Deterioration of word meaning: implications for reading

We investigated six patients with progressive focal dementia or progressive aphasia, who showed impairments in knowledge of word meaning ranging from moderate to very severe. In all cases, a test of oral word reading demonstrated preserved reading of words with regular spelling-to-sound correspondences (e.g. MINT), but impaired reading of words with atypical correspondences (e.g. PINT). The level of success on these "exception" words was significantly related to word frequency, and the most common error was the assignment of a more typical spelling-sound correspondence. Various explanations are considered for this common association between loss of word meaning and a surface alexic pattern of reading performance.

Regional response differences within the human auditory cortex when listening to words

The relationship between activity within the human auditory cortices and the presentation rate of heard words was investigated by measuring changes in regional cerebral blood flow with positron emission tomography. We demonstrate that in the primary auditory cortices and middle regions of the superior temporal gyri there is a linear relationship between the rate of presentation of heard words and blood flow response. In contrast, the blood flow response in an area of the left posterior superior temporal gyrus (Wernicke's area) is primarily dependent on the occurrence of words irrespective of their rate of presentation. The primary auditory cortices are associated with the early processing of complex acoustic signals whereas Wernicke's area is associated with the comprehension of heard words. This study demonstrates for the first time that time dependent sensory signals (heard words) detected in the primary auditory cortices are transformed into a time invariant output which is channelled to a functionally specialised region--Wernicke's area. Wernicke's area is therefore distinguished from other areas of the auditory cortex by direct observation of signal transformation rather than by association with a specific behavioural task.

Solitary thyroid nodules in 71 children and adolescents

Seventy-one children and adolescents with a solitary nodule of the thyroid gland were seen over a 27-year period and all had their nodules removed surgically. All of the patients had preoperative thyroid scintiscans, 55 of which showed a cold nodule. The most common cause of solitary thyroid nodules was follicular adenoma. Fourteen of the 55 cold nodules were malignant (25.5%) while no malignancies were present in warm or hot nodules. Available diagnostic methods for attempting differentiation of benign from malignant solitary nodules are reviewed and recommendations to their clinical management as derived from our experience are presented.

Gaucher disease: abdominal MR imaging findings in 46 patients

Abdominal magnetic resonance imaging findings were reviewed in 46 patients with Gaucher disease. All patients had hepatosplenomegaly at the time of initial imaging. Splenic nodules were present in 14 patients (30%) and varied in signal intensity. These nodules were isointense on T1-weighted and hypointense on T2-weighted images. Splenic infarcts were seen in 15 patients (33%), and four of these patients (9%) also had subcapsular fluid collections. Both nodules and infarcts were present in the spleen in four patients (9%). Pathologic correlation was performed with specimens from two patients who underwent partial splenectomy. Focal areas of abnormal signal intensity were noted in the liver in nine patients (20%). They were either stellate or segmental, and may represent fibrotic septa with ischemic changes associated with aggregates of Gaucher cells. No changes were noted in the kidneys or abdominal lymph nodes.

Primary nasal chondrosarcoma. The pediatric experience

Chondrosarcomas are infrequently found in the head and neck region. In a review of nonepithelial tumors of the nasal cavity, paranasal sinuses, and nasopharynx, only 4% were chondrosarcomas. The peak incidence occurs in the fourth decade of life. Only four cases of head or neck chondrosarcoma in children less than or equal to 10 years of age have been described in the literature, and only two of these were primary nasal cavity tumors. We present in this report a case of a 5-year-old boy treated with adjuvant chemotherapy after complete resection of a nasal cavity chondrosarcoma, and a review of the literature on this topic.

Effects of temafloxacin and ciprofloxacin on the pharmacokinetics of caffeine

A number of quinolone antibacterial agents, particularly enoxacin, pefloxacin, pipemidic acid and ciprofloxacin, are known to decrease the clearance of methylxanthines. The effects of temafloxacin and ciprofloxacin on the pharmacokinetics of caffeine were therefore compared in a 3-way crossover study in 12 healthy young volunteers. Each volunteer received 183mg once-daily doses of caffeine in conjunction with twice-daily placebo, temafloxacin 600mg and ciprofloxacin 750mg in 3 separate phases according to a randomised sequence. A doubling of the area under the plasma concentration-time curve (77.8 vs 31.8 mg/L.h) and terminal-phase half-life (9.7 vs 4.5h) of caffeine were observed in the presence of ciprofloxacin. The magnitude of the reduction in the intrinsic clearance of caffeine produced by ciprofloxacin was greater than that described in the literature for ciprofloxacin and theophylline. This may partly be explained by intertrial differences in dosage and study design. Coadministration of temafloxacin did not have any effect on the pharmacokinetics of caffeine, confirming results of other studies suggesting that this agent does not affect methylxanthine clearance. Accordingly, it appears that restriction of caffeine intake during temafloxacin therapy is not necessary.

Impact of two cycles of preoperative chemotherapy with intraarterial cisplatin and intravenous doxorubicin on the choice of surgical procedure for high-grade bone sarcomas of the extremities

The authors assessed the impact of two cycles of preoperative chemotherapy (POCT) with intraarterial cisplatin (120 mg/m2) and continuous intravenous doxorubicin hydrochloride (Adriamycin; 20 mg/m2/day x 3 days) on the decision to perform a limb-sparing procedure (LSP) or amputation in 22 patients with high-grade bone sarcomas of the extremities. The tumor types were osteosarcoma (17), malignant fibrous histiocytoma (three), leiomyosarcoma (one), and malignant schwannoma (one). Surgical stages were IIA (three), IIB (17), and IIIB (two). The prechemotherapy surgical options chosen were 12 amputations (55% of patients) and ten LSPs (45%). The initial decisions to amputate were based on a combination of the following: improper biopsy (five cases), large tumors (ten) and those with neurovascular encroachment (six), and pathological fracture (one). Following chemotherapy, 18 LSPs (81%) and four amputations (19%) were performed. Nine of 12 patients (75%) initially deemed unresectable were converted to LSP. The median tumor response (necrosis; range, 0%-100%) was 70%; ten of 22 specimens had necrosis greater than 95%. Median tumor necrosis for the patients treated by amputation and LSPs was 45% and 88%, respectively. Following surgery, all patients received four additional cycles of cisplatin and doxorubicin. The median follow-up period is 30 months; six patients have developed metastatic disease, with a median disease-free interval of 16.6 months. The rate of local tumor control is 95% (21 of 22 patients).(ABSTRACT TRUNCATED AT 250 WORDS)

A survey of antiemetic use in children with cancer

Pediatric oncologists within Pediatric Oncology Group institutions were surveyed to determine current antiemetic practices for children receiving chemotherapy and the basis for those practices. A mean severity rating for associated nausea and vomiting was calculated and used to rank 31 chemotherapeutic agents commonly used in the treatment of childhood cancer. Antiemetics were used 17%, 79%, and 98% of the time for chemotherapeutic agents with mild, moderate, or severe associated nausea and vomiting, respectively. A median of one, two, and three antiemetics were used for mild, moderate, and severe agents, respectively. Antihistamines and phenothiazines were the drugs most commonly used for agents causing mild or moderate nausea and vomiting, and metoclopramide hydrochloride/antihistamines with lorazepam and/or corticosteroids were used most often for chemotherapeutic agents causing severe nausea and vomiting. Most oncologists based their choice of antiemetics on personal experience. Current literature addressing the treatment of nausea and vomiting in children receiving chemotherapy, as reviewed here, does not always support the present clinical practices.

Pediatric renal artery dysplasia: a morphologic study

Renal arteries from 12 pediatric patients who had stenosis due to renal artery dysplasia (9 surgical resections and 3 autopsy cases) were examined by light microscopy. The patients ranged in age from 15 months to 14 years; the male/female ratio was one. Bilateral renal artery disease was clinically diagnosed in 8 of the 12 patients; 6 of the 8 also had aortic anomalies. All of the lesions were designated as forms of dysplasia, a departure from previous reports in which dysplasia was subclassified as fibroplasia and hyperplasia. The most common lesion was medial fibrous dysplasia (6), followed by perimedial elastic dysplasia (4); intimal fibrous dysplasia (1) and medial muscular dysplasia (1) were the least common. Medial fibrous dysplasia was present as often with bilateral as with unilateral renal artery stenosis, while perimedial elastic dysplasia was seen exclusively in patients with bilateral renal artery disease. Three patients who came to autopsy had extrarenal vascular involvement by a similar dysplastic lesion. The three patients who had neurofibromatosis showed no distinctive histologic type of renal artery dysplasia.

Morphometry of ampullar dark cells

The morphologic characteristics of rat ampullar dark cells were analyzed quantitatively. Four parameters were measured: cell area per micron baseline length, membrane surface density, volume density of intercellular space, and volume density of vacuoles. No statistically significant difference was observed for any parameter, either between dark cell regions of the superior, lateral, and posterior ampullae or between different regions of dark cells within a given ampulla. The membrane surface density of the ampullar dark cells was similar to that reported for principal cells of the cortical collecting duct in the kidney. The volume density of the intercellular spaces of the dark cells was very constant, unlike that reported for epithelia involved in isotonic fluid transport. Vacuoles were found to comprise only a small portion of protoplasm in the dark cells. This new morphometry provides a basis on which to examine the response of ampullar dark cells to differing experimental conditions.

Ultrastructure of ampullar dark cells in the absence of circulating adrenocorticosteroid hormones

The morphology of rat ampullar dark cells was studied in the absence of circulating adrenal hormones at two time intervals of 8-14 and 22-28 days. Five morphological parameters of dark cells were quantitatively determined: cell area per baseline length, basolateral membrane surface density, basolateral membrane length per baseline length, volume density of intercellular space and volume density of vacuoles. Significant statistical reduction of basolateral membrane length per baseline length was observed after an absence of circulating adrenal hormones for 8-14 days and 22-28 days compared to sham operated animals that served as control. The basolateral membrane surface density decreased significantly in the animals sacrificed 22-28 days following adrenalectomy compared to sham operated animals. Cell area per baseline length decreased and volume density of vacuoles increased at both time intervals following adrenalectomy; however, these differences were statistically insignificant. The volume density of intercellular space between dark cells was practically constant among the groups. Results of this study are similar to those reported for ion-regulating nephron cells, and support the hypothesis that cells involved in microhomeostasis of vestibular endolymph may at least be partly regulated by adrenal hormones.

Testicular sparing surgery for prepubertal teratoma of the testis: a clinical and pathological study

We report on 5 patients 14 months to 6 1/2 years old with prepubertal teratoma of the testis treated by testicular sparing tumor enucleation. All 5 patients had no evidence of recurrence at a mean followup of 96 months. Recognizing that this is not accepted therapy for testis tumors, 17 orchiectomy specimens containing teratoma from children were histologically analyzed in cooperation with the Armed Forces Institute of Pathology Tumor Registry. All patients were prepubertal at orchiectomy (3 months to 8 years old) and all are well with a mean followup of 174 months. Histological examination revealed no foci of teratoma separate from the main tumor in any specimens. Immunohistochemical studies with placental alkaline phosphatase, a marker for malignant germ cells, were done to detect carcinoma in situ in the seminiferous tubules of these testes. This test did not reveal any intratubular malignant germ cells (carcinoma in situ). Based on our clinical experience with testicular sparing tumor enucleation, the histological findings on Armed Forces Institute of Pathology review demonstrating no associated carcinoma in situ and the universally benign behavior of prepubertal testicular teratomas, we recommend a testicular sparing operation rather than orchiectomy for testicular teratoma in prepubertal patients.

Quantitative assessment of the rat stria vascularis

Stria vascularis tissues from standardized regions in the basal, middle and apical turns of the rat cochlear duct were assessed quantitatively. Strial width, number of marginal cells across the strial width, radial area, as well as the volume density of the different components of the stria vascularis were determined for each standardized region. Strial width, number of marginal cells across the strial width and the radial area were greatest in the basal region and least in the apical region of the cochlea. The volume density of intermediate cells and capillary space was statistically unchanged in the three examined regions of the stria vascularis. However, the volume density of marginal cells and that of basal cells were different between regions. The volume density of marginal cells was highest in the basal turn while the volume density of basal cells was greatest in the apical turn. An objective assessment of the response of the stria vascularis to environmental conditions can be made by kant of its cellular architecture, providing a means to compare the effects of various agents between animal models used to study human inner ear dysfunction.

Pulse oximetry as a means of assessing bowel viability

Utilizing a pulse oximeter, oxygen saturation was determined in the periphery (tongue) and compared to the intestinal wall in a canine model. Segmental intestinal ischemia was then produced and the last obtainable pulse oximetry reading was marked with a suture on either end of the ischemic segment. Reexploration was performed within 48 hr and full thickness biopsies were taken in normal intestine and at various distances into the ischemic segment. Blinded evaluation of the biopsies showed that all biopsies taken within 1 cm of a normal pulse oximetry reading were normal, whereas at 3 cm into the ischemic segment 7 of 15 biopsies showed partial necrosis and 5 of 15 showed full thickness necrosis. We conclude that pulse oximetry of the intestinal wall is a valuable method of assessing intestinal viability in this model.

Decreased adenosine triphosphatase activity in the absence of adrenocorticosteroids

Changes in adenosine triphosphatase activity and cellular integrity of rat inner-ear tissues were observed after removal of adrenal steroids via bilateral adrenalectomy. Statistical significance of total and magnesium ion-dependent adenosine triphosphatase activities of the stria vascularis, spiral ligament, and ampullar dark cells from adrenalectomized animals was detected when compared with those of controls as demonstrated by fluorometric microassay. Although there was a similar reduction of activity in utricular dark-cell tissues, no significant difference between the treated and control animals was observed. An increase of intercellular space and a decrease in basolateral infoldings of cells of the stria vascularis and dark cell regions of adrenalectomized animals were observed. Such data collectively provide indirect evidence that adrenal steroids are involved in the cellular regulation of inner-ear tissues that are concerned with fluid and ionic microhomeostasis.

Establishment of inner ear epithelial cell culture: isolation, growth and characterization

Select epithelial regions of the bovine inner ear were established and maintained in cell culture. Marginal cells from the stria vascularis and dark cells from the posterior wall of the utricle were isolated, dissociated and placed in culture medium. Within 24 h, cellular islands of hexagonal-shaped, epithelial-like cells from both the stria vascularis and posterior utricular wall were readily identifiable by inverted light microscopy. Ultrastructural examination of both the cultured stria marginal cells and utricular dark cells revealed that both cell types had numerous microvilli on their apical surfaces and interdigitating infoldings of their basolateral surfaces. Apical tight junctional complexes were present between apposing cells. These findings demonstrate that inner ear bovine epithelial cells can be successfully isolated and maintained in culture, and that such cells retain certain of their in vivo morphological characteristics.

Reading with one hemisphere

The subjects of this study were 2 originally right-handed teen-aged girls who had undergone complete hemispherectomy (1 left, 1 right) for intractable epilepsy. Both subjects had developed normal language and reading capacities before the onset of their illness. The reading performance of H.P. (whose right hemisphere had been removed), while not as advanced in level as that of a normal 17-yr-old, showed no abnormality in any subcomponent of reading skill. The reading performance of N.I. (whose left hemisphere had been removed) was poor, but with a pattern of retained and impaired subskills strikingly similar to adult deep dyslexic patients and to split-brain patients given reading tasks lateralized to the left visual field (right hemisphere). The results are discussed with regard to implications for the reading capacity of the nondominant right hemisphere and also its putative contribution to normal reading.

Endothelin-1 stimulates phosphatidylinositol hydrolysis and calcium uptake in isolated canine coronary arteries

The effects of synthetic endothelin-1 (ET-1) (10(-10)-3 x 10(-7) M) on isometric force, 45Ca2+ uptake, and phosphatidylinositol (PI) hydrolysis were determined in isolated canine coronary artery rings. ET-1 caused contraction and stimulated 45Ca2+ uptake and PI hydrolysis (determined as inositol monophosphate accumulation) in a concentration-dependent manner with EC50 values of 6.3 x 10(-9), 2 x 10(-9), and 3 x 10(-9) M, respectively. Maximal responses were obtained with 3 x 10(-8) M ET-1 for all three parameters. At the maximally effective concentration, ET-1 caused a 1.8-fold increase in the rate of 45Ca2+ uptake following a 1-min exposure (the shortest time point tested) while the contractile response reached maximum only after 6 min. ET-1 (3 x 10(-8) M) stimulated a biphasic accumulation of inositol monophosphate with an initial rapid 1.4-fold increase detectable between 30 and 60 s followed by a secondary 11.9-fold increase at 30 min. These data show that PI hydrolysis and Ca2+ uptake are early events in the action of ET-1 on coronary artery vascular smooth muscle that precede the maximal contractile response. It is suggested that all of these responses are triggered by the interaction of ET-1 with a cell-surface receptor.

GM-CSF accelerates neutrophil recovery after autologous bone marrow transplantation for Hodgkin's disease

Thirty-one patients with resistant Hodgkin's disease were treated by an identical high dose chemotherapy regimen and autologous bone marrow transplantation. Twelve of these patients received recombinant human granulocyte/macrophage colony stimulating factor (rh GM-CSF) in a phase I/II study. rh GM-CSF was administered by continuous infusion into an indwelling central venous catheter for 3-21 days at doses of 100-400 micrograms/m2/day. The patients receiving rh GM-CSF did not differ significantly from those who did not receive growth factor with regard to age, previous therapy or number of bone marrow cells infused. rh GM-CSF resulted in more rapid neutrophil regeneration, the average time to achieve a neutrophil count of greater than or equal to 0.5 x 10(9)/l being 17.5 days compared to 24.9 days in the control group (p less than 0.01). Platelet recovery was very varied and not accelerated by rh GM-CSF. Patients receiving rh GM-CSF had a similar infection rate (58% vs 68% in the control group), similar number of febrile days (5.0 vs 4.7 days) and similar period of hospitalization to the control group (30.1 vs 30.2 days). Randomized controlled trials are now required to define the clinical value of rh GM-CSF in the setting of autologous bone marrow transplantation.

Endobronchial eosinophilic granuloma: a rare cause of total lung atelectasis

A 12-yr-old male presented with left lung atelectasis secondary to a mainstem endobronchial mass. At thoracotomy, a left mainstem bronchial sleeve resection successfully extirpated what later proved to be an eosinophilic granuloma. This is the first case report, to our knowledge, of endobronchial eosinophilic granuloma.

Sexual differences in the expression of copper deficiency in rats

The present investigation was undertaken to establish whether the severity of copper deficiency in rats fed diets containing fructose is affected by the presence and type of endogenous sex hormones. Intact and castrated male rats and intact and ovariectomized females were fed from weaning a copper-deficient diet (0.6 ppm) containing 62% fructose for 8 weeks. Regardless of castration, male rats were anemic, exhibited heart hypertrophy, and died of the deficiency. However, castration ameliorated the anemia and delayed the mortality. In contrast, none of the females died of the deficiency. It is suggested that in addition to the sex of the animal, levels of testosterone in the male may also play a role in the severity of copper deficiency.