Cell-Growth Kinetics and Karyotype Analysis of Human Memory Lymphocytes Responding to Alloantigen and Mitogen

Peripheral-blood lymphocytes were primed in vitro with the mitogen phytohemagglutinin (PHA) or with allogeneic cells and their memory responses studied following sequential restimulation with either mitogen or alloantigen. Chromosome preparations were made every 12 hours following exposure to the stimulating agents. Cultures were labeled with BUdR for sister-chromatid staining of the chromosomes which provided information about the kinetics of cell growth and rates of sister chromatid exchange. Cultures containing no BUdR were used for the investigation of cell karyotypes after chromosome-banding.Following PHA as well as alloantigen restimulation, an earlier reaction of the responding cells was observed. The peak response after the first stimulation was found at 120 h with allogeneic stimulation and at 60 h with mitogen stimulation. In the second round of stimulation, the peak occurred after 48 h (allogeneic) and 36 h (PHA) and following the third stimulation after 36 h (allogeneic) and 24 h (PHA). The speed of cell growth was decreased following restimulation with either alloantigen and mitogen. In contrast to the allogeneic restimulation, the number of cells responding after PHA restimulation was decreased.No systematic numerical or structural aberration of the karyotype was detected following repeated stimulation with either alloantigen or mitogen. In this sense, the lymphocyte subpopulations selected by repeated stimulation did not differ from the starting material. On the other hand, the sister-chromatid exchange (SCE) frequency was increased following allogeneic restimulation, whereas it remained constant with PHA restimulation.     

Retrospective Study on the Efficacy and Safety of Quinacrine Sterilization

Objective To observe and evaluate the efficacy and safety of quinacrine sterilization.Methods A total of 572 cases of quinacrine sterilization preformed during the 4 years from 1993to 1997in Jiangsu and Guizhou Provinces were employed in this study. The efficacy and safety of quinacrine sterilization in those case were studied and evaluated, with 588 cases of surgical sterilization performed at the same time being the control group.Results Both groups were with identical demographic and gynecological characteristics. The result of multiple decrement life table analysis showed the 12th gross cumulative failure rates for quinacrine sterilization was 3. 13% and serious side effects occurred in only 2 cases accounting for O. 35%. One was ectopic pregnancy (20 months after treatment). The other was due to anaphylaxis in 10 minutes after the second insertion). No difference in the liver and nephic functions was detected and no suspected cancer cells or cancer cells were found in the two groups. 99. 6% of the 572 women interviewed accepted the quinacrine sterilization.Conclusions Quinacrine sterilization method is with high acceptability but comparatively low effectiveness. It has been proved to be a safe method of contraception in short-term. However, the safety of long-term still needs further study.     

A prospective study to evaluate the efficacy of modified swim-up preparation for male sex selection

A previously published study reporting the use of a modifiedswim-up technique for sperm preparation prior to inseminationwhich resulted in a high percentage of male births has beencriticized for its lack of controls. The present prospectivestudy was initiated to investigate further the efficacy of modifiedswim-up preparation for male sex-selection when applied in aproperly defined control group. Our results showed that theproportion of males born in singleton pregnancies was 50% inthe group inseminated following sperm preparation with Percolland in the control group with no sperm preparation comparedwith 88.5% in the group treated with the modified method ofswim-up sperm preparation prior to insemination. This high rateof males in the group treated with modified swim-up was alsoobserved in singleton pregnancies of women taking ovulationinducing drugs (primarily clomiphene citrate). This contrastswith previous publications in which a higher rate of femaleswas found in clomiphene citrate patients using the albumin separationtechnique. How the mechanism of the swim-up procedure may resultin a high male birth rate remains unclear. A high percentageof y enriched semen was found using fluorochrome quinacrinemustard staining but this procedure may falsely stain autosomalchromosomes. If analysis using sensitive DNA probes fails toconfirm the y enrichment of the spermatozoa, one must hypothesizethat the modified swim-up procedure damages the x-spermatozoa.     

Treatment of Giardiasis after Nonresponse to Nitroimidazole

During January 2008–October 2013, a total of 12 cases of giardiasis at the Chaim Sheba and Shaare Zedek Medical Centers, Israel, did not respond to nitroimidazole; 83.3% were associated with travel and 33% with immunoglobulin deficiency. Among 110 published cases, the most effective treatment was quinacrine (efficacy 90%–100%), but its availability is limited.     

Acute monocytic leukemia chromosome studies

Cytogenetic studies have been performed on 34 acute monocytic leukemia (M5) patients, 24 of the a type and 10 of the b type. No chromosomal abnormalities were found in 12 cases, in spite of the fact that the mitoses concerned monocytes. Different chromosomal aberrations were present in the other cases. In 12 of them, an abnormality of the chromosome 11 long arm was observed (mainly in the poorly differentiated type of M5), on bands q22–q24 in nine cases and on band q14 in three cases. The chromosome 11 long arm thus appears preferentially rearranged in M5 although this is not apparent in every case. Concomitant study of the mitoses with cytological and cytogenetic techniques suggests that erythroblasts may not be involved in the M5 leukemic process.     

Non-glycosylphosphatidylinositol (GPI)-anchored recombinant prion protein with dominant-negative mutation inhibits PrPSc replication in vitro

Dominant-negative mouse prion protein (PrP) with a lysine mutation at codon 218 (Q218K) is known to inhibit prion replication. In order to gain further mechanistic insight into such dominant negative inhibition, non-glycosylphosphatidylinositol (GPI)-anchored recombinant PrP with Q218K (rPrP-Q218K) was investigated. When applied into scrapie-infected mouse neuroblastoma (ScN2a) cells, rPrP-Q218K but not wild-type rPrP (rPrP-WT) exclusively inhibited abnormal protease-resistant pathogenic isoform (PrP^Sc) replication without reducing the viability of the cells. It was even more efficient than quinacrine, which has already been prescribed for sporadic Creutzfeldt-Jakob disease (CJD) patients; 50% effective concentration (EC₅₀)?=?0.20?μM, 99% effective concentration (EC₉₉)?=?0.86?μM vs. EC₅₀?=?0.45?μM, EC₉₉?=?1.5?μM. Besides, no apparent cell damage was observed at the concentration of up to 4.3?μM (100?μg/ml). In combination treatment with 0.43?μM (10?μg/ml) of rPrP-Q218K, EC₉₉ of quinacrine was decreased from 1.5?μM to 0.5?μM, and the cell viability was recovered from 50% to over 90% as inversely proportional to the concentration of quinacrine. Such combination could alleviate the side effects of quinacrine by reducing its effective concentration without changing or even acceleration the inhibition efficacy. Since homogeneous, high-quality rPrPs could be easily prepared from Escherichia coli in large quantities, rPrP-Q218K is a good candidate for a prion replication antagonist.     

Postcardioplegic Myocardial Recovery: Effects of Halothane, Nifedipine, HOE 694, and Quinacrine

Halothane has been shown to be a powerful myocardial protectant during normothermic cardioplegic arrest and subsequent reperfusion. In view of its multiple effects on cellular Ca²⁺ movements and the role of this ion in ischemia-reperfusion injury, the questions of whether halothane is capable of maximally protecting the heart or whether combination therapy of halothane with other Ca²⁺ blocking agents may be more effective arose. Therefore, the effects of combination therapy with halothane and a calcium antagonist (nifedipine), or a Na⁺/H⁺ inhibitor (HOE 694), or a Na⁺/Ca²⁺ inhibitor (quinacrine) on postcardioplegic functional recovery were evaluated. The isolated perfused rat heart subjected to 45 minutes normothermic cardiac arrest was used as an experimental model. Dose–response curves were performed for each drug. Using the optimal dosage for each drug, the following results were obtained: (1) Nifedipine (10^–7 M; administered retrogradely 10 minutes before and after cardioplegia) and halothane (1.5% administered during cardioplegia), when administered separately, improved functional recovery. Combination therapy did not further improve protection. (2) HOE 694 (10^–7 M) or quinacrine (10^–9 M) improved postcardioplegic functional recovery when added for 2 minutes at the onset of reperfusion. Simultaneous administration of HOE 694 and 1.5% halothane was the only combination that yielded additive protection. (3) Quinacrine, a phospholipase and Na⁺/Ca²⁺ exchanger inhibitor, appeared to be the most powerful drug used. In summary, the results obained indicate that interventions aimed at preventing intracellular Ca²⁺ overload improve recovery after cardioplegic arrest. The beneficial effects of halothane could be further improved by HOE 694.