A novel method for chronic measurement of respiratory function in the conscious monkey

INTRODUCTION

Chronic measurement of respiratory function in the conscious monkey has been limited by the ability to monitor pleural pressure. Previous attempts to measure pleural pressure chronically in conscious animals have involved surgical implantation of pressure-sensitive catheters directly into the pleural cavity. The success of these techniques has been limited by lung damage and/or tissue growth and encapsulation of the pressure-sensitive catheter with damping or loss of the signal. These problems have been eliminated by developing a novel surgical procedure for placement of a pressure-sensitive catheter beneath the pleural surface.

METHODS

A pressure-sensitive catheter (attached to a radiotelemetry transmitter) was surgically implanted beneath the serosal layer of the esophagus within the thoracic cavity. This was accomplished by performing a midline laparotomy, making a small incision in the serosal layer of the esophagus caudal to the diaphragm, and advancing the catheter cranially along the esophagus and beneath the serosal layer into the thoracic cavity. The catheter was secured to the esophageal wall and the telemetry transmitter was sutured to the inner abdominal wall. Respiratory airflow measurements were obtained using a restraint chair equipped with a clear plastic helmet (plethysmograph chamber) that seals around the neck and encloses the head.

RESULTS

The decreases in pleural pressure during inspiration ranged from -5 to -15 mmHg and remained constant for at least 36 weeks following surgery. Intravenous administration of the respiratory depressant morphine, exposure to the respiratory stimulant 8% CO2, and intravenous administration of the bronchoconstrictive agent methacholine verified that this technique was able to detect and quantify ventilatory changes and an increase in airway resistance.

DISCUSSION

This novel method for chronic measurement of pleural pressure will facilitate evaluation of the effects of drugs, environmental agents, or disease on respiratory function by allowing repeated measurements of both ventilatory (breathing) patterns and the mechanical properties of the lung in a conscious nonhuman primate.

Arthroscopic laser extirpation of metacarpophalangeal synovial pad proliferation in eleven horses

A new surgical technique for treatment of chronic metacarpophalangeal synovial pad proliferation in the horse and the findings and long-term follow-up from 11 clinical cases are described. The medical records of all equine lameness cases attributed to metacarpophalangeal synovial pad proliferation admitted to the College of Veterinary Medicine at Cornell University (1991-1996) were reviewed and all those treated surgically by laser extirpation were included in this study. Retrieved data included subject details, preoperative lameness, ultrasonography, radiography and synovial fluid evaluations and lesion histopathology. Lesions were ablated using a CO2 or a Nd:YAG laser intra-articularly with arthroscopic guidance. Long-term follow-up was provided by telephone conversation with owners or trainers. All horses had fetlock joint effusion and were lame at presentation. Mean synovial pad thickness measured ultrasonographically was 9.0 mm (range 6-15 mm). Seven horses (64%) had radiographic evidence of remodelling of the dorsal cortex of distal McIII and 3 horses (27%) had concurrent dorsal proximal P1 fractures. No postoperative complications were noted. All 11 horses returned to training within 90 days of surgery without recurrence of the lesion(s). Laser extirpation of metacarpophalangeal synovial pad proliferation using arthroscopic guidance provided a rapid, safe and efficient method for surgical removal of such lesions without complications or recurrence. This surgical technique provides a suitable alternative to more conventional treatments for chronic metacarpophalangeal synovial pad proliferation in horses, particularly for removal of very large, fibrotic masses.

Hypoplastic Left Heart Syndrome

Hypoplastic left heart syndrome (HLHS) is a complex combination of cardiac malformations that probably results from multiple developmental errors in the early stages of cardiogenesis and that, if left untreated, invariably proves fatal. A variety of chest radiographic findings are seen in patients with HLHS, including an enlarged cardiac silhouette (notably a prominent right atrium), pulmonary venous hypertension, an atrial septal defect, and valvular stenosis or atresia. The recent evolution of palliative surgical procedures (modified Norwood procedure, bidirectional cavopulmonary shunt, modified Fontan procedure, aortic valvuloplasty, heart transplantation) has increased the survival rate in children with HLHS. Echocardiography allows accurate assessment of the size and location of the ductus arteriosus, the hemodynamics of the aortic root, the patency and size of the foramen ovale or atrial septal defect, and the presence of a ventricular septal defect to help determine whether surgical intervention is appropriate and, if so, to facilitate planning. Pediatric radiologists now view radiologic images obtained in patients with HLHS before surgical intervention and at important intervals during treatment. Familiarity with the malformations that characterize HLHS and the surgical procedures used to enhance postnatal survival will help pediatric radiologists provide better care for patients with this relatively common pathologic condition.

Application of a very high-throughput digital imaging screen to evolve the enzyme galactose oxidase

Directed evolution has become an important enabling technology for the development of new enzymes in the chemical and pharmaceutical industries. Some of the most interesting substrates for these enzymes, such as polymers, have poor solubility or form highly viscous solutions and are therefore refractory to traditional high-throughput screens used in directed evolution. We combined digital imaging spectroscopy and a new solid-phase screening method to screen enzyme variants on problematic substrates highly efficiently and show here that the specific activity of the enzyme galactose oxidase can be improved using this technology. One of the variants we isolated, containing the mutation C383S, showed a 16-fold increase in activity, due in part to a 3-fold improvement in K(m). The present methodology should be applicable to the evolution of numerous other enzymes, including polysaccharide-modifying enzymes that could be used for the large-scale synthesis of modified polymers with novel chemical properties.

Continuous wave Doppler cardiac output: use in pediatric patients receiving inotropic support

Doppler estimates of cardiac output have been shown to correlate closely with invasive measurement of cardiac output in hemodynamically stable adults and children. However, this method has not been validated in hemodynamically unstable pediatric patients. To assess the accuracy of continuous wave Doppler echocardiography in pediatric patients with unstable hemodynamics, we performed 27 simultaneous Doppler and thermodilution comparisons in 12 pediatric patients receiving inotropic support and afterload-reducing agents. Doppler cardiac output was calculated using aortic diameter measured from long-axis two-dimensional echocardiograms at three different sites: the aortic valve anulus, the aortic root at the sinuses of Valsalva, and the ascending aorta. For all measurements, there was a close correlation between Doppler and thermodilution techniques. However the site of measurement of aortic diameter had a significant impact on the strength on the correlation and the variability between Doppler and thermodilution. The best correlation and least variability were obtained using the aortic valve anulus diameter (r = 0.94). On serial determinations, percent change in Doppler stroke volume correlated well with thermodilution stroke volume (r = 0.87) and was useful in detecting both direction and magnitude of change in thermodilution stroke volume. Despite the administration of positive inotropic and afterload-reducing agents, Doppler cardiac output is a useful method for estimating cardiac output in hemodynamically unstable pediatric patients.

New insights into the mechanisms of lipid-body biogenesis in plants and other organisms

A comparative approach has been used to study the role of several lipid-body-binding proteins in plants and animals. Caleosins are a newly discovered class of calcium-binding lipid-body proteins found in plants and fungi, which we now report to have separate endoplasmic reticulum- and lipid-body-associated isoforms. We also compare the lipid-body targeting of oleosin from plants and the core protein of the hepatitis C virus when they were expressed separately in lipid-accumulating animal cell lines. This is a novel and powerful approach to investigating the factors that determine the lipid-body targeting of a wide range of proteins.

Differential expression of diacylglycerol acyltransferase (DGAT) genes in olive tissues

Fatty acids are accumulated in triacylglycerols (TAGs), in specialized organelles of seeds named oil bodies. The major site of TAG accumulation is detected in developing seed and mesocarp of certain species. We have isolated two cDNAs encoding DGAT enzymes from olives. The deduced polypeptides differ by 26 amino acids in size. However, they have high homology and almost identical hydropathy profiles. The DGAT gene is expressed in all tissues that synthesize TAGs. However, higher levels of DGAT transcripts have been detected in seed tissues of developing olive drupe. DGAT expression and mRNA accumulation in drupe tissues is developmentally regulated. Each DGAT transcript shows a distinct profile of accumulation. The existence of two different DGAT transcripts might reflect two different enzymes with discrete function and/or localization.

The effects of methylprednisolone on normal and monocyte-conditioned medium-treated articular cartilage from dogs and horses

OBJECTIVE

To study in vitro (1) the dose-response relationships between proteoglycan metabolism in normal and corticosteroid-treated articular cartilage; (2) long-term proteoglycan metabolism after treatment of articular cartilage with corticosteroids; and (3) the effect of corticosteroids on proteoglycan metabolism in articular cartilage treated with monocyte-conditioned medium (MCM).

STUDY DESIGN

Equine and canine articular cartilage explants were treated with corticosteroids and MCM. Proteoglycan synthesis and degradation were measured by radioactive labeling in short-term culture, and the long-term effect of corticosteroid treatment on proteoglycan metabolism was studied in normal explants.

ANIMALS

Two young cross-breed horses and 3 young Labrador retrievers.

METHODS

Equine articular cartilage explants were incubated in medium containing methylprednisolone sodium succinate (MPS) at 0, .001, .01, .1, 1, and 10 mg/mL (final concentration) for 1 day and then in fresh medium without MPS. Proteoglycan synthesis was measured by incorporation of sodium [35S]sulfate at 1, 3, 7, 10, and 13 days after initial treatment with MPS. Proteoglycan release was measured from separate explants prelabeled with sodium [35S]sulfate and treated similarly. Equine articular cartilage explants were treated with equine MCM simultaneously with, and 24 hours before MPS, at 0, 0.01, 0.1, 1, or 5 mg/mL for 72 hours. Proteoglycan synthesis and degradation in these explants was compared. Proteoglycan synthesis and degradation were measured similarly in canine articular cartilage explants treated simultaneously with canine MCM and MPS at 0, 0.001, 0.01, 0.1, 1 and 10 mg/mL for 72 hours. Equine articular cartilage explants treated with 0, 0.01, 0.1, 1, and 5 mg/mL of MPS for 72 hours were evaluated histologically.

RESULTS

Proteoglycan synthesis in normal equine articular cartilage was severely depressed by 10 mg/mL MPS for 24 hours, and proteoglycan synthesis failed to recover after 13 days of culture in medium without MPS. Cartilage treated with 5 mg/mL MPS had pyknotic chondrocyte nuclei and empty lacunae. Concentrations of 1 and 0.1 mg/mL MPS depressed proteoglycan synthesis in normal equine cartilage explants. For these 2 concentrations, proteoglycan synthesis recovered 2 days after MPS removal and increased significantly (P < .05) 7 days after treatment with MPS compared with controls without MPS. Concentrations of 0.001 and 0.01 mg/mL MPS did not significantly affect proteoglycan synthesis in normal equine cartilage explants. Cumulative proteoglycan loss over 13 days in culture from normal equine explants treated for 24 hours with different concentrations of MPS was not significantly different between treatment groups at any time point. MCM significantly depressed proteoglycan synthesis in both canine and equine articular cartilage explants and significantly increased proteoglycan release. These effects were prevented in the canine explants by simultaneous treatment with MPS at 1 and 0.1 mg/mL, and proteoglycan release induced by MCM in equine articular cartilage was inhibited by 1 mg/mL MPS.

CONCLUSIONS

Concentrations of 1.0 and 0.1 mg/mL MPS alleviated articular cartilage degradation in MCM-treated articular cartilage in vitro. These concentrations of MPS in contact with normal cartilage explants for 24 hours are unlikely to be detrimental in the long term to proteoglycan synthesis. The response of articular cartilage to MPS was affected by treatment with MCM so that results of experiments with normal articular cartilage explants may not reflect results obtained with abnormal cartilage.

CLINICAL RELEVANCE

It may be possible to find an intraarticular concentration of corticosteroid that protects articular cartilage against cytokine-induced matrix degradation yet not have prolonged or permanent detrimental effects on chondrocyte matrix synthesis.

Caleosins: Ca2+-binding proteins associated with lipid bodies

We have previously identified a rice gene encoding a 27 kDa protein with a single Ca2+-binding EF-hand and a putative membrane anchor. We report here similar genes termed caleosins, CLO, in other plants and fungi; they comprise a multigene family of at least five members in Arabidopsis (AtClo1-5). Northern hybridization demonstrated that AtClo2-4 mRNAs levels were low in various tissues, while AtClo1 mRNA levels were high in developing embryos and mature seeds. Analysis of transgenic Arabidopsis plants expressing the GUS reporter under control of the AtClo1 promoter showed strong levels of expression in developing embryos and also in root tip cells. Antibodies raised against AtCLO1 were used to detect caleosin in cellular fractions of Arabidopsis and rapeseed. This indicated that caleosins are a novel class of lipid body proteins, which may also be associated with an ER subdomain.

Implementation of a continuous, enzyme-coupled fluorescence assay for high-throughput analysis of glutamate-producing enzymes

Enzymatic formation of glutamate is critical to numerous biological pathways. However, current methods for assaying the activities of glutamate-forming enzymes are not particularly suitable for high-throughput screening in drug discovery. We present a continuous-read, fluorometric assay for high-throughput analysis of glutaminases. This assay is adapted to a microplate format and employs glutamate oxidase and horseradish peroxidase to couple glutamate formation to production of the fluorescent reporter molecule, resorufin, for enhancement of sensitivity (M. Zhou, Z. Diwu, N. Panchuk-Voloshina, and R. P. Haughland, 1997, Anal. Biochem. 253, 162-168). Described herein is the selection of suitable levels of coupling enzymes for optimal kinetic response and lag time of the reporter system, based on the kinetic characteristics of the individual coupling enzymes. Finally, implementation of the assay in a format for high-throughput kinetic analysis of glutaminases is demonstrated for Escherichia coli carbamoyl phosphate synthase. Derived kinetic constants are comparable to literature values determined using a variety of assay techniques.

Mortality and morbidity associated with early-onset preeclampsia

OBJECTIVE

To examine the management of early-onset preeclampsia and its maternal and fetal morbidity and mortality.

DESIGN

Retrospective cohort study of 49,812 births at a university teaching hospital between June 1986 and March 1997. Seventy-one women were identified with a diagnosis of preeclampsia with an onset at less than 30 completed weeks of gestation.

RESULTS

The incidence of very preterm preeclampsia was 1 in 682 total births. The mean diagnosis to delivery interval (range) was 14 days (0-49 days). There were no maternal deaths. Fifteen women (21%) had developed HELLP/ELLP syndrome, 9 (13%) had renal failure, 1 (1.4%) had eclampsia, and 11 (15%) had an abruption. Five women (7%) had a termination of pregnancy, 57 (80%) were delivered by cesarean section, and 4 (5%) required a classical incision. There were 12 intrauterine deaths (16%), 9 neonatal deaths (12%), and 52 neonatal survivors (72%). Two of the survivors were known to have neurological impairment at the 2-year follow-up.

CONCLUSIONS

A conservative approach to the management of early-onset preeclampsia results in a good obstetric outcome for the majority of fetuses, but this must be balanced against the significant risk of morbidity to the mothers.

Selective inhibition of bacterial dihydroorotate dehydrogenases by thiadiazolidinediones

Dihydroorotate dehydrogenase is a critical enzyme of de novo pyrimidine biosynthesis in prokaryotic and eukaryotic cells. Differences in the primary structure of the enzymes from Gram-positive and -negative bacteria and from mammals indicate significant structural divergence among these enzymes. We have identified a class of small molecules, the thiadiazolidinediones, that inhibit prototypical enzymes from Gram-positive and -negative bacteria, but are inactive against the human enzyme. The most potent compound in our collection functioned as a time-dependent irreversible inactivator of the bacterial enzymes with k(inact)/K(i) values of 48 and 500 M(-1) sec(-1) for the enzymes from Escherichia coli and Enterococcus faecalis, respectively. The data presented here indicate that it is possible to inhibit prokaryotic dihydroorotate dehydrogenases selectively while sparing the mammalian enzyme. Thus, this enzyme may represent a valuable target for the development of novel antibiotic compounds.

Long-term outcome in congenitally corrected transposition of the great arteries: a multi-institutional study

OBJECTIVES

The purpose of this study was to determine long-term outcome in adults with congenitally corrected transposition of the great arteries (CCTGA), with particular emphasis on systemic ventricular dysfunction and congestive heart failure (CHF).

BACKGROUND

Patients with CCTGA have the anatomical right ventricle as their systemic pumping chamber, with ventricular dysfunction and CHF being relatively common in older adults.

METHODS

Retrospective analysis of records of 182 patients from 19 institutions were reviewed to determine current status and possible risk factors for systemic ventricular dysfunction and CHF. Factors considered included age, gender, associated cardiac defects, operative history, heart block, arrhythmias and tricuspid (i.e., systemic atrioventricular) regurgitation (TR).

RESULTS

Both CHF and systemic ventricular dysfunction were common in groups with or without associated cardiac lesions. By age 45, 67% of patients with associated lesions had CHF, and 25% of patients without associated lesions had this complication. The rates of systemic ventricular dysfunction and CHF were higher with increasing age, the presence of significant associated cardiac lesions, history of arrhythmia, pacemaker implantation, prior surgery of any type, and particularly with tricuspid valvuloplasty or replacement. Aortic regurgitation (a previously unreported problem) was also relatively common in this patient population.

CONCLUSIONS

Patients with CCTGA are increasingly subject to CHF with advancing age; this complication is extremely common by the fourth and fifth decades. Tricuspid (systemic atrioventricular) valvular regurgitation is strongly associated with RV (anatomical right ventricle connected to aorta in CCTGA patients; systemic ventricle in CCTGA) dysfunction and CHF; whether it is causative or a secondary complication remains speculative.

Results of the double switch operation in the current era

BACKGROUND

In patients with atrioventricular and arterioventricular discordance congenitally corrected transposition, the morphologically right ventricle may progressively deteriorate while functioning in the systemic circuit. The double switch operation has been proposed to limit this functional deterioration.

METHODS

From October 1993 to August 1998, the records of 27 patients with congenitally corrected transposition were reviewed. Age at operation ranged from 3 months to 55 years. Associated defects included ventricular septal defects in 18, pulmonary atresia in 7, and pulmonary stenosis in 11 patients. Twenty-two patients had double switch operations (10 arterial switch plus Senning procedures and 12 Rastelli plus Senning procedures). Five patients were not candidates for the double switch. Before the double switch, 6 patients required pulmonary artery banding and 10 had functioning systemic to pulmonary artery or cavopulmonary shunts.

RESULTS

There was no early or late mortality. Two patients required pacemaker implantation, both later regained normal sinus rhythm. Tricuspid valve function improved in all patients except one. Moderate left ventricular dysfunction developed 5 months postoperatively in 1 patient.

CONCLUSIONS

The double switch operation can be performed in selected patients with minimal early morbidity and mortality. Longer follow-up is necessary to determine whether this complex approach is indeed warranted.

Decision-making and outcomes of prolonged ICU stays in seriously ill patients

BACKGROUND

Despite concern about the high costs and the uncertain benefit of prolonged treatment in the intensive care unit (ICU), there has been little research examining decision-making and outcomes for patients with prolonged ICU stays.

OBJECTIVES

To evaluate decision-making and outcomes for seriously ill patients with an ICU stay of at least 14 days.

DESIGN

A prospective cohort study.

SETTING

Five teaching hospitals.

PARTICIPANTS

Seriously ill patients enrolled in the Study To Understand Prognoses and Preferences for Risks and Outcomes of Treatments (SUPPORT).

MEASUREMENT

Patients, their surrogate decision-makers, and their physicians were interviewed about prognosis, communication, and goals of medical care. Based on age, diagnoses, comorbid illnesses, and acute physiology data, the SUPPORT Prognostic Model provided estimates of 6-month survival on study days 1, 3, 7, and 14. Hospital costs were estimated from hospital billing data.

RESULTS

Of the 9105 patients enrolled in SUPPORT, 1494 (16%) had ICU stays of 14 days or longer. The median length of stay in an ICU was 4 days for the entire SUPPORT cohort and 35 days for patients who were treated in an ICU for 14 days or longer. Median hospital costs were $76,501 for patients who had ICU stays 14 days or longer and $10,916 for patients who did not have long ICU stays. Fifty-five percent of patients with long ICU stays had died by 6 months, and an additional 19% had substantial functional impairment. Among patients with ICU stays of at least 14 days, only 20% had estimates of 6-month survival that fell below 10% at any time during their hospitalization. For patients with long ICU stays, the mean predicted probability of 6-month survival was 0.46 on study Day 3 and 0.47 on study Day 14. Fewer than 40% of patients (or their surrogates) reported that their physicians had talked with them about their prognoses or preferences for life-sustaining treatment. Among the patients who preferred a palliative approach to care, only 29% thought that their care was consistent with that aim. Those who discussed their preferences for care with a physician were 1.9 times more likely to believe that treatment was in accord with their preferences for palliation (95% CI, 1.4-2.5)

CONCLUSIONS

Prolonged ICU stays were expensive and were often followed by death or disability. Patients reported low rates of discussions with their physicians about their prognoses and preferences for life-sustaining treatments. Many preferred that care focus on palliation and believed that care was inconsistent with their preferences. Patients were more likely to receive care consistent with their preferences if they had discussed their care preferences with their physicians.

Evaluation of the Agricultural Safety and Health Best Management Practices Manual

The Agricultural Safety and Health Best Management Practices (ASHBMP) Manual was developed as an alternative intervention tool to help identify and correct farmwork hazards. A modified pretest-posttest control group experimental design was used to test the effectiveness of the manual with three intervention groups and a control. Testing consisted of conducting baseline and post-intervention audits on 150 farms in Pennsylvania. Significant differences were found among groups of farmers who were given the ASHBMP Manual and those who were not given the manual. The results of the data analysis also showed a positive significant difference among farmers who reduced their farm hazard levels through use of the ASHBMP Manual over farmers who received the Control (traditional safety fact sheets). The data supports the conclusion that the ASHBMP Manual is an effective tool for helping farmers reduce workplace hazards.

Differential regulation of plastidial and cytosolic isoforms of peptide methionine sulfoxide reductase in Arabidopsis

We report the characterization of two members of a gene family from Arabidopsis that encode, respectively, cytosolic (cPMSR) and plastid-targeted (pPMSR) isoforms of the oxidative-stress-repair enzyme peptide methionine sulfoxide reductase. Overexpression of these proteins in Escherichia coli confirmed that each had PMSR enzyme activity with a synthetic substrate, N-acetyl-[(3)H]-methionine sulfoxide, or a biological substrate, alpha-1 proteinase inhibitor. The pPMSR was imported into intact chloroplasts in vitro with concomitant cleavage of its approximately 5-kD N-terminal signal peptide. The two PMSR isoforms exhibited divergent pH optima, tissue localization, and responses to developmental and environmental effects. Analysis of the Arabidopsis database indicated that there are probably at least two p-pmsr-like genes and three c-pmsr-like genes in the Arabidopsis genome. Expression of the p-pmsr genes and their protein products was restricted to photosynthetic tissues and was strongly induced following illumination of etiolated seedlings. In contrast, the c-pmsr genes were expressed at moderate levels in all tissues and were only weakly affected by light. Exposure to a variety of biotic and abiotic stresses showed relatively little effect on pmsr gene expression, with the exception of leaves subjected to a long-term exposure to the cauliflower mosaic virus. These leaves showed a strong induction of the c-pmsr gene after 2 to 3 weeks of chronic pathogen infection. These data suggest novel roles for PMSR in photosynthetic tissues and in pathogen defense responses in plants.

Patients' perceptions of physicians' recommendations for comfort care differ by patient age and gender

OBJECTIVE

To determine patient characteristics associated with patient and proxy perceptions of physicians' recommendations for life-prolonging care versus comfort care, and with acceptance of such recommendations.

DESIGN

Cross-sectional.

SETTING

Five teaching hospitals in Denver, Colo.

PATIENTS

We studied 239 hospitalized adults believed by physicians to have a high likelihood of dying within 6 months.

MEASUREMENTS AND MAIN RESULTS

Interviews with patients or proxies were conducted to determine perceptions of physicians' recommended goal of care and roles in decision making.

RESULTS

Patients' mean age was 66.6 years; 44% were women. In adjusted analysis, age greater than 70 years and female gender were associated with a higher likelihood of believing that comfort care had been recommended by the physician (odds ratio [OR], 3.70; 95% confidence interval [CI], 1.89 to 7.24; OR, 1.99; 95% CI, 1.04 to 3. 84, respectively). Patients and proxies gave substantial decision-making authority to physicians: 29% responded that physicians dominate decision making, 55% that decision making is equally shared by physicians and patients, and only 16% that patients make decisions. Increasing age was associated with an increased likelihood of believing that physicians should dominate decision making (P <.005).

CONCLUSIONS

Among patients with advanced illness, perceived comfort care recommendations were related to patient age and gender, raising concern about possible gender and age bias in physicians' recommendations. Although all patients and proxies gave significant decision-making authority to physicians, older individuals were more likely to give physicians decision-making authority, making them more vulnerable to possible physician bias.

Paranasal sinus surgery through a frontonasal flap in sedated, standing horses

OBJECTIVE

To report experience with paranasal sinus surgery through a frontonasal flap in sedated, standing horses.

STUDY DESIGN

Treatment of 10 horses with naturally occurring paranasal sinus disease through a frontonasal bone flap created with the horses standing.

ANIMALS

Ten adult horses.

METHODS

After restraint and sedation, local anesthetic was injected subcutaneously along the proposed incision line over the conchofrontal sinus and was instilled into the sinuses through a small hole created in the frontal bone. A 3-sided, rectangular, cutaneous incision that extended through the periosteum was created over the frontal and nasal bones. The incision was extended into the conchofrontal sinus using a bone saw, and the base of the flap, on the midline of the face, was fractured. The sinuses were explored, and the horse was treated for the disease encountered. The flap was repositioned; subcutaneous tissue and skin were sutured separately.

RESULTS

The horses had few signs of discomfort during creation of the bone flap and during disease treatment. Diseases encountered included inspissated exudate in the ventral conchal sinus (five horses), feed and exudate throughout the sinuses (one horse), occlusion of the nasomaxillary aperature (one horse), polyp (one horse), osteoma (one horse), and progressive ethmoidal hematoma (one horse).

CONCLUSION

In selected cases, surgery of the paranasal sinuses can be performed safely on sedated and standing horses through a frontonasal bone flap.

CLINICAL RELEVANCE

Performing surgery through a frontonasal bone flap with the horse standing and sedated, rather than anesthetized, eliminates risks and expense of general anesthesia.

Evaluation of the Farm and Agricultural Injury Classification Code and follow-up questionnaire

The Farm and Agricultural Injury Classification (FAIC) code was developed specifically to identify and classify all agricultural injuries of interest to agricultural safety and health professionals. The FAIC code overcomes fundamental problems of classifying agricultural-related injuries by grouping incidents into categories describing actual exposures encountered on farms and in agricultural work. The successful application of the FAIC code depends largely on a researcher's ability to obtain appropriate information to correctly use the code. The purpose of this research project was to: (1) compare data obtained through a newly developed FAIC follow-up questionnaire (FQ) with data from the Penn State Agricultural Injury Database (AID); and (2) test FAIC Code utility, reliability, and construct validity with agricultural safety and health professionals. The FQ improved classification of 57% of cases in the Penn State AID. A majority of agricultural health and safety professionals understood and used the FAIC coding system, without training, to code an average of 75% of the test cases the same as the researcher. A large majority of the professionals that participated in this study judged the FAIC code and the accompanying materials to be very useful.

Computerized reminders for five preventive screening tests: generation of patient-specific letters incorporating physician preferences

Compliance with preventive screening tests is inadequate in the United States. We describe a computer based system for generating reminder letters to patients who may have missed their indicated screening tests because they do not visit a provider regularly or missed their tests despite the fact that they do visit a provider. We started with national recommendations and generated a local consensus for test indications. We then used this set of indications and our electronic record to determine test deficiencies in our pilot pool of 3073 patients. The computer generated customized reminder letters targeting several tests. Physicians chose any patients who should not receive letters. The response rate for fecal occult blood (FOB) testing was 33% compared with an 18% historical compliance rate within the same community. FOB reminders generated improved test compliance. Test execution must be considered when commencing a program of screening test reminders.

Inhibition of yeast inositol phosphorylceramide synthase by aureobasidin A measured by a fluorometric assay

Inositol phosphorylceramide synthase (IPC synthase) is an essential and unique enzyme in fungal sphingolipid biosynthesis and is the target of the cyclic nonadepsipeptide antibiotic aureobasidin A. As a first step towards understanding the mechanism of aureobasidin A inhibition, we developed a fluorometric HPLC assay for IPC synthase using the Saccharomyces cerevisiae enzyme and the fluorescent substrate analog 6-[N-(7-nitro-2,1, 3-benzoxadiazol-4-yl)amino]-hexanoyl ceramide (C(6)-NBD-cer). The kinetic parameters for C(6)-NBD-cer were comparable to those for the synthetic substrate N-acetylsphinganine used previously. Aureobasidin A acted as a tight-binding, non-competitive inhibitor with respect to C(6)-NBD-cer and had a K(i) of 0.55 nM.