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To evaluate whether baseline visual field data and asymmetries between eyes predict the onset of primary open-angle glaucoma (POAG) in Ocular Hypertension Treatment Study (OHTS) participants.A new index, mean prognosis (MP), was designed for optimal combination of visual field thresholds, to discriminate between eyes that developed POAG from eyes that did not. Baseline intraocular pressure (IOP) in fellow eyes was used to construct measures of IOP asymmetry. Age-adjusted baseline thresholds were used to develop indicators of visual field asymmetry and summary measures of visual field defects. Marginal multivariate failure time models were constructed that relate the new index MP, IOP asymmetry, and visual field asymmetry to POAG onset for OHTS participants.The marginal multivariate failure time analysis showed that the MP index is significantly related to POAG onset (P0.0001) and appears to be a more highly significant predictor of POAG onset than either mean deviation (MD; P = 0.17) or pattern standard deviation (PSD; P = 0.046). A 1-mm Hg increase in IOP asymmetry between fellow eyes is associated with a 17% increase in risk for development of POAG. When threshold asymmetry between eyes existed, the eye with lower thresholds was at a 37% greater risk of development of POAG, and this feature was more predictive of POAG onset than the visual field index MD, though not as strong a predictor as PSD.The MP index, IOP asymmetry, and binocular test point asymmetry can assist in clinical evaluation of eyes at risk of development of POAG.

The IghViv family has been reported to consist of 13 different genes, only one of which is a pseudogene. The IghViv family member IghV4.21 is widely used, and is known to encode immunoglobulin specific for the red blood cell antigens I and i in germline configuration. We have previously reported a rearranged IghV4.21 gene, isolated from the marginal zone of normal human spleen, which has two large deletions in FR1 and FR2/CDR2. We have now identified the same IghV gene sequence rearranged to a different diversity (D) region, in plasma cells of the intestinal lamina propria in a different patient, suggesting that this sequence represents a new IghViv family pseudogene related to IghV4.21. 6 refs., 1 fig.

The elderly produce increased levels of antibodies to autologous antigens and are less able to make high-affinity antibodies to foreign antigens. Ig gene hypermutation is integral to the affinity maturation process but previous studies of hypermutation with age have yielded conflicting results. The cells studied have represented post-germinal center (GC) populations and, therefore, the results may be complicated by possible differences in activation history. We studied Ig genes from GC B cells to elucidate which factors in the affinity maturation process change with age. Age-related changes in the pattern of hypermutation were seen, although the analysis of variable region heavy chain (VH) genes and their lineage trees shows that an alteration in the mechanism of somatic hypermutation is unlikely. The changes are due to founder cell effects and/or the process of selection. Striking tissue-specific differences were seen. All measurements indicated that selection of Ig genes may decrease in Peyer's patch GC but increase in splenic GC with age. These tissue-specific differences highlight the importance of considering the activation and effector sites when studying immune senescence.

Treatment of [M(CO)3(η-C5Me5)]–(M = Mo or W) with Br[CH2]3 Br gives the metallapropanes [M{(CH2)3Br}(CO)3(η-C5Me5)]. Reaction of [Mo{(CH2)3Br}(CO)3(η-C5Me5)] with I– provides cis and trans carbenes [MoI(CO)2{[graphic omitted]}(η-C5Me5)]. Crystallisation of the mixture gives two crystal forms, one of which consists of pure trans isomer while the second consists of a mixture of predominantly two cis components (68.5 and 7.1%) with some trans isomer (24.4%) incorporated in the crystal. For the trans isomer, orthorhombic, a= 15.38(6), b= 15.65(8), c= 14.78(6)A, R 0.0665 for 1 335 independent reflections. For the cis isomer, monoclinic, a= 12.73(4), b= 9.26(3), c= 16.09(4)A, β= 108.68(9)°, R 0.0908 for 974 independent reflections. In tetrahydrofuran solution the two isomers slowly interconvert at ambient temperature. The reaction of Br– with [Mo{(CH2)3Br}(CO)3(η-C5Me5)] gives the carbene [MoBr(CO)2{[graphic omitted]}(η-C5Me5)] as predominantly the cis isomer. The reaction of CN– with [Mo{(CH2)3Br}(CO)3(η-C5Me5)] gives the trans carbene [Mo(CN)(CO)2{[graphic omitted]}(η-C5Me5)] while reaction with SCN– gives the cis carbene [Mo(NCS)(CO)2{[graphic omitted]}(η-C5Me5)]. Reaction of [W{(CH2)3Br}(CO)3(η-C5Me5)] with I– affords the iodo carbene [WI(CO)2{[graphic omitted]}(η-C5Me5)] as predominantly the trans isomer. Reaction of [Mo{(CH2)3Br}(CO)(η-C5Me5)] with [Fe(CO)2(η-C5H5)]– results in elimination of Br– and formation of the heterodimetalla-alkane species [(η-C5Me)(OC)3Mo(CH2)3Fe(CO)(η-C5H5)].

In this study we have used cloned gene probes for human glutathione peroxidase (GPX), rat cytochrome P-450IVA1 and rat cytochrome P-450IIE1 to detect homologous sequences in RNA from the hepato-pancreas of Mytilus edulis. The presence of sequences hybridising to the GPX and P-450IVA1 probes, but not to the P-450IIE1 probe, confirms the ancient origin of the former genes and indicates that conserved-sequence DNA probes from higher organisms can be used to examine the structure and function of genes of environmental interest in marine organisms.

Fungal infections from eye bank-preserved corneas have led us to search for antifungal agents that will eliminate yeast and mold in McCarey-Kaufman (MK) medium and concurrently be nontoxic. Amphotericin B, natamycin, nystatin, and clotrimazole were tested in synergistic combinations in vitro against nine yeast and six mold specimens. For average yeast and mold concentrations of 3.4 X 10(4) and 1.36 X 10(4) colony-forming units (CFUs)/mL at 5 degrees C, and 3.36 X 10(4) and 2.3 X 10(3) CFUs/mL at 37 degrees C, respectively, a synergistic combination of all four drugs at one twelfth the minimal fungicidal concentrations proved fungicidal. This synergistic combination did not alter donor human corneal morphology under specular microscopy, nor did it inhibit rabbit corneal endothelial cell division preserved and propagated in antifungal supplemented MK medium. The synergistic drug mixture did prove to be fungicidal when the endothelial cells were challenged with fungal inoculum.

B cells are present in human fetal intestine from approximately 14 weeks of gestation. Here we show that this population includes mature, dividing B cells. These are large cells with dendritic processes, resembling human thymic B cells. In addition, we observed IgM+, light chain−, and CD20− cells and local expression of V pre-B, demonstrating that the human fetal intestine is a site of B cell development. Ig VHDJH gene sequencing can confirm clonal identity of B cells. Identification of the same IgVH4–34 sequence in serial sections in two fetuses confirmed local accumulation of related cells in each case. IgVH4–34 was also amplified from an additional two samples, and the D and J repertoire compared with a unique database of unselected VH4–34 genes from postnatal gut. Distinguishing characteristics of Ig λ genes in postnatal gut were also studied in the fetus. According to these parameters, fetal and postnatal B cells are unrelated.

Immunologically, the parotid salivary gland is an effector site that secretes large quantities of polyspecific Abs into the saliva, mainly of the IgA isotype. It is considered to be part of the common mucosal immune system but the inductive site for the Ab-producing cells of the salivary gland has not yet been clearly identified. The origin and diversity of cells of B lineage can be investigated by analyzing their Ig heavy chain genes (IgH). We have obtained sequences of IgM and IgA VH4–34 genes from plasma cells in human salivary gland, duodenal lamina propria, and splenic red pulp. Related sequences were found in different areas sampled within each tissue studied, indicating that the plasma cells carrying these genes are widespread with limited diversity. Examples of related IgH genes that are isotype switched were also seen in the salivary gland. The genes from plasma cells of the salivary gland were highly mutated, as were duodenal plasma cell sequences. The level of mutation was significantly higher than that seen in splenic plasma cell sequences. Analysis of CDR3 regions showed that the sequences from salivary gland had significantly smaller CDR3 regions than sequences from spleen, due to differences in number and type of DH regions used. Sequences from duodenum also had smaller CDR3 regions. Therefore, plasma cells from human duodenum and salivary gland showed characteristics that differed from those of human splenic plasma cells.

The B cell receptor (BCR) repertoire is highly diverse. Repertoire diversity is achieved centrally by somatic recombination of immunoglobulin (Ig) genes and peripherally by somatic hypermutation and Ig heavy chain class-switching. Throughout these processes, there is selection for functional gene rearrangements, selection against gene combinations resulting in self-reactive BCRs, and selection for BCRs with high affinity for exogenous antigens after challenge. Hence, investigation of BCR repertoires from different groups of B cells can provide information on stages of B cell development and shed light on the etiology of B cell pathologies. In most instances, the third complementarity determining region of the Ig heavy chain (CDR-H3) contributes the majority of amino acids to the antibody/antigen binding interface. Although CDR-H3 spectratype analysis provides information on the overall diversity of BCR repertoires, this fairly simple technique analyzes the relative quantities of CDR-H3 regions of each size, within a range of approximately 10-80 bp, without sequence detail and thus is limited in scope. High-throughput sequencing (HTS) techniques on the Roche 454 GS FLX Titanium system, however, can generate a wide coverage of Ig sequences to provide more qualitative data such as V, D, and J usage as well as detailed CDR3 sequence information. Here we present protocols in detail for CDR-H3 spectratype analysis and HTS of human BCR repertoires.

An activity designed to assist students in comparing the known and suspected risks and benefits involved in taking oral contraceptives (OCs) is presented. It has been used in a college-level health issues class and probably could be used at the secondary level. The activity could function as a catalyst to a discussion of the research findings on OCs or it could follow such a discussion and be used as a type of evaluation. Each student is given a handout containing profiles of 3 women who are trying to decide whether or not to take OCs. The student must evaluate each characteristic in the profile provided here and indicate whether it is a risk or a benefit for the woman in question. The reason(s) for their decision must be listed. After the students have had time to list their individual responses ideas can be shared during a class discussion. At this time the group will most likely discover that certain factors represent both a risk and a benefit. Following the discussion of risks and benefits the class may try to reach a consensus and recommend a decision for each women. The students should be encouraged to explain why certain factors carry more weight than others when making a final decision.