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We previously reported that both cannabidiol (CBD) and low‑dose naltrexone (LDN) exhibit complex effects on G‑protein coupled receptors, which can impact the expression and function of other members of this superfamily. These receptors feed into and interact with central signalling cascades that determine the ease by which cells engage in apoptosis, and can be used as a way to prime cancer cells to other treatments. The present study was designed to investigate the effect of combining these two agents on cancer cell lines in vitro and in a mouse model, and focused on how the sequence of administration may affect the overall action. The results showed both agents had minimal effect on cell numbers when used simultaneously; however, the combination of LDN and CBD, delivered in this specific sequence, significantly reduced the number of cells, and was superior to the regimen where the order of the agents was reversed. For example, there was a 35% reduction in cell numbers when using LDN before CBD compared to a 22% reduction when using CBD before LDN. The two agents also sensitised cells to chemotherapy as significant decreases in cell viability were observed when they were used before chemotherapy. In mouse models, the use of both agents enhanced the effect of gemcitabine, and crucially, their use resulted in no significant toxicity in the mice, which actually gained more weight compared to those without this pre‑treatment (+6.5 vs. 0%). Overall, the results highlight the importance of drug sequence when using these drugs. There is also a need to translate these observations into standard chemotherapy regimens, especially for common tumour types where treatment is often not completed due to toxicities.

Objective: The aim of this study was to investigate associations between four categories of maltreatment and substance use among adolescents., Method: All 10th through 12th graders n = 2,187) at six public high schools in a rural Oregon county filled out an anonymous survey that included questions about their experience of emotional, sexual, and physical abuse and their use of a variety of substances. Substance use was subsequently categorized as: (1) tobacco use, (2) alcohol use, and (3) illicit drug use. Experience of maltreatment was subsequently categorized as: (1) no type of maltreatment, (2) emotional abuse, (3) physical abuse, (4) sexual abuse, and (5) sexual and physical abuse., Results: Results showed that all four categories of maltreatment were associated with increased levels of all three categories of substance use. Statistical comparisons of the magnitude effects of different types of maltreatment on substance use indicated a linear trend with the effects of emotional abuse being significantly lower than those of physical or sexual abuse, and the effects of the combination of physical and sexual abuse being significantly higher than the other types., Conclusion: Results suggested that all types of maltreatment, including emotional abuse, are related to significantly higher levels of substance use and should be considered serious risk factors for substance use during adolescence. Results also indicated that the strength of association between maltreatment and substance use varies by type of maltreatment. Youth who have experienced both physical and sexual abuse are at especially high risk of substance use., (Copyright 2004 Elsevier Ltd.)

Background: The effect of hospitalization on nursing home patients with pneumonia is not known. We hoped to learn more about the effect of hospitalization on outcome by comparing patients with pneumonia from 2 nursing homes., Methods: Using a retrospective chart review, we compared a total of 129 patients with pneumonia from 2 community nursing homes in upstate New York over a 2-year study period. The main intervention measures were treatment in the hospital or treatment in the nursing home. The main outcome measures were resolution or mortality at 6 weeks., Results: Nursing home B had a hospital admission rate for pneumonia (38.8%) that was double that of nursing home A (19.4%). The patient populations were judged to be similar, and the overall mortality outcome for both (weighted average = 24.8%) was essentially identical., Conclusions: Doubling the hospital admission rate in 1 of 2 similar groups of nursing home patients with pneumonia was not associated with an improved mortality outcome at 6 weeks.

Background: Bronchopulmonary infections have been considered the leading cause of hospital admissions and death in the nearly 2 million nursing home residents in the United States. Very little is known about the treatments and outcomes of this entity. The purpose of our study was to document the incidence, treatments, and outcomes of nursing-home-acquired pneumonia in hospitalized and nonhospitalized patients., Methods: We conducted a retrospective chart review during a 24-month period of patients from two community nursing homes in upstate New York with a total average population of 330 residents. The main outcome measure was 6-week mortality., Results: Pneumonia was diagnosed in 129 patients, whose overall 6-week mortality rate was 24.8 percent. Ninety-one patients were cared for in the nursing home, and 38 patients were hospitalized. Six-week mortality rate for the nonhospitalized group was 18.7 percent. The hospitalized group's 6-week mortality rate was significantly higher at 39.5 percent. There were no significant differences between the hospitalized and nonhospitalized groups before their diagnosis that predicted outcome., Conclusions: For many patients nursing-home-acquired pneumonia can be successfully treated in a nursing home with oral antibiotics at a considerable cost savings when compared with hospitalization.

Training of physicians to meet the health care needs of rural residents has long been a priority of the University of Oklahoma College of Medicine. With establishment of the much imitated Rural Preceptorship Program in 1948, the college launched an ongoing series of efforts all directed toward increasing the number of graduates choosing to practice in rural locations. In addition to the required senior Preceptorship Program, a series of educational programs is available in each year of medical school, actually beginning prior to freshman enrollment. As a result, the college now offers a comprehensive series of educational experiences involving not only four years of medical school, but graduate training in the primary care specialties as well. This report summarizes the various activities of the college that now make up the rural emphasis program, all of which are designed to help ensure an adequate supply of physicians for rural Oklahoma.

Efforts in recruitment and retention of students by the University of Oklahoma College of Medicine have resulted in an increased size of applicant pool to the college over the past three years. Curriculum changes and programmatic innovations have provided new opportunities for students and incentives to remain in the State of Oklahoma. Continuing and expanding recruitment efforts can be enhanced by the active participation and support of the physicians of the state.

Normal C57BL/6J peritoneal cells exhibited a decreased phagocytosis when cultured with a cell wall antigen of Cryptococcus sp. and lymphocytes from mice infected with C. neoformans. Direct cell-to-cell interaction was not required in that supernatant fluids from cultures of lymphocytes from infected animals could be incubated with normal macrophage monolayers to give comparable suppression. The induction of the suppressor factor required specific cryptococcal antigen; however, suppression at the macrophage level was nonspecific in that the phagocytosis of C. neoformans and Saccharomyces cerevisiae were both decreased. Suppression appeared with lymphocyte supernatants taken from mice infected for 14 days and thereafter. The factor was heat stable, trypsin sensitive, and allospecific.

Our previous reports have shown that animals inoculated for 8 weeks with 1 X 10(5) pseudohyphal, avirulent C. neoformans exhibited prolonged survival upon challenge with virulent cryptococci. This paper described a transient phase of immunosuppression which occurs during the initial weeks of the immunization protocol. Animals injected with pseudohyphal organisms had depressed responses to T and B-cell mitogens. In addition, they had lowered responses to immunization with sheep erythrocytes. Both humoral and cell mediated responses were affected.

Responses of the rhesus monkey to the administration of live Escherichia coli organisms during an observation of 0--27 hours were studied. Nine monkeys were infused for 30 minutes with live E coli organisms, the dose ranging between 7.6 X 10(9) and 3.0 X 10(11) organisms/kg. Three of nine animals survived for 24 hours or longer. Nonsurvivors demonstrated significant hypotension, hypoglycemia, and hypoinsulinemia, while survivors showed lesser degrees of physiologic derangement. Findings were hepatic sinusoidal fibrin thrombi and hepatocellular damage accompanied by elevated serum enzymes. The kidney did not show glomerular fibrin thrombi; however, tubular lesions were clearly evident and increases in blood urea nitrogen levels and endogenous creatinine were documented. Lungs of animals surviving longer contained fewer polymorphonuclear leukocytes and platelets than were seen in acute shock studies. This study emphasizes the importance of monitoring the nonhuman primate during an extended time period, since many significant pathophysiologic responses occur after eight hours of observation.

Three antigens were compared for their ability to detect immune responses in C57Bl/6 mice sensitized to Cryptococcus neoformans. Elicitation of responses in vitro was greatest with a urea extract antigen, followed in efficiency by an alkali extract and a soluble capsular polysaccharide preparation. The reactivity paralleled the protein content of the preparation.

A 76-year-old man with chronic obstructive pulmonary disease who developed P multocida pneumonia and bacteremia has been described. The infection was treated with antibiotics, and the patient recovered. Pasteurella multocida is known to infect many species of animals. The instances of human infection due to this organism are frequently associated with exposure to animals. Pulmonary infection occurs principally in patients with underlying chronic bronchopulmonary disease.

An alkali-soluble, water-soluble cell wall fraction of Blastomyces dermatitidis, designated B-ASWS, was evaluated as an antigen for detecting in vivo (skin tests) and in vitro migration inhibition factor (MIF) production and lymphocyte transformation (LT) responses in Blastomyces-infected guinea pigs. The biological activity of B-ASWS was compared with that of blastomycin KCB-26. The superiority of B-ASWS, in terms of its sensitivity and specificity, was evident in in vivo and in vitro assays. Skin tests responses were obtained in 21 of the 24 Blastomyces-infected guinea pigs, whereas only one of the 14 Histoplasma-infected guinea pigs were significantly greater than those obtained using cell populations from Histoplasma-infected or noninfected guinea pigs. The con-MIF and LT in peritoneal exudate cells and lymph node cells of homologuosly infected animals. In each biological system, the response of the Blastomyces-infected guinea pigs were significantly greater than those obtained using cell populations from Histoplasma-infected or non-infected guinea pigs. The contrasting efficacy of B-ASWS as compared with blastomycin KCB-26, suggests that the cell wall antigen will be a useful tool for detecting cell-mediated immune responses in blastomycosis.

A T-suppressor factor which inhibits the phagocytic activity of a macrophage subset has been further characterized. This suppressor factor was first described for a murine model of cryptococcosis but was later found to be common to models of immunologic unresponsiveness. The suppressor factor was produced when suppressor cells were cultured in the presence of specific cryptococcal antigen. It could not be extracted from spleen cells and was not induced by antigen in cultures of lymph node cells. The suppressor factor was filtered through Amicon filters of 100-kilodalton (kDa) exclusion limit but was retained by filters excluding molecules of less than 50 kDa. By Sephadex G-100 chromatography, the factor eluted just ahead of bovine serum albumin (68 kDa). The activity of the suppressor factor could not be inhibited by anticryptococcal antibody, but it was inhibited by anti-I-J alloantiserum of the same genotype as the lymphocyte which produced the factor. Absorption with an encapsulated strain of Cryptococcus neoformans removed the suppressor factor from culture supernatants, while absorption with a nonencapsulated mutant or an unrelated yeast cell had not effect. On the basis of these observations, it was apparent that the suppressor factor was idiotypic in nature and that I-J and/or the I-J-interactive molecule played a role in the function of the suppressor factor. The requirement for antigenic stimulation for the production of suppressor factor in vitro distinguished it from the T-suppressor factor 3 described by others which regulates delayed-type hypersensitivity in cryptococcosis.

Subpopulations of spleen cells responsible for responsiveness and unresponsiveness to cryptococcal antigen in vitro were identified. Lymphocytes which responded in lymphocyte transformation (LT) assays were nylon wool nonadherent and theta antigen positive. These lymphocytes required the presence of an accessory cell which could be supplied by normal peritoneal exudate cells. Spleen cells taken from mice which had been infected for 3 to 15 days were tested to determine their ability to respond to cryptococcal antigen in LT assays. A minimal response was detected at the ninth day of infection. The response of infected spleen cells was attributed to a nonadherent lymphocyte. Nonadherent spleen cells of infected animals had enhanced responses after removal of adherent cells and addition of normal peritoneal exudate cells. Suppressor cells were detected in the spleens of infected mice by the 12th day of infection and thereafter. A nonadherent suppressor cell was identified, but indirect evidence suggested that an adherent cell could also be present in infected spleens.

Soluble extracts of Cryptococcus neoformans were examined for their ability to induce a macrophage-regulatory T-suppressor cell known to appear in the spleens of mice infected with cryptococci. Suppressor cells were induced by injection of extracts of encapsulated or thinly encapsulated strains of cryptococci. Dose-response analysis showed that as little as 25 micrograms of soluble capsular polysaccharide antigen could induce significant suppressor cell activity, with maximum suppression occurring at a dose of 100 micrograms. The suppressor cells appeared within 1 week of injection of antigen and persisted for at least 2 months. Suppressor cells were induced in animals given tolerogenic doses of levan, human gamma globulin, and soluble capsular polysaccharide antigen. When these same antigens were administered in immunogenic form, no suppressor cell activity was detected. Therefore, the suppressive mechanism was common to models of immunologic tolerance and was not unique to cryptococcal disease or cryptococcal capsular polysaccharide antigen. The phagocytosis-inhibiting lymphokine produced by the suppressor cell population completely inhibited the phagocytic activity of only a portion of peritoneal exudate cells. Other macrophages in the population were not totally inhibited but exhibited a reduction in the number of yeast cells engulfed.

An alkali-soluble water-soluble extract of Blastomyces dermatitidis yeast-phase cell walls was tested for its ability to elicit a response in lymphocytes isolated from the peripheral blood of Blastomyces-infected guinea pigs. Sequential preparations of the antigen were reproducible and specific in the in vitro lymphocyte transformation assay. Cross-reactivity of the antigen was not evident in lymphocyte transformation assays on lymphocytes obtained from Histoplasma-infected guinea pigs or from animals sensitized with complete Freund adjuvant. Fractionation of the antigen was accomplished on an isoelectric-focusing column, using a sucrose density gradient support. Components were assayed for activity in skin testing and lymphocyte transformation. Comparison of column fractions to the whole antigen showed greater response to the whole antigen in in vivo and in vitro assays.

The minimum inhibitory concentrations of a halogenated quinoline, 3-amino-7-chloro-3,4-dihydro-1-hydroxycarbostyril (CBS), against nine clinical strains of Cryptococcus neoformans were determined by in vitro testing. The CBS was fungistatic at a minimum concentration of 0.2 mug/ml at 48 h for several strains. In vivo toxicity studies were carried out in mice. Mice were also infected with C. neoformans strain Price and injected with various concentrations of CBS. Mean life expectancy of treated groups of animals was increased over infected untreated controls.

The action of Merthiolate on the pathogenic yeasts Blastomyces, dermatitidis, Histoplasma capsulatum, and Sporothrix schenckii was compared to the effect of treatment with formaldehyde. Concentrations of 1:10,000 and 1:5,000 Merthiolate for three exposure times (24, 48, and 72 h) at 4 and 25 degrees C were tested on three media (brain heart infusion with and without blood, and modified Sabouraud agar). The effect of Merthiolate on these three yeasts was primarily fungistatic, with maximum effect using 1:5,000 Merthiolate at 25 degrees C for at least 48 h. Mycelial suspensions of B. dermatitidis, H. capsulatum, S. shenckii, and the yeast phase of Cryptococcus neoformans were susceptible to the 1:5,000 Merthiolate concentration after 24 h of treatment. The antifungal effect of Methiolate varies with species and growth phase of the fungus. Concentration, time of exposure, and temperature of incubation are important variables.

Cryptococcus neoformans-infected animals were found to be immunosuppressed when tested by a variety of assays for immune competence. Primary humoral immune responses and delayed-type hypersensitivity reactions to sheep erythrocytes were suppressed in animals which had been infected for two weeks. Lymphocyte proliferation (LP) assays to sRBC stroma were also significantly diminished at two weeks of infection. Spleen cells of infected mice suppressed the LP response of sRBC immunized, normal mice in vitro. At least a part of the suppression could be attributed to a nylon wool non-adherent cell. Suppressor cells continued to be present in spleen cell suspensions following treatment with anti-T cell serum or anti-immunoglobulin and complement. When infected spleen cells were separated by adherence to plastic, both the adherent and non-adherent fractions exhibited suppressive activity. Incubation of infected spleen cells in tissue culture for 48 hr resulted in the elaboration of soluble immunosuppressive factors into the tissue culture medium. These data indicated that immune suppression in cryptococcosis can occur as a result of infection with Cryptococcus neoformans, and that at least one mechanism involved is the induction of adherent and non-adherent suppressor cells in the spleens of infected mice.

Infection with group A streptococci has been implicated as a factor capable of exacerbating psoriasis. In order to explore the possibility of cross-reactivity between streptococcal antigens and human skin in this phenomenon, skin from psoriatic patients and control subjects was reacted with 3 monoclonal antibodies against group A streptococci and antibody binding was estimated by the indirect immunofluorescence technique. Monoclonal antibody 54.2.8 stained the nuclei and cytoplasm of cells within the epidermis and epidermal appendages, as well as cells scattered throughout the dermis. In contrast, monoclonal antibodies 49.8.2 and 36.2.2 labeled the cytoplasm of epidermal cells and epidermal appendages but did not react with nuclei. No difference in the staining patterns of control skin and uninvolved skin from patients with psoriasis was observed. However, skin from psoriatic lesions contained large amounts of cross-reactive skin component(s). Sera from patients with guttate psoriasis did not react differently with normal or psoriatic skin when compared with normal sera. Western immunoblots of skin extracts demonstrated that monoclonal antibody 54.2.8 reacted with a family of proteins in the molecular weight range of 60-70K. The results indicate that component(s) in human skin share cross-reactive epitopes with group A streptococci. Immunologic cross-reactions between group A streptococci and human skin may play an important role in the exacerbation of certain skin disorders following streptococcal infections.

Anti-group A streptococcal monoclonal antibodies were obtained from BALB c/BYJ mice immunized with purified membranes from M type 5 Streptococcus pyogenes. Two of the anti-streptococcal monoclonal antibodies were previously shown to cross-react with muscle myosin. In this study the monoclonal antibodies were reacted with tissue sections of normal human heart and skeletal muscle. Antibody binding was estimated by indirect immunofluorescence and immunoperoxidase techniques. Both of the monoclonal antibodies (36.2.2 and 54.2.8) investigated in this report reacted with heart and/or skeletal muscle sections. When evaluated by immunofluorescence, monoclonal antibody 54.2.8 demarcated the periphery of cardiac striated muscle cells and reacted to a lesser degree with subsarcolemmal components. Monoclonal antibody 36.2.2 failed to react with heart sections, but both of the monoclonal antibodies reacted strongly with skeletal muscle sections. Results similar to those observed with indirect immunofluorescence were obtained with the immunoperoxidase technique. By Western immunoblotting and competitive inhibition assays, monoclonal antibodies 36.2.2 and 54.2.8 both were found to react with the heavy chain of skeletal muscle myosin. However, only 54.2.8 reacted with the heavy chain of cardiac myosin. The specificity of the monoclonal antibodies for subfragments of skeletal muscle myosin indicated that monoclonal antibody 36.2.2 was specific for light meromyosin fragments, whereas 54.2.8 reacted with both heavy and light meromyosin. The data demonstrated that two monoclonal antibodies against streptococci were specific for skeletal muscle and/or cardiac myosin and for subfragments of the myosin molecule. The reactions of the monoclonal antibodies with human tissue sections were consistent with the immunochemical reactions of the monoclonal antibodies with both denatured and native myosin.

Mice were immunized with a viable, avirulent strain of Cryptococcus neoformans. Lymphocyte blastogenic assays showed a 10-fold increase in reactivity of sensitized spleen cells, and histopathologic examination revealed marked splenic hyperplasia. Thirty-two days after intravenous inoculation with a virulent strain of C. neoformans, none of the control animals survived whereas 60 percent of the immunized mice were alive with no clinical evidence of disease. This animal model shows that protective immunity can be established, and once developed, provide a better model for the study of important aspects of immunity in fungal disease.

A murine model was developed to study the cell-mediated immune response of mice immunized with one of two live, avirulent forms of Cryptococcus neoformans: a nonencapsulated mutant and a thinly encapsulated pseudohyphal variant. A lymphocyte transformation assay was used to evaluate the cellular response of control and sensitized spleen cells after in vitro incubation with three merthiolate-killed whole-cell antigens of C. neoformans. An antigen-to-spleen cell ratio of 10:1 and 5 days of incubation of antigen-spleen cell mixtures were established as optimal conditions for maximum lymphocyte transformation. Maximum responses occurred from 2 to 3 weeks after the last of eight weekly intraperitoneal inoculations of C. neoformans. This assay provided an accurate, reproducible method of studying cell-mediated immunity to C. neoformans, and applications to the study of cryptococcal pathogenesis are proposed.