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PubMed1989

Holographic interferometry.

Since its inception three decades ago, holographic interferometry has proven to be a powerful nondestructive testing technique for the measurement of displacement and its derivatives. It is a whole-field, noncontact method which requires the use of a hologram to record three-dimensional information about the surface of an object. After a stress is applied to the object, its new surface geometry is compared with the previously recorded state. Changes of the surface of the object, which are manifest as a series of interference fringes superimposed on the image of the object, can be observed statically or in real time to reveal the displacement. Current state-of-the-art techniques such as heterodyne and digital phase shifting interferometry, which have extended the resolution of holographic interferometry far beyond fringe counting, are reviewed. Particular emphasis is placed upon applications in biomedical engineering and medicine, although potentially applicable techniques from other disciplines are examined. The paper is broken into two main parts. In the first part, the scope and potential limitations of this branch of metrology are presented. In the second part, a review of applications in biomedical engineering is presented. The references cited in the first section are the seminal papers in the field. The applications section, which relies upon the results of the first section, presents a critical review of the literature by analyzing the results of a few representative studies.

Fiber Optic Technology↗

PubMed1989

M-mode ultrasonic detection of microbubbles following saturation diving: a case report and proposal for a new grading system.

An M-mode ultrasound system was used to obtain a reliable method for the evaluation of microbubbles caused by decompression. When the probe is focused in the outflow tract of the right ventricle it is easy to recognize a linear configuration of the echoes caused by the microbubbles. A quantitative study of microbubbles can be done by counting the number of linear echoes per second. Application of this method is reported following saturation diving decompression. We think the reported method is worthy of further use.

Decompression↗

PubMed1996

[Experimental study on in vivo hematopoietic regulation of IL-6 gene-transfected tumor vaccine].

In the present study, we investigated the effects on hematopoiesis of inactivated vaccines prepared from mouse erythroid leukemia cells (FBL-3) transfected with IL-6 gene. After treatment with IL-6 gene-transfected FBL-3 cells, the platelet count in mice started to increase at day 4, reached its maximum at day 10 and lasted for 25 days. The neutrophil count also increased significantly, but WBC count remained unchanged. The CFU-GM and CFU-MK were elevated to some extent in bone marrow and spleen. These results indicated that in addition to augmentation of antitumor immunity, IL-6 gene-transfected tumor vaccine could promote hematopoietic functions in bone marrow and spleen, and elevate platelet and neutrophil counts in peripheral blood. This approach to gene therapy may be applicable in leukemia treatment, especially for thrombocytopenia related to leukemia or chemotherapy.

Animals↗

PubMed2004

Comparison of fluorescence microscopy and solid-phase cytometry methods for counting bacteria in water.

Total direct counts of bacterial abundance are central in assessing the biomass and bacteriological quality of water in ecological and industrial applications. Several factors have been identified that contribute to the variability in bacterial abundance counts when using fluorescent microscopy, the most significant of which is retaining an adequate number of cells per filter to ensure an acceptable level of statistical confidence in the resulting data. Previous studies that have assessed the components of total-direct-count methods that contribute to this variance have attempted to maintain a bacterial cell abundance value per filter of approximately 10(6) cells filter(-1). In this study we have established the lower limit for the number of bacterial cells per filter at which the statistical reliability of the abundance estimate is no longer acceptable. Our results indicate that when the numbers of bacterial cells per filter were progressively reduced below 10(5), the microscopic methods increasingly overestimated the true bacterial abundance (range, 15.0 to 99.3%). The solid-phase cytometer only slightly overestimated the true bacterial abundances and was more consistent over the same range of bacterial abundances per filter (range, 8.9 to 12.5%). The solid-phase cytometer method for conducting total direct counts of bacteria was less biased and performed significantly better than any of the microscope methods. It was also found that microscopic count data from counting 5 fields on three separate filters were statistically equivalent to data from counting 20 fields on a single filter.

Biomass↗

PubMed1984

Inhibition of platelet production induced by an antiplatelet drug, anagrelide, in normal volunteers.

Administration of anagrelide, an antiplatelet agent, to ten normal male subjects was accompanied by an asymptomatic fall in platelet count. The drop was gradual and usually occurred within two weeks. Only a slight shortening of platelet survival was seen. Bone marrow morphology appeared normal. Measurement of platelet production rates showed a reduced response to thrombocytopenia. A substantial increase in the percentage of large platelets was observed in drug treated subjects. These observations are compatible with a selective inhibition of platelet production. Based upon these findings, the use of anagrelide will probably be best limited to short-term applications or to conditions where selective lowering of platelet count may be desired such as in polycythemia rubra vera or idiopathic thrombocytosis.

Blood Platelets↗

PubMed2006

Enterococcus faecium EK13--an enterocin a-producing strain with probiotic character and its effect in piglets.

The experiment was conducted to determine the effects of the inoculation of the probiotic and enterocin A-producing strain Enterococcus faecium EK13 on selected parameters of metabolic profile, gut microflora, growth, and health in newborn piglets of Slovak White Improved. Piglets for study were divided into two groups: one group (EK13 group, n=8) received strain EK13 per os once daily for 7 days (2ml per piglet, 10(9)CFU/mL of saline buffer). The control group of piglets (n=7) was given placebo-saline buffer. The experiment lasted 14 days. After 7 days, strain EK13 reached 9.8 log(10) CFU/g in faeces of E. faecium EK13 treated piglets while counts of Escherichia coli were significantly lower (P<0.01) than in piglets of the control group. The concentrations of total serum protein, calcium, haemoglobin, haematocrit, red blood cell count and index of phagocytic activity of leukocytes were significantly higher after application of strain EK13. On the other hand, cholesterol was significantly lower in the EK13 group of animals. On day 14, piglets were killed and samples of intestinal contents were taken. Total counts of bacteria in the intestinal contents (jejunum, ileum, caecum, colon) were not significantly influenced. The pH value was significantly lower (P<0.05) only in duodenum of piglets receiving E. faecium EK13. There was a significant higher concentration of lactic acid (P<0.01) and propionic acid in the colon (P<0.001) of the EK13 group. Application of E. faecium EK13 did not influence the daily body weight gain significantly.

Animals↗

PubMed1996

Target value tailored (TVT) apheresis approach for blood progenitor cell collection after high-dose chemotherapy and rh-G-CSF.

Twenty-eight patients with different hematological diseases (17 non-Hodgkin's lymphoma, one Hodgkin's disease and 10 multiple myeloma) underwent peripheral blood progenitor cell (PBPC) collection after cyclophosphamide 7 g/m2 and rh-G-CSF. Fifty-eight leukaphereses were carried out with a fully automated PBPC collection procedure. Progenitor cell release was monitored by standardized determination of CD34+ cells in the peripheral blood. After a profound aplasia, a continuous increase in CD34+ cells in the peripheral blood was seen for at least 3-4 days. In 82% of our patients more than 2.5 x 10(6) CD34/kg could be collected using a standard apheresis of 10 l. There was a high correlation between the CD34+ cells in the peripheral blood and CD34+ cells/kg harvested. (r2 = 0.91). A relatively constant ratio (median 14.3, range 3.2-22.6) was found between CD34+ cells/kg and CFU-GM/kg. Based on the CD34 values of the pre-apheresis blood and the body weight of an individual patient and using the mathematical model of regression analysis (y = mx + b) for the correlation between the CD34+ cells/microliter in the pre-apheresis blood and the CD34+ cells/kg, it was possible to create a formula allowing for target value tailored apheresis. Using this formula, the blood volume which needs to be processed in order to harvest a desired number of CD34+ cells/kg can be calculated. This strategy can be applied to reduce the time for and the number of aphereses. Nineteen leukaphereses were carried out applying the formula. In 18 of 19 leukaphereses the expected CD34+/kg values were correctly achieved or exceeded. The formula was most reliable when the CD34 value was higher than 15/microliter and when the WBC count was below 20 x 10(9)/l in the pre-apheresis blood. For mobilizations using hematopoietic growth factors alone our formula is not applicable, because in most cases the pre-apheresis white blood cell count is higher than 20 x 10(9)/l and the collection efficacy of lymphomonocytoid cells decreases with a high pre-apheresis white blood cell count. The formula also works with other mobilization regimens that induce a pronounced aplasia.

Antigens, CD34↗

PubMed2006

[Bacterial contamination in an egg-breaking factory and its control].

From January to November, 2003, bacterial contamination was surveyed in a small egg-breaking factory that produced non pasteurized liquid egg. Test egg samples were taken at various stages of the egg processing operation. Salmonella Enteritidis was isolated from liquid egg yolk and liquid egg white on October, but was not found in any other samples (50 liquid egg samples, 21 containers and 94 attached production facilities and gloves). The data suggest that the contamination rate (3.8%) is lower than those reported previously. Levels of bacterial standard plate counts, gram-positive bacterial counts and gram-negative bacterial counts were in the ranges of 2 to 5 log CFU/g, 2 to 3 log CFU/g, 2 to 5 log CFU/g, respectively. Liquid egg containers returned from customers was contaminated with bacteria at the level of 8 log CFU per container. However, washing and application of a sanitizer containing sodium hypochlorite reduced the bacterial counts.

Bacteriological Techniques↗

PubMed1985

The automated complete blood cell count. Use of the red blood cell volume distribution width and mean platelet volume in evaluating anemia and thrombocytopenia.

The availability of automated blood cell analyzers that provide an index of red blood cell volume distribution width (RDW) and a mean platelet volume (MPV) has led to new approaches to patients with anemia and thrombocytopenia. The RDW, which measures heterogeneity of the red blood cell population, complements the mean corpuscular volume in the differential diagnosis of anemia based on peripheral blood analysis. The MPV varies inversely but nonlinearly with the platelet count in normal individuals and is of value in assessing platelet production in the thrombocytopenic patient. The clinical applications of the RDW and MPV, which are currently reported on most routine blood cell counts, are discussed.

Anemia↗

PubMed2004

Are alterations of lymphocyte subpopulations in polymicrobial sepsis and DHEA treatment mediated by the tumour necrosis factor (TNF)-alpha receptor (TNF-RI)? A study in TNF-RI (TNF-RI(-/-)) knock-out rodents.

Sepsis is associated with depression of T cell-dependent immune reactivity with proinflammatory cytokines, such as tumour necrosis factor (TNF)-alpha, playing an important role. Recent investigations describe an association between these immunological alterations and disturbances of the endocrine system, related most frequently to sex steroid hormones. Dehydroepiandrosterone (DHEA), one of the most abundant adrenal sex steroid precursors, seems to have a protective immunological effect towards septic insults. In this study, both the role of TNF-receptor I (RI) and possible interactions in the protective role of DHEA were investigated in a murine model of polymicrobial sepsis. Polymicrobial sepsis was induced by caecal ligation and puncture (CLP) in a murine model. The effects of DHEA on survival, clinical parameters and cellular immunity (T lymphocytes and natural killer (NK) cells) were investigated. CLP was performed in genetically modified TNF-RI knock-out (TNF-RI(-/-)) and genetically unmodified (wild-type, WT) mice. DHEA application was associated with a decrease in the mortality rate in WT animals. A mortality rate of 91.7% was observed in TNF-RI(-/-) mice after CLP. This mortality rate was reduced to 37.5% by the application of DHEA. In sham-operated TNF-RI(-/-) animals, a significantly higher proportion of NK cells within the lymphocyte population was measured compared with the corresponding WT group. After CLP, a significant increase in the percentage cell count of NK cells was recorded in WT mice. Overall, following DHEA application in WT mice, an alteration in the cellular immune response was characterized by a reduction in the percentage counts of CD4(+), CD8(+) and NK cells. In the group of TNF-RI(-/-) mice treated with DHEA, no increase in the percentage cell count of NK cells was observed after CLP. No data for cell analysis were available from the CLP-TNF-RI(-/-) mice treated with saline, due to the high mortality rate in these animals. DHEA reduces the complications of sepsis in a TNF-RI-independent manner. Our study suggests that NK cells are involved in the protective mechanism of DHEA in WT mice. It would therefore seem that DHEA represents a feasible alternative therapy for the dysregulated immune system in sepsis.

Animals↗

PubMed1996

Case counting in epidemiology: limitations of methods based on multiple data sources.

BACKGROUND: The application of capture-recapture methods in epidemiology has been proposed as an alternative to field surveys. This methodology is important for the future of epidemiology and deserves a critical analysis. METHODS: This paper reviews conditions for applying the capture-recapture models to epidemiological data, taking into account practical considerations, in particular the problem of case definition. RESULTS: The underlying assumptions are particularly restrictive resulting in a theoretical limitation of their applicability. In spite of the statistical developments designed to overcome these difficulties, the practical conditions for using the existing lists are often not fulfilled (availability, confidentiality). The major restriction is on the quality of the data which are often far below the standards required in specific prevalence surveys and which may differ between lists. This may result in a dramatic lack of specificity. The definition of the virtual subgroup of patients missing in all lists as generated by the statistical procedure, is questionable particularly when counting living patients. Field studies would be necessary for validation. CONCLUSIONS: In some particular situations (e.g. deceased patients, rare diseases), this methodology may provide a useful approximation to the number of ill subjects events, but users should be aware of their poor specificity. It can also be useful to complement data from surveillance systems by careful cross-checking with independent sources of information. Currently, this method cannot, in any way, replace direct population prevalence or incidence surveys.

Epidemiologic Methods↗

PubMed2003

Is pain fatiguing? A structured evidence-based review.

STUDY DESIGN: This is a structured, evidence-based review of all available studies on the coexistence of fatigue and pain. OBJECTIVES: To determine what evidence, if any, exists for or against the existence of an association between fatigue and pain and a potential etiological relationship between pain and fatigue. SUMMARY OF BACKGROUND DATA: Pain physicians have noted fatigue as a frequent complaint in chronic pain patients (CPPs), and previous studies have reported the association of fatigue and pain. METHODS: Computer and manual literature searches for studies relating to fatigue and pain produced 23 reports. These references were reviewed in detail, and information relating to the above problems was abstracted and placed into tabular form. Each report was also categorized for the type of study it represented according to the guidelines developed by the Agency for Health Care Policy and Research (AHCPR). In addition, a list of 15 quality criteria was utilized in order to measure the quality of each study. Each study was categorized for each criterion as positive, (criterion filled), negative (criterion not filled), or not applicable independently by two of the authors. A percent quality score was obtained for each study by counting the total number of positives obtained, dividing by 15 minus the total number of not applicable, and multiplying by 100. Only studies having a quality score of 75% or greater were utilized to formulate the conclusions of this review. The strength and consistency of the evidence represented by the remaining studies was then categorized according to the AHCPR guidelines. Conclusions of this review were based on those results. RESULTS OF DATA SYNTHESIS: Of the 23 reports, 17 had quality scores of 75% or greater. Of these 17 reports, 94.1% indicated that there was an association between fatigue and pain. In addition, 100% of a subgroup of 13 reports (all with quality scores of 75% or greater) indicated that there may be an etiological relationship between pain and fatigue. The overall strength and consistency of this evidence according to AHCPR guidelines was therefore categorized as A (highly consistent findings from multiple studies). CONCLUSIONS: Based on the above results, it was concluded that there is an association between fatigue and pain and that there may be an etiological relationship between pain and fatigue. Pain physicians and other pain treatment professionals should be aware of the high prevalence of fatigue in pain patients. In addition, future research might investigate possible mechanisms for the relationship between pain and fatigue.

Chronic Disease↗

PubMed2003

A structured evidence-based review on the meaning of nonorganic physical signs: Waddell signs.

STUDY DESIGN: This is a structured, evidence-based review of all available studies addressing the concept of nonorganic findings: Waddell signs (WSs). OBJECTIVES: To determine what evidence, if any, exists for the various interpretations for the presence of WSs on physical examination. SUMMARY OF BACKGROUND DATA: WSs are a group of eight physical findings divided into five categories, the presence of which has been alleged at times to have the following interpretations: Malingering/secondary gain, hysteria, psychological distress, magnified presentation, abnormal illness behavior, abnormal pain behavior, and somatic amplification. At the present time, there is, therefore, significant confusion as to what these findings mean. METHODS: A computer and manual literature search produced 61 studies and case series reports relating to WSs. These references were reviewed in detail, sorted, and placed into tabular form according to the following subject areas: 1) Reliability (test-retest); 2) Reliability (inter-rater); 3) Reliability (factor analysis); 4) Validity, psychological distress; 5) Validity, correlation Minnesota Multiphasic Pain Inventory (MMPI); 6) Validity, correlation abnormal illness behavior; 7) Validity, other behaviors; 8) Validity, as a nonorganic phenomenon; 9) Validity, correlation pain drawing; 10) Validity, functional performance; 11) Validity, treatment outcome; 12) Validity, predicting surgical treatment outcome; 13) Validity, return to work outcome; 14) Validity, secondary gain correlation; and 15) Validity, pain correlation. Each study in each topic area was classified according to the type of study it represented according to the type of evidence guidelines developed by the Agency for Health Care Policy and Research (AHCPR). In addition, a list of 14 study quality criteria was used to measure the quality of each study. Each study was categorized for each criterion as positive, (criterion filled), negative (criterion not filled), or not applicable independently by two of the authors. A percent quality score was obtained for each study by counting the total number of positives obtained, dividing by 14 minus the total number of not applicables, and multiplying by 100. Only studies having a quality score of 75% or greater were used to formulate the conclusions of this review. The strength and consistency of the evidence represented by the remaining studies in each topic area (above) was then categorized according to the strength and consistency AHCPR guidelines. Conclusions of this review for each topic area are based on these results. RESULTS OF DATA SYNTHESIS: Of the 61 studies, four had quality scores below 75% and were not used to generate the results of this review. According to the AHCPR guidelines for strength and consistency of the reviewed data, the following results were obtained: 1) There was consistent evidence for WSs being associated with decreased functional performance, poor nonsurgical treatment outcome, and greater levels of pain; 2) There was generally consistent evidence for WSs not being associated with psychological distress, abnormal illness behavior, or secondary gain; 3) There was also generally consistent evidence that WSs are an organic phenomenon and that they cannot be used to discriminate organic from nonorganic problems; 4) There was inconsistent evidence that WSs do demonstrate inter-rater reliability, do not correlate with the neurotic triad of the MMPI, are associated with poorer surgical treatment outcome, and are associated with nonreturn to work; 5) There was little or no evidence that WSs demonstrate test-retest reliability, or reliable factors, and are associated with self-esteem problems, catastrophizing, or the nonorganic pain drawing. CONCLUSIONS: Based on the above results, the following conclusions were made: 1) WSs do not correlate with psychological distress; 2) WSs do not discriminate organic from nonorganic problems; 3) WSs may represent an organic phenomenon; 4) WSs are associated with poorer treatment outcome; 5) WSs are associated with greater pain levels; 6) WSs are not associated with secondary gain; and 7) As a group, WS studies demonstrate some methodological problems.

Acute Disease↗

PubMed2001

Decaying source method for scintillation camera resolving times.

An earlier paper by the author showed that scintillation camera systems can be described effectively using the resolving times T and tau0 of the dominant nonparalyzable and paralyzable components, that is, the detector system and the computer interface, respectively. When used with a full spectrum window, the camera has a lower nonparalyzable and an upper paralyzable operating range with normalized threshold input rate n(t)= N(t)tau(0) = ln(1 +k(T)n(t)), where kT= T/(tau)0. Correct determination of T and tau(0) requires that both r12 and r in the normalized two-source equations kT=(2/r12- 1/r) and k0=(r12/2r2)ln(2r/r12) come from the nonparalyzable (n< or =n(t)) and paralyzable (n> or =n(t)) ranges, respectively. A serious constraint of the two-source method, therefore, is that the large ratio a = n12 ln = 2 can lead to an input rate range (n,n12), which includes the threshold point n,, and in which neither T nor tau0 can be measured correctly. The decaying source method constitutes a refinement of the two-source method, which enables smaller ratios 1<a<2 to be used, and also includes the two-source method as a special case (a=2). This new method requires just two consecutive readings on a single decaying source, as opposed to three measurements on two sources of activity, for each determination of T or tau0, thus also minimizing staff exposure. The fact that only count rates and time intervals need now be recorded greatly simplifies computerization of the data acquisition and analysis activities, and the potential for real-time applications is obvious. The method enables T and tau0 to be measured accurately and with sufficient resolution to reveal possible variations with input rate. Long measurement times using a decaying source can be avoided, if required, by using a set of decaying sources simultaneously to cover different portions of the count rate range. The application of the measurement procedure in real-time and the use of the resolving times in the accurate correction of deadtime losses, also in real-time, are treated separately in another paper.

Gamma Cameras↗

PubMed1997

The importance of three-dimensional brachytherapy treatment planning for nasopharyngeal carcinoma.

High dose rate (HDR) intracavitary brachytherapy is now more frequently incorporated into treatment programmes for patients with persistent and recurrent nasopharyngeal carcinoma (NPC). However, many centres still employ two-dimensional (2-D) image reconstruction for applicators with a three-dimensional (3-D) orientation. In this study, we introduced the use of a mobile modified Nucletron reconstruction box inside the brachytherapy suite for image reconstruction and quality assurance. Three-dimensional reconstruction of the applicators' configurations proved possible and the dose distributions generated by the 2-D and 3-D image reconstructions could be compared. Thirty-one applications were included in this part of the analysis. The results showed that, based on the 2-D planning method, the reference doses were under-prescribed by 1%-10% in all except one patient, whose dose was over-prescribed by 3%. The evaluated doses to the floor of the sphenoid, which was shown to be significant for subsequent local control, was shown to be underestimated by up to 19% or overestimated by 18%, with an average of 5.9% dose underestimation. With this system, the reliability of the anchoring techniques was verified by posttherapy radiographs. Any catheter displacement of more than 1 mm was counted as a failure. Nine of the 43 verified applications were classified as failures, although six of nine catheter displacements measured < or = 2.5 mm. We recommend the routine use of a modified reconstruction box for 3-D image reconstruction for dose calculation and prescription in the treatment of NPC with HDR intracavitary brachytherapy. Quality assurance programmes should be included as an integral part of any HDR treatment; their importance cannot be overemphasized.

Brachytherapy↗

PubMed1990

Natural history of androgenetic alopecia.

Twenty-two men with patterns III-Va androgenetic alopecia were entered into a 10-month study aimed at establishing information on the natural progression of hair loss over a period of time typical of studies of hair growth promoters. The methodology employed was the same as that in published clinical trials of topical minoxidil, but the men refrained from application of either active drug or vehicle to their scalps. As one of the potential explanations for the observed 'placebo-effect' seen in non-vellus hair counts in the topical minoxidil trials was a learning curve of novice hair counters, we were particularly interested in evaluating this in our 'no-treatment' trial. To that end, both a novice (Observer I) and an experienced (Observer II) hair counter independently performed the hair counts. There was a mean decline in the number of vertex target area non-vellus hairs (-17.2 +/- 80.3 for Observer I and -26.6 +/- 63.5 for Observer II) at the end of 10 months; this was not significant. The novice's hair counts were lower than the experienced observer's counts at baseline, and the difference remained relatively constant during the study. Without the application of a placebo, there was no increase in hair growth, making it unlikely that the methods of hair counting led to the 'placebo-effect' seen in prior topical minoxidil studies.

Adult↗

PubMed2002

Evaluation of preventive treatments in low-density gypsy moth populations using pheromone traps.

Pheromone traps can be used for evaluating the success of treatments that are applied to either eradicate or delay the growth of isolated low-density populations of the gypsy moth, Lymantria dispar (L.). We developed an index of treatment success, T, that measures the reduction in moth counts in the block treated adjusted by the change in moth counts in the reference area around it. This index was used to analyze the effectiveness of treatments that were conducted as part of the USDA Forest Service Slow-the-Spread of the gypsy moth project from 1993 to 2001. Out of 556 treatments that were applied during this period, 266 (188,064 ha) were selected for the analysis based on several criteria. They included 173 blocks treated with Bacillus thuringiensis (Berliner) variety kurstaki and 93 blocks treated with racemic disparlure. Analysis using general linear models indicated that disparlure treatments were significantly more effective than B. thuringiensis treatments in reducing moth captures. The frequency of repeated treatments in the same area was higher after B. thuringiensis than after disparlure applications. Treatments were more successful if the pretreatment moth counts outside of the block treated were low compared with moth counts inside the block.

Animals↗

PubMed1997

Assessment of the viability of Schistosoma mansoni schistosomula by comparative uptake of various vital dyes.

Of various vital dyes used to assess schistosomula viability, toluidine blue enabled differential counting of the schistosomula on microscope slides but not in culture wells, whereas methylene blue could be added directly to the schistosomula suspension in culture wells of microtiter plates. Toluidine blue uptake by dead parasites was very fast. It mostly also partially stained damaged but not dead organisms. Its main disadvantage was rapid, nonspecific staining of live schistosomula, requiring prompt counting of a preparation and additional reliance on motility for assessment of viability. Methylene blue staining of dead worms was slower, but it did not stain the live worms until about 1 h after dye application, enabling its addition to a series of preparations for consecutive counting. It did not always stain flattened, dead schistosomula or it stained them an uncontrasting pale blue. This dye remarkably induced movement in seemingly inert and probably damaged worms, thus enabling determination of viability even following poor staining or a lack of staining.

Animals↗