Respiratory Chain Complex-I Defect Mimicking Myasthenia

In a 67-year-old woman with ptosis, double vision, dysphagia, ambiguous Tensilon tests, normal acetylcholine-receptor antibodies, normal thymus, and repeatedly abnormal responses to low-frequency repetitive stimulation, ocular myasthenia was suspected. Pyridostigmin was ineffective, but corticosteroids improved the abnormalities. Despite this therapy, lower-limb weakness developed. Reevaluation disclosed abnormal increase of serum lactate during slight exercise, myogenic electromyography, ragged-red fibers, reduced oxidative enzyme staining and abnormally shaped and structured mitochondria on muscle biopsy, and a respiratory chain complex-I defect on biochemical investigation of the muscle homogenate. Respiratory chain disorder due to complex-I defect with abnormal decremental response to low-frequency repetitive stimulation was diagnosed. It is concluded that respiratory chain disorders due to a complex-I defect may mimic ocular myasthenia clinically, electrophysiologically, and even therapeutically.     

Electrophysiologic characteristics of atrial tachycardia originating from the right pulmonary veins or posterior right atrium: double potentials obtained from the posterior wall of the right atrium can be useful to predict foci of atrial tachycardia in right pulmonary veins or posterior right atrium

INTRODUCTION: The right pulmonary veins (RPVs) and posterior wall of the right atrium (PRA) are anatomically located adjacent to each other. The aim of this study was to demonstrate the electrophysiologic characteristics of atrial tachycardia (AT) originating from the PRA or RPVs. METHODS AND RESULTS: A total of 26 consecutive patients with AT originating from the RPVs or PRA underwent detailed atrial endocardial mapping and successful radiofrequency catheter ablation. Eight foci were found in the PRA and 18 foci in the RPVs. Analysis of P wave configuration showed that lead V1 was the most helpful in distinguishing the AT foci between these two sites. In all cases, double potential (DP) configurations were recorded from several electrodes of a multielectrode catheter placed in the PRA, and the first DP component (FP) was the earliest potential recorded from the right atrium during the tachycardia. The amplitude of the FP was higher than that of the second DP component (SP) for AT foci originating in the PRA, whereas the reverse occurred for those in the RPV. The activation sequence of the FP was from superior to inferior for the AT foci in the superior RPV, whereas the reverse occurred for the AT foci in the inferior RPV. CONCLUSION: P wave configuration in lead V1 is helpful in distinguishing AT foci between those originating in the PRA and RPVs. The DPs obtained from the PRA can be useful in predicting whether AT foci originate from the PRA or RPVs.     

Double outlet right ventricle assessed with Magnetic Resonance Imaging

In this article the value of magnetic resonance (MR) imaging for the evaluation of double outlet right ventricle (DORV) is reviewed from the literature and illustrated with several cases. MR imaging can be used for the determination of cardiac anatomy at initial diagnosis and may provide functional information during the follow-up of patients after surgical correction.     

Y-configuration double-stent-retriever thrombectomy for refractory thrombus in middle cerebral artery bifurcation: A case report

Rationale:Stent retriever mechanical thrombectomy is a recommended treatment for acute ischemic stroke. However, refractory thrombus in artery bifurcation can reduce the rate of successful revascularization.Patient concerns:A 72-year-old male, owing to the acute onset of almost complete right-sided hemiplegia and global aphasia, received bridging therapy. National Institutes of Health Stroke Scale score was 16 at the time of admission.Diagnoses:Cerebral digital subtraction angiography revealed occlusion of the M1 segment of the left MCA.Interventions:Thrombectomy with 3 passes of the Solitaire FR device (Medtronic, Minneapolis, MN) was unsuccessful. Two stent retrievers were inserted in parallel by one microcatheter access point to each M2 branch, and then both stents were gradually retrieved out of the catheter while continuous suction was maintained.Outcomes:After thrombectomy, subsequent follow-up angiograms showed mTICI 3 reperfusion of MCA. The patient has mRS 2 at discharge and the 3-month mRS score after stroke is 1 score.Lessons:The presented Y-configuration double-stent-retriever thrombectomy technique constitutes a safe and effective rescue treatment method for refractory thrombus in MCA bifurcation.     

Comparative study of the effectiveness of slow-release morphine and methadone for opioid maintenance therapy

Aims Slow‐release morphine may represent a much‐needed new pharmacological treatment for opioid dependence. Design In a 14‐week randomized, double‐blind, double‐dummy, cross‐over study oral slow‐release morphine was compared with methadone as a treatment for opioid dependency. During two study periods, each consisting of a 1‐week titration and a 6‐week fixed‐dose treatment phase, medication was administered daily under supervised conditions. Setting The study was carried out at the Addiction Clinic, Department of Psychiatry, Medical University Vienna. Participants Sixty‐four subjects (56 males, eight females) with opioid dependence participated in the trial. Measurements Efficacy was evaluated on the basis of retention, use of illicit substances based on urinalysis, extent of drug cravings, withdrawal symptoms and general wellbeing. Safety was assessed on the basis of adverse events and clinical and physical examination. Demographic and baseline characteristics were assessed using the European Addiction Severity Index. Findings Fifty‐five patients (86%) completed the study, with a mean methadone dose of 85 mg and a mean slow‐release morphine dose of 680 mg. No significant differences in retention or use of illicit substances (opioids, benzodiazepines, cocaine) were observed, irrespective of treatment group or medication. However, patients receiving slow‐release morphine had significantly lower depression (P < 0.001) and anxiety scores (P = 0.008) and fewer physical complaints (P < 0.001). Conclusions Oral slow‐release morphine is as effective as methadone in the treatment of opioid dependency, with comparable safety and tolerability and a greater benefit on patient wellbeing. Greater pharmaceutical diversity represents a modern development in mainstream medicine. Slow‐release morphine might represent a future treatment option that will improve long‐term outcomes for this target group.     

Validation of 64Cu-ATSM damaging DNA via high-LET Auger electron emission

Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a ⁶⁴Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of ⁶⁴Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from ⁶⁴Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair–deficient xrs5 cells were exposed to ⁶⁴Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D₁₀ values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that ⁶⁴Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from ⁶⁴Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after ⁶⁴Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that ⁶⁴Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of ⁶⁴Cu-ATSM as a cancer treatment modality for hypoxic tumors.     

妊娠期肾绞痛的诊疗分析

目的 提高妊娠期肾绞痛的诊断与治疗水平。方法 结合国内外文献,对48例首诊为妊娠期肾绞痛患者的临床资料进行回顾性分析。结果 B超发现肾积水伴输尿管结石21例,其中1例双侧输尿管结石;B超发现肾积水但未发现输尿管结石27例,其中1例首诊误诊为妊娠期肾绞痛,妊娠晚期剖宫产证实为右卵巢畸胎瘤不完全蒂扭转并卵巢部分坏死行卵巢部分切除术。35例行保守治疗有效;1例肾积水进展者、1例双输尿管结石伴双肾积水者、1例肾积脓者及9例顽固性肾绞痛者行Double J(D-J)管置入术;1例重度肾积水者行经皮肾造瘘(Percutaneous Nephrostomy, PCN)术。47例安全顺利分娩或剖宫产,1例早产。结论 妊娠期肾绞痛的诊断具有挑战性,须严格排除其他急腹症。保守治疗对大部分患者有效,但需随访肾积水进展;保守治疗无效时,D-J管置入术是一种安全、简单、有效的治疗方法。     

Zn/Al层状双氢氧化物-聚氯乙烯纳米复合物的制备与性能

用共沉淀法制备油酸钾改性的Zn2+、Al3+层状双氢氧化物（Zn/Al-LDH）,以环己酮为溶剂,用溶液插层法制备了Zn/Al层状双氢氧化物-聚氯乙烯(PVC)纳米复合物。采用傅里叶红外（FT-IR）、X-射线衍射（XRD）、透射电镜(TEM)对复合材料的结构及形貌进行了表征,并用热分析仪、万能试验机和紫外分光光度计研究了复合物的热稳定性能、拉伸性能和紫外吸收性能。结果表明：Zn/Al-LDH纳米片层无序分散在PVC基体中;Zn/Al-LDH对PVC低温时的骨干脱氯化氢有促进作用;与PVC膜相比,复合膜的分解温度降低,高温碳化温度升高,复合膜的拉伸强度及断裂伸长率得到提高,在300~380 nm具有一定的紫外吸收性能。     

Clonally related IgA- and IgE-secreting plasma cells in a myeloma patient

OBJECTIVES: The purpose of this work was to study the clonal relationship between the cells that secrete monoclonal proteins in an IgA/ IgE double multiple myeloma patient. Double monoclonal gammopathy is a rare condition in which two types of monoclonal proteins can be found in the serum and/or urine of patients with multiple myeloma or gammopathy of undetermined significance. The study of the relationship between the cells expressing the different monoclonal proteins may provide insight in the pathogenesis of these disorders. METHODS: The clonal relationship of the two tumoral plasma cell populations was examined by immunophenotyping and sequence analysis of the variable regions of the immunoglobulin heavy chain genes. Both immunoglobulin sequences were isolated from the bone marrow using a polymerase chain reaction (PCR)-based cloning strategy. Rare isotype-switch variants were detected by a myeloma-specific PCR in combination with different isotype-specific primers. An in vitro culture system, based on the activation of the CD40 molecule on the B cell, was used in order to isolate and expand myeloma-related B cells from peripheral blood that could possibly be regarded as myeloma precursor cells. RESULTS: The variable parts of the immunoglobulin heavy chains linked to either Calpha or Cepsilon were exactly the same, including the same somatic mutations. From the in vitro CD40 cultures B cells could be isolated that either expressed IgA or IgE with exactly the same variable immunoglobulin part as the myeloma clone. No pre-switched IgM myeloma-related B cells could be found. CONCLUSION: Both cell populations in this IgA/IgE myeloma patient shared a common clonal origin. No evidence for a pre-switched IgM precursor myeloma cell was found in this patient.