417 Vibrational Spectroscopy: A Rapid Tool for Soft Tissue Sarcoma Assessment

Aim

Soft tissue sarcomas (STS) are a comparatively unusual cluster of tumours; they arise from mesenchymal tissues. Surgery remains the primary and the only potentially curative treatment for most STS subtypes.

Existing intraoperative margin assessment techniques are inadequate and the current gold standard for resection margin assessment of STS is post-operative histopathology, but this takes weeks to finalize. Consequently, an augmented surgical technique established by real-time non-destructive recognition of clear margins is essential to diminish the risk of local relapse, decrease the resection area, and enhance the effectiveness of surgical resection of STS.

Vibrational spectroscopy (VS) is a non-destructive evaluation of the atomic oscillation within a molecule. Every molecule has a unique set of vibrational modes called molecular fingerprint. We aim to use Raman spectroscopy to analyse biomolecular spectra of sarcoma and develop a potential tool for intra operative margin assessment

Method

Human sarcoma was tissue obtained from the biobank at QEHB. The samples were identified as Lipoma and Liposarcoma. The samples underwent spectral measurement with the Raman microscope and the tissue samples were then sent for histopathological analysis.

Results

The spectral evaluation clearly demonstrates the biomolecular difference between the two groups and has a potential to become an intraoperative tool.

Conclusions

A positive resection margin is the ultimate prognosticator of local relapse. There is a need for a rapid and reliable tool that can offer surgeons with instant feedback during primary procedure.

Multi-centre Raman spectral mapping of oesophageal cancer tissues: a study to assess system transferability

The potential for Raman spectroscopy to provide early and improved diagnosis on a wide range of tissue and biopsy samples in situ is well documented. The standard histopathology diagnostic methods of reviewing H&E and/or immunohistochemical (IHC) stained tissue sections provides valuable clinical information, but requires both logistics (review, analysis and interpretation by an expert) and costly processing and reagents. Vibrational spectroscopy offers a complimentary diagnostic tool providing specific and multiplexed information relating to molecular structure and composition, but is not yet used to a significant extent in a clinical setting. One of the challenges for clinical implementation is that each Raman spectrometer system will have different characteristics and therefore spectra are not readily compatible between systems. This is essential for clinical implementation where classification models are used to compare measured biochemical or tissue spectra against a library training dataset. In this study, we demonstrate the development and validation of a classification model to discriminate between adenocarcinoma (AC) and non-cancerous intraepithelial metaplasia (IM) oesophageal tissue samples, measured on three different Raman instruments across three different locations. Spectra were corrected using system transfer spectral correction algorithms including wavenumber shift (offset) correction, instrument response correction and baseline removal. The results from this study indicate that the combined correction methods do minimize the instrument and sample quality variations within and between the instrument sites. However, more tissue samples of varying pathology states and greater tissue area coverage (per sample) are needed to properly assess the ability of Raman spectroscopy and system transferability algorithms over multiple instrument sites.

Expanding conceptualizations of harm reduction: results from a qualitative community-based participatory research study with people who inject drugs

Background

The perspectives of people who use drugs are critical in understanding why people choose to reduce harm in relation to drug use, what practices are considered or preferred in conceptualizations of harm reduction, and which environmental factors interfere with or support the use of harm reduction strategies. This study explores how people who inject drugs (PWID) think about harm reduction and considers the critical imperative of equity in health and social services delivery for this community.

Methods

This community-based participatory research study was conducted in a Canadian urban centre. Using a peer-based recruitment and interviewing strategy, semi-structured qualitative interviews were conducted by and with PWID. The Vidaview Life Story Board, an innovative tool where interviewers and participant co-construct a visual “life-scape” using a board, markers, and customized picture magnets, was used to facilitate the interviews. The topics explored included injection drug use and harm reduction histories, facilitators and barriers to using harm reduction strategies, and suggestions for improving services and supports.

Results

Twenty-three interviews with PWID (14 men and 9 women) were analysed, with a median age of 50. Results highlighted an expanded conceptualization of harm reduction from the perspectives of PWID, including motivations for adopting harm reduction strategies and a description of harm reduction practices that went beyond conventional health-focused concerns. The most common personal practices that PWID used included working toward moderation, employing various cognitive strategies, and engaging in community activities. The importance of social or peer support and improving self-efficacy was also evident. Further, there was a call for less rigid eligibility criteria and procedures in health and social services, and the need to more adequately address the stigmatization of drug users.

Conclusions

These findings demonstrated that PWID incorporate many personal harm reduction practices in their daily lives to improve their well-being, and these practices highlight the importance of agency, self-care, and community building. Health and social services are needed to better support these practices because the many socio-structural barriers this community faces often interfere with harm reduction efforts. Finally, “one size does not fit all” when it comes to harm reduction, and more personalized or de-medicalized conceptualizations are recommended.

Malignant metastatic deposits in an immunocompromised patient—could this be tuberculosis?

We report the case of a 50-year-old female renal transplant patient who developed disseminated deposits initially diagnosed as metastatic malignancy of unknown primary. She declined a tissue diagnosis but subsequently developed recurrent sepsis and symptomatic unilateral pleural effusion. Mycobacterium tuberculosis was cultured from pleural fluid. Following introduction of anti-tuberculous medications, her symptoms improved rapidly and the progression of her disseminated deposits stabilized. Tuberculosis is well-known to be associated with immunocompromised patients. It is a curable disease and should remain an important differential diagnosis for transplant patients who develop suspicious malignant metastatic lesions.

Risk factors associated with resistance to HIV testing among transwomen in Brazil

Transwomen are a high-risk population for HIV/AIDS worldwide. However, many transwomen do not test for HIV. This study aimed to identify factors associated with resistance to HIV testing among transwomen in Fortaleza/CE. A cross-sectional study was conducted between August and December 2008 with a sample of 304 transwomen recruited through respondent-driven sampling. Data analysis utilized Respondent-Driven Sampling Analysis Tool and SPSS 11.0. Univariate, bivariate, and multivariate analyses examined risk factors associated with resistance to HIV testing. Less than 18 years of age (OR = 4.221; CI = 2.419-7.364), sexual debut before 10 years of age (OR = 6.760; CI = 2.996-15.256), using illegal drugs during sex (OR = 2.384; CI = 1.310-4.339), experience of discrimination (OR = 3.962; CI = 1.540-10.195) and a belief that the test results were not confidential (OR = 3.763; CI = 2.118-6.688) are independently associated with resistance to testing. Intersectoral and targeted strategies aimed at encouraging the adoption of safer sexual behaviors and testing for HIV among transwomen are required.

Evaluation of a confocal Raman probe for pathological diagnosis during colonoscopy

AIM

Raman spectroscopy of human tissue can provide a unique biochemical 'fingerprint' that alters with disease progression. Light incident on tissue is scattered and may be altered in wavelength, which can be represented as a Raman spectrum. A confocal fibreoptic Raman probe designed to fit down the accessory channel of a colonoscope has been constructed. This in-vitro study evaluated the accuracy of pathological diagnosis in the colon using probe-based Raman spectroscopy.

METHOD

Biopsy samples were collected at colonoscopy, snap frozen and stored at -80 °C. Raman spectra with 10-s and 1-s acquisition periods were measured with the probe tip in contact with the mucosal surface of thawed specimens. Mathematical modelling using principal component analysis followed by linear discriminant analysis was used to correlate Raman spectra with histopathological diagnoses.

RESULTS

Three-hundred and seventy-five Raman spectra were measured from a total of 356 colon biopsies (81 of normal colon mucosa, 79 of hyperplastic polyps, 92 of adenomatous polyps, 64 of adenocarcinoma and 40 of ulcerative colitis) from 177 patients. Spectral classification accuracies comparing pathology pairs ranged from 72.1 to 95.9% for 10-s acquisitions and from 61.5 to 95.1% for 1-s acquisitions. For a three-group model of normal, adenomatous and adenocarcinoma tissue, accuracies were 74.1% for 10-s acquisitions and 63.5% for 1-s acquisitions.

CONCLUSION

The confocal Raman probe system can distinguish between different colorectal pathologies. The probe has potential to establish Raman spectroscopy as a clinical tool for instant diagnosis at colonoscopy.

Signal-to-noise contribution of principal component loads in reconstructed near-infrared Raman tissue spectra

The overall quality of Raman spectra in the near-infrared region, where biological samples are often studied, has benefited from various improvements to optical instrumentation over the past decade. However, obtaining ample spectral quality for analysis is still challenging due to device requirements and short integration times required for (in vivo) clinical applications of Raman spectroscopy. Multivariate analytical methods, such as principal component analysis (PCA) and linear discriminant analysis (LDA), are routinely applied to Raman spectral datasets to develop classification models. Data compression is necessary prior to discriminant analysis to prevent or decrease the degree of over-fitting. The logical threshold for the selection of principal components (PCs) to be used in discriminant analysis is likely to be at a point before the PCs begin to introduce equivalent signal and noise and, hence, include no additional value. Assessment of the signal-to-noise ratio (SNR) at a certain peak or over a specific spectral region will depend on the sample measured. Therefore, the mean SNR over the whole spectral region (SNR(msr)) is determined in the original spectrum as well as for spectra reconstructed from an increasing number of principal components. This paper introduces a method of assessing the influence of signal and noise from individual PC loads and indicates a method of selection of PCs for LDA. To evaluate this method, two data sets with different SNRs were used. The sets were obtained with the same Raman system and the same measurement parameters on bladder tissue collected during white light cystoscopy (set A) and fluorescence-guided cystoscopy (set B). This method shows that the mean SNR over the spectral range in the original Raman spectra of these two data sets is related to the signal and noise contribution of principal component loads. The difference in mean SNR over the spectral range can also be appreciated since fewer principal components can reliably be used in the low SNR data set (set B) compared to the high SNR data set (set A). Despite the fact that no definitive threshold could be found, this method may help to determine the cutoff for the number of principal components used in discriminant analysis. Future analysis of a selection of spectral databases using this technique will allow optimum thresholds to be selected for different applications and spectral data quality levels.

A miniature confocal Raman probe for endoscopic use

Raman spectroscopy is a powerful tool for studying biochemical changes in the human body. We describe a miniature, confocal fibre optic probe intended to fit within the instrument channel of a standard medical endoscope. This probe has been optimized for the study of the carcinogenesis process of oesophageal malignancy. The optical design and fabrication of this probe is described including the anisotropic wet etching technique used to make silicon motherboards and jigs. Example spectra of PTFE reference samples are shown. Spectra with acquisition times as low as 2 s from resected oesophageal tissue are presented showing identifiable biochemical changes from various pathologies.

Intake and milk production of cows fed diets that differed in dietary neutral detergent fiber and neutral detergent fiber digestibility

The objectives of this study were to determine how feeding diets that differed in dietary neutral detergent fiber (NDF) concentration and in vitro NDF digestibility affects dry matter (DM) intake, ruminal fermentation, and milk production in early lactation dairy cows. Twelve rumen-cannulated, multiparous Holstein cows averaging 38 +/- 15 d (+/-standard deviation) in milk, and producing 40 +/- 9 kg of milk daily, were used in a replicated 4 x 4 Latin square design with 28-d periods. Treatment diets were arranged in a 2 x 2 factorial with 28 or 32% dietary NDF (DM basis) and 2 levels of straw NDF digestibility: 1) LD, untreated wheat straw (77% NDF, 41% NDF digestibility) or 2) HD, anhydrous NH(3)-treated wheat straw (76% NDF, 62% NDF digestibility). All 4 diets consisted of wheat straw, alfalfa silage, corn silage, and a concentrate mix of cracked corn grain, corn gluten meal, 48% soybean meal, and vitamins and minerals. Wheat straw comprised 8.5% DM of the 28% NDF diets and 16% DM of the 32% NDF diets. Cows fed 28% NDF and HD diets produced more milk, fat, and protein than those consuming 32% NDF or LD diets. Dry matter intake was greater for cows consuming 28% NDF diets, but intakes of DM and total NDF were not affected by in vitro NDF digestibility. Intake of digestible NDF was greater for cows consuming HD diets. Ruminal fermentation was not affected by feeding diets that differed in NDF digestibility. Ruminal NDF passage rate was slower for cows fed HD than LD. No interactions of dietary NDF concentration and in vitro NDF digestibility were observed for any parameter measured. Regardless of dietary NDF concentration, increased in vitro NDF digestibility improved intake and production in early lactation dairy cows.

Pleomorphic adenoma arising from the tail of the parotid gland - value of preoperative multi planar imaging: a case report

Background

Lesions of the 'tail' of the parotid gland are difficult to assess clinically and provide a diagnostic dilemma on imaging, especially in the axial plane. Pedunculated lesions of the 'tail' of parotid can be mistaken for an extra parotid lesion. Accurate localisation of these lesions on imaging is essential to assist the clinical diagnosis, to prevent inadequate/incomplete excision and complications, especially damage to facial nerve.

Case Report

In this case report, we present a case of a pleomorphic adenoma arising from the 'tail' of the parotid gland, which on imaging, appears to be extra parotid in location. We also review the anatomy of the parotid 'tail' and relevant literature.

Conclusion

Lesions of the parotid 'tail' are a diagnostic challenge to clinicians and Radiologists. Pedunculated lesions arising from the 'tail' of the parotid gland can appear extra parotid in location. Knowledge of parotid gland anatomy and use of multi planar imaging is essential in the accurate localisation of these lesions. This will also prevent inadequate or incomplete excision.

HIV-positive women in northeast Brazil: tubal sterilization, medical recommendation and reproductive rights

Tubal sterilization is the most common contraceptive method used by Brazilian HIV-positive women. This cross sectional study describes the main reasons why HIV-positive women decide to be sterilized and identifies factors associated with choosing sterilization in HIV-positive women in Ceará, northeast Brazil. Data from 229 non-sterilized women, 80 women sterilized before HIV diagnosis and 48 women sterilized after diagnosis were analysed. Of the women sterilized after HIV diagnosis, 96% had the procedure done in the postpartum, during a caesarean section. No desire for more children was the most common appointed reason to be sterilized (39.6%), followed by medical recommendation because of HIV (31.3%). Seventy-nine women (28.5%) had a child after HIV diagnosis. Of those, 46 (58.2%) were sterilized in the postpartum. Factors associated with sterilization for HIV-positive women were: having a child after diagnosis (AOR: 120.9; 95%CI: 27.8-525.4) and having at least three children (AOR: 2.8; 95%CI: 1.1-7.1). It is recommended that non-coercive counselling should be provided so that HIV-positive women can make informed decisions on their reproductive options.

Nitrogen isotopes as indicators of NO(x) source contributions to atmospheric nitrate deposition across the midwestern and northeastern United States

Global inputs of NO(x) are dominated by fossil fuel combustion from both stationary and vehicular sources and far exceed natural NO(x) sources. However, elucidating NO(x) sources to any given location remains a difficult challenge, despite the need for this information to develop sound regulatory and mitigation strategies. We present results from a regional-scale study of nitrogen isotopes (delta15N) in wet nitrate deposition across 33 sites in the midwestern and northeastern U.S. We demonstrate that spatial variations in delta15N are strongly correlated with NO(x) emissions from surrounding stationary sources and additionally that delta15N is more strongly correlated with surrounding stationary source NO(x) emissions than pH, SO4(2-), or NO3- concentrations. Although emission inventories indicate that vehicle emissions are the dominant NO(x) source in the eastern U.S., our results suggest that wet NO3- deposition at sites in this study is strongly associated with NO(x) emissions from stationary sources. This suggests that large areas of the landscape potentially receive atmospheric NO(y) deposition inputs in excess of what one would infer from existing monitoring data alone. Moreover, we determined that spatial patterns in delta15N values are a robust indicator of stationary NO(x) contributions to wet NO3- deposition and hence a valuable complement to existing tools for assessing relationships between NO3- deposition, regional emission inventories, and for evaluating progress toward NO(x) reduction goals.

Combined directed ortho Metalation/Suzuki-Miyaura cross-coupling strategies. Regiospecific synthesis of chlorodihydroxybiphenyls and polychlorinated biphenyls

The Directed ortho Metalation (DoM)/Suzuki-Miyaura cross-coupling strategy is applied for the regiospecific construction of all isomeric monochloro and selected dichloro and trichloro 2,3-dihydroxybiphenyls (DHBs). The combined methodology highlights iterative DoM processes, hindered Suzuki-Miyaura couplings, and advantages in diversity in approaches from commercial starting materials leading to provision of chloro-DHBs as single isomers in high purity and on a gram scale. The syntheis of several PCBs are also reported.

Raman spectroscopy: elucidation of biochemical changes in carcinogenesis of oesophagus

Several techniques are under development to diagnose oesophageal adenocarcinoma at an earlier stage. We have demonstrated the potential of Raman spectroscopy, an optical diagnostic technique, for the identification and classification of malignant changes. However, there is no clear recognition of the biochemical changes that distinguish between the different stages of disease. Our aim is to understand these changes through Raman mapping studies. Raman spectral mapping was used to analyse 20-microm sections of tissue from 29 snap-frozen oesophageal biopsies. Contiguous haematoxylin and eosin sections were reviewed by a consultant pathologist. Principal component analysis was used to identify the major differences between the spectra across each map. Pseudocolour score maps were generated and the peaks of corresponding loads identified enabling visualisation of the biochemical changes associated with malignancy. Changes were noted in the distribution of DNA, glycogen, lipids and proteins. The mean spectra obtained from selected regions demonstrate increased levels of glycogen in the squamous area compared with increased DNA levels in the abnormal region. Raman spectroscopy is a highly sensitive and specific technique for demonstration of biochemical changes in the carcinogenesis of Barrett's oesophagus. There is potential for in vivo application for real-time endoscopic optical diagnosis.

The use of Raman spectroscopy to differentiate between different prostatic adenocarcinoma cell lines

Raman spectroscopy (RS) is an optical technique that provides an objective method of pathological diagnosis based on the molecular composition of tissue. Studies have shown that the technique can accurately identify and grade prostatic adenocarcinoma (CaP) in vitro. This study aimed to determine whether RS was able to differentiate between CaP cell lines of varying degrees of biological aggressiveness. Raman spectra were measured from two well-differentiated, androgen-sensitive cell lines (LNCaP and PCa 2b) and two poorly differentiated, androgen-insensitive cell lines (DU145 and PC 3). Principal component analysis was used to study the molecular differences that exist between cell lines and, in conjunction with linear discriminant analysis, was applied to 200 spectra to construct a diagnostic algorithm capable of differentiating between the different cell lines. The algorithm was able to identify the cell line of each individual cell with an overall sensitivity of 98% and a specificity of 99%. The results further demonstrate the ability of RS to differentiate between CaP samples of varying biological aggressiveness. RS shows promise for application in the diagnosis and grading of CaP in clinical practise as well as providing molecular information on CaP samples in a research setting.

Raman spectral mapping in the assessment of axillary lymph nodes in breast cancer

This paper is the first reported description of Raman Spectroscopy in the assessment of axillary lymph nodes in breast cancer patients. Raman Spectroscopy is an inelastic scattering spectroscopic technique appropriate for the assessment of unprocessed complex biological tissues. Spectra represent biochemical signatures of the tissue under scrutiny. The described method of Raman spectral mapping produces false-color spectral images of lymph node sections. These can be compared with standard histopathology slides and white light images of nodal tissue. This method has the potential to allow the detailed biochemical assessment of heterogeneous lymph node features, and to contribute towards the development of an optical diagnostic tool for use in a clinical setting.

p53 Expression and keratinocyte hyperproliferation in middle ear cholesteatoma

Keratinocytes in middle ear cholesteatoma have hyperproliferative properties. There is controversy regarding the role of p53 and its effect on cellular proliferation in cholesteatoma. This study was instituted to examine this. Cholesteatoma and deep meatal skin control specimens were analysed for MIB-1 (n = 7, controls = 7), a marker of cellular proliferation, and p53 (n = 17, controls = 17) expression by immunocytochemistry. Expression of p53 was minimal or absent in both cholesteatoma and controls (P = 0.2). MIB-1 expression was higher, but not significantly so, in cholesteatoma than in controls (P = 0.09). Our study has shown no significant p53 expression in cholesteatoma epithelium. This suggests that there is no dysfunction in the p53-mediated cell cycle control mechanisms in cholesteatoma.

Levels of mercury in alligators (Alligator mississippiensis) collected along a transect through the Florida Everglades

As part of a multi-agency study of alligator health, 28 American alligators (Alligator mississippiensis) were captured along a transect through the Florida Everglades in 1999. Liver and tail muscle tissues were sampled and analyzed on a wet weight basis for total mercury (THg) using cold-vapor atomic absorption spectrophotometry. All tissues had detectable concentrations of THg that ranged from 0.6 to 17 mg/kg in liver and from 0.1 to 1.8 mg/kg in tail muscle. THg was more concentrated in liver tissue than tail muscle, but levels were highly correlated between tissues. THg concentrations in tissue differed significantly among locations, with animals from Everglades National Park (ENP) having mean concentrations of THg in liver (10.4 mg/kg) and tail muscle (1.2 mg/kg) that were two-fold higher than basin-wide averages (4.9 and 0.64 mg/kg, respectively). The reasons for higher contamination of ENP alligators were unclear and could not be explained by differences in sex, length, weight or animal age. While delta15N values were positively correlated with THg concentrations in tail muscle, spatial patterns in isotopic composition did not explain the elevated THg levels in ENP alligators. Therefore, it appears that ENP alligators were more highly exposed to mercury in their environment than individuals in other areas. Comparisons to a previous survey by Yanochko et al. [Arch Environ Contam Toxicol 32 (1997) 323] suggest that mercury levels have declined in some Everglades alligators since 1994.

Altered expression of apolipoprotein E, amyloid precursor protein and presenilin-1 is associated with chronic reactive gliosis in rat cortical tissue

A major characteristic feature of Alzheimer's disease is the formation of compact, extracellular deposits of beta-amyloid (senile plaques). These deposits are surrounded by reactive astrocytes, microglia and dystrophic neurites. Mutations in three genes have been implicated in early-onset familial Alzheimer's disease. However, inflammatory changes and astrogliosis are also believed to play a role in Alzheimer's pathology. What is unclear is the extent to which these factors initiate or contribute to the disease progression. Previous rat studies demonstrated that heterotopic transplantation of foetal cortical tissue onto the midbrain of neonatal hosts resulted in sustained glial reactivity for many months. Similar changes were not seen in cortex-to-cortex grafts. Using this model of chronic cortical gliosis, we have now measured reactive changes in the levels of the key Alzheimer's disease proteins, namely the amyloid precursor protein, apolipoprotein E and presenilin-1. These changes were visualised immunohistochemically and were quantified by western blot analysis. We report here that chronic cortical gliosis in the rat results in a sustained increase in the levels of apolipoprotein E and total amyloid precursor protein. Reactive astrocytes in heterotopic cortical grafts were immunopositive for both of these proteins. Using a panel of amyloid precursor protein antibodies we demonstrate that chronic reactive gliosis is associated with alternative cleavage of the peptide. No significant changes in apolipoprotein E or amyloid precursor protein expression were seen in non-gliotic cortex-to-cortex transplants. Compared to host cortex, the levels of both N-terminal and C-terminal fragments of presenilin-1 were significantly lower in gliotic heterotopic grafts.The changes described here largely mirror those seen in the cerebral cortex of humans with Alzheimer's disease and are consistent with the proposal that astrogliosis may be an important factor in the pathogenesis of this disease.

From 'culture of dehumanization of childbirth' to 'childbirth as a transformative experience': changes in five municipalities in north-east Brazil

Brazil has become a country known as having one of the most extreme examples of the consequences of the hospital-based medicalization of delivery care, while a model of humanization of birth was developed in the State of Ceará in the 1970s. The Government of Japan, through the Japanese International Cooperation Agency (JICA), collaborated with the Federal Ministry of Health of Brazil and the Government of the State of Ceará, in implementing the Maternal and Child Health Improvement Project in north-east Brazil (1996-2001). This project focused on 'humanization of childbirth', with training based intervention activities. Behavioral changes among health professionals who received the project's participatory type of training were described using rapid anthropological assessment procedure (RAP) survey results. Changes from 'a culture of dehumanization of childbirth' to 'childbirth as a transformative experience' were observed.

Tandem zirconocene homologation-aldimine allylation

[reaction: see text]. Hydrozirconation of internal and terminal alkynes followed by in situ transmetalation to dimethylzinc and treatment with diiodomethane leads to chain extended allylic organometallics. Addition to N-phosphinoyl or N-sulfonyl aldimines provides homoallylic amines in 48-87% yield and 3:2 to >20:1 diastereomeric ratios favoring anti-products.

Review article: the potential role for photodynamic therapy in the management of upper gastrointestinal disease

Photodynamic therapy involves the activation of an exogenously administered, or an endogenously generated, photosensitizer with light to produce localized tissue destruction. It is an attractive, predominantly endoscopic technique for the palliation of advanced upper gastrointestinal cancer and the eradication of early neoplastic and pre-neoplastic lesions. The nature of the biological response allowing safe healing and the exploitation of tissue threshold effects mean that adjacent tissue damage can be minimized. This review used a database of 368 papers. The nature of the photosensitizer is critical to the depth of tissue damage and the risk of adjacent tissue damage and stricture formation. The generation of protoporphyrin IX following administration of 5-aminolaevulinic acid has proved useful for the treatment of high-grade dysplasia in Barrett's oesophagus. A double-blind randomized placebo controlled trial has confirmed that it is a safe and effective method for the ablation of low-grade dysplasia. The treatment of more advanced lesions requires exogenously administered photo-sensitizers. However, recent data indicate that the neoplastic potential remains in some patients and continued follow-up is necessary. Photodynamic therapy can be used to eradicate early neoplasia and palliate advanced cancer, but caution is required before a definitive cure can be claimed.

Are p53 and MIB-1 overexpressed in cholesteatoma?

INTRODUCTION: There is controversy regarding the expression of p53 and MIB-1 in cholesteatoma.1 This study was instituted to study this. p53 is an intracellular protein which plays a critical role in control of the cell cycle at the G1 check point. MIB-1 is recognized as a marker of cellular proliferation. Using deep meatal skin controls, the question addressed was, 'are p52 and MIB-1 overexpressed in cholesteatoma'? METHOD: Immunocytochemistry using the avidin-biotin technique on frozen tissue sections with primary antibody to p53 (n = 17, controls = 17) and MIB (n = 17, controls = 7) was performed on cholesteatoma and deep meatal skin control specimens. Appropriate positive and negative controls were employed for each antibody. Slides were analysed in a blind fashion by two independent observers. Statistical analysis was performed using the Mann-Whitney test. RESULTS: Expression of p53 was minimal or absent in both cholesteatoma and controls. No significant difference in p53 expression was found between the two groups (P = 0.02). MIB-1 expression was higher in cholesteatoma than in controls, although this was not statistically significant (P = 0.09). CONCLUSION: This study did not demonstrate an increased expression of p53 cholesteatoma, indicating no evidence of a dysfunctional cell cycle. MIB-1 results showed a possible trend towards significance, which requires a more powerful study to evaluate this further. The probability that there is an increased rate of cellular proliferation in cholesteatoma, when compared to deep meatal skin controls, cannot be excluded.

Raman spectroscopy for early detection of laryngeal malignancy: preliminary results

OBJECTIVE

Raman spectroscopy, the analysis of scattered photons after monochromatic laser excitation, is well established in nonbiological sciences. Recently this method has been used to differentiate premalignant and malignant lesions from normal tissue. Its application for early diagnosis has been explored in a variety of sites (e.g., esophagus, cervix), but not, to date, in laryngeal cancer. The objective of this study was to perform a feasibility study of the use of Raman spectroscopy for early diagnosis of laryngeal malignancy.

METHODS

Biopsy specimens were snap-frozen, and top sections were sent for histopathological analysis. Only homogenous samples with clearly defined pathological findings were used in this study: seven histologically normal samples, four exhibiting dysplasia, and four with carcinoma. Samples were defrosted and placed under a Renishaw (Wotton-Under-Edge, UK) System 1000 Raman microspectrometer for analysis. Between 5 and 12 spectra were acquired from each sample, with an excitation wavelength of 830 nm. Average characteristic spectra for each disease or condition were compared. Further multivariate statistical analysis of the data was carried out to evaluate and maximize the differences in the spectra for each disease or condition.

RESULTS

The most visible differences in the spectra occur between 850 and 950 cm(-1) and 1,200 and 1,350 cm(-1). The later peaks are directly related to protein conformation and C-H bond stretch in nucleic acid bases. The relative intensity of the nucleic acid peak increases with progression to malignancy. Use of linear discriminant analysis made it possible to separate the spectra with disease to a greater degree of accuracy than using empirical peak ratio methods alone. Classification results obtained from cross-validation of the discriminant model showed prediction sensitivities of 83%, 76%, and 92% and specificities of 94%, 91%, and 90% for normal, dysplastic, and squamous cell carcinoma of the larynx, respectively.

CONCLUSIONS

There was strong evidence to support spectral identification of malignancy and earlier abnormal changes. More substantive studies of the spectral differences between malignant and non-neoplastic tissue are warranted. Raman spectroscopy may become a useful adjunct to pathological diagnosis allowing directed or guided biopsies and assessment of adequacy of resection margins.

Use of health status measures in patients with low back pain in clinical settings. Comparison of specific, generic and preference-based instruments

OBJECTIVE

To evaluate the discriminative performance over time of specific, generic and preference-based instruments in patients with low back pain (LBP) in clinical settings.

METHODS

Forty-six consecutive patients with LBP participated in the study. Self-response questionnaires were administered at baseline and 3 and 6 months, including the following instruments: Oswestry (specific for LBP), SF-36 (generic), EuroQol (EQ-5D) and Health Utilities Index (HUI) (preference-based). EQ-5D and HUI weights were derived from previously published evaluations in the general population. Patients were asked to compare their health status with their baseline health and were categorized on the basis of an ordinal scale as: (a) improved; (b) stable; or (c) worse. Changes in the instruments were evaluated by rescaling the instruments over the same scale interval and by estimating standardized effect sizes between two time points for the three categories of change.

RESULTS

Thirty-seven patients (80%) completed both the baseline and the 3-month questionnaire and 34 the baseline and 6-month questionnaires (74%). Overall, at both time points, approximately half of the patients reported no changes in their health status. Correlations between instruments were generally low, suggesting that they measure different health domains. The scales which discriminated best between patients who improved and those who deteriorated at 3 months were the Oswestry, the HUI, the EQ-5D and the SF-36 bodily pain and emotional role subscales. The SF-36 subscales appeared to have a floor effect for those patients who had deteriorated.

CONCLUSIONS

Most SF-36 subscales did not adequately reflect changes in the health status of patients with LBP, mostly for those who reported deterioration. Preference-derived quality-of-life scores appeared to discriminate among patients who improved and those who deteriorated, although not as consistently as the disease-specific measure (Oswestry). Additional research is needed to evaluate the role of generic measures of quality of life in the assessment of patients with LBP before they can be widely implemented in clinical settings or outcomes research.

Social network influences on reproductive health behaviors in urban northern Thailand

Prevention approaches for reproductive health have evolved from an emphasis on individually focused models of behavior change to a recognition that risk reduction occurs within a context of social norms. Prevention programs can be improved by understanding how social structure influences sexual behavior and using that understanding to develop strategies for positive change. In a dynamic, urban context, communities are better conceptualized as informal networks of ties. These network structures may help to protect, or conversely, expose members to reproductive risk behaviors. Using data from a study of social and sexual networks conducted in northern Thailand, this article describes partner relations and social structure in the modern, urban context, and illustrates the links between individual, relational and structural properties and reproductive risk behaviors. Triangulation of ethnographic, survey and social network data collection and analytic tools provide an opportunity to interpret individual behaviors, meanings of relationships and structural properties of networks. Intervention approaches should build on existing networks, and address the complex meanings of romantic and sexual partnerships.

The relative effectiveness of three reminder letters. On making and keeping mammogram appointments

One hundred fifty women who had previously had at least one mammogram were sent one of three prompt letters informing them that they were due for screening. The letters were either reassuring, anxiety provoking, or the standard hospital prompt. Based on a review of the literature, we hypothesized that the reassuring letter would be most effective in motivating women to schedule and keep appointments, the anxiety-provoking letter would produce an intermediate level fo compliance, and the standard hospital letter would be least effective. Our hypothesis was partially supported. Overall, 45% of the women in the study scheduled mammogram appointments. This included 54% of those who received the reassuring letter, 42% of those who received the anxiety provoking letter, and 38% of those who received the standard letter. Although the results were in the predicted direction, the results of a chi-square test indicated that differences among groups were not statistically significant. When the dependent measure was number of appointments kept, rather than scheduled, however, significantly more women who received the reassuring letter actually kept their appointments compared with those who received the standard hospital letter. Subsequent analyses suggested that having a family history of breast cancer, receiving a reassuring letter, and being older than 50 years were important factors in scheduling appointments.

Networks of persons with syphilis and at risk for syphilis in Louisiana: evidence of core transmitters

BACKGROUND AND OBJECTIVES

Differences in sociodemographic attributes and healthcare access may explain differences in regional sexually transmitted disease rates but don't fully explain why syphilis persists disproportionately in certain populations.

GOAL OF THIS STUDY

To understand the behavioral epidemiology of syphilis, we conducted a social network analysis of persons with syphilis and their contacts and developed and applied a definition of core transmitters.

STUDY DESIGN

We interviewed 10 index persons with primary or secondary untreated syphilis and 80 of their named sexual and social contacts.

RESULTS

Fourteen (16%) of 90 interviewed persons met the definition of core transmitters, 9 of whom had past or current syphilis. The other interviewed persons had only moderately risky behaviors. Seventy-eight (42%) of the network sexual contacts were connected directly or indirectly to a core transmitter.

CONCLUSION

This analysis suggests that syphilis transmission is maintained by a community with a small percentage of high-risk persons centrally placed amidst a larger group with moderately risky behavior.

Implementation of condom social marketing in Louisiana, 1993 to 1996

OBJECTIVES

This article describes the implementation and impact of the first statewide condom social marketing intervention in the United States.

METHODS

A statewide social marketing program made condoms freely available in 93 public health clinics, 39 community mental health centers, 29 substance abuse treatment sites, and more than 1000 businesses in neighborhoods with high rates of sexually transmitted diseases (STDs) and HIV. Surveys about condom use were conducted annually.

RESULTS

Between 1994 and 1996, more than 33 million condoms were distributed without significant opposition. Over time, self-reported condom use at the last sexual encounter increased among African American women (from 28% in 1994 to 36% in 1996), particularly African American women with 2 or more sex partners (from 30% to 48%). Condom use at the last sexual encounter increased among African American men (from 40% in 1994 to an average of 54% in 1996). The number of reported sex partners did not increase.

CONCLUSIONS

Condom social marketing can be successfully implemented in the United States. The widespread availability of free condoms is associated with increased condom use, particularly among persons at high risk for STDs and HIV.

Feces, flies, and fetor: findings from a Peruvian shantytown

Sanitary disposal of feces is vital to combat childhood diarrhea, and its promotion is key to improving health in developing countries. Knowledge of prevailing feces disposal practices is a prerequisite to formulation of effective intervention strategies. Two studies were conducted in a shantytown area of Lima, Peru. First, information was gathered through in-depth interviews with mothers and structured observations (4 hours) of young children and their caretakers. Data on beliefs and practices related to feces disposal behaviors were obtained. Excreta were deposited by animals or humans in or near the house in 82% of households observed. Beliefs about feces depended on their source and were reflected in how likely the feces were to be cleared. While 22% of children aged > or = 18 months were observed to use a potty for defecation, 48% defecated on the ground where the stools often remained. Although almost all children were cleaned after defecation, 30% retained some fecal matter on their body or clothes. Handwashing after the child's defecation was extremely rare for both children (5%) and caretakers (20%). The hygienic disposal of feces poses problems in this type of community. Nevertheless existing practices were found that show promise for promotion on a wider scale, including greater use of potties.

Troubleshooting the postoperative IOL result

1. We all experience disappointment when a patient's postoperative visual result differs from the anticipated refraction. Although it is easy to initially place blame on an A-scan measurement, keratometer reading or an incorrect IOL calculation, our frustration may be tempered by applying a few basic troubleshooting steps. 2. There are several reasons for determining the cause for the discrepancy. First is to address the potential need for an IOL exchange if the refraction is dramatically unacceptable. Second, information gained from analysis of the first eye's results can aid in more accurately predicting an IOL power for the patient's fellow eye. A third reason is to learn from our mistakes to prevent their recurrence. A step-by-step analysis provides an unemotional method for reaching a much needed conclusion. 3. Ask yourself the following questions: Do pre- and postoperative measurements make sense and correlate with patient history? Are A-scan echo patterns and electronic caliper placement correct? Have correct values been entered into the formula?

The Yoruba farm market as a communication channel in guinea worm disease surveillance

Disease eradication programmes are by definition time bound and require strategies that facilitate timely intervention. Surveillance, which undergirds eradication, also requires timely strategies. Finding such strategies is especially challenging when the target disease is endemic in remote areas, e.g. guinea worm disease, the focus of this study. A strategy of market based surveillance was pilot tested in Ifeloju Local Government Area (LGA) of Oyo State, Nigeria. The project goal was to design a surveillance system that both fit into the natural communication network of rural people, and also enlisted their active involvement. Ethnographic research methods were employed to learn about market location, structure, catchment area and attendance pattern. Four larger farm markets (serving 164 hamlets with 17,000 population) were chosen. Each hamlet was visited and a volunteer 'reporter' was recruited. Reporters were trained on case recognition and detection, first aid and prevention, with a sensitivity to distinguishing indigenous and clinical perceptions of guinea worm. The market cycle was based on the traditional four-day week. Field workers visited every second market 16 times between October 1990 and February 1991. The reporter was expected to identify correctly the first case of the season and thus label the village as endemic for the season. Reporters gave oral reports, and positive indications were followed up within 48 hr by field workers, who verified the case and administered first aid. All hamlets were visited once a month to verify negative reports. Reporter attendance was monitored. Those who had a formal role in the market, e.g. sales agents, had better attendance than ordinary farmers who came only to sell their own produce. Knowledge of market structure and attender roles offers a guide for adapting this surveillance approach to other cultural systems and health issues.

Testing strategies to increase use of chloroquine chemoprophylaxis during pregnancy in Malaŵi

The widespread problem of low and non-compliance to antimalarial chemoprophylaxis during pregnancy demands that attention be focused on alternative approaches to programming, product acceptability and demand for preventive services. This study describes the testing of three interventions to determine their effect on use of chloroquine (currently the most widely used drug for chemoprophylaxis) during pregnancy. The strategies evolved from community-based formative research undertaken to learn about the local concept of malaria and issues surrounding malaria prevention and treatment during pregnancy. The resulting interventions were tested in four clinics, and included a change in the health education message given during antenatal sessions, distribution of a sugar-coated chloroquine tablet, and an intervention combining the two strategies. The results showed a 45% increase in chloroquine use when the health education message was changed, and a 64% increase when the product was changed. High use levels were maintained with the combined intervention; an additive effect was seen. The study shows that improving the product was the most important factor in increasing the use of the program, and that changing the health education message can also make an impact on use.

The design of a community-based health education intervention for the control of Aedes aegypti

This report describes the process used to develop locally appropriate educational materials and to implement the education component of a community-based Aedes aegypti control program in Merida, Yucatan, Mexico. The process is broken into five stages: formative research, developing recommendations for behavior change, development of educational messages, development and production of educational materials, and distribution of the materials. Appropriate terminology and taxonomies for dengue were obtained from open in-depth interviews; baseline data from a knowledge, beliefs, and practices questionnaire served to confirm this information. A larval survey of house lots was carried out to identify the Ae. aegypti larval production sites found on individual house lots. This enabled the program to target the most important larval habitats. Community groups were organized to work on the development of messages and production of the educational materials to be used. The education intervention was successful in stimulating changes in both knowledge and behavior, which were measured in the evaluations of the intervention. To be successful, community-based strategies must be flexible and adapted to the local setting because of ecologic, cultural, and social differences between localities.

The household production of health: integrating social science perspectives on micro-level health determinants

Efforts to control disease and improve health in developing countries require increasing collaboration between social and medical scientists. This collaboration should extend from the early stages of technology development to the evaluation and improvement of population-wide interventions. This paper provides an integrating framework for social science research on health producing processes at the household level, drawing on recent work in economics, anthropology, and public health. Further development of theory and methods in this area would benefit from interdisciplinary research in categories as defined by social and behavioral science in addition to those related to specific diseases and intervention programs.