Responses of benthic invertebrates to combined toxicant and food input in floodplain lake sediments

Benthic communities in floodplain lake ecosystems are often exposed to varying levels of both food and toxicants. Inhibition through toxicants of sensitive species and stimulation through increased amounts of food of opportunistic species have been observed in separate studies. The aim of this study was therefore to assess the responses of benthic invertebrates to combined food and contamination input. Hence, seven floodplain lakes located along the River Waal, The Netherlands, with different levels of food (being either phytoplankton or macrophyte dominated) and toxicants were selected. The responses of the sensitive mayfly Ephoron virgo and the opportunistic midge Chironomus riparius to these sediments were assessed in 10-d growth bioassays with both species and a 28-d emergence experiment with C. riparius. A decrease in both survival and growth of E. virgo was observed with increasing contaminant levels. In contrast, C. riparius responded to the food quantity and quality in the sediments in spite of the toxicants present. Therefore, we conclude that the midge C. riparius is not a suitable test organism for the assessment of sediment toxicity. Alternatively, it proved to be an appropriate test organism to determine the nutritional value of sediments. The mayfly E. virgo turned out to be a much more appropriate test organism for sediment toxicity bioassays because it responds to the toxicant levels in the sediments rather than to the nutritional value. Our results demonstrate that the trophic state of an ecosystem (macrophyte or plankton dominated) influences the ecological risk of toxicants to benthic invertebrates in a species-specific way. It is concluded that not the toxicant load but the combination of food and contaminants determines the persistence of benthic invertebrates and therewith the benthic invertebrate composition in complexly polluted ecosystems.     

Forced vergence fixation disparity parameters with and without a central fusion lock

The effect of a central fusion lock on forced vergence fixation disparity curve parameters, that is, magnitudes of fixation disparity and associated phoria, curve type and the central slope of the curve, was studied in 84 subjects because of ambiguity in the previous studies. It was found that the magnitudes of exo fixation disparity and exo associated phoria decreased significantly when they were measured with the central fusion lock. The central lock had no noticeable effect on the type of the curve, although, the central slope of the curve was flatter in the presence of the central lock.     

Transient synovitis of the hip in children: role of US

Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies.     

Yersinia-related Arthritis in the United Kingdom. A Report of 12 Cases and review of the Literature

Reactive arthritis following infection with Yersinia is endemicin Scandanavian countries; the prevalence is low in the UK,however. We have reviewed the literature pertaining to Yersinia-relatedreactive arthritis in the UK and describe 12 patients who presentedover a 3-year period with an asymmetrical seronegative polyarthropathyand serological evidence of recent Yersinia infection. Fivepatients recalled having a diarrhoeal illness prior to the onsetof the arthropathy. None had a prior history of psoriasis, inflammatorybowel disease or ankylosing spondylitis. A history of urethraldischarge was elicited from one patient. Extra-articular manifestationswere seen in three patients (iritis in two, erythema nodosumin another). Four patients developed chronic joint disease afterperiods of 4, 6, 8, and 18 months, respectively. The prevalenceof Yersinia-related arthritis in the UK may be higher than previouslythought.     

Change in neoadjuvant chemotherapy could alter the prognosis of patients with pancreatic adenocarcinoma: A case report

BACKGROUNDNeoadjuvant treatment has become a standard of care for borderline or locally advanced pancreatic cancer and is increasingly considered even for up-front resectable disease. The aim of this article is to present the case of a 62-year-old patient with locally advanced pancreatic adenocarcinoma who was successfully treated with gemcitabine plus nab-paclitaxel after the failure of the first line treatment.CASE SUMMARYComputerized tomography scan and magnetic resonance imaging demonstrated a nodular lesion of ill-defined limits in the body of the pancreas, measuring approximately 4.2 cm × 2.7 cm, with an infiltrative aspect. The tumor had contact with the superior mesenteric vein, splenomesenteric junction and the proximal segment of the splenic artery, causing focal reduction of its lumens. Due to vascular involvement, neoadjuvant chemotherapy treatment with eight cycles of “folinic acid, 5-fluorouracil, irinotecan and oxaliplatine” (FOLFIRINOX) were performed. At the end of the cycles, surgery was performed, but the procedure was interrupted due to finding of lesions suspected of metastasis. Gemcitabine plus nab-paclitaxel was then successfully used for neoadjuvant treatment with subsequent R0 surgical resection.CONCLUSIONGemcitabine plus nab-paclitaxel may be effective as an alternative regimen when FOLFIRINOX fails as the first line of treatment, suggesting the need for further studies to identify which patients would benefit from each type of therapeutic approach.     

Detection of antibodies to Trypanosoma cruzi among blood donors in the southwestern and western United States. II. Evaluation of a supplemental enzyme immunoassay and radioimmunoprecipitation assay for confirmation of seroreactivity

BACKGROUND: Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi, is endemic to Latin America and may be transmitted in the United States via blood donated by infected immigrants. Blood- borne pathogens such as T. cruzi require supplemental testing for confirmation of seroreactivity. STUDY DESIGN AND METHODS: A study was undertaken to determine an optimal scheme for confirmation of seroreactivity in repeatedly reactive samples identified by the Chagas antibody enzyme immunoassay (EIA). The procedure for initial confirmation involves three purified antigens coated onto three separate polystyrene beads and uses an EIA format. If the sample is reactive with two of three or three of three antigens, it is confirmed as seroreactive. If none or one of three beads is reactive, the sample is indeterminate and subjected to a radioimmunoprecipitation assay (RIPA). The RIPA must demonstrate characteristic bands at 32, 34, and 90 kDa. RESULTS: When tested with sera from persons with potentially cross-reactive diseases (n = 39) or against a presumed negative population from southeast Wisconsin (n = 289), the confirmatory EIA had a specificity of 100 percent. Sensitivity was 100 percent (28/28) with xenodiagnosis-positive sera and 97.6 percent (80/82) with chagasic sera from Latin America. The RIPA showed a specificity of 100 percent in EIA- nonreactive samples (n = 100) and a sensitivity of 100 percent with both xenodiagnosis-positive (28/28) and chagasic (82/82) sera. CONCLUSION: The confirmatory EIA and the RIPA together provide a highly specific and sensitive means of confirming seroreactivity for antibodies to T. cruzi.     

Validation of MCADD newborn screening

Medium‐chain acyl‐CoA dehydrogenase deficiency (MCADD) represents a potentially fatal fatty acid β‐oxidation disorder. Newborn screening (NBS) by tandem mass spectrometry (MS/MS) has been implemented worldwide, but is associated with unresolved questions regarding population heterogeneity, burden on healthy carriers, cut‐off policies, false‐positive and negative rates. In a retrospective case‐control study, 333 NBS samples showing borderline acylcarnitine patterns but not reaching recall criteria were genotyped for the two most common mutations (c.985A>G/c.199C>T) and compared with genotypes and acylcarnitines of 333 controls, 68 false‐positives, and 34 patients. c.985A>G was more frequently identified in the study group and false‐positives compared to controls (1:4.3/1:2.3 vs. 1:42), whereas c.199C>T was found more frequently only within the false‐positives (1:23). Biochemical criteria were devised to differentiate homozygous (c.985A>G), compound heterozygous (c.985A>G/c.199C>T), and heterozygous individuals. Four false‐negatives were identified because our initial algorithm required an elevation of octanoylcarnitine (C₈) and three secondary markers in the initial and follow‐up sample. The new approach allowed a reduction of false‐positives (by defining high cut‐offs: 1.4 μmol/l for C₈; 7 for C₈/C₁₂) and false‐negatives (by sequencing the ACADM gene of few suspicious samples). Our validation strategy is able to differentiate healthy carriers from patients doubling the positive predictive value (42→88%) and to target NBS to MCADD‐subsets with potentially higher risk of adverse outcome. It remains controversial, if NBS programs should aim at identifying all subsets of all diseases included. Because the natural course of milder variants cannot be assessed by observational studies, our strategy could serve as a general model for evaluation of MS/MS‐based NBS.     

Italian healthcare workers' views on mandatory vaccination

Background  

Mandatory vaccination has contributed to the success of immunisation programmes but voluntary vaccination allows people to be responsible for their own health. There are benefits from both policies and the arguments between them remain subject to debate within and without the scientific community, both nationally and internationally. The aim of this study is to assess the opinions of those who actually work in the Vaccination Service.     

Mineral balance and whole body bone mineral content in very low-birth-weight infants

Fat and mineral metabolic balance studies were performed in 25 normal very low-birth-weight infants ( 1500 g at birth) fed either pooled pasteurized human milk supplemented with calcium, phosphorus and magnesium, or a preterm formula. Calcium, phosphorus and magnesium intake were similar in both groups and averaged 100mg/kg/day, 72 mg/kg/day and 8 mg/kg/day, respectively. Calcium and phosphorus retention was higher in the subjects fed fortified human milk than in those receiving a preterm formula (65±14 and 62±9mg/kg/day versus 55±12 and 47±7mg/kg/day respectively). The difference was only significant for phosphorus. Magnesium retention was similar in the two groups and averaged 3 mg/kg/day. Fat intake and absorption was significantly higher in the preterm formula fed group than in the one fed fortified human milk (5.5±0.4 g/kg/day and 88±4% versus 4.2±1 g/kg/day, 79±6% respectively). Assessment of the whole body bone mineral content by dual energy X-ray absorptiometry was performed at 3 and 6 months of age in another group of 25 low-birth-weight infants fed either fortified human milk or a preterm formula. Whole body bone mineral content (BMCt) was low (43.3±30.8 g of hydroxyapatite) at 3 months of age (theoretical term) compared to normal full-term newborns at birth. There was no significant influence of the diet. At 6 months of age, BMCt reached 168.6±36.6g, a value similar to that of full-term newborns, with no significant difference between the two regimen groups. The deficit in the 12 subjects who had a BMCt under 30 g at 3 months of age had been corrected at age 6 months. Premature babies fed a pooled pasteurized human milk enriched with calcium, phosphorus and magnesium favored a better retention of calcium and phosphorus. However, no significant influence of the two diets studied was observed on the gain in BMCt over the first 6 months of life.