Local bone loss in patients with anti-citrullinated peptide antibody and arthralgia, evaluated with high-resolution peripheral quantitative computed tomography.

OBJECTIVE: To investigate bone changes in the metacarpophalangeal (MCP) joints of anti-citrullinated peptide antibody (ACPA)-positive patients with arthralgia, but not arthritis, compared to healthy controls. METHOD: Using a cross-sectional study design, patients were recruited from hospitals and private care rheumatologists, and controls from a test subject website. All subjects underwent medical history interview, clinical examination, and biochemical screening including ACPA. Patients with positive ACPA, arthralgia, and no rheumatic disease were included. Controls without a history or signs of rheumatological disease or positive ACPA were included. A 2.7-cm-long region around the second and third MCP joints was evaluated using high-resolution peripheral quantitative computed tomography with a voxel size of 82 µm. RESULTS: Twenty-nine ACPA-positive patients and 29 healthy controls were evaluated. Trabecular volumetric bone mineral density and bone volume fraction did not differ between the groups. In addition, the cortical bone was not affected in patients, as we found no difference in average cortical thickness and cortical bone area between the groups. In contrast, the trabeculae were significantly (p < 0.05) thinner in both second and third MCP heads compared with controls, whereas trabecular number and trabecular separation did not differ between the groups. No erosions were demonstrated and the number of non-specific breaks did not differ between the groups. CONCLUSION: Trabecular bone changes were observed in ACPA-positive patients with arthralgia compared with healthy controls. The results may reflect inflammatory up-regulated trabecular bone resorption leading to early bone loss before the onset of clinical arthritis.

Marine debris in harbour porpoises and seals from German waters.

Records of marine debris in and attached to stranded harbour porpoises (Phocoena phocoena), harbour seals (Phoca vitulina) and grey seals (Halichoerus grypus) were studied comprising information on 6587 carcasses collected along the German coast between 1990 and 2014, the decomposition state allowed for necropsy in 1622 cases. Marine debris items were recorded in 31 carcasses including 14 entanglements (5 harbour porpoises, 6 harbour seals, 3 grey seals) and 17 cases of ingestion (4 harbour porpoises, 10 harbour seals, 3 grey seals). Objects comprised general debris (35.1%) and fishing related debris (64.9%). Injuries associated with marine debris included lesions, suppurative ulcerative dermatitis, perforation of the digestive tract, abscessation, suppurative peritonitis and septicaemia. This study is the first investigation of marine debris findings in all three marine mammal species from German waters. It demonstrates the health impacts marine debris can have, including severe suffering and death. The results provide needed information on debris burdens in the North and Baltic Seas for implementing management directives, such as the Marine Strategy Framework Directive (MSFD).

A Unique Model for ONSD Part II: Inter/Intra-operator Variability.

OBJECTIVE: To evauluate our novel ultrasound model for measurement of optic nerve sheath diameter (ONSD) and determine the intra- and inter-operator variability associated with this technique. METHODS: We conducted ten measurements of ONSD per model amongst eight different models with a single experienced operator to examine intra-operator variability. Similarly, we had seven different operators measure the OSND twice in eight different models, in order to determine inter-operator variability analyzed with a three level linear statistical model. RESULTS: For intra-operator variability, the intra-cluster correlation coefficients for the experienced and novice operators were 0.643 and 0.453 respectively. This displayed improvement in intra-operator variability with experience. The inter-cluster correlation coefficient was 0 for the group of novice operators, indicating negligible difference amongst multiple operators in measuring any given model of ONSD. A strong, statistically significant, linear relationship between the actual model disc size and the ultrasound ONSD measures was identified, implying the reliability of the images produced by our novel model. CONCLUSIONS: Utilizing a novel model for ONSD ultrasonography, we have determined the intraoperator reliability of ONSD measurement to be moderate, with no appreciable difference amongst multiple operators. Improvement in measurement reliability has been demonstrated between expert and novice operators with our model, indicating the potential benefit of simulation platforms for teaching the technique of ONSD ultrasound.

Roughness Perception in Virtual Textures.

Haptic devices allow the production of virtual textured surfaces for psychophysical experiments. Some studies have shown inconsistencies between virtual and real textures with respect to their psychophysical functions for roughness, leading to speculation that virtual textures differ in some way from real ones. We have determined the psychophysical function for roughness using textures rendered with a high-fidelity magnetic levitation haptic device. A constraint surface algorithm was used to simulate the motion of a spherical probe over trapezoidal gratings and randomly dithered cones. The shape of the psychophysical functions for roughness is consistent between subjects but varies with changes in texture and probe geometry. For dithered cones, inverted "U"-shaped functions were found nearly identical, in maxima and curvature, to those in the literature for real textures with similar geometry.

Diagnostic accuracy of 3D time-of-flight MR angiography compared with digital subtraction angiography for follow-up of coiled intracranial aneurysms: influence of aneurysm size.

BACKGROUND AND PURPOSE: 3D time-of-flight MR angiography (3D TOF MRA) may be used as noninvasive alternative to digital subtraction angiography (DSA) for the follow-up of patients with intracranial aneurysms treated with Guglielmi detachable coils (GDCs). We aimed to determine the influence of aneurysm size and location on diagnostic accuracy of 3D TOF MRA for follow-up of intracranial aneurysms treated with GDCs. MATERIALS AND METHODS: Two hundred and one 3D TOF MRAs in 127 consecutive patients with 136 aneurysms were compared with DSA as standard of reference. Sensitivity and specificity of 3D TOF MRA for detection of residual or reperfusion of the aneurysms was calculated with regard to aneurysm size and location. RESULTS: Overall sensitivity and specificity of MRA was 88.5% and 92.9%, respectively. Sensitivity was lower for aneurysms

The A20R protein is a stoichiometric component of the processive form of vaccinia virus DNA polymerase.

In vitro analysis of the catalytic DNA polymerase encoded by vaccinia virus has demonstrated that it is innately distributive, catalyzing the addition of <10 nucleotides per primer-template binding event in the presence of 8 mM MgCl(2) or 40 mM NaCl (W. F. McDonald and P. Traktman, J. Biol. Chem. 269:31190-31197, 1994). In contrast, cytoplasmic extracts isolated from vaccinia virus-infected cells contain a highly processive form of DNA polymerase, able to catalyze the replication of a 7-kb template per binding event under similar conditions. To study this holoenzyme, we were interested in purifying and characterizing the vaccinia virus processivity factor (VPF). Our previous studies indicated that VPF is expressed early after infection and has a native molecular mass of approximately 48 kDa (W. F. McDonald, N. Klemperer, and P. Traktman, Virology 234:168-175, 1997). Using these criteria, we established a six-step chromatographic purification procedure, in which a prominent approximately 45-kDa band was found to copurify with processive polymerase activity. This species was identified as the product of the A20 gene. By use of recombinant viruses that direct the overexpression of A20 and/or the DNA polymerase, we verified the physical interaction between the two proteins in coimmunoprecipitation experiments. We also demonstrated that simultaneous overexpression of A20 and the DNA polymerase leads to a specific and robust increase in levels of processive polymerase activity. Taken together, we conclude that the A20 gene encodes a component of the processive DNA polymerase complex. Genetic data that further support this conclusion are presented in the accompanying report, which documents that temperature-sensitive mutants with lesions in the A20 gene have a DNA(-) phenotype that correlates with a deficit in processive polymerase activity (A. Punjabi et al, J. Virol. 75:12308-12318, 2001).

Clustered charge-to-alanine mutagenesis of the vaccinia virus A20 gene: temperature-sensitive mutants have a DNA-minus phenotype and are defective in the production of processive DNA polymerase activity.

Although the vaccinia virus DNA polymerase is inherently distributive, a highly processive form of the enzyme exists within the cytoplasm of infected cells (W. F. McDonald, N. Klemperer, and P. Traktman, Virology 234:168-175, 1997). In the accompanying report we outline the purification of the 49-kDa A20 protein as a stoichiometric component of the processive polymerase complex (N. Klemperer, W. McDonald, K. Boyle, B. Unger, and P. Traktman, J. Virol. 75:12298-12307, 2001). To complement this biochemical analysis, we undertook a genetic approach to the analysis of the structure and function of the A20 protein. Here we report the application of clustered charge-to-alanine mutagenesis of the A20 gene. Eight mutant viruses containing altered A20 alleles were isolated using this approach; two of these, tsA20-6 and tsA20-ER5, have tight temperature-sensitive phenotypes. At the nonpermissive temperature, neither virus forms macroscopic plaques and the yield of infectious virus is <1% of that obtained at the permissive temperature. Both viruses show a profound defect in the accumulation of viral DNA at the nonpermissive temperature, although both the A20 protein and DNA polymerase accumulate to wild-type levels. Cytoplasmic extracts prepared from cells infected with the tsA20 viruses show a defect in processive polymerase activity; they are unable to direct the formation of RFII product using a singly primed M13 template. In sum, these data indicate that the A20 protein plays an essential role in the viral life cycle and that viruses with A20 lesions exhibit a DNA(-) phenotype that is correlated with a loss in processive polymerase activity as assayed in vitro. The vaccinia virus A20 protein can, therefore, be considered a new member of the family of proteins (E9, B1, D4, and D5) with essential roles in vaccinia virus DNA replication.

Perioperative management of selected endocrine disorders.

Anesthesiologists routinely encounter patients with endocrine disorders. Good perioperative outcome depends on preoperative identification, risk stratification and optimization of the patients' endocrinopathies and their sequelae; intraoperative control of metabolic and physiological parameters; and appropriate postoperative pain management, stress modulation, and evaluation of neurological, cardiovascular, and renal function.

Quantitative gram stain interpretation criteria used by microbiology laboratories in Alberta, Canada.

Microbiology laboratories in Alberta, Canada, were surveyed to determine the quantitative interpretive criteria used to routinely read and report Gram stains. There was a wide variability in the quantitative reporting criteria cited for both cells and bacteria, with only 11 of 32 (34.4%) laboratories surveyed using the criteria recommended by the external proficiency-testing program. Lack of standardized criteria not only poses a problem in the grading of proficiency testing results but may also impact the quality of patient care.

Unsafe sleep practices and an analysis of bedsharing among infants dying suddenly and unexpectedly: results of a four-year, population-based, death-scene investigation study of sudden infant death syndrome and related deaths.

BACKGROUND: Prone sleep and unsafe sleep surfaces increase the risk of sudden infant death. Recent epidemiologic studies also suggest that when an infant's head or face is covered by bedding, or when a sleep surface is shared with others, the risk of dying increases. The inference of a causal role for these risk factors is supported by physiologic studies and by the consistent finding that fewer infants die when risk factors are reduced. The prevalence of most of these risk factors in infant deaths in the United States is uncertain. OBJECTIVE: To describe the prevalence of several important risk factors related to sleep practices among a defined population of infants dying suddenly and unexpectedly. METHODS: In this population-based study, we retrospectively reviewed death-scene information and medical examiners' investigations of deaths in the city of St Louis and St Louis County between January 1, 1994 and December 31, 1997. Because of the potential for diagnostic overlap, all deaths involving infants <2 years old with the diagnoses of sudden infant death syndrome (SIDS), accidental suffocation, or cause undetermined were included. RESULTS: The deaths of 119 infants were studied. Their mean age was 109.3 days (range: 6-350). The diagnoses were SIDS in 88 deaths, accidental suffocation in 16, and undetermined in 15. Infants were found prone in 61.1% of cases and were found on a sleep surface not designed for infants in 75.9%. The head or face was covered by bedding in 29.4%. A shared sleep surface was the site of death in 47.1%. Only 8.4% of deaths involved infants found nonprone and alone, with head and face uncovered. CONCLUSIONS: Using detailed death-scene descriptions, we found that similar unsafe sleeping practices occurred in the large majority of cases diagnosed as SIDS, accidental suffocation, and cause undetermined. Considering these diagnoses together may be useful in public health campaigns during a time when there may be diagnostic overlap. Regardless of the diagnosis, recommendations that infants sleep supine on firm sleep surfaces that lessen the risk of entrapment or head covering have the potential to save many lives. Campaigns are needed to heighten awareness of these messages and of the risks of dangerous bedsharing.

A novel type of carbohydrate-protein linkage region in the tyrosine-bound S-layer glycan of Thermoanaerobacterium thermosaccharolyticum D120-70.

The surface-layer (S-layer) protein of Thermoanaerobacterium thermosaccharolyticum D120-70 contains glycosidically linked glycan chains with the repeating unit structure -->4)[alpha-D-Galp-(1-->2)]-alpha-L-Rhap-(1-->3)[beta-D-Glcp-(1--> 6)] -beta-D-Manp-(1-->4)-alpha-L-Rhap-(1-->3)-alpha-D-Glcp-(1--> . After proteolytic degradation of the S-layer glycoprotein, three glycopeptide pools were isolated, which were analyzed for their carbohydrate and amino-acid compositions. In all three pools, tyrosine was identified as the amino-acid constituent, and the carbohydrate compositions corresponded to the above structure. Native polysaccharide PAGE showed the specific heterogeneity of each pool. For examination of the carbohydrate-protein linkage region, the S-layer glycan chain was partially hydrolyzed with trifluoroacetic acid. 1D and 2D NMR spectroscopy, including a novel diffusion-edited difference experiment, showed the O-glycosidic linkage region beta-D-glucopyranose-->O-tyrosine. No evidence was found of additional sugars originating from a putative core region between the glycan repeating units and the S-layer polypeptide. For the determination of chain-length variability in the S-layer glycan, the different glycopeptide pools were investigated by matrix-assisted laser desorption ionization-time of flight mass spectrometry, revealing that the degree of polymerization of the S-layer glycan repeats varied between three and 10. All masses were assigned to multiples of the repeating units plus the peptide portion. This result implies that no core structure is present and thus supports the data from the NMR spectroscopy analyses. This is the first observation of a bacterial S-layer glycan without a core region connecting the carbohydrate moiety with the polypeptide portion.

Elucidating the essential role of the A14 phosphoprotein in vaccinia virus morphogenesis: construction and characterization of a tetracycline-inducible recombinant.

We have previously reported the construction and characterization of vindH1, an inducible recombinant in which expression of the vaccinia virus H1 phosphatase is regulated experimentally by IPTG (isopropyl-beta-D-thiogalactopyranoside) (35). In the absence of H1 expression, the transcriptional competence and infectivity of nascent virions are severely compromised. We have sought to identify H1 substrates by characterizing proteins that are hyperphosphorylated in H1-deficient virions. Here, we demonstrate that the A14 protein, a component of the virion membrane, is indeed an H1 phosphatase substrate in vivo and in vitro. A14 is hyperphosphorylated on serine residues in the absence of H1 expression. To enable a genetic analysis of A14's function during the viral life cycle, we have adopted the regulatory components of the tetracycline (TET) operon and created new reagents for the construction of TET-inducible vaccinia virus recombinants. In the context of a virus expressing the TET repressor (tetR), insertion of the TET operator between the transcriptional and translational start sites of a late viral gene enables its expression to be tightly regulated by TET. We constructed a TET-inducible recombinant for the A14 gene, vindA14. In the absence of TET, vindA14 fails to form plaques and the 24-h yield of infectious progeny is reduced by 3 orders of magnitude. The infection arrests early during viral morphogenesis, with the accumulation of large numbers of vesicles and the appearance of "empty" crescents that appear to adhere only loosely to virosomes. This phenotype corresponds closely to that observed for an IPTG-inducible A14 recombinant whose construction and characterization were reported while our work was ongoing (47). The consistency in the phenotypes seen for the IPTG- and TET-inducible recombinants confirms the efficacy of the TET-inducible system and reinforces the value of having a second, independent system available for generating inducible recombinants.

Effects of restructuring on the performance of microbiology laboratories in Alberta.

OBJECTIVE: To evaluate the error rates of organism identification and antibiotic susceptibility proficiency testing challenges before, during, and after microbiology laboratory restructuring in Alberta. METHODS: Alberta Health substantially reduced and redistributed laboratory funds to the regional health authorities in 1995, forcing a dramatic restructure of services. Many rural hospitals expanded their microbiology test menus, and urban centers consolidated microbiology testing into a centralized high-volume laboratory. The Laboratory Proficiency Testing Program of the College of Physicians and Surgeons of Alberta mailed regular test profile surveys to microbiology laboratories during the restructure period to determine the type and extent of changes in services. Based on the types of tests and the extent of analysis being done, most rural B-level and some C-level laboratories were reclassified to the A level. The Laboratory Proficiency Testing Program reviewed the error rates of proficiency challenges based on the performance of different levels of laboratories before and after the period of restructure. RESULTS: Overall performance has improved according to the number of errors documented on identification and susceptibility challenges for laboratories that remained at the same classification (ie, A or C). The number of major identification errors for laboratories that were reclassified increased, but the rate of major susceptibility errors decreased. More reclassified laboratories do not have dedicated registered technologist(s) who perform microbiology testing and are not supervised by an on-site pathologist and/or medical microbiologist compared with laboratories that remained at the same classification. CONCLUSIONS: Microbiology laboratory restructuring will have adverse effects on the quality of complex testing if experienced technologists are not retained and services are not medically supervised.

[Differential diagnosis of space-occupying adrenal masses]. / Differentialdiagnose raumfordernder Prozesse der Nebennieren.

Computed tomography (CT) and magnetic resonance (MR) imaging are first line modalities in the evaluation of patients with adrenal gland masses, and have the potential to be very accurate for the localization of adrenal gland masses in patients with diseases associated with hyperfunctioning conditions of the adrenal gland. Both CT and MR imaging allow a specific diagnosis of acute adrenal hemorrhage, adrenal myelolipoma, and adrenal cysts. CT is also helpful in the assessment of patients with Addison's disease, particularly the subacute form secondary to granulomatous diseases. Quantitative evaluation of adrenal masses on unenhanced CT scans and/or qualitative analysis on chemical-shift MR imaging have been shown to be accurate in distinguishing adrenal adenomas from non-adenomas. Attenuation of 11 HE or less on unenhanced CT scans and/or signal loss on opposed phase MR images indicate adenoma with a high specificity and acceptable sensitivity. More recently, delayed-enhanced CT has yielded higher sensitivity and specificity values in distinguishing between adrenal adenomas and non-adenomas than both unenhanced CT and chemical-shift MR imaging do. On delayed-enhanced CT scans, adrenal adenomas exhibit a greater washout of contrast material than do adrenal non-adenomas. Therefore, adrenal non-adenomas have significantly higher attenuation than adenomas on delayed-enhanced CT scans obtained at several arbitrarily chosen time points (3-60 min) after the initiation of contrast material administration.

[Radiologic staging of renal cell carcinoma]. / Radiologisches Staging des Nierenzellkarzinoms.

The routine staging work-up for renal cancer includes a contrast-enhanced multiphasic spiral CT and a chest radiograph. If there is doubt regarding the presence and extent of (supradiaphragmatic) IVC thrombus, MR imaging should be performed. Dynamic contrast-enhanced MR imaging should be used in place of CT in any patient with severe renal dysfunction, symptomatic polycystic kidney disease, or a history of allergy to iodinated contrast media. Cavography is no longer needed in the era of (adaptive array detector) spiral CT and MR venography.

[Digital 3D rotational angiography for the preoperative and preinterventional clarification of cerebral arterial aneurysms]. / Digitale 3D-Rotationsangiographie zur präoperativen und präinterventionellen Abklärung von Hirnarterienaneurysmen.

OBJECTIVE: Does the recently introduced 3D angiography provide additional information beyond standard angiography (DSA) for the diagnosis of cerebral aneurysms? METHODS: During a 3-months period DSA and 3D-angiography were performed in 40 patients harbouring a total of 49 aneurysms. Vascular regions that presented an aneurysm diagnosed by DSA were reevaluated by 3D-angiography. RESULTS: In two patients, vessel-loops previously described as aneurysms by DSA could be identified by 3D-angiography. In one patient, an aneurysm was diagnosed that could not be detected by DSA. In another case, the definitive diagnosis of an aneurysm was obtained only with 3D-angiography. In one patient, an aneurysm was diagnosed that could not be detected by DSA. In another case, the diagnosis of an aneurysm was obtained only with 3D-angiography. In two cases, aneurysms could be definitively excluded by 3D-angiography, whereas in another aneurysm a vessel originating from this lesion was identified. The size of the aneurysms measured by both methods was identical. CONCLUSIONS: Multiple projections of 3D-angiography provide a better evaluation of the anatomic situation regarding the base of the aneurysm as well as the relationship of an aneurysm to neighbouring vessels. Further, an exact differentiation between a vessel loop and an aneurysm can be made. Therefore, 3D-angiography is a valuable tool when used in conjunction with DSA.