Differential expression of mammalian TRP homologues across tissues and cell lines

Mammalian homologues of the Drosophila trp gene have been invoked as the structural basis for the currents associated with capacitative Ca2+ entry (CCE) in many cell types. Trp homologues are members of a large protein family that may associate as channel subunits providing an explanation for the functional diversity of store-operated channels observed in these cells. However, there is little information as to which of these genes are co-expressed at the cellular level. We have examined the tissue specific expression of five mammalian trp genes and determined which are co-expressed in five different cell lines. The results show tissue- and cell-specific co-expression of multiple trp forms. This implies that the subunit composition of a particular CCE channel may vary depending on the cell type.     

Genetic mapping of a major susceptibility locus for juvenile myoclonic epilepsy on chromosome 15q

The epilepsies are a group of disorders characterised by recurrent seizures caused by episodes of abnormal neuronal hyperexcitability involving the brain. Up to 60 million people are affected worldwide and genetic factors may contribute to the aetiology in up to 40% of patients. The most common human genetic epilepsies display a complex pattern of inheritance. These are categorised as idiopathic in the absence of detectable structural or metabolic abnormalities. Juvenile myoclonic epilepsy (JME) is a distinctive and common variety of familial idiopathic generalised epilepsy (IGE) with a prevalence of 0.5-1.0 per 1000 and a ratio of sibling risk to population prevalence (lambda(s)) of 42. The molecular genetic basis of these familial idiopathic epilepsies is entirely unknown, but a mutation in the gene CHRNA4, encoding the alpha4 subunit of the neuronal nicotinic acetylcholine receptor (nAChR), was recently identified in a rare Mendelian variety of idiopathic epilepsy. Chromosomal regions harbouring genes for nAChR subunits were therefore tested for linkage to the JME trait in 34 pedigrees. Significant evidence for linkage with heterogeneity was found to polymorphic loci encompassing the region in which the gene encoding the alpha7 subunit of nAChR (CHRNA7) maps on chromosome 15q14 (HLOD = 4.4 at alpha = 0.65; Z(all) = 2.94, P = 0.0005). This major locus contributes to genetic susceptibility to JME in a majority of the families studied.     

Cryptococcosis in tree shrews (Tupaia tana and Tupaia minor) and elephant shrews (Macroscelides proboscides)

OBJECTIVE: To determine the relation between metabolic and anthropometric parameters and circulating leptin concentrations in women with polycystic ovary syndrome (PCOS). DESIGN AND PATIENTS: Correlation of fasting serum leptin concentrations with anthropometric measures and multiple metabolic parameters including insulin and glucose responses to a 2-hour 75-g oral glucose tolerance test (OGTT) in 85 women with PCOS (17-36 years, body mass index (BMI) 29.9 +/- 0.9 kg/m2, mean +/- SD) and 18 control women (25-47 years, BMI 25 +/- 1.7 kg/m2). Diagnostic criteria for PCOS: characteristic ovarian morphology on ultrasound plus at least two of (1) elevated serum testosterone; (2) elevated serum androstenedione; and (3) reduced serum SHBG concentrations. MEASUREMENTS: Concentrations of androgens, lipids, PRL, gonadotrophins, and leptin were measured in the baseline fasting blood sample from an OGTT. Insulin and glucose were measured throughout OGTT. Serum leptin concentrations were measured by radioimmunoassay. RESULTS: Log leptin levels in the PCOS group correlated significantly with BMI (r = 0.85, P < 0.0001) and with 8 other parameters including waist/hip ratio (r = 0.51, P = 0.0005). By stepwise regression analysis, only BMI (P < 0.0001) and plasma high density lipoprotein concentration (P = 0.02) were independently correlated with log leptin levels, both positively. There was no effect of fat distribution, as measured by waist/ hip ratio, on leptin concentrations. Comparison of control subjects to a BMI-matched subgroup of 55 PCOS subjects revealed significantly higher circulating concentrations of LH, testosterone, DHEAS, progesterone and androstenedione, and higher glucose and insulin responses to OGTT in the PCOS group. Leptin levels were not different between the PCOS subgroup and control group (14.8 +/- 1.3 vs 12.1 +/- 2.3 micrograms/l, mean +/- SE, P = 0.26) and the relation of BMI to leptin levels determined by linear regression analysis also did not differ between the two groups. CONCLUSIONS: Our results indicate that circulating leptin concentrations in women with PCOS, a condition characterized by hyperandrogenaemia, increased LH concentrations and insulin resistance, are strongly related to BMI and not independently affected by circulating levels of insulin, gonadotrophins or sex hormones.     

Common region of ALL-1 gene disrupted in epipodophyllotoxin-related secondary acute myeloid leukemia

Translocations at chromosomal band 11q23 characterize most de novo acute lymphoblastic leukemias (ALL) of infants, acute myeloid leukemias (AML) of infants and young children, and secondary AMLs following epipodophyllotoxin exposure. The chromosomal breakpoints at 11q23 have been cloned from isolated cases of de novo ALL and AML. Using an 859-base pair BamHI fragment of human ALL-1 complementary DNA that recognizes the genomic breakpoint region for de novo ALL and AML, we investigated two cases of secondary AML that followed etoposide-treated primary B-lineage ALL. In the first case, the translocation occurred between chromosomes 9 and 11 and the breakpoint at 11q23 localized to the same 9-kilobase region of the ALL-1 gene that is disrupted in most of the de novo leukemias. In the second case the translocation was between chromosomes 11 and 19. The breakpoint occurred outside of the ALL-1 breakpoint cluster region.     

Treatment of perianal fistulas with ND:YAG laser--results in twenty cases

Excision of perianal fistulas using a 1.064 micron wavelength neodymium:yttrium aluminum garnet (ND:YAG) contact tipped laser with primary wound closure was used to treat 20 dogs with perianal fistulas. Overall, 19 of 20 (95%) dogs had resolution of fistulas after one or more ND:YAG treatments. The period of resolution ranged from 10 to 42 months with a mean of 22.9 months. Sixteen of 20 (80%) dogs had resolved fistulas after one laser excision. Three of the four recurrences underwent additional laser treatments with successful results. The total number of laser procedures ranged from one to three with a mean of 1.2 procedures. Postoperatively, anal tone as judged by digital rectal examination was reduced in about 60% of the cases, but clinical evidence of fecal incontinence only occurred in four of 20 cases. This was managed effectively with diet modification. The tendency toward loss of anal tone or fecal incontinence depended on the severity of preexisting anal stenosis. On a client survey, 19 of 20 owners believed that their animals experienced less pain during defecation after surgery and rated the results as excellent or good. The overall success rate using ND:YAG laser excision compared very favorably with previously reported studies of other methods of treatment for perianal fistulas in dogs.     

Amifostine (WR-2721) shortens the engraftment period of 4-hydroperoxycyclophosphamide-purged bone marrow in breast cancer patients receiving high-dose chemotherapy with autologous bone marrow support

4-Hydroperoxycyclophosphamide (4-HC), a commonly used marrow-purging agent, is active against many tumors, but is also toxic to normal marrow progenitors. Amifostine (WR-2721) is a sulfhydryl compound with chemoprotectant activity. Preclinical studies using suspensions of bone marrow and breast cancer cells demonstrated that ex vivo treatment with amifostine followed by 4-HC resulted in protection of marrow progenitors, with no compromise in the antitumor effect of 4-HC. This fact stimulated the development of a clinical trial. Bone marrow was harvested from 15 poor-prognosis breast cancer patients and randomly assigned to ex vivo treatment with amifostine followed by 4-HC (amifostine + 4-HC), or treatment with 4-HC alone. High-dose chemotherapy was then administered followed by infusion of the purged autologous bone marrow support (ABMS). Leukocyte engraftment, defined as a white blood cell count > or = 1 x 10(9)/L, was achieved in an average of 26 days for patients whose marrow was purged with amifostine + 4-HC versus 36 days for patients whose marrow was purged with 4-HC alone (P = .032). The average number of platelet transfusions (12 v 29; P = .017) and days of antibiotic therapy (28 v 40; P = .012) were significantly less for patients whose marrow was exposed to amifostine + 4-HC, compared with 4-HC alone. Unpurged backup marrow fractions were infused into three patients whose marrow was purged with 4-HC alone, because of inadequate marrow recovery. None of the patients who received amifostine + 4-HC-purged marrow required a backup marrow fraction. Complete remissions were achieved in 83% of patients with measurable disease, with no difference between the two cohorts. Forty-three percent of patients remained alive and progression-free at a mean of 13 months posttransplant. There was no significant difference in the rate or pattern of relapse for patients whose marrow was purged with amifostine + 4-HC compared with those whose marrow was purged with 4-HC alone. Ex vivo treatment of marrow with amifostine significantly shortens the time to marrow recovery, thereby reducing the risk of myelosuppressive complications in breast cancer patients receiving high-dose chemotherapy and 4-HC-purged ABMS. Since supportive care requirements are also significantly decreased, amifostine may reduce the cost of such therapy.     

Ex vivo expansion with stem cell factor and interleukin-11 augments both short-term recovery posttransplant and the ability to serially transplant marrow

The characterization of many cytokines involved in the control of hematopoiesis has led to intense investigation into their potential use in ex vivo culture to expand progenitor numbers. We have established the optimum ex vivo culture conditions that allow substantial amplification of transient engrafting murine stem cells and which, simultaneously, augment the ability to sustain serial bone marrow transplantation (BMT). Short-term incubation of unfractionated BM cells in liquid culture with stem cell factor (SCF) and interleukin-11 (IL-11) produced a 50-fold amplification of clonogenic multipotential progenitors (CFU-A). Following such ex vivo expansion, substantially fewer cells were required to rescue lethally irradiated mice. When transplanted in cell doses above threshold for engraftment, BM cells expanded ex vivo resulted in significantly more rapid hematopoietic recovery. In a serial transplantation model, unmanipulated BM was only able to consistently sustain secondary BMT recipients, but BM expanded ex vivo has sustained quaternary BMT recipients that remain alive and well more than 140 days after 4th degree BMT. These results show augmentation of both short-term recovery posttransplant and the ability to serially transplant marrow by preincubation in culture with SCF and IL-11.