Use of antibacterial prophylaxis for patients with neutropenia. Australian Consensus Guidelines 2011 Steering Committee.

The use of oral prophylactic antibiotics in patients with neutropenia is controversial and not recommended by this group because of a lack of evidence showing a reduction in mortality and concerns that such practice promotes antimicrobial resistance. Recent evidence has demonstrated non-significant but consistent, improvement in all-cause mortality when fluoroquinolones (FQs) are used as primary prophylaxis. However, the consensus was that this evidence was not strong enough to recommend prophylaxis. The evidence base for FQ prophylaxis is presented alongside current consensus opinion to guide the appropriate and judicious use of these agents. Due consideration is given to patient risk, as it pertains to specific patient populations, as well as the net effect on selective pressure from antibiotics if FQ prophylaxis is routinely used in a target population. The potential costs and consequences of emerging FQ resistance, particularly among Escherichia coli, Clostridium difficile and Gram-positive organisms, are considered. As FQ prophylaxis has been advocated in some chemotherapy protocols, specific regard is given to whether FQ prophylaxis should be used to support these regimens. The group also provides recommendations for monitoring and surveillance of emerging resistance in those centres that have adopted FQ prophylaxis.

Identification of a cryptic t(5;7) reciprocal translocation by fluorescent in situ hybridization.

Fluorescent in situ hybridization (FISH) identified a cryptic balanced reciprocal translocation in the mother of an infant with the cri-duchat syndrome. A biotinylated probe from a flow-sorted chromosome 5 cosmid library was used to show the distal deletion of 5p15.2 in the propositus and a translocation of this segment to the distal end of 7 at 7p21 in his mother. In a subsequent pregnancy, the fetus was shown to have normal chromosomes using the same 5 cosmid library probe and a locus-specific probe derived from the 5p15.3 region. The importance of incorporating FISH into the routine diagnostic laboratory is discussed.

Prenatal application of fluorescent in situ hybridization (FISH) for identification of a mosaic Y-chromosome marker, idic(Yp).

An amniocentesis was performed at 13.3 weeks' gestation for advanced maternal age. A mosaic sex chromosome pattern was found: of 50 cells examined, 34 had a 45,X karyotype. In 14 cells with a modal number of 46, a recognizable Y was substituted by a small non-fluorescent marker. C-banding identified the marker as an isodicentric in 12 cells. In two cells, the non-fluorescent marker appeared to be monocentric and looked like a non-fluorescent del (Yq), but could have been an isodicentric Y with inactivation of one of the centromeres. Two cells with a modal number of 47 showed two copies of the monocentric marker. Fluorescent in situ hybridization with an alpha satellite Y-specific centromeric probe confirmed the Y-chromosome origin of the markers and allowed for more accurate prenatal diagnostic information.

Endothelin-1 receptor binding assay for high throughput chemical screening.

An endothelin-1 (ET-1) receptor-binding assay, in microtiter format, has been developed for use in high throughput chemical or natural product screening. A rat smooth muscle, clonal cell line derived from embryonic thoracic aorta and designated A10 has been shown to consistently express high-affinity ET-1 receptors. A 96-well microtiter filtration plate, with individual PVDF membranes attached to the bottom of each well, was used for separation. In saturation binding assays, using [125I]Tyr13-ET-1, Scatchard analysis was monophasic, indicating a single high-affinity population of receptors with Kd = 0.12 nM with approximately 40,000 receptors per cell. The Ki values for peptides, known to bind at the ET receptor, were as follows: ET-1, 0.14 nM; ET-2, 0.16 nM; sarafotoxin S6b, 0.6 nM; VIC, 0.2 nM; ET-3, 16 nM; and big human ET, greater than 1 microM. ET receptors on A10 cells were stable for at least 2 months when stored at -20 degrees C. The assay is suitable for automation, because it is stable and reproducible. This method gave a 90% reduction in radioactive waste compared to tissue homogenate assays that use glass fiber filtration and cell harvesters.

Loss of the Y chromosome associated with translocation t(6;9)(p23;q34) in a patient with acute nonlymphocytic leukemia.

A 34-year-old male with acute nonlymphocytic leukemia (ANLL) and a t(6;9)(p23;q34) is described, in whom loss of the Y chromosome had occurred in the t(6;9) clone. The leukemic blasts were relatively undifferentiated and there was no increase in marrow basophils. The unusual clonal evolution and hematologic features in this patient are compared to 27 previously documented cases with this translocation.

Mycosis fungoides/Sezary's syndrome progressing to immunoblastic sarcoma. A T-cell lymphoproliferation with both helper and suppressor phenotypes.

Multiparameter studies of an unusual patient exhibiting cutaneous manifestations of both mycosis fungoides and Sezary's syndrome are presented. The neoplastic cells of dermal and nodal infiltrates and peripheral blood expressed both helper and suppressor immunologic phenotypes. Cytofluorographic analysis of cells isolated from lymph node and peripheral blood showed a population of neoplastic cells that were stained with the monoclonal antibodies OKT 3, 4, 8, and 11. Immunoperoxidase staining of frozen sections with monoclonal antibodies Leu 1, 2, and 3 provided a topographical identification of an identically marking population of cells in dermis and lymph node. In light of current models depicting normal T-cell lineage, the authors suggest that the neoplastic population in this patient, expressing both helper and suppressor phenotypes, reflected a phenotypic stage of immunologic maturation (OKT 6-, OKT 10-, OKT 3+, OKT 11+, OKT 4+, OKT 8+) in which the neoplastic cells had not yet segregated into distinctive T-cell subsets. While excess helper activity was suggested by serum hypergammaglobulinemia, in vitro helper and suppressor function was not determined. The range of studies employed illustrates the wide variety of technics required to adequately characterize complex clinico-immunopathologic disorders, as represented by this case, and the wealth of information that can be gleaned.

Changes in dental students' personal needs and values.

Personality characteristics of dental students were studied longitudinally by means of the Allport-Vernon-Lindzey Study of Values and Edwards Personal Preference Schedule. There were no significant differences when 21 scale scores of seniors were compared to the scores obtained from the same students as freshmen. The lack of significant change indicated a minimal effect of dental education on the personal needs, values, and attitudes of students. Thus, it is essential that faculty know as much as possible about applicants' values and needs prior to their admission to dental school. Knowledge of these personality characteristics is also essential for teaching and reinforcing those attitudes and values that are believed to assist students in developing well-integrated personal and professional lives.

Dental students' personality: a Jungian perspective.

The Myers-Briggs Type Indicator (MBTI) was employed to measure the nature and strength of dental students' various basic preference in perceiving and making judgments. The MBTI yields four sets of scores--extrovert-introvert (E-l), sensing-intuitive (S-N), thinking-feeling (T-F), and judging-perceptive (J-P)--and represents 16 personality types that define these preferences. The sample consisted of five classes at the University of Mississippi School of Dentistry (n = 217). The data indicated that the largest group (32 students) was ESFJ, while the next largest (30) was ESTJ. The least frequently represented groups were the INTP (3), the INFP (7), the INTP (7), and the ENTP (7). Dental students exhibited characteristics different from those of students in business, engineering, social work, medicine, and other fields. These findings have implications for admissions committee decisions as well as for the organization and curriculum of the dental school.

Convoluted lymphocytic lymphoma in adults: a clinicopathologic entity.

Twelve adults had a distinct clinicopathologic type of malignant lymphoma that closely resembles the mediastinal lymphomas of childhood. Nine patients presented with mediastinal masses, and seven had symptoms related to intrathoracic compression. Seven patients presented with or developed leukemia, and in four of these patients the central nervous system (CNS) became involved. Structurally, the tumor cells had a distinctive stippled chromatin pattern, in addition to the characteristic nuclear convolutions. Tumor cells from five patients were studied immunologically, and, in each case, the tumor cells formed rosettes with sheep erythrocytes. The response to combination chemotherapy was rapid and dramatic, but usually transient, with relapse in the CNS or previously involved sites. The above data strongly suggest that these cases represent a distinct clinicopathologic entity that should be treated similarly to childhood leukemia and lymphoma, with intensive multiple agent induction, CNS prophylaxis, possibly radiation therapy to initially involved sites, and prolonged maintenance.

Morphologic and cytochemical comparison of human lymphoblastoid T-cell and B-cell lines: light and electron microscopy.

Human lymphoblastoid cell lines characterized as T- or B-cells by various markers were compared morphologically and cytochemically by light and electron microscopy. Distinct differences in nuclear morphology, amount of cytoplasm, pyroninophilia, and periodic acid-Schiff (PAS) staining enabled us to discriminate between T- and B-cell lines. T-cells had nuclei with an irregular configuration, stippled heterochromatin, and small or absent nucleoli. The scanty cytoplasm of T-cells contained intensely stained, PAS-positive globules and was less pyroninophilic than the cytoplasm of B-cells. B-cells had more rounded, uniform, vesicular nuclei with prominent nucleoli and peripheral heterochromatin. The cytoplasm of B-cells was abundant and strongly pyroninophilic. Transmission electron microscopy generally confirmed these morphologic differences. These findings supported our contention that consistent cytologic features concordant with immunologic markers make it possible to identify certain lymphomas as being of B- or T-cell origin on purely morphologic grounds.