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Aims Total hip arthroplasty (THA) is a very successful and cost-effective operation, yet debate continues about the optimum fixation philosophy in different age groups. The concept of the 'cementless paradox' and the UK 'Getting it Right First Time' initiative encourage increased use of cemented fixation due to purported lower revision rates, especially in elderly patients, and decreased cost. Methods In a high-volume, tertiary referral centre, we identified 10,112 THAs from a prospectively collected database, including 1,699 cemented THAs, 5,782 hybrid THAs, and 2,631 cementless THAs. The endpoint was revision for any reason. Secondary analysis included examination of implant survivorship in patients aged over 70 years, over 75 years, and over 80 years at primary THA. Results Cemented fixation had the lowest implant survival in all age groups, with a total ten-year survivorship of 97.0% (95% confidence interval (CI) 95.8 to 97.8) in the cemented group, 97.6% (95% CI 96.9 to 98.1) in the hybrid group, and 97.9% (95% CI 96.9 to 98.6) in the cementless group. This was not statistically significant (p = 0.092). There was no age group where cemented fixation outperformed hybrid or cementless fixation. Conclusion While all fixation techniques performed well at long-term follow-up, cemented fixation was associated with the lowest implant survival in all age groups, including in more elderly patients. We recommend that surgeons should carefully monitor their own outcomes and use fixation techniques that they are familiar with, and deliver the best outcomes in their own hands. Cite this article: Bone Joint J 2022;104-B(2):206–211.

The objective of this experiment was to determine the effect of level of whole cottonseed (WCS) supplementation on ADG and enteric CH4 emissions of steers grazing tallgrass prairie in the summer. Steers (n = 18; initial BW = 316 ± 23 kg) were trained for 3 wk to use a portable, automated head-chamber system (GreenFeed; C-Lock Inc., Rapid City, SD). Steers were then offered from 0 to 2.9 kg/d (as fed) WCS in individual feeders for 43 d. Body weight was measured weekly before feeding. Total fat concentration of the diet (supplement + forage) at the greatest supplement intake was estimated to be 8.3% of DM. Body weight gain increased linearly as supplement intake increased (P = 0.01). Because of inadequate use of the automated head-chamber system by steers at the 0-kg WCS level, this level was excluded from further analysis. In supplemented steers, there was a tendency (P = 0.1) for a quadratic relationship between CH4 emissions (g/animal per d) and supplement intake, with minimum CH4 at 2.0 kg of supplement (WCS + bait) per day. Emission intensity (g of CH4/kg of BW gain) also responded quadratically (P

Through the process of enteric fermentation, cattle produce methane (CH), a potent greenhouse gas (GHG). Growing public concern about climate change has increased the need for accurate methods of measuring CH emissions from cattle directly to improve emission inventories and evaluate emissions mitigation techniques. The present study evaluated a ventilated head box system capable of measuring CH and carbon dioxide (CO) emissions, and oxygen (O) consumption from cattle. Six Holstein heifers were used to measure CH and CO emissions and O consumption from 2 ad libitum intake measurement periods (ADAPT and ADLIB) and 1 measurement period (RESTRICT) with intake restricted to 2% of BW on a DM basis. Methane emissions during RESTRICT were significantly lower ( < 0.0001) than both ad libitum periods. Daily CH4 emission rates per animal were 235.0 ± 6.19 L/d, 228.3 ± 6.18 L/d, and 193.2 ± 8.88 L/d for the periods ADAPT, ADLIB, and RESTRICT, respectively. Carbon dioxide emission rates were 3627 ± 90.72 L/d, 3632 ± 90.47, and 3184 ± 104.79 L/d for the ADAPT, ADLIB, and RESTRICT periods, respectively. Oxygen consumption rates were 3391 ± 99.77 L/d, 3454 ± 99.57 L/d, and 3002 ± 111.36 L/d for the periods ADAPT, ADLIB, and RESTRICT, respectively. The head box system evaluated provides an accurate method of measuring emissions from cattle and can provide information about daily variations and peaks in emissions.

Through the process of enteric fermentation, cattle produce methane (CH), a potent greenhouse gas (GHG). Growing public concern about climate change has increased the need for accurate methods of measuring CH emissions from cattle directly to improve emission inventories and evaluate emissions mitigation techniques. The present study evaluated a ventilated head box system capable of measuring CH and carbon dioxide (CO) emissions, and oxygen (O) consumption from cattle. Six Holstein heifers were used to measure CH and CO emissions and O consumption from 2 ad libitum intake measurement periods (ADAPT and ADLIB) and 1 measurement period (RESTRICT) with intake restricted to 2% of BW on a DM basis. Methane emissions during RESTRICT were significantly lower (0.0001) than both ad libitum periods. Daily CH4 emission rates per animal were 235.0 ± 6.19 L/d, 228.3 ± 6.18 L/d, and 193.2 ± 8.88 L/d for the periods ADAPT, ADLIB, and RESTRICT, respectively. Carbon dioxide emission rates were 3627 ± 90.72 L/d, 3632 ± 90.47, and 3184 ± 104.79 L/d for the ADAPT, ADLIB, and RESTRICT periods, respectively. Oxygen consumption rates were 3391 ± 99.77 L/d, 3454 ± 99.57 L/d, and 3002 ± 111.36 L/d for the periods ADAPT, ADLIB, and RESTRICT, respectively. The head box system evaluated provides an accurate method of measuring emissions from cattle and can provide information about daily variations and peaks in emissions.

Bone cement has been increasingly used in orthopaedic surgery over the last 50 years. Since Sir John Charnley pioneered the use of polymethylmethacrylate cement in total hip replacements, there have been developments in cementing techniques and an expansion in the number of orthopaedic procedures that use cement. This review covers the perioperative issues surrounding bone cement including storage, cementing techniques and complications. It also discusses specific orthopaedic applications of bone cement and future developments.

Hip fracture is a major cause of morbidity, mortality and loss of independence for the elderly. Surgical fixation of the fractured hip remains the standard of care to allow for early mobilisation and a return to independence. Operative management in this population carries its own set of problems. The altered physiological state of the older person, often coupled with significant co-morbidity, can present challenges for the anaesthetist, the surgeon and the rest of the perioperative team. This article provides an evidence-based review of the important perioperative factors associated with hip fractures in the older person and their management.

As a method of exciting shear waves in acoustic logging, the phenomenon of SH wave propagation along cylindrical double-layered elastic media surrounding a fluid-filled borehole, excited by an annular shear stress source applied to the borehole wall, is studied. The dispersion equation and excitation characteristics of guided waves and critical refracted head waves described by vertical branch cut integrals are theoretically and numerically analysed. It is found that the dispersion behaviour of guided waves as borehole radius tends to infinity is the same as that of Love waves in a half-space model with horizontally double-layered elastic media, and that the lowest-order guided waves have non-zero low cut-off frequencies. The transient full waveforms of the SH wavefield are calculated and compared with the sum of the waveforms of the component waves. Both are in good agreement.

Two lithium silicate glasses (S- and BPS-glass) were sealed to four different Ni-based superalloys (Inconel 600, Inconel 718, Haynes 230, and Hastelloy C-276) and the effects of long-term heating at 700–900°C on the chemical, microstructural, and mechanical properties of sealed interfaces were studied. The presence of a small amount of ZnO in the BPS-glass leads to the formation of a thin interfacial second phase layer and a less rough alloy interface compared to the ZnO-free S-glass. Inconel 718 was found to be the most reactive of the alloys, with Cr and Nb diffusing into the glass and forming a coarse glass-ceramic microstructure at the interface. Heat treatment of all the reaction assemblies at 900°C for 100 h in air resulted in degradation of the seals and their spontaneous failure. Heat treatments at 700 or 800°C did not cause any interfacial coarsening in BPS sealed to Inconel 600, Haynes 230, and Hastelloy C-276 alloys and did not alter the bond strength of Haynes 230 bars, sealed with a thin layer of BPS-glass, demonstrating the potential of these material combinations for applications up to 800°C.

Uncorrected diplopia is a condition that may make it unsafe for a person to operate a motor vehicle. In some jurisdictions, physicians are required by law to report the person with diplopia to the appropriate authority.In this masked study, 10 patients of varying ages with stable diplopia of greater than 6 months' duration and 10 age-matched control subjects were placed in a driving simulator and evaluated on their performance. Various cues and threats, including near-accident situations, were presented; stimulus recognition and reaction times were recorded.No significant difference was found between the groups for either cue or threat recognition responses or reaction times. Increasing age was the factor most associated with poor response performance on all test measures (P.001). Slowed response time in patients with poor binocular single vision was the only other significant association.Although response times were slower in subjects with poor binocular single vision scores, stimulus recognition responses were not significantly different; in our opinion, stimulus recognition is more relevant to driving performance and therefore chronic diplopia does not appear to be a contraindication for driving a motor vehicle.

We present two cases that support an infectious cause of inflammatory pseudotumor of the liver. Each patient had sepsis due to chronic abdominal abscesses, along with a liver mass. Both patients had exploratory celiotomy, and histologic examination of the liver mass revealed inflammatory pseudotumor of the liver. Evidence of a mixed bacterial/Actinomyces infection was noted in hepatic tissue sections in one patient, and Bacteroides caccae was cultured directly from the liver biopsy in the other patient. This is the first known report of bacteria being cultured from biopsy specimens of a hepatic pseudotumor and the only reported case of Actinomyces within a hepatic pseudotumor. Clinical and pathologic findings in these two cases indicate that an extrahepatic infectious source should be explored as a potential cause of inflammatory pseudotumor of the liver.

Respiratory disease contributes significantly to the perioperative challenges of surgery. Preexisting pulmonary co-morbidities and respiratory complications can have profound effects on patient outcomes. Knowledge of these conditions and the potentially deleterious effects of anaesthesia and surgery can enable clinicians to optimise lung function, reduce complications and improve results.

In borehole seismic experiments the presence of the borehole has a significant effect on observations. Unfortunately, including boreholes explicitly in modeling schemes excludes the use of some methods (e.g., frequency-wavenumber) and adds prohibitively to the cost of others (e.g., finite difference). To overcome this problem, the authors use the concept of an effective source/receiver array to replace the explicit representation of the borehole by a distributed seismic source/receiver. This method mimics the presence of the borehole at seismic frequencies under a wide variety of conditions without adding a significant computational cost. It includes the effects of dispersive and attenuative tube wave propagation, the generation of secondary sources at interfaces and caliper changes, and the generation of conical waves in low-velocity layers. Comparison with a finite-difference scheme with an explicit borehole representation validates the approach. The modeling method applied to a continuity logging geometry demonstrates that the presence of guided waves does not uniquely imply bed connectivity. Results for a single-well imaging geometry emphasize the dominance of the tube wave in the hydrophone synthetics and demonstrates the necessity of using clamped geophones for single-well experiments. The concept of an effective source/receiver array is an efficient way of including borehole phenomena inmore » seismic modeling methods at minimal extra computational cost.« less

Tumor necrosis factor-alpha (TNF-alpha), interleukin-1 alpha (IL-1), and interleukin-6 (IL-6) are multifunctional cytokines produced by a number of cells in response to endotoxin. We have previously demonstrated (M.-F. Tsan, J. E. White, T. A. Santana, and C. Y. Lee. J. Appl. Physiol. 68: 1211–1219, 1990, and M.-F. Tsan, C. Y. Lee, and J. E. White. J. Appl. Physiol. 71: 688–697, 1991) that tracheal insufflation of 5 micrograms of TNF-alpha or 1 microgram of IL-1 markedly protects rats against O2 toxicity and enhances pulmonary Mn superoxide dismutase (Mn SOD) activity. We now report that TNF-alpha and IL-1 at subprotective doses, e.g., 1 and 0.2 micrograms, respectively, act synergistically in protecting rats against O2 toxicity. Likewise, TNF-alpha and IL-1 at 0.005 microgram/ml each act synergistically in enhancing endothelial cell Mn SOD, but not Cu,Zn SOD mRNA levels. IL-6 at 5 or 10 micrograms provides no protective effect in rats against O2 toxicity and at up to 0.5 microgram/ml has no apparent effect on endothelial cell Mn or Cu,Zn SOD mRNA levels. However, IL-6 markedly enhances TNF-alpha- and IL-1-induced increases in Mn SOD mRNA levels and O2 tolerance. These results support an important role of Mn SOD in the protection against O2 toxicity.

objective: To assess changes in limb volume and oedema in Patients admitted to hospital for treatment of venous ulceration. Design: Prospective study in thirteen patients. Setting: Health Service teaching hospital. Patients: Thirteen patients with venous ulceration for 2 years. Interventions: Patients were admitted to hospital for bed-rest and lower limb elevation for a period of 24 hours Main outcome measures: Limb volume was measured by water displacement and impedance plethysmography. Results: During limb elevation there was a mean reduction limb volume of 524 mls (95% CI 377–671 mls) after 24 hours of bedrest. This corresponded with a reduction in impedance measured by the impedance plethysmograph of 19–0 ohms (95% CI 24.3 to 15.6 ohms). Conclusion: Measurement of the lower limb volume by water displacement and by impedance plethysmography are likely to be useful methods in the investigation of Patients with chronic venous insufficiency.

Objective:To investigate the effect of limb elevation on the microcirculation of the skin in patients with venous ulceration of the leg.Design:Prospective study in patients receiving in patient treatment for venous ulceration.Setting:Health Service teaching hospital.Patients:Thirteen patients with venous ulceration of the lower limb for more than two years were investigated.Interventions:Patients were admitted to hospital and treated by bedrest with elevation of the lower limbs by 10° above the horizontal.Main outcome measures:Laser Doppler fluximetry and transcutaneous oximetry of the skin surrounding the venous ulcers was undertaken.Results:The laser Doppler fluximetry in the periculcerous region increased by 10.8 A.U. (95% CI 17 to 4.54). However, the transcutaneous oxygen measurements did not change during the period of treatment.Conclusions:Admission to hospital with elevation of the limb for patients with venous ulceration results in ***microcirculatory changes which are probably attributable to reduction in lower limb oedema.

We studied the effect of interleukin 1 alpha (IL-1) in the protection against O2 toxicity. Tracheal insufflation of IL-1 resulted in a dose-dependent protection against O2 toxicity. All control rats died within 3 days of O2 exposure. In contrast, 84, 71, and 20% of rats insufflated with 5, 1, and 0.2 microgram(s) IL-1 (150, 30, and 6 x 10(4) U), respectively, survived 100% O2 exposure for greater than 11 days. At 2.3 days after O2 exposure, control rats showed severe pulmonary injury, which insufflation of 5 microgram(s) IL-1 markedly attenuated. The protection against O2 toxicity was associated with a selective enhancement of pulmonary Mn-superoxide dismutase (Mn-SOD) activity in IL-1-insufflated rats. In rats insufflated with IL-1 that survived exposure to 100% O2 for 7 days, the activities of pulmonary Mn-SOD, Cu,Zn-SOD, catalase, and glutathione peroxidase were all increased. The increased pulmonary Mn-SOD activity demonstrated in IL-1-insufflated rats at 2.3 days after O2 exposure may contribute to the protection against acute O2 toxicity, and the markedly increased activities of all pulmonary antioxidant enzymes shown in rats insufflated with IL-1 that survived O2 exposure for 7 days may in part be responsible for the chronic adaptation of these rats to a 100% O2 environment.

E5531, a synthetic lipid A analog, has been shown to inhibit endotoxin (lipopolysaccharide, LPS)-induced tumor necrosis factor-alpha (TNF-alpha) production by human monocytes and murine macrophages. Whether it also inhibits LPS induction of manganese superoxide dismutase (MnSOD) is not clear. In the current study, we demonstrated that E5531, while having no effect on TNF-alpha and MnSOD mRNAs by itself, markedly inhibited LPS- and lipid A-, but not TNF-alpha-, induced increases in TNF-alpha and MnSOD mRNAs in human monocytes. In contrast, E5531 at concentrations and conditions that markedly inhibit LPS-induced increases in TNF-alpha and MnSOD mRNAs, and TNF-alpha production by human monocytes, had no effect on murine peritoneal macrophages. These results demonstrate that E5531 is a potent LPS antagonist in human monocytes. However, it does not show antagonist action against LPS in murine macrophages in the range of concentrations tested, suggesting that E5531 is a more potent antagonist in humans than in mice.

Resveratrol, a natural product present in wine, has recently been shown to inhibit the growth of a number of cancer cell lines in vitro. In the current study, we have demonstrated that resveratrol inhibits the growth of THP-1 human monocytic leukaemia cells in a dose-dependent manner with a median effective dose of 12 microM. It did not induce differentiation of THP-1 cells and had no toxic effect on THP-1 cells that had been induced to differentiate into monocytes/macrophages by phorbol myristate acetate. A significant fraction of resveratrol-treated cells underwent apoptosis as judged by flow cytometric analysis of DNA content, DNA fragmentation and caspase-specific cleavage of poly(ADP-ribosyl) polymerase. Resveratrol treatment had no effect on the expression of Fas receptor or Fas ligand (FasL) in THP-1 cells, nor did it induce clustering of Fas receptors. In addition, THP-1 cells were resistant to activating anti-Fas antibody, and neutralizing anti-Fas and/or anti-FasL antibodies had no protective effect against resveratrol-induced inhibition of THP-1 cell growth. The effect of resveratrol on THP-1 cells was reversible after its removal from the culture medium. These results suggest that (1) resveratrol inhibits the growth of THP-1 cells, at least in part, by inducing apoptosis, (2) resveratrol-induced apoptosis of THP-1 cells is independent of the Fas/FasL signalling pathway and (3) resveratrol does not induce differentation of THP-1 cells and has no toxic effect on differentiated THP-1 cells. Thus, resveratrol may be a potential chemotherapeutic agent for the control of acute monocytic leukaemia.

A mutant Escherichia coli lipopolysaccharide (LPS) lacking myristoyl fatty acid markedly stimulates the activity of manganese superoxide dismutase (MnSOD) without inducing tumor necrosis factor alpha (TNFalpha) production by human monocytes (Tian et al., 1998, Am J Physiol 275:C740.), suggesting that induction of MnSOD and TNFalpha by LPS are regulated through different signal transduction pathways. The protein tyrosine kinase (PTK)/mitogen-activated protein kinase (MAPK) pathway plays an important role in the LPS-induced TNFalpha production. In the current study, we determined the effects of PTK inhibitors, genistein and herbimycin A, on the induction of MnSOD and TNFalpha in human monocytes. Genistein (10 microg/ml) and herbimycin A (1 microg/ml) markedly inhibited LPS-induced protein tyrosine phosphorylation, phosphorylation and nuclear translocation of MAPK (p42 ERK, extracellular signal-regulated kinase), and increases in the steady state level of TNFalpha mRNA as well as TNFalpha production. In contrast, at similar concentrations, genistein and herbimycin A had no effect on the LPS-induced activation of nuclear factor kappaB (NFkappaB) and induction of MnSOD (mRNA and enzyme activity) in human monocytes. In addition, inhibition of NFkappaB activation by gliotoxin and pyrrodiline dithiocarbamate, inhibited LPS induction of TNFalpha and MnSOD mRNAs. These results suggest that (1) while PTK and MAPK are essential for the production of TNFalpha, they are not necessary for the induction of MnSOD by LPS, and (2) while activation of NFkappaB alone is insufficient for the induction of TNFalpha mRNA by LPS, it is necessary for the induction of TNFalpha as well as MnSOD mRNAs.

Studies support techniques of intraoperative adjustment under general anesthesia, of eye muscle surgery, based upon the rest position (deviation) to improve surgical results. None, however, have examined the (a)symmetry, per se, of the rest position and its influence on surgical outcomes.Retrospective/prospective patient chart data and photographs taken of patients under anesthesia were judged for (a)symmetry of deviation and correlated with (a)symmetry of surgery performed on 51 exotropic patients. Two groups were compared: "matched" (symmetrical surgery for symmetrical deviations and asymmetrical surgery for asymmetrical deviations) and "opposite" in which the reverse was performed.Sensory results were "statistically significantly" better (p=0.027), the need for postoperative adjustment of adjustable sutures was "statistically significantly" less (p=0.031) and the motor results tended to be improved (p=0.237) ("clinically/medically significant") when surgery was "matched" to the deviation under anesthesia.Use of the (a)symmetry of deviations under anesthesia can improve surgical results. Therefore, the final decision as to which muscles to operate on might best be delayed until the time of surgery when that (a)symmetry can be observed. This pilot study should be confirmed by a proper completely prospective randomized study.

A double-blind trial of 0.75% metronidazole gel versus oral oxytetracycline 250 mg twice daily in the treatment of rosacea was undertaken. Over a 9-week study period, both treatments were shown to be highly effective as shown by a reduction in numbers of papules and pustules, severity of erythema and overall subjective assessment by both observer and patient. Topical metronidazole gel may be regarded as an effective alternative to oral oxytetracycline in the treatment of rosacea.

When thoracic aortic rupture is suspected, a 45-degree reverse Trendelenburg (RT) anteroposterior (AP) chest radiograph should place the mediastinal structures in a more appropriate position and allow a more accurate evaluation than a supine AP radiograph. One hundred ninety-one consecutive hemodynamically stable adult patients with major blunt thoracic trauma were initially evaluated for mediastinal abnormalities associated with aortic disruption by both supine AP chest radiograph and an AP chest radiograph with the patient in 45-degree RT position. One hundred four patients underwent contrast aortography based on mediastinal abnormalities detected on the supine AP chest radiograph. Twenty of these patients had abnormal aortograms demonstrating traumatic aortic disruption confirmed at surgery. Supine and RT chest radiographs were retrospectively compared in a blinded fashion to evaluate their specificity and positive predictive value for detection of traumatic thoracic aortic rupture. If RT chest radiographic findings had been used to determine the need for further assessment, 29 angiograms (26%) would have been eliminated, specificity would have increased from 52 per cent to 69 per cent, and positive predictive value would have increased from 19 per cent to 27 per cent. Both supine and RT chest radiographs demonstrated mediastinal widening in all 20 patients with abnormal aortograms, with no missed thoracic aortic disruptions (100% sensitivity). This study indicated that the RT chest radiograph may be used instead of the standard supine radiograph as the initial screen for mediastinal evaluation, maintaining a high sensitivity and eliminating the cost and morbidity of many unnecessary aortograms.

Following routine appointments in a paediatric dermatology clinic, the parents of 44 young children with atopic eczema and 18 with other skin conditions were interviewed regarding sleep patterns. Sleep disorders were more prevalent in the eczema children than in the control group and normal populations. "Night waking" problems were particularly common in the eczema children, whereas settling problems were not. An association was found between scratching habits and "night waking"--the more the children scratched, the greater the likelihood of their waking at night. Consideration is given to the management of the sleep problems of eczematous children.

Recombinant plasmid DNA alone or in conjunction with a gene delivery system has been used increasingly for in vivo gene transfer. However, little is known about the direct biological effects of plasmid DNA. In this study, we demonstrated that tracheal administration of a number of plasmid DNA protected rats against oxygen toxicity. This protection required the presence of intact plasmid DNA, was not due to endotoxin contamination, and was not shared by salmon testis DNA. The plasmid DNA-induced protection against oxygen toxicity was associated with the production of tumor necrosis factor (TNF) and the enhancement of pulmonary Mn-superoxide dismutase (MnSOD), CuZnSOD, and glutathione peroxidase activities. Coadministration of plasmid DNA and anti-TNF antibody (but not nonspecific IgG) partially abolished the protective effect and reduced the pulmonary MnSOD activity, suggesting that the plasmid DNA-induced oxygen tolerance was in part mediated by the endogenous TNF and MnSOD. In view of these observations and the known immunostimulatory effects of bacterial DNA, caution should be exercised in interpreting the results of in vivo gene transfer using recombinant plasmid DNA.

The use of computer-based simulations can enhance problem-based learning in nursing education. Adding interactive video allows students to "see" the patient they are interviewing and to "examine" the patient rather than having the examination findings described by the software developer. These features both increase the realism of the simulations and challenge the learner to interpret the physical examination findings. The use of interactive videotape has proved to be a medium that lends itself to in-house production of interactive video.

Herpes zoster infection is a common clinical problem in elderly people. Three of the consequences of such infection are acute rash, post-herpetic neuralgia, and, for those with trigeminal infection, ocular complications. Post-herpetic neuralgia is a severe, prolonged, debilitating complication with no known effective treatment. Acyclovir treats acute rash,*RF 1-4* but its role in preventing post-herpetic neuralgia and ocular complications remains controversial. These complications can be severe and sight threatening and can require prolonged treatment. Topical acyclovir has been shown to be beneficial when given prophylactically and in established cases.5 We examined whether high oral doses of acyclovir (800 mg five times a day for seven days) have a beneficial effect on post-herpetic neuralgia and reduce ocular involvement in the long term. Of the …

Significant progress has been made in the development of noninvasive screening techniques for evaluation of the carotid bifurcation prior to contrast angiography. The role and significance of Magnetic Resonance Angiography (MRA) as an efficient cost effective screening examination for carotid artery stenosis remains to be determined. To that end, 120 carotid vessels, in 60 consecutive patients with carotid artery disease, were studied using MRA, Duplex ultrasonography (U/S), and conventional Digital Subtraction Arteriography (DSA). In a prospective blinded manner, using a standard scoring schematic, each carotid artery was evaluated with regard to degree of stenosis, zone of stenosis, and quality of the screening examination. The efficacy of MRA and U/S for detection of extracranial carotid stenoses was correlated with conventional DSA, which was used as a "standard of reference" for each patient. Screening studies were considered positive if the vessel stenosis was determined to be greater than 40 per cent. As a screening examination, U/S yielded a sensitivity of 88 per cent and a specificity of 81 per cent with 11 false positive and 7 false negative studies. MRA yielded a sensitivity of 84 per cent and a specificity of 81 per cent with 11 false positive and 9 false negative studies. Range of cost of each imaging modality was surveyed from our region as well as ease of access to each modality. MRA and U/S achieved equivalent accuracy as screening examinations and correlated well in sensitivity and specificity when quality of the examination and experience of the examination center was taken into consideration.(ABSTRACT TRUNCATED AT 250 WORDS)

Cryptococcosis, a potentially fatal pulmonary infection, rarely occurs in advanced form in immunocompetent individuals. Radiographic findings are variable and include single and multiple mass-like infiltrates, nodules, and segmental infiltrates. MRI manifestations of pulmonary cryptococcosis have not been reported previously. We have compared MRI, CT, and plain film radiographic findings in a case of multisegmental cryptococcal pneumonia occurring as a mass simulating carcinoma in an immunocompetent individual; we have also discussed the differential radiographic evaluation of pulmonary cryptococcosis.

We have previously demonstrated that tracheal insufflation of interleukin-1 alpha (IL-1) enhances pulmonary Mn superoxide dismutase (Mn SOD) activity and protects rats against O2 toxicity (M. F. Tsan, C. Y. Lee, and J. E. White. J. Appl. Physiol. 71: 688–697, 1991). In this study, we investigated the kinetics of mRNA, specific (immunoreactive) proteins, and enzyme activities of pulmonary Mn SOD and Cu,Zn SOD in IL-1-induced O2-tolerant rats. At 1 day after IL-1 (5 micrograms) insufflation and O2 exposure, levels of Mn SOD mRNA and specific protein, but not enzyme activity, were markedly elevated. At 2.3 and 7 days after O2 exposure, levels of Mn SOD mRNA, specific protein, and enzyme activity were all increased in IL-1-treated animals. In contrast, in control rats at 2.3 days after O2 exposure, level of Mn SOD mRNA was markedly elevated, whereas levels of specific protein and enzyme activity were decreased. Levels of pulmonary Cu,Zn SOD mRNA, specific protein, and enzyme activity were unchanged in control and IL-1-treated rats, except that in IL-1-induced long-term O2-tolerant rats (7 days after O2 exposure), they were all increased. Since at 7 days after IL-1 insufflation, normoxia-exposed rats did not show increased levels of pulmonary Mn SOD or Cu,Zn SOD mRNA, the increased levels of pulmonary SOD seen in IL-1-induced long-term O2-tolerant rats are, at least in part, due to the effect of O2 exposure

We have developed a numerical technique for modeling subkilohertz seismic data acquired with a borehole hydrophone, a borehole volume source, or both, in the case of cross well data. Data acquired with such devices contain tube wave related phenomena that exist because of the borehole itself. This new technique avoids modeling the source and receiver boreholes directly, and yet models the tube wave related effects. This is done The computed line source mechanism is now used in a pre existing modeling code, overiding the normal choices of : buried point force or a buried monopole. The modeling cod1 must compute as output the wavefield at all points along the trajectory of a hypothetical receiver well.