Overcoming limitations in elbow movement in the presence of antagonist hyperactivity

BACKGROUND AND PURPOSE

A traditional perspective on rehabilitation of patients with abnormal muscular hyperactivity presumes that relaxation should be facilitated prior to recruitment of antagonists, if effective movement about a joint is to occur. The purpose of the study was to determine the effect of training weak triceps brachii muscles, with hyperactivity present in the opposing biceps brachii muscles, on elbow function in individuals at least 1 year poststroke.

SUBJECTS

Sixteen patients with chronic stroke were randomly assigned to receive electromyographic biofeedback to retrain the triceps muscle (n = 8) or to receive conventional movement training (n = 8).

METHODS

Both groups participated in 5 baseline and 10 training sessions involving tasks requiring elbow extension. Preintervention and postintervention measurements included elbow extension range of motion, triceps and biceps muscle electromyographic activity during performance of elbow extension, resisted elbow extension, and a reaching task.

RESULTS

Two-sample t-test results of between-group comparisons for each variable were not significant. One-sample t-test results of within-group comparisons showed significant increases in triceps muscle mean electromyographic activity during two of the three tasks for the feedback group, but not for the nonfeedback group. Passive and active range of motion in both groups increased significantly, although biceps muscle co-contraction persisted.

CONCLUSION AND DISCUSSION

These results suggest that functional improvements at the elbow may have been due to biomechanical (peripheral) rather than neuromuscular (central) changes about the joint. Furthermore, these preliminary data indicate that patients with stroke may be trained to increase movement without first being trained to specifically inhibit hyperactivity in muscles.

Inhibition of sialyl transferase activity by gossypol acetic acid in human seminal plasma

Seventeen aliquots of 15 microliters seminal plasma of human origin were incubated with 25 micrograms, 15 micrograms, 5 micrograms and 2.5 micrograms gossypol acetic acid (GAA), dissolved in BWW containing 0.9% sodium chloride and 0.9% benzyl alcohol, at 37 degrees C for 60 minutes. Following incubation, activity of sialyl transferase (S.T.) was determined by a procedure involving incorporation of radioactive sialic acid into asialofetuin. The activity of S.T., expressed as cpm per hour per 15 microliters seminal plasma was compared to controls consisting in incubation of sperm in BWW containing 0.9% benzyl alcohol and 0.9% sodium chloride. The activity of S.T. in controls represented 61.3 +/- 8.0%-67.7 +/- 8.9% of the activity obtained by incubation with BWW only. GAA was found to exert a dose-dependent inhibition of S.T. activity, ranging from 38.3 +/- 20.6% to 53.4 +/- 19.4% (with 25 micrograms) and from 11.3 +/- 14.8% to 21.9 +/- 14.8% (with 2.5 micrograms).

Sialyltransferase activity in AF10 myeloma cell line

A STA was observed in a human-derived myeloma cell line, AF10, that produces IgE paraprotein. The STA in the culture medium of the AF10 myeloma cell line was associated in the 24 to 48 hr period of incubation with IgE biosynthesis, and increased thereafter up to 72 hr, while IgE remained stable. These data support our previous observations that human myeloma cells are associated with a relatively high production of sialyltransferase, which is released to the medium, presumably by a mechanism of shedding.

Sialyltransferase activity in plasma cells of multiple myeloma

A marked elevation of sialyltransferase activity (STA) was observed in a solid tumor of plasma cells, which had been removed from a patient with multiple myeloma (MM), as compared to normal lymphatic tissues. STA was also determined in mononuclear bone marrow cells of 10 patients with MM and found to be 12 times higher than that of bone marrow mononuclear cells from 5 patients with non-malignant disorders (with less than 1% plasma cells in the bone marrow aspirate). A significant correlation was found between STA and the number of plasma cells in the bone marrow aspirate.

Candidal vaginitis in hormone-treated mice: prevention by a chitin extract

In view of findings from previous studies that a chitin soluble extract (CSE) blocked adhesion of Candida albicans in vitro and in vivo and prevented thereby a short lived candidal infection in naive mice, we attempted in the present study to block by CSE the development of a persistent infection, induced in hormone-treated animals. Continuous oestrus phase was obtained in mice by repeated weekly subcutaneous injections with estradiol benzoate. Intravaginal inoculation of the hormone-treated mice with 10(7)-10(10) C. albicans cells induced a persistent candidal infection. Fifty three mice were pretreated intravaginally prior to inoculation of C. albicans with 2.5, 5.0 or 10 mg/mouse of a CSE cream and followed up for development of infection in comparison to 30 untreated animals. Twenty four hrs post fungus inoculation the infection rate among the CSE treated mice was 11-23% VS 84% among the controls; the rate increased a week later to 97% among the controls VS 41-50% among the CSE treated. Administering the CSE to the mice prior--and post-yeast inoculation (37 mice), led to increased efficacy of the treatment. The data, indicating that CSE is an effective measure for preventing persistent candidal vaginitis, may open the way to consider a similar approach for prophylaxis of vaginitis in human susceptible populations.

Effect of Candida albicans cell wall components on the adhesion of the fungus to human and murine vaginal mucosa

In this study, cell walls from Candida albicans were separated and chitin was isolated from these cell walls. A chitin soluble extract (CSE) prepared from the chitin inhibited in vitro adhesion of C. albicans to human epithelial vaginal cells (VEC), and blocked in vivo attachment to murine vaginal mucosa, thereby preventing candidal infection in these animals. These findings suggest that the CSE acts as an adhesin-like substance. Fractionation of CSE yielded two fractions: FI and FII, of which only FI exhibited inhibitory activity. Chemical analysis of CSE and its two fractions revealed that CSE contains over 70% of proteins, most of which were found in the non-active fraction. In addition, 3% of amino-sugars were found in the FI active fraction. Lipids were also detected in the unfractionated CSE and in both fractions. Experiments to further characterize the component(s) in the CSE inhibiting the attachment of C. albicans are in progress in our laboratory.

Pathogenesis of vaginal candidiasis: studies with a mutant which has reduced ability to adhere in vitro

A spontaneous, cerulenin-resistant mutant of Candida albicans (strain 4918-10) was found to adhere less readily to human vaginal mucosal cells in vitro than a wild type C. albicans (strain 4918). In a murine model of vaginal infection, strain 4918-10 was found to be less virulent than wild type C. albicans, i.e., the infection rate caused by 4918-10 was only 31% of that observed with wild type, 4918. A chitin-soluble extract (CSE) prepared from 4918 blocked attachment of yeast cells to human vaginal epithelial cells, while CSE from 4918-10 did not significantly reduce the attachment of yeasts to vaginal cells. Both 4918 and 4918-10 produced hyphae in vitro and in vivo, were negative for proteinase production and grew equally well at 28 degrees C and 37 degrees C. The data suggest that adherence to vaginal mucosa may be an important determinant in the pathogenesis of vaginal infection caused by C. albicans.

Adherence of Candida albicans to buccal and vaginal epithelial cells: ultrastructural observations

The adherence of Candida albicans to human buccal and vaginal epithelial cells was studied by transmission electron microscopy. Adherence to epithelial cells was confirmed by both a radiometric assay as well as direct microscopic examination of stained cell preparations. Ultramicroscopic preparations revealed that yeast cells were closely appressed to epithelial cell surfaces and were often partially enclosed within phagocyticlike invaginations of the epithelial cells. A murine model of vaginitis caused by C. albicans was also used to study adherence to epithelial cells and to follow the course of colonization. Ultramicroscopic preparations of murine vaginal tissue revealed that within 2 h postinfection, yeast cells could be seen adhering to epithelial cells. At 6 h postinfection, hyphae and yeast cells were not only found on the epithelial cell surface but also within the submucosal tissue. When observed on the epithelial cell surface, Candida cells were either attached to host cells, or when infected tissue was stained with ruthenium red, Candida cells were observed on the epithelial surface embedded within an electron-dense matrix. Fungal elements were abundant in the submucosa at 24 h postinfection and were still observed on the epithelial cell surface; all of this was accompanied by an inflammatory response.

Attachment of Candida to mammalian tissues--clinical and experimental studies

In this study we investigated whether a correlation between the frequency of candidal vaginitis and in vitro adherence of Candida albicans to human vaginal epithelial cells exists. The in vitro adherence of C. albicans to epithelial cells collected from 347 women of fertility and postmenopausal age, who did not suffer from vaginitis was assessed microscopically. Epithelial cells from women of the groups with known high frequency of vaginitis: diabetic and pregnant women revealed increased ability of in vitro adherence in comparison with a control group. We also investigated whether a correlation between the hormonal status of the women and adherence capacity of the epithelial cells exists. In vivo attachment of C. albicans to epithelial cells was studied in an experimental murine vaginitis model and assessed histopathologically in tissue sections or microscopically in mounts of exfoliated cells. Attempts were made to block the in vivo attachment and prevent infection by pretreating the animals with substances analogous to the fungal cell walls: substances which were previously found to be inhibitory in the in vitro adherence assay. Chitin, its component - N-acetylglucosamine (NAG) and a soluble extract derived from chitin (CSE) inhibited in vivo attachment and prevented infection.

In vitro and in vivo adherence of Candida albicans to mucosal surfaces

In continuation of a previous study, chitin soluble extract (CSE) and anti-Candida albicans antibodies were found to inhibit the in vitro adherence of C. albicans to human vaginal epithelial cells by 60-70%. Pretreatment of epithelial cells with chitin, CSE or N-acetyl-glucosamine (NAG) decreased the percentage of adherence, while pretreatment of yeasts had no such effect, indicating that chitin or its derivatives may be involved in mediating the adherence of C. albicans. In vivo attachment of C. albicans to epithelial cells was studied in an experimental murine vaginitis created by inoculating mice intravaginally with yeasts at the oestrus stage. Attachment of the yeasts to exfoliated vaginal epithelial cells was followed microscopically, and the course of infection was assessed histopathologically in tissue sections at various times post-yeast inoculation. The infection rate at 24-h post-yeast inoculation was approximately 50%. Attempts were made to block in vivo attachment and prevent infection by pretreating 208 mice with either CSE, NAG, mannan or phosphate-buffered saline (PBS) prior to inoculation with yeasts. The infection rate among mice pretreated with mannan or PBS was 41.6% and 43.8%, respectively. Among CSE- or NAG-pretreated animals, the rate ranged from 0-9%. Treatment of mice with CSE or NAG after inoculation of the yeasts did not prevent infection. The data from the in vivo experiments reveal that pretreatment of animals with chitin derivatives blocks attachment of yeasts to the vaginal mucosal surfaces and leads to the prevention of vaginal infection in an experimental model.

Adherence of Candida albicans to human vaginal epithelial cells: inhibition by amino sugars

In vitro adherence of Candida albicans to human vaginal epithelial cells was studied, aimed at identifying the surface components involved in this binding. The inhibitory effect of yeast cell wall components and their constituents on the adherence of yeasts to epithelial cells was tested. Only chitin, its hydrolysate derivative and N-acetylglucosamine, the constituent of chitin, acted as inhibitors. Binding was also inhibited by the amino sugars glucosamine and mannosamine, while none of the other sugars tested (methylated or nonmethylated) exhibited such an effect. These data suggest that the amino groups of sugars are responsible for the inhibition of adherence of this eucaryotic microorganism to epithelial cells.

Exogenous mycotic infections of the eye and adnexia

Three cases of exogenous mycotic infections of the eye are presented. The first is a case of keratitis in a patient suffering from glaucoma simplex who removed a foreign body from the cornea, caused by Fusarium solani, generally known as a saprophytic soil and plant inhabitant. As factors predisposing the patient to infection, trauma to the cornea like injury by a foreign body, as well as the preexisting disease of the eye, are discussed. The other case illustrates the change in the pathogenicity of an otherwise innocent fungus like Penicillium, which penetrated the sclera after injury of the eye by a broken airpiece of a drill and caused a severe endophathalmitis. The infection responded well to treatment with 5-fluorocytosine. The last case represents a rather mild well-known mycotic infection by Streptomyces somaliensis causing canaliculitis in a patient admitted for cataract surgery. Curettage of the infected canaliculus followed by iodine washout proved to be effective. The importance of the early clinical and laboratory diagnosis in order to avoid mistreatment with antibiotics and steroids and to ensure the right antimycotic treatment is stressed.

The isolation of keratinophilic fungi from soils in Israel. A preliminary report

One hundred and fourteen soil samples collected from various areas of Israel were screened for the presence of keratinophilic fungi. Five species were isolated from the 59 positive samples, viz: C. keratinophilum--22 strains, C. evolceanui--18, C. serratus Eidam--10, M. gypseum--T. terrestre--4. Most of the geophilic organisms were recovered from garden soil, road-side and sandy-soil specimens. The importance of these findings is briefly discussed.

Saprophytic occurrence of Trichophyton mentagrophytes and Microsporum gypseum in the coats of healthy laboratory animals. (Preliminary report)

A group of 199 healthy laboratory animals, comprising 63 guinea pigs; 58 white mice. 47 rats and 31 rabbits, was sampled for the presence of pathogenic dermatophytes. T. mentagrophytes, var. granulare, was isolated in 10% (5-guinea pigs, 6 mice, 6 rats and 2 rabbits) and M. gypseum was found in 7 animals (3 guinea pigs, 3 mice and one rat). No ringworm lesions were observed in the respective animals. This is the first report on such findings in Israel.