Protein and enzyme electrophoresis profiles of selected Candida species.

The cellular protein profiles and malate dehydrogenases, superoxide dismutases, alkaline phosphatases, and esterases from whole cell extracts of Candida spp. were studied with polyacrylamide gel electrophoresis. We investigated isolates that differed in their ability to assimilate sucrose as the sole carbon source. The protein and enzyme patterns of Candida tropicalis and its sucrose-negative variant "Candida paratropicalis Baker, Salkin, Pincus et D'Amato" were indistinguishable. Although the cellular protein and superoxide dismutase patterns of Candida albicans and its sucrose-negative variant "Candida stellatoidea" were quite similar, differences were noted in the profiles of the other enzymes studied. In addition, the C. stellatoidea isolates were found to be separable, on the basis of their enzyme profiles, into the same two types that have been reported by Kwon-Chung et al. (K.J. Kwon-Chung, B.L. Wickes, and W.G. Merz, Infect. Immun. 56:1814-1819, 1988).     

Haemoglobin K Woolwich: a study of the family of a homozygote.

A family is described in which the proband is homozygous and several relatives are heterozygous for Hb K Woolwich (beta 130 [H10] Lys leads to Gln). These people are clinically and haematologically normal. The relationship between the presence of Hb K Woolwich and beta +-thalassaemia is discussed. The distribution of Hb K Woolwich in West Africa is discussed and it is seen to be closely associated with the Akan group.     

Detection of gene amplification in archival breast cancer specimens by laser-assisted microdissection and quantitative real-time polymerase chain reaction

Gene amplification is one of the most important mechanisms leading to deregulated gene expression in cancer. The exact quantitative detection of this frequent genomic alteration in solid tumors is often hampered by an admixture of nonneoplastic bystander and stroma cells. To overcome this obstacle and to develop an objective quantitative method we have combined laser-assisted microdissection of tumor cells with the novel 5'-exonuclease-based real-time polymerase chain reaction (PCR) assay. The latter method enables the highly reproducible exact quantification of minute amounts of nucleic acids. As a model system amplification of c-erbB2/Her-2/neu gene and the adjacent topoisomerase IIalpha gene was determined in paraffin-embedded breast cancer specimens (n = 23) after immunohistochemical labeling and laser-based microdissection of tumor cells. The high sensitivity of real-time PCR enabled the reliable and objective detection of low-level amplifications in as few as 50 cells from archival tissue sections. Low-level amplifications were shown to escape from detection unless tumor cells were isolated by microdissection. In selected cases intratumor heterogeneity was demonstrated using areas of approximately 50 to 100 cells. This novel approach combining immunohistochemistry, laser microdissection, and quantitative kinetic PCR allows morphology-guided studies in archival tissue specimens and will enable the exact quantification of gene copy numbers in even small and precancerous lesions.     

Nursing constraint models for electronic health records: a vision for domain knowledge governance

Various forms of electronic health records (EHRs) are currently being introduced in several countries. Nurses are primary stakeholders and need to ensure that their information and knowledge needs are being met by such systems information sharing between health care providers to enable them to improve the quality and efficiency of health care service delivery for all subjects of care. The latest international EHR standards have adopted the openEHR approach of two-level modelling. The first level is a stable information model determining structure, while the second level consists of constraint models or 'archetypes' that reflect the specifications or clinician rules for how clinical information needs to be represented to enable unambiguous data sharing. The current state of play in terms of international health informatics standards development activities is providing the nursing profession with a unique opportunity and challenge. Much work has been undertaken internationally in the area of nursing terminologies and evidence-based practice. This paper argues that to make the most of these emerging technologies and EHRs we must now concentrate on developing a process to identify, document, implement, manage and govern our nursing domain knowledge as well as contribute to the development of relevant international standards. It is argued that one comprehensive nursing terminology, such as the ICNP or SNOMED CT is simply too complex and too difficult to maintain. As the openEHR archetype approach does not rely heavily on big standardised terminologies, it offers more flexibility during standardisation of clinical concepts and it ensures open, future-proof electronic health records. We conclude that it is highly desirable for the nursing profession to adopt this openEHR approach as a means of documenting and governing the nursing profession's domain knowledge. It is essential for the nursing profession to develop its domain knowledge constraint models (archetypes) collaboratively in an international context.     

Prostaglandin D synthase (beta-trace) in healthy human sleep

STUDY OBJECTIVES: The prostaglandin D system plays an important role in animal sleep. In humans, alterations in the prostaglandin D system have been found in diseases exhibiting sleep disturbances as a prominent symptom, such as trypanosoma infection, systemic mastocytosis, bacterial meningitis, major depression, or obstructive sleep apnea. Assessment of this system's activity in relation to human physiologic sleep was the target of the present study. DESIGN: Serum concentrations of lipocalin-type prostaglandin D synthase (L-PGDS, former beta-trace), and plasma levels of the pineal hormone melatonin were measured in 20 healthy humans (10 women, 10 men; aged: 23.3 +/- 2.39 years) at 4-hour intervals over a period of 5 days and nights, which included physiologic sleep, rapid eye movement sleep deprivation, and total sleep deprivation. In addition, the serum L-PGDS and plasma melatonin levels of 6 subjects were determined under conditions of bright white (10,000 lux) or dark red light (< 50 lux) in a crossover design during total sleep deprivation. Nocturnal blood sampling was performed by a through-the-wall tube system. L-PGDS was measured by an automated immunonephelometric assay, and melatonin was analyzed by direct radioimmunoassay. RESULTS: Serum L-PGDS concentrations showed marked time-dependent changes with evening increases and the highest values at night (P < .0005). This nocturnal increase was suppressed during total sleep deprivation (P < .05), independent of external light conditions and melatonin secretion. Rapid eye movement sleep deprivation had no impact on circulating L-PGDS levels. CONCLUSIONS: The circadian L-PGDS pattern and its suppression by total sleep deprivation indicate an interaction of the prostaglandin D system and human sleep regulation. L-PGDS measurements may well provide new insights into physiologic and pathologic sleep regulation in humans.     

Engulfment of mast cell secretory granules on skin inflammation boosts dendritic cell migration and priming efficiency

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Strain delineation and epidemiology of Candida (Clavispora) lusitaniae.

Electrophoretic karyotype (EK) patterns, determined by using contour-clamped homogeneous pulsed-field electrophoresis, and isoenzyme (IZ) profiles were evaluated as methods for strain delineation among 35 isolates of Candida lusitaniae recovered from 15 patients. All isolates were identified to the species level by using conventional morphologic and physiologic criteria, and the identification was confirmed by gas-liquid chromatography analysis of the cellular fatty acids. The isolates were then typed without knowledge of the patient source. The IZ profiles showed all isolates to be closely related. Fifteen EK patterns were found; each pattern was restricted to isolates recovered from a single patient. In contrast, on the basis of heterogeneity in phosphatases, beta-glucosidases, esterases, and catalases, 10 IZ profiles were found; 4 were shared by isolates recovered from more than one patient. Multiple isolates from six patients were analyzed, and for each patient, a single EK- and IZ-defined type was found. The types of isolates obtained from two patients, after the emergence of resistance to amphotericin B, remained the same as the types of isolates obtained earlier. The data suggest that a patient becomes colonized by a single strain of C. lusitaniae which may disseminate to multiple sites, that the colonizing strain can persist during the patient's hospitalization, and that it may develop resistance to amphotericin B. Both EK patterns and IZ profiles can be used to delineate strains of C. lusitaniae, but the EK pattern provides more discriminatory power.     

Systemic and mucosal antibody responses specific to SARS-CoV-2 during mild versus severe COVID-19

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