PubMed Health⌕ Search

Biomedical subjects

S Feig

Publications and source records attributed to S Feig.

At least 19 recordsLinked to original sources
PubMed2001

Marrow transplants from unrelated donors for patients with aplastic anemia: minimum effective dose of total body irradiation.

Patients with aplastic anemia who do not have suitably HLA-matched, related donors generally receive immunosuppressive treatment as first-line therapy and are considered for transplantation from an unrelated donor only if they fail to respond to immunosuppressive treatment. In this setting, rates of transplantation-related morbidity and mortality have been high. We conducted a prospective study to determine the minimal dose of total body irradiation (TBI) sufficient to achieve sustained engraftment when it is used in combination with 3 cycles of 30 mg/kg of antithymocyte globulin (ATG) and 4 cycles of 50 mg/kg of cyclophosphamide (CY). We also wanted to determine the tolerability and toxicity of the regimen. The starting dosage of TBI was 3 x 200 cGy given over 2 days following CY/ATG. The TBI dose was to be escalated in increments of 200 cGy if graft failure occurred in the absence of prohibitive toxicity, and de-escalated for toxicity in the absence of graft failure. Twenty-one female and 29 male patients aged 1.3 to 46.5 years (median age, 14.4 years) underwent transplantation at 14 medical centers. The time interval from diagnosis to transplantation was 2.8 to 264 months (median, 14.5 months). All patients had been transfused multiple times and all had received 1 to 11 courses (median, 4 courses) of immunosuppressive treatment and other modalities of treatment. In 38 cases, the donors were HLA-A, -B and -DR phenotypically matched with the patients, and, in 12 cases, the donor phenotype differed from that of the recipient by 1 HLA antigen. Recipients of mismatched transplants were considered separately for TBI dose modification, and this study is still ongoing. Seven patients did not tolerate ATG and were prepared with 6 x 200 cGy of TBI plus 120 mg/kg of CY. Of the HLA-matched recipients prepared with CY/ATG/TBI, all 20 who received 3 x 200 or 2 x 200 cGy of TBI achieved engraftment, and 10 are alive. Of the 13 patients who received 1 x 200 cGy of TBI, 1 failed to engraft, and 8 are alive. Each of 10 patients who received an HLA-nonidentical transplant achieved engraftment, and 3 of 6 who were given 3 x 200 cGy of TBI, and 4 of 4 who were given 2 x 200 cGy are alive. Pulmonary toxicity occurred in 8 of 30 patients who were given 3 x 200 or 2 x 200 cGy of TBI concurrently with ATG and CY at 200 mg/kg, and in 2 of 13 patients who received 1 x 200 cGy of TBI, a pattern that suggests a decrease in toxicity with TBI dose de-escalation. Overall, the highest probability of survival (73%) was observed among patients who underwent transplantation within 1 year of diagnosis, compared with patients who underwent transplantation after a longer period of disease. In addition, younger patients (aged < or = 20 years) were more likely to survive than older patients (aged > 20 years). Thus, for patients with an HLA-matched, unrelated donor, a TBI dose of 200 cGy (in combination with CY/ATG) was sufficient to allow for engraftment without inducing prohibitive toxicity. As in previous studies, patient age and pretransplantation disease duration remain important prognostic factors.

Adolescent↗
PubMed1998

Corticocortical communication via the thalamus: ultrastructural studies of corticothalamic projections from area 17 to the lateral posterior nucleus of the cat and inferior pulvinar nucleus of the owl monkey.

Electron microscopic anterograde autoradiography has been used to analyze the morphology and postsynaptic relationships of area 17 cortical terminals in the lateral division of the lateral posterior nucleus (LPl) of the cat and medial division of the inferior pulvinar nucleus (IPm) of the owl monkey. Such terminals are thought to arise exclusively from layer 5 in the cat and primate (Lund et al. [1975] J. Comp. Neurol. 164:287-304; Abramson and Chalupa [1985] Neuroscience 15:81-95). All labeled terminals in both nuclei exhibited the morphology of ascending "lemniscal" afferents. That is, they contained round vesicles, were large, made asymmetrical synaptic and filamentous nonsynaptic contacts, and were classified as RLs. These cortical RLs also exhibited the postsynaptic relationships of lemniscal afferents. Thus, they were presynaptic to large dendrites within glial encapsulated glomeruli, where a majority was involved in complex synaptic arrangements called triads. They also were found adjacent to terminal profiles with pleomorphic vesicles but never adjacent to small terminals containing round vesicles. Our results suggest that the layer 5 projection from area 17 provides a functional "drive" for some LPl and IPm neurons. Information carried over this "re-entrant" pathway (Guillery [1995] J. Anat. 187:583-592) could be modified within the LPl and IPm by both cortical and subcortical pathways and subsequently conveyed to higher visual cortical areas, where it could be integrated with messages carried through the well-documented corticocortical pathways (Casagrande and Kaas [1994] Cerebral cortex New York: Plenum Press).

Animals↗
PubMed1998

Double-alkylator non-total-body irradiation regimen with autologous hematopoietic stem-cell transplantation in pediatric solid tumors.

PURPOSE: To determine the maximum-tolerated dose (MTD) of cyclophosphamide (CTX) when administered with fixed doses of carboplatin, etoposide, and melphalan (CEM) followed by autologous hematopoietic stem-cell transplantation (HSCT) in children with recurrent or high-risk solid tumors as a consolidation chemotherapy, and to make preliminary observations on efficacy. PATIENTS AND METHODS: Twenty-seven patients with solid tumors between the ages of 2 and 21 years were enrolled. Twenty of 27 had recurrent disease, whereas seven were treated in first remission. Nine were treated with melphalan 50 mg/m2/d for 4 days, carboplatin 300 mg/m2/d for 4 days as a continuous infusion (CI), and etoposide 200 mg/m2/d for 4 days as a CI (level I). CTX 750 mg/m2/d for 4 days was added to this regimen for the next 18 patients (level II). Seven of nine patients at level I and four of 18 at level II received bone marrow (BM) only, while two of nine at level I and 14 of 18 at level II received BM plus peripheral-blood stem cells (PBSC). RESULTS: The median time to reach an absolute neutrophil count (ANC) greater than 500/microl was 12.5 and 10 days for patients who received BM only and BM plus PBSC, respectively. Three cases of grade 3 mucositis, one Candida sepsis, and two transient hypoxemias were the main nonfatal toxicities. No toxic mortality was observed among level I patients. Three of 18 (16%) level II patients, all in second CR, died of transplant-related complications. Median follow-up is 29 months. Nine died of progressive disease (one second malignancy), six relapsed and are alive with disease, and nine are in continuous CR. Among the 15 PNET/Ewing's sarcoma patients, seven are in continuous CR (three of nine in second CR/VGPR, four of six in first CR/VGPR). CONCLUSION: The addition of CTX 3 g/m2 to CEM followed by autologous HSCT as a consolidation therapy resulted in 16% toxic mortality in children with recurrent or high-risk solid tumors. Further CTX dose escalation was aborted. No common nonhematologic toxicity was identified. The event-free survival (EFS) of 66% +/- 19% at 3 years for patients with metastatic PNET/Ewing's sarcoma in first remission is encouraging. However, this is based on only six patients. Both level I and II need further exploration in high-risk pediatric solid tumors in first remission.

Adolescent↗
PubMed1997

Cortical somatosensory and trigeminal inputs to the cat superior colliculus: light and electron microscopic analyses.

Two different axonal transport tracers were used in single animals to test the hypothesis that the expansive intermediate gray layer of the cat superior colliculus (stratum griseum intermediale, SGI) is composed of sensorimotor domains. The results show that two sensory pathways, the trigeminotectal and the corticotectal arising from the fourth somatosensory area, commingle in patches across the middle tier of the SGI. Furthermore, the data reveal that tectospinal cells are distributed within these patches. Taken together, these results show a commingling of functionally related afferents and a consistent spatial relationship between these afferents and tectospinal neurons. These relationships indicate that the SGI consists of domains that can be distinguished by their unique combinations of afferent and efferent connections. The ultrastructural characteristics and synaptic relationships of these somatosensory afferent pathways suggest that they have distinct roles within the sensorimotor domain of the SGI. The trigeminotectal terminals are relatively small, contain round vesicles and make asymmetrical synapses on small, presumably distal, dendrites. We submit that these trigeminal terminals bestow the basic receptive field properties upon SGI neurons. In contrast, the somatosensory corticotectal terminals are relatively large, contain round vesicles, make asymmetrical synapses, participate in triads, and are presynaptic to proximal dendrites. We suggest that these cortical terminals bestow integrative abilities on SGI neurons.

Afferent Pathways↗
PubMed1997

The impact of T-cell depletion on the effects of HLA DR beta 1 and DQ beta allele matching in HLA serologically identical unrelated donor bone marrow transplantation.

Unrelated donor bone marrow transplants have been associated with relatively high rates of acute graft-vs.-host disease and treatment-related mortality. These complications reflect histo-incompatibility between donor and recipient. Molecular technology has recently been applied to HLA typing to identify alleles not distinguishable with serologic typing techniques. We report results in 92 unrelated marrow transplant recipients who were HLA seroidentical with donor HLA-A, -B, and -DR antigens and assess the effect of DR beta 1 and DQ beta compatibility using sequence specific oligonucleotide primers. Forty-eight patients received T-cell depleted marrow grafts, and 44 received unmodified grafts. Among recipients of unmodified marrow grafts, matching for both DR beta 1 and DQ beta reduced the rate of grade 3-4 acute graft-vs.-host disease to 38 +/- 20% vs. 73 +/- 20% among recipients mismatched for either allele (p = 0.02). This difference was not observed in recipients of T-cell depleted marrow grafts. Multivariate analysis confirmed matching for both DR beta 1 and DQ beta loci (p = 0.015), and receiving a T-cell depleted graft (p = 0.008) independently predicted for reduced risk of grade 3-4 acute graft-vs.-host disease. In conclusion, both DR beta 1 and DQ beta appear biologically important for development of acute graft-vs.-host disease in patients receiving unmanipulated marrow grafts for unrelated donor transplant.

Adult↗
PubMed1996

Percutaneous core biopsy of the breast: effect of operator experience and number of samples on diagnostic accuracy.

OBJECTIVE: The purpose of our study was to assess the degree of operator experience and the number of core biopsy samples required to achieve an accurate histologic diagnosis for each of five common mammographically defined lesions, using percutaneous core breast biopsy performed on a dedicated prone biopsy table. SUBJECTS AND METHODS: A prospective multisite study was performed that involved nine institutions (academic and private) with experienced breast radiologists and the use of dedicated prone biopsy table units with digital assistance and standardized protocol. Asymptomatic women evaluated during a 2-year study period were assigned a mammographic diagnosis reported in a manner prescribed by the American College of Radiology Breast Imaging Reporting and Data System lexicon. Mammographic lesions evaluated included masses, masses with calcifications, clustered calcifications, focal asymmetries, and architectural distortions. Where histologic diagnosis was indicated, core biopsy was performed with five individual samples obtained and sequentially analyzed. Two hundred thirty patients had immediate excisional biopsy, the results of which provided the basis for a statistical analysis to compare the accuracy of each sequential core biopsy sample with surgical results. Statistical analysis was also done to ascertain the accuracy of core biopsy diagnosis as a function of operator experience. RESULTS: Trends toward increasing accuracy were observed by increasing the number of core biopsies for each of five types of mammographically defined lesions, especially for clustered calcifications. Statistically significant increased accuracy was observed when the number of biopsies was increased beyond one (p = .003). Trends toward increased accuracy with more experience were observed for all lesions, especially for calcifications. Of the 230 lesions studied with immediate surgical validation, more than 80% of all lesions except clustered calcifications (75%) were diagnosed on the basis of two core biopsies; accuracy after five biopsies was 98% for masses, 91% for calcifications, 100% for masses with calcification, 100% for focal asymmetries, and 86% for architectural distortions. CONCLUSIONS: Accuracy of diagnosis based on the results of percutaneous core breast biopsy improved with an increase in the number of core biopsy samples obtained for any given lesion seen on mammograms and with increased experience in performing the procedure. Five samples yielded an overall diagnostic accuracy of 97%. Familiarity with expected accuracy from this procedure for different mammographic lesions and following increased experience may assist physicians in planning patient management.

Analysis of Variance↗
PubMed1994

Ultrastructural studies of the primate lateral geniculate nucleus: morphology and spatial relationships of axon terminals arising from the retina, visual cortex (area 17), superior colliculus, parabigeminal nucleus, and pretectum of Galago crassicaudatus.

The electron microscopic autoradiographic tracing method has been used to examine the morphology and postsynaptic relationships of five projections (retina, cortical area 17, superior colliculus (tectal), parabigeminal nucleus, and pretectum) to the dorsal lateral geniculate nucleus of the greater bush baby Galago crassicaudatus. Retinal terminals have been examined in the contralaterally innervated layer of each of the three matched pairs [parvi- (X-cell), magno- (Y-cell), and koniocellular (small, W-cell)] of geniculate layers. These terminals are large and contain pale mitochondria and round vesicles (RLPs). RLPs are presynaptic to juxtasomatic regions of parvi- and magnocellular neurons. In contrast, RLPs innervate more distal regions of koniocellular neurons. Labeled cortical, tectal, and parabigeminal terminals are relatively small and contain round vesicles and dark mitochondria. Cortical terminals in each of the three representative layers are presynaptic to small diameter dendrites. No convergence of cortical and retinal terminals has been seen in any layer. Labeled tectal and parabigeminal terminals are found primarily in the koniocellular layers, but the latter are also seen in all other layers. Tectal and parabigeminal terminals have been observed converging with retinal terminals on dendrites of some koniocellular neurons. Labeled pretectogeniculate terminals contain densely packed pleomorphic vesicles, dark mitochondria, and a dark cytoplasmic matrix. These terminals, which are present in each of the representative layers, are presynaptic to conventional dendrites and profiles containing loosely dispersed pleomorphic vesicles and a pale cytoplasmic matrix.

Animals↗
PubMed1994

Selective depletion of CD8+ cells for prevention of graft-versus-host disease after bone marrow transplantation. A randomized controlled trial.

We performed a prospective randomized, double-blind study to assess the efficacy of selective depletion of CD8+ bone marrow cells in preventing acute graft-versus-host disease (GVHD) in 38 patients undergoing HLA-identical sibling donor bone marrow transplantation for leukemia. All patients received CsA for GVHD prophylaxis. Nineteen patients received marrow depleted of CD8+ cells by ex vivo treatment with anti-leu2, an anti-CD8 mAb and complement; four patients had moderate (grade 1 or 2 acute GVHD) and the only patient who experienced grade 3 manifestations was a technical failure. The control group consisted of 19 patients who received unmodified bone marrow; one patient had grade 1, 4 patients had grade 2, and 10 had grade 3 or 4 acute GVHD. The actuarial incidence of grade > or = 2 acute GVHD was 20 +/- 20% in the CD8-depleted group compared with 80 +/- 18% in the controls (P = 0.004). Death in 5 of the control patients and the single patient in whom CD8 depletion was a technical failure was related to acute GVHD. Graft failure occurred in 2 patients in the CD8-depleted group and in none of the controls. Leukemic relapse occurred in 2 patients receiving CD8-depleted bone marrow and 2 patients in the control group. Seven patients receiving marrow depleted of CD8+ cells are alive and free of leukemia and 9 patients in the control group are alive, 7 of whom remain leukemia-free (P = 0.88). The 3-year actuarial leukemia-free survival is 37 +/- 22% of the CD8-depleted group and 36 +/- 22% for the control group. These results indicate that selective depletion of CD8+ cells from the bone marrow significantly reduces the incidence and severity of acute GVHD.

Adolescent↗
PubMed1994

Treatment of newly diagnosed children and adolescents with acute myeloid leukemia: a Childrens Cancer Group study.

PURPOSE: The objectives of this study were to determine if the addition of etoposide, thioguanine, and dexamethasone to daunorubicin and cytarabine (five-drug regimen) during induction would improve remission induction rates and survival of children with acute myeloid leukemia (AML) when compared with the standard regimen of cytarabine and daunorubicin (7 + 3) and whether allogeneic bone marrow transplantation (BMT) or intensive chemotherapy consolidation with or without maintenance would give a superior outcome. PATIENTS AND METHODS: A total of 591 assessable children with AML entered Childrens Cancer Group (CCG) trial 213 between January 1986 and February 1989. The status of patients as of September 1, 1992 forms the basis of this report. The results were compared with previous AML studies. RESULTS: The projected survival rate of all patients at 5 years is 39% (event-free survival [EFS] rate, 31%), which is superior to that of the prior CCG study (P = .01). The induction rate was 79% for 7 + 3 and 76% for the five-drug regimen (not significant). Comparisons of BMT to chemotherapy favored BMT, but these differences do not always reach statistical significance (eg, 5-year disease-free survival [DFS] rate, 46% v 38% [P = .06] with donor available and 54% v 37% [P = .002] if treated according to protocol intent). No benefit for maintenance therapy was found and, in some comparisons, it was inferior to discontinuation of therapy (5-year survival rate, 46% v 68%, P < .01). CONCLUSION: The 5-year EFS rate of patients with AML is 31% and has improved. The five-drug induction regimen is no better than standard induction, BMT appears superior to chemotherapy, and maintenance therapy was not beneficial.

Adolescent↗
PubMed1993

Pairing the cholinergic agonist carbachol with patterned Schaffer collateral stimulation initiates protein synthesis in hippocampal CA1 pyramidal cell dendrites via a muscarinic, NMDA-dependent mechanism.

Effects of afferent stimulation on local synthesis of protein in CA1 pyramidal cell dendrites were studied using light microscope autoradiography. Tissue was fixed with paraformaldehyde immediately after 3 min exposure to 3H-leucine in order to trap 3H associated with macromolecules. The rate of 3H-leucine incorporation into dendrites of resting hippocampal slices was 10% the rate of incorporation into cell somata. Ninety percent of the incorporation into the somata was inhibited by cycloheximide (300 microM); none of the incorporation into dendrites was blocked by cycloheximide. Thus, there is no measurable extramitochondrial synthesis of protein in the dendrites of the resting slice. Slices were exposed to 50 microM carbachol and the Schaffer collateral afferents to the CA1 pyramidal cells were stimulated intermittently at 10 Hz over a 20 min period. In this case, 3H incorporation into dendrites was increased almost threefold over resting levels, with no effect on label over the cell somata. There was no associated increase in uptake of free 3H-leucine, and the increase in label was completely blocked by cycloheximide. Thus, associating carbachol and afferent stimulation appears to activate de novo protein synthesis in the dendrites. Neither the carbachol alone nor the Schaffer collateral stimulation alone increased synthesis. The activation of dendrite synthesis was completely blocked by 5 microM atropine, and also by 50 microM D-aminophosphonovalerate. It did not occur when carbachol was paired with steady stimulation of the Schaffer collaterals at 1 Hz for 20 min, rather than with the patterned high-frequency stimulation. Thus, associating a cholinergic agonist with a level of neural activity that occurs in CA3 and CA1 pyramidal cells during exploratory behavior (Muller et al., 1987) initiates local protein synthesis in target dendrites. This effect is dependent on muscarinic cholinergic receptors and NMDA-type glutamate receptors. The possible relationship of this phenomenon to mechanisms of learning is discussed.

2-Amino-5-phosphonovalerate↗
PubMed1992

Ultrastructural studies of the primate parabigeminal nucleus: electron microscopic autoradiographic analysis of the tectoparabigeminal projection in Galago crassicaudatus.

The normal ultrastructure of the parabigeminal nucleus and the morphology and synaptic relationships of tectoparabigeminal terminals have been examined. Five different morphological types of terminals have been observed within the parabigeminal nucleus. Three of these profiles contain round vesicles and make asymmetrical synapses, while two contain pleomorphic vesicles and make symmetrical synapses. Electron microscopic autoradiographic data indicate that labeled tectoparabigeminal terminals represent only one of the three profiles containing round vesicles. Such terminals are primarily presynaptic to dendritic shafts, and several labeled profiles have been observed presynaptic to the same dendrite.

Animals↗
PubMed1992

Ultrastructural studies of retinal, visual cortical (area 17), and parabigeminal terminals within the superior colliculus of Galago crassicaudatus.

The morphology and synaptic relationships of anterogradely labeled retinal, visual cortical (area 17), and parabigeminal terminals have been analyzed within the superficial gray (stratum griseum superficiale) of Galago crassicaudatus. Our data regarding the retinocollicular projection reveal two populations of terminals based upon size. The population of smaller terminals are found in clusters, while the larger occur in isolation. Both populations of retinocollicular terminals form synapses primarily with dendritic spines, but synapses upon pale vesicle filled (PVF) profiles and dendritic shafts also occur. Corticotectal terminals contain round vesicles and make asymmetrical synapses, primarily onto dendritic spines; few form synapses with PVF profiles. Our findings suggest the possibility that there are two populations of corticotectal terminals based upon differences in size and morphology. Parabigeminotectal profiles contain densely packed round vesicles and make asymmetrical synapses. These terminals, which are exclusively cholinergic in Galago, are presynaptic to dendrites of various sizes. Convergence of retinal and cortical terminals has been observed. This convergence occurs on distinctly separate regions of the postsynaptic membrane. In contrast, convergence of retinal and parabigeminal terminals occurs on the same region of the postsynaptic cell(s).

Afferent Pathways↗
PubMed1991

Connectional studies of the primate lateral geniculate nucleus: distribution of axons arising from the thalamic reticular nucleus of Galago crassicaudatus.

Anterograde and retrograde transport methods have been used to explore the interconnections between the thalamic reticular nucleus (TRN) and the dorsal lateral geniculate nucleus of Galago crassicaudatus. We first defined the region of the TRN, which is connected to the lateral geniculate nucleus, by examining the distribution of geniculo-TRN axons, cortico-TRN axons arising from area 17, and the location of TRN-geniculate neurons. Following an intraocular injection of 3H-proline/3 H-leucine, trans-synaptically transported protein is present bilaterally within the lateral portion of the caudal TRN. This same caudal and lateral region is also targeted by cortico-TRN axons and contains neurons which project upon the lateral geniculate nucleus. Light microscopic anterograde transport methods were used to analyze the distribution of TRN-geniculate axons. Our data reveal that all layers and interlaminar zones of the dorsal lateral geniculate nucleus contain TRN axons. Electron microscopic-autoradiographic data support and extend our light microscopic findings by revealing labeled TRN terminals within all geniculate layers. These TRN profiles are the same size throughout the geniculate and exhibit morphological characteristics similar to F1 terminals described by others. That is, they possess predominantly pleomorphic vesicles, a dark cytoplasmic matrix, dark mitochondria, and symmetrical synaptic contacts. Two additional features of TRN terminals have been observed in some profiles. These include dense-core vesicles and a dense, punctate cytoplasmic matrix, which is sometimes associated with the postsynaptic specialization. In addition to their morphology and size, the postsynaptic targets of TRN terminals are similar within the three sets (parvi-, magno-, and koniocellular) of geniculate layers. TRN profiles terminate upon dendrites of all sizes and somata. These findings suggest that the TRN modulates the retino-geniculocortical pathway and that this modulation is occurring in all three streams.

Animals↗
PubMed1990

Selective depletion of CD8+ T lymphocytes for prevention of graft-versus-host disease after allogeneic bone marrow transplantation.

The effects of selectively depleting CD8+ cells from donor bone marrow were assessed in 36 patients receiving transplantation from an HLA-identical sibling as treatment for leukemia. Donor bone marrow underwent ex vivo treatment using anti-Leu-2 monoclonal antibody and complement. Patients received cyclosporine post-transplant for 6 months. Thirty-three patients had initial engraftment. Three failed to have hematologic recovery, and one patient with initial engraftment had late graft failure. The actuarial incidence of grade greater than or equal to 2 acute graft-versus-host disease was 28% +/- 18% and was usually confined to the skin. Of 33 patients with engraftment, 32 were complete chimeras and one had mixed chimerism. The tempo of hematologic and immunologic recovery was comparable with that reported with transplantation of unmodified bone marrow, although CD4+ and CD8+ T cells recovered at comparable rates. The actuarial rate of leukemia relapse was 11% +/- 10%, occurring in three patients with acute leukemia but in none of 13 patients transplanted for chronic myelogenous leukemia. Actuarial survival was 57% +/- 17% at 2 years. These data indicate that after transplantation of marrow depleted of CD8+ cells, engraftment with prompt hematologic and immunologic recovery generally occurs, with a relatively low rate of acute graft-versus-host disease. Graft failure remains a problem despite retention of CD4+ cells within the donor marrow. The lack of leukemia relapse in patients with chronic myelogenous leukemia suggests retention of a graft-versus-leukemia effect, at least for this malignancy.

Adolescent↗
PubMed1990

Ninety-five percent splenectomy for massive splenomegaly: a new surgical approach.

Subtotal splenectomy for children with Gaucher's disease has been a major contribution. When spleens of massive size are mobilized for partial resection, it may be technically difficult to remove more than 80% to 85% and still maintain hilar blood supply. The short gastric vessels are enlarged in patients who have marked splenomegaly and provide sufficient vascularity to support the 5% of remaining spleen that is desired in these patients. When the upper pole of the spleen is retained, as in the present case, the cut surface is relatively small and hemostasis is technically easier to achieve than when resection is performed closer to the center of the spleen.

Child, Preschool↗
PubMed1990

N-methyl-D-aspartate receptor activation and Ca2+ account for poor pyramidal cell structure in hippocampal slices.

The CA1 pyramidal cells appear damaged in micrographs of guinea pig hippocampal slices incubated in normal physiological buffer at 36-37 degrees C. This is remedied if slices are incubated in modified buffers for the first 45 min. Cell morphology is improved if this buffer is devoid of added Ca2+ and much improved if it contains N-methyl-D-aspartate (NMDA) receptor antagonists or 0 mM Ca2+ and 10 mM Mg2+. The cells then appear similar to CA1 pyramidal cells in situ. These findings support the notion that NMDA receptor activation and Ca2+, acting in the period immediately after slice preparation, permanently damage CA1 pyramidal cells in vitro.

Adenosine Triphosphate↗
PubMed1988

Use of fine needle aspiration cytology for the diagnosis of testicular relapse in patients with acute lymphoblastic leukemia.

The testis frequently is the site of relapse in male patients with acute lymphoblastic leukemia. While many patients with testicular involvement by acute lymphoblastic leukemia have enlarged or firm testes, clinical examination alone is insufficient to establish or exclude the diagnosis completely. Open biopsy generally has been used to document the presence of acute lymphoblastic leukemia. However, this procedure requires general anesthesia and hospitalization. We studied 11 patients with a history and/or physical findings suspicious for testicular acute lymphoblastic leukemia relapse to determine the efficacy of fine needle aspiration cytology in the evaluation of the testes for leukemic infiltration. Of the 11 patients fine needle aspiration cytology correctly identified all 5 patients with histologically proved testicular acute lymphoblastic leukemia, it was negative in 5 with no histological evidence of leukemia and it demonstrated rare atypical cells that were not evident on subsequent histological examination in 1. No adverse effects were encountered in this series. Fine needle aspiration cytology appears to be a safe, reproducible alternative to open biopsy in the evaluation of patients for testicular relapse of acute lymphoblastic leukemia.

Adolescent↗