Cerebral Blood Flow and Marrow Diffusion Alterations in Children with Sickle Cell Anemia after Bone Marrow Transplantation and Transfusion

BACKGROUND AND PURPOSE

Hematopoietic marrow hyperplasia and hyperperfusion are compensatory mechanisms in sickle cell anemia. We have observed marrow diffusion and arterial spin-labeling perfusion changes in sickle cell anemia following bone marrow transplantation. We aimed to compare arterial spin-labeling perfusion and marrow diffusion/ADC values in patients with sickle cell anemia before and after bone marrow transplantation or transfusion.

MATERIALS AND METHODS

We reviewed brain MRIs from patients with sickle cell anemia obtained during 6 consecutive years at a children's hospital. Quantitative marrow diffusion values were procured from the occipital and sphenoid bones. Pseudocontinuous arterial spin-labeling perfusion values (milliliters/100 g of tissue/min) of MCA, anterior cerebral artery, and posterior cerebral artery territories were determined. Territorial CBF, whole-brain average CBF, and marrow ADC values were compared for changes before and after either bone marrow transplantation or transfusion. Bone marrow transplantation and transfusion groups were compared. Two-tailed paired and unpaired Student t tests were used; P < .05 was considered significant.

RESULTS

Fifty-three examinations from 17 patients with bone marrow transplantation and 29 examinations from 9 patients with transfusion were included. ADC values significantly increased in the sphenoid and occipital marrow following bone marrow transplantation in contrast to patients with transfusion (P > .83). Whole-brain mean CBF significantly decreased following bone marrow transplantation (77.39 ± 13.78 to 60.39 ± 13.62 ml/100 g tissue/min; P < .001), without significant change thereafter. CBF did not significantly change following the first (81.11 ± 12.23 to 80.25 ± 8.27 ml/100 g tissue/min; P = .47) or subsequent transfusions. There was no significant difference in mean CBF between groups before intervention (P = .22).

CONCLUSIONS

Improved CBF and marrow diffusion eventuate following bone marrow transplantation in children with sickle cell anemia in contrast to transfusion therapy.

Factors associated with treatment delays in pediatric refractory convulsive status epilepticus

OBJECTIVE

To identify factors associated with treatment delays in pediatric patients with convulsive refractory status epilepticus (rSE).

METHODS

This prospective, observational study was performed from June 2011 to March 2017 on pediatric patients (1 month to 21 years of age) with rSE. We evaluated potential factors associated with increased treatment delays in a Cox proportional hazards model.

RESULTS

We studied 219 patients (53% males) with a median (25th-75th percentiles [p₂₅-p₇₅]) age of 3.9 (1.2-9.5) years in whom rSE started out of hospital (141 [64.4%]) or in hospital (78 [35.6%]). The median (p₂₅-p₇₅) time from seizure onset to treatment was 16 (5-45) minutes to first benzodiazepine (BZD), 63 (33-146) minutes to first non-BZD antiepileptic drug (AED), and 170 (107-539) minutes to first continuous infusion. Factors associated with more delays to administration of the first BZD were intermittent rSE (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.14-2.09; p = 0.0467) and out-of-hospital rSE onset (HR 1.5, 95% CI 1.11-2.04; p = 0.0467). Factors associated with more delays to administration of the first non-BZD AED were intermittent rSE (HR 1.78, 95% CI 1.32-2.4; p = 0.001) and out-of-hospital rSE onset (HR 2.25, 95% CI 1.67-3.02; p < 0.0001). None of the studied factors were associated with a delayed administration of continuous infusion.

CONCLUSION

Intermittent rSE and out-of-hospital rSE onset are independently associated with longer delays to administration of the first BZD and the first non-BZD AED in pediatric rSE. These factors identify potential targets for intervention to reduce time to treatment.

Cardiac resynchronization therapy in women: US Food and Drug Administration meta-analysis of patient-level data

IMPORTANCE

Women were underrepresented in cardiac resynchronization therapy (CRT) trials for heart failure (making up about 20% of enrollees). Combining individual patient data from multiple clinical trials would enable assessment of CRT benefit in women.

OBJECTIVE

To evaluate whether women with left bundle branch block (LBBB) benefit from CRT-defibrillators (CRT-D) at a shorter QRS duration than men with LBBB do.

DESIGN, SETTING, AND PARTICIPANTS

Individual patient data were pooled from 3 CRT-D vs implantable cardioverter defibrillator (ICD) trials (4076 patients) enrolling predominantly patients with New York Heart Association (NYHA) class II heart failure and follow-up to 3 years. The effect of CRT-D compared with ICD on outcomes was assessed using random effects Cox proportional hazards.

MAIN OUTCOMES AND MEASURES

Time to heart failure event or death (primary) and death alone (secondary).

RESULTS

Women benefited from CRT-D more than men. The main difference occurred in patients with LBBB and a QRS of 130 to 149 milliseconds. In this group, women had a 76% reduction in heart failure or death (absolute CRT-D to ICD difference, 23%; hazard ratio [HR], 0.24, [95% CI, 0.11-0.53]; P < .001) and a 76% reduction in death alone (absolute difference 9%; HR, 0.24, [95% CI, 0.06-0.89]; P = .03), while there was no significant benefit in men for heart failure or death (absolute difference 4%; HR, 0.85 [95% CI, 0.60-1.21]; P = .38) or death alone (absolute difference 2%; HR, 0.86 [95% CI, 0.49-1.52]; P = .60). Neither women nor men with LBBB benefited from CRT-D at QRS shorter than 130 milliseconds, while both sexes with LBBB benefited at QRS of 150 milliseconds or longer.

CONCLUSIONS AND RELEVANCE

In this population of patients with primarily mild heart failure, women with LBBB benefited from CRT-D at a shorter QRS duration than men with LBBB. This is important because recent guidelines limit the class I indication for CRT-D to patients with LBBB and QRS of 150 milliseconds or longer. While guidelines do give a class IIa indication to patients with LBBB and a QRS of 120 to 149 milliseconds, the present findings are important to communicate because women are less likely to receive CRT-D than men are. This study exemplifies the potential public health and regulatory science value of combining data from multiple clinical trials submitted to the FDA.

Idiopathic hyperostosis of the calvaria in five young bullmastiffs

A new calvarial hyperostotic syndrome (CHS) in young bullmastiffs is described. Calvarial hyperostotic syndrome clinically resembles canine craniomandibular osteopathy (CMO) and human infantile cortical hyperostosis (ICH), but it is unique in that there is progressive and often asymmetric skull bone involvement, and the population affected appears to be only young, male bullmastiff dogs. Characteristic radiographic findings consist of cortical thickening of the calvaria with irregular, bony proliferation over the frontal, temporal, and occipital bones. Histopathological examination shows that the trabeculae of the calvarial diploë are thickened and contiguous with a sunburst-like pattern of subperiosteal trabeculae composed of woven and lamellar bone tissue, accompanied by loose fibrovascular tissue and a variable inflammatory response comprised predominantly of neutrophils. In 80% of the cases presented, the lesion was self-limiting. The etiology remains unknown; however, traumatic, neoplastic, and degenerative conditions do not appear to be primary factors in the etiopathogenesis of the syndrome. It may be that this syndrome has a familial component, similar to that described for CMO and ICH.

Surgical treatment of idiopathic pericardial effusion in the dog: 25 cases (1978-1993)

Twenty-five cases of canine idiopathic pericardial effusion are described. All were treated surgically and underwent thoracotomy and pericardectomy, with histopathological evaluation of the resected pericardial sac. No tumor, infection, granulation tissue, or foreign body was found. Thirteen of the 25 dogs were golden retrievers, and all were large or giant breeds. Three (12%) died in the immediate postoperative period, and four (16%) died within one year of signs possibly related to the original condition. Eighteen (72%) survived at least 18 months; seven died or were euthanized for reasons unrelated to pericardial effusion (median, 44 months); and 11 were still alive at last contact (median, 61 months).

Reliability model from the in vitro durability tests of a left ventricular assist system

A reliability test of the Novacor N100PC left ventricular assist system (LVAS) with valved conduits, including a pump/drive unit with compact controller and LVAS monitor was performed. The initial test objective was to demonstrate sufficient reliability for clinical use as a long-term circulatory support system. The subsequent objective, a test to failure, was intended to provide an assessment of the durability of the design and to determine the LVAS wearout modes. Testing began in April 1993 and was performed with 12 systems on gravity-feed mock circulatory loops. The pump/ drive units were submersed in body temperature saline for the duration of the test. Each of the LVAS units was operated at nominal afterloads of 75, 90, and 105 mm Hg, with test conditions varied to yield nominal pump outputs of 5.6, 7.1, and 8.3 L/min. Failure was defined as the inability of the LVAS to maintain an average pump output of 4 L/min or an average output pressure of 60 mm Hg. After 3 years, all systems remained on test, with durations of 2.3 to 3.0 years. Analysis of the testing to that date, using a constant hazard rate model, indicated a minimum demonstrated reliability of 94% at a 60% confidence level, or 86% at a 90% confidence level, for a 2 year mission time. This greatly surpasses the reliability level included in the STS-ASAIO Long-Term Mechanical Circulatory Support System Reliability Recommendation (80% reliability, 60% confidence level for a 1 year mission time). In the subsequent test-to-failure protocol, all systems ran failure-free for at least 3 years. System failures occurring at longer durations were caused by a single common cause: wear of the energy converter's armature support bearings and shafts. The wearout mode was gradual and could be diagnosed noninvasively before failure. An analysis using a Weibull model was performed, using the test durations of those devices that failed, those that were electively removed from test for analysis of the wear mode, and those that continued on test. As of April 1998, the test results showed a reliability, at a 60% confidence level, of >99.9% for a 1 year mission time, 99.5% for a 2 year mission, and 92.0% for a 3 year mission (>99.9%, 98.3%, and 85.9% for equivalent mission times, at a 90% confidence level). Systems continue on test after as long as 4.9 years.

Adjunctive corticosteroid therapy for tuberculosis: a critical reappraisal of the literature

An extensive, although largely forgotten, literature addresses the utility of adjunctive corticosteroid therapy in the management of tuberculosis. Corticosteroid therapy probably improves neurological outcomes of, and decreases mortality due to, tuberculous meningitis of moderate severity. Although therapy for tuberculous pericarditis is simplified (with less need for operative intervention) by adjunctive corticosteroid administration and there are fewer deaths, the incidence of subsequent constriction is not changed. The signs and symptoms of typical reactivation tuberculous pneumonia, tuberculous pleurisy, and probably primary tuberculous disease (with lymphadenopathy) seem to decrease rapidly with corticosteroid therapy, although no differences in final outcomes have been observed. Corticosteroid regimens used in most studies varied greatly in duration and dosage and generally caused significant side effects. Corticosteroids do not appear to diminish the efficacy of adequate antimycobacterial therapy. Adjunctive corticosteroid therapy appears to offer significant short-term but (other than for tuberculous meningitis and effusive pericarditis) minimal long-term benefit for patients with tuberculosis.

Does this patient have appendicitis?

Appendicitis is a common cause of abdominal pain for which prompt diagnosis is rewarded by a marked decrease in morbidity and mortality. The history and physical examination are at least as accurate as any laboratory modality in diagnosing or excluding appendicitis. Those signs and symptoms most helpful in diagnosing or excluding appendicitis are reviewed. The presence of a positive psoas sign, fever, or migratory pain to the right lower quadrant suggests an increased likelihood of appendicitis. Conversely, the presence of vomiting before pain makes appendicitis unlikely. The lack of the classic migration of pain, right lower quadrant pain, guarding, or fever makes appendicitis less likely. This article reviews the literature evaluating the operating characteristics of the most useful elements of the history and physical examination for the diagnosis of appendicitis.

Trilateral tumors in four different lines of transgenic mice expressing SV40 T-antigen

PURPOSE

A line of transgenic mice containing the simian virus (SV) 40 T-antigen (T-ag) gene driven by the beta-luteinizing hormone (BLH) promoter developed bilateral retinoblastoma and primitive neuroectodermal tumors (PNET) of the midbrain. Midbrain tumors arose from the subependymal layer of the cerebral aqueduct. Bilateral ocular and brain tumors ("trilateral") were found in three other SV40 T-ag transgenic murine lines containing different promoters (murine interphotoreceptor retinoid-binding protein (IRBP), human IRBP, and alpha A-crystallin). To gain insight into the regulatory mechanisms involved in central nervous system tumorigenesis, the authors examined brain tumors from four lines of SV40 T-ag mice with different promoters.

METHODS

Formalin-fixed brain tumors were examined from four lines of transgenic mice containing different promoters linked to the protein coding region of the enhancerless SV40 T-ag oncogene. Transgenes contained the following promoters: BLH, mouse 1.8-kb IRBP, human 1.3-kb IRBP, and alpha A-crystallin.

RESULTS

Mice with a 1.8-kb IRBP promoter develop retinal photoreceptor and pineal tumors. Intracranial tumors arising from the subependymal layer of the third ventricle also were observed. Mice with a 1.3-kb IRBP promoter exhibit bilateral retinal PNET and PNET originating from the subependymal layer of the third ventricle. Mice with the alpha A-crystallin promoter exhibit bilateral lens tumors and PNET of the midbrain.

CONCLUSIONS

Ocular tumors in these mice may be ascribed to the promoter-driven, tissue-specific expression of SV40 T-ag. The common finding of PNET arising from the subependymal layer of the diencephalon is unlikely to be promoter related. These findings indicate that a regulatory region specific to the subependymal layer of the cerebral aqueduct and third ventricle resides in the structural region of the SV40 T-ag gene.

Angioleiomyoma of the nasopharynx in a dog

A polypoid angioleiomyoma was surgically removed from the nasopharynx of a 1-year-old, male golden retriever. The polypoid mass recurred 4 months later and was again excised. There was no sign of regrowth 13 months postoperatively. This is, apparently, the first reported angioleiomyoma occurring in the dog.

Cost analysis of objective structured clinical examinations

BACKGROUND

The costs of objective structured clinical examinations (OSCEs) and other patient-centered examinations have not been well established. The published literature contains cost estimates ranging from $21 to over $1,000 per examinee. This wide range in cost estimates is due in part to both a lack of a consistent definition as to what should be included as an expense and a lack of understanding of how these expenses can be minimized.

METHOD

In 1993-94 the authors conducted a literature review and defined and subcategorized costs related to the production and implementation of an OSCE into costs for personnel, standardized patients (SPs), and administration. An analysis was undertaken of how each of the subcategory costs can be minimized.

RESULTS

Costs for physicians, patient trainers, support personnel, and data analysis are negligible if the personnel who perform these duties do so as part of their overall academic responsibilities. Costs for SPs can be minimized by developing a cadre of experienced patients as well as professional personnel who participate in a comprehensive program in which SPs are used in both teaching and evaluative modes. This contributes to the development of a psychometrically valid OSCE with a minimum number of stations and decreased costs. Administrative costs are fixed and not amenable to significant cost saving. A detailed cost analysis of a comprehensive OSCE given at the end of an Introduction to Clinical Medicine course at one institution is presented, illustrating the practical aspects of these cost-containment methods.

CONCLUSION

Based on these considerations it appears financially feasible for an individual academic institution to develop and implement an OSCE.

Severe pruritus associated with lymphoma in a dog

A dog with chronic pruritus that was refractory to antibiotic, corticosteroid, and antihistamine treatment was found to have lymphoma involving the spleen and associated lymph nodes. Pruritus rapidly resolved on removal of the tumor and recurred on reappearance. The association of generalized pruritus with an occult malignant process may be difficult to assess, but after excluding the more common causes of pruritus, a visceral malignancy should be considered.

Thymoma in two ferrets

A cranial mediastinal mass was observed radiographically in two 5-year-old adult male ferrets (Mustela putorius furo), both with histories of chronic episodic vomiting, dyspnea, and lethargy. Malignant lymphoma, a common neoplasm observed in ferrets, was considered the most likely diagnosis. Cardiomegaly and splenomegaly were also present. Histologically both mediastinal masses were composed of thymic epithelial cells and small lymphocytes, establishing a diagnosis of thymoma. Thymoma should now be included in the differential diagnosis of a cranial mediastinal mass in ferrets.

Chylous ascites in cats: nine cases (1978-1993)

Medical records of 9 cats with chylous ascites that underwent exploratory celiotomy were reviewed. In 7 cats, chylous ascites was associated with intra-abdominal neoplasia: 4 cats had an unresectable tumor (hemangiosarcoma, 3 cats; paraganglioma, 1 cat) within the mesenteric root; 2 had malignant lymphoma of the small intestine and mesenteric lymph nodes; and 1 had lymphangiosarcoma of the abdominal wall. In 2 cats, chylous ascites was associated with nonneoplastic diseases: 1 cat had severe biliary cirrhosis and an extrahepatic portosystemic shunt; the other had steatitis caused by vitamin E deficiency. Three cats were euthanatized or died at the time of surgery, and 5 cats were euthanatized within 3 months of surgery. One cat with malignant lymphoma responded well to chemotherapy and lived for 14 months after surgery.

Hepatic plasmacytoma and biclonal gammopathy in a cat

A 13-year-old castrated male domestic shorthair cat was evaluated because of weight loss, despite a good appetite. The most remarkable abnormality was a total serum protein concentration of 12.4 g/dl, with a globulin concentration of 9.4 g/dl. Serum protein electrophoresis revealed a biclonal spike in the gamma region. At necropsy, 2 discrete plasmacytomas were found in the liver, without bone marrow involvement or amyloidosis.

Surgical treatment of thymoma in cats: 12 cases (1987-1992)

Twelve cats with thymoma were treated by surgical excision of the tumor alone. None of the cats received radiotherapy or chemotherapy. Two cats died or were euthanatized during the immediate postoperative period: 1 because of postsurgical hemorrhage, and the other because of an associated fungal pleuritis. None of the remaining 10 cats developed evidence of local tumor recurrence or metastases. Six of the cats were alive after follow-up periods ranging from 6 to 36 months (mean, 21 months; median, 21 months). Three cats were euthanatized 18 months, 32 months, and 45 months following surgery for unrelated problems, and 1 cat died as a result of trauma sustained 62 months postoperatively. Myasthenia gravis developed postoperatively in 2 of the cats.

Analyzing and adjusting for variables in a large-scale standardized-patient examination

BACKGROUND

Structuring a clinical performance examination that uses standardized patients (SPs) for large groups of examinees often involves the use of two or more parallel forms of the examination with different SPs portraying the same case on the different forms. In addition, each form may be administered more than once on different days and/or in different locations.

METHOD

To determine the effects of critical variables, such as day of examination, time of day (AM/PM), which of two simultaneous forms were taken, and sequencing effects, a univariate nested factorial analysis of variance was conducted for each of four annual SP examinations (1990-1993) at the University of Texas Southwestern Medical School. The examinations were given to approximately 200 second-year students per year at the end of their Introduction to Clinical Medicine course, and were graded on a pass/fail basis.

RESULTS

Statistically significant differences were found for the following variables: (1) time of day (AM or PM) and day were significant but were inconsistent and of small magnitude; (2) sequencing for the first two stations was significant in each form of the examination and in all four years; and (3) form-within-case differences (i.e., differences between SPs) were significant between the two forms of the examination in each year of administration. To minimize the impacts of these variables, two mean equating formulas were applied to the scores. Few examinees' pass/fail status would have been affected by either adjustment.

CONCLUSION

The parallel-forms examination format is minimally affected by the variables evaluated and is a fair pass/fail assessment of a student's performance. Mean equating is a valuable tool in minimizing the possibly unfair impact of variables on pass/fail decisions for homogeneous student populations.

Esophageal plasmacytoma in a dog

A 14-year-old spayed female dog of mixed breeding had a 3-week history of regurgitation of food occasionally mixed with blood. An esophagram revealed a mass in the caudal portion of the esophagus. The mass was partially removed through esophagoscopy. Evaluation of light microscopy, immunoperoxidase technique, and electron microscopy was consistent with an esophageal plasmacytoma. Surgical excision of the esophageal plasmacytoma was performed. Dogs with esophageal plasmacytoma appear to have a good prognosis.

Brain stem abscesses: cure with medical therapy, case report, and review

A patient with a brain stem abscess that was cured with medical therapy alone is described. The English-language literature on brain stem abscesses is reviewed. Computed tomography (CT) and magnetic resonance imaging (MRI) have revolutionized the rapidity with which the diagnosis can be made and have markedly changed the prognosis for patients with brain stem abscesses. To my knowledge, all patients whose brain stem abscesses have been diagnosed by MRI or CT have survived although some have had neurological residuals. Patients are usually treated with surgical excision or aspiration along with antibiotics. Our patient was treated with medical therapy alone, and this case represents the fourth reported cure with this treatment modality. Medical therapy may be anticipated to cure patients with brain stem abscesses whose conditions are diagnosed expeditiously with CT or MRI techniques.

Histologically confirmed clinical toxoplasmosis in cats: 100 cases (1952-1990)

Tissue sections from 119 cats that died or were euthanatized (1952-1990) because of toxoplasmosis-like illness were reexamined for Toxoplasma gondii by direct microscopy and immunohistochemical staining with anti-T gondii serum. Clinical and pathologic data from 100 of these cats with histologically verified toxoplasmosis were then analyzed. Of these 100 cats, 36 were considered to have generalized toxoplasmosis, 26 predominantly pulmonary lesions, 16 abdominal, 2 hepatic, 1 pancreatic, 1 cardiac, 2 cutaneous, 7 neurologic, and 9 had neonatal toxoplasmosis. In 14 cats, concurrent microbial infections or other maladies were seen. Cats were 2 weeks to 16 years old (median, 2 years; mean, 4 years). Sixty-five cats were males and 34 were females; sex was not recorded for 1 cat. Of 67 cats that had rectal temperatures recorded, 49 (73%) had fever (40.0 to 41.7 C). Dyspnea, polypnea, and signs of abdominal discomfort were frequently observed. Toxoplasmosis had been confirmed antemortem in 8 cats; 4 had a serum antibody titer to T gondii of > or = 1:1,024; and T gondii had been found in cytologic evaluation of tracheal aspirates from 2 cats and pleural fluid from 1 cat, as well as in a biopsy specimen of a mesenteric lymph node from another. Of the 15 cats with T gondii serum-antibody titers determined by the Sabin-Feldman dye test, 6 had no antibody detected in 1:4 dilution of their serum. Indirect fluorescent antibody titers were found in 10 of 10 cats' sera tested. Forty-one eyes from 27 of the cats were examined microscopically. Twenty-two of the 27 cats (81.5%) had evidence of intraocular inflammation in one or both eyes. Multifocal iridocyclochoroiditis was the most common lesion and was seen in 18 (81.8%) of the cats with ophthalmitis. The ciliary body was the most often severely affected portion of the uvea. Of the 22 cats with ocular toxoplasmosis, T gondii was found in eyes of 10. Toxoplasma gondii was found in the retina of 5 cats, the choroid of 2, the optic nerve of 1, the iris of 3, and the ciliary body of 4. Toxoplasma gondii was identified in 80% of 55 brains, 70.0% of 90 livers, 76.7% of 86 lungs, 64.4% of 45 pancreata, 62.7% of 59 hearts, 45.8% of 72 spleens, 41.5% of 65 intestines, 17.7% of 61 kidneys, and 60.0% of 30 adrenal glands.

Neonatal toxoplasmosis in littermate cats

Toxoplasmosis was diagnosed histologically in 9 kittens and 1 queen from 5 liters. In litter 1, four 3-month-old Siamese kittens and the queen were affected. The queen died of generalized toxoplasmosis, and her kittens died or were euthanatized 20, 22, or 28 days later. In litter 2, two of 3 Abyssinian 4- and 4.5-month-old kittens died of toxoplasmosis. In litter 3, an Abyssinian, delivered by cesarean section, became ill 17 days after delivery, and died 2 days later because of toxoplasmic hepatitis and pneumonia. In litter 4, three kittens, approximately 1 month old, were shedding Toxoplasma gondii-like oocysts, and the organism was identified histologically in tissues of 1 of them. In litter 5, one 3-week-old kitten out of 4 became ill. Toxoplasma gondii-like oocysts were found in feces and T gondii organisms were found in histologic sections of tissues.

Gastritis caused by Aonchotheca putorii in a domestic cat

Aonchotheca putorii is a parasitic nematode of the stomach and small intestines of many wild mammals. Although A putorii has been found in domestic cats in Iowa, it has not been reported to be pathogenic. The parasite caused severe gastric and was associated with a gastric ulcer and secondary anemia in a 10-year-old domestic shorthair cat from Ohio. The source of infection was not determined. Surgical resection of the affected tissue resolved clinical signs. The importance of postoperative administration of an anthelmintic in the resolution of any remaining A putorii is unknown. Ivermectin was given empirically to this cat. It is not known whether, or at what dosage, ivermectin or any other anthelmintic is effective against A putorii.

Functional ectopic interstitial cell tumor in a castrated male cat

A 12-year-old male cat that had been castrated at 6 months of age was examined to determine the cause of urine spraying of 2 years' duration. The cat had acquired physical characteristics of a sexually intact male, and its serum testosterone concentration was greater than values expected for a castrated cat. Administration of a variety of medications did not halt urine spraying. At necropsy, an interstitial cell tumor was found in a remnant of a spermatic cord.

Semi-constitutive expression of an Arabidopsis thaliana alpha-tubulin gene

In Arabidopsis tissues, the pool of tubulin protein is provided by the expression of multiple alpha-tubulin and beta-tubulin genes. Previous evidence suggested that the TUA2 alpha-tubulin gene was expressed in all organs of mature plants. We now report a more detailed analysis of TUA2 expression during plant development. Chimeric genes containing TUA2 5'-flanking DNA fused to the beta-glucuronidase (GUS) coding region were used to create transgenic Arabidopsis plants. Second-generation progeny of regenerated plants were analyzed by histochemical assay to localize GUS expression. GUS activity was seen throughout plant development and in nearly all tissues. The blue product of GUS activity accumulated to the highest levels in tissues with actively dividing and elongating cells. GUS activity was not detected in a few plant tissues, suggesting that, though widely expressed, the TUA2 promoter is not constitutively active.

Unidentified Toxoplasma-like tissue cysts in the brains of three cats

Tissue cysts of an unidentified Toxoplasma-like parasite were found in three of 103 cats that were diagnosed histologically with toxoplasmosis-like illness at the Angell Memorial Animal Hospital, Boston, MA, between 1952 and 1991. Tissue cysts in these three cats were confined to the brain and two cats had concurrent lymphoid disorders. The tissue cysts of the unidentified parasite were about twice the size of Toxoplasma gondii tissue cysts.

Fatal toxoplasmosis in domestic rabbits in the USA

Three rabbits from two sources died after an acute illness characterized by fever, lethargy and diarrhea in one rabbit and no clinical signs in two rabbits. The most striking lesion in all three rabbits was foci of necrosis of the spleen and liver associated with massive presence of multiplying Toxoplasma gondii tachyzoites. The diagnosis was confirmed by specific staining with anti-T. gondii serum in an avidin-biotin complex immunohistochemical stain.

Preferential expression of an alpha-tubulin gene of Arabidopsis in pollen

The pool of tubulin protein in tissues of Arabidopsis is provided by the expression of multiple alpha-tubulin (TUA) and beta-tubulin genes. Whereas most tubulin genes are expressed in many tissues, previous evidence suggested that the TUA1 gene might be expressed primarily in pollen. We now report a detailed analysis of TUA1 expression during Arabidopsis development. In RNA from tissues of dissected flowers, TUA1 transcripts were detected only in stamens and mature pollen. Chimeric genes containing TUA1 5' flanking DNA fused to the beta-glucuronidase (GUS) coding region were used to create transgenic Arabidopsis plants. Plants containing a chimeric gene with 533 bp of 5' flanking sequence were analyzed by histochemical assay to localize GUS expression within the plant. The blue product of GUS enzyme activity accumulated very rapidly in postmitotic pollen grains. Much lower levels of GUS activity were detected in anthers with uninucleate pollen grains, in flower receptacles, and in a few vegetative tissues. Analysis of 5' deletions of the TUA1 promoter suggested that 97 bp of 5' flanking DNA is sufficient to drive GUS expression in pollen and young anthers, whereas at least 380 bp is required to detect GUS expression in the receptacle. Examination of the TUA1 promoter sequence revealed several motifs that are repeated within the TUA1 promoter and are similar to sequences in other pollen-specific promoters.

Intracranial meningioma with pulmonary metastasis in three dogs

Extracranial metastasis of primary central nervous system neoplasms is uncommon and has not been described in the dog. We report the clincopathologic features of intracranial meningioma with pulmonary metastasis in three dogs (case No. 1: 13-year-old castrated male Boxer dog; case No. 2: 14-year-old spayed female Dachshund; case No. 3: 6-year-old spayed female German Shepherd Dog). Case No. 1 presented with ataxia, lethargy, vomiting, and leaning and falling to the right, and had a transient remission following radiation and corticosteroid therapy; case No. 2 had a history of seizures that were unresponsive to primidone, left-sided postural reaction deficits, ataxia, and circling to the right; case No. 3 had only intermittent episodes of vomiting Computed tomography of case Nos. 1 and 2 revealed peripherally located homogeneous contrast-enhancing intracranial masses. Postmortem examination revealed intracranial masses with single or multiple pulmonary nodules in all three cases. Histologically, the intracranial and pulmonary masses were meningotheliomatous meningiomas with atypical features including brain infiltration, necrosis, nuclear atypia, prominent nucleoli, and moderate cell density. All of the primary meningiomas had low mitotic rates. The current interest in early diagnosis and aggressive clinical/surgical management of canine patients with meningioma and other primary central nervous system neoplasms will likely result in an increased detection of extracranial metastases.

Cystic papillary meningioma in the sella turcica of a dog

An 8-year-old spayed Scottish Terrier was examined because of a history of intermittent abnormal behavior that progressed to hind limb ataxia and eventually to recumbency with opisthotonos. X-Ray computed tomography revealed a radiolucent mass in the area of the hypothalamus. At necropsy, a suprasellar cystic papillary meni-ngioma was identified. The unusual clinical signs of disease and computed tomographic findings of this case complicated diagnosis.

Toxoplasma gondii-like schizonts in the tracheal epithelium of a cat

Toxoplasma gondii-like schizonts were found in tracheal epithelium of an 8-yr-old male cat. The parasites were located in parasitophorous vacuoles within the host cell cytoplasm, divided by schizogony, contained periodic acid-Schiff-positive granules, and reacted with anti-T. gondii serum but not with anti-Neospora caninum serum. Mature schizonts were 7.0 x 5.9 microns (5-10 x 4-10 microns; n = 22) and contained 4-16 merozoites. The merozoites were approximately 5 x 1 microns.

Mycobacterium kansasii infections in patients positive for human immunodeficiency virus

The experience with Mycobacterium kansasii infections in patients who are infected with human immunodeficiency virus (HIV) at Parkland Memorial Hospital in Dallas is presented, and the literature on such infections is reviewed. The absolute and relative paucity of reports of M. kansasii infections in HIV-positive patients is emphasized. M. kansasii infections in HIV-positive patients are classified as either pulmonary or disseminated. Evidence of the lack of therapeutic response in patients with disseminated infections and of the potential for therapeutic response in patients with infections limited to the lung is reviewed and documented. Other unresolved diagnostic and therapeutic issues concerning M. kansasii infections in HIV-positive patients are reviewed.

Distinctive unclassified mesenchymal tumor of the digit of dogs

Four examples of a mesenchymal tumor of undetermined histogenesis occurred in three mixed-breed dogs and one Yorkshire terrier. All tumors occurred as solitary, soft to firm, solid, tan, and ulcerated masses in the digits of dogs aged 11 to 15 years. The compact cellular tumor had cells with anisokaryotic round, oval, or irregular nuclei, some of which were multinucleated. The neoplastic cells appeared to arise in the tissue near the third phalanx in the area of dense collagenous trabeculae located proximal to the fat pad and sweat glands. The unclassifiable cells had some features of histiocytes by transmission electron microscopy, but failed to stain for lysozyme and alpha-1-antichymotrypsin, markers for monocyte-macrophage derived cells. Immunohistochemically, the cells stained for vimentin but not for cytokeratins, desmin, S-100 protein, epithelial membrane antigen, alpha-lactalbumin, lysozyme, alpha-1-antichymotrypsin, alpha-lactalbumin, casein, and heavy and light chain immunoglobulins. The combined findings of light and transmission electron microscopy and immunohistochemistry exclude tumor histogenesis from an epithelial cell, melanocyte, mast cell, plasma cell, Schwann cells, and Merkel cell.

Neuronal and glial properties of a murine transgenic retinoblastoma model

Antigenic properties of a murine transgenic model for hereditary retinoblastoma, induced by a chimeric gene coding for Simian virus 40 large T antigen, an oncogene that inactivates the retinoblastoma susceptibility gene product, were studied by immunohistochemistry. All transgenic mice develop bilateral intraocular retinal tumors in the inner nuclear layer with Homer Wright-like rosettes, and one quarter develop midbrain tumors resembling trilateral retinoblastoma. Cell lines TE-1 and TM-1 were established from intraocular and metastatic tumors, respectively. Intraocular tumors reacted with antibodies to neuron-specific enolase and synaptophysin, while vimentin, glial fibrillary acidic, and S-100 proteins were detected only in reactive glia derived from adjacent retina. The midbrain tumors showed weak reactivity to synaptophysin, and they blended with reactive astrocytes positive for glial markers. The tumors were negative for cytokeratins. Finally both derived cell lines expressed synaptophysin and individual neurofilament triplet proteins in immunofluorescence and Western blotting, supporting their essentially neuronal nature. The antigenic profile resembles human retinoblastoma, but differences in morphology and antigen distribution suggest a more close relationship to neurons of the inner nuclear layer than to photoreceptor cells.

Community-acquired pulmonary infections in a public municipal hospital in the 1980s

The relative and absolute incidences of community-acquired bacterial and tuberculous pulmonary infections, in patients admitted to a public municipal hospital, and the clinical and radiographic characteristics of these infections were retrospectively determined for the first time in 20 years. The data were compared to those previously reported in the literature. Such data were also specifically determined for alcoholics and compared to those found in nonalcoholics. The absolute numbers of infections due to pneumococci and anaerobes, and to tuberculosis, were not dissimilar to those reported in the literature, even though relatively few hemophilus infections were documented. The lack of Klebsiella sp infections was remarkable but not unexpected. Alcoholic patients had significantly higher rates of tuberculosis, cavitary disease, lung disease presumably due to anaerobes, and blood-culture-positive pneumonia. The relative concordance of our results for bacterial and tuberculous infections with those predicted from the published literature was striking. The high frequency of tuberculosis in our patients was particularly striking at a time when the incidence of tuberculosis nationwide, in patients without acquired immunodeficiency syndrome, has declined significantly.

Primitive neuroectodermal tumor of the midbrain in a murine model of retinoblastoma

The first heritable model of retinoblastoma was established by retina-specific expression of simian virus 40 T-antigen (SV40 T-ag) in transgenic mice. Bilateral, multifocal ocular tumors were observed in 100% of transgene-bearing mice. Central nervous system neoplasms occurred at a lower rate (27%) and represented the murine counterpart of human trilateral retinoblastoma. The authors characterized the transgenic brain tumors and found them to be primitive neuroectodermal tumors (PNET) of the midbrain. Murine brain tumors do not involve the pineal gland and most closely resemble undifferentiated suprasellar or parasellar tumors occasionally observed in human trilateral retinoblastoma. The murine malignancies arose from the subependymal cells of the cerebral aqueduct. Immunohistochemical and ultrastructural examination revealed that the transgenic brain tumors were undifferentiated and lacked all antigens associated with normal murine neuronal, glial, and ependymal cells.

Perivalvular extension of infection in patients with infectious endocarditis

Perivalvular extension of infection is a not-infrequent and potentially fatal complication of bacterial endocarditis. Because the efficacy of various modalities in the diagnosis of such complications is not well established, a selective review of the published literature on this issue is worthwhile. The electrocardiogram is the easiest study to obtain. It is quite specific in identifying perivalvular extension of infection when conduction system disease is demonstrated but has a low degree of sensitivity overall. Transthoracic two-dimensional echocardiography, transesophageal echocardiography, and color-flow Doppler echocardiography are the most practical and useful techniques for diagnosis of perivalvular extension of infection. Magnetic resonance imaging also appears to be an effective tool in this setting; however, because of a paucity of clinical data, its precise utility has not yet been determined. Nuclear medicine studies and computed tomography play a minimal role. Cardiac catheterization is as useful as the echocardiographic techniques but is invasive, not as readily available, and significantly riskier in terms of complications. An approach to the diagnosis of perivalvular extension of infection is proposed on the basis of the literature review.

A transgenic mouse model for trilateral retinoblastoma

We present a murine model of trilateral retinoblastoma. Ocular retinoblastoma and central nervous system tumors are observed in a line of mice formed by the transgenic expression of SV40 T-antigen. An oncogenic protein known to bind to the retinoblastoma gene product (p105-Rb) is specifically expressed within retinal cells in this model. All animals that carry this genetic alteration develop multifocal retinal tumors. Midbrain tumors are observed in 15% of ocular tumor-bearing animals, and these arise ventral to the cerebral aqueduct at the level of the pineal gland. Both ocular and central nervous system neoplasms are heritable in heterozygous offspring through 10 sequential generations of breeding. Retinal tumors display the gross appearance, invasive properties, light and electron microscopic features, and immunohistochemical staining characteristics of human retinoblastoma. The light and electron microscopic characteristics as well as immunocytochemical features of undifferentiated midline central nervous system neoplasms further correlate with human trilateral retinoblastoma. We postulate an alternative mechanism of retinoblastoma tumorigenesis that involves functional inactivation of retinoblastoma protein locally in the face of an intact retinoblastoma gene locus.

Chordoma in a cat

A chordoma within the deep musculature adjacent to C3 and C4 was excised from a 14-year-old castrated domestic cat. Metastatic chordoma developed in a prescapular lymph node 10 months later. At necropsy 11 months after complete excision of the primary tumor, metastases were found in both retropharyngeal lymph nodes.

Klebsiella pulmonary infections: occurrence at one medical center and review

Klebsiella pneumoniae is the species of aerobic gram-negative bacteria most commonly recognized as a cause of community-acquired pneumonia. The vast majority of articles concerning the epidemiology, frequency, and clinical and radiographic features of community-acquired pneumonias caused by this organism are over 20 years old. Experience with community-acquired pneumonias due to K. pneumoniae at one medical center over the last 20 years is reported and compared with the previously published literature. The recent experience at Parkland Memorial is quite similar to that in the literature. Salient features include the infrequency of K. pneumoniae as a cause of community-acquired pneumonia, the lack of specificity and sensitivity of most clinical and radiographic findings, and the similarity to and potential confusion with anaerobic pneumonitis and cavitary lung disease if only expectorated sputums are utilized for diagnosis in certain population groups such as alcoholics.

Feline muscular dystrophy with dystrophin deficiency

This is the first description of a dystrophin-deficient muscular dystrophy in domestic cats. The disorder appears to be of X-linked inheritance because it affected both males of a litter of four kittens. Immunoblotting and immunofluorescent detection of dystrophin showed dystrophin present in control cat muscle but no detectable dystrophin in either affected cat. The feline muscular dystrophy was progressive and histopathologically resembled human Duchenne/Becker muscular dystrophy except for the lack of fat infiltration and the presence of prominent hypertrophy of both muscle fibers and muscles groups in the feline disorder.

Nonangiogenic and nonlymphomatous sarcomas of the canine spleen: 57 cases (1975-1987)

The case records of and histopathologic findings in 57 dogs with nonangiogenic and nonlymphomatous splenic sarcomas were reviewed. Splenic neoplasms in these dogs included leiomyosarcoma, fibrosarcoma, undifferentiated sarcoma, liposarcoma, osteosarcoma, chondrosarcoma, myxosarcoma, rhabdomyosarcoma, and fibrous histiocytoma. The clinical signs associated with splenic sarcoma included anorexia or decreased appetite, abdominal distention, polydipsia, lethargy, vomiting, weight loss, and weakness. An abdominal mass was detected in 86% of the dogs by use of abdominal palpation (63%), and/or abdominal radiography (74%). The diagnosis was based on histopathologic findings in the spleen. Abdominal exploratory surgery was performed on 43 of the 57 dogs. Twenty-seven dogs were treated by splenectomy, and 16 were euthanatized at the time of surgery because of widespread metastatic lesions. Of the 14 dogs on which surgery was not performed, 11 were euthanatized on the basis of results of preoperative diagnostic tests, and the remaining 3 dogs had splenic neoplasms that were incidental findings at necropsy. Of the 27 surgically treated dogs, 5 died in the immediate postoperative period, 12 died or were euthanatized within 1 year after splenectomy, and only 5 dogs survived greater than or equal to 1 year. Three dogs were lost to follow-up evaluation, and 2 were still alive 6 and 7 months after surgery. The median survival time of the 22 dogs for which survival was known was 2.5 months. The median survival time for 11 dogs with no obvious metastasis at the time of splenectomy was 9 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Diffuse alveolar injury in two dogs

Proliferative interstitial pneumonia of undetermined cause was diagnosed in 2 dogs. The clinical signs in both dogs consisted primarily of acute onset, rapid breathing, and raspy lung sounds. Radiography revealed a diffuse increase in pulmonary alveolar density. In both dogs, the primary pathologic process was diffuse alveolar pneumocyte injury, and the pulmonary lesions were similar. Proliferation of type II pneumocytes (some of which were atypical mononucleated, and others multinucleated) was a prominent feature of the interstitial pneumonia. Because of the atypical features of some pneumocytes in such cases, biopsy findings may suggest a neoplastic process. Proliferative interstitial pneumonia should be included in the differential diagnosis of a diffuse pulmonary disease that is poorly responsive to medical treatment.

Trilateral retinoblastoma in transgenic mice

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Idiopathic cutaneous and renal glomerular vasculopathy of greyhounds

An idiopathic disease involving skin and occasionally kidneys was seen in kenneled and racing greyhounds. Hemorrhages, fibrinoid arteritis, thrombosis, and infarction with deep, slowly healing ulcers characterized the skin lesions. Peracute renal glomerular necrosis, particularly involving afferent arterioles with intravascular coagulation in glomerular capillaries were the distinctive findings in affected kidneys. A complex pathogenesis of this disorder was suspected in which genetic predisposition plays a prominent role.