Purified ß-glucans from the Shiitake mushroom ameliorates antibiotic-resistant Klebsiella pneumoniae-induced pulmonary sepsis.

Bacterial infection remains the main cause of acute respiratory distress syndrome and is a leading cause of death and disability in critically ill patients. Here we report on the use of purified ß-glucan (lentinan) extracts from Lentinus edodes (Shiitake) mushroom that can reduce infection by a multidrug-resistant clinical isolate of Klebsiella pneumoniae in a rodent pneumonia model, likely through immunomodulation. Adult male Sprague-Dawley rats were subjected to intra-tracheal administration of K. pneumoniae to induce pulmonary sepsis and randomized to three groups; vehicle control (Vehicle, n = 12), commercial lentinan (CL, n = 8) or in-house extracted lentinan (IHL, n = 8) were administered intravenously 1 h postinfection. Physiological parameters and blood gas analysis were measured, bacterial counts from bronchoalveolar-lavage (BAL) were determined, along with differential staining of white cells and measurement of protein concentration in BAL 48 h after pneumonia induction. Use of IHL extract significantly decreased BAL CFU counts. Both CL and IHL extractions reduced protein concentration in BAL. Use of IHL resulted in an improvement in physiological parameters compared to controls and CL. In conclusion, administration of lentinan to treat sepsis-induced lung injury appears safe and effective and may exert its effects in an immunomodulatory manner.

Studies directed at the use of a parallel synthesis matrix to increase throughput in an in vivo assay.

Heparin is the anticoagulant of choice for hospitalized patients, but it is dosed only by injection because it is not absorbed following oral administration. We have discovered and prepared compounds (delivery agents) that facilitate the gastrointestinal absorption of heparin in rats, monkeys, and humans when given orally. We are currently developing a parallel synthesis approach to increase our delivery agent screening throughput in vivo. This approach has been used to produce micromolar quantities of compounds for testing in rats in a 5 x 5 parallel synthesis array. Using an amine benzoylation reaction sequence, 10 mixtures were prepared. These mixtures contained equal weight quantities of five N-substituted, non-alpha, amino acid delivery agents. Each of these mixtures was orally administered to rats in combination with heparin, and plasma clotting times (APTT) were measured to determine activity. Deconvolution of the data accurately identified the most active individual components. Independent synthesis of these compounds verified their activity. This parallel synthesis approach is an effective tool for the screening of oral heparin delivery agents and has increased screening throughput significantly.

Experimentally induced selenosis of adult mallard ducks: clinical signs, lesions, and toxicology.

Selenosis is thought to be a significant problem among waterfowl populations in selenium-contaminated wetlands in the western United States. Chemical analysis of avian tissues is currently the principal basis for diagnosis. The purpose of these two 150-day studies was to establish whether morphological criteria for selenosis could be developed to supplement chemical analysis. Forty-eight flightling male mallard ducks were fed either a proprietary waterfowl ration (< 1 ppm selenium) or the same ration amended to contain 10, 25, and 60 ppm selenium supplied as seleno-L-methionine (n = 12/group). In a separate study, 12 birds fed twice daily were offered either a proprietary ration or a selenium-supplemented ration (120 microg/g) for one of two daily feedings. Selenium in whole blood increased from baseline concentrations (< 0.4 microg/ml) to means of 4.5, 8.9, and 16.0 microg/ml in the 10-, 25-, and 60-ppm groups, respectively. All birds in the 60-ppm-dose group rapidly lost weight and were killed (11/12) or died (1/12) between 22 and 50 days of dietary exposure. In addition to emaciation, six of 12 birds (50%) fed the 60-microg/g diet developed mild to moderate generalized hepatopathy with single-cell necrosis, karyomegaly of hepatocytes, hyperplastic bile duct epithelium, and/or iron accumulation in Kupffer cells. The principal lesions in birds exposed to other dietary concentrations of selenium involved integumentary structures containing hard keratin. Gross lesions developed after 76 days of dietary exposure and consisted of bilaterally symmetrical alopecia of the scalp and dorsal cervical midline, broken or lost digital nails, and necrosis of the tip of the beak (maxillary nail). One or more of these three lesions were present in 0/12 birds (0%) fed 10 ppm selenium, 5/12 birds (42%) fed 25 ppm selenium, and 4/9 (44%) birds fed a split-feed diet containing 120 ppm selenium. Controls were unaffected. Histologic lesions in digital and maxillary nails consisted of single-cell to full-thickness necrosis of keratinocytes and multifocal parakeratosis in stratum corneum. Histologic lesions in alopecic skin (necrosis of the epidermal collar, inflammation of the feather pulp, and follicular keratosis) were mild. Some birds with alopecia had no detectable lesions in feather follicles from affected areas of skin. The highest tissue concentrations of selenium were in liver, kidney, and feathers, respectively. Mean hepatic tissue concentrations were 14.5 microg/g (10 ppm group), 29.6 microg/g (25 ppm group), 60.6 microg/g (60 ppm group), 13.0 microg/g (120 ppm split-feed group), and 2.0 microg/g (controls). Integumentary and hepatic lesions may be of value in corroborating a diagnosis of selenosis based on chemical analysis of tissues from naturally intoxicated waterfowl. Some birds with fatal selenosis may have no morphologic lesions other than emaciation.

Toxicologic evaluation of a high-selenium hay diet in captive pronghorn antelope (Antilocapra americana).

Five captive-raised pronghorn antelope (Antilocapra americana) were fed an alfalfa-grass hay diet containing 15 ppm total dietary selenium (Se) for 164 days. Four additional captive-raised pronghorns fed a similar diet containing approximately 0.3 ppm total dietary Se served as controls. None of the pronghorns had clinical signs attributable to the high Se hay. Plasma Se increased more rapidly than blood Se concentrations, from baseline concentrations (< 0.15 g/ml) to > 0.40 g/ml within the first 50 days on the high selenium diet, but thereafter declined to approximately 0.30 microgram/ml. Mean primary antibody response to hen egg albumin was less in pronghorn on Se hay. No significant gross or histological lesions attributable to selenosis were found, nor was there any evidence of dystrophic hoof growth. The greatest Se tissue concentrations were found in liver and kidney (5.67 to 10.4 micrograms/g and 2.36 to 3.14 micrograms/g, respectively) from experimental animals; liver and kidney from the controls contained considerably less (< or = 0.52 microgram/g and < or = 0.61 microgram/g, respectively). Exposure of pronghorns for more than 5 mo to a diet containing 15 ppm Se caused significant increases in plasma, liver and kidney Se concentrations, in the absence of clinical disease or pathologic lesions due to selenosis. Based on these results, we propose that pronghorns are less susceptible to selenosis than previously reported and that diagnostic criteria for the disease should be modified.

Pathology of experimentally induced chronic selenosis (alkali disease) in yearling cattle.

Prolonged oral exposure of cattle to elevated dietary selenium (Se) in forage and seleniferous plants in seleniferous areas of the western United States is associated historically with 2 clinical syndromes: alkali disease and "blind staggers." The potential for Se-induced disease in cattle and other species is considerable in areas with seleniferous shales, Se-accumulating plants, arid climates, and alkaline soils. These 2 Se-associated conditions were defined in the 1930s and 1940s, and the nosology of blind staggers is questionable. Seventeen yearling steers fed 0.15, 0.28, and 0.8 mg Se/kg body weight as selenomethionine or selenite for 120 days were euthanized and examined postmortem. Significant lesions were confined to 4 steers in the medium- and high-dose selenomethionine group and to 1 steer in the high-dose selenite group. Grossly, dystrophic hoof lesions developed in 2 steers, 1 of which had extensive separation of horn from lamellar and coronary epidermis and also lost hair from the tail switch. Histologically, tubules in the stratum medium of hooves from these 5 steers were replaced by islands of parakeratotic cellular debris, separated by more normal hoof matrix. Two of the 5 steers also had hyperplasia, acanthosis, parakeratosis, and disorganized germinal epithelium of varying severity in hoof epithelium, particularly at the tips of epidermal lamellae. These changes may distinguish the hoof lesions of chronic selenosis from those of chronic laminitis in cattle, in which dermal (chorial) changes predominate. In skin from the distal part of the tail of the animal that lost its switch, most follicles were atrophic and devoid of hairshafts and displayed dyskeratosis and mild superficial follicular keratosis. No significant lesions developed in tissues other than integument. Autometallographic staining for catalytic Se bonds in various tissues, including skin, liver, and kidney, revealed no positive staining of hair shafts; the correlation between stain intensity and dose group was poor. These findings indicate that dietary exposure for 4 months to 0.28 and 0.8 mg Se/kg in the form of selenomethionine and to 0.8 mg Se/kg in the form of sodium selenite reproduces in some cattle mild (subclinical) to severe (clinical) forms of alkali disease. No significant neurological, renal, or hepatic lesions developed, supporting the contention that blind staggers is caused by factors other than excessive dietary selenium.

Naturally occurring selenosis in Wyoming.

A review of Wyoming State Veterinary Laboratory records for 1947-1987 revealed no substantiated cases of naturally occurring selenosis. However, older reports attributed thousands of animal deaths to selenium each year in this area. Beginning in August 1988, cases of suspected selenosis and selenium deficiency were solicited from veterinarians and producers by announcements in various statewide livestock publications. As of August 1991, 4 cases (all horses) of naturally occurring selenosis have been confirmed. Clinical signs were most often referable to epithelial damage, e.g., hoof lesions and loss of mane and tail. None involved neurologic signs. Sources of selenium included native range and grass hay.

Chronic myofascial pain: management by low-output helium-neon laser therapy.

Therapeutic benefits of low-output helium-neon laser therapy have not been established, but laser therapy has been suggested as an effective means of treating many acute and chronic musculoskeletal pain syndromes. Although not released for general clinical use by the FA, the helium-neon laser has been promoted to physical therapists and athletic trainers as potentially useful for the treatment of pain syndromes. In particular, it has been proposed that it may be more effective than conventional measures such as medication and conventional physical therapy in the treatment of myofascial pain syndromes (fibrositis, fibromyalgia). The citations in the literature include only case reports. Sixty-two patients were treated by using acupuncture points. Two sessions of five treatments were given six weeks apart. A crossover double-blind technique was used in the treatments. The clinical responses were assessed using portions of the McGill Pain Questionnaire. No statistical difference between the treatment and the placebo groups could be determined.

Social-skills training to teach alcoholics to refuse drinks effectively.

Two alcoholics who received social-skills training in ways of refusing drinks reported some success in applying their new skills in actual social situations after they left the hospital.