Sex differences in olfactory identification and Wisconsin Card Sorting performance in schizophrenia: relationship to attention and verbal ability

We investigated the hypothesis that different prefrontal brain systems (i.e., dorsal vs. ventral) and sex contribute differentially to cognitive deficit in schizophrenia. Performance was assessed among clinically stable, chronic schizophrenic outpatients and matched normal control subjects on olfactory identification [on the University of Pennsylvania Smell Identification Test (UPSIT)] and on executive functions [using the Wisconsin Card Sorting Test (WCST)]. Patients were impaired on both tests compared to controls, and male schizophrenics were impaired on the WCST compared to female schizophrenics. The pattern of results suggests that gender differences on the UPSIT are mildly accentuated in schizophrenia. The data support our previous study indicating that UPSIT performance is largely independent of the executive or attentional deficits typically associated with schizophrenia, with the exception of verbal ability. Further research with larger samples is required to test the hypothesis that there is a severely impaired subgroup of male patients with diffuse prefrontal dysfunctions.     

Undergraduate nursing students' perceptions of their clinical learning environment

The clinical learning environment (CLE) is an interactive network of forces influencing student learning outcomes in the clinical setting. This study used mixed methods to identify factors characterizing students' perceptions of the CLE. The sample consisted of 229 undergraduate students in the second or third year of their biophysical nursing strand. The five subscales of the Clinical Learning Environment Scale, 'staff-student relationships', 'nurse manager commitment', 'patient relationships', 'student satisfaction' and 'hierarchy and ritual', were supported by qualitative data obtained from student interviews. Interpersonal relationships between the participants in the CLE were crucial to the development of a positive learning environment. Student satisfaction with the CLE was both a result of, and influential in creating, a positive learning environment. Nurse educators, clinical venues, and all others participating in the undergraduate nursing students' clinical education, must collaborate in order to create a CLE which promotes the development of well-educated registered nurses capable of providing safe, cost-effective patient care.     

Specific strategies in the treatment of young and middle-age patients with spontaneous intracerebral hemorrhage

The paper is based on the analysis of 235 young and middle-age patients with non-traumatic cerebral hemorrhage. Tactics of treatment is determined for each group depending on bleeding localization in accordance with World Health Organization's classification (1981). Operative treatment is recommended for lateral site of hematomas of 25 cm3 and more signs of media structures dislocation of 5 mm and more. With the development of hypertension-hydrocephal syndrome surgical intervention is directed at its elimination and where possible at hematoma's ablation. The amount of operative interventions is limited in case of medial and mixed variants of hemorrhages especially when bleedings affect mesencephal structures. In conditions of a neurosurgical clinic a pharmacotherapy is used as an independent one, as a preparation for surgical treatment as well as during operation and in postoperative period.     

Ultrapurification of <Superscript>76</Superscript>Ge-enriched GeH<Subscript>4</Subscript> by distillation

⁷⁶Ge-enriched germane has been ultrapurified by low-temperature distillation. The nature and concentration of molecular impurities in the germane samples were determined by gas chromatography/mass spectrometry, high-resolution Fourier transform IR spectroscopy, and gas chromatography. The distillate contains no more than 10⁻⁵ mol % hydrocarbons, 10⁻⁴ mol % carbon dioxide, 10⁻³ to 10⁻¹ mol % digermane and trigermane, and <3 × 10⁻⁵ mol % other impurities. A distinctive feature of the impurity composition of the isotopically enriched germane samples is the presence of silicon tetrafluoride and sulfur hexafluoride impurities.     

Systemic interleukin 2 therapy for human prostate tumors in a nude mouse model

Once the regional lymph nodes become involved in prostate carcinoma, 85% of patients develop distant metastases within 5 years, and metastatic disease is difficult to treat. We have investigated the effect of systemic interleukin 2 (IL-2) treatment on metastatic prostate carcinoma using a xenograft tumor model. Cells from a PC-3/IF cell line, produced by intrafemoral injection of human PC-3 prostate carcinoma cells, were injected in the prostate of Balb/c nude mice. Prostate tumors and para-aortic lymph nodes were resected, and tumor cells were recultured and passaged in the prostate in vivo to produce new cell lines. On day 6 following prostatic injection of these cell lines, mice were treated with i.p. injections of IL-2 at 25,000-50,000 units/ day for 5 consecutive days. The effect of IL-2 on tumor progression was assessed, and histological studies were performed on prostate tumor and lymph node sections. The tumor cell lines generated by serial prostate injection were tumorigenic and metastasized to regional para-aortic lymph nodes. Tumors of 0.4 cm were obtained by day 16 and grew to 1-1.5 cm by day 40 with metastasis to para-aortic lymph nodes. Following two to three weekly courses of 5 days of 25,000-40,000 units/day of IL-2, the growth of prostate tumors was inhibited by 94%. Higher doses of 50,000 units/ day were toxic. Histologically, prostate sections showed vascular damage manifested by multifocal hemorrhages and an influx of lymphocytes and polymorphonuclear cells into disintegrating tumors and areas of necrosis containing numerous apoptotic cells. In contrast to control mice, para-aortic lymph nodes were not enlarged in responding mice. These findings suggest that systemic IL-2 therapy can induce an antitumor response in prostate tumors and control their growth and metastasis.     

Learning to predict human error: issues of acceptability, reliability and validity

Human Error Identification (HEI) techniques have been used to predict human error in high risk environments for the past two decades. Despite the lack of supportive evidence for their efficacy, their popularity remains unabated. The application of these approaches is ever-increasing, to include product assessment. The authors feel that it is necessary to prove that the predictions are both reliable and valid before the approaches can be recommended with any confidence. This paper provides evidence to suggest that human error identification techniques in general, and SHERPA in particular, may be acquired with relative ease and can provide reasonable error predictions.     

Kindling-like state occurring on periodic increases in the extracellular K+ concentration in field CA1 in rat hippocampal slices

Transient periodic increases in the extracellular K+ concentration (20 mM, 30 sec, 3-6 episodes) led to the appearance of a kindling-like state in local neuronal networks of field CA1 of rat hippocampal slices. A criterion for the appearance of this state was a reduction in the threshold for the generation of multiple population discharges and an increase in the total number of population spikes within discharges (epileptiform activity). This state correlated with potentiation of excitatory postsynaptic potentials (EPSP) (long-term increases in pyramidal neuron excitability), but not with potentiation of glutamatergic synaptic transmission in field CA1 of hippocampal slices. The role of the various Ca2+ channels in inducing and maintaining the kindling-like state in rat hippocampal sections, evoked by periodic increases in the extracellular K+ concentration, is discussed.