Dynamically controlled deposition of colloidal nanoparticle suspension in evaporating drops using laser radiation.

Dynamic control of the distribution of polystyrene suspended nanoparticles in evaporating droplets is investigated using a 2.9 µm high power laser. Under laser radiation a droplet is locally heated and fluid flows are induced that overcome the capillary flow, and thus a reversal of the coffee-stain effect is observed. Suspension particles are accumulated in a localised area, one order of magnitude smaller than the original droplet size. By scanning the laser beam over the droplet, particles can be deposited in an arbitrary pattern. This finding raises the possibility for direct laser writing of suspended particles through a liquid layer. Furthermore, a highly uniform coating is possible by manipulating the laser beam diameter and exposure time. The effect is expected to be universally applicable to aqueous solutions independent of solutes (either particles or molecules) and deposited substrates.

Control of rheumatoid arthritis with conventional disease-modifying antirheumatic drugs in a tertiary hospital in central South Africa.

BACKGROUND: Rheumatoid arthritis (RA) is a highly prevalent disease with a significant impact on morbidity and life expectancy. There is a paucity of literature relating to the current state of disease control in South Africa, and none on Free State Province. OBJECTIVES: To evaluate control of RA with conventional disease-modifying antirheumatic drugs (DMARDs) in the rheumatology outpatient department of Universitas Academic Hospital, Bloemfontein, and to determine the relative impact of various factors contributing to the prevention of disease control. METHODS: A cross-sectional study was undertaken over a period of 8 months from December 2016 to August 2017 in the rheumatology outpatient department of Universitas Academic Hospital. Data were collected by means of information sheets and questionnaires completed by attending doctors. The information pertained to disease activity, possible factors contributing to poor control, and relevant demographic data. RESULTS: Information was collected from 169 patients, and data analysis was performed on 161. The results revealed that RA was controlled in 34 patients (21.1%). Of the 127 patients with uncontrolled disease, 61 (48.0%) reported dispensing issues relating to poor drug availability. Seventy-two (56.7%) of the patients with uncontrolled disease were deemed to be on insufficient treatment for their disease state, of whom 33 (45.8%) also reported concomitant dispensing issues. Other factors such as transport/access problems, administrative issues, adverse events and poor compliance/insight contributed to the inadequate control of RA to a minor extent. In terms of monthly dispensing, 159 patients (98.8%) reported receiving all their DMARDs during the first month. The vast majority of these drugs were dispensed from Universitas Hospital. This figure decreased to 119 patients (73.9%) who received all their DMARDs during the second month, mostly from district units. Only 55.3% (n=89) of the patients reported receiving all of their DMARDs from their down-referral units. CONCLUSIONS: Control of RA at this institution is suboptimal compared with national and international standards. The main contributors to poor control appear to be problems relating to dispensing of medication and inadequate escalation of therapy by doctors. Most of the concern with the dispensing of medication lies with the poor availability of DMARDs in peripheral unit pharmacies. These factors are remediable and should be attended to.

Quartz crystal microbalance detection of Vibrio cholerae O139 serotype.

A piezoelectric (PZ) quartz crystal microbalance (QCM) biosensor for the rapid detection of Vibrio cholerae serotype O139 has been developed. The antibody to this serotype was immobilized on the gold transducer surface of a 10 MHz AT cut PZ crystal. Solutions containing known antigen concentrations were then incubated for 1 h on the antibody-bound transducer. The biosensor was able to detect 10(5) cells per ml of O139 versus a background of O1 (Ogawa) serotype.

A gold foil electrode: extending the horizons for clinical electroretinography.

A gold foil ERG electrode is described. The device is inexpensive and simple to fabricate. Since it is hooked over the lower lid and makes minimal touch contact with the inferior limbal area, it can be used in circumstances which require prolonged testing of retinal function or in eyes with corneal pathology. Because the optics of the eye are not compromised, it is possible, with the use of appropriate stimuli and response-averaging techniques, to record local EFGs from relatively small retinal areas.

Pattern and Ganzfeld electroretinograms in macular disease.

The pattern electroretinogram has been found to be abnormal in all except three cases of maculopathy. This is in contrast to other electrophysiological tests, which are frequently unaffected. The degree of reduction is related to the loss of visual acuity. The response to focal flashes is less affected than the response to pattern.

Contrast sensitivity gratings in glaucoma family screening.

Contrast sensitivity was measured in the eyes of 200 consecutive patients attending the glaucoma family screening unit. One-third of the patients screened had an abnormal contrast sensitivity. Positive correlation (p less than 0.01) existed between this abnormal contrast sensitivity and cup : disc ratio, visual field loss, and age. No such correlation existed between contrast sensitivity and intraocular pressure.

A clinical, psychophysical, and electroretinographic survey of patients with autosomal dominant retinitis pigmentosa.

We have surveyed 104 patients (44 families) with autosomal dominant retinitis pigmentosa. The range of the survey includes clinical history, ocular examination, documentation of genetic history, Goldmann kinetic perimetry with IV/4 and I/4 white targets, two-colour static perimetry, and scotopic and photopic electroretinography. Comparison of interfamilial and intrafamilial patterns in the static perimetry data strongly suggests there may be at least two genetic subgroups within the disease characterised by the pattern of loss of rod function: in subgroup D (13 patients, 4 families) this is diffuse and severe, while in subgroup R (28 patients, 13 families) it is regional. In both D and R loss of cone function is regional, and in R it coincides with loss of rod function. In D patients the rod electroretinogram is absent; in all but two R cases it is present and usually substantial. All D patients were aware of night blindness before the age of 10, but most R patients not until after the age of 20. Many of the patients could not be classified because their disease was so advanced. The effect of disease duration on visual acuity and visual field area is described for all patients.

Rod and cone activity in patients with dominantly inherited retinitis pigmentosa: comparisons between psychophysical and electroretinographic measurements.

Extended electroretinographic (ERG) testing has been carried out in a series of patients with retinitis pigmentosa, dominantly inherited. In 36 of 57 cases only cone b waves were evoked. In 20 of these, psychophysical tests showed only cones mediated vision (Massof class I), while in 16 statis scotopic perimetry demonstrated residual rod function (class II). In the remaining cases, where rod ERGs were seen, the light intensities required to evoke responses were not greatly elevated. A computer model was constructed to relate psychophysical threshold measurements to ERG data. This analysis of the results suggests that in one subgroup of patients the scotopic ERG is smaller than expected from the losses of visual field and that in another the psychophysical elevation of rod visual threshold is greater than expected from ERG measurements.

A modified ERG technique and the results obtained in X-linked retinitis pigmentosa.

An electroretinographic (ERG) technique is described in which the relationship between scotopic b wave amplitude and stimulus light intensity is determined. The relative amplitude of scotopic to photopic responses is assessed by means of red light and flicker. The method is applied to the detection of ERG abnormalities in heterozygotes for X-linked retinitis pigmentosa. These have been found in only a proportion of cases. The ERG results can be used to suggest the nature of the retinal abnormality.

Disabilities and quality of life in pure and comorbid generalized anxiety disorder and major depression in a national survey.

Using a nationally representative sample, this study examines the disease-specific impairments of DSM-IV generalized anxiety disorder (GAD) by comparing them to the impairments associated with major depressive disorder (MDD). Results are based on 4181 respondents between the ages of 18-65 years who were interviewed with the 12-month version of the Munich-Composite International Diagnostic Interview as part of the German National Health Interview and Examination Survey-Mental Health Supplement (GHS). After controlling for age, gender, and other psychopathology, 'pure' current GAD without MDD (n = 33), pure MDD (n = 344) and comorbid GAD and MDD (n = 40) were each associated with high impairment as defined by poor self-perceived health, at least 3 days limited or impaired in the past month, and low quality of life scores [from the Short Form-36 Health Survey (SF-36)]. Quality of life scores on several of the SF-36 scales were significantly lower for respondents with pure GAD as compared to respondents with pure MDD. Overall, the results show that DSM-IV GAD is associated with high impairment even after controlling for other psychopathology. The impairment outcomes for GAD were comparable in size to those for MDD. These findings underline the significance of this disorder from a clinical and social perspective and provide support for the independent diagnostic status of GAD.

Malpractice and avascular necrosis: legal outcomes.

Every physician, but particularly specialists, have reason to be concerned about medical legal issues. Avascular necrosis has been established as a possible serious complication of steroid treatment in inflammatory bowel disease. Two specific Canadian cases illustrating the sequence of medical history, time, expert testimony and legal outcomes are presented. Awards plus costs in the order of $1 million or more were the result of these legal proceedings. The courts stated the major factors in finding liability against doctors were the failure to show the patient had been fully informed of treatment options. There was considerable weight given to expert testimony and the patient recollection of events to support their contentions. Adequate contemporaneous record keeping was absent to contradict evidence of the patients. The judges in both illustrative examples leaned heavily on Supreme Court of Canada guidelines whereby the patient must be informed at all stages of the medical process.

A new generation of U.S. Army flight helmets.

Head injuries are the most common cause of fatal injury in helicopter crashes. For over 80 years, the U.S. Army has used crash investigation studies to redesign flight helmets. This paper describes the evolution of the new fielded U.S. Army helmet, the Sound Protection Helmet No. 4B (SPH-4B), and compares its protective features to its predecessors, especially the SPH-4. A major contribution to the helmet design process was made by the Aviation Life Support Equipment Retrieval Program (ALSERP), a functional program at the U.S. Army Aeromedical Research Laboratory (USAARL). ALSERP has analyzed more than 500 helmets involved in crash events since 1972. Based on these studies of critical safety factors, the Army has developed and deployed the SPH-4B, a new helmet with improved energy absorption, retention, and stability.

A sensitive bladder: an atypical presentation of cancer in a U.S. Army pilot.

Bladder cancer is the most common cancer in the urinary tract, the vast majority (90%) of which are transitional cell carcinomas. A papilloma (grade I) lesion offers an excellent prognosis after excision, though recurrence is possible. The classic sign of bladder cancer is gross, painless hematuria. We report a case of transitional cell papillary carcinoma in an aircrew member with atypical presentation: irritative voiding symptoms without hematuria. With a careful history and physical, and aggressive clinical suspicion, an early diagnosis was made offering an excellent prognosis. The patient, an Army helicopter pilot, returned to flight status with a waiver.

Using simulation to evaluate clinical competence after impairment.

It is important for individual dentists and the profession to have access to a process for evaluating the clinical competence of practitioners who are professionally impaired as a result of an accident or a medical disability. No common standards for such evaluations currently exist, however, as demand for this type of assessment is still rare. This article reviews the evaluative approach taken by a team of experienced dental educators in examining three dentists who suffered from medical disabilities. An attempt was made to standardize the evaluation process by using clinical simulation to create an environment that would be comfortable for the dentists and acceptable to the lawyers and the insurance companies. Following evaluation, recommendations on individual competence were made, contributing to a faster resolution of legal and insurance issues.

Evidence that a neutral cholesteryl ester hydrolase is responsible for the extralysosomal hydrolysis of high-density lipoprotein cholesteryl ester in rat hepatoma cells (Fu5AH).

Diethylumbelliferyl phosphate (UBP) has been shown to inhibit the neutral cholesteryl ester hydrolase activity responsible for hydrolysis of cellular lipid droplet cholesteryl ester (Harrison et al., 1990). The potential for (UBP) to inhibit uptake and hydrolysis of high density lipoprotein (HDL) cholesteryl ester was studied in Fu5AH hepatoma cells, a model for HDL cholesterol delivery. Coincubation of 3H-cholesteryl ester labeled HDL with UBP resulted in a 72% decrease in the cellular free cholesterol/cholesteryl ester (FC/CE) isotope ratio, indicating an inhibition in the conversion of cholesteryl ester to free cholesterol. Total cellular 3H-CE uptake was modestly (27%) but significantly decreased by UBP. Pulse-chase experiments (15 min. pulse and 7 min. chase) were used to study the hydrolysis of HDL 3H-CE in subcellular fractions separated by percoll gradients. The conversion of 3H-CE to 3H-FC could be demonstrated in fractions that comigrated with the plasma membrane/endosome fractions but were well separated from lysosomes. Neutral cholesteryl ester hydrolase activity was detected in those same fractions. These results suggest that an extralysosomal pathway is operating in the metabolism of HDL cholesterol and its delivery to hepatoma cells.

Evidence for extralysosomal hydrolysis of high-density lipoprotein cholesteryl esters in rat hepatoma cells (Fu5AH): a model for delivery of high-density lipoprotein cholesterol.

Rat hepatoma cells (Fu5AH) were studied as a model for the net delivery of apoE-free high-density lipoprotein (HDL) cholesterol to a cell. Incubating cells with HDL results in 1) a decrease in both media-free cholesterol and cholesteryl ester concentration; 2) decreased cell sterol synthesis; and 3) increased cell cholesteryl ester synthesis. HDL cholesteryl ester uptake is increased when cells are incubated for 18 hr in cholesterol poor media. Coincubation of 3H-cholesteryl ester-labeled low-density lipoprotein (LDL) with 50 microM chloroquine or 25 microM monensin results in a decrease in the cellular free cholesterol/cholesteryl ester (FC/CE) isotope ratio, indicating an inhibition in the conversion of cholesteryl ester to free cholesterol. In contrast, chloroquine and monensin do not alter the cellular FC/CE isotope ratio for 3H-CE HDL. This evidence indicates that acidic lysosomal cholesteryl ester hydrolase does not account for the hydrolysis of HDL-CE. Free cholesterol generated from 3H-cholesteryl ester of both LDL and HDL is reesterified intracellularly. At higher HDL concentrations (above 50 micrograms/ml) HDL cholesteryl ester hydrolysis is sensitive to chloroquine. We propose that an extralysosomal pathway is operating in the metabolism of HDL cholesterol and that at higher HDL concentrations a lysosomal pathway may be functioning in addition to an extralysosomal pathway.

The evaluation and diagnosis of the dizzy patient.

In conclusion, the assessment of the dizzy patient is indeed complex and far-reaching. The expertise of family practitioners, internist, neurologists, otolaryngologists, and neurosurgeons at times is essential and one should not feel inhibited about referring the patient for further evaluation to our colleagues so that the patient may best be served and resolution of the patient's complaints may result.