The C57BL/10Bg sps/sps mouse: a mutant with absence-like seizures; neurochemical and behavioral correlates

C57BL/10Bg sps/sps mice display behavioral arrest, similar to generalized absence seizures. Compared with the parent strain C57BL/10Bg SPS/SPS, the activities of glutamate decarboxylase (GAD, E. C. 2.6.1.15), GABA aminotransferase (GABA-T, E. C. 2.6.1.19), aspartate aminotransferase (ASP-T, E. C. 2.6.1.1), and glutamate dehydrogenase (GDH, E. C. 1.4.1.3) in whole brain crude supernatant were significantly reduced in the sps/sps mice. Alanine aminotransferase activity (ALA-T, E. C. 2.6.1.2), was not altered in any of the strains, and normalization of GAD, GABA-T and GDH activities by that of ALA-T, further revealed significant differences between the normal strain (SPS/SPS), the heterozygotes (SPS/sps), and behavioral arrest (sps/sps) mice. These results suggest the possible involvement of GABAergic and glutamatergic neurotransmission in the absence-like behavior displayed by sps/sps mice. Open field behavior of C57BL/10Bg sps/sps mice is characterized by periods of marked inactivity which easily distinguish affected homozygotes, from their heterozygotes littermates.     

Four new HLA class I alleles in Cauacasoids

Four new HLA classical class I alleles in the three loci are described in Caucasian individuals. A*3012 was first suspected by an abnormal serologic pattern that would be explained by the single amino acid substitution at the A30-specific Ser17. B*270505 differs from B*270502 in a silent substitution at an up to now constant position in the B locus. B*3541 encodes for a new Cys at position 118 that has not been encountered in neither human nor primate alleles. Cw*0716 seems to be originated by a large-scale interallelic recombination event between Cw*0701/*0706/*0718 and Cw*020202, giving rise to a new antigen-binding cleft conformation.     

Cathepsin C gene: First compound heterozygous patient with Papillon-Lefèvre syndrome and a novel symptomless mutation

Papillon-Lefèvre syndrome (PLS) has recently been shown to be caused by mutations in the cathepsin C gene resulting in periodontal disease and palmoplantar keratosis. Thirteen different homozygous mutations have been characterised in PLS patients of different ethnic origin. In the present paper, a PLS patient is described who carries two novel mutations (706G>T and 872G>A) in the paternal and maternal chromosomes, respectively. This is the first compound patient described so far. In addition, a novel symptomless mutation (458C>T) in the cathepsin C gene is described in three homozygous individuals. Thus, not all mutations should be considered as a cause of disease, whether case studies or general population screening is performed. Another already described mutation that provoked the Haim-Munk syndrome (HMS) in Indian Jews has also been found to give rise to PLS in a Spanish family from Madrid. On the other hand, PLS patients are ameliorated by retinoids, which indicates that retinoids may be used as therapeutic agents in this immune system deficiency.     

Looking for ferns: optimization of digestion pretreatment in fluorescence in situ hybridization (FISH) technique on paraffin-embedded tissues.

Fluorescence in situ hybridization (FISH) is a useful cytogenetic technique for the detection of chromosome aberrations. However, applying this technique routinely on paraffin-embedded tissue is hampered by technical problems. The efficiency of hybridization is influenced by formalin fixation time, and this may vary considerably between specimens. We present a simple method for improving hybridization by microscopically monitoring the time of enzymatic digestion. To establish optimal digestion time, enzymatic digestion was stopped at 3-minute intervals for biopsies and 10-minute intervals for autopsies in 24 paraffin-embedded samples. At every stop, tissue morphology was examined under light microscopy to determine if observed changes could be correlated with subsequent FISH results. The appearance of fernlike formations was found to mark the optimal digestion time that produced the strongest hybridization signals. Using this method of digestion time control, an additional 41 cases were evaluated for FISH with various types of probe. Monitoring under the microscope could be more spaced if the morphology did not change after the first visual control and could be adapted to the type of sample (in general, endoscopic samples, total digestion time of about 10 min; routine biopsies, 15 to 30 min; autopsy samples, 20 to 40 min). In every case, the appearance of the fernlike pattern correlated with proper hybridization signal. Monitoring digestion time for the appearance of fernlike structures is a useful method for improving reproducibility of FISH technique on paraffin-embedded samples. It is particularly useful when dealing with samples under heterogeneous fixation conditions (consultations, autopsies, etc.), because it eliminates the need for repetition.     

Evolution of MHC-G in humans and primates based on three new 3'UT polymorphisms

MHC-G is a class Ib (non-classical) major histocompatibility complex (MHC) whose functional and evolutionary characteristics are still under scrutiny. The study of noncoding sequences in the MHC genes may provide important phylogenetic information. In this work we have sequenced the MHC-G exon 8, which encodes for the 3'UT region, in different species of primates. It has been shown that: (1) a previously described 14 base pair (bp) deletion polymorphism is human-specific and the HLA-G alleles may be classified according to its absence or presence; (2) another newly described 3 bp deletion/insertion polymorphism is also human-specific; and (3) another newly described 51 bp deletion polymorphism is common to Pongidae and humans, but is not found in other primates belonging to the Cercopithecinae family. A hypothesis on the evolutionary pathway of this gene is put forward in the light of these findings.     

IgH, TCR-gamma, and TCR-beta gene rearrangement in 80 B- and T-cell non-Hodgkin's lymphomas: study of the association between proliferation and the so-called "aberrant" patterns.

The current study analyzes the rearrangement pattern of immunoglobulin H (IgH), T-cell receptor (TCR)-gamma, and TCR-beta genes in a group of 80 non-Hodgkin's lymphomas (NHL) of different histologic subtypes (43 B-cell and 37 T-cell types). The sensitivity and specificity provided by polymerase chain reaction amplification of these loci are evaluated. The association between the proliferation index and the presence of the so-called "aberrant" or "dual" rearrangements is also considered. Ninety-one percent of B-cell NHL showed IgH gene monoclonality, and 21% also exhibited a monoclonal pattern in one of the TCR genes. Among T-cell NHL, the sensitivity of the study was 65% for the TCR-gamma gene and 46% for the TCR-beta gene. The total sensitivity was 76%, amplifying both loci. IgH gene aberrant rearrangements were observed in 16% of T-cell neoplasms. A substantial percentage of dual rearrangements were detected in precursor and mature B- and T-cell NHL. B-cell NHL showed a tendency toward higher values of proliferation when aberrant rearrangements were present; however, this trend was not significant. Furthermore, in the case of T-cell NHL there was a significant negative association between these two variables.     

Ontogeny of the endocrine cells of the intestine and rectum of sea bass (Dicentrarchus labrax L.): an ultrastructural study

Several endocrine cell types were ultrastructurally characterized during the differentiation of the intestine and rectum of sea bass (Dicentrarchus labrax L.) larvae. Only one cell type (type I) was found in the posterior region of the undifferentiated gut of 5-day-old larvae (phase I). Types V and VI were found in both the intestine and rectum, types II, III and IV in the intestine, and types VII and VIII in the rectum of 9- and 12-day-old larvae (phase II), the rectum alone showing signs of functional differentiation. In phase III larvae, in which both the intestine and rectum were differentiated, types IX, X, XI, XII, XIII, XIV and XV were found in the intestine, only types X, XI and XII being seen in the rectum. Besides these, a new cell type, XVI, was observed in the intestine of 55- and 60-day-old larvae (phase IV), in which the digestive tract was completely differentiated. The endocrine cells appearing in phases I and II showed very scarce secretory granules and the ultrastructural features of undifferentiated cells. Some endocrine cell types in the earliest developmental stages were related to some of those found later. A maturational process of the endocrine cell types paralleled the differentiation of the intestine and rectum, with an apparent increase in the number of secretory granules accompanying organelle development.     

Nonmyeloablative stem cell transplantation is an effective therapy for refractory or relapsed hodgkin lymphoma: results of a spanish prospective cooperative protocol.

We report the results of reduced-intensity conditioning allogeneic stem cell transplantation (allo-RIC) in patients with advanced Hodgkin lymphoma (HL). Forty patients with relapsed or refractory HL were homogeneously treated with an RIC protocol (fludarabine 150 mg/m(2) intravenously plus melphalan 140 mg/m(2) intravenously) and cyclosporin A and methotrexate as graft-versus-host disease (GVHD) prophylaxis. Twenty-one patients (53%) had received >2 lines of chemotherapy, 23 patients (58%) had received radiotherapy, and 29 patients (73%) had experienced treatment failure with a previous autologous stem cell transplantation. Twenty patients (50%) were allografted in resistant relapse, and 38 patients received hematopoietic cells from an HLA-identical sibling. Five patients (12%) died from early transplant-related mortality (before day +100 after allo-RIC). One-year transplant-related mortality was 25%. Acute GVHD developed in 18 patients (45%). Chronic GVHD developed in 17 (45%) of the 31 evaluable patients. The response rate 3 months after the allo-RIC was 67% (21 [52%] complete remissions and 6 [15%] partial remissions). Eleven patients received donor lymphocyte infusions (DLIs) for disease relapse. The response rate after DLI was 54% (3 complete remissions and 3 partial remissions). Overall survival (OS) and progression-free survival (PFS) were 48% +/- 10% and 32% +/- 10% at 2 years, respectively. Refractoriness to chemotherapy was the only adverse prognostic factor for both OS (63% +/- 12% versus 35% +/- 13%; P = .05) and PFS (55% +/- 16% versus 10% +/- 9%; P = .006). For patients with failure of a prior autologous hematopoietic stem cell transplantation, results were especially good for those who experienced late relapses (>/=12 months: 2-year OS and PFS were 75% +/- 16% and 70% +/- 18%, respectively). These data suggest that allo-RIC is feasible in heavily pretreated HL patients and has an acceptable early transplant-related mortality. Results are better in patients allografted in sensitive disease. Both responses observed after the development of GVHD and DLI may suggest a graft-versus-HL effect. Allo-RIC has to be considered an effective therapeutic approach for patients who have had treatment failure with a previous autologous hematopoietic stem cell transplantation.