Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation

Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by gradient centrifugation for use in assisted reproductive procedures. Efficacy was assessed in terms of percentages of sperm recovery, sperm vitality and motility, normal sperm morphology and normal sperm chromatin condensation. No significant difference was found in the recovery of spermatozoa for men with both normal sperm counts and oligozoospermia, between PVP-coated and silane-coated particle solutions. Iodixanol had significantly lower sperm recovery compared to the other products. Sperm vitality, progressive motility, normal morphology and normal chromatin condensation did not differ significantly between any of the sperm isolation products.      

Protective cytotoxic T lymphocyte responses against paramyxoviruses induced by epitope-based DNA vaccines: involvement of IFN-gamma

Plasmid DNA vectors have been constructed with minigenes encoding a single cytotoxic T lymphocyte (CTL) epitope from either the M2 protein of respiratory syncytial virus (RSV) or from the nucleoprotein of measles virus (MV) with or without a signal sequence (also called secretory or leader sequence). Following intradermal immunization, plasmids in which the CTL epitopes were expressed in-frame with the signal sequence were more effective at inducing peptide- and virus- specific CTL responses than plasmids expressing CTL epitopes without the signal sequence. This immunization resulted in protection against MV-induced encephalitis and a significant reduction in viral load following RSV challenge. The reduction of viral load following RSV challenge was abrogated by prior injection with anti-IFN-gamma antibodies. These results highlight the ability of epitope-based DNA immunization to induce protective immune responses to well-defined epitopes and indicate the potential of this approach for the development of vaccines against infectious diseases.      

Addressing psychological aspects of physical problems through sandplay: A grounded theory study of therapists’ views

Objectives. This study aimed to explore therapists’ understanding of how people with a wide range of physical problems address the psychological aspects of these problems through sandplay, what happens for them in the process, what changes they experience and what sandplay can contribute to working with such people. Design. This exploratory qualitative study used grounded theory to systematically analyse the data and construct a substantive theory of therapists’ understanding of the processes and themes involved in sandplay therapy with people with physical problems. Methods. Semi‐structured interviews were carried out with nine sandplay therapists with the participants asked about their experiences of using sandplay to address physical problems. Results. The participants offered evidence of their clients’ ability to address their physical problems and the corresponding psychological issues through symbolic expression in the sand. The emergent theory suggested that such symbolic expression could facilitate access to feelings and experiences that can be difficult to address through verbal therapy alone, thus facilitating the process of integration and recovery. Conclusions. The theory suggests how therapists thought that clients may address their physical problems through sandplay and what is important in that process. There was also a suggestion that the focus and themes unfolding in sandplay process may vary depending on whether the clients present with somatisation, chronic illness, or terminal illness.     

Anicteric hepatoxicity: a potential health risk of occupational exposures in Nigerian petroleum oil refining and distribution industry

Background

Literature abounds linking one’s job to certain unpalatable health outcomes. Since exposures to hazardous conditions in industrial environments often results in sundry health effects among workers, we embarked on this study to investigate the hepatic health effects of occupational activities in the petroleum refining and distribution industry.

Method

Biochemical markers of liver functions were assayed in plasma, using Reflotron dry chemistry spectrophotometric system. The study was conducted on randomly selected workers of Port Harcourt Refining Company (PHRC) and Pipelines and Petroleum Product Marketing Company (PPMC) both in Alesa-Eleme near Port Harcourt, Nigeria, as well as non-oil work civil servants serving as control subjects.

Result and conclusion

Results showed that, bilirubin ranged 0.3-1.6 mg/dl with a mean of 0.66±0.20mg/dl among the oil workers as against 0.5-1.00mg/dl with a mean of 0.58±0.13mg/dl in non-oil workers, Alkaline phosphatase ranged 50.00-296.00u/l (mean: 126.21±39.49u/l) in oil workers as against 40.20-111u/l (mean: 66.83±18.54u/l) for non-oil workers, Aspartic transaminases (AST) ranged 5.80-140.20u/l (mean: 21.81±11.49u/l) in oil workers against 18.00-44.00u/l (mean: 26.89±6.99u/l) for non-oil workers, while Alanine transaminases (ALT) ranged 4.90-86.00u/l (mean: 22.14±11.28u/l) in oil workers as against 10.00-86.60u/l (mean: 22.30±10.22u/l) for the non-oil workers. A close study of the results revealed that although the mean values for all the studied parameters were still within the parametric reference ranges, however, relative to the referents, there were significant increases (P<0.05) in plasma bilirubin (though anicteric) and alkaline phosphatase that was not matched with a corresponding increase in the plasma transaminases, suggesting a possibility that toxic anicteric hepatoxicity is part of the potential health effects of sundry exposures in the Nigeria petroleum oil refining and distribution industry. Gender differentiation data showed that though the mean values for the parameters were higher in males than females, the increases were not significant in most cases (P>0.05), whereas data for age and exposure period classifications revealed that irrespective of the age of the worker, the effects are likely to start after the first five years, manifesting fully after the first decade of occupational exposures. Thus, an update of industrial/occupational health measures is necessary for a safer and healthier work environment.     

Analysis of the relationship between age and treatment response in migraine

In migraine, headache severity varies with age. As a consequence, the effectiveness of medication may also depend on a patient's age. The purpose of this study was to assess the combined effect of age and drug treatment on headache characteristics. Using data from clinical trials of sumatriptan in adolescents and adults, we show how the interaction between age and drug exposure can be parameterised as a covariate on a Markov model that describes the decline of headache severity over three clinically defined stages (no relief, relief and pain-free status). The model explains important clinical observations: (i) the rates at which the pain relief and pain-free status were attained were found to be inversely related to age; (ii) in placebo-treated patients, the mean transit time from 'no relief' to 'relief' is 3 h for young adolescents and increases to 6 h for patients aged ≥ 30 years; and (iii) sumatriptan reduces the transit time to 2 h, irrespective of age. These findings indicate that the therapeutic gain over placebo increases with age. Prospective studies of antimigraine drugs should take this relationship into account when extrapolating efficacy data from adults to adolescents.     

Effect of donor cell age on the efficiency of nuclear transfer in rabbits

The ability of rabbit fibroblasts of different ages to be reprogrammed following nuclear transfer (NT) to aged recipient oocytes was evaluated. The rate of NT blastocysts reconstructed with presumptive G1 stage morula cells or fetal fibroblasts was significantly higher (41.5% and 51.4%) than was those of cloned embryos reconstructed with fibroblasts from young (4-month-old) or aged (5-year-old) animals (16.7% and 7.1%, respectively, P < 0.025). Serum starvation significantly increased the development of NT embryos to the morula-blastocyst stage (67.6% versus 22.9%, P < 0.025). Transfer of 168 NT embryos derived from nuclei of morula cells and 106 control embryos into 21 recipients resulted in 10 pregnancies, 2 NT and 18 control pups, respectively. In the first experiment, transfer of 142 cleaved NT embryos reconstructed with fetal fibroblasts and 86 control embryos into eight recipient does resulted in five pregnancies and the birth of 20 control pups. In the second experiment, after transfer of 112 NT embryos derived from fetal fibroblasts into six recipients, 10 (8.9%) sites of implantation were revealed in two does (33.3%) on day 14 of gestation. This study provides evidence that nuclei of morula cells and fetal and adult fibroblasts differ in their ability to be reprogrammed by recipient cytoplasm following nuclear transfer.