Defects of natural killer cell activity in children with untreated acute lymphocytic leukemia

Summary Natural killer (NK) activity against cells of the K-562 line was significantly depressed in 12 of 18 children (66%) with untreated acute lymphocytic leukemia (ALL). No suppression of allogeneic NK activity was observed with sera of the patients, regardless of the level of NK depression. The ability of peripheral blood lymphocytes (PBLs) to suppress allogeneic NK activity was tested in two ALL patients — one with no detectable NK activity, and one with high NK activity. No NK-suppressive activity was found with PBLs of the areactive patient; PBLs of the reactive patients exhibited some suppressive activity, but only at a particular suppressor-to-effector cell ratio. Leukemic blasts were resistant to killing by autologous NK cells stimulated by IFN, as well as to killing by allogeneic, IFN-stimulated PBLs. Leukemic blasts of an ALL patient inhibited lysis of K-562 cells in an 18-h, but not in a 4-h NK assay. The inhibition could partly be reversed by pretreatment of ALL cells with alpha interferon, suggesting that the blasts might inhibit the lysis of K-562 targets in a competitive manner. Disturbed function and/or regulation of NK cells may influence attempts at NK cell activation by lymphokines.Abbreviations ALL acute lymphocytic leukemia - AML acute myeloid leukemia - CLL chronic lymphocytic leukemia - CML chronic myeloid leukemia - IFN interferon - IL-2 interleukin-2 - LGL large granular lymphocyte - NK cell natural killer cell - PBL peripheral blood lymphocyte - Poly I:C polyinosinic-polycytidylic acid     

Screening for cognitive impairment in older adults attending an eye clinic

PURPOSE: We conducted a cross-sectional study examining potentially modifiable factors associated with cognitive impairments (mild or severe) in older whites, African Americans and Hispanics attending an outpatient eye clinic. METHODS: In-clinic interviews and physical examinations assessed social, demographic and health information from 100 consecutive Hispanic, African-American and white adults aged > or = 55. Our primary outcome was presence of any cognitive impairment (mild or severe) using the St. Louis University Mental Status Examination (SLUMS) scale. RESULTS: Of the 100 subjects, 65 screened positive for cognitive impairments on the SLUMS cognitive instrument: 46 with mild cognitive impairment and 19 with severe impairment (possible dementia). African-American and Hispanic adults (nonwhites) were significantly more likely to have cognitive impairment compared to white adults (OR 2.80: 95% CI = 1.05-7.44), independent of age, years of education and systolic blood pressure. Subjects with diabetes also had increased odds of cognitive impairments (OR 3.28, 95% CI = 1.21-8.90) even after adjusting for relevant confounders. There was a nonsignificant trend between visual acuity impairment and cognitive impairment (p = 0.059). CONCLUSIONS: Sixty-five percent of adults aged > or = 55 attending the eye clinic screened positive for cognitive impairments, with higher rates among nonwhites and adults living with diabetes.     

Multiple karyotypic aberrations in a polymorphous variant of Waldenstr?m macroglobulinemia.

A 71-year-old woman presented with malaise, skin bruising, epistaxis, and gingival bleeding of recent and prompt onset. There was no adenopathy. The liver and spleen were not enlarged. Bone marrow aspirate showed a polymorphous infiltration with lymphocytes (22%), typical Marschalko plasma cells (16%), plasmacytoid lymphocytes (29%), lymphoblasts (8%), and immunoblasts (13%). The immunoblasts morphologically resembled lymphosarcoma cells with a frequent "clover-leaf" appearance. An IgM paraprotein concentration in serum was 38.5 g/L. The bone marrow histopathology confirmed the presence of heterogenous cell infiltration, with 30% of the population being comprised of lymphoblasts and immunoblasts. In order to differentiate a polymorphous variant of Waldenstr?m macroglobulinemia (WM) from the more common small cell lymphocytic lymphoma (SLL) in anaplastic metamorphosis, flow cytometric studies were performed on marrow specimens. A typically bright surface IgM (lambda) was demonstrated with a less bright CD38. Further immunophenotype was HLA-DR+, CD19+, CD20+ and CD10-, CD22-, T-Ag- and kappa light chain- expression. This corroborated the diagnosis of an extremely rare, polymorphous variant of WM. The marrow cytogenetics disclosed 50% (10/20) pathologic metaphases 48,X,dup(X)(p21p22),der(2), +5,del(6)(q11q21), +12,inv(16)(p13q22), del(17) (p12), and 50% normal metaphases. The patient was treated with a LOPP protocol. She failed to respond and died 5 months after the diagnosis with myocardial and renal insufficiency complicating a pronounced pancytopenia in the peripheral blood.     

Approval summary: Docetaxel in combination with prednisone for the treatment of androgen-independent hormone-refractory prostate cancer.

PURPOSE: Docetaxel, a taxane previously approved for the treatment of breast cancer and non-small cell lung cancer, was approved by the United States Food and Drug Administration on May 19, 2004 for use in combination with prednisone for the treatment of metastatic androgen-independent (hormone-refractory) prostate cancer. The purpose of this summary is to review the database supporting this approval. EXPERIMENTAL DESIGN: In a randomized, global study enrolling 1,006 patients, two schedules of docetaxel were compared with mitoxantrone + prednisone as follows: MTZ q 3w, mitoxantrone 12 mg/m2 every 21 days + prednisone 5 mg twice a day for a total of 10 cycles; TXT q 3w, docetaxel 75 mg/m2 every 21 days + prednisone 5 mg twice a day for a total of 10 cycles; and TXT qw, docetaxel 30 mg/m2 days 1, 8, 15, 22, and 29 every 6 weeks + prednisone 5 mg twice a day for a total of 5 cycles. RESULTS: There was a statistically significant overall survival advantage shown for the TXT q 3w arm over MTZ q 3w (median survival 18.9 months versus 16.5 months, P = 0.0094). No overall survival advantage was shown for TXT qw compared with MTZ q 3w. The most commonly occurring adverse events included anemia, neutropenia, infection, nausea, sensory neuropathy, fluid retention, alopecia, nail changes, diarrhea, and fatigue. CONCLUSIONS: This report describes the Food and Drug Administration review supporting this first approval of a combination therapy for hormone-refractory prostate cancer based on demonstration of a survival benefit.     

Loss of base excision repair in aging rat neurons and its restoration by DNA polymerase beta

Synthetic staggered oligodeoxynucleotide duplexes are formed by annealing a 5'-32P-labeled 14-mer with four different 21-mers. These duplexes have either a correct or mismatched base pair at 3'-end of the primer. With these model template primers the ability of neuronal extracts, obtained from rats of different ages, to extend the primer to the predicted length was tested. While the neuronal extracts of all ages were able to degrade the 14-mer to shorter lengths, extension of the primers in general and in particular, the mismatched, is achieved only feebly by the young and adult neuronal extracts and undetectable with old neuronal extracts. The possibility of restoring the lost activity by supplementing the neuronal extracts with pure DNA polymerases was examined. Of the three polymerases tested (calf thymus alpha polymerase, E. coli DNA polymerase I and rat liver DNA polymerase beta) only polymerase beta gave consistent and encouraging results although the extension was slow and distributive in nature and mismatched primers were extended much less efficiently than the correctly paired primer. However, significantly improved extension, including those of mismatched primers, was achieved by prior removal of mismatched bases in a preincubation with just the neuronal extracts (3'-5'exonuclease activity) followed by extension by the added polymerase beta and dNTPs in the presence of Mn(2+) instead of the usual Mg(2+). These results are taken to indicate that the activity of polymerase beta in brain cells is compromised with age and that this deficit can be corrected in vitro by the addition of pure recombinant rat liver polymerase beta under appropriate conditions.     

Impact of the malaria parasite on reproductive indices of male mice

Aim:  To investigate the impact and possible mechanism of action of the rodent malarial parasite on reproduction.
Methods:  Male albino mice were infected with 15, 30 and 45% Plasmodium berghei berghei through inoculation with 10⁷ parasitized red blood cells. Each experiment had its own control that was not infected with P. berghei berghei . Mice infected with 15% P. berghei berghei were killed on days 0, 5, 10 and 15; those infected with 30% P. berghei berghei were killed on days 0, 3, 6 and 10; and those infected with 45% P. berghei berghei were killed on days 1–7 after infection. Caudal epididymal sperm motility, counts and morphology, body and wet organ weights and hematological indices were determined.
Results:  The results showed a progressive duration dependent decrease in sperm motility, sperm count and viability ( P  < 0.01) in parasitized mice. There were significant decreases in serum testosterone and increases in cortisol levels ( P  < 0.05) in the infected mice compared with the controls. There was also a progressive decrease ( P  < 0.05) in red blood cell count and packed cell volume. However, there was a progressive increase ( P  < 0.01) in white blood cell count and weight of the spleen and liver. There was no significant change in weight of the testis and epididymides.
Conclusion:  The results suggest that the malaria parasite could depress male fertility indices. (Reprod Med Biol 2006; 5 : 201–209)     

Leptospirosis among zebu cattle in farms in Kaduna State,Nigeria

ObjectiveTo assess the occurrence of Leptospira spp serovar Hardjo among Zebu cattle in some livestock producing areas of Kaduna State, Nigeria.MethodsSera samples were obtained from 164 Zebu breed of cattle above one year osf age in seven cattle farms were screened for antibodies to Leptospira spp. serovar Hardjo using Enzyme linked immunosorbent assay (ELISA).ResultsAntibodies to Leptospira spp. serovar Hardjo were detected in eighteen (10.98%) out of the 164 animals sampled. There was no significant difference (P>0.05) in seropositivity between the different age groups or between different Zebu breeds.ConclusionThe presence of Leptospirosis among the Zebu breeds of cattle may poses a threat to livestock production and has public health implication due to its zoonotic potential.