Vitamin D and Omega 3 Field Study on Progression of Type 1 Diabetes

Chronic inflammation has been linked to the progression of type 1 diabetes (T1D). Supplementation with vitamin D and omega-3 fatty acids, which have anti-inflammatory properties, may slow or stop the progression of T1D. A field study is underway to assess the relationship between these nutrients and T1D progression among auto-antibody positive individuals who have not been diagnosed with T1D. The T1D Prevention Field Study is currently recruiting participants to complete online health surveys and home blood-spot tests for 25-hydroxyvitamin D [25(OH)D], Omega-3 Index, AA:EPA Ratio, high-sensitivity C-reactive protein, and HbA1c every three to four months for 5 years. Participants (or their parents/guardians) are given information about the importance of achieving a 25(OH)D level between 40-60 ng/ml and an AA:EPA Ratio between 1.5-3.0 to reduce inflammation. However, participants are free to choose their own supplement or dietary regimens. Data analysis will focus on associations between vitamin D and omega-3 status and progression of T1D. Initial enrollment in the T1D Prevention Field Study includes 103 participants from fifteen countries; total enrollment is expected to reach at least 400 participants by the end of 2022. The field study approach allows for cost-effective research that capitalizes on new technologies for recruitment, data collection, and blood level testing from home. However, some challenges have arisen. Many individuals are reading the open source protocols and some choose to supplement and test on their own so incentives may be needed to increase enrollment. Additionally, some participants do not have access to auto-antibody testing or are unable to get access to their test results; therefore, there is a need to provide blood spot auto-antibody testing through the field study.

Diagnostic accuracy of midtrimester antenatal ultrasound for multicystic dysplastic kidneys

OBJECTIVES

To establish the diagnostic accuracy of obstetric ultrasound at a tertiary fetal medicine center in the prenatal detection of unilateral and bilateral multicystic dysplastic kidney (MCDK) in fetuses in which this condition was suspected, and to undertake a systematic review of the relevant literature.

METHODS

This was a retrospective observational study of all cases referred to a regional tertiary fetal medicine unit due to suspicion of either unilateral or bilateral MCDK between 1997 and 2015. Diagnosis was confirmed by postnatal ultrasound reports or postmortem examination. The accuracy of prenatal ultrasound in the diagnosis of MCDK was calculated. Using a systematic search strategy we also performed a review of the literature regarding the prenatal diagnosis and diagnostic accuracy of MCDK.

RESULTS

We included 144 women in our analysis; 37 (25.7%) opted for pregnancy termination (TOP) (due to unilateral MCDK with additional abnormalities, suspected bilateral MCDK or severe obstructive uropathy). Complete pre- and postnatal data were available in 126 pregnancies, including 104 livebirths, 19 TOPs with postmortem findings available and three intrauterine fetal deaths. Two infants died shortly after birth (due to known bilateral MCDK or known cranial vault defect). The overall number of cases of MCDK confirmed postnatally was 100; of these, 98 were diagnosed prenatally (true positive), while two were thought to be hydronephrosis prenatally (false negative) and the diagnosis of MCDK was made after birth. In nine cases, the initial antenatal diagnosis of suspected MCDK was revised, either later in pregnancy (n = 2) or postnatally (n = 7) (false positive). Overall, the diagnostic accuracy in our population for the use of antenatal ultrasound to detect MCDK was 91.3%, while that reported in the existing literature was found to range from 53.3% to 100%. MCDK was isolated in the majority (71%) of cases, while in 29% of cases it was found to be associated with other renal and extrarenal fetal abnormalities.

CONCLUSIONS

Antenatal ultrasound had a diagnostic accuracy of about 91% in the prediction of postnatal MCDK and can therefore be used to guide antenatal counseling. However, prenatal or postnatal revision of the diagnosis occurred in about 7% of cases and parents should be counseled appropriately. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Post-hoc analysis of vitamin D status and reduced risk of preterm birth in two vitamin D pregnancy cohorts compared with South Carolina March of Dimes 2009-2011 rates

BACKGROUND

Two vitamin D pregnancy supplementation trials were recently undertaken in South Carolina: The NICHD (n=346) and Thrasher Research Fund (TRF, n=163) studies. The findings suggest increased dosages of supplemental vitamin D were associated with improved health outcomes of both mother and newborn, including risk of preterm birth (<37 weeks gestation). How that risk was associated with 25(OH)D serum concentration, a better indicator of vitamin D status than dosage, by race/ethnic group and the potential impact in the community was not previously explored. While a recent IOM report suggested a concentration of 20 ng/mL should be targeted, more recent work suggests optimal conversion of 25(OH)D-1,25(OH)2D takes place at 40 ng/mL in pregnant women.

OBJECTIVE

Post-hoc analysis of the relationship between 25(OH)D concentration and preterm birth rates in the NICHD and TRF studies with comparison to Charleston County, South Carolina March of Dimes (CC-MOD) published rates of preterm birth to assess potential risk reduction in the community.

METHODS

Using the combined cohort datasets (n=509), preterm birth rates both for the overall population and for the subpopulations achieving 25(OH)D concentrations of ≤20 ng/mL, >20 to <40 ng/mL, and ≥40 ng/mL were calculated; subpopulations broken down by race/ethnicity were also examined. Log-binomial regression was used to test if an association between 25(OH)D serum concentration and preterm birth was present when adjusted for covariates; locally weighted regression (LOESS) was used to explore the relationship between 25(OH)D concentration and gestational age (weeks) at delivery in more detail. These rates were compared with 2009-2011 CC-MOD data to assess potential risk reductions in preterm birth.

RESULTS

Women with serum 25(OH)D concentrations ≥40 ng/mL (n=233) had a 57% lower risk of preterm birth compared to those with concentrations ≤20 ng/mL [n=82; RR=0.43, 95% confidence interval (CI)=0.22,0.83]; this lower risk was essentially unchanged after adjusting for covariates (RR=0.41, 95% CI=0.20,0.86). The fitted LOESS curve shows gestation week at birth initially rising steadily with increasing 25(OH)D and then plateauing at ∼40 ng/mL. Broken down by race/ethnicity, there was a 79% lower risk of preterm birth among Hispanic women with 25(OH)D concentrations ≥40 ng/mL (n=92) compared to those with 25(OH)D concentrations ≤20 ng/mL (n=29; RR=0.21, 95% CI=0.06,0.69) and a 45% lower risk among Black women (n=52 and n=50; RR=0.55, 95% CI=0.17,1.76). There were too few white women with low 25(OH)D concentrations for assessment (n=3). Differences by race/ethnicity were not statistically significant with 25(OH)D included as a covariate. Compared to the CC-MOD reference group, women with serum concentrations ≥40 ng/mL in the combined cohort had a 46% lower rate of preterm birth overall (n=233, p=0.004) with a 66% lower rate among Hispanic women (n=92, p=0.01) and a 58% lower rate among black women (n=52, p=0.04).

CONCLUSIONS

In this post-hoc analysis, achieving a 25(OH)D serum concentration ≥40 ng/mL significantly decreased the risk of preterm birth compared to ≤20 ng/mL. These findings suggest the importance of raising 25(OH)D levels substantially above 20 ng/mL; reaching 40 ng/mL during pregnancy would reduce the risk of preterm birth and achieve the maximal production of the active hormone.

Molecular basis of invasion in breast cancer

Cancer cell invasion involves the breaching of tissue barriers by cancer cells, and the subsequent infiltration of these cells throughout the surrounding tissue. In breast cancer, invasion at the molecular level requires the coordinated efforts of numerous processes within the cancer cell and its surroundings. Accumulation of genetic changes which impair the regulation of cell growth and death is generally accepted to initiate cancer. Loss of cell-adhesion molecules, resulting in a loss in tissue architecture, in parallel with matrix remodelling may also confer a motile or migratory advantage to breast cancer cells. The tumour microenvironment may further influence the behaviour of these cancer cells through expression of cytokines, growth factors, and proteases promoting chemotaxis and invasion. This review will attempt to summarise recent work on these fundamental processes influencing or facilitating breast cancer cell invasion. (Part of a Multi-author Review).

Reduced penetrance alleles for Huntington's disease: a multi-centre direct observational study

OBJECTIVE

To obtain penetrance data for Huntington's disease when DNA results are in the range of 36-39 CAG repeats and assess the consistency of reporting the upper allele from two reference centres.

METHOD

Data were collected anonymously on age of onset or age last known to be unaffected from a cohort of individuals with results in this range. DNA samples were re-analysed in two reference centres. Kaplan-Meier analysis was used to construct an age of onset curve and penetrance figures.

RESULTS

Clinical data and concordant DNA results from both reference centres were available for 176 samples; penetrance figures (and 95% confidence intervals) for this cohort, at age 65 and 75 years, were 63.9% (55.5% to 73.2%) and 74.2% (64.2% to 84.2%), respectively. Inclusion of 28 additional subjects for whom repeat DNA results were unavailable, obtained from only one reference centre, or discrepant by one repeat within this range, gave penetrance data (including 95% confidence intervals) at ages 65 and 75 years of 62.4% (54.4% to 70.4%) and 72.7.% (63.3% to 82.1%), respectively. 238 duplicate results were available from the reference centres; 10 (4.2%) differed by one CAG repeat in the reporting of the upper allele and in two (0.84%) of these cases the discrepancy was between 39 and 40 repeats.

CONCLUSION

When DNA results are in this range, a conservative approach is to say that there is at least a 40% chance the person will be asymptomatic at age 65 years and at least a 30% chance the person will be asymptomatic at age 75 years.

Pharmacokinetics of boldenone and stanozolol and the results of quantification of anabolic and androgenic steroids in race horses and nonrace horses

Anabolic steroids (ABS) boldenone (BL; 1.1 mg/kg) and stanozolol (ST; 0.55 mg/kg) were administered i.m. to horses and the plasma samples collected up to 64 days. Anabolic steroids and androgenic steroids (ANS) in plasma were quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The limit of detection of all analytes was 25 pg/mL. The median absorption (t1/2 partial differential) and elimination (t1/2e) half-lives for BL were 8.5 h and 123.0 h, respectively, and the area under the plasma concentration-time curve (AUCho) was 274.8 ng.h/mL. The median t1/2e for ST was 82.1 h and the was 700.1 ng.h/mL. Peak mean (X+/-SD) plasma concentrations (Cmax) for BL and ST were 1127.8 and 4118.2 pg/mL, respectively. Quantifiable concentrations of ABS and ANS were found in 61.7% of the 988 plasma samples tested from race tracks. In 17.3% of the plasma samples two or more ABS or ANS were quantifiable. Testosterone (TES) concentrations mean (X+/-SE) in racing and nonracing intact males were 241.3+/-61.3 and 490.4+/-35.1 pg/mL, respectively. TES was not quantified in nonracing geldings and female horses, but was in racing females and geldings. Plasma concentrations of endogenous 19-nortestosterone (nandrolone; NA) from racing and nonracing males were 50.2+/-5.5 and 71.8+/-4.6 pg/mL, respectively.

Increasing film-focus distance (FFD) reduces radiation dose for x-ray examinations

Increasing film-focus distance (FFD) from the traditional 100 cm has been shown to be an effective method of reducing dose whilst maintaining image quality. In particular, previous work increasing the FFD from 100 to 130 cm for lumbar spine examinations demonstrated an effective dose reduction of 44%. Objective. The current study continues on from this work by investigating the dose-reducing efficacy of this FFD change for pelvis X-ray examinations. Materials and methods. Dose measurements at 100 and 130 cm using thermoluminescent dosemeters were undertaken using an anthropomorphic phantom and patients. Image quality was assessed using CEC anatomical criteria and psychophysical tests. Results. The results showed that increasing the FFD results in a reduction in effective dose of 33%, with no change in image quality. The data provided in this and previous studies demonstrate the need for rapid implementation of this simple cost-effective procedure across imaging departments, leading to an important reduction in collective dose. Conclusion. The CEC recommendation of using 115 cm FFD for a number of procedures, although useful compared with 100 cm, undervalues by a factor between 2 and 3 the potential of this dose-reducing tool.

A complex rearrangement involving simultaneous translocation and inversion is associated with a change in chromatin compaction

Detailed fluorescence in situ hybridisation analysis of a previously described translocation revealed it to be a more complex rearrangement consisting of both a translocation and a paracentric inversion with an apparent coincident breakpoint at 16p13.3, t(14;16)(p32;p13.3) inv16(p13.3p12.1). This unusual three-breakpoint rearrangement was not obvious from examination of G-banding. Such rearrangements may be undiagnosed in cytogenetic studies. The presence of an interstitial deletion of 16p was unlikely as the rearranged chromosome contained probes distributed along the short arm of chromosome 16. Fluorescence in situ hybridisation studies suggested that the inverted segment was smaller in size than that on the normal chromosome. Measurements of distances between probes on metaphase chromosomes confirmed that there was differential compaction of the inverted portion on 16p. The inverted region was significantly reduced in size by 21% compared with the same region on the normal chromosome 16. The size reduction across the region was non-uniform, with one region showing a 55% increase in compaction. The change in compaction was also associated with a change in the lateral position of a probe on the chromatids. The finding that a single chromosome breakpoint can change the compaction of chromatin over an extensive region has implications for models of the structure of metaphase chromosomes. Possible explanations are either a localized severe disruption of DNA packaging over relatively short distances (hundreds of kilobases) or a more generalized change that extends over many megabases. These results raise the important possibility that chromosome breaks may result in a more global change in DNA compaction across large segments of a chromosome.

Examining the relationship between cancer invasion/metastasis and drug resistance

Studies of cancer invasion/metastasis and drug resistance have in the past generally proceeded along the separate pathways of research. Recently, however, interest has been focused on the possible relationship between drug resistance and cancer invasion and metastasis. A relationship between these two phenotypes has been demonstrated by two types of observation: firstly, some tumor cells selected for resistance to drugs are more invasive/metastatic relative to non-resistant parental cells; secondly, in some cases, secondary (more metastatic) tumors are more resistant to chemotherapeutic drugs than their primary counterparts. In other instances reported in the literature, no correlation is seen between drug exposure/resistance and cancer invasion/metastasis. The possibility that treatment with some chemotherapeutic drugs may be able to promote cancer invasion and metastasis needs further investigation because of its potential clinical relevance. A better understanding of any relationship between drug resistance and cancer invasion could lead to more effective cancer treatment.

Clinical features of a novel TIMP-3 mutation causing Sorsby's fundus dystrophy: implications for disease mechanism

AIMS

To describe the phenotype in three family members affected by a novel mutation in the gene coding for the enzyme tissue inhibitor of metalloproteinase-3 (TIMP-3).

METHODS

Three members of the same family were seen with a history of nyctalopia and visual loss due to maculopathy. Clinical features were consistent with Sorsby's fundus dystrophy. Exon 5 of the gene coding for TIMP-3 was amplified by the polymerase chain reaction, single strand conformation polymorphism analysis undertaken and exon 5 amplicons were directly sequenced.

RESULTS

Onset of symptoms was in the third to fourth decade. Five of six eyes had geographic macular atrophy rather than neovascularisation as a cause for central visual loss. Peripheral retinal pigmentary disturbances were present. Scotopic ERGs were abnormal in all three. Mutation analysis showed a G-->T transversion in all three resulting in a premature termination codon, E139X, deleting most of the carboxy terminal domain of TIMP-3.

CONCLUSIONS

The patients described had a form of Sorsby's fundus dystrophy which fell at the severe end of the spectrum of this disease. Postulated disease mechanisms include deposition of dimerised TIMP-3 protein.

The role of matrilysin (MMP-7) in leukaemia cell invasion

The matrix metalloproteinases (MMPs) are important in tumour cell invasion and metastasis in many common cancers. However, relatively few studies have investigated the role of MMPs and their inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), in leukaemia cell invasion. This study examined two leukaemia cell lines, K562 and HL-60 and showed that the K562 cell line was four times more invasive than the HL-60 cell line. The expression of MMP-2, matrilysin (MMP-7), MMP-9. TIMP-1, TIMP-2 and TIMP-3 was analysed. Both cell lines produced similar amounts of MMP-2, MMP-9 and TIMP-2. The K562 cells expressed more TIMP-1 than the HL-60 cells and neither cell line expressed TIMP-3. Interestingly, only the K562 cells expressed matrilysin suggesting a potential role for matrilysin in leukaemia cell invasion. in vitro invasion assays performed in the presence of a matrilysin blocking antibody showed a 40% reduction in invasive ability. This data suggests that matrilysin plays an important role in leukaemia cell invasion.

Selection with melphalan or paclitaxel (Taxol) yields variants with different patterns of multidrug resistance, integrin expression and in vitro invasiveness

A melphalan-resistant variant (Roswell Park Memorial Institute (RPMI)-2650Ml) and a paclitaxel-resistant variant (RPMI-2650Tx) of the drug-sensitive human nasal carcinoma cell line, RPMI-2650, were established. The multidrug resistance (MDR) phenotype in the RPMI-2650Tx appeared to be P-glycoprotein (PgP)-mediated. Overexpression of multidrug resistant protein (MRP) family members was observed in the RPMI-2650Ml cells, which were also much more invasive in vitro than the parental cell line or the paclitaxel-resistant variant. Increased expression of alpha(2), alpha(5), alpha(6), beta(1) and beta(4) integrin subunits, decreased expression of alpha(4) integrin subunit, stronger adhesion to collagen type IV, laminin, fibronectin and matrigel, increased expression of MMP-2 and MMP-9 and significant motility compared with the parental cells were observed, along with a high invasiveness in the RPMI-2650Ml cells. Decreased expression of the alpha(2) integrin subunit, decreased attachment to collagen type IV, absence of cytokeratin 18 expression, no detectable expression of gelatin-degrading proteases and poor motility may be associated with the non-invasiveness of the RPMI-2650Tx variant. These results suggest that melphalan exposure can result in not only a MDR phenotype, but could also make cancer cells more invasive, whereas paclitaxel exposure resulted in MDR without increasing the in vitro invasiveness in the RPMI-2650 cells.

Evidence for a prostate cancer susceptibility locus on the X chromosome

Over 200,000 new prostate cancer cases are diagnosed in the United States each year, accounting for more than 35% of all cancer cases affecting men, and resulting in 40,000 deaths annually. Attempts to characterize genes predisposing to prostate cancer have been hampered by a high phenocopy rate, the late age of onset of the disease and, in the absence of distinguishing clinical features, the inability to stratify patients into subgroups relative to suspected genetic locus heterogeneity. We previously performed a genome-wide search for hereditary prostate cancer (HPC) genes, finding evidence of a prostate cancer susceptibility locus on chromosome 1 (termed HPC1; ref. 2). Here we present evidence for the location of a second prostate cancer susceptibility gene, which by heterogeneity estimates accounts for approximately 16% of HPC cases. This HPC locus resides on the X chromosome (Xq27-28), a finding consistent with results of previous population-based studies suggesting an X-linked mode of HPC inheritance. Linkage to Xq27-28 was observed in a combined study population of 360 prostate cancer families collected at four independent sites in North America, Finland and Sweden. A maximum two-point lod score of 4.60 was observed at DXS1113, theta=0.26, in the combined data set. Parametric multipoint and non-parametric analyses provided results consistent with the two-point analysis. Significant evidence for genetic locus heterogeneity was observed, with similar estimates of the proportion of linked families in each separate family collection. Genetic mapping of the locus represents an important initial step in the identification of an X-linked gene implicated in the aetiology of HPC.

Expression of metalloproteinases and their inhibitors in human trophoblast continuous cell lines

Trophoblasts cells which are derived from the outer layer of the blastocyst have developed mechanisms by which they can invade the uterus and tap into the maternal circulation. In contrast to tumor cell invasion trophoblast invasion is precisely regulated, being confined spatially to the uterus and temporally to early pregnancy. The invasive properties manifested by trophoblasts are made possible by the secretion of proteolytic enzymes which can degrade components of the extracellular matrix (ECM). A number of investigators have shown that the matrix metalloproteinases (MMPs) are important mediators of trophoblast invasion. The two type IV collagenases, MMP-2 and MMP-9, which specifically degrade type IV collagen and gelatins have been of particular interest in this respect. In this paper we examine the expression and regulation of MMPs and their inhibitors in a series of trophoblast continuous cell lines. These cell lines, ED27, ED31, ED77, and a choriocarcinoma cell line, BeWo, were initially characterized with respect to various properties, including cytokeratin, hCG, and hPL expression. We have looked at the expression of MMPs and their inhibitors in these cell lines and their in vitro invasive behavior. Using zymography and RT-PCR we show that the trophoblast cell lines produce both MMP-2 and MMP-9, while the BeWo produce only MMP-2. Using an in vitro invasion assay the trophoblast cell lines were shown to be capable of invading while the BeWo were unable to invade. These results suggest that expression of MMP-9 in these cells is crucial for invasion. We have also examined the regulation of MMP expression by cytokines and found that MMP-9 expression could be modulated by IL-1 beta in these cell lines. The data presented in this paper suggest that these trophoblast cell lines present an ideal model system to investigate the regulation of metalloproteinases in trophoblast invasion.

Electroretinographic findings in macular dystrophy

The flash and pattern electroretinogram were investigated in a group of families with rare forms of inherited macular dystrophy, which included Sorsby's fundus dystrophy, X-linked retinoschisis and macular dystrophy of uncertain classification and variable expression. Flash electroretinograms, under both photopic and scotopic conditions, were attenuated in both Sorsby's fundus dystrophy and X-linked retinoschisis--with some effect on implicit time being noted in the latter condition--but in the unknown group the effect was less demonstrable, only 50% having attenuated flash electroretinograms. Pattern electroretinograms were reduced in all three conditions and in almost all cases. The study demonstrates that some so-called macular dystrophies also have widespread abnormalities affecting the peripheral retina. These findings may contribute to a better understanding of the underlying pathophysiologic mechanisms in these rare forms of retinal dysfunction.

Using YPLL in health planning

OBJECTIVE

The measurement of years of potential life lost before age 65 (YPLL) is one of the Health Outcome Indicators defined by the state of Florida to measure progress toward Healthy People 2000 objectives. The authors describe the outcomes of their work with county health agencies to encourage use of the YPLL statistic.

METHODS

Calculations of the 1993 YPLL rates for Florida counties with populations greater than 50,000 and of inter-county variability in YPLL rates were used to train county health agencies in the use of YPLL.

RESULTS

Sixty-eight percent of all years of potential life lost in Florida in 1993 were attributed to 10 causes. While the total YPLL rates ranged from 3500 per 100,000 to 7000 per 100,000 across Florida counties, the leading causes differed substantially across counties. The YPLL measure was found to be useful in helping county health agencies plan programs to reduce premature mortality.

CONCLUSIONS

Federal, state, and county health units can use YPLL rates to help guide activities toward Healthy People 2000 and to help identify new health problems that require forming new community alliances, but staff members must be trained to use the YPLL statistic appropriately. Causes that vary little across counties enable the implementation of statewide prevention approaches while causes that differ greatly by county will require locally designed interventions.

Outbreak of sporotrichosis among tree nursery workers

In spring 1994, an outbreak of sporotrichosis occurred at a tree nursery in Florida; 9 (14%) of 65 workers involved in production of sphagnum moss topiaries developed lymphocutaneous sporotrichosis. A cohort study of all 65 employees was conducted to identify risk factors for sporotrichosis, and an environmental investigation was done. The risk of sporotrichosis increased significantly with the duration of working with sphagnum moss (P < .05), in particular with filling topiaries (P < .05), and with having less gardening experience (P < .05). Wearing gloves was protective (P < .005). Sporothrix schenckii was cultured from patients and sphagnum moss used in topiary production. Use of restriction fragment length polymorphism revealed an identical pattern for patient isolates that was different from the patterns of environmental isolates. Physicians should be aware of sporotrichosis in patients with ulcerative skin lesions who have a history of occupational or recreational exposure to sphagnum moss.

Allelic imbalance and microsatellite instability in resected Duke's D colorectal cancer

Hepatic resection is the treatment of choice for selected patients with liver metastases from colorectal cancer (CRC). Although the 5-year survival rate among patients after liver resection is 25-45%, 55-75% of patients die from progressive disease. The purpose of this study was to characterize molecular genetic alterations, including microsatellite instability and allelic imbalance, in patients with potentially curative resected liver metastases from CRC and to correlate these molecular features with clinical and pathologic characteristics. We examined DNA from formalin-fixed, paraffin-embedded archival tumor specimens from 141 surgically resected hepatic metastases from CRC. We used microsatellite markers localized to chromosome arms 5q, 8p, 10q, 15q, 17p, 18p, and 18q in a polymerase chain reaction-based assay. Allelic imbalance at each locus and the presence of tumor microsatellite instability were correlated with clinicopathologic features of the tumor and clinical course of the patient. Microsatellite instability at multiple loci was seen in only 2.5% of resected liver metastases, a frequency significantly lower than that previously detected for primary CRC. Additionally, these findings had no significant correlation with disease-free survival or overall survival. Allelic imbalance at one or more loci was seen in 87% of informative tumors. Allelic imbalance on chromosome 17p was seen in 84% of informative tumors, and its presence was associated with a significantly poor disease-free survival (p = 0.015) and overall survival (p = 0.05). These data suggest that allelic imbalance on chromosome 17p is an independent prognostic parameter in patients with potentially curative resected liver metastases from CRC. Such alterations could provide a useful stratification criterion for adjuvant therapy for patients who have undergone curative resection of liver metastases from CRC.

Failure of cooking to prevent shellfish-associated viral gastroenteritis

BACKGROUND

In January 1995, Florida experienced the largest outbreak of oyster-associated gastroenteritis ever reported.

METHODS

We interviewed both the cohort of persons from 38 gatherings where illness was reported and a sample of harvesters and harvest-area residents. Oysters were traced by means of tags and dealer records, and water quality measures in harvest areas were reviewed. We examined stool specimens for small round structured viruses by means of electron microscopy and amplification of RNA by reverse-transcriptase polymerase chain reaction. We also tested serum specimens for antibodies to Norwalk virus.

RESULTS

Of 223 oyster eaters, 58% (129/223) became ill, compared with 3% (2/76) of non-oyster eaters (relative risk, 22; 95% confidence interval, 5.6-87.0). Most oyster eaters (67% [149/223]) ate only cooked (grilled, stewed, or fried) oysters. Oyster eaters who reported eating only thoroughly cooked oysters were as likely to become ill as those who ate raw oysters (relative risk, 0.68; 95% confidence interval, 0.45-1.0; P = .1). In 29 clusters, implicated oysters were from Apalachicola Bay, Florida. A community outbreak occurred in 2 bayside communities before the oyster harvest, leading to an increase in the reportedly common practice of overboard dumping of feces. Small round structured viruses were identified in the stool specimens of 2 harvest-area residents and 9 persons from 8 clusters. Results of water quality tests for fecal coliforms were within acceptable limits.

CONCLUSIONS

This large outbreak of gastroenteritis associated with oysters may have resulted from overboard dumping of feces during a community outbreak of diarrheal illness. Our findings of acceptable water quality measures for fecal contamination and the lack of appreciable protective effect from cooking leave the consumer with no assurance of safety.

Effect of sodium bisulfate on ammonia concentration, fly population, and manure pH in a horse barn

OBJECTIVE

To evaluate the effectiveness of altering the pH of manure with sodium bisulfate, thereby decreasing ammonia concentration and fly population in a horse barn environment.

ANIMALS

4 mixed-breed pony stallions.

PROCEDURE

The 4-week study was scheduled with 2 weeks of treatment (with 2 application rates) and 2 weeks with no treatment (control weeks). During treatment weeks, sodium bisulfate was applied daily to the top of the bedding and straw, then spread on top. Ponies were kept in the stalls 24 hours a day during the 7-day test period and stall cleaning was not done. On day 7 of each week, ammonia concentration, manure pH, number of flies on a fly tape, and fly-evasive behavior patterns were determined.

RESULTS

Sodium bisulfate applied to the horse stall environment daily of either 2.3 or 4.5 kg/9.3 m2 (5 or 10lb/ 100 ft2) decreased ammonia concentration, manure pH, and number of flies in the stall environment, compared with a control period with no sodium bisulfate. Fly-evasive behavior patterns of ponies occupying the stalls, including tail swishes, head tosses, and kicks/strikes, were decreased during the period of sodium bisulfate application.

CONCLUSION

Sodium bisulfate may be an effective method of decreasing ammonia concentration and may serve as a method of fly control in horse barns.

Tumor necrosis factor-alpha allelic frequency and chromosome 6 allelic imbalance in patients with colorectal cancer

The human tumor necrosis factor (TNF) locus is located on chromosome 6p21.3 and contains at least five polymorphic microsatellites. In this study, we compared the allelic frequencies derived from 50 normal controls to 64 patients with colorectal cancer at one of these loci, TNF alpha. No differences in allelic frequencies were observed between these two groups (P = 0.47). However, sequencing of the TNF alpha PCR product revealed two populations of TNF alpha alleles; alleles with the expected DNA sequence (i.e., the expected number of AC/GT repeats) and alleles that contained 8-bp deletions adjacent to the microsatellite repeat. In addition, we also examined paired normal and tumor DNA from the colorectal cancer group for microsatellite alterations at the TNF alpha locus, including allelic loss of heterozygosity and microsatellite instability. Of the 64 tumors examined, 13 (20%) demonstrated microsatellite instability, and 14 (42%) of 33 informative cases demonstrated allelic imbalance. Analysis of 10 additional chromosome 6 loci for allelic loss showed that 23 (47%) of 49 informative cases exhibited allelic imbalance with at least one chromosome 6p marker, 23 (47%) of 49 with at least one 6q marker, and 29 (59%) of 49 with at least one marker on chromosome 6. Examination of tumors for the minimal region of deletion overlap suggests the presence of tumor suppressor genes on both 6p and 6q.

Evaluation of long-term community recovery from Hurricane Andrew: sources of assistance received by population sub-groups

Two three-stage cluster surveys were conducted in South Dade County, Florida, 14 months apart, to assess recovery following Hurricane Andrew. Response rates were 75 per cent and 84 per cent. Sources of assistance used in recovery from Hurricane Andrew differed according to race, per capita income, ethnicity, and education. Reports of improved living situation post-hurricane were not associated with receiving relief assistance, but reports of a worse situation were associated with loss of income, being exploited, or job loss. The number of households reporting problems with crime and community violence doubled between the two surveys. Disaster relief efforts had less impact on subjective long-term recovery than did job or income loss or housing repair difficulties. Existing sources of assistance were used more often than specific post-hurricane relief resources. The demographic make-up of a community may determine which are the most effective means to inform them after a disaster and what sources of assistance may be useful.

Long-term effects of Hurricane Andrew: revisiting mental health indicators

Two population-based surveys of South Dade County, Florida, were conducted after Hurricane Andrew to compare hurricane-related symptoms of mental distress and describe the impact of mental health outreach teams. Households were selected by three-stage cluster sampling and findings from the two surveys, 13 months apart, were compared. Response rates were 75 per cent and 84 per cent. The prevalence of symptoms of mental distress decreased over time. However, in the households contacted by the teams (25 per cent of sample), the prevalence of symptoms (50 per cent) did not differ from households not contacted (43 per cent). Households contacted by teams that reported symptoms were just as likely to have been referred for help by the teams (72 per cent) as those without symptoms (68 per cent). Households reporting symptoms were equally likely to get counselling regardless of whether the teams visited. Mental health teams had no significant impact on mental health symptoms or the use of mental health services. Alternative approaches to mental health outreach teams need to be explored.

Assessing and planning home-based care for persons with AIDS

The HIV/AIDS pandemic continues to gather momentum in many developing countries, increasing the already heavy burden on health care facilities. As a result, donors, implementing partners and communities are beginning to create home-based care programmes to provide care for persons with HIV/AIDS. This paper recommends reorienting this home care provision as a service founded in, and coming from, the community rather than the health system. A methodology, in the form of an assessment matrix, is provided to facilitate the assessment of a community's capacity to provide care for people with AIDS. The focus is on rapid assessment methods using, where possible, readily available information to clearly and systematically define current circumstances. The matrix created for a specific community is then used in the development of an action plan with interventions prioritized and tailored to local needs. A case study from a hypothetical developing country, where HIV/AIDS is a significant problem, is used to illustrate the process.

Modulation of matrilysin levels in colon carcinoma cell lines affects tumorigenicity in vivo

The expression of the metalloproteinase matrilysin in the human colon carcinoma cell lines SW480 and SW620 correlates with the ability of the SW620 cells to invade an artificial basement membrane in vitro and metastasize to the liver following injection into the cecum of nude mice in vivo. Transfection of either wild-type or activated forms of matrilysin into the SW480 cells, which do not express endogenous matrilysin, did not reproducibly increase in vitro invasion but increased the tumorigenicity of the cells when injected into the cecum of nude mice. Antisense reduction of matrilysin levels decreased the tumorigenicity of the SW620 cells and subsequent metastasis to the liver. These results suggest that matrilysin gene expression by colon adenocarcinoma cells is not sufficient for tumor invasion and metastasis but contributes to the tumorigenicity and progression of colorectal tumors.

A switch from stromal to tumor cell expression of stromelysin-1 mRNA associated with the conversion of squamous to spindle carcinomas during mouse skin tumor progression

We previously reported that the expression of stromelysin-1 (ST-1), a matrix-degrading metalloproteinase, correlates with tumor progression in the mouse skin model of carcinogenesis. Using in situ hybridization techniques, we confirmed in this study the expression of ST-1 mRNA in mouse skin keratinocytes treated with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate and also observed dramatic expression of ST-1 message in underlying fibroblastic cells. Benign tumors formed by an initiation/promotion protocol expressed low levels of ST-1 mRNA, which was localized exclusively to stromal tissue surrounding the tumor cells. Squamous cell carcinomas, produced either by chemical carcinogenesis or by injection of cultured cells derived from chemically initiated squamous cell tumors, expressed high levels of ST-1 mRNA, which was also localized to adjacent stromal tissues. In contrast, aggressive, highly metastatic spindle cell tumors expressed ST-1 mRNA in the tumor cells as well as in normal, adjacent stroma. These results suggest that the change from ST-1 expression in surrounding stromal cells to its expression in the tumor cells themselves is associated with the conversion of squamous to spindle carcinomas and may play a causal role in the ability of these cells to invade and metastasize.

Structure and expression of the human gene for the matrix metalloproteinase matrilysin

Matrilysin, a member of the matrix metalloproteinase family, is structurally different from the other matrix metalloproteinases by virtue of the absence of a conserved COOH-terminal protein domain. In addition, matrilysin mRNA is regulated in a specific and distinct manner in normal and malignant tissues. Analysis of the genomic structure of the human matrilysin gene revealed that the organization of the first five exons is highly conserved among the different members of the matrix metalloproteinase family, but that matrilysin contains an atypical sixth exon. The promoter region of the matrilysin gene has several features that are conserved among several other matrix metalloproteinase family members, including the presence of TATA, AP-1, and PEA3 elements. Comparison of the expression of the human matrilysin promoter with rat stromelysin promoter/chloramphenicol acetyltransferase constructs in HeLa cells revealed that constructs containing AP-1 and PEA3 elements respond similarly to epidermal growth factor and tumor promoter (12-O-tetradecanoyl-phorbol-13-acetate) induction, but that the addition of upstream stromelysin sequences results in an increased transcriptional activity not observed with upstream matrilysin sequences. The similarities and differences observed between the promoters of matrilysin and the other metalloproteinases may provide insights into the molecular mechanisms that regulate the expression of this family of enzymes as a whole and the factors that distinguish the expression patterns of individual family members.

Role of matrix metalloproteinases in invasion and metastasis: biology, diagnosis and inhibitors

The processes of tumour invasion and subsequent metastasis are the most lethal aspects of cancer. Whilst many factors are involved, the matrix metalloproteinases (MMPs) have been implicated as key-rate limiting enzymes in the invasive process. This family consisting of eight members of similar structure, can be roughly divided into three groups based on substrate specificity. All are secreted in a latent form and require proteolytic cleavage for activation. The expression of these enzymes is regulated at the transcriptional level by a variety of growth factors and oncogenes. They are also regulated at the protein level by a family of specific inhibitors called the tissue inhibitors of metalloproteinases (TIMPs). Studies in human tumour samples have shown a positive correlation between metalloproteinase expression and metastatic potential. The levels of metalloproteinase expression have been manipulated using molecular biology techniques in several cell lines and shown a similar correlation. These results suggest that an understanding of metalloproteinase expression and proteolytic activity may lead to the development of effective therapeutic agents with the potential to reduce the incidence of metastatic cancer.

The matrix metalloprotease matrilysin (PUMP) is expressed in developing human mononuclear phagocytes

Matrilysin (PUMP, MMP-7) is a member of the metalloprotease gene family, whose constituents are responsible for the remodeling of extracellular matrix. The matrilysin protein is a 28-kDa zymogen possessing catalytic activities against a broad range of extracellular matrix substrates including proteoglycans, gelatin, fibronectin, laminin, and elastin. To gain insights into the biological expression of matrilysin in human cell types, we generated a monospecific, polyclonal antibody against a 16-amino acid sequence derived from its catalytic domain, a region which lacked significant homology with other matrix metalloenzymes. We found this antibody capable of precipitating a 28-kDa protein from the conditioned media of human bone marrow-derived promonocytes and human peripheral blood monocytes cultivated in vitro. Promonocyte matrilysin was rapidly converted to a 19-kDa form by organomercurial activation. While matrilysin was constitutively synthesized by bone marrow-derived promonocytes, its secretion was markedly up-regulated by the mononuclear phagocyte activator, lipopolysaccharide. Furthermore, despite its expression in monocyte precursors, blood monocytes, and monocyte-derived macrophages, matrilysin was not synthesized by human alveolar macrophages under any tested condition. In situ hybridization studies with matrilysin cRNA confirmed the presence of specific mRNA in both human promonocytes and monocytes. Moreover, a marked increase in hybridizable mRNA was observed with lipopolysaccharide treatment suggesting that matrilysin synthesis is pretranslationally regulated. In summary, this represents the first report documenting constitutive and regulated synthesis of matrilysin by a normal human cell type and suggests that matrilysin is expressed as a significant secreted product of mononuclear phagocytes at an intermediate stage of cellular differentiation.

The role of the matrix metalloproteinase stromelysin in the progression of squamous cell carcinomas

The expression of the metalloproteinase stromelysin correlates with the progression of chemically induced squamous cell carcinomas. We demonstrate that the expression of activated stromelysin in papilloma-derived cells enhances in vitro cell invasion. We also demonstrate that the Ha-ras oncogene induces the transcription of the stromelysin gene through an AP-1 dependent pathway. The hypothesis is that alterations in oncogenes and suppressor genes influence stromelysin expression and thus influence subsequent steps of tumor invasion and metastasis.

Expression and localization of the matrix metalloproteinase pump-1 (MMP-7) in human gastric and colon carcinomas

The expression of members of the family of matrix-degrading metalloproteinases (MMPs) is believed to contribute to the complex process of invasion and metastasis. In this study, specific cDNA probes for three members of the stromelysin subfamily of MMPs--stromelysin (MMP-3), stromelysin-2 (MMP-10), and pump-1 (MMP-7)--were used to examine the expression of these three different MMPs in human gastric and colonic carcinomas and in adjacent normal mucosa. The expression of pump-1 mRNA in malignant colon and stomach samples was striking. In a total of 10 gastric carcinoma samples examined, eight (80%) expressed pump-1 transcripts; similarly, 6 of 8 (75%) colon carcinoma samples were also positive. Stromelysin and stromelysin-2 mRNAs were not detected in any of these samples. Expression of the MMPs examined was not detected in any of the adjacent, grossly normal tissue samples. Using in situ hybridization and affinity purified anti-pump-1 antibodies, the expression of pump-1 mRNA and protein was localized to tumor cells and was not detected in stromal or lymphocytic cells. This data suggests that the inappropriate expression of pump-1 by malignant cells may contribute to the neoplastic phenotype.