Bedside tracer gas technique accurately predicts outcome in aspiration of spontaneous pneumothorax

BACKGROUND

There is no technique in general use that reliably predicts the outcome of manual aspiration of spontaneous pneumothorax. We have hypothesised that the absence of a pleural leak at the time of aspiration will identify a group of patients in whom immediate discharge is unlikely to be complicated by early lung re-collapse and have tested this hypothesis by using a simple bedside tracer gas technique.

METHODS

Eighty four episodes of primary spontaneous pneumothorax and 35 episodes of secondary spontaneous pneumothorax were studied prospectively. Patients breathed air containing a tracer (propellant gas from a pressurised metered dose inhaler) while the pneumothorax was aspirated percutaneously. Tracer gas in the aspirate was detected at the bedside using a portable flame ioniser and episodes were categorised as tracer gas positive (>1 part per million of tracer gas) or negative. The presence of tracer gas was taken to imply a persistent pleural leak. Failure of manual aspiration and the need for a further intervention was based on chest radiographic appearances showing either failure of the lung to re-expand or re-collapse following initial re-expansion.

RESULTS

A negative tracer gas test alone implied that manual aspiration would be successful in the treatment of 93% of episodes of primary spontaneous pneumothorax (p<0.001) and in 86% of episodes of secondary spontaneous pneumothorax (p=0.01). A positive test implied that manual aspiration would either fail to re-expand the lung or that early re-collapse would occur despite initial re-expansion in 66% of episodes of primary spontaneous pneumothorax and 71% of episodes of secondary spontaneous pneumothorax. Lung re-inflation on the chest radiograph taken immediately after aspiration was a poor predictor of successful aspiration, with lung re-collapse occurring in 34% of episodes by the following day such that a further intervention was required.

CONCLUSIONS

National guidelines currently recommend immediate discharge of patients with primary spontaneous pneumothorax based primarily on the outcome of the post-aspiration chest radiograph which we have shown to be a poor predictor of early lung re-collapse. Using a simple bedside test in combination with the post-aspiration chest radiograph, we can predict with high accuracy the success of aspiration in achieving sustained lung re-inflation, thereby identifying patients with primary spontaneous pneumothorax who can be safely and immediately discharged home and those who should be observed overnight because of a significant risk of re-collapse, with an estimated re-admission rate of 1%.

Polyethylene glycol induces apoptosis in HT-29 cells: potential mechanism for chemoprevention of colon cancer

Recent experimental evidence suggests that polyethylene glycol (PEG) is a highly effective chemopreventive agent against colon cancer; however, the mechanism(s) remain largely unexplored. To further elucidate this issue, we evaluated the effect of PEG on two human colon cancer cell lines. PEG treatment resulted in a dose- and time-dependent reduction in cell number without alteration in markers of cell proliferation. However, there was a dramatic and specific, concentration-dependent induction of apoptosis, with 50 mM PEG rendering approximately half the cells apoptotic. This corresponded with a 17-fold induction in the expression of the pro-apoptotic protein, prostate apoptosis response-4. Our data suggest that induction of apoptosis may be responsible, at least in part, for the ability of PEG to prevent experimental colon cancer.

Walking, chair rising, and stair climbing after total knee arthroplasty: patellar resurfacing versus nonresurfacing

During the past decade, the technology and design of knee joint prostheses has progressed considerably. However, there is still much controversy on whether resurfacing the patella during routine total knee arthroplasty (TKA) is necessary. This study compares the biomechanics of the lower limb in patients after TKA with and without patellar resurfacing during level walking, stair climbing, and chair rising. Eighteen patients who underwent TKA by two different surgeons using the same prosthesis were studied after full rehabilitation while walking, stair climbing, and chair rising. Patients were divided between those who were resurfaced and those who were not resurfaced. An aged-matched control population was recruited for comparison. The Hospital for Special Surgery Knee Rating Scale was used to gather clinical information. Kinematic and kinetic parameters were collected using a 5-camera Motion Analysis System and an AMTI OR6-5 force platform. For level walking, patients were asked to walk at a self-selected speed down an 8-m walkway. For stair climbing, patients were asked to climb a 4-step staircase without handrail support and for chair rising, patients were asked to rise from a chair that was positioned at the height of their knee joint line. Five trials for each side were recorded for averaging and statistical analysis. Temporal-spatial parameters and kinematic and kinetic variables at the knee joint were tested for significance using the repeated measures analysis of variance (ANOVA). There were no significant differences in the biomechanics of walking, stair climbing, or chair rising between patients after TKA with and without a resurfaced patella.

Management of spontaneous pneumothorax-a Welsh survey

The authors sought to determine to what degree current practice by hospital physicians and accident and emergency (A&E) departments in Wales conformed to the British Thoracic Society's guidelines for the management of spontaneous pneumothorax. Questionnaires were posted to all consultants involved in emergency medical admissions in Wales (149 consultant physicians and 23 A&E consultants) of whom 101 (59%) replied. Only 45% used the classification, "small, moderate, or complete" to describe the size of pneumothorax. Just 44% would do as recommended by the British Thoracic Society and discharge an asymptomatic patient with a primary pneumothorax and 34% would discharge a patient with a primary pneumothorax after successful aspiration. Only 20% were prepared to try aspiration initially for a secondary pneumothorax with a complete lung collapse. Thirty four per cent would follow the recommendation to remove a chest drain without prior clamping of the tube 24 hours after bubbling had stopped. In the event of a persistent air leak 69% would refer patients or seek a specialist opinion. Physicians with an interest in respiratory medicine tolerated persistent air leaks for significantly longer than did non-respiratory physicians (median of 7 v 5 days, p=0.001). The survey indicates that fewer than expected consultant physicians and A&E consultants in Wales manage spontaneous pneumothoraces in the way recommended by the guidelines. Physicians with an interest in respiratory medicine tended to comply with these guidelines more than general physicians with interests other than respiratory medicine or A&E consultants but the trend was not significant at the 5% level. It is felt that the guidelines should be disseminated more widely, ensuring that emergency admissions units and A&E departments have copies on display or easily accessible, and that they could be expanded to cover other aspects such as timing for surgery.

Causes and effects of road traffic accidents in Saudi Arabia

In Saudi Arabia the motor vehicle is the main means of transportation. Between 1971 and 1997; 564,762 people died or were injured in road traffic accidents, a figure equivalent to 3.5% of the total population in Saudi Arabia. During this period 66,914 people have died on the roads in Saudi Arabia due to road accidents, amounting to one person killed and four injured every hour. Over 65% of accidents occur because of vehicles travelling at excess speed and/or drivers disobeying traffic signals. Of deaths in Ministry of Health hospitals, 81% are due to road traffic accidents and 20% of their beds are occupied by traffic accidents victims. Also, 79.2% of patients admitted to Riyadh Armed Forces Hospital with spinal injuries has sustained their injuries as a result of a motor vehicle accident. We recommend compulsory use of safety seat belts in vehicles and the setting up of a new database to collect, store and analyse information relating to the road traffic accidents.

An unusual cause of depressed skull fracture: case report

BACKGROUND

Camel collision accidents are a common occurrence in Saudi Arabia, with a high rate of mortality and morbidity. Isolated injuries are rare because of the nature of impact sustained by the person.

CASE DESCRIPTION

A 4-year-old child with an isolated depressed skull fracture resulting from a camel collision is described. The other occupants of the car were crushed to death. The child sustained only an impact to his head, causing a compound depressed skull fracture with localized cortical damage.

CONCLUSIONS

Camel collision accidents are a common cause of mortality and morbidity in Saudi Arabia. Isolated skull injuries are rare and result from a localized impact. This is the first report of a compound depressed skull fracture from such an incident. The extent of the problem and efforts toward prevention are described.

Characterization of a species-specific repetitive DNA from a highly endangered wild animal, Rhinoceros unicornis, and assessment of genetic polymorphism by microsatellite associated sequence amplification (MASA)

We have cloned and sequenced a 906bp EcoRI repeat DNA fraction from Rhinoceros unicornis genome. The contig pSS(R)2 is AT rich with 340 A (37.53%), 187 C (20.64%), 173 G (19.09%) and 206 T (22.74%). The sequence contains MALT box, NF-E1, Poly-A signal, lariat consensus sequences, TATA box, translational initiation sequences and several stop codons. Translation of the contig showed seven different types of protein motifs, among which, EGF-like domain cysteine pattern signatures and Bowman-Birk serine protease inhibitor family signatures were prominent. The presence of eukaryotic transcriptional elements, protein signatures and analysis of subset sequences in the 5' region from 1 to 165nt indicating coding potential (test code value=0.97) suggest possible regulatory and/or functional role(s) of these sequences in the rhino genome. Translation of the complementary strand from 906 to 706nt and 190 to 2nt showed proteins of more than 7kDa rich in non-polar residues. This suggests that pSS(R)2 is either a part of, or adjacent to, a functional gene. The contig contains mostly non-consecutive simple repeat units from 2 to 17nt with varying frequencies, of which four base motifs were found to be predominant. Zoo-blot hybridization revealed that pSS(R)2 sequences are unique to R. unicornis genome because they do not cross-hybridize, even with the genomic DNA of South African black rhino Diceros bicornis. Southern blot analysis of R. unicornis genomic DNA with pSS(R)2 and other synthetic oligo probes revealed a high level of genetic homogeneity, which was also substantiated by microsatellite associated sequence amplification (MASA). Owing to its uniqueness, the pSS(R)2 probe has a potential application in the area of conservation biology for unequivocal identification of horn or other body tissues of R. unicornis. The evolutionary aspect of this repeat fraction in the context of comparative genome analysis is discussed.

Analysis of the evolutionarily conserved repeat motifs in the genome of the highly endangered central Indian swamp deer Cervus duvauceli branderi

We have analyzed the genome of central Indian swamp deer Cervus duvauceli branderi, an inhabitant of the Kanha National Park, a wildlife conservatory in Central India, with a view to provide a genetic basis for their extinction. Evolutionarily conserved repeat sequence motifs (GATA)3.75, TA(GATA)4, (GACA)3.75, (TGG)6 and a set of mouse beta-actin primers were used to uncover the sequence variation within and between related species by employing techniques of hybridization and AP-PCR amplification. The oligo probe carrying the GACA and TGG repeat motifs was found to be positive with Cervus genome, whereas (GATA)3.75, TA(GATA)4 and beta-actin probes did not cross-hybridize with the same. AP-PCR amplification with (GACA)3.75, unlike the (TGG)6 primer, generated distinct bands in the range of 0. 37-2.10kb amongst different genomes including Cervus. A comparative genome analysis of other species using the AP-PCR approach with (GACA)3.75 primer revealed the phylogenetic status of Cervus duvauceli branderi. From the analysis of a very limited number of Cervus DNA samples, we observed a high level of genetic homogeneity that may be a prime reason for the extinction of this species. This study has implications in the context of conservation of this endangered Cervus duvauceli branderi species.

Refined tuberculosis contact tracing in a low incidence area

Our aim was to evaluate the efficacy of a revised tuberculosis (TB) contact tracing procedure in South Glamorgan whereby routine annual radiological surveillance was abandoned and contacts were either discharged or referred to chest clinic following their initial screening. We reviewed and evaluated data from the TB contact tracing clinic, the Public Health Service Mycobacterium Reference Unit, Cardiff and the Consultant in Communicable Diseases Control, South Glamorgan Health Authority and compared these results with those of our previous study. One hundred and three index cases and 732 contacts were identified. Seven hundred and seven contacts, 526 close and 181 casual, were screened, of whom 102 casuals should not have been. One hundred and sixty-one contacts were given BCG vaccination. Fifty-four contacts were referred to the chest clinic. Seven cases of TB were detected, all in young, unvaccinated, close contacts of pulmonary disease. Twenty-one contacts were given chemoprophylaxis, 20 of whom were close contacts of pulmonary TB and one of extrapulmonary disease. Five contacts who were screened and initially discharged developed TB later: in two the protocol had not been followed and three presented with extrapulmonary TB. Compared with the results of the previous protocol fewer contacts were unnecessarily screened and referrals to the chest clinic increased, as did the number given chemoprophylaxis. The case finding rate is similar to that found prior to the revision of the protocol. The yield from tracing casual contacts continues to be nil. It is very low in contacts of extrapulmonary disease. When the protocol was followed no case of pulmonary TB was missed. The revised protocol seems to be as effective as the previous, more complex protocol. In our area, one of low incidence of TB, screening of casual contacts and of contacts of extrapulmonary TB is not cost-effective. We will concentrate even more on screening close contacts of pulmonary TB.

Camel collision as a major cause of low cervical spinal cord injury

One hundred and forty patients with low cervical spinal cord injuries, who were admitted to the Riyadh Armed Forces Hospital over the past 10 years were reviewed. Motor vehicle accidents constituted 119 (85%) of the patients. Camel collisions were a major cause of vehicle accidents 39 (33%), after rollover accidents 70 (59%), and much more than head on collisions 9 (7.5%). Male to female ratio was 14:1 with a mean age of 32 years. Camel collision although a commonly observed cause of motor vehicle accidents in the Middle East has not been mentioned in the literature before. The mechanism of injury is not much different, but the exact description of the accident and sustaining injury is interesting because it leads to localised damage to the neck without major body trauma and mortality.

Kinematic posterior cruciate ligament-retaining total knee replacements. A 10-year survivorship study of 445 arthroplasties

Survival was tested in 445 primary Kinematic knee replacements performed between January 1981 and December 1990. Three criteria were applied to indicate failure: 1) revision or recommended revision, 2) presence of moderate to severe pain or revision, and 3) lost to follow-up or revision. Using these three criteria, the survival rate at 10 years was 96%, 78%, and 69%, respectively. At last follow-up examination, 84% of knees had good or excellent Bristol knee scores with mean range of motion 100 degrees. Overall, 11 knees (2.5%) have been revised and 27 cases (6%) were graded as failures due to presence of moderate to severe pain at the time of the last evaluation. These results indicate that the posterior cruciate ligament-retaining Kinematic prosthesis provides satisfactory function and survival up to 10 years.

Phase II clinical trial of a vas deferens injectable contraceptive for the male

Following up on an earlier clinical trial demonstrating the safety of an intra-vas deferens injection of a contraceptive drug named Risug, comprised of styrene maleic anhydride (SMA) in a solvent vehicle of dimethylsulphoxide (DMSO), a study to assess the contraceptive effectiveness of a specific dose (60 mg) of SMA bilaterally was planned and implemented. Male subjects and their wives with normal reproductive profiles were the volunteer subjects. The wives were not using any contraceptives. The results reconfirm the safety and show that for a period of at least 1 year, the treatment leads to azoospermia in the male and gives pregnancy protection.

St. Georg sledge for medial compartment knee replacement. 461 arthroplasties followed for 4 (1-17) years

We evaluated the long-term outcome of 461 medial compartment knee arthroplasties operated at one orthopedic center from 1974 to 1993 through survivorship analysis. Prospective assessment was based on clinical examinations using a modified Bristol knee-scoring system and complete radiographical knee survey. 92% had good or excellent results on objective scoring, and range of motion averaged 112 degrees. 3 criteria were applied to indicate failure: 1) revision or recommended revision, 2) severe-to-moderate pain or revision, 3) lost to follow-up. 20 arthroplasties were revised or recommended to be revised at mean 5.5 years. The incidence of failure due to progression of arthrosis in the unreplaced compartment was low (< 2%). Loosening or wear occurred in 6 cases (1.5%), 2 of which developed fracture of implant. With revisions only as end-point to failure, the survival was 87% at 10 years (95% CI 81%-93%, effective number at risk = 133). In addition to revisions, 19 knees were considered to have failed, as moderate-to-severe pain was noted at follow-up and the survival was reduced to 74% at 10 years with pain or revision as endpoint (95% CI 65%-82%, effective number at risk = 105). We conclude that unicompartmental knee arthroplasty gives long-term pain relief in elderly patients with medial compartment arthrosis.

Incidence of fatal pulmonary embolism after 1,390 knee arthroplasties without routine prophylactic anticoagulation, except in high-risk cases

A consecutive series of 1,390 primary total knee arthroplasty (TKA) procedures (1,201 patients, 1,600 arthroplasties) performed between January 1980 and July 1994 were reviewed to establish the incidence of death from pulmonary embolism (PE). Nine hundred twenty-three bi- or tricompartment TKAs and 467 unicompartment TKAs were performed as one-stage procedures. Chemical thromboprophylaxis was used only in high-risk cases in which there was a history of previous thromboembolism or obesity. There were no deaths from PE after unicompartment arthroplasty procedures. Autopsy confirmed PE as the cause of death in 2 patients following bi- and tricompartment TKAs (0.22%; 95% confidence interval [CI], 0.03-0.8%). The incidence was higher for one-stage bilateral TKA as 1 of the autopsy-confirmed deaths occurred in this group 0.7% (95% CI, 0.02-3.78%). Two other deaths were certified without postmortem examination (pneumonia and myocardial infarction in each case). As PE could not be ruled out as the cause of death in the latter 2 cases, these were considered as possible PE deaths to provide the maximum possible death rate that could result. Thus, the maximum possible incidence of fatal PE after TKA without routine use of chemical anticoagulation was 0.4% (95% CI 0.1-1.1%). It is concluded that the risk of fatal PE after unilateral TKA and unicompartment knee arthroplasty is low. The risk of clinical, nonfatal thromboembolic events, which might themselves warrant prophylaxis, was not quantified in this article.

Effect of miconazole on the structure and function of plasma membrane of Candida albicans

The primary mode of action of azoles is the inhibition of cytochrome P-450 dependent 14 alpha-demethylase, a key enzyme in ergosterol biosynthesis in fungi. Our results demonstrated that Candida albicans cells grown in the presence of 10 micrograms ml-1 of miconazole (miconazole-grown), do not possess ergosterol in their plasma membranes and this ergosterol depletion leads to a drastic change in membrane fluidity as shown by fluorescence polarization measurements and unsaturation index. There was an increase in membrane order in miconazole-grown cells and a reduced rate of uptake of amino acids. We also checked for membrane permeability changes in normal mid-log phase cells (normal-grown) in short incubations (10 min) with 10 micrograms ml-1 miconazole (miconazole-incubated). Interestingly, the amino acid uptake rates except that of Gly were not affected significantly in these cells. The results suggest that in the miconazole-incubated cells, the drug is not able to alter the level of ergosterol or inhibit ergosterol biosynthesis during 10 min incubation and therefore the interaction of the drug neither leads to significant disorganization of membrane components, nor affects permease activity, whereas in the miconazole-grown cells there is ergosterol depletion leading to accumulation of biosynthetic intermediates, resulting in membrane rearrangement thereby causing a major fluidity change. This fluidity change may explain the drastic reduction of amino acid transport in miconazole-grown cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Phase I clinical trial of an injectable contraceptive for the male

Earlier studies on the rat and the monkey had demonstrated that an injection of styrene maleic anhydride (SMA) in a solvent vehicle of dimethyl sulphoxide (DMSO) into the lumen of the vas deferens is toxicologically safe and has contraceptive action. Phase I clinical trial was therefore undertaken on 38 male volunteers giving varying doses of SMA, ranging between 5 mg and 140 mg, into each vas deferens. A dose of 70 mg is the predicted therapeutic dose based on animal data. That the compound is within the vas deferens lumen during the period of the safety assessment is inferred from the effect on the spermatozoa count in ejaculates which reach azoospermic levels in the higher dose ranges. The treatment is well tolerated with only minimal side effects in a few cases and no long-term adverse effects.

Teratoid Wilms' tumour: a report of two cases

We report two cases of Wilms' tumour in which the degree of heterologous differentiation was sufficient to warrant the diagnosis of teratoid Wilms' tumour. The first description of neural elements in this Wilms' variant and the first cytogenetic analysis of teratoid Wilms' tumour are presented.

Transport of acidic amino acids in Candida albicans

In Candida albicans ATCC 10261, two kinetically different amino acid transport systems with a high (S1) and a low (S2) affinity for aspartic acid (asp) and glutamic acid (glu) were identified. The S1 for the two acidic amino acids was characterized by low Kt values while Kt values of S2 were 30 to 40 times higher. Based on competitive studies of both systems, S1 was found to be specific and common to both asp and glu while S2 was relatively less specific. The S1 and S2 systems were also different in their sensitivity to respiratory inhibitors, mercurials and a K+ channel blocker. Both systems, however, showed maximum transport rates during the mid-exponential growth phase.

Vanadate-resistant mutants of Candida albicans show alterations in phosphate uptake

Phosphate uptake studies in different strains of the dimorphic pathogenic yeast Candida albicans were undertaken to show that this yeast actively transported phosphate with an apparent Km in the range of 90-170 microM. The uptake was pH dependent and derepressible under phosphate starvation. Vanadate-resistant (van) mutants of C. albicans showed a 20-70% reduction in the rate of phosphate uptake in high phosphate medium and was associated with an increased Km and reduced Vmax. The magnitude of derepression under phosphate starvation was different between van mutants. These results demonstrate that van mutants may have developed resistance by modifying the rate of entry of vanadate.

Isolation, purification and kinetic characterization of plasma membrane H(+)-ATPase of Candida albicans

The plasma membrane ATPase of Candida albicans was solubilized by Tween 40 and purified to homogeneity on glycerol step gradient. The purified protein appeared as a single band of 100 +/- 4 KDa, represented greater than 98% of the total pure protein on densitometer scan. The purified PM-ATPase which was very specific to MgATP, had Km of about 0.77 mM and a sharp pH optimum at 6.6. Orthovanadate was able to inhibit the enzyme in a non-competitive manner, however, at higher concentrations the nature of inhibition changed to uncompetitive type. Based on molecular size, immuno cross-reactivity and sensitivity to different inhibitors, PM-ATPase of C. albicans appears to be similar to other ion pumps.

Time-controlled injectable occlusion of the vas deferens

An injectable method of obtaining vas deferens occlusion is presented. The agent used is styrene maleic anhydride (SMA) with dimethyl sulphoxide as the solvent. The special feature of the approach is that after a period of time, spermatozoa passage is spontaneously reestablished. By varying the dose of SMA administered, the interval between injection and restoration of spermatozoa flow can be regulated from as short a period as about 3 months to more than five years.

Contraception in male monkeys by intra-vas deferens injection of a pH lowering polymer

A new male method of contraception by injecting a polymer, styrene-maleic anhydride (SMA), into the lumen of the vas deferens has been studied on rhesus monkeys. The polymer has the dual feature that it can occlude the vas deferens lumen and also it can inhibit the fertilising ability of spermatozoa by virtue of the pH lowering effect. Matings with females were carried out when the lumen was completely occluded giving azoospermia as well as with partial block and spermatozoa present in the semen. All matings were infertile. Data up to one year is presented. All indications are that the contraceptive effect will last for a considerably long period.

Alterations in intestinal function in response to thyroxine and cortisone administration in undernourished rats

Imposition of undernutrition during the suckling period considerably enhanced the intestinal uptake of D-glucose and glycine compared to a control group. Brush border sucrase, and alkaline phosphatase activities were drastically reduced while lactase and leucine amino peptidase levels were significantly elevated at weaning in nutritionally deprived pups as compared to control animals. Cortisone administration to undernourished rats depressed the uptake of D-glucose but stimulated that of glycine. Thyroxine treatment to undernourished animals reduced the uptake of glucose but had no effect on glycine absorption. Brush border sucrase and alkaline phosphatase activities were stimulated in cortisone- or thyroxine-injected undernourished rats but lactase activity was depressed under these conditions. Leucine aminopeptidase activity remained unaffected in cortisone- or thyroxine-administered undernourished pups.