Assessment of relative uptake by mandibular condyles in a "normal" population.

Hyperplasia of the mandibular condyle is self-limiting, but can lead to facial asymmetry, malocclusion, pain, and dysfunction of the temporomandibular joint (TMJ). Bone scintigraphy, particularly with single photon emission computed tomography (SPECT), is effective in assessing relative condylar uptake, but we know of no standardised methods or values. Our aim, therefore was to validate the values currently used to measure relative condylar uptake in our population. Between December 2015 and June 2018 44 patients had skull SPECT (15 male and 29 female patients, whose ages ranged from 4-33 years). They were having bone scans (hydroxydiphosphonate (HDP) -99MTc, 740 MBq ev) for unrelated reasons and had no known abnormalities of the head, facial asymmetry, or symptoms of the TMJ. Two research workers measured the relative uptake between the condyles using the summed transaxial images. The Hospital Ethics Committee approved the investigation. The maximum difference in condylar uptake was 8.33% with research worker 1 and 8.77% with research worker 2, and the mean (SD) differences were 3.03 (0.17) % and 3.29 (0.18) %, respectively. Data were tested for normality, and the t test and one-way ANOVA were used to assess the significance of differences. None was found in total counts either between sexes or age groups, and there were none between the total counts measured by the two research workers. We conclude that our results are within the published ranges, and the variation in condylar uptake was less than 5% in 37/44 patients, and in none was it 9% or more. When the results indicate less than 10%, but there is a high clinical suspicion of active hyperplasia, surgeons should use their clinical judgement to decide whether condylar surgery is required.

Bulked segregant analysis of the pirarucu (Arapaima gigas) genome for identification of sex-specific molecular markers.

Arapaima gigas (Osteoglossidae) is one of the largest fish species in the Amazon Basin, attaining lengths of over 2.5 m and weights of over 100 kg. Its flesh is prized, and it has great potential for production in aquaculture systems. However, live pirarucu cannot be reliably sexed visually, even after sexual development, since this species does not have clear external sexual dimorphism. Simple and inexpensive methods for sexing immature pirarucu based on DNA markers would facilitate production of this species in commercial operations. We analyzed A. gigas male and female DNA pools with 566 RAPD primers, generating 2609 fragments, with an estimated 1341 segregating polymorphic markers, and an estimated average spacing of 714 kb, which corresponds to less than 0.1% of the species' genome. Two putative sex-specific fragments were initially identified in bulked samples; but they were not confirmed in a study of individual male and female samples. We suggest that A. gigas has developed a non-chromosomal system of sex determination or, alternatively, that the species has undergone a recent loss of the chromosome carrying the sex-determining locus.

Isolation of the pituitary gonadotrophic α-subunit hormone of the giant amazonian fish: pirarucu (Arapaima gigas).

The cDNAs of the α-subunit of the pituitary gonadotrophic hormones (GTHα) of fish of the order Osteoglossiformes or the superorder Osteoglossomorpha have never been sequenced. For a better understanding the phylogenetic diversity and evolution of PGHα in fish and for future biotechnological synthesis of the gonadotrophic hormones (ag-FSH and ag-LH), of Arapaima gigas, one of the largest freshwater fishes of the world, its GTHα cDNA was synthesized by reverse transcriptase and the polymerase chain reaction starting from total pituitary RNA. The ag-GTHα-subunit was found to be encoded by 348 bp, corresponding to a protein of 115 amino acids, with a putative signal peptide of 24 amino acids and a mature peptide of 91 amino acids. Ten cysteine residues, responsible for forming 5 disulfide linkages, 2 putative N-linked glycosylation sites and 3 proline residues, were found to be conserved on the basis of the known sequences of vertebrate gonadotrophic hormones. Phylogenetic analysis, based on the amino acid sequences of 38 GTHα-subunits, revealed the highest identity of A. gigas with members of the Acipenseriformes, Anguilliformes, Siluriformes and Cypriniformes (87.1-89.5 %) and the lowest with Gadiformes and Cyprinodontiformes (55.0 %). The obtained phylogenetic tree agrees with previous analysis of teleostei, since A. gigas, of the order of Osteoglossiformes, appears as the sister group of Clupeocephala, while Elopomorpha forms the most basal group of all other teleosts.

Identification of new repetitive element in Leptospira interrogans serovar copenhageni and its application to PCR-based differentiation of Leptospira serogroups.

A new repetitive DNA element was identified in an isolate of Leptospira interrogans serovar copenhageni from a patient in Salvador, Brazil. A Sau3A genomic library from this strain was constructed and screened for repetitive DNA elements. An insert of 438 bp (Rep1) from one library clone hybridized to multiple chromosomal DNA fragments resolved electrophoretically after digestion with BamHI, HindIII, and MfeI. A single oligonucleotide primer, designated iRepl, was designed to generate multiple PCR amplicons of various electrophoretic mobilities in a PCR typing method. The method distinguished strains belonging to the eight pathogenic and three saprophytic species of the genus Leptospira. Clinical isolates obtained during urban epidemics between 1996 and 1998 in Salvador, Brazil, were analyzed by this PCR method. Although the iRep1 primer was unable to discriminate strains among L. interrogans serovar copenhageni isolates, it was able to differentiate strains belonging to different species and serogroups of Leptospira identified in Salvador. This PCR-based method may provide a faster and less expensive alternative to serologic tests used in reference laboratories.

Expression of adhesion molecules in chronic B-cell lymphoproliferative disorders.

BACKGROUND AND OBJECTIVE: Abnormalities in the expression of cell adhesion molecules (CAM) are thought to influence the patterns of intranodal growth and hematogeneous spread of malignant cells in chronic lymphoproliferative disorders (LPD). Therefore, the characterization of CAM phenotypic profiles of the neoplastic clones in LPD may help to identify distinct subtypes with prognostic implications. In this work we sought to investigate whether the expression of CAM by circulating malignant cells in patients with B-cell LPD differed from that of normal peripheral blood B-lymphocytes (PBL) and whether the observed phenotypic patterns could be correlated to other biological and clinical parameters of known clinical relevance. DESIGN AND METHODS: Peripheral blood mononuclear cells were obtained from 148 patients with B-cell chronic lymphocytic leukemia (B-CLL), 52 with B-cell non-Hodgkin lymphomas (NHL) and 10 with hairy cell leukemia (HCL). The expression of CAM was analyzed by flow cytometry using monoclonal antibodies against CD49d, CD29, CD11a, CD11b, CD11c, CD18, CD62L, CD54 and CD44. RESULTS: All CAM were detected in normal peripheral blood B-lymphocytes, except CD11c and CD54, which were present in only a minority of cells. Fluorescence mean channel values (FMC) showed that all molecules, with the exception of CD44, were expressed with dim intensity. Emerging patterns of CAM expression, as assessed by FMC values, were observed in different LPD: thus, B-CLL is characterized by a very low expression of CD49d/CD29 and beta 2 integrins. In this disorder, CD49d/CD29, CD11a, and CD54 increase with tumor burden; NHL show high expression of CD29 and CD54; strong expression of all molecules (except CD11a) was found in HCL, particularly CD11c (FMC values 60 times higher than normal). CD62L was faintly expressed in all diagnostic groups, whereas CD11c showed consistently high FMC values. INTERPRETATION AND CONCLUSIONS: The data shows that the phenotypic characterization of LPD can be further refined by the analysis of their patterns of CAM expression which may help to identify distinct subsets within each nosological group.