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Biomedical subjects

R Nuss

Publications and source records attributed to R Nuss.

52 records · Page 3Linked to original sources
PubMed1993

Cardiopulmonary function in men with sickle cell trait who reside at moderately high altitude.

Sickle cell trait has been associated with an unexplained increased risk of sudden death during military basic training. Previous studies of cardiopulmonary function in persons with sickle cell trait at sea level or after brief exposure to moderately high altitude have not shown significant abnormalities. To determine whether cardiopulmonary function is impaired in men with sickle cell trait who chronically reside at moderately high altitude, we prospectively studied 17 men with sickle cell trait and 25 men with normal hemoglobin. All subjects had resided at > or = 1609 m above sea level for at least 10 years. Resting pulmonary function and cardiopulmonary performance during exercise to exhaustion were evaluated. No statistically significant differences were observed between subjects with sickle cell trait and controls for any of the resting pulmonary function variables measured. All parameters of exercise performance were not statistically different between the groups. Increasing age was associated with a similar decrease in work capacity and oxygen consumption in both groups. Electrocardiogram findings were not statistically different between groups. We conclude that chronic exposure to moderately high altitude does not impair cardiopulmonary function in men with sickle cell trait.

Adult↗
PubMed1992

Effectiveness of continuous vs. intermittent amoxicillin to prevent episodes of otitis media.

The effectiveness of continuous compared with intermittent amoxicillin prophylaxis administered to subjects with a history of recurrent otitis media enrolled during the winter respiratory infection season was assessed in a prospective single blinded clinical trial. Patients with three or more chart-documented episodes of otitis media (OM) in the preceding 6 months were enrolled and randomly assigned to each treatment group. Patients in the continuous group received amoxicillin twice a day every day for up to 4 months. During the same period patients in the intermittent group received amoxicillin twice a day only when they developed respiratory symptoms of congestion, runny nose or cough. Among the 30 patients receiving continuous amoxicillin who were followed for at least 3 months, 22 (73%) had no OM episodes and 8 (28%) had one OM episode. Among the 25 patients receiving intermittent amoxicillin for at least 3 months, 13 (52%) had no OM episodes, 8 (32%) had 1 episode and 4 (16%) had 2 episodes. Significantly fewer patients had fewer than 2 OM episodes on continuous compared with intermittent amoxicillin (P less than 0.04). The incidence density was 0.46 episode/120 days at risk in the continuous treatment group compared with 1.10 episodes/120 days at risk for intermittent treatment (P less than 0.03). Among patients 12 months or older the incidence density of OM episodes per 120 days was 3.5 times higher in the intermittent amoxicillin group (0.80) compared with the continuous amoxicillin group (0.23) (P = 0.05). The incidence densities of the continuous vs. intermittent therapy groups did not differ significantly for patients younger than 12 months of age. The findings suggest that continuous amoxicillin prophylaxis may be more effective than intermittent treatment in preventing OM episodes in patients 12 months or older with a history of recurrent otitis media.

Amoxicillin↗
PubMed1991

Splenic function in persons with sickle cell trait at moderately high altitude.

We investigated the possibility that persons with sickle cell trait who reside chronically at moderately high altitude might develop impaired splenic reticuloendothelial function. Seventeen healthy young black men with sickle trait who had lived at greater than or equal to 1,609 m for greater than or equal to 10 years participated in the study along with 25 matched control subjects with normal hemoglobin. Splenic function was assessed by radionuclide liver-spleen scanning and by red cell pit counts. No evidence of impaired splenic function was found in the sickle trait group. The data suggest that long-term residence at moderately high altitude does not place persons with sickle cell trait at risk for splenic dysfunction.

Adolescent↗
PubMed1990

Management of chronic middle ear effusion with prednisone combined with trimethoprim-sulfamethoxazole.

Fifty-three patients were enrolled and evaluable in a randomized, double-blinded controlled clinical trial comparing prednisone for 7 days plus trimethoprim-sulfamethoxazole (TMP/SMZ) for 30 days vs. TMP/SMZ alone in treating chronic middle ear effusion (MEE). Clearing of the effusion in both ears or in one when only one was involved was called complete resolution; clearing in one of two affected ears was called partial resolution. The outcomes 2 weeks after initiation of therapy of 26 patients initially treated with prednisone plus TMP/SMZ were complete resolution in 20, partial resolution in three, and unchanged in three. The outcomes in 27 patients initially treated with TMP/SMZ alone were complete resolution in eight, partial resolution in three, unchanged in 13 and development of acute otitis media in three (P less than 0.01 for complete resolution). Two weeks after initiation of therapy, patients with a MEE that failed to clear were crossed over to the alternative regimen. Overall 29 of 41 patients (71%) who received oral prednisone plus TMP/SMZ initially or after the crossover had complete resolution of their middle ear effusion at 2 weeks after starting prednisone and TMP/SMZ. Five of 35 (14%) patients treated with prednisone plus TMP/SMZ and one of six (17%) patients treated with TMP/SMZ alone who had complete resolution at 4 weeks required subsequent referrals for tympanostomy tubes. A course of prednisone for 7 days plus TMP/SMZ for 30 days with monthly follow-up should be considered in children with MEE persisting beyond 6-8 weeks before referral for tympanostomy tube placement.

Chronic Disease↗
PubMed1988

Immunoblastic peripheral T-cell lymphoma confined to bone marrow in an infant presenting with aspergillosis.

A 16-month-old female infant presenting with pancytopenia and fever was found to have pulmonary aspergillosis and large-cell immunoblastic non-Hodgkin's lymphoma of peripheral post-thymic origin isolated to bone marrow. Extensive noninvasive evaluations failed to demonstrate the disease in other extramedullary sites. The malignant cells were large and polymorphous; lacked terminal transferase; expressed surface CD-2, CD-3, CD-8, and HLA-DR antigens, and showed rearrangements of the T-cell-receptor beta-chain gene. To our knowledge, this type of lymphoma in an infant has not been reported before. Furthermore, aspergillosis is a rare presenting feature in patients with lymphoproliferative disease. In our case, it may reflect an underlying immune deficiency associated with the transformation and proliferation of a suppressor T cell.

Aspergillosis↗
PubMed1988

T cell receptor gene rearrangements in B-precursor acute lymphoblastic leukemia correlate with age and the stage of B cell differentiation.

Children with ALL diagnosed at less than 2 years of age have a poor prognosis when compared with older children. In an effort to identify biologic features of ALL in children less than 2 that might explain this difference, we performed extensive immunophenotypic and molecular genetic analyses on a series of patients. For comparison purposes patients were divided into four groups: CALLA- (CD10-) infants less than 2 years of age at diagnosis (n = 10), CALLA- children greater than 2 years of age at diagnosis (n = 10), CALLA+ infants (less than 2 years, n = 21) and CALLA+ children (older than 2 years, n = 21). No immunophenotyping differences in CALLA- or CALLA+ subgroups were identified when cases less than 2 were compared with cases greater than 2 years of age at diagnosis. The most interesting results were in the CALLA- group where 94% of the samples expressed the B cell antigen CD19 but 27% co-expressed CD7. Double labeling experiments confirmed leukemic blast cells co-expressed CD19 and CD7. The double-labeled cells represent either leukemic conversion of a precursor cell which has not yet committed to B or T cell lineage or aberrant expression of these antigens. Molecular genetic studies demonstrated that all samples, regardless of the patients' age or immunophenotype, had rearrangement of the Ig heavy chain gene. The most striking molecular results were in CALLA- patients; in patients less than 2 at diagnosis neither the beta- nor the gamma-chain gene of the T cell receptor (TCR) was rearranged, whereas DNA from 5 of 10 patients over the age of 2 demonstrated beta- or gamma-chain TCR gene rearrangements. The percentage of CALLA+ cases under the age of 2 years with rearrangements in TCR genes is less than that found in CALLA+ cases over the age of 2 years. The finding of no TCR rearrangements in CALLA- ALL and a decreased number of gamma-TCR rearrangements in CALLA+ cases under the age of 2 suggest that age may affect TCR gene rearrangements in lymphoblasts. The molecular differences in TCR gene rearrangements do not appear to correlate with the response to therapy.

Aging↗
PubMed1988

Acute myeloid leukemia with T-lymphoid features: a distinct biologic and clinical entity.

We studied the clinical and biologic features of 10 cases of acute leukemia that met standard French-American-British (FAB) criteria for acute myeloid leukemia (AML) but in which the blast cells also expressed the T-cell-associated CD2 surface antigen. All cases had greater than 3% myeloperoxidase and Sudan black B-positive leukemic blasts, and blasts from seven cases contained Auer rods. Reactivity of the cells with a panel of monoclonal antibodies (MAbs) indicated that leukemic cells in all cases expressed myeloid-associated (CD11b, CD13) surface antigens, further supporting the diagnosis of AML. However, blasts from every patient coexpressed the T-cell-associated surface CD2 and CD7 as well as cytoplasmic CD3 antigens. Blasts from five patients expressed surface CD25, whereas blasts from only one expressed surface CD3. Five patients had rearranged T-cell receptor beta-chain genes, whereas only three had rearranged T-cell receptor gamma-chain genes. This pattern of lineage-related gene expression appears to define a distinct subtype of AML with T-lymphoid features (CD2+ AML) and could reflect either aberrant gene expression in leukemic blasts or transformation of a pluripotent stem cell having a flexible pattern of gene expression. Clinically, these 10 patients presented at an older age with a higher leukocyte count and a higher frequency of lymphadenopathy than did children whose blast cells were characteristic of myeloid leukemia. Patients with CD2+ AML also had poorer responses to remission induction therapy (50% v 80% entered complete remission, P = .05). However, each of the five children who failed induction chemotherapy on AML protocols had a striking response to drug combinations usually reserved for lymphoid leukemia. We conclude that this leukemia with mixed lymphoid and myeloid characteristics is a distinct biologic and clinical entity.

Adolescent↗
PubMed1987

Intravenous gamma globulin for thrombocytopenia in children with Evans syndrome.

We describe three patients with Evans syndrome (immune hemolytic anemia and immune thrombocytopenia) who were refractory to conventional therapy, including steroids and splenectomy in all of the patients, vincristine in two, and cyclophosphamide in one. The patients were then treated with modified intravenous gamma globulin 0.4 g/kg/day for 5 consecutive days. Two patients failed to respond, but the third had a clinical remission after gamma globulin therapy. Given the usual chronic and relapsing course of Evans syndrome and the poor response to conventional therapy, we recommend that high dose i.v. gamma globulin be considered an alternative therapy in the management of these patients.

Adolescent↗
PubMed1985

Stromal and peripheral eosinophilia in cervical carcinoma.

One hundred cases of Stage IB cervical carcinoma treated with radical hysterectomy and pelvic lymphadenectomy at University Hospital of Jacksonville, Florida between 1973 and 1982. Eight patients were found to have tumor stromal eosinophilia on pathology review. Thirteen patients showed eosinophilia in their peripheral smears. Statistical analysis did not reveal a significant recurrence rate in patients with either peripheral or stromal eosinophilia.

Adult↗
PubMed1976

Low dose bleomycin and methotrexate in cervical cancer.

Twenty patients with recurrent and disseminated carcinoma of the cervix were treated with Bleomycin, 10 mg/m2 weekly and Methotrexate, 10 mg/m2 every fourth day. Twelve of the 20 (60%) had a greater than 50% shrinking of measured tumor masses lasting a median remission time of 7.5 months. The data suggest that combination protracted chemotherapy with these drugs of metastatic cervical cancer might improve the outlook of patients with this condition.

Bleomycin↗
PubMedDate not supplied

Antiphospholipid antibodies and coagulation regulatory protein abnormalities in children with pulmonary emboli.

PURPOSE: To evaluate the demographics, presentation, family history, and laboratory findings in children with clinically recognized pulmonary emboli. METHODS: Data were collected about children with clinically recognized pulmonary emboli from 1987 to 1994 at two pediatric hematology referral centers. RESULTS: Sixteen children, mean age 11.8 years (standard deviation 4.69 years) including 11 boys were affected. Lower extremity thromboses were present in 7/14 children evaluated. Eight of the 16 children were apparently well before development of pulmonary emboli; seven were found to have antiphospholipid antibodies. None of the 15 children tested were antithrombin III deficient. One of 14 children tested was protein C deficient. Three of 13 children tested were protein S deficient or had a free protein S antigen at the fifth percentile. One of 10 children tested had an acquired dysfibrinogenemia. Two of nine children tested had the Factor V Leiden mutation. CONCLUSIONS: Our limited data suggest at least 70% of children with pulmonary emboli referred for hematology evaluation have antiphospholipid antibodies and coagulation regulatory protein abnormalities.

Adolescent↗
PubMedDate not supplied

Mild hemophilia in children: prevalence, complications, and treatment.

PURPOSE: To review the natural history of mild hemophilia (factor VIII or IX level >5% and <50%), including presentation and diagnosis, characteristics of bleeding episodes, and therapy, at two hemophilia treatment centers. METHODS: Inpatient and outpatient records of 55 patients <17 years old with factor VIII or IX levels of 5 to 50% were reviewed and bleeding episodes for which medical attention was sought were analyzed. RESULTS: Five of the 55 patients were girls. Girls and patients with no family history of hemophilia were diagnosed at 5.5 and 5.3 years of age, respectively, compared to 2.8 years overall. Thirty-five patients were diagnosed because of a positive family history. No bleeding occurred in 18 patients; 190 bleeding episodes occurred in 37 patients. Most bleeding occurred in muscle/soft tissue (101 episodes) or joints (57 episodes) and were associated with trauma (174 episodes). CONCLUSIONS: Mild hemophilia may affect females more often than is appreciated. Delays in diagnosis and treatment may occur unless the variability in presentation is recognized.

Adolescent↗