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In this paper we discuss the elastic light scattering techniques used in blood cell counting and classification and expound the principles of elastic light scattering techniques and four theoretical scattering models of blood cell and the applicable areas. Also we analyze their application in recent years and point out the problems to be solved.
In cancer chemotherapy, it is important to design treatment strategies for drug protocols that ensure a desired rate of tumor cell kill without overdosing the host. Mathematical modeling was used for optimization in which we minimize the end value of the tumor cells while limiting toxicity by always maintaining the white blood cell count beyond a limit. The optimal solution for this is a mixture of an initial bolus application of drug followed by no drug and then continuous infusion that keeps the normal cell population at its lower limit while decreasing the tumor cell population.
The response to pelotherapy has been assessed clinically and immunologically basing on T-lymphocyte count. Altogether 124 rheumatoid arthritis (RA) patients were examined. In patients with low baseline levels of T-lymphocytes the effect of pelotherapy appeared inferior to that in patients with normal T-lymphocyte counts. It was suggested that T-cell immunosuppressed RA patients should receive combined therapy with mud applications and anabolic stimulator potassium orotate.
Dinitrochlorobenzene (DNCB) is a simple chemical useful to evaluate both afferent (sensitizing) and efferent (reacting) limbs of the delayed, cell-mediated immune system. This system invokes the small lymphocyte (T cell) and is apparently part of the host defense against cancer. Severnty-two patients with new primary squamous cell carcinomas of the larynx, hypopharynx and oropharynx were sensitized to DNCB by contact application, and delayed cutaneous hypersensitivity tested. The T cells were also assessed in this study by lymphocyte count. All patients were treated for cure. Ninety-one percent of DNCB reactors were alive and tumor-free at two years. Forty-five percent of negative reactors had recurrent tumor and died of carcinoma. Cases grouped by site among glottic, supraglottic and inferior hypopharynx showed identical results. Lymphocyte counts showed a trend in the same direction. On statistical analysis, all differrences were significant. Eighty-five percent of recurrent tumors occurred in patients who were nonresponders. The present data suggest DNCB reactivity is helpful in predicting outcome after surgery, or combined radiation and surgery, for mucosal squamous carcinoma of the head and neck.
Statistical models are used to investigate the need for automation in several potential areas of application of FISH-labelling techniques, including perinatal and tumour cytogenetics, genetic toxicology, and gene mapping. Predictions of the models, based on current estimates of likely error rates for spot-counting and measuring, suggest that a fully automated system is a realistic prospect for detecting full or high-level mosaic trisomies and that interactive systems have the potential to reduce substantially the human workload required to detect residual malignant disease or radiation-induced chromosome aberrations. There appear to be no foreseeable limits to the requirements for speed and accuracy in such systems, since there is effectively no lower limit to the level of relevant biological detail that can be investigated with these techniques.
In the United States (US), the history of bacterial plate counting (BPC) methods used for water can be traced largely through Standard Methods for the Examination of Water and Wastewater (Standard Methods). The bacterial count method has evolved from the original Standard Methods (1st edition, 1905) plate count which used nutrient gelatin and incubation at 20 degrees C for 48 h, to the HPC method options in the latest edition of Standard Methods that provide greater flexibility of application, depending on the data needs of the water analyst. The use of agar-agar as a gelling agent, replacing gelatin, allowed the use of higher incubation temperatures and resulted in the "body temperature count" (37 degrees C) found in the 3rd through the 8th edition of Standard Methods. The change from 37 degrees C incubation to 35+/-0.5 degrees C accommodated laboratories that did both milk and water analyses. By using a single temperature, fewer incubators were needed. The term "standard plate count" (SPC) first appeared in 1960 (11th edition) along with plate count agar. Incubation at 20 degrees C for the plate count was dropped from the 13th to 15th editions and few changes were made in the SPC method from the 11th edition through the 13th editions. Plate count analysis of bottled waters was included in the 14th edition (1975), calling for incubation at 35+/-0.5 degrees C for 72+/-4 h. Perhaps the most significant changes in plate count methods occurred with the 16th edition (1985). The term heterotrophic plate count replaced the standard plate count, and the spread plate (SP) and membrane filter (MF) methods were added along with new media for pour and spread plates (R2A agar and NWRI agar, both low nutrient) and for the membrane filter method (mHPC medium). The use of low nutrient media, lower incubation temperature, and longer incubation times, results in higher plate count results for most water samples. The options currently available, including low and high nutrient media, incubation temperatures (20 degrees C, 28 degrees C or 35 degrees C), plating methods (pour plate (PP), spread plate and membrane filter) and range of incubation times (24, 48, 72 h and 5-7 days) provide great flexibility in the application of the HPC analysis to drinking water.
OBJECTIVE: To describe application of a new method for the evaluation of anti-Trypanosoma cruzi activity against intracellular forms. METHOD: Vero fibroblasts in 96-well tissue culture plates were infected with trypomastigote forms of T. cruzi. Amastigotes growth was estimated after 24 and 96 h both by microscopic counts of Giemsa-stained monolayers and enzyme-linked immunoIsorbent assay (ELISA). ELISA was performed directly on the fixed cultures using a rabbit anti-T. cruzi immunoIglobulin as the first antibody and a peroxidase-labelled antirabbit immunoglobulin as the second antibody. Three chemical series of structural analogous of gentian violet, thiadiazines and derivatives of 5-nitrothiophene-2-carbaldehyde as well as three reference compounds (nifurtimox, benznidazole and gentian violet) were then assayed. The anti-T. cruzi activity of all of them had been determined previously by microscopic counting of Giemsa-stained infected cultures. RESULTS: None of the assayed compounds showed better activity than the reference ones, but the application of the enzyme immunoassay to quantify the inhibition of growth amastigotes is of great interest, as it yielded results comparable with microscopic counts. CONCLUSION: ELISA can be applied to pharmacological screening, with some advantages over the microscopic examination, including possible automation, rapidity and objectivity in assessment.
In the field of routine single-dose toxicity studies, we occasionally meet with transient leukocytosis associated with an increase in fibrinogen in beagle dogs within a few days after treatment with the test article. Only a little is known, however, about the toxicological significance of these changes. However, these changes were thought to belong to the category of "Acute Phase Response, APR," which has been known for a long time in connection with injury, trauma or infection. Aiming at proper understanding of these experiences, we surveyed 25 single-dose toxicity studies (7 intravenous bolus, 5 intravenous infusion, 12 oral and 1 subcutaneous treatment, hereafter referred to simply as i.v. bolus, i.v. infusion, oral and s.c.) in beagle dogs, provided with data from hematological examinations. We set the following criteria as a positive response in the present survey: increases of 50% or more in either or both WBC or fibrinogen compared to the predosing value, transiently from Day 1 to Day 3 of the study. Among 25 studies surveyed, about 1/2 of the studies exhibited increases of 50% or more in either or both fibrinogen or WBC counts compared to the predosing values showing dose-dependency transiently on Day 1 or Day 2. These changes were remarkable after intravenous application. Oral application produced similar effects, although the incidence and severity were low compared to the i.v. routes. Regarding blood chemical and hematological changes other than changes in fibrinogen and WBC counts, there were no essential differences between the groups of studies with and without the changes in fibrinogen and WBC counts. These changes were thought to be characteristic and to have occurred as incidents unrelated to other changes. The reported changes seen in single-dose toxicity studies may belong to the category of APR as the non-specific mechanism of living bodies as stated by Burns et al. (1996).
Patient compliance with health care provider advice is a subject of particular importance in developing countries, one that has not been sufficiently studied. This article begins by explaining why this type of research is important and describing the various methodologies used to examine patient compliance in developed nations--notably self-reporting by the patient, collateral reporting by friends or relatives, pill or bottle counting, review of the patient's clinic attendance, review of clinical outcomes, and use of biochemical tracers. The applicability of each of these methods to scenarios commonly found in developing countries is then considered, and the results of the limited compliance research performed in developing countries are described. In general, it is suggested that self-reporting, collateral reporting, and pill or bottle counting can be employed effectively in many Third World situations. The article also notes the importance of standardizing research procedures, provides logistic advice about applying various compliance research methods in Third World conditions, and points up the need to validate the accuracy of the methods used.
Differences in age and sex distribution as well as FAB (French-American-British classification) types have been reported for acute leukemias in several countries. We studied the demographics and response to treatment of patients with acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) between 1989 and 2000 in Teresina, Piau , and compared these results with reports from Brazil and other countries. Complete data concerning 345 patients (230 ALL, 115 AML) were reviewed. AML occurred predominantly in adults (77%), with a median age of 34 years, similar to that found in the southeast of Brazil but lower than the median age in the United States and Europe (52 years). FAB distribution was similar in children and adults and FAB-M2 was the most common type, as also found in Japan. The high frequency of FAB-M3 described in most Brazilian studies and for Hispanics in the United States was not observed. Overall survival for adults was 40%, similar to other studies in Brazil. A high mortality rate was observed during induction. No clinical or hematological parameter influenced survival in the Cox model. ALL presented the characteristic peak of incidence between 2-8 years. Most of the cases were CD10+ pre-B ALL. In 25%, abnormal expression of myeloid antigens was observed. Only 10% of the patients were older than 30 years. Overall survival was better for children. Age and leukocyte count were independent prognostic factors. These data demonstrate that, although there are regional peculiarities, the application of standardized treatments and good supportive care make it possible to achieve results observed in other countries for the same chemotherapy protocols.
The authors previously have reported the effects of neodymiumyttrium-aluminum-garnet (Nd: YAG) laser on the cartilage end-plates (CEPs) in an animal model. However, there is no experimental study in the literature which specifically addresses the effects of the laser on CEP vascularity. The aim of our study is to investigate the vascular response of the CEP to Nd: YAG laser. In this study, sixteen guinea pigs were used. Experimental intervertebral disc (IVD) degeneration was induced in 12 animals by a ventral disc incision to study the effects of Nd: YAG laser on the CEP of the degenerated IVD from the aspects of pathology and radiology. At 2 months after the experimental annular lesion, the CEP vascular channel counts had increased significantly (p = 0.00) in the cranial CEP to 104%, and to 99% in the caudal CEP. In the early period after laser irradiation the vessel counts from both CEPs decreased due to the extensive damage of Nd: YAG laser on disc tissue (p = 0.00). Accordingly, the value of CEP index and MR signal intensity of the CEPs (cranial and caudal) had decreased one month after laser application. Thereafter, both the CEP vascular channel counts and the MR signal intensity remained relatively constant throughout the course of the experiment, but the value of CEP index had increased to 68% of the normal IVD. From the results of present study, it is evident that laser application had a significant negative influence on the CEP vascularization of the degenerated IVD.
In our investigations the qualification of the substances 2-cyanoethyl urea, thymus extract and lithium carbonate was tested for a potential reducing or shortening of the leukocyte-depression in rats after whole-body irradiation. Intravenous applications of 2-cyanoethyl urea and intramuscular injections of thymus extract showed no effect in Wistar rats not only in increase of leukocyte number of peripheral blood, but also in variation of leukocyte portion in differential blood-count. Leukocytes depression appearing in consequence of whole-body irradiation was independent of cyanoethyl urea applications and of thymus extract, too. Lithium carbonate shows a significant increase of leukocytes in peripheral blood in dependence of dosage and frequency of applications. After whole-body irradiation with 7 Gy under lithium therapy, it was shown that on day 6 after irradiation leukocyte number was significantly higher than in controls. Radiogenic leukopenia phase was reduced significantly by lithium.
Haemorrhagic fever with renal syndrome viruses, are members of the family Bunyaviridae. They cause cell to cell fusion from within under acidic conditions. This phenomenon was found to occur under a pH range of between 4.9 to 6.3 for all the viruses examined. The pH range which causes cell fusion was similar to that reported for the La Crosse virus of the Bunyaviridae, hence indicating that this property is a common biological characteristic among this family of viruses. Titration of virus infectivity and neutralizing antibody was done by counting the number of fused cell foci produced in infected Vero cell monolayers after low pH treatment. This method was simpler and more rapid than the ordinary plaque formation method or that of counting infected cell foci by IFA or immunoenzyme assay. In addition, this method may also be applicable in the detection of other enveloped viruses which do not cause a typical cytopathic effect.
UNLABELLED: In many countries, patients treated with therapeutic amounts of (131)I are hospitalized because of radiation safety considerations. To determine when they can return home, radiation levels are intermittently monitored at bedside using a handheld Geiger-MIller (GM) counter, although this procedure can be cumbersome and inexact. METHODS: We have developed and tested a remotely pollable system for continuous radiation monitoring of (131)I therapy inpatients, using readily available hardware and standard telephone lines. The remote detector system, consisting of a palmtop IBM-compatible personal computer, specialized software, PCMCIA modem and miniature serial port-based GM detector, is placed opposite the patient's bed at a fixed distance, and continuous 1-min acquisitions are started. Initially and at least twice daily, the remote palmtop is contacted by modem, and all interval data are uploaded onto the operator's base computer over the telephone line, including measurements taken with the patient in a predetermined standardized position. Continuous minute-to-minute data may be viewed in native form or can be imported into graphing and spreadsheet programs. Points acquired with the patient in standardized position are specially marked to highlight the constant geometry used. The ratio of initial counting rate to administered dose is used to estimate residual (131)I body burden by proportionality. Display of data as a semilogarithmic plot facilitates extrapolation of the activity curves and prediction of the patient's earliest time of discharge. RESULTS: We have characterized the remote GM detector system to confirm accuracy, counting rate linearity and reliability of data transfer. We describe examples that illustrate the applicability and usefulness of this method for remote monitoring of inpatient (131)I therapy levels. CONCLUSION: Monitoring patients with the described remotely pollable GM detector is an accurate and easy-to-implement technique that could conceivably lead to shortened hospital stays for (131)I therapy inpatients. Continuous quantitative data obtained are useful for kinetic and dosimetric analyses, which may be applied to study other gamma-emitting radiopharmaceuticals as well. The flexibility of the technique may permit its use in the monitoring of therapy on an outpatient basis, where allowed.
An assay is described for the determination of the radioactive purity of [14C]oxalic acid preparations and the quantity of [14C]oxalic acid in biological samples. In this method oxalate decarboxylase is used to convert oxalate to formate and CO2. The entire procedure is carried out in a scintillation vial. The 14CO2 released in the enzymic reaction is allowed to diffuse off in a fume hood following acidification. Scintillation fluid is added to reacted and unreacted vials and the radioactivity measured. The loss of radioactivity from the reacted versus the unreacted vials provides the quantity of evolved 14CO2. This value is equal to 50% of the [14C]-oxalate (dpm) present. The radioactive purity of four preparations of [U-14C]oxalic acid was 99.0% while a fifth batch had a purity of 88%. A single batch of [U-14C]oxalic acid had a radioactive purity of 99.0% following storage of an aqueous solution, at -20 degrees C for 7 years. Recovery of [14C]oxalic acid from rat fecal extracts was 101.3%. Eight replicate analyses of a [U-14C]oxalic acid preparation gave a coefficient of variation of 0.3%. Following subcutaneous infusion of [U-14C]oxalic acid to rats, 100.2 +/- 2.9%, mean +/- SD, of the 14C in fecal extracts was present as [14C]oxalic acid (n = 10). The procedure provides a rapid, sensitive, and specific method to determine [14C]oxalic acid. It avoids the time consuming and inconvenient procedure for trapping and counting the evolved 14CO2. The approach used to determine the evolved 14CO2 may find application in other radiochemical methods that require its measurement.
Since the inception of the Supplemental Security Income (SSI) program in 1974, counts of the numbers of cases processed and individuals who were awarded SSI payments have been available. This study breaks new ground, however, by using administrative data to describe in greater detail the characteristics of persons who applied for SSI over a 1-year period. The information on allowance rates is unique because, for the first time, the data have been gathered from the same set of applications. This article tracks the application process to determine whether or not benefits were subsequently received by these SSI applicants in the ensuing 18 months. Of the 1.2 million persons who applied for SSI during the study period, a large proportion were disabled. Among persons whose application was based on age, a greater proportion applied when they attained age 65 than at any other age and they were the most likely to qualify for payments under the program. The data also show how many of the 1.2 million applicants had previously been SSI recipients. In addition to providing demographic and SSI data, the allowance rates are useful in predicting trends in the composition of the caseload.
BACKGROUND: Solar keratoses (SKs) are among the strongest determinants of skin cancer, but little is known about the success of measures to control these common skin tumors. OBJECTIVE: To determine whether daily sunscreen application and/or beta carotene supplementation retards the rate of occurrence of SKs in adults in the medium term. DESIGN: Randomized controlled trial conducted between February 1992 and August 1996. SETTING: General community of the subtropical township of Nambour, Australia (latitude, 26 degrees south). PARTICIPANTS: A total of 1621 adults aged 25 to 74 years. Interventions Participants were randomized to daily use of sunscreen (application of a high-protection sunscreen to their head, neck, arms, and hands every morning) or application of sunscreen at their usual discretionary rate. They were also randomly assigned to take either one 30-mg tablet of beta carotene or one placebo tablet each day. MAIN OUTCOME MEASURE: Change in the prevalent number of SKs in the intervention group relative to change in the control group. RESULTS: The ratio of SK counts in 1994 relative to 1992 was lower in people randomized to daily sunscreen use (1.20; 95% confidence interval, 1.04-1.39) than in those randomized to discretionary sunscreen use (1.57; 95% confidence interval, 1.35-1.84). This 24% reduction is equivalent to the prevention of an average of 1 additional SK per person over that time. A reduction in the rate of change of SK prevalence was also seen in the sunscreen intervention group relative to the discretionary sunscreen group between 1994 and 1996, but it was not significant. No effect on the rate of change of prevalent SK counts was seen among those taking beta carotene supplements relative to those taking placebo tablets. CONCLUSIONS: Daily application of sunscreen retarded the rate of SK acquisition among adults in a subtropical environment, while a beta carotene supplementation of 30 mg/d had no influence on the occurrence of SKs.
The validity and reliability of self-administered joint counts are reported in a group of 32 rheumatoid arthritis patients being followed at a university-based practice located in the Southeast region of the United States, serving low to middle income urban and rural patients. Adequate inter-rater reliability among the patients' and the research assistant's joint counts was obtained for upper (r = 0.74), lower (r = 0.96), and upper and lower extremities (r = 0.89). Convergent validity correlations for pain, helplessness, and the Joint Alignment and Motion scale were found to be adequate. We conclude that rheumatoid arthritis patients can reliably assess their joint counts. Self joint counts along with other validated self-reports of health status may be applicable to busy outpatient settings, as well as in clinical research.