Calcific uraemic arteriolopathy: a rare disease with a potentially high impact on chronic kidney disease–mineral and bone disorder

Calciphylaxis [calcific uraemic arteriolopathy (CUA)] is a rare disease at the interface of nephrology, dermatology and cardiology. CUA most often occurs in adult dialysis patients. It is only rarely seen in patients without relevant chronic kidney disease, and only anecdotal reports about childhood calciphylaxis have been published. Clinically, CUA is characterized by a typical cascade, starting with severe pain in initially often inconspicuous skin areas, followed by progressive cutaneous lesions that may develop into deep tissue ulcerations. The typical picture is a mixture of large retiform ulceration with thick eschar surrounded by violaceous, indurated, tender plaques. The histopathological picture reveals arteriolar, often circumferential, calcification and extensive matrix remodelling of the subcutis. These findings explain the macroscopic correlation between skin induration and ulceration. The prognosis in CUA patients is limited due to underlying comorbidities such as uraemic cardiovascular disease and infectious complications. The etiology of CUA is multifactorial, and imbalances between pro- and anti-calcification factors, especially in the setting of end-stage renal disease play an outstanding role. Oral anticoagulant treatment with vitamin K antagonists is a predominant CUA trigger factor. It is speculative as to why children and adolescents only develop calciphylaxis in exceptional cases, although a seldom usage of vitamin K antagonists and the preserved mineral buffering capacity of the growing skeleton may be protective.     

Preliminary characterization of ribosomes of Entamoeba invadens

The ribosomes of Entamoeba invadens trophozoites have sedimentation coefficients of 77, 53 and 36 S. Most of the ribosomal proteins are basic and their one- and two-dimensional electrophoretic patterns differ from the corresponding patterns of Escherichia coli and Saccharomyces cerevisiae. Two dozen bands were observed in the 10 000 to 100 000 molecular weight range following sodium dodecylsulfate-gel electrophoresis of amoebal ribosomal proteins. Long, thin pronase-sensitive structures were seen in electron micrographs of E. invadens ribosomal preparations.     

A Study of the Growth Patterns of Breast Carcinoma Using 3D Reconstruction: A Pilot Study

Lumpectomy with microscopically clear margins is a safe and effective approach for surgical management of breast carcinoma. Margins are positive for tumor in 18–50% of lumpectomies, as it is not possible to accurately determine the shape or microscopic borders of a tumor preoperatively or intraoperatively. We examined the 3D microanatomy and growth patterns of common breast carcinoma subtypes to provide guidance for lumpectomy surgery. Prospective consent was obtained for the use of excess tissue from patients undergoing lumpectomy or mastectomy for breast carcinoma. Tissue blocks from nine breast carcinomas were serially sectioned. Hematoxylin and eosin‐stained slides at 100 μm intervals were scanned using a Nanozoomer (Hamamatsu, Japan) microscopic‐resolution scanner. Three‐dimensional reconstructions of tumors were created from scanned images using Reconstruct, open‐access software. Breast carcinoma subtypes demonstrated characteristic growth patterns within breast tissue, which may have implications for lumpectomy surgery. Invasive ductal carcinomas showed a spherical shape, with a spiculated surface representing tumor cells infiltrating into surrounding parenchyma. Ductal carcinoma in situ appeared to spread along the duct system, creating dilated, tortuous, tumor‐filled ducts. The invasive lobular carcinomas examined had a haphazard, linear, infiltrative growth pattern, different from the shape seen in ductal carcinomas. Our preliminary work suggests that invasive ductal and invasive lobular carcinomas appear to have distinct growth patterns in three dimensions and ductal carcinoma in situ appears to grow in a linear fashion along the duct network. The microanatomy studies described have the potential to guide refinements in breast lumpectomy technique.     

Molecular characterization of a mannoprotein with homology to chitin deacetylases that stimulates T cell responses to Cryptococcus neoformans

The fungus Cryptococcus neoformans is a major cause of morbidity and mortality in patients with impaired CD4(+) T cell function, particularly those with AIDS. To identify cryptococcal antigens that could serve as vaccine candidates by stimulating T cell responses, C. neoformans-reactive CD4(+) T cell hybridomas were generated by immunization of C57BL/6 mice and fusion of splenocytes with thymoma cells. The antigen that stimulated one of the hybridomas, designated P1D6, to produce IL-2 was purified to homogeneity by sequential anion exchange chromatography, hydrophobic interaction chromatography, and SDS/PAGE. Based on its apparent molecular mass of 98 kDa and mannosylation, the antigen of interest was named MP98. MP98 was N terminal-sequenced, and the gene encoding the protein was cloned and sequenced. Recombinant MP98, expressed in Saccharomyces cerevisiae, stimulated P1D6 to produce IL-2. Analysis of the derived 458-aa sequence of MP98 reveals an N-terminal cleavable signal sequence, a polysaccharide deacetylase domain found in fungal chitin deacetylases, and a serine/threonine-rich C-terminal region. Overall, there were 103 serine/threonine residues serving as potential O-linked glycosylation sites as well as 12 possible N-linked glycosylation sites. Thus, a C. neoformans mannoprotein has been characterized that stimulates T cell responses and has molecular properties of a chitin deacetylase.     

Guidance hypothesis with verbal feedback in learning a palpation skill

OBJECTIVE: To investigate whether a force application of a novel motor skill was simple or complex and to determine the appropriate level of feedback during training. The objective was to determine the effects of various amounts of knowledge of results (KR) on learning a novel skill that is frequently taught in chiropractic for the assessment of vertebral motor unit dysfunction. METHODS: Thirty-five active subjects were taught the novel skill of spring testing to a particular force range through 9 or 10 teaching sessions over a 2-week period (a school holiday limited some to only 9 sessions). To determine the particular force range, an initial phase of the study involved a licensed and practicing clinician performing motion palpation spring testing of the thoracic spine of a prone subject. The data from a total of 47 pushes throughout the thoracic spine were recorded, and the mean force and standard deviation were calculated. The second phase of the study used the obtained mean and standard deviation for teaching the force of prone thoracic spine motion palpation to 35 active subjects by administering spring testing to 35 passive subjects. The active subjects were randomly divided into 4 groups, with each receiving a varying amount of verbal feedback to move toward the target force of their learned skill. Each passive subject was laid prone on an instrumented adjusting table. Group 1 received the least amount of feedback while learning the novel skill. Groups 2 and 3 received more frequent, intermittent feedback while learning the skill, and group 4 received constant, frequent feedback during each of the 10 teaching sessions. All subjects returned within 2 weeks for 2 retention trials to determine the efficacy of the learned skill. RESULTS: The mean force determined was 143 N with a standard deviation of 14 N. Each subject was taught spring testing within this target range. The 2 final retention trials showed group 3 to have demonstrated the most targeted retention of the learned motor skill. These subjects exhibited the closest force range to the target for the motor skill learned and fewer changes in standard deviation compared with their acquisition trials and thus the highest retention. Group 4, receiving 100% feedback, demonstrated the most accurate spring testing during the acquisition trials, but the subjects did not effectively demonstrate when compared on acquisition and retention trials. CONCLUSION: The results of this study show data to be consistent with the guidance hypothesis in learning a novel motor skill. The constant KR feedback is beneficial for learning when used to reduce error during practice but detrimental when relied upon for retention and learning. These data suggest the necessity of using motor skill development learning theory in the teaching of chiropractic.     

Interventions for residents with dementia and their family and staff caregivers: evaluating the effectiveness of measures of outcomes in long-term care

This article describes six instruments developed for programs of research testing nursing interventions for individuals with dementia in Special Care Units and their family and staff caregivers. The Functional Abilities Checklist measures the functional abilities of residents with dementia. The Family Perceptions of Care Tool assesses family member satisfaction with care of the institutionalized relative with dementia. The Family Perceptions of Caregiving Role instrument evaluates stress experienced by family members of individuals with dementia related to their caregiving roles in long-term care settings. The Caregiver Stress Inventory and Staff Perceptions of Caregiving Role tools measure staff stress related to caring for residents with dementia. Finally, the Attitudes About Families Checklist assesses general staff attitudes about families of residents with dementia. Each instrument and its psychometric properties are described. The advantages of these instruments for research and clinical use with individuals with dementia are discussed.