A genetic screen to uncover mechanisms underlying lipid transfer protein function at membrane contact sites

Lipid transfer proteins mediate the transfer of lipids between organelle membranes, and the loss of function of these proteins has been linked to neurodegeneration. However, the mechanism by which loss of lipid transfer activity leads to neurodegeneration is not understood. In Drosophila photoreceptors, depletion of retinal degeneration B (RDGB), a phosphatidylinositol transfer protein, leads to defective phototransduction and retinal degeneration, but the mechanism by which loss of this activity leads to retinal degeneration is not understood. RDGB is localized to membrane contact sites through the interaction of its FFAT motif with the ER integral protein VAP. To identify regulators of RDGB function in vivo, we depleted more than 300 VAP-interacting proteins and identified a set of 52 suppressors of rdgB The molecular identity of these suppressors indicates a role of novel lipids in regulating RDGB function and of transcriptional and ubiquitination processes in mediating retinal degeneration in rdgB9 The human homologs of several of these molecules have been implicated in neurodevelopmental diseases underscoring the importance of VAP-mediated processes in these disorders.

Effects of a water-soluble extract of maitake mushroom on circulating glucose/insulin concentrations in KK mice

AIM

We examined benefits of a water-soluble extract of maitake mushroom designated as Fraction X (FXM) on the glucose/insulin metabolism of insulin-resistant KK mice, and compared the results of FXM with those of a sulphonylurea, Glipizide.

DESIGN

In several acute studies, insulin-resistant KK mice were gavaged with a single dose of varying concentrations of FXM, or a single dose of one concentration of the oral hypoglycaemic drug, Glipizide. In the one chronic study, KK mice were gavaged with FXM, Glipizide, or an equal volume of isotonic saline (baseline control) twice daily. Retro-orbital blood was drawn on the morning of the 4th and 7th days before the early gavage. Blood glucose was measured by routine laboratory procedures, and serum insulin was estimated by a radioimmunoassay (RIA) assay developed specifically for rodents.

RESULTS

At a dose of FXM (140 mg/mouse), a statistically significant lowering of circulating glucose concentrations was again seen at 8-12 h and 16-18 h after oral gavage. The lowering approximated 25% of the original concentration. Oral gavage of Glipizide resulted in statistically significantly lower values of circulating glucose (25-37% lower compared with baseline) at 8-24 h post dosing. In the chronic study, the circulating concentrations of glucose and insulin of mice taking 140 mg FXM per day were decreased significantly at days 4 and 7.

CONCLUSIONS

FXM, a natural extract obtained from maitake mushroom, favourably influences glucose/insulin metabolism in insulin-resistant KK mice. The lowering of both circulating glucose and insulin concentrations suggests that FXM works primarily by enhancing peripheral insulin sensitivity.

Antifungal activities of origanum oil against Candida albicans

The antimicrobial properties of volatile aromatic oils from medicinal as well as other edible plants has been recognized since antiquity. Origanum oil, which is used as a food flavoring agent, possesses a broad spectrum of in vitro antimicrobial activities attributed to the high content of phenolic derivatives such as carvacrol and thymol. In the present study, antifungal properties of origanum oil were examined both in vitro and in vivo. Using Candida albicans in broth cultures and a micro dilution method, comparative efficacy of origanum oil, carvacrol, nystatin and amphotericin B were examined in vitro. Origanum oil at 0.25 mg/ml was found to completely inhibit the growth of C. albicans in culture. Growth inhibitions of 75% and >50% were observed at 0.125 mg/ml and 0.0625 mg/ml level, respectively. In addition, both the germination and the mycelial growth of C. albicans were found to be inhibited by origanum oil and carvacrol in a dose-dependent manner. Furthermore, the therapeutic efficacy of origanum oil was examined in an experimental murine systemic candidiasis model. Groups of mice (n = 6) infected with C. albicans (5 x LD50) were fed varying amounts of origanum oil in a final vol. of 0.1 ml of olive oil (vehicle). The daily administration of 8.6 mg of origanum oil in 100 microl of olive oil/kg body weight for 30 days resulted in 80% survivability, with no renal burden of C. albicans as opposed to the group of mice fed olive oil alone, who died within 10 days. Similar results were obtained with carvacrol. However, mice fed origanum oil exhibited cosmetically better clinical appearance compared to those cured with carvacrol. The results from our study encourage examination of the efficacy of origanum oil in other forms of systemic and superficial fungal infections and exploration of its broad spectrum effect against other pathogenic manifestations including malignancy.

Ameloblastic carcinoma. A case report with review of literature

Ameloblastic carcinoma is a rare odontogenic malignant tumour and has been a subject of great debate in literature. It does challenge the diagnostic acumen of pathologists, as this lesion needs to be detected at an early stage for adequate therapy. We present a case of the same with literature review.

Influence of a combination of herbs on appetite suppression and weight loss in rats

AIM

We evaluated the ability of a Chinese herbal formulation previously associated with weight loss to influence appetite and weight loss in a carefully controlled laboratory study performed on rats. As a secondary gain, results with this herbal formulation were compared with those from a commonly available phenylpropanolamine (PPA) compound.

DESIGN

Eight rats were placed in each arm of a three-arm study, a total of 24 rats. All rats were gavaged with a 2-ml fluid volume containing no addition (control) or the two test substances (combined herbs or PPA) for the first 4 days of the week over 6 consecutive weeks; no gavages were given over weekends. Rats in the two-test groups were given a relatively low dose of the test substance for 3 weeks, followed by a higher dose over the next 3-week periods. Food and water intake were measured for 24-h periods over the ensuing week days. The average daily values for food and water intake for an individual rat were calculated on the basis of collected data over each 3-week period. The mean values for each rat obtained over the low- and high-dose periods comprised results from averaging at least 10 measurements.

RESULTS

Average daily food intake was decreased only with the herbal formulation, not the PPA compound at the low and high doses. Both the PPA compound and the herbal formulation lowered water intake significantly at the low and high doses. Rats ingesting the herbal formulation at the lower dose had statistically significant lower daily body weight changes over the 3 weeks than those ingesting the PPA compound. At the higher dose, body weight changes for both agents were significantly less than the control, but not significantly different from each other. No evidence of toxicity was seen in the blood chemistries or after histopathological examination.

CONCLUSIONS

Data collected on rats suggest that the herbal formulation examined might be a useful and safe combination to overcome the overweight state and obesity.

Murine splenic hematopoietic subpopulations: the enlarged undifferentiated subset in New Zealand black mice is multipotent stem cells

We recently reported that a significant population of the murine splenic non-T, non-B "null" cell compartment consists of non-lineage-specific, undifferentiated cells which are in the G0 and G1 phases of the cell cycle and that their numbers are particularly high in the spleens of New Zealand Black mice. A highly enriched population of these non-lineage-specific cells obtained by successive elimination of differentiated cells was further purified to homogeneity by fluorescence-activated cell sorting. The morphologic, phenotypic, and histochemical characteristics of this purified population suggest that these cells may be primitive hematopoietic stem cells. The germ line configuration of the genomic DNA establishes that these are uncommitted stem cells. In vivo, these cells form day 12 colonies in the spleen and liver of lethally irradiated recipients and confer radioprotection. These cells also differentiate into T- and B-cell lineages and reconstitute the immunodeficiency in mice with severe combined immunodeficiency. In response to a combination of a very few early-acting lymphokines and/or stromal cell-conditioned medium in vitro, these cells differentiate into both myeloid and lymphoid cell types. More of these cells are obtained from the enlarged spleens of New Zealand Black mice than from those of BALB/c mice. The presence of a comparatively higher number of stem cells in the spleen than in the marrow or fetal liver provides an alternative, and possibly superior, source of uncommitted stem cells for a variety of experimental investigations or therapeutic manipulations.

Murine splenic null cell compartment contains distinct haemopoietic subpopulations: enlargement of a myeloid and an undifferentiated subset with the development of splenomegaly in New Zealand black mice

We have previously reported that non-T, non-B 'null' cells increase with age in New Zealand Black (NZB) mice resulting in splenomegaly. Using a panel of monoclonal antibodies recognizing lineage-specific cell surface antigens we demonstrate four distinct subsets within this null cell compartment: (1) undifferentiated; (2) T lineage with undetectable Thy-1.2; (3) myeloid/erythroid; and (4) a pre-B/plasma cell type. All four subsets also occur in non-autoimmune mice. The frequency of these populations are similar in the young mice of all the strains examined, although the total number of null cells is higher in NZB. The elevation of null cells in young NZB mice is controlled by a single dominant gene in the genetic cross with New Zealand White (NZW) mice and does not appear closely related to the subsequent development of autoimmune disease. The proportion of myeloid/erythroid null cells increases with age in NZB as splenomegaly develops.

Proliferation of infected lymphoid precursors before Moloney murine leukemia virus-induced T-cell lymphoma

NFS/N mice inoculated with Moloney murine leukemia virus (M-MuLV) developed T-cell lymphoma after a 10-week latent period. Expression of lymphoid differentiation antigens, appearance of M-MuLV-encoded cell surface antigens, and rates of cellular proliferation were measured in splenic and bone marrow subpopulations during this latent period. At 2 weeks of age, Thy-1-and surface immunoglobulin-negative null cells of spleen and bone marrow expressed M-MuLV antigens whereas T- and B-lymphocytes did not. During the 3d and 4th weeks, the number of splenic null cells increased to six times the number found in uninfected controls. These null cells included the precursors of lymphocytes and hematopoietic cells. For the remainder of the latent period, the percentage of null cells undergoing proliferation was three times greater in the infected mice, while the total number of null cells remained constant. This proliferation was not accompanied by terminal differentiation or emigration of mature cell types from the spleen. Proliferation was substantially delayed in CBA mice, which are resistant to lymphoma induction.

Ly-2+ T cell enlargement and null cell proliferation occur at the onset of splenomegaly and autoantibody production in New Zealand Black mice

Splenic T and B lymphocyte and null cell populations were analyzed in NZB mice as autoimmune disease developed during the first year of life. In the B lymphocytes, a progressive shift occurred from the surface IgD bright subset to the surface IgM bright subset. There was a slight increase in the ratio of Ly-2- to Ly-2+ T cells. Splenomegaly was not detected until after 40 wk of age and was primarily due to an increase in the number of null cells. This change was accompanied by an increase in the size, as determined by narrow-angle forward light scatter, of the Ly-2+ but not the Ly-2- T cells, an elevation of IgG-containing plasma cells, and the appearance of anti-erythrocyte autoantibody. The splenic B cell subset distribution and the enlargement of the Ly-2+ T cells were reflected in the peripheral blood, whereas the T cell subset ratio was not. The B cell subset alteration did not correlate with any of the other changes observed. Statistical associations were found between the ratios of T cell subsets, the enlargement of the Ly-2+ T cells, and the increased number of null cells, suggesting a linkage among those late changes that immediately precede the development of overt autoimmune disease.

Ly-2+ T cell enlargement and null cell proliferation occur at the onset of splenomegaly and autoantibody production in New Zealand Black mice

Splenic T and B lymphocyte and null cell populations were analyzed in NZB mice as autoimmune disease developed during the first year of life. In the B lymphocytes, a progressive shift occurred from the surface IgD bright subset to the surface IgM bright subset. There was a slight increase in the ratio of Ly-2- to Ly-2+ T cells. Splenomegaly was not detected until after 40 wk of age and was primarily due to an increase in the number of null cells. This change was accompanied by an increase in the size, as determined by narrow-angle forward light scatter, of the Ly-2+ but not the Ly-2- T cells, an elevation of IgG-containing plasma cells, and the appearance of anti-erythrocyte autoantibody. The splenic B cell subset distribution and the enlargement of the Ly-2+ T cells were reflected in the peripheral blood, whereas the T cell subset ratio was not. The B cell subset alteration did not correlate with any of the other changes observed. Statistical associations were found between the ratios of T cell subsets, the enlargement of the Ly-2+ T cells, and the increased number of null cells, suggesting a linkage among those late changes that immediately precede the development of overt autoimmune disease.

A flexible cystoscope

An assessment of the prototype Olympus Flexible Cystoscope in routine urological practice is presented. The results show that the instrument compares favourably in all respects with standard rigid equipment and has the advantage that cystoscopy can be performed supine and under local anaesthesia with ease. Biopsies may be taken; small lesions fulgurised and ureteric catheterisation can be performed without general anaesthesia.

Expression of Lyt-1 by a subset of B lymphocytes

Using two-color flow cytometry and multiparameter data analysis, we have shown that the IgM bright, large subset of mouse splenic B lymphocytes express Lyt-1. This is not due to B cell uptake of immune complexes of Lyt-1 and antibody from T cells. The IgM bright cells of autoimmune NZB mice express more Lyt-1 than normal controls. This is because IgM containing plasmablasts, which are greatly increased in NZB spleens, are Lyt-1+. NZB spleen also contains more cells that are Lyt-1+ (but perhaps Lyt-1.2-), Thy-1.2 dull, and smaller in size than cells in normal mice. Thus, Lyt-1 is common to the T and B cell precursor or is induced independently during the ontogeny of T and at least one subset of B cells. We suggest that it be called Lyt-1.

Expression of Lyt-1 by a subset of B lymphocytes

Using two-color flow cytometry and multiparameter data analysis, we have shown that the IgM bright, large subset of mouse splenic B lymphocytes express Lyt-1. This is not due to B cell uptake of immune complexes of Lyt-1 and antibody from T cells. The IgM bright cells of autoimmune NZB mice express more Lyt-1 than normal controls. This is because IgM containing plasmablasts, which are greatly increased in NZB spleens, are Lyt-1+. NZB spleen also contains more cells that are Lyt-1+ (but perhaps Lyt-1.2-), Thy-1.2 dull, and smaller in size than cells in normal mice. Thus, Lyt-1 is common to the T and B cell precursor or is induced independently during the ontogeny of T and at least one subset of B cells. We suggest that it be called Lyt-1.

Immunoprophylaxis of transplantable methylcholanthrene-induced murine fibrosarcomas by immunization with embryo cells expressing endogenous murine leukemia virus antigens

We investigated the nature of a common tumor rejection antigen(s) in chemically induced murine fibrosarcomas. Two methylcholanthrene-induced fibrosarcomas, previously demonstrated to contain a common tumor rejection antigen(s), released infectious ecotropic murine leukemia virus and expressed the murine leukemia virus proteins, a glycoprotein with a molecular weight of 70,000 (gp70) and an envelope protein with a molecular weight of 15,000. To determine whether an antigen(s) specified by a murine leukemia virus might serve as a common tumor rejection antigen(s), primary cultures of syngeneic embryo cells or cultures of an allogeneic embryo cell line were infected with an endogenous ecotropic murine leukemia virus obtained from one of the cross-reacting fibrosarcomas; expression of infectious virus and/or viral proteins by infected and uninfected embryo cells was monitored and correlated with the results of transplantation protection tests. Uninfected allogeneic embryo cells (SC-1) did not release infectious virus or the viral protein gp70; mice immunized with SC-1 cells did not inhibit tumor growth. Uninfected syngeneic embryo cells did not release infectious virus but did release micrograms quantities of gp70 into supernatant fluids; mice immunized with uninfected syngeneic cells inhibited tumor growth in two of seven experiments. Virus-infected syngeneic and allogeneic embryo cells released both infectious ecotropic murine leukemia virus and gp70; mice immunized with virus-infected cells inhibited tumor growth in 11 of 11 experiments. Growth of the two cross-reacting fibrosarcomas was inhibited in mice immunized with virus-infected embryo cells. The results indicate that antigens coded for by endogenous murine leukemia virus may function as common tumor rejection antigen on chemically induced murine fibrosarcomas.

The impact of training on career mobility of alcoholism counselors. A follow-up study

Graduates of a training program for alcoholism counselors were more likely to remain in the field of alcoholism treatment than were rejected applicants, but the training did not enhance their career satisfaction and advancement.

Evaluation of training of alcoholism counselors

During a 14-month training program for paraprofessional alcoholism counselors some counselors were markedly more successful than others in keeping patients in treatment and these differences persisted over time.

Miconazole in the treatment of superficial mycoses

Miconazole nitrate (2%) cream was evaluated in the treatment of superficial mycoses. Out of 116 patients having multiple clinical diagnoses, 66 cases were found to be positive by culture. Species of Trichophyton were the predominant etiological agents (in over 60%) followed by Candida species (20%) and Epidermophyton floccosum (15%). All the cases selected for study were followed up to a period of 4-18 months. A cure rate of 94.6 per cent was observed in all the cases where causal organisms were isolated. Significantly high cure rate (66%) was also seen in cases where causal organisms could not be isolated, including cases of tinea versicolor. Results of mycological examination were in confirmity with the clinical results.

Antidermatophytic activity of 2-thiotetrahydro-1,3,5-thiadiazines and isothiocyanates

Benzyl, furfuryl, tetrahydronaphthyl, alpha-picolyl, and alpha-homopicolyl derivatives of 2-thiotetrahydro-1,3,5-thiadiazines were studied and found to be more active than beta-picolyl, and pyridyl analogs on dermatophytes, including the more resistant Microsporum canis.