Observer-blinded comparison of two nonopioid analgesics for postoperative pain in piglets

Piglets are popular for studies of respiratory and cardiovascular function, but opioid analgesics are contraindicated in these studies because of central nervous system depression. We evaluated two nonopioid analgesics for postoperative pain relief following implantation of a central arterial catheter via an inguinal incision. Animals were randomly assigned to paracetamol-treated (n=8, rectal suppositories, 100 mg/kg) meloxicam-treated (n=8, 1 mg/kg meloxicam via the catheter) or untreated control group (n=8, placebo suppositories and normal saline). Additional controls received paracetamol or meloxicam, without pain (n=6 for both groups). Behavioral and physiological assessments, and blood sampling were undertaken at nine timed intervals until 24 h after surgery. Multifactorial numerical rating scale (NRS), behavioral and physiological pain scores (PPS) decreased over time for all groups (P<.001). On NRS and behavioral criteria, meloxicam was significantly better than paracetamol (P<.001), and both were better than control (p<.001 for each). Physiological parameters discriminated between the control and analgesia-treated groups, but not between paracetamol and meloxicam. Preliminary pharmacokinetics, determined by isocratic high-performance liquid chromatography (HPLC), revealed no difference in the half-life of paracetamol (2.5+/-0.3 h) vs. meloxicam (3.4+/-0.4 h). Paracetamol and meloxicam provided effective postoperative analgesia in piglets, with meloxicam superior to paracetamol on behavioral criteria.     

Dental amalgam and human health

The use of dental amalgam as a restorative material has long been a contentious issue because of its elemental mercury component. While microleakage of mercury from amalgam has been conclusively confirmed over the past 30 years intensive research has failed to identify deleterious health outcomes. Mercury, as with other metals entering the body tissues, appears to be tolerated at low levels. Nevertheless, a contrary opinion is held by some professional and lay groups who advocate a zero tolerance for inhaled or ingested elemental mercury. They identify dental amalgam as an aetiological factor for neurological conditions such as chronic fatigue syndrome, multiple sclerosis and Alzheimer's disease resulting from chronic mercury poisoning. Epidemiological and clinical evidence of widespread chronic mercury toxicity associated with a body burden of amalgam has consistently failed to be established even in populations with a high prevalence of dental amalgam restorations. On current evidence, international consensus heavily supports the statement that amalgam does not constitute a health risk to patients. However, exposure to volatile free mercury in dental clinics should be controlled to eliminate occupational risk. This paper provides a general review of the current situation and issues. It offers a consensus viewpoint for practitioners and lay people in reaching an informed decision on dental amalgam restorations.     

The vitelliform macular dystrophy protein defines a new family of chloride channels

Vitelliform macular dystrophy (VMD/Best disease; MIM*153700) is an early-onset autosomal dominant disorder in which accumulation of lipofuscin-like material within and beneath the retinal pigment epithelium is associated with a progressive loss of central vision. Bestrophin, the protein product of the VMD gene, has four predicted transmembrane domains. There are multiple bestrophin homologues in the human, Drosophila, and Caenorhabditis elegans genomes, but no function has previously been ascribed to these proteins, and they show no detectable homology to other proteins of known function. Using heterologous expression, we show here that human, Drosophila, and C. elegans bestrophins form oligomeric chloride channels, and that human bestrophin is sensitive to intracellular calcium. Each of 15 missense mutations asscociated with VMD greatly reduces or abolishes the membrane current. Four of these mutant bestrophins were coexpressed with the wild type and each dominantly inhibited the wild-type membrane current, consistent with the dominant nature of the disease. These experiments establish the existence of a new chloride channel family and VMD as a channelopathy.     

Adult interhemispheric subdural haematoma: A simple option for an uncommon problem

Two cases of interhemispheric subdural haematoma are presented. None of the patients had any neurological deficit on admission. They developed progressive neurological deficits within a day or two. Surgical treatment was by a large convexity craniectomy and a wide opening of the dura. The dura was left open in one case and primary duroplasty was done in the other. No deliberate attempt was made to remove the interhemispheric clot. Both patients made a quick and complete recovery by this simple procedure. Cranioplasty was carried out subsequently. Chinese Abstract

Figure Chinese Abstract Open in figure viewer PowerPoint

Volume 6 , Issue 3 August 2002

Pages 87-90     

眼眶硬化性骨髓外造血细胞瘤

骨髓外造血细胞瘤可发生于包括骨髓纤维化、慢性骨髓性门血病和非常少见的红细胞增多症等骨髓增殖紊乱时。当纤维巨细胞增值伴有坚硬肿块形成时，该区域被称为硬化性骨髓外造血细胞瘤（SEMHTs），据我们所知．我们描述的是第一例发生于双侧眼眶SEMHTs的多发性骨髓纤维变中性。     

CT与磁共振成像在儿童人工耳蜗植入术前研究

目的　评价CT与磁共振成像 (magneticresonanceimaging ,MRI)在儿童人工耳蜗植入术前的诊断作用 ,以及对手术选择的影响。方法　 71例 ( 142耳 )双耳重度耳聋、拟行人工耳蜗植入的患儿进行术前CT与MRI检查。结果　CT与MRI均发现 ,12例 ( 2 2耳 )患者有前庭水管扩大 ( 15 5 % ) ;14例 ( 2 5耳 )患儿有Mondini畸形 ( 17 6% ) ;3例 ( 5耳 )患儿有内耳道扩大 ( 3 5 % ) ;2例 ( 4耳 )患者有可疑内耳道底骨质缺损 ( 2 8% )。MRI发现有 5例 ( 5耳 )患者单侧耳蜗纤维化 ( 3 5 % ) ,而CT未见异常。1例 ( 2耳 )患儿的CT显示面神经裸露 ( 1 4% ) ,MRI正常。结论　人工耳蜗植入术前应该进行CT与MRI检查。对于发现前庭水管综合征、Mondini畸形、内耳道扩张及内耳道底骨质缺损有重要意义。这二种影像学检查结果可以相互补充诊断耳蜗纤维化与面神经裸露。对手术适应证的选择以及保证手术正常进行有重要意义     

Combined staged anterior and posterior correction and fusion of the spine in scoliosis following poliomyelitis.

The problems with severe forms of scoliosis following poliomyelitis include the associated muscle imbalance, soft tissue contractures and pelvic obliquity. Such deformities militate against optimal correction and maintenance of that correction and their treatment is often marred by pseudarthroses. Seventeen patients with an average curve of 93 degrees have been treated and followed for up to 38 months. Preliminary traction was used in 8 patients, then a staged anterior and posterior correction and fusion was done, using Dwyer's instrumentation of the major curve in all and a Harrington rod to supplement the posterior fusion in eleven patients. With this technique the major curve was corrected by 80 per cent with an average 2 per cent loss over 18 months. No pseudarthroses were seen when the Harrington rod was used. Great care must be taken if halo-pelvic traction is to be used for patients with pelvic obliquity, for preliminary correction halo-femoral traction will often be adequate. In the more severe forms of paralytic scoliosis a combined staged anterior and posterior correction and fusion should be considered if the aim is maximal correction of the scoliosis and avoidance of pseudarthroses.