Treatment of relapsed/refractory severe aplastic anemia in children: Evidence-based recommendations

Severe aplastic anemia (SAA) is a rare potentially fatal hematologic disorder. Although overall outcomes with treatment are excellent, there are variations in management approach, including differences in treatment between adult and pediatric patients. Certain aspects of treatment are under active investigation in clinical trials. Because of the rarity of the disease, some pediatric hematologists may have relatively limited experience with the complex management of SAA. The following recommendations reflect an up-to-date evidence-based approach to the treatment of children with relapsed or refractory SAA.

Treatment of newly diagnosed severe aplastic anemia in children: Evidence-based recommendations

Severe aplastic anemia (SAA) is a rare potentially fatal hematologic disorder. Although overall outcomes with treatment are excellent, there are variations in management approach, including differences in treatment between adult and pediatric patients. Certain aspects of treatment are under active investigation in clinical trials. Because of the rarity of the disease, some pediatric hematologists may have relatively limited experience with the complex management of SAA. The following recommendations reflect an up-to-date evidence-based approach to the treatment of children with newly diagnosed SAA.

A chronic eyelid lesion in a child: multi-disciplinary approach to diagnosis, treatment and management of a highly atypical histiocytic lesion

Malignant histiocytic neoplasm with histiocytic sarcoma phenotype is a rare malignant neoplasm, distinguished by malignant cells with phenotypic characteristics of mature tissue histiocytes. Histiocytic sarcoma typically presents as a primary malignancy, although can also present as a secondary malignancy, and is rarely seen in the pediatric population. Due to the rarity of this condition, diagnosis of histiocytic sarcoma is difficult and considered a diagnosis of exclusion. We describe a unique case of a chronic upper eyelid lesion with biopsy findings of a highly atypical histiocytic neoplasm initially concerning for histiocytic sarcoma; however, after integration of clinical findings, non-progressive and quiescent molecular profile, concluded to be an atypical juvenile xanthogranuloma in a child treated with excision and observation alone. This report highlights the importance of an integrated team approach to diagnosis of unusual histiocytic neoplasms.

Diagnostic work-up for severe aplastic anemia in children: Consensus of the North American Pediatric Aplastic Anemia Consortium

The North American Pediatric Aplastic Anemia Consortium (NAPAAC) is a group of pediatric hematologist-oncologists, hematopathologists, and bone marrow transplant physicians from 46 institutions in North America with interest and expertise in aplastic anemia, inherited bone marrow failure syndromes, and myelodysplastic syndromes. The NAPAAC Bone Marrow Failure Diagnosis and Care Guidelines Working Group was established with the charge of harmonizing the approach to the diagnostic workup of aplastic anemia in an effort to standardize best practices in the field. This document outlines the rationale for initial evaluations in pediatric patients presenting with signs and symptoms concerning for severe aplastic anemia.

Diagnosis and treatment of pediatric myelodysplastic syndromes: A survey of the North American Pediatric Aplastic Anemia Consortium

BACKGROUND

Myelodysplastic syndromes (MDS) represent a group of clonal hematopoietic stem cell disorders that commonly progress to acute myeloid leukemia (AML). The diagnostics, prognostics, and treatment of adult MDS are established but do not directly translate to children and adolescents. Pediatric MDS is a rare disease, characterized by unique cytogenetics and histology compared with adult MDS, and often arises secondary to germline predisposition or cytotoxic exposures. Our objective was to highlight aspects of diagnosis/management that would benefit from further systematic review toward the development of clinical practice guidelines for pediatric MDS.

PROCEDURE

The North American Pediatric Aplastic Anemia Consortium (NAPAAC) is composed of collaborative institutions with a strong interest in pediatric bone marrow failure syndromes and hematologic malignancies. The NAPAAC MDS working group developed a national survey distributed to 35 NAPAAC institutions to assess data on (1) clinical presentation of pediatric MDS, (2) diagnostic evaluation, (3) criteria for diagnosis, (4) supportive care and treatment decisions, and (5) role of hematopoietic stem cell transplantation (HSCT).

RESULTS

Twenty-eight of 35 institutions returned the survey. Most centers agreed on a common diagnostic workup, though there was considerable variation regarding the criteria for diagnosis. Although there was consensus on supportive care, treatment strategies, including the role of cytoreduction and HSCT, varied across centers surveyed.

CONCLUSIONS

There is lack of national consensus on diagnosis and treatment of pediatric MDS. This survey identified key aspects of MDS management that will warrant systematic review toward the goal of developing national clinical practice guidelines for pediatric MDS.

Spectroscopic confirmation of a mature galaxy cluster at a redshift of 2

Galaxy clusters are the most massive virialized structures in the Universe and are formed through the gravitational accretion of matter over cosmic time¹. The discovery² of an evolved galaxy cluster at redshift z = 2, corresponding to a look-back time of 10.4 billion years, provides an opportunity to study its properties. The galaxy cluster XLSSC 122 was originally detected as a faint, extended X-ray source in the XMM Large Scale Structure survey and was revealed to be coincident with a compact over-density of galaxies² with photometric redshifts of 1.9 ± 0.2. Subsequent observations³ at millimetre wavelengths detected a Sunyaev-Zel'dovich decrement along the line of sight to XLSSC 122, thus confirming the existence of hot intracluster gas, while deep imaging spectroscopy from the European Space Agency's X-ray Multi-Mirror Mission (XMM-Newton) revealed⁴ an extended, X-ray-bright gaseous atmosphere with a virial temperature of 60 million Kelvin, enriched with metals to the same extent as are local clusters. Here we report optical spectroscopic observations of XLSSC 122 and identify 37 member galaxies at a mean redshift of 1.98, corresponding to a look-back time of 10.4 billion years. We use photometry to determine a mean, dust-free stellar age of 2.98 billion years, indicating that star formation commenced in these galaxies at a mean redshift of 12, when the Universe was only 370 million years old. The full range of inferred formation redshifts, including the effects of dust, covers the interval from 7 to 13. These observations confirm that XLSSC 122 is a remarkably mature galaxy cluster with both evolved stellar populations in the member galaxies and a hot, metal-rich gas composing the intracluster medium.

Hitomi X-ray studies of Giant Radio Pulses from the Crab pulsar

To search for giant X-ray pulses correlated with the giant radio pulses (GRPs) from the Crab pulsar, we performed a simultaneous observation of the Crab pulsar with the X-ray satellite Hitomi in the 2 - 300 keV band and the Kashima NICT radio observatory in the 1.4 - 1.7 GHz band with a net exposure of about 2 ks on 25 March 2016, just before the loss of the Hitomi mission. The timing performance of the Hitomi instruments was confirmed to meet the timing requirement and about 1,000 and 100 GRPs were simultaneously observed at the main and inter-pulse phases, respectively, and we found no apparent correlation between the giant radio pulses and the X-ray emission in either the main or inter-pulse phases. All variations are within the 2 sigma fluctuations of the X-ray fluxes at the pulse peaks, and the 3 sigma upper limits of variations of main- or inter-pulse GRPs are 22% or 80% of the peak flux in a 0.20 phase width, respectively, in the 2 - 300 keV band. The values become 25% or 110% for main or inter-pulse GRPs, respectively, when the phase width is restricted into the 0.03 phase. Among the upper limits from the Hitomi satellite, those in the 4.5-10 keV and the 70-300 keV are obtained for the first time, and those in other bands are consistent with previous reports. Numerically, the upper limits of main- and inter-pulse GRPs in the 0.20 phase width are about (2.4 and 9.3) ×10^-11 erg cm^-2, respectively. No significant variability in pulse profiles implies that the GRPs originated from a local place within the magnetosphere and the number of photon-emitting particles temporally increases. However, the results do not statistically rule out variations correlated with the GRPs, because the possible X-ray enhancement may appear due to a > 0.02% brightening of the pulse-peak flux under such conditions.

Development of Electronic Chemotherapy Roadmaps for Pediatric Oncology Patients

A chemotherapy roadmap is a summary of the chemotherapy plan for a pediatric oncology patient. Chemotherapy roadmaps exist as paper documents for most, if not all, pediatric oncology programs. Paper chemotherapy roadmaps are associated with risks that can negatively affect the safety of the chemotherapy process. This institution explored the feasibility of converting paper chemotherapy roadmaps into an electronic form. The pediatric information systems team developed an innovative computer application that can generate electronic chemotherapy roadmaps, and the pediatric oncology program established a novel workflow that can operationalize them. Electronic chemotherapy roadmaps have been produced for 36 treatment protocols, and 369 electronic chemotherapy roadmaps have been used for 352 pediatric oncology patients. They have functioned as designed and have not had any unintended effects. In the 5 years after their implementation, the average proportion of patient safety events involving paper or electronic chemotherapy roadmaps decreased by 78.7%. This report is the first to demonstrate the feasibility of creating and implementing electronic chemotherapy roadmaps. Continued expansion of the current library will be necessary to formally test the hypothesis that electronic chemotherapy roadmaps can decrease the risks associated with their paper counterparts and increase the safety of the chemotherapy process.

Copy number gains in EGFR and copy number losses in PTEN are common events in osteosarcoma tumors

BACKGROUND

Osteosarcoma cell lines and tumors have been shown to express epidermal growth factor receptor (EGFR) and harbor amplifications at the EGFR locus. In this study, the authors further analyzed the genomic features of EGFR in osteosarcoma tumors and investigated whether they correlate with phosphatase and tensin homolog (PTEN) expression and copy number status.

METHODS

EGFR and PTEN expression was assessed by immunohistochemistry (n = 28), and copy number alterations at the EGFR and PTEN loci were surveyed using Affymetrix (Santa Clara, Calif) 50K single nucleotide polymorphism (SNP) arrays (n = 31) and fluorescence in situ hybridization (FISH) (n = 27). The EGFR tyrosine kinase domain was sequenced to survey for activating mutations (n = 34). In addition, EGFRvIII expression was assessed using reverse transcriptase polymerase chain reaction (n = 24). Results were correlated with available clinical information on 59 patients, with a median age of 14.1 years (range, 5-23 years) and median follow-up of 4.4 years.

RESULTS

EGFR expression was detected in the majority of osteosarcoma tumors surveyed (23 of 28; 82%). SNP arrays revealed evidence of frequent copy number gains at 7p11.2 and losses at 10q23.21. A sizeable subset (16 of 27 cases; 59%) showed gains at the EGFR locus using FISH (amplification in 4 of 27 [15%] and balanced chromosome 7 polysomy in 12 of 27 [44%]), and 12 cases showed deletions at the PTEN locus (biallelic deletions in 4 of 27 [15%] and monoallelic deletion in 9 of 27 [33%]). No activating mutations in the EGFR tyrosine kinase domain, EGFRvIII expression, or association with clinical findings were detected.

CONCLUSIONS

EGFR expression and genomic gains at the EGFR locus are prevalent in osteosarcoma tumors, which also commonly harbor deletions at the PTEN locus.

Postductal origin of the left carotid, left subclavian, and aberrant retroesophageal right innominate arteries in truncus arteriosus with interrupted aortic arch

A neonate presented to the C.S. Mott Children's Hospital at the University of Michigan with truncus arteriosus and interrupted left aortic arch, with associated postductal origin of the left carotid, left subclavian, and aberrant retroesophageal right innominate arteries. In addition, the patient was diagnosed with DiGeorge syndrome. This unique anomaly has not been previously reported. The anatomy, pathophysiology, embryology, and successful surgical management of this anomaly are reviewed in this report.

Evidence-based referral results in significantly reduced mortality after congenital heart surgery

OBJECTIVE

Significant interinstitutional variation in mortality after congenital heart surgery has been demonstrated. Noting an association between reduced mortality and higher volume, a center with a small annual case volume began in August 1998 to selectively refer to high-volume surgical centers based on published or "apparent" low mortality rates for specific cardiac lesions. This study was undertaken to evaluate the effect of evidence-based referral in this practice.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort comparison over a 10-year period for a small Midwestern pediatric cardiology practice. The institutional database was retrospectively reviewed for children (<18 years) undergoing surgery from August 1992 to July 2002. Data were divided into 3 time periods (August 1992 to July 1995, period 1; August 1995 to July 1998, period 2; and August 1998 to July 2002, period 3). Hospital discharge abstract data from 5 states (California, Illinois, Massachusetts, Pennsylvania, and Washington) in 1992, 1996, and 1998 provided contemporaneous benchmarks. Risk adjustment was performed using the Risk Adjustment in Congenital Heart Surgery-1 method. Risk category, age at surgery, prematurity, and major noncardiac structural anomaly were entered into a multivariate logistic regression model to compare in-hospital mortality adjusting for case-mix differences.

RESULTS

A total of 514 congenital heart surgical cases were identified from August 1992 to July 2002; 507 cases (98.6%) were assigned to a risk category and analyzed further. Unadjusted in-hospital mortality rates were 9.3% in period 1, 5.9% in period 2, and 1.3% in period 3. Unadjusted mortality rates for cases from benchmark data were 6.4% in 1992, 4.8% in 1996, and 3.7% in 1998. Risk adjusted mortality was comparable to the benchmark data in periods 1 and 2, but superior outcomes (odds ratio = 0.24) were demonstrated in period 3.

CONCLUSIONS

Evidence-based referrals from a small-volume pediatric cardiac center to large-volume institutions resulted in a reduction in mortality after congenital heart surgery.

Distribution of plutonium particles in the lungs of Mayak workers

Lung tissues from workers at the Mayak Production Association were examined to determine the distribution of plutonium (Pu) activity in various lung compartments. Stereological sampling methods and autoradiography were used. Pu particles were identified by microscopic examination of autoradiographs and localised in one of six normal anatomic sites and two sites of fibrosis (parenchymal, non-parenchymal). Particle activity was determined by counting the number of tracks emanating from the particles. Over 50% of the Pu activity was localised in sites of fibrosis, which had significantly higher than average activity for the lung. Over 40% of the activity was in lung parenchyma. Activity in the bronchovascular interstitium was significantly lower than average. These results support the hypothesis that Pu activity is not uniformly distributed in the lung, with long-term retained particles concentrated in scars of the lung. The results may significantly affect estimates of dose from inhaled Pu.

Cosmological constraints from Chandra observations of galaxy clusters

Chandra observations of rich, relaxed galaxy clusters allow the properties of the X-ray gas and the total gravitating mass to be determined precisely. Here, we present results for a sample of the most X-ray luminous, dynamically relaxed clusters known. We show that the Chandra data and independent gravitational lensing studies provide consistent answers on the mass distributions in the clusters. The mass profiles exhibit a form in good agreement with the predictions from numerical simulations. Combining Chandra results on the X-ray gas mass fractions in the clusters with independent measurements of the Hubble constant and the mean baryonic matter density in the Universe, we obtain a tight constraint on the mean total matter density of the Universe, Omega(m), and an interesting constraint on the cosmological constant, Omega(Lambda). We also describe the 'virial relations' linking the masses, X-ray temperatures and luminosities of galaxy clusters. These relations provide a key step in linking the observed number density and spatial distribution of clusters to the predictions from cosmological models. The Chandra data confirm the presence of a systematic offset of ca. 40% between the normalization of the observed mass-temperature relation and the predictions from standard simulations. This finding leads to a significant revision of the best-fit value of sigma(8) inferred from the observed temperature and luminosity functions of clusters.

Recent advances in P450 research

P450 enzymes comprise a superfamily of heme-containing proteins that catalyze oxidative metabolism of structurally diverse chemicals. Over the past few years, there has been significant progress in P450 research on many fronts and the information gained is currently being applied to both drug development and clinical practice. Recently, a major accomplishment occurred when the structure of a mammalian P450 was determined by crystallography. Results from these studies will have a major impact on understanding structure-activity relationships of P450 enzymes and promote prediction of drug interactions. In addition, new technologies have facilitated the identification of several new P450 alleles. This information will profoundly affect our understanding of the causes attributed to interindividual variations in drug responses and link these differences to efficacy or toxicity of many therapeutic agents. Finally, the recent accomplishments towards constructing P450 null animals have afforded determination of the role of these enzymes in toxicity. Moreover, advances have been made towards the construction of humanized transgenic animals and plants. Overall, the outcome of recent developments in the P450 arena will be safer and more efficient drug therapies.

Evidence for the biosynthesis of bryostatins by the bacterial symbiont "Candidatus Endobugula sertula" of the bryozoan Bugula neritina

The marine bryozoan, Bugula neritina, is the source of the bryostatins, a family of macrocyclic lactones with anticancer activity. Bryostatins have long been suspected to be bacterial products. B. neritina harbors the uncultivated gamma proteobacterial symbiont "Candidatus Endobugula sertula." In this work several lines of evidence are presented that show that the symbiont is the most likely source of bryostatins. Bryostatins are complex polyketides similar to bacterial secondary metabolites synthesized by modular type I polyketide synthases (PKS-I). PKS-I gene fragments were cloned from DNA extracted from the B. neritina-"E. sertula" association, and then primers specific to one of these clones, KSa, were shown to amplify the KSa gene specifically and universally from total B. neritina DNA. In addition, a KSa RNA probe was shown to bind specifically to the symbiotic bacteria located in the pallial sinus of the larvae of B. neritina and not to B. neritina cells or to other bacteria. Finally, B. neritina colonies grown in the laboratory were treated with antibiotics to reduce the numbers of bacterial symbionts. Decreased symbiont levels resulted in the reduction of the KSa signal as well as the bryostatin content. These data provide evidence that the symbiont E. sertula has the genetic potential to make bryostatins and is necessary in full complement for the host bryozoan to produce normal levels of bryostatins. This study demonstrates that it may be possible to clone bryostatin genes from B. neritina directly and use these to produce bryostatins in heterologous host bacteria.

The use of a high-volume screening procedure to assess the effects of dietary flavonoids on human cyp1a1 expression

We examined the effects of several agents, including dietary flavonoids, on CYP1A1 expression utilizing a recently developed high-throughput screening system for assessing human cytochrome P450 (CYP) induction. HepG2 cells, stably integrated with regulatory regions of human CYP1A1, were treated with resveratrol, apigenin, curcumin, kaempferol, green tea extract (GTE), (-)-epigallocatechin gallate (EGCG), quercetin, and naringenin. Of these flavonoids, resveratrol produced the greatest increase in CYP1A1-mediated luciferase activity (10-fold), whereas GTE, apigenin, curcumin, and kaempferol produced 2- to 3-fold increases in activity. Compared with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), omeprazole, or benzanthracene, where increases in luciferase activity ranged from 12- to 35-fold, these flavonoids exhibited weak agonist activity. The remaining compounds, EGCG, quercetin, and naringenin, produced negligible effects. Cotreatment of cells with TCDD and GTE, naringenin, and apigenin resulted in 58, 77, and 74% reductions, respectively, in TCDD-mediated CYP1A1 induction, indicating that these flavonoids exhibit potential antagonist activity toward the aryl hydrocarbon (Ah) receptor. Furthermore, results also suggest that GTE and apigenin possess Ah receptor antagonist and weak agonist activities. Thus, we have shown that a 96-well plate assay allowing high-throughput screening for P450 induction in less than 24 h was efficient in determining the effects of flavonoids on human CYP1A expression. Signal-to-noise ratios were low, and well-to-well and replicate variability was below 10%, allowing induction to be easily detected in this system. These features illustrate the reliability and feasibility of this high-volume screening system for identifying CYP inducers. Furthermore, results produced with the stable cell line were corroborated in HepG2 cells and primary cultures of human hepatocytes, suggesting that stably integrated cell lines harboring enhancer elements of P450 genes may be highly conducive to high-throughput screening.

Analgesic effect of the transdermal fentanyl patch during and after feline ovariohysterectomy

OBJECTIVE

To evaluate the efficacy of the transdermal fentanyl patch in relieving perioperative pain and stress associated with ovariohysterectomy in cats.

STUDY DESIGN

Prospective laboratory trial.

ANIMALS

Twenty-four female, purpose-bred cats.

METHODS

Each cat was randomly assigned to groups 1-3. Group 1 received a 25-microg/h transdermal fentanyl patch only. Group 2 received the patch and anesthesia. Group 3 received anesthesia only. Patches were left in place for 72 hours. Rectal temperature, heart rate, respiratory rate, indirect blood pressure, blood glucose, serum cortisol concentration, plasma fentanyl concentration, pain score, and excitement/sedation score were monitored at prescribed intervals over an 81-hour period. Cats from groups 1-3 were reassigned to groups 4 and 5. Group 4 received the patch, anesthesia, and an ovariohysterectomy. Group 5 received anesthesia and an ovariohysterectomy only. The study period and monitored parameters were the same as for groups 1-3.

RESULTS

Serum cortisol concentrations were significantly lower in group 4 than group 5 during the surgical and early postsurgical time periods. A similar effect was noted in blood glucose concentrations during the surgical period. Rectal temperature was significantly higher in group 2 when comparing all anesthetized groups during the early postsurgical period. Pain scores were significantly higher in groups 4 and 5 than in groups 2 and 3 during the early postsurgical period. There was no significant difference in pain scores between groups 4 and 5 during this period, however.

CONCLUSIONS

The transdermal fentanyl patch affects biochemical markers of perioperative pain and stress associated with ovariohysterectomy in cats, attenuating rises in serum cortisol and blood glucose concentrations during the surgical and early postsurgical periods.

CLINICAL RELEVANCE

The transdermal fentanyl patch is effective in alleviating perioperative pain and stress associated with ovariohysterectomy in cats as evidenced by attenuated rises in cortisol and blood glucose concentrations in cats that were operated on and treated with the patch.

Hard X-Ray Emission from Elliptical Galaxies and Its Contribution to the X-Ray Background

We explore the implications of the discovery of hard, power-law X-ray sources in the spectra of nearby elliptical galaxies for the origin of the X-ray background (XRB). The spectra of these sources are consistent with models of thermal bremsstrahlung emission from low radiative efficiency accretion flows around central supermassive black holes and are unique in that they approximately match the spectrum of the hard XRB. If such sources, with luminosities consistent with those observed in nearby elliptical galaxies, are present in most early-type galaxies, then their integrated emission may contribute significantly to the XRB. These sources may also contribute to the hard source counts detected in deep X-ray surveys.

Tissue reactivity to poliglecaprone 25 in the feline linea alba

OBJECTIVE

To use poliglecaprone 25 for all ligations and closure in routine feline ovariohysterectomies and evaluate maintenance of tissue approximation and tissue reaction to the suture.

STUDY DESIGN

Prospective, descriptive study.

ANIMALS

Twenty four female cats.

METHODS

Ovariohysterectomies were performed in all cats. Abdominal incisions were inspected on days 1, 3, 7, 14, and 28 for dehiscence and swelling. All cats were euthanatized postoperatively, group 1 on day 7; group 2 on day 14; and group 3 on day 28. The peritoneal cavity was inspected for adhesions and all abdominal incisions were collected en bloc. Each linea alba was histologically evaluated and the inflammatory reaction was characterized.

RESULTS

Dehiscence did not occur in any of the 24 cats. The incisional swelling on day 1 was significantly smaller than on day 7, and the swelling on day 14 was significantly smaller than on days 1, 3, and 7 (P < .05). Intra-abdominal adhesions were found in all groups with the greatest number associated with the peritoneum at the incision site. Tissue reactions in group 1 were pyogranulomatous or fibromononuclear, group 2 were granulomatous or fibromononuclear, and group 3 were pyogranulomatous, granulomatous, fibromononuclear or fibrous. Eosinophilic infiltration was seen in 3 of the 8 cats in group 1.

CONCLUSIONS

Incisional swelling and inflammatory reactions seen with poliglecaprone 25 were consistent with those anticipated after implantation of suture in a surgically created wound.

CLINICAL RELEVANCE

Poliglecaprone 25 appears to be an acceptable suture for use in feline ovariohysterectomy. It causes a relatively short-lived inflammatory response.

Changes in cortisol concentration in response to stress and postoperative pain in client-owned cats and correlation with objective clinical variables

OBJECTIVE

To identify clinical variables that indicate postoperative pain in cats after ovariohysterectomy in a veterinary hospital setting.

ANIMALS

40 cats.

PROCEDURE

Cats were anesthetized and ovariohysterectomized by senior veterinary students. Butorphanol (0.1 mg/kg [n = 20] or 0.3 mg/kg [20] of body weight) was administered IM after surgery. Blood samples were obtained before, during, and after the anesthetic period for measurements of PCV and blood glucose and cortisol concentrations. Clinical variables measured included heart rate, systolic blood pressure, respiratory rate, and rectal temperature. Data for these variables were compared with changes in cortisol concentrations and with similar data-which was used as historical control data-obtained from 20 cats in another study (10 that had been ovariohysterectomized but had not received butorphanol and 10 that had only been anesthetized).

RESULTS

Surgical durations were longer in this study, and cats had higher cortisol concentrations, compared with historical control cats. Objective clinical variables did not consistently correlate with changes in cortisol concentration.

CONCLUSIONS

Cortisol concentration increased in response to surgical stress and pain. This response was greater in cats in which duration of surgery was longer.

CLINICAL RELEVANCE

The objective clinical variables evaluated in this study were not consistent indicators of pain in an uncontrolled, clinical situation.

Flexor carpi ulnaris (humeral head) muscle flap for reconstruction of distal forelimb injuries in two dogs

OBJECTIVE

To describe the use of the humeral head of the flexor carpi ulnaris muscle as a rotational flap for reconstruction of distal antebrachial, carpal, and metacarpal injuries in two dogs.

STUDY DESIGN

Description of clinical cases.

RESULTS

Local rotation of the humeral head of the flexor carpi ulnaris muscle provided coverage of the carpal and carpometacarpal bones and joint structures exposed by soft tissue avulsion.

CONCLUSIONS

The distal portion of the humeral head of the flexor carpi ulnaris muscle can be used as a local muscle flap.

CLINICAL RELEVANCE

Early soft tissue coverage of large wounds to the carpal and metacarpal regions can be accomplished without resorting to a more technically difficult procedure, such as a free vascularized flap transfer.

Extramedullary plasmacytoma in the trachea of a dog

A 10-year-old spayed female mixed-breed dog was examined because of acute inspiratory dyspnea. Radiography and tracheoscopy revealed a discrete, solitary mass originating from the membranous portion of the trachea at the level of the thoracic inlet. Tracheal resection and anastomosis were performed, and on histologic examination of the resected tissue, extramedullary plasmacytoma was diagnosed. Although tracheal tumors are rare in dogs, they should be considered during evaluation of dogs with signs of airway obstruction. Prognosis is excellent for dogs with extramedullary plasmacytoma in which surgical excision is complete.

Use of partial prostatectomy for treatment of prostatic abscesses and cysts in dogs

OBJECTIVE

To determine whether dogs had prostatic disease, urinary incontinence, or urinary tract infection 1 year after partial prostatectomy to treat prostatic abscesses and cysts.

DESIGN

Prospective study.

ANIMALS

20 male dogs with prostatic abscesses or cysts. Fifteen dogs had evidence of urinary tract infection. Only 8 dogs urinated normally; the remainder dribbled, had obstructions, or required medical treatment.

PROCEDURE

Partial prostatectomy was performed on each dog. Sexually intact dogs (n = 12) also were castrated.

RESULTS

None of the dogs had return of prostatic cystic enlargement or clinical signs of prostatic disease during the first year after surgery. Two dogs were euthanatized within 1 year after surgery, with 1 dog having prostatic enlargement and adenocarcinoma and 1 dog having unrelated lymphosarcoma. Fifteen dogs were continent. The remaining 5 dogs urinated normally but had intermittent and minor incontinence. Eleven dogs had no signs of infection 1 year after surgery, 5 had pyuria or positive urine bacteriologic culture results, 2 did not have urinalysis performed, and 2 were euthanatized.

CLINICAL IMPLICATIONS

Dogs with severe prostatic abscesses or cysts and infections can be successfully treated by partial prostatectomy with an ultrasonic surgical aspirator and castration, resulting in long-term disease resolution. Although most dogs with severe prostatic disease do not urinate normally before surgery, nearly all dogs resume normal micturition after partial prostatectomy. Postoperative results of partial prostatectomy appear to be better than those of previous drainage techniques for treatment of prostatic cavitary disease.

Repair of a facial defect with an interpolation skin flap in a cat

A 9-year-old domestic shorthair cat was referred for removal of a rostrally located fibrosarcoma on the face, which had previously recurred twice following excision. A wide excision was performed, using a neodymium:yttrium-aluminumgarnet (Nd:YAG) laser, resulting in a facial defect that could not be closed by primary suture. An interpolation skin flap was elevated, using skin from the side of the cat's face, and sutured in place over the defect. Recurrence of the tumor at the medial canthus of the left eye, which was observed 4 months after surgery, was treated by laser excision and cryotherapy. Other recurrences of the fibrosarcoma were not noticed for 2.5 years after referral, at which time the cat was euthanatized for other reasons. Necropsy revealed that the fibrosarcoma had not recurred. In this cat, an interpolation skin flap was useful in repairing a large rostral facial defect. Care should be taken when elevating this flap to preserve the palpebral nerve.

Indicators of postoperative pain in cats and correlation with clinical criteria

OBJECTIVE

To identify clinical indicators that may help identity postoperative pain in cats after ovariohysterectomy.

ANIMALS

Healthy, laboratory animal source cats.

PROCEDURE

Clinical indicators of pain were identified, and relief from pain in response to butorphanol was studied in 5 groups of cats. 10 cats had 1 hour of general anesthesia only, followed by recovery without additional medication. 10 cats had general anesthesia and ovariohysterectomy, followed by recovery without additional medication. 10 cats had general anesthesia, ovariohysterectomy, and postoperative administration of 0.1 mg of butorphanol/kg of body weight. Another 10 cats had general anesthesia, ovariohysterectomy, and postoperative administration of 0.3 mg butorphanol/kg. 10 cats received 0.1 mg of butorphanol/kg, IM, only. Samples and recorded data were obtained before, during, and after the anesthesia period. Clinical variables measured included heart rate, blood pressure, respiratory rate, rectal temperature, PCV, and blood glucose concentration. Results were compared with changes in norepinephrine, epinephrine, and cortisol concentrations.

RESULTS

Cats that did not receive analgesics had higher cortisol concentration than did cats without surgery and cats that received butorphanol after surgery. Systolic blood pressure measured by ultrasonic Doppler was found to be predictive of cortisol concentration, using a multiple linear regression model.

CONCLUSIONS

Cortisol concentration increased in response to surgical stress and pain, and this increase was diminished by use of butorphanol.

CLINICAL RELEVANCE

Systolic blood pressure was the best clinical predictor of postoperative pain.

Surgical creation of portacaval shunts during temporary intestinal arterial and venous occlusion in dogs

OBJECTIVE

To surgically create complete portacaval shunts in dogs during temporary arrest of intestinal arterial and portal venous blood flow.

DESIGN

Complete portacaval anastomoses were surgically created, and liver function was evaluated for 14 to 18 weeks after surgery.

ANIMALS

32 adult mixed-breed dogs of either sex.

PROCEDURE

Administration of deferoxamine and temporary intestinal arterial occlusion were used to minimize the intestinal cellular damage resulting from the complete, temporary arrest of portal venous blood flow during creation of the portacaval anastomosis. Side-to-side, appositional anastomoses ( > 2 cm diameter) were formed between the portal vein and caudal vena cava. Dogs were observed daily for signs of hepatic encephalopathy, and food intake was recorded. Body weight was recorded weekly. Preprandial plasma ammonia, serum urea nitrogen, and glucose concentrations and sulfobromophthalein retention were measured monthly. The dogs were euthanatized, and necropsy was performed 14 to 18 weeks after surgery.

RESULTS

30 of 32 dogs recovered without complications. Complete portosystemic shunting was documented by increased plasma ammonia concentration, decreased serum urea nitrogen and glucose concentrations, prolonged sulfobromophthalein retention (P < 0.01), and inspection at necropsy.

CONCLUSION

This method of providing temporary, complete arrest of portal venous blood flow was helpful in allowing accurate, appositional portacaval anastomoses to be created that remained patent for 14 to 18 weeks.

CLINICAL RELEVANCE

This method of providing temporary, complete arrest of portal venous blood flow may prove useful in clinical surgery when temporary arrest of portal blood flow is desired.

Sequence analysis identifies the proline dehydrogenase and delta 1-pyrroline-5-carboxylate dehydrogenase domains of the multifunctional Escherichia coli PutA protein

The PutA protein of Escherichia coli has two enzymatic activities: proline dehydrogenase (PDH) and delta 1-pyrroline-5-carboxylate dehydrogenase (P5CDH). It associates with the cytoplasmic membrane as PDH and P5CDH and with put control region DNA as put repressor. Reduction of the PutA flavin by proline, a PutA conformational change and association of PutA with membranes are coincident. The nucleotide base sequence of E. coli putA was determined, that of S. typhimurium putA was updated and the deduced PutA protein sequences were surveyed for catalytic domains and ligand binding sites. The two sequences were very similar (80.5% and 95% on the nucleic acid and protein levels, respectively). Residues 650 through 1130 of PutA were very similar to the sequences of P5C dehydrogenases and aldehyde dehydrogenases from both prokaryotes and eukaryotes. Glutamate 883 and cysteine 917 of PutA were conserved with the corresponding residues in P5C dehydrogenases and with those proposed to be active site residues in the aldehyde dehydrogenases. Those relationships suggest that gamma-glutamic semialdehyde, believed to equilibrate spontaneously with P5C, is the substrate for P5C dehydrogenases. Residues 340 through 590 of PutA were similar in sequence to proline dehydrogenases from Saccharomyces cerevisiae and Drosophila melanogaster. Limited similarities were also found between residues 315 through 357 of PutA and a consensus sequence near a putative active site and FAD-binding region shared by succinate dehydrogenase sequences from several organisms. Since residues 228 through 358 of PutA were similar in sequence to several serine-pyruvate aminotransferases, PutA is proposed to catalyze the hydrolysis of P5C (a Schiff's base intermediate) to gamma-glutamic semialdehyde. A carboxyl-terminal sequence that resembles a leucine zipper motif may be involved in association of PutA with put control region DNA.

Microcytosis and iron status in dogs with surgically induced portosystemic shunts

Microcytosis is common in dogs with congenital portosystemic shunts (PSS) and acquired liver disease. The objective of this study was to determine if microcytosis could be induced in normal dogs by surgical creation of PSS, and to characterize the changes in hematology and iron status. Hematocrit, mean cell volume, mean cell hemoglobin, and mean cell hemoglobin concentration decreased linearly from 45.5%, 69.1 fL, 22.8 g/dL and 33.1% to 39.5%, 55.9 fL, 17.8 g/dL and 31.9%, respectively, 18 weeks after creation of PSS. The erythrocyte count did not change, but red cell distribution widths indicated a shift to a heterogenous population with decreased volume. Mean cell volume and mean cell hemoglobin decreased rapidly after induction of PSS and were significantly (P < .05) different from presurgery values within 2 weeks. Serum iron and copper concentrations and total iron binding capacity were decreased in dogs with PSS. Liver iron concentration doubled after creation of PSS, with the majority of stainable iron located in Kupffer cells. The changes in erythrocyte indices and measures of iron status in dogs with surgically induced PSS were similar to those in dogs with congenital PSS. Microcystosis developed rapidly in dogs after induction of PSS. These results indicate that iron deficiency was not the cause of microcytosis in these dogs.

Circulating immunoreactive endothelin-1 in children with pulmonary hypertension. Association with acute hypoxic pulmonary vasoreactivity

To determine whether circulating levels of endothelin-1 (ET-1), a potent vasoconstrictor peptide, are elevated in children with pulmonary hypertension and related to the degree of hypoxic pulmonary vasoconstriction, we measured arterial and mixed venous plasma concentrations of immunoreactive ET-1 (irET-1) in 13 children during cardiac catheterization. Clinical diagnoses in seven children with pulmonary hypertension (PH) included chronic lung disease (four children), congenital heart disease after surgical repair (two children), and primary ("reactive") pulmonary hypertension (one child). Blood samples were simultaneously obtained from pulmonary artery (venous) and systemic arterial sites during baseline conditions. Plasma irET-1 was elevated in children with PH (12.3 +/- 3.4 versus 3.6 +/- 0.7 pg/ml, PH versus non-PH; p < 0.01). Arterial/venous irET-1 ratios in the PH group (1.1 +/- 0.2) were not different from those in the non-PH group. During acute hypoxia, mean Ppa increased from 27 +/- 3 to 40 +/- 5 mm Hg. Basal irET-1 correlated strongly with the degree of elevation of mean Ppa during acute hypoxia (r = 0.69; p < 0.02). We conclude that irET-1 levels are often elevated in children with PH, and they are strongly correlated with pulmonary vasoreactivity during acute hypoxia. Whether elevated irET-1 levels contribute directly to or are markers of altered pulmonary vascular tone and reactivity in children with PH remains speculative.

Apparent dietary protein requirement of dogs with portosystemic shunt

Current medical management of dogs with portosystemic shunt (PSS) includes dietary protein restriction. After establishment of baseline values, 32 dogs underwent portosystemic anastomosis to induce PSS. They were assigned to 1 of 4 dietary treatments, and given 11 or 24% crude protein (CP); 20% of the protein was derived from branched chain or aromatic amino acids. The apparent digestibility of CP and of total digestible energy were not affected by PSS. The apparent digestibility of fat decreased from 92% to 85% in dogs with PSS (P < 0.01). Across all diets, the apparent dietary protein requirement (ADPR) was 2.07 g of CP/kg of body weight/d in clinically normal dogs and 2.11 g of CP/kg/d after PSS. Dietary amino acid composition had no effect on ADPR. The ADPR for dogs fed the 11% protein diets was 1.69 g of CP/kg/d in clinically normal dogs and 1.62 g of CP/kg/d after PSS, whereas the ADPR in dogs fed the 24% protein diets was 3.94 g of CP/kg/d before PSS and 3.31 g of CP/kg/d after PSS. Serum total protein, urea nitrogen, and albumin concentrations were lower in dogs with PSS fed the 11% protein diets, compared with those fed the 24% protein diets. We conclude that there is no difference in ADPR in dogs with PSS; however, the low protein intake of 1.62 g of CP/kg/d appeared inadequate to maintain normal protein stores. Dietary protein that provides at least 2.1 g of CP/kg/d is recommended for dogs with PSS.

Cholelithiasis in dogs: 29 cases (1980-1990)

Medical records of 29 dogs with cholelithiasis were reviewed. Aged female small-breed dogs were overrepresented. Mean age was 9.5 years, and mean weight was 12 kg. Vomiting, anorexia, weakness, polyuria/polydipsia, weight loss, icterus, fever, and signs of abdominal pain were the most common clinical signs. Leukocytosis, neutrophilia with left shift, monocytosis, high activity of serum hepatic enzymes, hypoalbuminemia, and high concentrations of serum total bilirubin were common. Radiopaque choleliths were evident on abdominal radiography of 13 of 27 dogs. Microbial culturing of bile isolated organisms in 15 of 20 dogs. Gram-negative bacteria were most common. Surgery was performed in 22 dogs. Four dogs were treated medically, and 3 dogs were euthanatized without treatment. Surgical treatment consisted of cholecystectomy in 11 dogs, choledochotomy in 5 dogs, cholecystotomy in 4 dogs, and cholecystojejunostomy in 1 dog. Sphincter of Oddiotomy was performed in 1 dog. Five dogs had concurrent generalized peritonitis attributable to bile. Multiple choleliths were detected in most of the dogs. Choleliths were located in the gallbladder in 20 dogs and in the bile ducts in 14 dogs. The most common abnormalities of the gallbladder, identified histologically, were chronic cholecystitis, mucosal hyperplasia, and pericholecystic inflammation. The most common abnormalities of the liver were cholestasis, hepatocellular degeneration, and periportal fibrosis. Survival rate of dogs that underwent cholecystectomy tended to be higher (86%) than that of dogs treated via cholecystotomy (50%) or cholecystectomy in combination with choledochotomy (33%). Dogs that underwent medical treatment, abdominal exploratory, cholecystojenunostomy, choledochotomy, and sphincter of Oddiotomy died or were euthanatized because of redevelopment of clinical signs associated with cholelithiasis.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary arteriovenous malformation in the newborn: a familial case

Pulmonary arteriovenous malformation (PAVM) is a rare cause of cyanosis in the newborn with nine previously reported cases. Typical signs at presentation include cyanosis, murmur, and congestive heart failure. Abnormality on chest x-ray is common with cardiomegaly, oligemia, and focal pulmonary density. There is a male predominance, unlike older children and adults with PAVM. Familial cases of PAVM have been reported with Osler-Weber-Rendu syndrome. We report a familial case of PAVM presenting in the newborn.

Maximal voluntary work and cardiorespiratory fitness in patients who have had Kawasaki syndrome

To assess the natural history of Kawasaki syndrome and its effect on maximal voluntary work and cardiorespiratory fitness, we performed cycle ergometry testing in 47 patients who had had the syndrome. Forty-one patients performed maximal effort as judged by achievement of 95% predicted heart rate response. Oxygen consumption, carbon dioxide production, and minute ventilation were performed in 23 patients. There was no difference in maximal voluntary work (total work, mean power) or maximal oxygen consumption between case subjects and control subjects. There were no differences between patients with and those without aneurysms. Serial exercise studies were performed in 10 patients; of these, two with initially normal exercise study findings had decreased maximal voluntary work and oxygen consumption with ischemic changes, and both were at high risk for the development of stenotic or occlusive coronary arteries. The other eight patients had normal cardiorespiratory reserve and no ischemic changes with serial studies. These results suggest that patients have normal cardiorespiratory fitness after Kawasaki syndrome. With the development of ischemic heart disease, they may have decreased cardiorespiratory reserve. Serial evaluation of cardiorespiratory fitness may demonstrate ischemic heart disease.

Role of specific similarity in a medical diagnostic task

Three experiments are reported showing that diagnosis of skin disorders by medical residents and general practitioners was facilitated by similar cases previously seen in the same context. Diagnosis of similar cases was facilitated more than that of dissimilar cases in the same diagnostic category, demonstrating that facilitation was not solely due to activation of the diagnostic category as a whole. Because diagnosis was posed in a multiple-choice format that always included the correct diagnosis, the relative disadvantage of dissimilar items was not due to the unavailability of the category name. The similarity effect also occurred with 2-week delay between the initial case and the test cases. Variations in diagnostic procedure, ranging from giving a quick first impression to arguing for given alternative diagnoses before selection, did not interact with the effect of similarity. This result suggests that the similarity effect is not strongly dependent on a particular diagnostic strategy.

Surgical management of pharyngeal disorders in the dog and cat

Disorders of the pharynx are relatively uncommon in the dog and cat. There are a number of potential causes of pharyngeal problems, but the underlying presenting clinical sign is that of dysphagia. This chapter will discuss the differential diagnosis of dysphagia with emphasis on oropharyngeal swallowing disorders. A separate discussion of special considerations to be made in the placement of pharyngostomy tubes also will be presented.

Ventral approach to the pelvic canal in the female dog

A ventral approach to the pelvic canal by bilateral pubic and ischial osteotomy was performed in five female dogs. The entire urogenital tract could be exposed and easily manipulated through this approach. All animals were ambulatory within 24 hours. Clinical union had formed in three of the four osteotomies by the time of euthanasia (months 2-4) in all animals. Incomplete union in some osteotomies indicated that exercise should be restricted for at least 4 months after the procedure. The procedure was determined to be clinically useful when wide exposure of the entire female urogenital tract is desired.

Role of specific similarity in a medical diagnostic task

Three experiments are reported showing that diagnosis of skin disorders by medical residents and general practitioners was facilitated by similar cases previously seen in the same context. Diagnosis of similar cases was facilitated more than that of dissimilar cases in the same diagnostic category, demonstrating that facilitation was not solely due to activation of the diagnostic category as a whole. Because diagnosis was posed in a multiple-choice format that always included the correct diagnosis, the relative disadvantage of dissimilar items was not due to the unavailability of the category name. The similarity effect also occurred with 2-week delay between the initial case and the test cases. Variations in diagnostic procedure, ranging from giving a quick first impression to arguing for given alternative diagnoses before selection, did not interact with the effect of similarity. This result suggests that the similarity effect is not strongly dependent on a particular diagnostic strategy.

Treatment of trochanteric ulcers with cranial sartorius and rectus femoris muscle flaps

Five dogs with pressure ulcers over the greater trochanter were treated by debridement and transposition of the cranial part of the sartorius or the rectus femoris muscle. Both muscles had vascular anatomy that allowed transposition based on a major vascular pedicle. All wounds healed promptly by primary intention and no ulcer recurred. The cranial sartorius flap technique was easier to perform than the rectus femoris technique.

Reinstating study context produces unconscious influences of memory

Having read a word does more to benefit its later perceptual identification when many, rather than few, of the words in the test list have been previously read. Some have suggested that this proportion overlap effect is produced by an intentional use of recognition memory or recall in the perceptual identification task. Contrary to this account, we found that words that are easily recognized (words generated from an anagram at study) do not gain more from increasing overlap than do words that are poorly recognized (words read at study). These findings are problematic for claims that word perception relies on a module, such as a logogen system, that is separate from the rest of memory.

Identification and anatomic categorization of the vascular patterns to the pelvic limb muscles of dogs

The vascular patterns to pelvic limb muscles were studied in 6 dogs (12 limbs) to identify muscles most suitable for transposition in the treatment of large wounds. Gross dissection of injected specimens and angiography were used to identify the vascular pedicles. The vascular pedicles to several muscles were generally consistent, and any variations would not interfere with most muscle transfers. The cranial part of the sartorius, gracillis, semitendinosus, and rectus femoris muscles were identified as suitable candidates for transfer. The caudal part of the sartorius, cranial tibial, and long digital extensor muscles have segmentalized vascular patterns that would limit its arc of rotation.

Recall by expert medical practitioners and novices as a record of processing attention

Using recall of clinical protocols as a measure of expertise in medicine has yielded disappointingly small effects. Experiments using recall of clinical laboratory data are presented to provide an explanation. In one experiment, subjects either deliberately memorized or first diagnosed and then were incidentally asked for memory. With incidental instructions, experts recalled over twice as much data as did students, but with memorization instructions, student performance approximated that of experts. Experts also showed a large advantage over students in incidental recall of data that were not relevant to the problem solution. These results suggest that expert processing in this "discrete, independent inputs" domain requires effortful analysis with minimal reliance on default values, rather than relatively effortless pattern perception reported in highly visual areas of expertise. For this area, intentional memory is a misleading measure of expertise. However, incidental memory is a valuable measure of processing during diagnosis.