Use of complementary and alternative medicine in an urban county hospital epilepsy clinic.

We examined self-reported complementary and alternative medicine (CAM) use among a largely indigent population with epilepsy. Overall CAM use was 70%, with the most frequently reported complementary and alternative medicines (CAMs) being medical marijuana (33%), prayer/spirituality (31%), meditation (19%), vitamins (19%), and stress management (16%). Forty-four percent of patients reported improved seizure control with CAMs. Stress management accounted for perceived seizure reduction in 74%, followed by marijuana (54%), prayer (49%), and yoga (42%). Among the most commonly used and helpful CAMs, stress management was not associated with specific demographic or clinical variables; marijuana use was significantly associated with lower age (users=35.2±10 years vs. nonusers=41.6±12; p<0.01) and lower income (under $15,000 40% use vs. 14% over $15,000; p<0.05); and prayer was significantly associated with female gender (male=21% vs. female=45%; p<0.01) and Black ethnicity (Black=55% vs. Hispanic=30% vs. White=23%; p<0.05). Taken together, our study was notable for the high rate of CAM utilization in a largely indigent population, with high rates of perceived efficacy among several CAM modalities.

A pilot study investigating the use of at-home, web-based questionnaires compiling patient-reported outcome measures following total hip and knee replacement surgeries.

Patient-reported outcome measures (PROMs) are used routinely in NHS. Traditional pen-and-paper questionnaire collection can be time-consuming for both patients and clinic staff. The purpose of the current study was to determine whether a web-based PROMs system has the potential to provide satisfactory patient compliance and whether compiled data are equivalent to pen-and-paper PROMs data. A series of 82 patients who had joint replacement surgery was identified. Each patient was contacted by letter to register on the myClinicalOutcomes.co.uk website and to follow the instructions to render an Oxford score. A second request was sent to those failing to initially register. Telephone contact was then made with non-responders to identify the reason for failed registration. Successfully collated online Oxford scores were compared with previously recorded pen-and-paper scores for each patient from a prospectively updated database. Of the 82 patients identified, 61 (74%) received a letter or were otherwise contacted by telephone. Of these, 27 (44%) patients confirmed that they had access to the Internet. A total of 21 complete sets of data were collected. On review, the available secure online Oxford outcome scores demonstrated a mean of 30.1 (SD 11.4, range: 9-47). This mean score was comparable to the pen-and-paper database mean score of 29.1 (SD 11.8, range: 9-48) for the respective patients. Of the 27 respondents with Internet access, 21 (78%) produced complete scores that were available for real-time review. Available online scores were comparable to those collected via traditional means. With increased Internet availability and improved communication, remote web-based collection of patient reported outcomes may facilitate enhanced and efficient follow-up of patients.

The incidence of infrapatellar plicae in the elderly Welsh population.

There are several studies reporting the incidence of suprapatellar, medial, and lateral plicae, but there is very limited information regarding the incidence of the infrapatellar plica. The purpose of our study was to record the incidence of infrapatellar plicae in the elderly Welsh population suffering from knee osteoarthritis. A prospective study was performed and 90 knees with severe osteoarthritis of the knee joint (Kellgren-Lawrence type III and IV) were investigated during total knee arthroplasty surgery. Documentation was performed at every total knee replacement surgery for the length of the study. Knee replacement was performed by one senior surgeon. Infrapatellar plica was investigated by a medial parapatellar approach and was classified into five types according to Kim's classification. The overall incidence of infrapatellar plicae was 37.7%. The most common type of plicae was the separate type (23.3%). There was no significant difference found between male and female patients. The fenestra type was the least common (2.22%). The incidence of infrapatellar plicae in the elderly Welsh population suffering from knee osteoarthritis was significantly lower when compared to a study that recorded the incidence of infrapatellar plica in young patients. Possibly, the degenerative changes of the knee joint can cause the resorption of the infrapatellar plica, thus decreasing its incidence in the elderly population.

Hip pain and pseudo-lengthening of the leg due to iliopsoas haematoma following implantation of an uncemented component in acetabular cotyloplasty technique.

We report early symptomatic (groin pain and apparent limb lengthening) findings in our 12 consecutive patients who underwent total hip replacements using a cementless acetabular cotyloplasty technique. This report is the first in the literature to mention such an early complication in a large number of patients and also to describe early detection and treatment in these cases. During the period of January 2007 to December 2010, 12 patients (seven female, five male) with dysplastic hip underwent total hip arthroplasty. The mean age of the patients was 57 years (range 52-61 years) and the mean follow-up time was 18 months (12-36 months). A cotyloplasty technique was performed and uncemented acetabular and femoral components were implanted in all these 12 patients. All patients were reviewed postoperatively for clinical and radiographic assessment at six weeks, three months, six months, and one year, and then annually thereafter. During the first one to two months (mean time 22 ± 16 days), all patients complained of a constant pain in the groin that started in the early postoperative period. A pseudo lengthening of the operated hip and pelvic tilt was found on clinical examination at the three-month follow-up. The True length did not reveal a significant leg length discrepancy. Hip pain, pseudo lengthening, and pelvic tilt resolved within 123 ± 17 days post-op. A cotyloplasty technique using an uncemented acetabular implant can cause an intrapelvic hematoma of the iliopsoas muscle giving rise to temporary groin pain, pseudo lengthening on the operated side, and gait disturbances to the patient in the early postoperative period. Symptoms resolved completely in all of our cases. Iliopsoas physiotherapy could be useful and should be encouraged during the symptomatic period. Patients have to be informed during consenting and reassured about this symptomatology. Awareness of this likely complication would help surgeons to detect the problem and initiate treatment early.

Effects of age and body mass on development of diving capabilities of gray seal pups: costs and benefits of the postweaning fast.

Development of adequate diving capabilities is crucial for survival of seal pups and may depend on age and body size. We tracked the diving behavior of 20 gray seal pups during their first 3 mo at sea using satellite relay data loggers. We employed quantile analysis to track upper limits of dive duration and percentage time spent diving, and lower limits of surface intervals. When pups first left the breeding colony, extreme (ninety-fifth percentile) dive duration and percentage time spent diving were positively correlated with age, but not mass, at departure. Extreme dive durations and percentage time spent diving peaked at [Formula: see text] d of age at values comparable with those of adults, but were not sustained. Greater peaks in extreme percentage time spent diving occurred in pups that had higher initial values, were older at their peak, and were heavier at departure. Pups that were smaller and less capable divers when they left the colony improved extreme dive durations and percentage time spent diving more rapidly, once they were at sea. Minimum survival time correlated positively with departure mass. Pups that were heavier at weaning thus benefitted from being both larger and older at departure, but smaller pups faced a trade-off. While age at departure had a positive effect on early dive performance, departure mass impacted on peak percentage time spent diving and longer-term survival. We speculate that once small pups have attained a minimum degree of physiological development to support diving, they would benefit by leaving the colony when younger but larger to maximize limited fuel reserves, rather than undergoing further maturation on land away from potential food resources, because poor divers may be able to "catch up" once at sea.

TMS1/ASC: the cancer connection.

TMS1/ASC is a bipartite protein comprising two protein-protein interaction domains, a pyrin domain (PYD) and a caspase recruitment domain (CARD). Proteins containing these domains play pivotal roles in regulating apoptosis and immune response pathways, and mutations in a number of PYD- and CARD-containing proteins have been linked to autoinflammatory diseases and cancer. Indeed, one of the ways in which TMS1/ASC was identified was as a target of methylation-mediated silencing in breast cancer cells. This review discusses the mounting evidence supporting a correlation between the silencing of TMS1/ASC expression and cancer. In addition, it addresses the reported functions of TMS1/ASC that include apoptosis, activation of inflammatory caspases and regulation of NF-kappa B, and discusses the potential ways in which loss of TMS1/ASC contributes to carcinogenesis.

Ventricular arrhythmia vulnerability in cardiomyopathic mice with homozygous mutant Myosin-binding protein C gene.

BACKGROUND: Homozygous mutant mice expressing a truncated form of myosin-binding protein C (MyBP-C(t/t)) develop severe dilated cardiomyopathy, whereas the heterozygous mutation (MyBP-C(t/+)) causes mild hypertrophic cardiomyopathy. Adult male MyBP-C(t/t) and MyBP-C(t/+) mice were evaluated for arrhythmia vulnerability with an in vivo electrophysiology study. METHODS AND RESULTS: Surface ECGs were obtained for heart rate, rhythm, and conduction intervals. Atrial, atrioventricular, and ventricular conduction parameters and refractoriness were assessed in 22 MyBP-C(t/t), 10 MyBP-C(t/+), and 17 wild-type MyBP-C(+/+) mice with endocardial pacing and intracardiac electrogram recording. Arrhythmia induction was attempted with standardized programmed stimulation at baseline and with isoproterenol. Heart rate variability and ambient arrhythmia activity were assessed with telemetric ECG monitors. Quantitative histological characterization was performed on serial sections of excised hearts. MyBP-C(t/t) and MyBP-C(t/+) mice have normal ECG intervals and sinus node, atrial, and ventricular conduction and refractoriness. Ventricular tachycardia was reproducibly inducible in 14 of 22 MyBP-C(t/t) mice (64%) during programmed stimulation, compared with 2 of 10 MyBP-C(t/+) mice (20%) and 0 of 17 wild-type controls (P<0.001). Ventricular ectopy was present only in MyBP-C(t/t) mice during ambulatory ECG recordings. There were no differences in heart rate variability parameters. Interstitial fibrosis correlated with genotype but did not predict arrhythmia susceptibility within the MyBP-C(t/t) group. CONCLUSIONS: MyBP-C(t/t) mice, despite prominent histopathology and ventricular dysfunction, exhibit normal conduction and refractoriness, yet are vulnerable to ventricular arrhythmias. Somatic influences between genetically identical mutant mice most likely account for variability in arrhythmia susceptibility. A sarcomeric protein gene mutation leads to a dilated cardiomyopathy and ventricular arrhythmia vulnerability phenotype.

The effects of propofol on the contractility of failing and nonfailing human heart muscles.

We determined the direct effects of propofol on the contractility of human nonfailing atrial and failing atrial and ventricular muscles. Atrial and ventricular trabecular muscles were obtained from the failing human hearts of transplant patients or from nonfailing hearts of patients undergoing coronary artery bypass surgery. Isometric contraction variables were recorded before and after propofol was added to the bath in concentrations between 0.056 and 560 microM. The effects of propofol were compared with its commercial vehicle intralipid. To test beta-adrenergic effects in the presence of propofol, 1 microM isoproterenol was added at the end of each experiment. To determine the cellular mechanisms responsible for the actions of propofol, we examined its effects on actomyosin ATPase activity and sarcoplasmic reticulum (SR) Ca(2+) uptake in nonfailing atrial tissues. Propofol caused a concentration-dependent decrease in maximal developed tension in all muscles, which became significant (P < 0.05) at concentrations exceeding the clinical range (> or =56 microM). Isoproterenol restored contractility to the level achieved before exposure to propofol (P > 0.05 compared with baseline). Failing ventricular muscle exposed to propofol exhibited somewhat diminished ability to recover contractility in response to isoproterenol (P < 0.05 versus failing muscle exposed to intralipid only). Propofol induced a concentration-dependent decrease in the uptake of Ca(2+) into SR vesicles. At the same time, in the presence of 56 microM propofol, the Ca(2+)-activated actomyosin ATPase activity was shifted leftward, demonstrating an increase in myofilament sensitivity to Ca(2+). We conclude that propofol exerts a direct negative inotropic effect in nonfailing and failing human myocardium, but only at concentrations larger than typical clinical concentrations. Negative inotropic effects are reversible with beta-adrenergic stimulation. The negative inotropic effect of propofol is at least partially mediated by decreased Ca(2+) uptake into the SR; however, the net effect of propofol on contractility is insignificant at clinical concentrations because of a simultaneous increase in the sensitivity of the myofilaments to activator Ca(2+).

Comparison of two murine models of familial hypertrophic cardiomyopathy.

Although sarcomere protein gene mutations cause familial hypertrophic cardiomyopathy (FHC), individuals bearing a mutant cardiac myosin binding protein C (MyBP-C) gene usually have a better prognosis than individuals bearing beta-cardiac myosin heavy chain (MHC) gene mutations. Heterozygous mice bearing a cardiac MHC missense mutation (alphaMHC(403/+) or a cardiac MyBP-C mutation (MyBP-C(t/+)) were constructed as murine FHC models using homologous recombination in embryonic stem cells. We have compared cardiac structure and function of these mouse strains by several methods to further define mechanisms that determine the severity of FHC. Both strains demonstrated progressive left ventricular (LV) hypertrophy; however, by age 30 weeks, alphaMHC(403/+) mice demonstrated considerably more LV hypertrophy than MyBP-C(t/+) mice. In older heterozygous mice, hypertrophy continued to be more severe in the alphaMHC(403/+) mice than in the MyBP-C(t/+) mice. Consistent with this finding, hearts from 50-week-old alphaMHC(403/+) mice demonstrated increased expression of molecular markers of cardiac hypertrophy, but MyBP-C(t/+) hearts did not demonstrate expression of these molecular markers until the mice were >125 weeks old. Electrophysiological evaluation indicated that MyBP-C(t/+) mice are not as likely to have inducible ventricular tachycardia as alphaMHC(403/+) mice. In addition, cardiac function of alphaMHC(403/+) mice is significantly impaired before the development of LV hypertrophy, whereas cardiac function of MyBP-C(t/+) mice is not impaired even after the development of cardiac hypertrophy. Because these murine FHC models mimic their human counterparts, we propose that similar murine models will be useful for predicting the clinical consequences of other FHC-causing mutations. These data suggest that both electrophysiological and cardiac function studies may enable more definitive risk stratification in FHC patients.

Diurnal and seasonal variations in the duration and depth of the longest dives in southern elephant seals (Mirounga leonina): possible physiological and behavioural constraints.

This study seeks to understand how the physiological constraints of diving may change on a daily and seasonal basis. Dive data were obtained from southern elephant seals (Mirounga leonina) from South Georgia using satellite relay data loggers. We analysed the longest (95th percentile) dive durations as proxies for physiological dive limits. A strong, significant relationship existed between the duration of these dives and the time of day and week of year in which they were performed. The depth of the deepest dives also showed a significant, but far less consistent, relationship with local time of day and season. Changes in the duration of the longest dives occurred irrespective of their depth. Dives were longest in the morning (04:00-12:00 h) and shortest in the evening (16:00-00:00 h). The size of the fluctuation varied among animals from 4.0 to 20.0 min. The daily pattern in dive depth was phase-shifted in relation to the diurnal rhythm in dive duration. Dives were deeper at midday and shallower around midnight. Greater daily changes in duration occurred in seals feeding in the open ocean than in those foraging on the continental shelf. The seasonal peak in the duration of the longest dives coincided with austral midwinter. The size of the increase in dive duration from autumn/spring to winter ranged from 11.5 to 30.0 min. Changes in depth of the longest dives were not consistently associated with particular times of year. The substantial diurnal and seasonal fluctuations in maximum dive duration may be a result of changes in the physiological capacity to remain submerged, in addition to temporal changes in the ecological constraints on dive behaviour. We speculate about the role of melatonin as a hormonal mediator of diving capability.

Activation of a caspase-9-mediated apoptotic pathway by subcellular redistribution of the novel caspase recruitment domain protein TMS1.

Genetic and epigenetic alterations affecting proteins involved in apoptosis can contribute to the establishment and progression of cancer. Recently, our laboratory has isolated a novel gene, TMS1, that is aberrantly methylated and silenced in a significant proportion of human breast cancers. TMS1 contains a caspase recruitment domain (CARD), suggesting a role in caspase-mediated cell death. In the present study, we characterize the participation of TMS1 in apoptosis and examine the subcellular localization of the protein. Inducible expression of TMS1 inhibited cellular proliferation and induced DNA fragmentation in a time-dependent manner. These apoptotic events were blocked by the general caspase inhibitor, Z-VAD-fmk. The ability of TMS1 to trigger apoptosis was also suppressed by a dominant negative form of caspase-9 but not by a dominant negative form of caspase-8, indicating that TMS1 functions through activation of caspase-9. Unlike a number of other CARD-containing proteins, TMS1 did not activate nuclear factor kappaB-dependent transcription, consistent with a proapoptotic role for TMS1 in death signaling pathways. Timed localization studies revealed that TMS1-induced apoptosis was accompanied by the redistribution of TMS1 from the cytoplasm to perinuclear spherical structures. Whereas the apoptotic activity of TMS1 was blocked by caspase inhibition, the formation of TMS1-containing subcellular structures was not, suggesting that the redistribution of TMS1 precedes caspase activation. Both the proapoptotic activity of TMS1 and aggregate formation were dependent on the CARD. In summary, the data indicate that TMS1-induced apoptosis proceeds through a CARD-dependent aggregation step followed by activation of a caspase-9-mediated pathway.

TMS1, a novel proapoptotic caspase recruitment domain protein, is a target of methylation-induced gene silencing in human breast cancers.

Gene silencing associated with aberrant methylation of promoter region CpG islands is an acquired epigenetic alteration that serves as an alternative to genetic defects in the inactivation of tumor suppressor and other genes in human cancers. The hypothesis that aberrant methylation plays a direct causal role in carcinogenesis hinges on the question of whether aberrant methylation is sufficient to drive gene silencing. To identify downstream targets of methylation-induced gene silencing, we used a human cell model in which aberrant CpG island methylation is induced by ectopic expression of DNA methyltransferase. Here we report the isolation and characterization of TMS1 (target of methylation-induced silencing), a novel CpG island-associated gene that becomes hypermethylated and silenced in cells overexpressing DNA cytosine-5-methyltransferase-1. We also show that TMS1 is aberrantly methylated and silenced in human breast cancer cells. Forty percent (11 of 27) of primary breast tumors exhibited aberrant methylation of TMS1. TMS1 is localized to chromosome 16p11.2-12.1 and encodes a 22-kDa predicted protein containing a COOH-terminal caspase recruitment domain, a recently described protein interaction motif found in apoptotic signaling molecules. Ectopic expression of TMS1 induced apoptosis in 293 cells and inhibited the survival of human breast cancer cells. The data suggest that methylation-mediated silencing of TMS1 confers a survival advantage by allowing cells to escape from apoptosis, supporting a new role for aberrant methylation in breast tumorigenesis.

An abnormal Ca(2+) response in mutant sarcomere protein-mediated familial hypertrophic cardiomyopathy.

Dominant-negative sarcomere protein gene mutations cause familial hypertrophic cardiomyopathy (FHC), a disease characterized by left-ventricular hypertrophy, angina, and dyspnea that can result in sudden death. We report here that a murine model of FHC bearing a cardiac myosin heavy-chain gene missense mutation (alphaMHC(403/+)), when treated with calcineurin inhibitors or a K(+)-channel agonist, developed accentuated hypertrophy, worsened histopathology, and was at risk for early death. Despite distinct pharmacologic targets, each agent augmented diastolic Ca(2+) concentrations in wild-type cardiac myocytes; alphaMHC(403/+) myocytes failed to respond. Pretreatment with a Ca(2+)-channel antagonist abrogated diastolic Ca(2+) changes in wild-type myocytes and prevented the exaggerated hypertrophic response of treated alphaMHC(403/+) mice. We conclude that FHC-causing sarcomere protein gene mutations cause abnormal Ca(2+) responses that initiate a hypertrophic response. These data define an important Ca(2+)-dependent step in the pathway by which mutant sarcomere proteins trigger myocyte growth and remodel the heart, provide definitive evidence that environment influences progression of FHC, and suggest a rational therapeutic approach to this prevalent human disease.

Perception of quantitative information for treatment decisions.

The study was designed to determine which formats for displaying quantities, such as probabilities of treatment risks and benefits, are perceived most accurately and easily by patients. Accuracy and speed of processing were compared for six different presentation formats: pie charts, vertical bars, horizontal bars, numbers, systematic ovals, and random ovals. Quantities were used in two tasks: a choice task that required larger/smaller judgments and an estimate task that required more precise evaluation. The impacts of blue-yellow color and of a treatment-decision context on performance in the two tasks were also investigated. The study included four experiments. Taken together the results suggest that the formats best for making a choice differ from those best for estimating the size of an amount. For making a choice, vertical bars, horizontal bars, numbers, and systematic ovals were equally well perceived; pie charts and random ovals caused slower and less accurate performances. For estimating, numbers led to the most accurate estimates, followed by systematic ovals. The other four formats led to the least accurate estimates. Color and context did not alter which formats were best.

Automation--down to the nuts and bolts.

Laboratories that once viewed automation as an expensive luxury are now looking to automation as a solution to increase sample throughput, to help ensure data integrity and to improve laboratory safety. The question is no longer, 'Should we automate?', but 'How should we approach automation?' A laboratory may choose from three approaches when deciding to automate: (1) contract with a third party vendor to produce a turnkey system, (2) develop and fabricate the system in-house or (3) some combination of approaches (1) and (2). The best approach for a given laboratory depends upon its available resources. The first lesson to be learned in automation is that no matter how straightforward an idea appears in the beginning, the solution will not be realized until many complex problems have been resolved. Issues dealing with sample vessel manipulation, liquid handling and system control must be addressed before a final design can be developed. This requires expertise in engineering, electronics, programming and chemistry. Therefore, the team concept of automation should be employed to help ensure success. This presentation discusses the advantages and disadvantages of the three approaches to automation. The development of an automated sample handling and control system for the STAR System focused microwave will be used to illustrate the complexities encountered in a seemingly simple project, and to highlight the importance of the team concept to automation no matter which approach is taken. The STAR System focused microwave from CEM Corporation is an open vessel digestion system with six microwave cells. This system is used to prepare samples for trace metal determination. The automated sample handling was developed around a XYZ motorized gantry system. Grippers were specially designed to perform several different functions and to provide feedback to the control software. Software was written in Visual Basic 5.0 to control the movement of the samples and the operation and monitoring of the STAR microwave. This software also provides a continuous update of the system's status to the computer screen. The system provides unattended preparation of up to 59 samples per run.

Dilated cardiomyopathy in homozygous myosin-binding protein-C mutant mice.

To elucidate the role of cardiac myosin-binding protein-C (MyBP-C) in myocardial structure and function, we have produced mice expressing altered forms of this sarcomere protein. The engineered mutations encode truncated forms of MyBP-C in which the cardiac myosin heavy chain-binding and titin-binding domain has been replaced with novel amino acid residues. Analogous heterozygous defects in humans cause hypertrophic cardiomyopathy. Mice that are homozygous for the mutated MyBP-C alleles express less than 10% of truncated protein in M-bands of otherwise normal sarcomeres. Homozygous mice bearing mutated MyBP-C alleles are viable but exhibit neonatal onset of a progressive dilated cardiomyopathy with prominent histopathology of myocyte hypertrophy, myofibrillar disarray, fibrosis, and dystrophic calcification. Echocardiography of homozygous mutant mice showed left ventricular dilation and reduced contractile function at birth; myocardial hypertrophy increased as the animals matured. Left-ventricular pressure-volume analyses in adult homozygous mutant mice demonstrated depressed systolic contractility with diastolic dysfunction. These data revise our understanding of the role that MyBP-C plays in myofibrillogenesis during cardiac development and indicate the importance of this protein for long-term sarcomere function and normal cardiac morphology. We also propose that mice bearing homozygous familial hypertrophic cardiomyopathy-causing mutations may provide useful tools for predicting the severity of disease that these mutations will cause in humans.

An alpha-cardiac myosin heavy chain gene mutation impairs contraction and relaxation function of cardiac myocytes.

Left Ventricular (LV) myocytes were isolated from 15-wk-old male mice bearing the Arg403 --> Gln alpha-cardiac myosin heavy chain missense mutation (alpha-MHC403/+), a model of familial hypertrophic cardiomyopathy. LV myocytes were classified morphologically: type I, rod shaped with parallel myofibrils; type II, irregularly shaped, shorter and wider than wild-type (WT) control cells, with parallel myofibrils; and type III, irregularly shaped with disoriented myofibrils. Compared with WT myocytes, alpha-MHC403/+ myocytes had fewer type I cells (WT = 74 +/- 3%, alpha-MHC403/+ = 41 +/- 4%, P < 0.01) and more type III cells (WT= 12 +/- 3%, alpha-MHC403/+ = 49 +/- 7%, P < 0.01). In situ histology also demonstrated marked myofibrillar disarray in the alpha-MHC403/+ hearts. With the use of video edge detection, myocytes were paced at 1 Hz (37 degrees C) to determine the effects of the mutation on myocyte function. End-diastolic length was reduced in mutant myocytes, but fractional shortening (% contraction) and sarcomere length were not. Velocity of contraction (-dL/dtmax) was depressed in mutant cells, but more in type II and III cells (-31%) than in type I cells (-18%). Velocity of relaxation (+dL/dt) was also depressed more in type II and III cells (-38%) than in type I cells (-16%). Using fura 2 dye with intracellular Ca2+ transients, we demonstrated that in alpha-MHC403/+ myocytes, the amplitude of the Ca2+ signal during contraction was unchanged but that the time required for decay of the signal to decrease 70% from its maximum was delayed significantly (WT = 159 +/- 8 ms; alpha-MHC403/+ = 217 +/- 14 ms, P < 0.01). Sarco(endo)plasmic reticulum Ca2+-ATPase mRNA levels in alpha-MHC403/+ and WT mice were similar. These data indicate that the altered cardiac dysfunction of alpha-MHC403/+ myocytes is directly due to defective myocyte function rather than to secondary changes in global cardiac function and/or loading conditions.

Celiac disease presenting as the Paterson-Brown Kelly (Plummer-Vinson) syndrome.

We describe two patients with Paterson-Brown Kelly (Plummer-Vinson) syndrome whose iron deficiency anemia was due to celiac disease. They presented with dysphagia 13 and 9 yr, respectively, before celiac disease was diagnosed. Neither had gastrointestinal symptoms suggestive of malabsorption. Celiac disease is a recognized cause of chronic iron deficiency and should be considered as an etiological factor for sideropenic dysphagia.

Induced expression of p16(INK4a) inhibits both CDK4- and CDK2-associated kinase activity by reassortment of cyclin-CDK-inhibitor complexes.

To investigate the mode of action of the p16(INK4a) tumor suppressor protein, we have established U2-OS cells in which the expression of p16(INK4a) can be regulated by addition or removal of isopropyl-beta-D-thiogalactopyranoside. As expected, induction of p16(INK4a) results in a G1 cell cycle arrest by inhibiting phosphorylation of the retinoblastoma protein (pRb) by the cyclin-dependent kinases CDK4 and CDK6. However, induction of p16(INK4a) also causes marked inhibition of CDK2 activity. In the case of cyclin E-CDK2, this is brought about by reassortment of cyclin, CDK, and CDK-inhibitor complexes, particularly those involving p27(KIP1). Size fractionation of the cellular lysates reveals that a substantial proportion of CDK4 participates in active kinase complexes of around 200 kDa. Upon induction of p16(INK4a), this complex is partly dissociated, and the majority of CDK4 is found in lower-molecular-weight fractions consistent with the formation of a binary complex with p16(INK4a). Sequestration of CDK4 by p16(INK4a) allows cyclin D1 to associate increasingly with CDK2, without affecting its interactions with the CIP/KIP inhibitors. Thus, upon the induction of p16(INK4a), p27(KIP1) appears to switch its allegiance from CDK4 to CDK2, and the accompanying reassortment of components leads to the inhibition of cyclin E-CDK2 by p27(KIP1) and p21(CIP1). Significantly, p16(INK4a) itself does not appear to form higher-order complexes, and the overwhelming majority remains either free or forms binary associations with CDK4 and CDK6.

Neonatal cardiomyopathy in mice homozygous for the Arg403Gln mutation in the alpha cardiac myosin heavy chain gene.

Heterozygous mice bearing an Arg403Gln missense mutation in the alpha cardiac myosin heavy chain gene (alpha-MHC403/+) exhibit the histopathologic features of human familial hypertrophic cardiomyopathy. Surprisingly, homozygous alpha-MHC403/403 mice die by postnatal day 8. Here we report that neonatal lethality is caused by a fulminant dilated cardiomyopathy characterized by myocyte dysfunction and loss. Heart tissues from neonatal wild-type and alpha-MHC403/403 mice demonstrate equivalent switching of MHC isoforms; alpha isoforms in each increase from 30% at birth to 70% by day 6. Cardiac dimensions and function, studied for the first time in neonatal mice by high frequency (45 MHz) echocardiography, were normal at birth. Between days 4 and 6, alpha-MHC403/403 mice developed a rapidly progressive cardiomyopathy with left ventricular dilation, wall thinning, and reduced systolic contraction. Histopathology revealed myocardial necrosis with dystrophic calcification. Electron microscopy showed normal architecture intermixed with focal myofibrillar disarray. We conclude that 45-MHz echocardiography is an excellent tool for assessing cardiac physiology in neonatal mice and that the concentration of Gln403 alpha cardiac MHC in myocytes influences both cell function and cell viability. We speculate that variable incorporation of mutant and normal MHC into sarcomeres of heterozygotes may account for focal myocyte death in familial hypertrophic cardiomyopathy.