Thermally tunable electromagnetic surface waves supported by graphene loaded indium antimonide (InSb) interface.

The thermal agitation plays a vital role in tunability of optoelectronic, structural and chemical characteristics of the temperature sensitive materials. Graphene enables the THz optics, due to its unprecedent controlling characteristics over the traditional materials. The influence of temperature on the monolayer graphene is very negligible due to its low free charge carrier density, to enhance the thermal sensitivity of graphene, the graphene loaded temperature sensitive material interface has been proposed. A theoretical analysis has been carried out on temperature dependent propagation characteristics of electromagnetic surface waves supported by the graphene loaded semi-infinite indium antimonide (InSb). The InSb has been taken as temperature sensitive material. The Drude model has been used for the modeling of InSb in the THz region while the modeling of the graphene has been done by random phase approximation-based Kubo's formulism. To realize the graphene loaded indium antimonide interface, the impedance boundary conditions (IBCs) have been employed. The numerical analysis has been conducted to analyze the influence of temperature on the characteristics of electromagnetic surface waves i.e., dispersion curve, effective mode index (Neff), penetration depth (δ), propagation length (Lp), phase speed (Vp) and field profile, propagating along the graphene loaded InSb. In all the numerical results, the temperature variation has been considered from 200 to 350 K. It has been concluded that the graphene-InSb interface provides more temperature assisted tunability to the interfacial surface modes, commonly known as surface waves, as compared to monolayer graphene. Further, the graphene parameters can play a vital role in the dynamical tuning of electromagnetic surface waves in THz to IR frequency range. The numerically computed results have potential applications in designing of thermo-optical waveguides, temperature assisted communication devices, thermo-optical sensors and near field thermal imaging platforms.

Patterns of use of group O, Rh-negative red cells in a large metropolitan area and an action plan to control utilization.

BACKGROUND: In southeastern Michigan, the group O, Rh-negative (O-) red cell supply was below emergency levels during one-sixth of 1994, despite 43-percent overcollection of O- red cell units relative to the size of the O- patient population. O- red cell units are overutilized because of their universal ABO and Rh compatibility. This study evaluated how hospitals in a large metropolitan area utilized O- red cell units, so that strategies could be devised to reduce O- usage. STUDY DESIGN AND METHODS: Through an O- red cell utilization survey, 56 hospitals were encouraged to collect three months' worth of transfusion data, either prospectively or retrospectively. O- usage was compared to total red cell usage and categorized into transfusions to O- patients, those to non-O- patients, and the number of O- units that outdated. RESULTS: Of 40,616 units transfused in 38 hospitals, 3,535 (8.7%) were O-; 71 percent of the O- units were transfused to O- patients, 28 percent were transfused to non-O- patients, and 1 percent outdated. Hospital transfusions to O- patients appeared to correlate with the racial makeup of the patient population, while hospital transfusions to non-O- patients appeared to correlate with hospital size and the hospital's transfusion practices. CONCLUSION: O- red cell usage in a hospital is dependent on the racial and ethnic mix of the hospital's patient population, the amount of transfusion activity, and the hospital's transfusion practices. An understanding of the dynamics of O- usage allowed the development of strategies to decrease O- utilization.

Parathyroid stimulation after bleeding in man.

A role for the PTH-calcium axis in the normal bone-marrow response to bleeding or erythropoietin administration has been demonstrated in rats. We studied 20 autologous blood donors, each donating two units of blood, who served as a human bleeding model. Fifteen patients completed the study. Blood donations were followed by a significant increase in serum intact PTH (2.15 +/- 0.67 to 2.81 +/- 0.84 pmol/l; p = 0.0003) and protein-corrected total calcium (2.43 +/- 0.09 to 2.49 +/- 0.08 mmol/l; p = 0.2). All the individual values remained within the normal range. PTH weakly correlated with the reticulocyte count, but not with the corrected serum calcium. We conclude that moderate bleeding in humans is followed by a physiological increase in serum PTH and calcium.

Prognostic correlation of plasma cell acid phosphatase and beta-glucuronidase in multiple myeloma: a Southwest Oncology Group study.

In 1982 a randomized trial of either alternating or syncopated VMCP/VBAP regimens for the treatment of active multiple myeloma was begun (Southwest Oncology Group Study 8229/30). A concurrent investigation was undertaken to evaluate the clinical importance and significance of cytochemically stainable plasma cell acid phosphatase (AP) and beta-glucuronidase enzymes (BG). Pretreatment bone marrow aspirates were available for analysis from 399 patients for AP and 398 patients for BG. The AP scores ranged between 42 and 395, and the BG scores ranged between 1 and 346. There was a significant increase of AP (P = .001) and BG (P = .002) in multiple myeloma as compared with a set of patients with benign plasmacytosis. The enzyme scores did not significantly relate to Ig idiotype of myeloma or other prognostic variables except that the BG scores varied significantly with the level of albumin (P = .03) and hemoglobin (P = .01). Analysis of patient groups with different levels of enzyme scores showed that 61 of 398 patients with an AP score of less than 130 had a poorer median survival of 1.7 versus 2.8 years for patients with higher scores (P = .001). In the multivariate analysis of survival, low AP score was an important prognostic factor (P = .006), but BG did not contribute significantly. It is suggested that the subset of patients presenting with low AP should be considered for specialized or more aggressive therapy.

Platelet function and structure in myeloproliferative disease, myelodysplastic syndrome, and secondary thrombocytosis.

Platelet function and morphologic characteristics were evaluated in 43 patients with myeloproliferative disease (MPD), 5 patients with myelodysplastic syndrome (MDS), and 7 patients with secondary thrombocytosis (ST). Platelet Factor IV (PF4) and B-thromboglobulin (BTG) showed slight elevation in ST but significant elevation in all MPDs. They were either normal or slightly elevated in MDS. Defective platelet aggregation with one or more inducers was seen in 62% of all patients. An epinephrine-induced defect was the most consistent aggregation abnormality. Hyperaggregation and spontaneous aggregation were seen in 15% of patients. Of the eight patients who showed increased bleeding tendency, all eight showed defective aggregation with two or more inducers, five showed decreased surface activation response, as well as decreased or abnormal granules and dense tubular disarray in the transmission electron microscope (TEM) study. Seven patients had clinical evidence of recurrent arterial and venous thromboses. Five of these patients showed hyperaggregation response to adenosine diphosphate and collagen and abnormal Wu and Hoak platelet aggregate ratio. Four patients showed spontaneous aggregation on aggregometer. Surface activation response was significantly increased in five patients, and an increase in platelet granules by TEM study was seen in four patients. Primary thrombocythemia could be differentiated from secondary thrombocytosis (ST) by the presence of abnormal aggregation response and significantly increased PF4 and BTG in the former, and greatly elevated plasma fibrinogen and Factor VIII, as part of acute phase reactant response, in the latter.

Lupus anticoagulant associated with specific inhibition of factor VII in a patient with AIDS.

A 37-year-old intravenous drug abuser with acquired immune deficiency syndrome showed elevated activated partial thromboplastin time (APTT) and prothrombin time, normal thrombin time and fibrinogen, and borderline low platelet counts. The patient subsequently had a fracture of the left zygomatic arch, which did not produce uncontrollable bleeding. The coagulogram repeated at this admission showed persistent elevation of APTT. Further coagulation workup showed the presence of a lupus anticoagulant with mild specific inhibition of Factor VII. Platelet aggregation and Factor II levels were normal.

Essential thrombocythemia with acquired von Willebrand's disease.

Two patients with essential thrombocythemia showed a marked decrease in ristocetin-induced platelet aggregation in addition to other aggregation defects during routine aggregation studies for prolonged bleeding times. Further investigation revealed type I von Willebrand's disease (vWD) in one patient and a variant of vWD compatible with type IIA defect in the second patient. The latter patient had minor episodes of epistaxis clinically, while the patient with type I disease experienced excessive blood loss during menstrual periods. Both patients gave negative history for abnormal bleeding in the past or in their families. Both have had uneventful surgical procedures in the past, at which time bleeding times and basic coagulation test results were normal.

Diffuse nonsecretory osteosclerotic myeloma with extensive erythrophagocytosis.

A 51-year-old, black man presented with severe anemia and weakness. X-ray studies showed diffuse osteosclerosis involving most of his skeleton. He was documented to have similar bone changes on x-ray 5 years previously. Peripheral blood findings were suggestive of a myelophthisic anemia. Open biopsy of the iliac bone showed osteosclerotic myeloma. Secretion of abnormal protein could not be demonstrated through many examination of serum or urine. A unique finding at the autopsy was the presence of extensive erythrophagocytosis by the neoplastic plasma cells and macrophages.

Hemoglobin SO Arab and hemoglobin CO Arab diseases. Clinical and laboratory study.

A nine-year-old black female who had been considered to have Hb SC disease was admitted with pain of the leg, neck, and upper chest. She had also been hospitalized approximately 20 times for treatment of recurrent pain. Further investigation by citrate agar gel electrophoresis and peptide mapping disclosed that the child had Hb SO Arab disease. She had mild hepatosplenomegaly and the hemoglobin concentration was 10.2 gm/dl. The clinical presentation of Hb SO Arab disease of our patient resembled that of Hb SD disease and was more severe than is Hb SC disease. The mother was found to have Hb O Arab trait. Two of the patient's siblings from a different father were found to have Hb CO Arab disease, an extremely rare condition. These children, 8 and 12 years old, are clinically asymptomatic. Clinical and laboratory data are presented.

Hodgkin's disease in renal transplant recipients.

The association between renal transplantation and malignancy, particularly histiocytic lymphoma, is well known. Hodgkin's disease also occurs in renal transplant recipients. We report such a case and also review three other reports in the literatures. The Hodgkin's disease was insensitive to conventional MOPP chemotherapy in two of two, and was sensitive to combined MOPP-Bleomycin in one patient. The disease was rapidly fatal in three of four cases.

Essential thrombocythemia with transition into acute leukemia.

A 57-year-old black man with sustained platelet count of 2 million/mm3 and evidence of intermittent gastrointestinal bleeding was diagnosed as having essential thrombocythemia. Studies of bone marrow morphology, platelet aggregation, and other variables were confirmatory of the disease. The patient was treated briefly with low doses of Myleran for less than three weeks. He was then lost to follow-up study. Approximately 16 months later he reappeared complaining of recurrent nose bleeds. He was found to be pancytopenic and diagnosis of acute leukemia was made on the basis of bone marrow aspiration.

Type I dyserythropoietic anemia. A 30-year follow-up.

Dyserythropoietic anemias are extremely rare disorders which often are misdiagnosed as megaloblastic anemia, DiGuglielmo's syndrome, refractory sideroblastic anemia, paroxysmal nocturnal hemoglobinuria, or other hemolytic anemias. Dyserythropoietic anemia is now subclassified into four types, designated Types I through IV, depending upon light and ultrastructural morphology, erythrocyte immunology, and the course of the disease. This report details the findings in a case of Type I dyserythropoietic anemia that represented a puzzling case of anemia for over 30 years. Many modes of drug therapy, as well as splenectomy, were not helpful. Interestingly, the family history was non-contributory. A brief review of the literature dealing with dyserythropoietic anemia is included.

Congenital hepatic fibrosis and polycystic disease of kidneys with the roentgen appearance of medullary sponge kidney.

A family is presented in which four and possibly five members of a sibship of seven are affected with polycystic kidney with congenital hepatic fibrosis. The excretory urogram in this disease may be indistinguishable from that of medullary sponge kidneys. Therefore, it is suggested that family studies be undertaken when a diagnosis of medullary sponge kidney is made.