Review of gated SPECT imaging in women with suspected coronary heart disease

Conclusions  MPI has weathered many challenges over the decades, and, with advances such as gated SPECT acquisition, technetium radiotracers, and attenuation correction software, it has overcome many of its shortcomings to remain a cornerstone of noninvasive cardiac imaging, which has high diagnostic accuracy in women.¹⁴     

Evaluation of the integrated 3-hour plasma cortisol concentration as a test for Cushing's syndrome

Twenty-four hour urinary free cortisol and mean and integrated 13h00-16h00 plasma cortisol levels were measured in 9 patients with proven Cushing's syndrome (5 with Cushing's disease, 2 with ectopic adrenocorticotrophic hormone production due to bronchial carcinoma and 2 with adrenal adenomas) and in 21 patients without Cushing's syndrome. The 24-hour urinary free cortisol levels and mean and integrated 13h00-16h00 plasma cortisol estimations clearly distinguished patients with Cushing's syndrome from those without. However, adequate suppression on dexamethasone suppression tests (false negatives) were obtained in 3 of the 9 patients with Cushing's syndrome. Since the integrated 13h00-16h00 plasma cortisol estimation is cheaper and simpler than the mean 13h00-16h00 plasma cortisol estimation, we recommend it as an adjunct in the diagnosis of Cushing's syndrome.     

Noma (cancrum oris): case report in a 4-year-old HIV-positive South African child.

Cancrum oris (noma) is a gangrenous infection that develops in the mouth and spreads rapidly to other parts of the face. The disease occurs mostly in conditions of poverty, poor hygiene and malnutrition. In sub-Saharan Africa the frequency in several countries is estimated to be 1-7 cases per 1,000 population, and as many as 12 cases per 1,000 in the most affected communities. About 90% of these children die without receiving any care, yet the disease can, and should, be prevented. With increasing numbers of children who are malnourished and who have compromised immune systems (compounded by the HIV pandemic) the prevalence of conditions such as noma is likely to increase. Among the earliest features of noma are excessive salivation, marked fetor oris, facial oedema and a greyish-black discolouration of the skin in the affected area. This devastating gangrenous lesion may involve the cheek, the chin, the infra-orbital margin, palate, nose, antrum and virtually any part of the face. This report describes a 4-year-old HIV-positive African girl, who was abandoned, discharged from the Plastics Unit and now lives in a child care sanctuary. Little is known about her history prior to her arrival at the home a few weeks previously. The clinical examination revealed a delay in growth and physical development equivalent to that of a 2-year-old child. The left cheek had a perforating ulcer in a healing phase. The perforation, about 1 cm in diameter, was surrounded by oedematous tissues showing a mild to moderate erythema. The peripheral oedema extended to the lower palpebral, the upper labial, left labial commissural, mandibular and pre-parotid regions. Submental, submandibular and cervical lymph nodes were mildly painful upon palpation. The child was not pyretic. The intra-oral examination revealed the features of acute necrotising gingivitis (ANG). ANG was generalised and showed classic interdental crater-like ulcers covered with whitish debris. Halitosis was pronounced. Examination of the second quadrant revealed a large ulcer extending from the distal aspect of the deciduous canine to the distal aspect of the second deciduous molar. The adjacent palatal mucosa was severely oedematous. The alveolar bone supporting the first and the second molars was completely exposed to the fundus of the vestibulum. It was not possible to obtain intraoral photographs or radiographs. Chlorhexidine gluconate (0.2% solution) and metronidazole tablets, 200 mg twice daily for 15 days were prescribed. The child was seen every alternate day for 10 days and her condition improved rapidly. Halitosis had subsided. She was then referred to the Johannesburg Hospital for further treatment under general anaesthesia. The proposed treatment plan was as follows: removal of dental accretions and polishing of all teeth, extraction of the left maxillary teeth supported by non-vital bone, resection of the necrotic bone in the left maxilla and reconstructive surgery in the left cheek.     

Inhibition of ligand binding to g protein-coupled receptors by arachidonic acid

Arachidonic acid (AA), released in response to muscarinic acetylcholine receptor (mAChR) stimulation, previously has been reported to function as a reversible feedback inhibitor of the mAChR. To determine if the effects of AA on binding to the mAChR are subtype specific and whether AA inhibits ligand binding to other G protein-coupled receptors (GPCRs), the effects of AA on ligand binding to the mAChR subtypes (M₁, M₂, M₃, M₄, and M₅) and to the μ-opioid receptor, β₂-adrenergic receptor (β₂-AR), 5-hydroxytryptamine receptor (5-HTR), and nicotinic receptors were examined. AA was found to inhibit ligand binding to all mAChR subtypes, to the β₂-AR, the 5-HTR, and to the μ-opioid receptor. However, AA does not inhibit ligand binding to the nicotinic receptor, even at high concentrations of AA. Thus, AA inhibits several types of GPCRs, with 50% inhibition occurring at 3–25 μM, whereas the nicotinic receptor, a non-GPCR, remains unaffected. Further research is needed to determine the mechanism by which AA inhibits GPCR function.     

Urinary tract infection withCorynebacterium urealyticum in South Africa

Corynebacterium urealyticum has been well documented as a urinary pathogen in Europe. The purpose of this study was to investigate the incidence and clinical relevance ofCorynebacterium urealyticum as a urinary pathogen in a predominantly Third World population (South Africa) and to attempt to increase the isolation rate by culturing urine specimens on a selective medium. Two methods were used to isolateCorynebacterium urealyticum from urine specimens. Blood agar plates from routine urine cultures of 7,912 urine specimens were incubated for 48 hours and 1,281 specimens were cultured on a selective medium as well as on routine media. The antimicrobial susceptibility of all isolates ofCorynebacterium urealyticum was tested. The yield ofCorynebacterium urealyticum on blood agar was three isolates in three patients (0.038% of 7,912), all of whom had pyuria, alkaline urine and risk factors forCorynebacterium urealyticum infection. Use of selective media increased the yield ofCorynebacterium urealyticum to 15 of 1,281 specimens (1.17%), however 73% of these urine samples yielded other pathogens and none had an alkaline pH which could not be attributed to the presence of another urealytic pathogen. All isolates were susceptible to vancomycin and 92.6% susceptible to norfloxacin. The pathogenic potential ofCorynebacterium urealyticum was confirmed in South African patients, but the incidence of infection was low. The use of a selective medium is therefore not cost-effective in all cases but could be used selectively on the basis of typical urine findings and patient criteria.     

Linkage of chromosome 13q32 to schizophrenia in a large veterans affairs cooperative study sample

Several prior reports have suggested that chromosomal region 13q32 may harbor a schizophrenia susceptibility gene. In an attempt to replicate this finding, we assessed linkage between chromosome 13 markers and schizophrenia in 166 families, each with two or more affected members. The families, assembled from multiple centers by the Department of Veterans Affairs Cooperative Studies Program, included 392 sampled affected subjects and 216 affected sib pairs. By DSM-III-R criteria, 360 subjects (91.8%) had a diagnosis of schizophrenia and 32 (8.2%) were classified as schizoaffective disorder, depressed. The families had mixed ethnic backgrounds. The majority were northern European-American families (n = 62, 37%), but a substantial proportion were African-American kindreds (n = 60, 36%). Chromosome 13 markers, spaced at intervals of approximately 10 cM over the entire chromosome and 2-5 cM for the 13q32 region were genotyped and the data analyzed using semi-parametric affected only linkage analysis. For the combined sample (with race broadly defined and schizophrenia narrowly defined) the maximum LOD score was 1.43 (Z-score of 2.57; P = 0.01) at 79.0 cM between markers D13S1241 (76.3 cM) and D13S159 (79.5 cM). Both ethnic groups showed a peak in this region. The peak is within 3 cM of the peak reported by Brzustowicz et al. [1999: Am J Hum Genet 65:1096-1103].