National Knowledge-Driven Management of Obstructive Sleep Apnea-The Swedish Approach

INTRODUCTION

This paper describes the development of "Swedish Guidelines for OSA treatment" and the underlying managed care process. The Apnea Hypopnea Index (AHI) is traditionally used as a single parameter for obstructive sleep apnea (OSA) severity classification, although poorly associated with symptomatology and outcome. We instead implement a novel matrix for shared treatment decisions based on available evidence.

METHODS

A national expert group including medical and dental specialists, nurses, and patient representatives developed the knowledge-driven management model. A Delphi round was performed amongst experts from all Swedish regions (N = 24). Evidence reflecting treatment effects was extracted from systematic reviews, meta-analyses, and randomized clinical trials.

RESULTS

The treatment decision in the process includes a matrix with five categories from a "very weak"" to "very strong" indication to treat, and it includes factors with potential influence on outcome, including (A) OSA-related symptoms, (B) cardiometabolic comorbidities, (C) frequency of respiratory events, and (D) age. OSA-related symptoms indicate a strong incitement to treat, whereas the absence of symptoms, age above 65 years, and no or well-controlled comorbidities indicate a weak treatment indication, irrespective of AHI.

CONCLUSIONS

The novel treatment matrix is based on the effects of treatments rather than the actual frequency of respiratory events during sleep. A nationwide implementation of this matrix is ongoing, and the outcome is monitored in a prospective evaluation by means of the Swedish Sleep Apnea Registry (SESAR).

Interaction of Np(v) with borate in alkaline, dilute-to-concentrated, NaCl and MgCl2 solutions

The formation of sparingly soluble ternary Na/Mg–Np(v)–borate(s) solid phases in alkaline, dilute-to-concentrated, NaCl and MgCl₂ solutions is confirmed by a multimethod experimental approach.

Performance of a new quantitative method for assessing dural ectasia in patients with FBN1 mutations and clinical features of Marfan syndrome

INTRODUCTION

This study presents a comparison of established methods for measuring dural ectasia with a new quantitative method of assessing this clinical feature.

METHODS

Seventeen patients with an identified mutation in FBN1 were examined for dural ectasia. The results were compared with 17 age- and sex-matched controls. Our images were also evaluated using the two methods of quantifying dural ectasia, namely those of Ahn et al. and of Oosterhof et al.

RESULTS

With our method, 80% MFS1 patients and 7% controls fulfilled the criterion for dural ectasia. Using the method of Oosterhof et al., dural ectasia was found in 88% patients with MFS1 and in 47% controls. Using the method of Ahn et al. 76% patients with Marfan syndrome and 29% controls showed dural ectasia.

CONCLUSION

We present a novel quantitative method of evaluating MRT images for dural ectasia, which, in our own patient cohort, performed better than those previously described.

Translocations t(11;18)(q21;q21) and t(14;18)(q32;q21) are the main chromosomal abnormalities involving MLT/MALT1 in MALT lymphomas

The recently discovered MLT/MALT1 gene is fused with the API2 gene in the t(11;18)(q21;q21), which characterizes about one-third of MALT lymphomas. In order to screen for variant translocations and amplifications of MLT/MALT1, we have developed a novel, undirected two-color interphase fluorescence in situ hybridization (FISH) assay with two PAC clones flanking MLT/MALT1. This assay was applied to 108 marginal zone B-cell lymphomas (MZBCLs), including 72 extranodal MALT lymphomas, 17 nodal, and 19 splenic MZBCL. In 19 MALT lymphomas (26%), but in none of the nodal or splenic MZBCL, separated hybridization signals of the MLT/MALT1 flanking probes, were found. Further FISH analyses showed that 12 of these 19 cases displayed the classical t(11;18) and the remaining seven cases revealed the novel t(14;18)(q32;q21), involving the MLT/MALT1 and IGH genes. The frequency at which these translocations occurred varied significantly with the primary location of disease. The t(11;18) was mainly detected in gastrointestinal MALT lymphomas, whereas the t(14;18) occurred in MALT lymphomas of the parotid gland and the conjunctiva. Amplification of MLT/MALT1 was not observed in any of the lymphomas analyzed. We conclude that the translocations t(11;18)(q21;q21) and t(14;18)(q21;q32) represent the main structural aberrations involving MLT/MALT1 in MALT lymphomas, whereas true amplifications of MLT/MALT1 occur rarely in MZBCL.

Chromosomal gains and losses are uncommon in hairy cell leukemia: a study based on comparative genomic hybridization and interphase fluorescence in situ hybridization

In contrast to other subtypes of lymphoproliferative malignancies, the genetic mechanisms underlying the pathogenesis of hairy cell leukemia (HCL) are unknown. We studied densely infiltrated splenic tissue of 14 cases of HCL for the presence of chromosomal gains and losses by comparative genomic hybridization (CGH). Chromosomal imbalances were detected in only four of the 14 cases. Chromosomal gains involved the regions 5q13-q31 (two cases) and 1p32-p36.2 (one case). A loss of the region 11q14-q22 was found in one additional patient. The imbalances affecting the regions 5q and 11q were confirmed by interphase fluorescence in situ hybridization (FISH) using PAC clone 144G9 (5q31) and YAC clones 755B11 (11q22.3-q23.1) and 801E11 (11q22.3-q23.1 spanning the ATM gene) and occurred in 61% to 75% of analyzed nuclei. The latter DNA probes and probes hybridizing to chromosomal regions, which are frequently deleted in other subtypes of non-Hodgkin lymphomas (NHL), namely 9p21/ P16(INK4A), 13q14/D13S25, and 17p13/P53 were subsequently applied to all 14 cases of HCL, but no additional abnormalities were found. We conclude that overrepresentation of chromosome 5 represents a recurrent aberration in HCL and that the commonly overrepresented region resides in 5q13-q31. Chromosomal imbalances including deletions of the tumor suppressor gene loci 9p21/P16(INK4A), 13q14/D13S25, and 17p13/P53 rarely occur in HCL in contrast to some other subtypes of B-cell NHL. The pathogenetic role of 11q/ATM alterations in HCL remains to be determined.

Detection of t(11;18)(q21;q21) by interphase fluorescence in situ hybridization using API2 and MLT specific probes

The translocation of chromosome 11, long arm, region 2, band 1, to chromosome 18, long arm, region 2, band 1 (t(11;18)(q21;q21)) represents a recurrent chromosomal abnormality in extranodal marginal zone B-cell lymphoma (MZBCL) of mucosa-associated lymphoid tissue (MALT) type and leads to a fusion of the apoptosis inhibitor-2 (API2) gene on chromosome 11 and the MALT lymphoma-associated translocation (MLT) gene on chromosome 18. A 2-color fluorescence in situ hybridization (FISH) assay, which can be used for the detection of t(11;18) in interphase nuclei and metaphase chromosomes on fresh and archival tumor tissue, was developed. The P1 artificial chromosome (PAC) clone located immediately telomeric to the MLT gene and the PAC clone spanning the API2 gene were differentially labeled and used to visualize the derivative chromosome 11 resulting from t(11;18), as evident by the overlapping or juxtaposed red and green fluorescent signals. The assay was applied to interphase nuclei of 20 cases with nonmalignant conditions and 122 B-cell non-Hodgkin's lymphomas (NHLs). The latter group comprised 20 cases of nodal follicle center cell lymphoma and diffuse large B-cell NHL, 10 cases of gastric diffuse large B-cell lymphoma, 10 cases of hairy cell leukemia, and 82 cases of MZBCL (41 extranodal from various locations, 19 nodal, and 22 splenic MZBCL) including 35 cases with an abnormal karyotype, 2 of which revealed t(11;18). By interphase FISH, t(11;18) was detected in 8 gastrointestinal low-grade MALT-type lymphomas including the 2 cytogenetically t(11;18)(+) cases. In the 8 t(11;18)(+) cases, the FISH results were confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR) using API2 and MLT specific primers. Our results indicate that t(11;18)(q21;q21) specifically characterizes a subgroup of low-grade MZBCL of the MALT-type and that the FISH assay described here is a highly specific and rapid test for the detection of this translocation.

Analysis of the P53, RB/D13S25, and P16 tumor suppressor genes in marginal zone B-cell lymphoma: An interphase fluorescence in situ hybridization study

The genetic mechanisms underlying the genesis, disease progression, and high-grade transformation of marginal zone B-cell lymphoma (MZBCL) are poorly understood. We analyzed 33 cases of histologically and immunophenotypically well-characterized MZBCL (12 extranodal, 11 nodal, and 10 splenic MZBCL; 27 at primary diagnosis and six during the course of disease) by dual-color interphase fluorescence in situ hybridization (FISH) for deletions of tumor suppressor genes. We investigated loci known to play a role in the genesis or disease progression of other subtypes of lymphoid malignancies, namely the P53 gene (17p13), the retinoblastoma gene (RB, 13q14), the D13S25 locus (13q14), and the P16(INK4A) gene (9p21). Heterozygous deletions of P53 were detected in three out of the 33 cases, including two splenic and one extranodal MZBCL. One of these patients was analyzed at primary diagnosis and two during the course of disease. Heterozygous deletions of the RB gene (nodal MZBCL) and D13S25 (splenic MZBCL) were found in one case each. P16 deletions were not detected in any of our cases. We conclude that deletions of the analyzed tumor suppressor genes are relatively rare in MZBCL, which contrasts with the findings in some other subtypes of NHL.

Genetic abnormalities in marginal zone B-cell lymphoma

Marginal zone B-cell lymphoma (MZBCL) including extranodal mucosa-associated lymphoid tissue (MALT)-type lymphoma, nodal, and splenic MZBCL represents a distinct subtype of B-non-Hodgkin's lymphoma. Recently, important progress in the elucidation of the genetic mechanisms underlying the pathogenesis and disease progression of these lymphomas has been made. The API2 gene, an inhibitor of apoptosis, and the novel MLT gene have been found to be altered by the t(11;18)(q21;21), which represents the most frequent structural chromosomal abnormality in extranodal low-grade MALT lymphoma. Another gene involved in the regulation of apoptosis, the BCL10 gene, has been cloned from a MALT lymphoma cytogenetically characterized by the t(1;14)(p22;q32). Along the same lines, inactivating mutations of the proapoptotic FAS gene have been detected in a relatively high proportion of extranodal MZBCLs. Considering these data and the fact that at least some MALT lymphomas show low levels of apoptosis and seem to escape from FAS-mediated apoptosis one may speculate that abrogation of apoptosis constitutes a central pathogenetic mechanism in the development of these lymphomas. The pathogenetic role of trisomy 3, the most frequent numerical chromosomal change of MZBCL, is not known. The minimal overrepresented region has been delineated to 3q21-23 and 3q25-29 using comparative genomic hybridization. The BCL6 proto-oncogene, located on 3q27, which is rearranged in some MZBCL and a high proportion of large cell B-cell lymphomas with extranodal localization, represents one of the candidate genes residing in these critical regions.

Polysomy 13 with concomitant deletion of 13q13-14 involving the retinoblastoma gene and the D13S25 locus in a case of acute myeloid leukemia

We herein describe a case of acute myeloblastic leukemia (AML), FAB subtype M4, with an unfavorable clinical course and a complex karyotype, including 4-9 copies of chromosome 13. Polysomy 13 was a result of clonal evolution. Fluorescence in situ hybridization (FISH) revealed a cytogenetically unrecognizable deletion within 13q13-14 that included the retinoblastoma gene (RB) and the D13S25 locus in all but one copy of chromosome 13. The only chromosome 13 that did not show a deletion affecting the q13-14 region was translocated to chromosome 7, resulting in a dic(7;13)(q21;p11). In this case, the coexistence of polysomy and a partial deletion within the same chromosome point toward a possible formation of a fusion product with oncogenic potential and its consecutive amplification as a critical alteration in this case.

Genetic abnormalities in marginal zone B-cell lymphoma

Marginal zone B-cell lymphoma (MZBCL) including extranodal mucosa-associated lymphoid tissue (MALT)-type lymphoma, nodal, and splenic MZBCL represents a distinct subtype of B-non-Hodgkin's lymphoma. Recently, important progress in the elucidation of the genetic mechanisms underlying the pathogenesis and disease progression of these lymphomas has been made. The API2 gene, an inhibitor of apoptosis, and the novel MLT gene have been found to be altered by the t(11;18)(q21;21), which represents the most frequent structural chromosomal abnormality in extranodal low-grade MALT lymphoma. Another gene involved in the regulation of apoptosis, the BCL10 gene, has been cloned from a MALT lymphoma cytogenetically characterized by the t(1;14)(p22;q32). Along the same lines, inactivating mutations of the proapoptotic FAS gene have been detected in a relatively high proportion of extranodal MZBCLs. Considering these data and the fact that at least some MALT lymphomas show low levels of apoptosis and seem to escape from FAS-mediated apoptosis one may speculate that abrogation of apoptosis constitutes a central pathogenetic mechanism in the development of these lymphomas. The pathogenetic role of trisomy 3, the most frequent numerical chromosomal change of MZBCL, is not known. The minimal overrepresented region has been delineated to 3q21-23 and 3q25-29 using comparative genomic hybridization. The BCL6 proto-oncogene, located on 3q27, which is rearranged in some MZBCL and a high proportion of large cell B-cell lymphomas with extranodal localization, represents one of the candidate genes residing in these critical regions.