoring, FSBG readings will be erroneously elevated following IV ascorbate use and insulin should not be administered to patients based on these readings.     

Mitochondrial membrane protein-associated neurodegeneration: a case report and literature review

Mitochondrial membrane protein-associated neurodegeneration (MPAN) is an autosomal recessive disorder caused by mutation in the C19orf12 gene. We report a compound heterozygous c.[32C>T];[205G>A;424A>G] (p.[Thr11Met];[Gly69Arg;Lys142Glu]) Czech patient who manifested with right foot dystonia, impaired handwriting, attention deficit, and signs of iron accumulation on brain MRI. Gradually, he developed dysarthria, spastic-dystonic gait, pedes cavi, and atrophy of leg muscles. Additionally, we report demographic parameters, clinical signs, and allelic frequencies of C19orf12 mutations of all published MPAN cases. We compared the most frequent mutations, p.Thr11Met and p.Gly69ArgfsX10; the latter was associated with younger age at onset and more frequent optic atrophy in homozygotes.     

Consenso Mexicano para el Tratamiento de la Hepatitis C

The aim of the Mexican Consensus on the Treatment of Hepatitis C was to develop clinical practice guidelines applicable to Mexico. The expert opinion of specialists in the following areas was taken into account: gastroenterology, infectious diseases, and hepatology. A search of the medical literature was carried out on the MEDLINE, EMBASE, and CENTRAL databases through keywords related to hepatitis C treatment. The quality of evidence was subsequently evaluated using the GRADE system and the consensus statements were formulated. The statements were then voted upon, using the modified Delphi system, and reviewed and corrected by a panel of 34 voting participants. Finally, the level of agreement was classified for each statement. The present guidelines provide recommendations with an emphasis on the new direct-acting antivirals, to facilitate their use in clinical practice. Each case must be individualized according to the comorbidities involved and patient management must always be multidisciplinary.     

Personalized Blood Flow Restriction Therapy: How,When and Where Can It Accelerate Rehabilitation After Surgery?

Personalized (based on a percentage of a patient's limb occlusion pressure) blood flow restriction is emerging as a potential advancement in orthopaedic surgery. Safe application of the technology requires the use of medical devices capable of customizing the pressures applied to individual patients. In those circumstances, it is a low risk and noninvasive technique. By limiting muscle atrophy and aiding in the recovery of strength and function, it has the potential to significantly reduce the morbidity from limb trauma and surgery, and aid in achieving a substantially earlier return to full activity.