Infrared spectroscopy: shedding light on synovitis in patients with rheumatoid arthritis

OBJECTIVES: It is difficult to determine the extent of synovial involvement early in the course of rheumatoid arthritis. A spectroscopic technique was used to characterize the synovium of the small finger joints in both early and late rheumatoid arthritis. This synovium was also compared against normal joints. METHODS: Near-infrared spectroscopy assesses the absorption of near-infrared light by specific joints, giving a characteristic "fingerprint" of the properties of the underlying tissues. Triple measurements by infrared spectroscopy were taken at the bilateral second and third metacarpophalangeal joints. Multivariate analysis was applied. RESULTS: Analysis was able to demonstrate relationships between the specific sources of spectral variation and joint tenderness or swelling as well as radiographic damage. Further use of multivariate analysis allowed recognition of the spectral patterns seen in early disease vs late rheumatoid arthritis and correct classification of over 74% of the joints. CONCLUSIONS: The spectral regions where differences occurred were in the absorption bands related to tissue oxygenation status, allowing the provocative implication that this technique could be detecting ischaemic changes within the joint. Near-infrared spectroscopy may thus be able to provide us with some information about the biochemical changes associated with synovitis.     

Training teachers--changing practice?

A three-day course was designed to improve the skills of those who provide clinical training to medical students. This long-term follow up of past participants shows a sustained improvement to their skills, especially in terms of involving students in their own learning, and giving them positive feedback.     

The doctor as God's mechanic? Beliefs in the Southeastern United States

Spiritual practice and beliefs related to healing are described using data from a telephone survey. Questions in the survey address the practice of prayer and spiritual beliefs related to healing. Questions explore belief in miracles, that God acts through religious healers, the importance of God's will in healing, and that God acts through physicians. Questions also ask whether people discuss spiritual concerns with their physician and whether they would want to if seriously ill. We create a composite index to compare religious faith in healing across race, gender, education, income denomination, and health status. Logistic regression predicts types of patients who believe God acts through physicians and those inclined to discuss spiritual concerns when ill. The most important findings are that: 80% of respondents believe God acts through physicians to cure illness, 40% believe God's will is the most important factor in recovery, and spiritual faith in healing is stronger among women. African-Americans, Evangelical Protestants, the poorer, sicker, and less educated. Those who believe that God acts through physicians are more likely to be African-American than White (OR = 1.9) and 55 or older (OR = 3.5). Those who discuss spiritual concerns with a physician are more likely to be female (OR = 1.9) and in poor health (OR = 2.1). Although 69% say they would want to speak to someone about spiritual concerns if seriously ill, only 3% would choose to speak to a physician. We conclude that religious faith in healing is prevalent and strong in the southern United States and that most people believe that God acts through doctors. Knowledge of the phenomena and variation across the population can guide inquiry into the spiritual concerns of patients.     

Implications of lymphatic drainage to unusual sentinel lymph node sites in patients with primary cutaneous melanoma

BACKGROUND: Sentinel lymphadenectomy reliably identifies the first site(s) of regional lymphatic drainage and, therefore, the most likely lymph nodes to contain occult metastasis in patients with primary cutaneous melanoma. Although in most patients lymphatic drainage from the primary melanoma first reaches a standard lymph node basin, a sentinel lymph node (SLN) may be identified in an unusual location. The objective of this study was to determine the frequency and significance of unusual sentinel lymph node drainage patterns in a large cohort of patients with primary melanoma. METHODS: The records of 1145 consecutive primary melanoma patients who underwent SLN biopsy were reviewed. Preoperative lymphoscintigraphy was performed in all patients with truncal melanoma and in many patients with distal extremity lesions. Unusual lymph node sites were defined as epitrochlear, popliteal, or ectopic/interval (in-transit or any other nonstandard lymph node-bearing area). RESULTS: At least one SLN was harvested in 1117 patients (98%). SLN biopsy of an unusual lymph node site was attempted in 59 patients (5%). Successful intraoperative localization and biopsy was performed in 54 (92%) of 59 patients for a total of 56 unusual sites. Of these, 7 (13%) were popliteal, 8 (14%) were epitrochlear, and 41 (73%) were ectopic/interval. Preoperative lymphoscintigraphy was performed in 41 of these 54 patients and correctly identified unusual SLN locations in 12 (29%); the majority of unusual SLNs were identified only with the assistance of the intraoperative gamma probe. In four patients (7%), the unusual lymph node site was the only site from which SLNs were harvested. In the remaining 50 patients (93%), biopsies were performed on SLNs from both unusual sites and from a standard lymph node basin. Among the 54 patients who underwent a SLN biopsy of an unusual nodal site, 7 (13%) had lymph node metastases in that location. In four of the seven patients, the only positive SLN was from the unusual site. CONCLUSIONS: Sentinel lymphatic drainage patterns include lymph node-bearing areas that may be outside established standard lymph node basins and may represent the only site of regional lymph node metastases. Although preoperative lymphoscintigraphy may assist in the identification of unusual SLN drainage patterns, intraoperative use of the gamma probe is recommended to identify accurately and completely all sites of regional lymph node drainage.     

Clinical evaluation of biomarkers in Gaucher disease

Novel or candidate biomarkers require thorough evaluation to establish their utility in a clinical setting. This paper describes an evaluation of several established enzyme markers of Gaucher disease and a newly-described chemokine, pulmonary and activation-regulated chemokine (PARC). The ability of the biomarkers to rank patients with Gaucher disease in order of disease severity and organ bulk, and to reflect changes in key clinical parameters in response to enzyme replacement therapy were evaluated. PARC concentrations were found to be reliably correlated with visceral disease and with key clinical responses to enzyme replacement in an unbiased manner. Unlike chitotriosidase and serum angiotensin-converting enzyme activity, genetic variation in serum PARC did not appear to influence its utility as a biomarker.
Conclusion: For each new candidate biomarker of lysosomal storage diseases, a similar clinical evaluation will be required, though the approach will need to be modified according to the clinical features and natural history of each disorder.     

Polymorphisms in the DNA repair genes XPC, XPD, and XPG and risk of cutaneous melanoma: a case-control analysis.

Sunlight causes DNA damage, including bulky lesions that are removed effectively by the nucleotide-excision repair (NER) pathway. There are at least eight core NER proteins participating in the pathway, and genetic variations in their genes may alter NER functions. We hypothesized that some NER variants are associated with risk of cutaneous melanoma. In a hospital-based case-control study of 602 non-Hispanic White patients with cutaneous melanoma and 603 age- and sex-matched cancer-free controls, we genotyped five common non-synonymous single-nucleotide polymorphisms identified to date and assessed their associations with risk of cutaneous melanoma. We found that a significantly increased risk of cutaneous melanoma was associated with XPD 751Lys/Gln [adjusted odds ratio (OR), 1.55 and 95% confidence interval (95% CI), 1.12-2.16] and XPD 751Gln/Gln (OR, 1.66; 95% CI, 1.03-2.68) genotypes compared with the XPD 751Lys/Lys genotype as well as XPD312Asp/Asn (OR, 1.54; 95% CI, 1.11-2.12) and XPD312Asn/Asn (OR, 1.75; 95% CI, 1.05-2.90) genotypes compared with the XPD 312Asp/Asp genotype. This increased risk was not observed in the other three XPC and XPG single-nucleotide polymorphisms. Moreover, the number of the observed XPD at-risk genotypes (i.e., 312Asn/Asn+Asn/Asp and 751Gln/Gln+Lys/Gln) was associated with cutaneous melanoma risk in a dose-response manner (OR, 1.47; 95% CI, 0.97-2.23 for one at-risk genotype; OR, 1.83; 95% CI, 1.29-2.61 for two at-risk genotypes; P(trend) < 0.001). However, we found no evidence of any interaction between XPD genotypes with XPC and XPG genotypes or the known risk factors. We concluded that genetic variants of the XPD gene might serve as biomarkers for susceptibility to cutaneous melanoma.     

Role for Lymphatic Mapping and Sentinel Lymph Node Biopsy in Patients With Thick (≥4 mm) Primary Melanoma

Background: Historically, patients with thick (4 mm) primary melanoma have not been considered candidates for elective lymph node dissection, because their risk for occult distant disease is significant. Sentinel lymph node (SLN) biopsy offers an alternative approach to assess disease in the regional nodal basin, but no studies have specifically addressed the role for this technique in patients with thick melanoma. Although adjuvant therapy benefits patients who develop nodal metastases, data that supports its routine use in all patients with thick melanoma is both limited and controversial. This study was performed to determine whether pathological status of the SLN is an important risk factor in this heterogeneous group and, thus, provides a rationale for SLN biopsy.Methods: The records of 131 patients with primary cutaneous melanoma whose primary tumors were at least 4 mm thick and who underwent lymphatic mapping and SLN biopsy were reviewed. Several known prognostic factors, i.e., tumor thickness, ulceration, Clark level, location, sex, as well as SLN pathological status were analyzed with respect to disease-free and overall survival.Results: Lymphatic mapping and SLN biopsy was successful in 126 (96%) of 131 patients who underwent the procedure. In 49 patients (39%), the SLN biopsy was positive by conventional histology, although it was negative in 77 patients (61%). The median follow-up was 3 years. Although presence of ulceration and SLN status were independent prognostic factors with respect to disease-free and overall survival, SLN status was the most powerful predictor of overall survival by univariate and multivariate analyses.Conclusions: Lymphatic mapping and SLN biopsy is a highly accurate method of staging lymph node basins at risk for regional metastases in patients with thick melanoma and identifies those patients who may benefit from earlier lymphadenectomy as well as patients with a more favorable prognosis. Pathological status of the SLN in these patients with clinically negative nodes is the most important prognostic factor for survival and is essential to establish stratification criteria for future adjuvant trials in this high-risk group.Presented at the 52nd Annual Meeting of the Society of Surgical Oncology, Orlando, Florida, March 4–7, 1999.     

Role of polymorphisms in the interleukin-10 gene in determining disease susceptibility and phenotype in inflamatory bowel disease

Interleukin-10 (IL-10) has a key role in regulating mucosal inflammation. The role of functional polymorphisms at positions –627 and –1117 in the IL-10 gene as candidate susceptibility loci in inflammatory bowel disease and their importance in determining disease extent were evaluated in 159 patients with ulcerative colitis (83 left-sided; 76 extensive), 90 patients with Crohn's disease (22 small bowel; 29 large bowel; 39 both), and 227 controls. Genotyping was performed either by PCR-RFLP assays (–627 site) or SSCP analysis (–1117 site). An excess of –627A allele was observed in patients with left-sided colitis (52%) compared with controls (33%; P = 0.004) suggesting that IL-10 may influence the extent of the disease. These results were not replicated in a newly recruited group (N = 100) of patients with UC. We conclude that polymorphisms at –627 and –1117 sites in the IL-10 gene do not contribute to the susceptibility to IBD or determining the extent of the disease in our population.     

Hirschprung's disease

Current evidence on the pathogenesis of Hirschprung's disease, then, favours the 'abnormal microenvironment' hypothesis wherein the developing and migrating normal neural crest cells confront a segmentally abnormal and hostile microenvironment in the colon. This hypothesis would account both for the congenital absence of ganglion cells in the wall of colon and also for the range of enteric neuronal abnormalities encountered including neuronal dysplasia, hypoganglionosis, and zonal aganglionosis. The abnormal constitution of the mesenchymal and basement membrane extracellular matrix in the affected segment of colon is presumably genetically determined and further understanding of the pathogenesis of this disorder will emerge as molecular geneticists characterise the specific genes and gene products associated with Hirschprung's disease. Advances in this field should permit gene probes to be developed to facilitate prenatal and postnatal diagnosis.