Dynamics of hematopoiesis in paroxysmal nocturnal hemoglobinuria (PNH): no evidence for intrinsic growth advantage of PNH clones

PNH is characterized by expansion of one or more stem cell clones with a PIG-A mutation, which causes a severe deficiency in the expression of glycosylphosphatidylinositol (GPI)-anchored proteins. There is evidence that the expansion of PIG-A mutant clones is concomitant with negative selection against PIG-A wild-type stem cells by an aplastic marrow environment. We studied 36 patients longitudinally by serial flow cytometry, and we determined the proportion of PNH red cells and granulocytes over a period of 1-6 years. We observed expansion of the PNH blood cell population(s) (at a rate of over 5% per year) in 12 out of 36 patients; in all other patients the PNH cell population either regressed or remained stable. The dynamics of the PNH cell population could not be predicted by clinical or hematologic parameters at presentation. These data indicate that in most cases the PNH cell expansion has already run its course by the time of diagnosis. In addition, since in most cases no further expansion takes place, we can infer that the tendency to overgrow normal cells is not an intrinsic property of the PNH clone.

Provide a service ... then get paid

Receiving payment at the time of dental treatment may be a new--even foreign--concept to dentists today. But more and more practices are finding it necessary to enforce such payment policies to keep a practice viable. Sometimes, it's just a matter of establishing policies within a practice; in other cases, it pays to enlist the services of a dental financing company for patient collections.

Ozonation and alkaline-peroxide pretreatment of wheat straw for Cryptococcus curvatus fermentation

Crop residues in an Advanced Life Support System (ALS) contain many valuable components that could be recovered and used. Wheat is 60% inedible, with approximately 90% of the total sugars in the residue cellulose and hemicellulose. To release these sugars requires pretreatment followed by enzymatic hydrolysis. Cryptococcus curvatus, an oleaginous yeast, uses the sugars in cellulose and hemicellulose for growth and production of storage triglycerides. In this investigation, alkaline-peroxide and ozonation pretreatment methods were compared for their efficiency to release glucose and xylose to be used in the cultivation of C. curvatus. Leaching the biomass with water at 65 degrees C for 4 h prior to pretreatment facilitated saccharification. Alkaline-peroxide and ozone pretreatment were almost 100% and 80% saccharification efficient, respectively. The sugars derived from the hydrolysis of alkaline-peroxide-treated wheat straw supported the growth of C. curvatus and the production of edible single-cell oil.

Short-Term 17-β-Estradiol Administration Does Not Affect Metabolism in Young Males

We have previously demonstrated that females oxidize more lipid and less protein and carbohydrate during endurance exercise [21]. Several studies in male rats have demonstrated similar metabolic changes after 4 d of 17-beta-estradiol (E2) administration. Our purpose was to study the effects of E2 administration upon substrate metabolism during 90min of cycle ergometry at 60% VO2peak in 11 healthy, young males. E2 was administered in a single-blind, cross-over, randomized fashion for 11 d (100 microg.d(-1) x 3.5d --> 200 microg.d(-1) x 3.5 d --> 300 microg.d(-1) x 4.0 d). Respiratory exchange ratio (RER), VO2, Ve, HR, lactate, and glucose were measured every 30 min during exercise and E2, testosterone TEST, glycerol and triglycerides were measured prior to exercise T = 0 min. Muscle biopsies were taken from the vastus lateralis before and after exercise for glycogen determination. Estradiol treatment resulted in lower plasma TEST (20.8-->7.8 nmol.L(-1), P<0.0001) and higher plasma E2 (168.1 327.3 pmol.L(-1), P < 0.002). Therewere no effects of E2 treatment upon any of the other measured variables including muscle glycogen: (E2 - PRE = 529.3 --> POST = 237.9; PL-PRE = 582.2 --> POST = 262.4 mmol.kg(-1) [dm]). We concluded that short-term E2 treatment increased plasma E2 to female follicular levels in males but had no effect upon lipid or carbohydrate metabolism.

Writing your curriculum vitae

Your curriculum vitae (CV) is your gateway to shortlisting. A good CV takes a long time to prepare. It should not only record your training but, more importantly, should reflect your 'physicianly' qualities, management skills and knowledge of health-care systems.

Swallowing in myotonic muscular dystrophy: a videofluoroscopic study

OBJECTIVES

(1) To determine how swallow function in patients with myotonic muscular dystrophy (MD) differs from that of healthy controls, (2) to identify the contributors to and predictors of improvement, and (3) to evaluate strategies that facilitate swallowing.

DESIGN

Observational.

SETTING

University medical center.

PARTICIPANTS

Eighteen adults with myotonic MD (age range, 24-58 yr) and 60 healthy adult control subjects (age range, 18-73 yr).

INTERVENTIONS

Swallow facilitation strategies.

MAIN OUTCOME MEASURES

Between-group comparisons of mean bolus transit times, onsets of swallow gestures, and displacement measures obtained by dynamic lateral view videofluoroscopy.

RESULTS

The MD patients' bolus transit times were significantly longer, and onsets of some swallow gestures were significantly delayed. Upper esophageal sphincter opening was prolonged (myotonic MD,.61 +/-.13s; control,.5 +/-.11s). Hyoid displacement was significantly less in men with myotonic MD (1.9 +/-.05 cm) than in male controls (2.4 +/-.68 cm); this difference was not observed between control and myotonic women. Of particular importance was the markedly reduced pharyngeal constriction found in the MD group.

CONCLUSIONS

Weakness associated with the disease, as opposed to myotonia, was the most significant contributor to impairment. Persons at risk for aspiration may be identified by a measure of pharyngeal area. Selected strategies to facilitate pharyngeal clearing are worthwhile.

Short-term 17beta-estradiol decreases glucose R(a) but not whole body metabolism during endurance exercise

The female sex hormone 17beta-estradiol (E(2)) has been shown to increase lipid and decrease carbohydrate utilization in animals. We administrated oral E(2) and placebo (randomized, double blind, crossover) to eight human male subjects for 8 days ( approximately 3 mg/day) and measured respiratory variables, plasma substrates, hormones (E(2), testosterone, leptin, cortisol, insulin, and catecholamines), and substrate utilization during 90 min of endurance exercise. [6,6-(2)H]glucose and [1,1,2,3,3-(2)H]glycerol tracers were used to calculate substrate flux. E(2) administration increased serum E(2) (0.22 to 2.44 nmol/l, P < 0.05) and decreased serum testosterone (19.4 to 11.5 nmol/l, P < 0.05) concentrations, yet there were no treatment effects on any of the other hormones. Glucose rates of appearance (R(a)) and disappearance (R(d)) were lower, and glycerol R(a)-to-R(d) ratio was not affected by E(2) administration. O(2) uptake, CO(2) production, and respiratory exchange ratio were not affected by E(2); however, there was a decrease in heart rate (P < 0.05). Plasma lactate and glycerol were unaffected by E(2); however, glucose was significantly higher (P < 0. 05) during exercise after E(2) administration. We concluded that short-term oral E(2) administration decreased glucose R(a) and R(d), maintained plasma glucose homeostasis, but had no effect on substrate oxidation during exercise in men.

European Epidemiologic Registry of Cystic Fibrosis (ERCF): comparison of major disease manifestations between patients with different classes of mutations

SUMMARY. By August 1997, 11,749 patients with cystic fibrosis had been enrolled in the European Epidemiologic Registry of Cystic Fibrosis (ERCF). Genotype analysis had been performed on 8,963 (76%) of these patients, and the majority had one or two identifiable mutations. Patients with known mutations were classified according to the type of mutation (Classes I-V), and were grouped according to the class of mutation on both chromosomes. This resulted in six subgroups, including all patients homozygous for Class I (I/I, n = 72), for Class II (II/II, n = 5,020), and for Class III mutations, (III/III, n = 23). Since there were only 23 patients homozygous for Class III mutations, a fourth group was made up of patients who were compound heterozygous for a Class II and III mutation (II/III, n = 265). There were only five patients homozygous for Class IV mutations, and consequently a fifth group was made up of all patients carrying at least one Class IV mutation, regardless of the nature of the mutation on the other chromosome (IV/any, n = 187). None were homozygous for Class V mutations; consequently, a sixth group consisted of patients carrying at least one Class V mutation (V/any, n = 22). Mean age was highest in groups III/III, IV/any, and V/any (15.6, 16, and 17 years, respectively) as opposed to 12.4 years in group II/II and 13.4 in group II/III, but both group III/III and V/any were small, and the confidence interval of the mean was large. The percentage of patients receiving pancreatic enzymes was lower in groups IV/any and V/any than in any of the other groups, i.e., approximately 50% of patients 18 years or older in both groups as opposed to between 90-100% of all other patients regardless of age. The prevalence of diabetes mellitus increased with age from 2.6% in patients < 18 years to 22.1% in patients 18 years or older in the large group II/II, but was only 1.5% in patients 18 years or older in group IV/any. Disregarding the small group III/III, abnormally elevated liver enzymes and/or bilirubin (1.5 x upper normal limit) was much less frequent in group IV/any than in any of the other groups, both overall and in patients aged 18 years or more. The course of lung disease appeared to be less dependent on genotype than pancreatic function, with only minor differences between groups; however, the mean values of both FVC % and FEV(1) % were slightly higher in group IV/any than all other groups in both younger and older patients. The same was found for the prevalence of some major clinical signs of severe lung disease, such as clubbing, hyperinflation, and crepitations. Overall mean weight expressed as an age percentile was markedly higher in group IV/any than in any other group, which may be related to the finding of a much lower prevalence of chronic P. aeruginosa infection in patients 18 years or older belonging to group IV/any (and V/any) than in any other group. In conclusion, the presence of a class IV mutation appears to offer some degree of protection against pancreatic insufficiency, diabetes mellitus, and liver disease. We confirmed that lung disease follows a milder clinical course in patients with a class IV mutation and that the presence of a class IV mutation (and possibly class V) is associated with a delay in the onset of P. aeruginosa infection.

Client’s experiences of their shoulder pain and disability

The purpose of this qualitative study was to enhance understanding of what it is like to suffer from chronic shoulder pain from the perspectives of those living with the experience.Unstructured interviews, using the open-ended question “tell us about your shoulder", were used to allow the twelve clients to elaborate freely on their feelings and experiences. Interviews were recorded and transcribed verbatim. These transcriptions were coded and categorized. Five themes emerged from the categories: Pain, Activities, Emotional Responses, Relationships and Coping Mechanisms. These findings expand understanding about quality of life for clients living with chronic shoulder pain and disability.

Simple two-color array-based approach for mutation detection

The ability to analyze multiple polymorphic/mutation sites rapidly and accurately is pivotal in all areas of genetic analysis. We have applied single nucleotide primer extension (SNE) for detection of multiple point mutations in a micro-array format using two-color, fluorescent dye-tagged dideoxynucleoside triphosphate terminators (ddNTPs). The oligonucleotide primer ending one nucleotide short of the mutation site being probed is bound to the slide and single-base extended in place with two different Cy5/Cy3 dye-tagged terminators using solution-phase, locus-specific, single-stranded complementary templates generated by PCR from genomic DNA. The composite fluorescence produced contains peaks of distinct wave lengths corresponding to each Cy dye-tagged terminator incorporated, resulting in a fluorescent 'fingerprint' for each DNA target. DNA polymerase-catalyzed incorporation of Cy dye-tagged dideoxynucleoside triphosphates was dependent on the particular dyes, the specific ddNTP, the DNA target concentration, sequence of the template, on-slide temperature cycling and washing conditions. Results from analysis of mutations in the human hemochromatosis and connexin 26 genes show that this approach has several advantages over existing methods and is simple, rapid, robust, cost effective and accurate with potential applications in many areas of genetic analysis.

An examination of the role of clinical psychology in meeting the needs of young disabled clients and their families/carers

This paper examines the views of clients with a physical disability, general practitioners and staff working in health and social work physical disability services about the needs of young disabled people. The most common area of disability seen by GPs was respiratory, followed by cardiac problems and stroke. With the exception of cardiac patients a third to over half of GPs felt that the needs of the identified groups were not being adequately met, in particular the needs of individuals with progressive neuromuscular problems. Over a quarter of clients felt that their needs were not being adequately met. Ninety-five percent of GPs and 100% of staff identified psychological needs of clients. For clients themselves, physical needs are ranked highest, with over 33 percent identifying psychological problems, 50 percent neuropsychological problems and 25 percent psychosexual difficulties as priority needs. In relation to carers, over 90 percent of GPs, 100% of staff and 50 percent of clients highlighted psychological needs. The majority of participants felt that clinical psychology had an important role to play in physical disability services. There was broad agreement on the areas of need which psychology would be seen to address. These were psychological needs, behavioural problems, neuropsychological problems and relationship/psychosexual difficulties. A high percentage of both staff and GPs also saw a role for clinical psychology in meeting the psychological, relationship and psychosexual needs of carers.

Structural displacements in normal swallowing: a videofluoroscopic study

Dynamic videofluoroscopic swallow studies were performed on 60 normal adult volunteers to establish normative data for displacement of upper aerodigestive tract structures during deglutition. Variables evaluated included hyoid bone displacement, larynx-to-hyoid bone approximation, pharyngeal constriction, and the extent of pharyngoesophageal sphincter (PES) opening during liquid swallows of 1, 3, and 20 cc. Results showed direct relationships between bolus size and hyoid displacement, between bolus size and PES opening, and between bolus size and pharyngeal constriction. Only hyoid-to-larynx approximation remained unchanged across bolus sizes. Sex differences were noted for all variables except PES opening. Reliability for most measurement variables was excellent. To our knowledge, normative data for pharyngeal constriction and larynx-to-hyoid approximation have not previously been described.