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In this work the anthelmintic potential of the aqueous and hydroalcoholic extracts of two plants used in traditional medicine as antiparasitic, Carica papaya and Plantago major, commonly known as papaya and plantain, respectively, was evaluated. The results obtained showed that the extracts of both plants possess anthelmintic activity causing mortality of C. elegans, in different concentrations. Based on the determination of LC50, the hydroalcoholic extract of P. major leaves (2,663 mg / ml) induced a mortality 40.5% higher than that of the aqueous extract (4,420 mg / ml); whereas in C. papaya the aqueous extract (2,012 mg / ml) caused a mortality 40% higher than the hydroalcoholic extract (3,350 mg / ml). The results are discussed based on the anthelmintic potential of each extract., En este trabajo se evaluó el potencial antihelmíntico de los extractos acuosos e hidroalcohólicos de dos plantas empleadas en medicina tradicional como antiparasitarios, Carica papaya y Plantago major, comúnmente conocidas como papaya y llantén, respectivamente. Los resultados obtenidos indican que los extractos de ambas plantas presentaron actividad antihelmíntica al causar mortalidad de C. elegans, en diferentes concentraciones. Con base en la determinación del CL50, el extracto hidroalcohólico de hojas de P. major (2.663 mg/mL indujo una mortalidad 40,5% mayor que la del extracto acuoso (4,420 mg/mL; mientras que en C. papaya el extracto acuoso (2,012 mg/mL provocó una mortalidad 40% mayor que el extracto hidroalcohólico (3,350 mg/mL. Los resultados son discutidos en función del potencial antihelmíntico de cada extracto.

Our goals are to review the literature on the definition and epidemiology of fecal incontinence (FI), the risk factors involved, available treatment options, and measurement of the quality of life (QOL) of patients with this condition. Articles included for review were searched following the guidelines set by Cochrane Reviewers’ Handbook. FI was defined variously depending upon the duration, type, and amount of leakage. About 17 published papers were reviewed on the prevalence of FI that ranged from 1.4% to 50%. Potential risk factors included perianal injury/surgery, and fair/poor general health. QOL assessment using various grading scales provided an objective method of evaluating patients before and after treatment. Management included medical, physiotherapy, and surgical options. Through the range of various references, a clear definition of FI should be specified, which reflects its epidemiology in the various studies. These differences in definition would significantly affect its prevalence. Many risk factors have been sited but further epidemiological studies are necessary to elucidate FI. Understanding the etiology of the disease is an important initial step to provide adequate treatment of FI. QOL assessment provides objective and subjective method in the analysis of effectiveness of therapy.

Aquifer restoration in the United States is recognized as a technically challenging objective when dense non-aqueous phase liquids (DNAPLs) are present (1). In fact, only a few aquifers impacted by DNAPLs have been restored. Factors that have typically contributed to the lack of successful aquifer restoration include the chemical properties of the DNAPL, the physical properties of the aquifer, the absence of cost-effective technologies, and an incomplete or inaccurate development of a conceptual hydrogeological model for the site. In Latin America, environmental studies historically have been related to biological quality of surface water and groundwater. Recently, the U.S. and Canada have experienced an increased influx of foreign students and professionals interested in studying specialized courses in environmental engineering, or participating in conferences. This exposure to current topics has strengthened the awareness of these professionals regarding groundwater contamination from gasoline-derived compounds and chlorinated solvents. As a result of this increased awareness, Latin American hydrogeologists and environmental regulators have been able to recognize the potential problems that could result from DNAPL spills that may impact groundwater and have learned to approach them using locally available technology and resources. A case study of such an example is presented below.

Interleukin-2 (IL-2) is a multi-faceted cytokine, known for promoting proliferation, survival, and cell death depending on the cell type and state. For example, IL-2 facilitates cell death only in activated T cells when antigen and IL-2 are abundant. The availability of IL-2 clearly impacts this process. Our laboratory recently demonstrated that IL-2 is retained in blood vessels by heparan sulfate, and that biologically active IL-2 is released from vessel tissue by heparanase. We now demonstrate that heparanase digestion also releases a dimeric form of IL-2 that is highly cytotoxic to cells expressing the IL-2 receptor. These cells include "traditional" IL-2 receptor-bearing cells such as lymphocytes, as well as those less well known for IL-2 receptor expression, such as epithelial and smooth muscle cells. The morphologic changes and rapid cell death induced by dimeric IL-2 imply that cell death is mediated by disruption of membrane permeability and subsequent necrosis. These findings suggest that IL-2 has a direct and unexpectedly broad influence on cellular homeostatic mechanisms in both immune and non-immune systems.

Two forced-gradient ground-water transport tests were conducted in the Summers of 1989 and 1990 at Borden, Ontario. The tests were nearly identical in several respects and allow an assessment of the reproducibility of such efforts. In both experiments, carbon tetrachloride, tetrachloroethene, and a conservative tracer were injected as a pulse into the aquifer and monitored as they migrated towards an extraction well. Data were analyzed using moment techniques and fitted with a 1-D transport model accounting for physical nonequilibrium conditions for the sorbing solutes. Visual inspection and simulations of the results indicate that the tests are reproducible. However, results from the moment analyses are less conclusive, perhaps due to data truncation. The differences in the modeling results or the parameter estimates derived from them are likely to have resulted from differences in the experimental conditions or duration. Simulations conducted using either year's fitted parameters are essentially indistinguishable from a practical point of view.

A field lest to evaluate the applicability of an oxygon-releasing compound (ORC) to the rernediation of ground water contaminated with benzone and toluene was conducted in the Borden Aquifer in Ontario. Canada. Benzene and toluene were injected as organic substrates to represent BTEX compounds, bromide was used as a tracer, and nitrate was added to avoid nitrate-limited conditions. The fate of the solutes was monitored along four lines of monitoring points and wells. Two lines studied the behavior of the solutes upgradient and downgradient of two large-diameter well screens filled with briquets containing ORC and briquets without ORC. One line was used to study the solute behavior upgradient and downgradient of columns of ORC powder placed directly in the saturated zone. The remaining line was a control. The results indicate that ORC in both briquet and powder form can release significant amounts of oxygen to conlaminated ground water passing by it. In the formulation used in this work, oxygen release persisted for at least 10 weeks. Furthemiore, the study indicates that the enhancement of the available dissolved oxygen content of at least 4 mg/L each of the ground water by ORC can support biodegradation of benzene and toluene dissolved in ground water. Such concentrations are typical of those encountered at sites contaminated with petroleum hydrocarbons; therefore, these results suggest that there is promise for ORC to enhance in situ biodegradation of BTKX contaminants at such sites using passive (nonpumping) systems to contact the contaminated ground water with the oxygen source.

A forced-gradient test of solute transport was conducted adjacent to the site of a previous natural gradient test to allow comparison of results obtained from the two types of field tests. In the forced-gradient test, one inorganic tracer and four organic solutes (carbon tetrachloride, trichloroethylene, tetrachloroethylene, and hexachloroethane) were injected for 48 hours. The migration of the dissolved chemicals toward the extraction well was monitored by multilevel samplers and a partially penetrating monitoring well. Moment analyses of the solute breakthrough curves at the multilevel points provide model-independent insight into the variation of hydraulic conductivity and organic solute retardation in the aquifer. The estimated retardation factors fall within the range estimated in the previous natural gradient test. Sorption distribution coefficients inferred from the transport data indicate spatial variability of sorption for all solutes, with mean values and ranges similar to those observed in laboratory studies of core or bulk samples. Some evidence was obtained for spatially variable in situ transformation of hexachloroethane.

A variety of evidence suggests that the fluids forming stratiform and red-bed copper deposits derived their Cu, Ag, and other metals from adjacent red sandstones and shales. Copper and Ag are soluble in moderately concentrated chloride brines at intermediate oxidation states, but published data suggest that Cu is strongly adsorbed on goethite and hematite at pH near 7 and temperatures of 0 degrees to 100 degrees C. Also, Pb, Zn, Co, and Ni are soluble in chloride brines, but are only present in some red-bed Cu deposits. To examine variability in relative adsorption of 0.5 mg/l Ag, Co, Cu, Ni, Pb, and Zn, adsorption on goethite (195 m 2 /l) has been measured as a function of pH (5-9), Cl (super -) (0, 1M, 4M,), temperature (25 degrees C, 50 degrees C), and redox state (air, Fe (super +2) -goethite). Under oxidized conditions at 25 degrees C and 1M Cl, the order of decreasing adsorption is Cu-Pb-Zn-Co-Ni-Ag, with Cu and Pb almost completely adsorbed at pH values greater than 6. However, in 1M Cl at 25 degrees C with Eh buffered by Fe (super +2) -goethite, the order of decreasing adsorption is Pb-Zn-Co-Ni-Cu(-Ag?), and less than 50 percent of the Cu is adsorbed at pH 7. An exploratory experiment with 3M NaCl + 1M Na 2 SO 4 at 25 degrees C with about 4,000 m 2 /g of hematite as adsorbent and 75 mg/l Cu, Ag, Zn, Pb, and Co and 40 mg/l Fe (super +2) was conducted to approximate conditions in a red-bed pore fluid during diagenesis. An appreciable fraction of the Cu and Ag remained in solution at pH 7, but Pb, Zn, and Co were completely adsorbed. Based on this data, the observed range of metal associations (Cu, Cu-Ag, Cu-Co, Cu-Zn-Ag, etc.) in red-bed and stratiform copper deposits seems explainable by variations among districts in pH, Eh, temperature, major element content of pore fluid, and Fe oxide character of the diagenetic environment. Similar adsorption phenomena may account for varying metal ratios in other low-temperature ore deposits and in noneconomic metal enrichments.

Field tests of organic solute transport behavior have often been monitored using small-diameter wells (miniwells). To determine if experimental results could be significantly biased by sorption to, desorption from, or diffusion through sampling lines, dissolved concentrations of tetrachloroethene and carbon tetrachloride were measured in ground water samples collected simultaneously from the same spatial location during a forced-gradient test in the Borden aquifer using polytetrafluoroethene (PTFE) and stainless steel miniwells (1/8-inch O.D.). A semiautomated organic analytical system was used on-site to obtain real-time results, which avoided sample holding problems and permitted optimizing sampling times. The breakthrough curves (plots of concentration vs. time) for both organic compounds indicate that under the conditions of this experiment (low organic solute concentrations, short exposure time of sampling lines to the plume, adequate flushing of sampling lines) there is no significant difference between concentration histories (breakthrough curves) collected using a polytetrafluoroethene sampling line and those collected using a stainless steel sampling line. This suggests that organic solute tailing seen in this and also in a similar transport experiment previously conducted at the site is the result of transport processes in the aquifer rather than an artifact introduced by the PTFE miniwells.

The effects of aliphatic alcohol co-solvents on the nature of inclusion complexes formed between 2-anilinonaphthalene-6-sulfonic acid (2,6-ANS) and β- or γ-cyclodextrin were studied with the use of steady-state and time-resolved fluorescence spectroscopy. Complementary information about the effects of alcohol on cyclodextrin (CD) inclusion complexation has been obtained. The fluorescence lifetimes are recovered from multifrequency phase and modulation experiments in concert with a global analysis scheme. In all cases, the best fitting model contained two decay times. One of the components of the intensity decay is short lived and discrete and the other is a longer-lived distributed component. Evidence from the emission peak intensity, the center and width of the lifetime distribution, and the molar fraction of lifetime components indicates that alcohol modifiers have two distinct effects on the cyclodextrin inclusion complex. First, alcohol co-solvents can disrupt the 2,6-ANS-CD complex through competitive binding with the CD cavity, and to a lesser extent they increase the bulk solvent hydrophobicity. Second, alcohols can enhance the stability of certain 2,6-ANS inclusion complexes by formation of higher-order complexes (2,6-ANS-CD-ROH n). These two effects are governed by the cavity size and the structure and concentration of the alcohol co-solvents. These observations are consistent with the roles of the van der Waals interactions, the hydrophobic effect, and the stearic effects as important factors in CD inclusion complexation. Finally, the average rotational correlation time, recovered from steady-state anisotropy experiments, indicates that the rotational dynamics of the 2,6-ANS-CD complex are regulated by the size and concentration of the alcohol co-solvent.

Over the last several decades the communications industry has developed small, high-light transmitting fiber-optic materials. Because of their inherently non-perturbing nature fiber optics have found wide spread use in many diverse areas of analytical spectroscopy. Of all the spectroscopic techniques, fiber-optic-based fluorescence has probably enjoyed the greatest popularity. Unfortunately, while successful analyses have been achieved via fiber-optic probes, only a fraction (that is, spectral information) of the total information content from the fluorescence process has been utilized. In this paper, recent results from our laboratory are presented for the successful implementation of the remaining dynamic and steady-state fluorimetric measurements in conjunction with fiber-optic sensing.

BACKGROUND: Human immunodeficiency virus (HIV) prevalence is relatively lower in Sri Lanka than in other Asian countries; however, the number of HIV-infected persons has rapidly increased in recent years. METHODOLOGY: A baseline study on HIV, acquired immunodeficiency virus (AIDS), and sexually transmitted infections (STI) knowledge, attitude, and practice was conducted at two construction sites in Sri Lanka from January to February 2007 to design an effective intervention strategy for the construction workers. RESULTS: Among 611 respondents (mostly males, mean age 32.8 years), nearly two-thirds lived away from home. Knowledge was fairly good on AIDS prevention but poorer on STI than on HIV. Some misconceptions were also observed. A high percentage did not consider HIV/AIDS as their own personal issue, and over 50% respondents expressed discriminatory attitudes towards HIV positives. Condom access was limited due to social and cultural norms. Mobility was not significantly associated with practice of prevention of HIV and STI. CONCLUSION: This study showed that the construction workers were not specially at higher risk of HIV at that time. In order to minimize the potential risk of infection, however, it would be effective to reduce stigma and discrimination among them through the prevention program, working together with community or religious leaders in the areas. More comprehensive assessment among other population groups would also be beneficial to identify their risk of infection

Background: Rabies remains endemic in Sri Lanka despite a strong government patronized anti-rabies campaign. Personal, cultural or religious beliefs have been thought to influence health practices that could render rabies prevalent in the country. Methodology: The knowledge, attitudes, and beliefs of 580 household heads/members from Nuwara Eliya District, Sri Lanka, regarding rabies were explored through a structured questionnaire. An improvement/deterioration in their knowledge and practices after the use of information and education campaign (IEC) materials was assessed through a repeat exploration at an interval of four weeks. Results: Respondents showed inclination toward animal birth control (60%) rather than elimination methods (24%). There was disparity between pet owners‟ enthusiasm to take pets for rabies inoculation (57%) and their ability to show dog vaccination cards (40%). Almost twice more pet owners than non-pet owners believed that it is their responsibility to control the population of roaming pet dogs (aOR=1.78; 95% CI: 1.14 to 2.76). The rabies leaflets were very effective in informing the people on how to deal with rabid animals, the earliest schedule for anti-rabies vaccine (ARV), and repeat vaccination. Conclusions: Awareness and proper attitude toward rabies management and canine population control are adequate among the rural Sinhalese and Buddhist populations of Sri Lanka; however, their current health practices should be improved. The rabies KAP could be further enhanced through the use of IEC materials.

A selective fiber-optic-based immunosensor for haptens is described and characterized. In order to construct a sensor for different analytes, a prescribed reaction protocol is followed and only the recognition element [F(ab′) antibody fragment] has to be changed. The dynamic range of this sensor is about two orders of magnitude and the detection limits are at least 25 nM (25-μ1 volume). By using steady-state fluorescence and classical ultra-high-vacuum surface analytical techniques, the effects of regeneration media, reaction and storage times and interferents on the sensor response were studied.

Fluorescence lifetimes are reported for a series of anilinonaphthalene sulfonate (ANS) probe molecules complexed with β-cyclodextrin (β-CD). The fluorescence decay kinetics are recovered by multifrequency phase and modulation measurements in concert with a global analysis scheme. In all cases studied, a continuous Lorentzian distribution of lifetimes is observed, resulting from the dynamical nature of the ANS-β-CD complex and free ANS. Trends are discussed and comparisons made between bound and free fluorophore and between different isomeric ANS structures.

A bifurcated fiber-optic sensor is reported that uses immobilized β-cyclodextrin (β-CD) as the sensing agent. The sensor forms moderately selective inclusion complexes between β-CD and many guest molecules. On complexation, a weakly fluorescent molecule often exhibits a significant increase in emission yield. The linear dynamic range of this sensor extends well over 2.5 orders of magnitude. Detection limits (signal-to-noise ratio=3) are as low as 4 nM for sample volumes as small as 15μl (60 fmol). This is an improvement of over two orders of magnitude compared with detection with a conventional “bare” fiber-optic probe. The sensor is simple to fabricate, has a useful lifetime of at least 5 months, is suitable for laser or arc lamp excitation sources and can be reconditioned rapidly.

Since 1957 Japan has successfully eradicated human and animal rabies through registration, confinement and compulsory vaccination of family dogs, and elimination of stray dogs. However, in November 2006, two cases of human rabies infections were reported in the country. These patients were bitten by dogs during travel in the Philippines, and did not receive pre- and post-exposure prophylaxes. With the mounting numbers of Japanese travelers every year, the risk of infection increases especially to those who visit regions where the disease is endemic. In this paper, we shall discuss the two recent human deaths from rabies, review the current situation and control measures in Japan and surrounding countries where the disease is prevalent, summarize precautionary measures for travelers, and suggest public health strategies to prevent the re-introduction of rabies in the country.

The primary objective of this study was to determine the level of knowledge, attitudes and practices (KAP) of rabies management and control of a sample population. The secondary objective was to compare the KAP with respect to rabies management and control between urban and rural areas and between pet and non-pet owners. This cross-sectional study was carried out by conducting face-to-face interviews using structured questionnaires among 1570 respondents from selected households in the Kandy District, Sri Landa. Approximately 58% of the sample population was pet owners. Among all the respondents, there was a high level of awareness (90%) that dogs are the most common rabies reservoir, that the disease is fatal (79%), and that rabies can be prevented by vaccination (88%). Most of the subjects (96%) would seek treatment from a doctor or a hospital after being bitten by a dog. Although 76% of the respondents said that their pet dogs were vaccinated, only one-half were able to present a vaccination certificate upon request. The subjects from the urban areas would submit the head of an animal for rabies evaluation (69%) compared with those from the rural areas (57%). Pet owners (93%) are more aware that dog rabies vaccines are available from authorized offices than non-pet owners (87%). The level of awareness of rabies and the level of receptiveness to rabies control measures are high. There is a difference in the attitudes and pet care practices relevant to rabies control between urban and rural areas. Pet owners tend to be more cooperative to rabies control activities. The attitudes and practices of the respondents may reflect the inaccessibility of facilities and the lack of services that would enable community participation in rabies control.

This paper discusses the history of emerging infectious diseases, risk communication and perception, and the Supercourse lectures as means to strengthen the concepts and definition of risk management and global governance of zoonosis. The paper begins by outlining some of the key themes and issues in infectious diseases, highlighting the way which historical analysis challenges ideas of the 'newness' of some of these developments. It then discusses the role of risk communication to public accountability. The bulk of the paper presents an overview of developments of the Internet-based learning system through the Supercourse lectures that may prove to be a strong arm for the promotion of the latest medical information particularly to developing countries.

Since the advent of bovine spongiform encephalopathy (BSE) in the United Kingdom in 1986, new BSE cases have recently become rare. However, in Japan and the United States, positive cases have started to be seen recently. The rise in BSE cases paved the way for the human form of this disease, the variant Creutzfeldt-Jakob disease (vCJD). The observed trends in the UK may be attributed to effective implementation of public health policies coupled with increased vigilance through advancement in science and technology, or they may well be a reflection of the natural disease progression. We aim to discuss the BSE chronology of events, and compare examination methods, costs and cost-efficiency, management, and public policies of Japan, Europe, and the USA.

Millions of dollars are spent in the United States each year to design, construct, and operate systems intended to remediate groundwater impacted by dense non-aqueous phase liquids (DNAPLs), such as trichloroethlene (TCE) and tetrachloroethene (PCE), or light non-aqueous phase liquids (LNAPLs), such as gasoline, diesel, and jet fuel. However, several recent studies suggest that many of these groundwater remediation systems may operate for decades without restoring groundwater to background conditions. This paper examines the potential economic impacts of continuing the current regulatory approach to remediation of NAPL-contaminated aquifers versus considering regionally contaminated aquifers as large storage basins instead of pristine resources. Treating water at the point of extraction when needed, provides an equivalent benefit and may be more practical and cost effective than attempting to restore aquifers to background conditions at the point of contamination.

We report the results of a trial of recombinant leukocyte A interferon in previously treated patients with non-Hodgkin's lymphoma who were no longer responsive to chemotherapy. Patients received recombinant leukocyte A interferon (50 X 10(6) U per square meter of body-surface area) by intramuscular injection three times weekly for three months or longer. Forty-five patients were enrolled in the study, and 37 were evaluated for a response. Thirteen of 24 (54 per cent) evaluable patients with low-histologic-grade non-Hodgkin's lymphoma had objective responses (nine partial responses and four histologically confirmed complete responses). Two of six (33 per cent) with intermediate-grade lymphoma responded (one partially and one completely), and one of seven (14 per cent) with high-grade lymphoma had a partial response. The median duration of responses was eight months. Four of the five complete responders have continued to receive maintenance interferon and have been in complete remission for 3, 7, 9, and 12 months, respectively; one had a recurrence at a site of previous disease seven months after interferon had been stopped. Side effects were noted in most patients. All 16 responders had been heavily pretreated with combination chemotherapy, including doxorubicin in 8 of the 16. These results suggest that recombinant leukocyte A interferon may be an effective new therapy for some patients with low- and intermediate-grade non-Hodgkin's lymphoma.

Recombinant leukocyte A Interferon Is a highly purified single molecular species of alpha-interferon prepared by recombinant DNA methods. In 1982, a phase II trial to evaluate the efficacy of recombinant leukocyte A Interferon for patients with previously treated chronic lymphocytic leukemia was begun, and 19 patients were entered In this study. Patients received one of two dose schedules depending on their pretreatment platelet counts. Those with platelet counts greater than 100,000/mm 3 received 50 × 10 6 units/m 2 intramuscularly three times weekly, with dose reductions to 25 × 10 6 units/m 2 and 5 × 10 6 units/m 2 for unacceptable toxicity. Those with platelet counts less than 100,000/mm 3 received 5 × 10 6 units/m 2 intramuscularly three times weekly. Toxicity was dose-dependent and included fever, chills, fatigue, anorexia, myalgias, headache, leukopenia, and thrombocytopenia. Response was evaluable in all but one of the patients entered In this study. Two of the 12 patients treated with 50 × 10 6 units/m 2 had a partial response, three had no response, and seven had progressive disease. Of the six patients starting at 5 × 10 6 units/m 2 in whom response was evaluable, two had no response and four had progressive disease. Five patients with progressive disease (three at 50 × 10 6 units/m 2 and two at 5 × 10 6 units/m 2 ) had an acceleration of disease while receiving recombinant leukocyte A Interferon. It Is concluded that the dose and schedule of recombinant leukocyte A interferon therapy tested in this study are not effective in previously treated patients with advanced chronic lymphocytic leukemia.

Mercury levels were determined in the urine of seventy dentists and their assistants engaged in full-time restorative dentistry. Twenty nondental personnel were used as controls. The dental personnel were divided among six separate clinics having two basic designs. Ten morning specimens of urine were collected from each subject over a period of 2 weeks, and mercury was determined in duplicate in each specimen by atomic absorption spectrophotometry. Mean urinary mercury values, ranging from 3 to 17 μg per liter and 5 to 124 μg per liter, were obtained for the controls and dental personnel, respectively. Compared to the controls, 65.7 per cent of all personnel and the over-all data from three clinics showed significantly elevated levels of urinary mercury. In one clinic consisting of twelve dental units in one large room, all personnel showed significant elevations in urinary mercury. A comparison of restorative work done in a given period with the mean urinary mercury value for each clinic suggests that, with regard to mercury hygiene, the single-large-room design is less desirable than a situation in which individual dental units are located in separate but adjoining rooms.

This experiment describes resorption rate, light and electron microscopic appearance of the implant site, and tissue distribution and route of elimination of radioactivity from carbon-labelled polylactic acid implants. Fifty-six rats received abdominal implants and were serially sacrificed at 28, 56, 84, 112, 140, 154, and 168 days. Urine and fecal output was measured for radioactivity, along with implant site and several tissues at the time of sacrifice. Tissue distribution of activity was negligible. Resorption rate of the implant was linear with 63.2% remaining after 168 days. Elimination of radioactivity was via respiration, approximately 29.4% by this route. Histologically, the implant was invaded rapidly along septal defects or slowly on broad fronts. Invading cells were characterized either by large double-walled vacuoles or by large accumulations of mitochondria and microvesicles adjacent to the implant surface. The long duration of this type of implant may be an important consideration in surgical applications.

Changes in osseous tissue after injury were studied in monkeys with the use of thermogravimetric analysis (TGA) and mechanical strength measurements. An exponential relationship was found to exist between strength and weight loss for repair tissues 3 to 8 weeks old. The quantitative techniques investigated seem promising for the improved characterization of mineralized tissue.

Young adult guinea pigs maintained on a normal diet were subjected to an experimental bone injury technique and given daily intraperitoneal injections of either a zinc chelate or a zinc salt from the day of injury to death. Animals were sacrificed at four weekly intervals. Bone obtained at the time of injury and repair tissues obtained at death were analyzed for zinc content. Healing was evaluated histologically. The administration of either zinc cysteamine-N-acetic acid (ZnCAA) or zinc sulfate resulted in accelerated bone healing. Best results were obtained with the ZnCAA. There appeared to be a good correlation between increasing levels of zinc accumulation in repair tissues and healing acceleration. Weight gain patterns indicated that there were no toxic effects due to the chelate injections but some possible growth retardation with the levels of zinc sulfate administered.

This paper examines the synthesis of a toughened elastomer fromVernonia galamensis seed oil by reacting vernonia oil with vernonia oil-derived suberic acid (octanedioic acid), and cross-linking the pre-polymer in the immediate presence of cross-linked polystyrene preparedin situ. The paper also demonstrates that the progress of reaction can be followed by monitoring the generation of hydroxyl groups using infrared spectroscopy. Analysis of some crystalline material on the cooler parts of the reaction vessels revealed the presence of component fatty acids of vernonia oil. Transmission electron microscopy characterization of the synthesized toughened elastomer suggests that vernonia oil-suberic acid polyester and polystyrene polymer are interpenetrating.

Thermodynamic parameters and stoichiometries for the binding of anilinonaphthalenesulfonates to beta-cyclodextrin are obtained from steady-state fluorescence intensity and anisotropy measurements. Specifically, formation constant, enthalpy, and entropy values are obtained for complexes of beta-cyclodextrin with eight different substrate molecules at five different temperatures and six different pH values, and their associated errors are given. We propose an explanation of the relative magnitudes of the values obtained with regard to the geometry of the substrate and the importance of the various noncovalent interactions responsible for the complexation.

Biochemical and clinical signs of tumor lysis syndrome developed in a 57-year-old man with recurrent T cell lymphoma during therapy with recombinant leukocyte A interferon. When therapy was Interrupted due to thrombocytopenia and later resumed, biochemical changes compatible with tumor lysis recurred. This is the first case of tumor lysis syndrome observed during therapy with a biologic response modifier, a new class of agents entering cancer clinical trials. The atypical features of the clinical presentation and possible implications of these observations are discussed.

Mercury and 12 clinical chemical determinations were done on the blood samples of 1,555 dentists. The dental practice characteristics of each participant were determined by questionnaires. Seventy-seven percent of all the dentists displayed blood mercury values in the range 0 to 10 ng/ml. The mean for all dentists was 8.2 ng Hg/ml blood. The means for general dentists and specialists were 8.8 and 6.3 ng Hg/ml blood, respectively. Overall, no significant correlations were found in a comparison of blood mercury levels with clinical chemical data and with dental practice characteristics. However, general practitioners with higher blood mercury values tended to show dental practice characteristics that were conducive to producing the higher values found. The data indicate that dentists in the United States, as a group, practice good mercury hygiene.

Lower first molar extractions were performed on white rats given daily intraperitoneal doses, from the day of extraction to sacrifice, of zinc, either as the sulfate or as the chelate complex zinc cysteamine-N-acetic acid. A notable acceleration was seen in the healing of alveolar bone in the zinc-treated animals. The greatest improvement in the rate of healing was seen in the chelate-treated animals. There was some indication, on the basis of animal weights recorded during the experiment, that intraperitoneal injection of ZnSO4 may have had some toxic effect.

Many different materials have been used by orthopedic and maxillofacial surgeons to repair bony deficiencies. This review is limited to those materials that have been shown to be tissue-tolerant and biodegradable, and to include certain synthetic polymers and ceramics. There are many possible applications for these agents. Special terms and concepts are germane to an understanding of polymers and ceramics.