Polyneuropathy associated with IgA monoclonal gammopathy of undetermined significance

Although polyneuropathies associated with IgM and IgG monoclonal gammopathies have been well described, polyneuropathy with IgA monoclonal gammopathy of undetermined significance (MGUS) is less commonly seen and has not been well studies. We reviewed the clinical and electrodiagnostic features of 5 such patients, and the sural nerve biopsy findings in 4 of them. One patient was diabetic, while 4 were free of other diagnoses commonly associated with neuropathy. Clinical presentations were varied. Electrodiagnostic and histological studies ranged from primary demyelination to primary axon loss to a mixed axonal/demyelinating picture. Three patients who were treated appeared to respond to prednisone or intravenous gamma globulin, despite clear clinical, electrodiagnostic, and histological differences. We conclude that the polyneuropathy associated with IgA MGUS is heterogeneous, similar to that in IgM and IgG MGUS. A trial of immunomodulating therapy appears to be warranted in such patients if the neuropathy is sufficiently servere. © 1993 John Wiley & Sons, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50156/1/880160113_ftp.pd

Time-Related Changes in Detrusor Overactivity in Awake Rats with Spinal Cord Injury Observed by Simultaneous Registrations of Intravesical and Intraabdominal Pressures

PurposeTo compare the physical characteristics of detrusor overactivity (DO) induced by intravesical infusion of saline in awake, sham rats and rats with chronic spinal cord injury (SCI), by simultaneous registrations of intravesical and intraabdominal pressures.MethodsMale Sprague-Dawley rats, normal or with a spinal vascular clip at the level of Th9, were investigated cystometrically 1 and 4 weeks after SCI. Intravesical pressure (IVP) and intraabdominal pressure (IAP) were recorded simultaneously to evaluate true DO. During the filling phase, the event of IVP rises, defined as increments that exceeded 2 cmH2O from baseline, were determined as DO according to the absence of simultaneous changes in IAP.ResultsAll SCI rats exhibited DO during the filling phase, which was not shown in sham rats. The frequency and pressure of DO had a tendency to decrease with time. The DO frequency of SCI rats after 4 weeks (0.9±0.2 min-1) was decreased compared with that after 1 week (2.1±0.4 min-1; P<0.05). The DO pressure of SCI rats after 4 weeks (8.4±1.9 cmH2O) was decreased compared with that after 1 week (11.6±2.9 cmH2O; P>0.05).ConclusionsCystometric studies in awake male SCI rats showed some significant changes in bladder function after SCI. All SCI rats exhibited DO during the filling phase, and showed different physical characteristics of DO over the course of time. The neurological basis of these time-related changes remains poorly understood, but may provide important prognostic information about long-term urological management in SCI patients

A model for the growth of mathematical specialties

A mathematical model for the growth of two coupled mathematical specialties, differential geometry and topology, is analyzed. The key variable is the number of theorems in use in each specialty. Obsolescences of theorems-in-use due to replacement by more general theorems introduces non-linear terms of the differential equations. The stability of stationary solutions is investigated. The phase portrait shows that the number of theorems in low-dimensional topology relative to those in differential geometry is increasing. The model is qualitatively consistent with the growth of publications in these two specialties, but does not give quantitative predictions, partly because we do not use an explicit solutions as a function of time and partly because only two specialties are used. The methods of analysis and some of the concepts can be extended to the development of more general and realistic models for the growth of specialties.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43670/1/11192_2005_Article_BF02021121.pd

Management of difficult cases in female urology and neurourology at the Reed M. Nesbit society meeting festschrift in honor of Edward J. McGuire, MD

This is a panel discussion of seven complex urologic cases in female urology and neurourology. Differences in diagnosis and management are discussed by this international panel of experts. Neurourol. Urodynam. 29:S2–S12, 2010. © 2010 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71363/1/20795_ftp.pd

Ultrasound confirmation of guidewire position may eliminate accidental arterial dilatation during central venous cannulation

<p>Abstract</p> <p>Background</p> <p>Ultrasound guidance during central line insertion has significantly reduced complications associated with this procedure and has led to it being incorporated as standard of care in many institutions. However, inadvertent arterial penetration and dilation remains a problem despite ultrasound guidance and can result in significant morbidity and even mortality. Dynamic ultrasound confirmation of guidewire position within the vein prior to dilation may help to prevent and even eliminate this feared complication.</p> <p>Methods</p> <p>A prospectively collected database of central line insertions for one author utilizing this novel technique was retrospectively reviewed for all incidents of arterial dilation over a period from September 2008 to January 2010.</p> <p>Results</p> <p>During the study period 53 central lines were inserted with no incidents of arterial dilation.</p> <p>Conclusions</p> <p>Ultrasound confirmation of guidewire position has the potential to reduce or eliminate the morbidity and mortality of arterial dilation during central line placement.</p

Muscle fiber branching -- difference between grafts in old and young rats

Large numbers of branched muscle fibers occur in the freely grafted rat extensor digitorum longus muscle. The ratio of branched/non-branched muscle fibers in grafts is much higher in old (24 months) than in young (4 months) host rats. Cross-age transplants show that the proportion of branched muscle fibers is related to the age of the grafted muscle and not to the age of the host. This is in contrast to mass and maximum isometric tension, in which the age of the host, rather than the age of the grafted muscle, is the determinant of the success of the muscle graft.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29138/1/0000179.pd

Sonographic and Clinical Features of Upper Extremity Deep Venous Thrombosis in Critical Care Patients

Background-Aim. Upper extremity deep vein thrombosis (UEDVT) is an increasingly recognized problem in the critically ill. We sought to identify the prevalence of and risk factors for UEDVT, and to characterize sonographically detected thrombi in the critical care setting. Patients and Methods. Three hundred and twenty patients receiving a subclavian or internal jugular central venous catheter (CVC) were included. When an UEDVT was detected, therapeutic anticoagulation was started. Additionally, a standardized ultrasound scan was performed to detect the extent of the thrombus. Images were interpreted offline by two independent readers. Results. Thirty-six (11.25%) patients had UEDVT and a complete scan was performed. One (2.7%) of these patients died, and 2 had pulmonary embolism (5.5%). Risk factors associated with UEDVT were presence of CVC [(odds ratio (OR) 2.716, P = 0.007)], malignancy (OR 1.483, P = 0.036), total parenteral nutrition (OR 1.399, P = 0.035), hypercoagulable state (OR 1.284, P = 0.045), and obesity (OR 1.191, P = 0.049). Eight thrombi were chronic, and 28 were acute. We describe a new sonographic sign which characterized acute thrombosis: a double hyperechoic line at the interface between the thrombus and the venous wall; but its clinical significance remains to be defined. Conclusion. Presence of CVC was a strong predictor for the development of UEDVT in a cohort of critical care patients; however, the rate of subsequent PE and related mortality was low

Brief Communication

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67313/2/10.1177_088307389801300308.pd

Distribution of scientific experts as recognized by peer consensus

Peer review plays an important role in maintaining the quality of science. Selection of peers is at the heart of the process by which science advances. Editors and others responsible for selecting a group of peers often rely on their position in a network by which experts in a field are linked to one another by bonds of common interest and recognized expertise. In this paper, we report one aspect of a study aimed at characterizing the structure of this network: the asymmetry of the fraction of experts receiving varying numbers of nominations as experts by peers. The distribution of such nominations is very skew, and we have found that a law of cumulative advantage provides the best theoretical approximation for the distribution of nominations, expecially when the overall pool of data is broken down into well-defined specialties.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43671/1/11192_2005_Article_BF02098005.pd

Systemwide Clinical Ultrasound Program Development: An Expert Consensus Model.

Clinical ultrasound (CUS) is integral to the practice of an increasing number of medical specialties. Guidelines are needed to ensure effective CUS utilization across health systems. Such guidelines should address all aspects of CUS within a hospital or health system. These include leadership, training, competency, credentialing, quality assurance and improvement, documentation, archiving, workflow, equipment, and infrastructure issues relating to communication and information technology. To meet this need, a group of CUS subject matter experts, who have been involved in institution- and/or systemwide clinical ultrasound (SWCUS) program development convened. The purpose of this paper was to create a model for SWCUS development and implementation