Comfort rules for face masks among healthcare workers during COVID-19 spread.

BACKGROUND: The outbreak of Coronavirus disease 2019 (COVID-19) made imperative the use of protective devices as a source control tool. As there is no definite antiviral treatment and effective vaccine, the only efficient means of protecting and mitigating infectious contagion has been the use of personal protective equipment, especially by healthcare workers. However, masks affect the humidification process of inhaled air, possibly leading to a basal inflammatory state of the upper airways. STUDY DESIGN: This is a single-center observational study conducted at the University Hospital of Catania from April 1, 2020, to June 31, 2020. METHODS: We analyzed the role of protective masks on the elimination of upper airways complaints in healthcare workers of the University Hospital of Catania. We evaluated 277 subjects through a self-administered 17 item questionnaire based on respiratory, work performance and health-related quality of life domains. RESULTS: A higher prevalence of nasal and ocular symptoms, perceived reduced work performance, difficulty in concentrating, and sleep disorders were found. After two weeks adhering to a list of good practices that we recommended, significant reversibility of the symptoms investigated and work performance enhancement were observed. CONCLUSIONS: Despite clinical complaints related to personal protective equipment, effective amelioration through usage rules is easily obtained. Given the essential use of protective masks, healthcare workers have to adhere to appropriate work and safety prevention rules.

Variations of thoracoabdominal volumes after lung transplantation measured by opto-electronic plethysmography.

BACKGROUND: Lung function after lung transplantation (LTx) has been widely studied. On the contrary, the thoracoabdominal volume rearrangement after LTx has yet to be investigated. METHODS: Patients with cystic fibrosis and listed for double LTx at our institution were enrolled for the prospective study to explore the effects of LTx on the rearrangement of respiratory volumes in patients affected by cystic fibrosis, by utilizing the opto-electronic plethysmography (OEP), a noninvasive method to study the volume and motion of the human trunk. Rib cage and abdominal volumes were tested with OEP (OEP system, BTS, Milano, Italy). RESULTS: Eight patients were enrolled (male-to-female ratio: 1:3; mean age 29.3 ± 7.8 years). After LTx the volume changes analyzed with OEP revealed a significant decrease of the total lung capacity (TLC) as well as the functional residual capacity and residual volume when the chest wall volume was considered. Dividing the whole respiratory volume in the three compartments showed different trends. CONCLUSIONS: We consider OEP a particularly useful device in patients with severe respiratory disease, in that it allows a noninvasive estimate of the volume change of the chest wall. This study demonstrates a significant reduction of thoracoabdominal volumes in patients affected by cystic fibrosis treated with bilateral LTx. Abdomen and upper rib cage were congruent with the volume reduction, while the lower rib cage showed an opposite tendency.

Promoter analysis of TFPT (FB1), a molecular partner of TCF3 (E2A) in childhood acute lymphoblastic leukemia.

We previously identified the TFPT (FB1) gene as a molecular partner of TCF3 (E2A) in childhood pre-B cell acute lymphoblastic leukemia (ALL). TFPT (FB1) alignment in man, mouse and rat displays a very high degree of identity, indicating that it may play a basic role in mammalian cells. To get insights into this role, we have identified and studied the TFPT (FB1) promoter and its responsiveness to hematopoietic transcriptional factors. We found that the TFPT (FB1) 5' flanking sequence displays the features of a TATA-less promoter with weak homology to Inr (Initiator) elements. Starvation experiments suggested that TFPT (FB1) expression might be constitutive. Nevertheless, the TFPT (FB1) promoter, tested by transactivation assays, was found to be responsive to Ikaros 2 and, mainly, to PU.1, a transcription factor belonging to the Ets family. Thus, these hematopoietic factors, known to play critical roles during the early stages of B cell differentiation and to be involved in leukemia, might modulate TFPT (FB1) expression during hematopoiesis and/or leukemia development.

Identification of a novel molecular partner of the E2A gene in childhood leukemia.

The 'promiscuous' E2A gene, at 19p13.3, is fused with two different molecular partners, PBX1 and HLF, following two chromosome translocations recurrent in childhood pre-B ALL. We have identified a novel gene, FB1, by virtue of its fusion with E2A and by a combination of molecular techniques. FB1 was localized on 19q13.4, suggesting that the novel chimera originated by a cryptic rearrangement of chromosome 19. Two FB1 transcripts, of 1.2 kb and 1.1 kb, are differentially expressed at low level in a variety of human tissues, including hemopoietic cell lines from different lineages. Accordingly, FB1 cDNA displays high homology with a number of cDNA clones from different human tissues. High homology was found also with cDNA clones from mouse and rat, suggesting that the sequence might be conserved at least among mammals. The function of the putative FB1 protein, however, is currently unknown as database sequence comparisons have failed to reveal strong homology with known proteins. The E2A/FB1 fusion appears to be a recurrent feature of pre-B ALLs, suggesting that it might have a role in the development and/or progression of leukemogenesis.

Identification of new partner chromosomes involved in fusions with the ETV6 (TEL) gene in hematologic malignancies.

Several partner genes on different chromosomes have been reported to be fused with the ETV6 gene (located in chromosome band 12p13), with different breakpoints and different frequencies, in various hematologic malignancies, particularly acute myeloid and lymphoid leukemias and myelodysplastic syndromes. By using FISH and molecular analyses, we have analyzed five different pediatric and adult patients carrying cytogenetic abnormalities involving 12p13. Our findings demonstrate that ETV6 was rearranged in all the cases analyzed. In particular, ETV6 was disrupted by translocations with chromosomal bands 7q22, 7q36, 9q11, and 13q12, not previously described as partners of ETV6 in translocations, thus extending its promiscuity in rearranging with different partner genes.

Unbalanced t(3;12) in a case of juvenile myelomonocytic leukemia (JMML) results in partial trisomy of 3q as defined by FISH.

Juvenile myelomonocytic leukemia (JMML) is a rare disorder of early childhood, to which no recurrent chromosome rearrangement has been yet associated. We report a case where leukemic cells harbored a 46,XX,der(12)t(3;12) (q21 approximately 22;p13.33) karyotype, resulting in partial trisomy of 3q. The origin of chromosome material translocated to chromosome 12 was assessed by chromosome painting using a whole chromosome 3-specific probe. The breakpoint regions were defined by FISH using YAC probes from 3q and 12p chromosomal regions. Interestingly, partial trisomy of 3q has been detected in a previously reported JMML case, consequent to the presence of a der(15)t(3;15)(q13.1;q26). The involvement of a similar chromosome 3 rearrangement in these two JMML cases suggests the hypothesis that either the resulting duplication of some gene/s on 3q or the loss of heterozygosity (LOH) of some gene/s on 3p may be involved in one of the steps leading to JMML. On the other hand, it cannot be ruled out that the relevant mutation in our case might be consequent to the particular breakpoints at bands 3q21 approximately 22 and 12p13.3, that may alter the structure and/or expression of the involved gene/s.

EVI-1 gene expression in myeloid clonogenic cells from juvenile myelomonocytic leukemia (JMML).

Juvenile myelomonocytic leukemia (JMML) is a rare myeloproliferative disease of early childhood, that is peculiarly characterized by the ability of bone marrow progenitors to spontaneously proliferate in vitro, giving rise to granulocyte-macrophage colonies. Although the genetic alteration/s leading to JMML development are still unclear, several lines of evidence indicate that the JMML initiating cell (JMML-IC) may belong to the pool of early stem-like hematopoietic progenitors. Increased EVI-1 gene expression has been detected in a number of myeloproliferative disorders including MDS, AML, blast crisis of CML, and more recently in the peripheral blood of some JMML patients. In order to investigate the nature of the cells expressing EVI-1 in JMML patients, we analyzed its expression in CFU-GM obtained from bone marrow and peripheral blood as well as from highly purified CD34+ progenitors. Normal CFU-GM obtained both from bone marrow mononuclear cells and from highly purified CD34+ cells were also analyzed. Overall, our results suggest that the EVI-1 gene may be normally expressed in early hematopoietic progenitor cells and that in JMML patients an expansion of the EVI-1 positive cell population can be revealed within the clonogenic progenitor pool.

Reverse transcriptase/polymerase chain reaction follow-up and minimal residual disease detection in t(1;19)-positive acute lymphoblastic leukaemia.

The t(1;19) is the most frequent recurring chromosomal translocation in childhood acute lymphoblastic leukaemia (ALL). In most cases typical chimaeric E21-PBX1 transcripts are expressed as a consequence of this rearrangement, allowing the molecular detection of the t(1;19) at the RNA level. This translocations has been associated with a poor clinical outcome, although intensified chemotherapy has been reported to nullify its adverse prognostic impact. We therefore used reverse transcriptase/polymerase chain reaction (RT-PCR) to detect residual leukaemic cells at successive times during treatment and to monitor the response to chemotherapy in six t(1;19)-positive ALL pediatric patients. Five of these patients rapidly achieved molecular remission and no evidence of minimal residual disease (MRD) was found in the remission bone marrows beyond the third month of treatment. One patient still displayed residual leukaemic cells at the end of therapy, although she has been in continuous complete clinical remission (CCR) for 84 months. However, this patient is peculiar in our series in that two different types of chimaeric E2A-PBX1 transcripts were expressed in her leukaemic cells, only one being detectable in remission.

Constitutive expression of GATA-1, EPOR, alpha-globin, and gamma-globin genes in myeloid clonogenic cells from juvenile chronic myelocytic leukemia.

Juvenile chronic myelocytic leukemia (JCML) is a rare disorder of early childhood. Characteristic of JCML are the progressive appearance of high levels of fetal hemoglobin (HbF), reflecting a true reversion to a fetal type of erythropoiesis, and the presence of colony-forming cells able to grow in vitro spontaneously in the absence of growth factors. To better understand the relationship between the erythroid abnormalities and the leukemic process, we analyzed the expression pattern of specific genes related to erythroid differentiation--GATA-1, EPOR, alpha-globin, beta-globin, and gamma-globin genes--in JCML peripheral blood (PB) cells and in vitro-derived colonies. Northern blot analysis of PB cells from five JCML patients indicated levels of GATA-1 transcripts much higher than those usually found in other types of leukemic cells, and S1 nuclease protection assay detected significantly increased expression of gamma-globin mRNA. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of single granulocyte-macrophage colony-forming unit (CFU-GM) colonies, obtained in vitro in the absence of added growth factors from four JCML patients, detected GATA-1, EPOR, and globin (alpha and gamma) transcripts in most of the colonies tested, in contrast with control CFU-GM from normal bone marrow, which were positive only for GATA-1. Single JCML colonies were tested for the presence of two different transcripts; whereas alpha- and gamma-globin genes appeared mostly coexpressed, beta-globin mRNA was detected only in a minority of the gamma-globin-positive colonies, indicating that the leukemic pattern of hemoglobin synthesis is mainly fetal. In addition, the leukemic cells occurring during blast crisis of one of our patients displayed the typical features of a stem cell leukemia (CD34+, CD19-, CD2-, myeloperoxidase-). In this sorted CD34+ population, we detected the presence of a marker chromosome, der(12)t(3;12), previously identified in bone marrow cells at diagnosis and an expression pattern superimposable to that of the JCML colonies, consistently displaying a high gamma-globin:beta-globin mRNA ratio. The expression of erythroid markers within populations of leukemic cells, both in vivo and in vitro, supports the hypothesis that abnormal JCML erythroid cells may originate from the same mutated progenitor that sustains the growth of the leukemic cells.

Molecular variants of the 1;19 chromosomal translocation in pediatric acute lymphoblastic leukemia (ALL).

The t(1;19)(q23;p13), a non-random chromosome rearrangement associated with childhood pre-B acute lymphoblastic leukemia (ALL), results at molecular level in the hybrid E2A-PBX1 gene. This gene is expressed in a typical set of fusion transcripts and oncogenic chimeric proteins. However, the occurrence of t(1;19) molecular variants has been recently suggested. In an attempt to identify these variants, we analyzed 25 pediatric cases of pre-B cIg+ cell ALL. We used Southern blot analysis to detect E2A gene rearrangements and RT-PCR to detect chimeric E2A-pbx1 transcripts. In addition to seven cases with the molecular pattern usually associated with the t(1;19), we identified three molecular variants. In one case, a variant E2A-pbx1 transcript showed 27 additional base pairs inserted in frame at the junction site. In two cases, Southern blot evidenced the expected E2A gene rearrangements. However, extensive RT-PCR analysis failed to detect any E2A-pbx1 transcript. These findings led us to hypothesize that a gene other than PBX1 might be involved in these 1;19 variant translocations.

Monosomy 7 and unbalanced t(1;7) in an adolescent boy with myelodysplastic syndrome.

Monosomy 7 occurs in approximately 5% of cases of myelodysplastic syndrome (MDS) in children and is associated with a poor prognosis. The unbalanced translocation t(1;7) is common in therapy-related MDS in adults but is extremely rare in children, with only three cases reported to date. We describe a pediatric case of MDS with the unusual combination of monosomy 7 and unbalanced t(1;7) in two distinct clones. Both clones were detected at diagnosis and have persisted throughout the course of MDS in this patient, a 16-year-old boy without prior exposure to known mutagens. Because of recurrent severe infections associated with neutropenia, he was treated with recombinant human granulocyte-macrophage colony-stimulating factor. This therapy improved the neutrophil count but did not alter the karyotype or the progression of disease.

Different molecular consequences of the 1;19 chromosomal translocation in childhood B-cell precursor acute lymphoblastic leukemia.

The prognostically important 1;19 chromosomal translocation can alter the E2A gene on chromosome 19p13 in childhood B-cell precursor acute lymphoblastic leukemia (ALL), leading to formation of a fusion gene (E2A-PBX1) that encodes a hybrid transcription factor with oncogenic potential. It is not known whether this molecular alteration is a uniform consequence of the t(1;19) or is restricted to translocation events within specific immunologic subtypes of the disease. Therefore, we studied leukemic cells from 25 cases of B-cell precursor ALL, with or without evidence of cytoplasmic Ig mu heavy chains (cIg); 17 cases had the t(1;19) by cytogenetic analysis. Leukemic cell DNA samples were analyzed by Southern blotting to detect alterations within the E2A genomic locus; a polymerase chain reaction assay was used to identify expression of chimeric E2A-pbx1 transcripts in leukemic cell RNA; and immunoblotting with anti-Pbx1 antibodies was used to detect hybrid E2A-Pbx1 proteins. Of 11 cases of cIg+ ALL with the t(1;19), 10 had E2A-pbx1 chimeric transcripts with identical junctions and a characteristic set of E2A-Pbx1 hybrid proteins. Each of these cases had E2A gene rearrangements, including the one in which fusion transcripts were not detected. By contrast, none of the six cases of t(1;19)-positive, cIg- ALL had evidence of rearranged E2A genomic restriction fragments, detectable E2A-pbx1 chimeric transcripts, or hybrid E2A-Pbx1 proteins. Typical chimeric E2A-pbx1 transcripts and proteins were detected in one of eight cIg+ leukemias in which the t(1;19) was not identified by cytogenetic analysis, emphasizing the increased sensitivity of molecular analysis for detection of this abnormality. We conclude that the molecular breakpoints in cases of cIg- B-cell precursor ALL with the t(1;19) differ from those in cIg+ cases with this translocation. Leukemias that express hybrid oncoproteins such as E2A-Pbx1 or Bcr-Abl have had a poor prognosis in most studies. Thus, molecular techniques to detect fusion genes and their aberrant products should allow more timely and appropriate treatment of these aggressive subtypes of the disease.

Trisomy 21 as the sole acquired chromosomal abnormality in children with acute lymphoblastic leukemia.

Most studies of cytogenetic abnormalities in leukemia patients have focused on structural chromosomal rearrangements. Less attention has been paid to the role of single numerical abnormalities in the complex mechanisms of leukemia pathogenesis. We therefore studied 11 cases of acute lymphoblastic leukemia (ALL) with trisomy 21 as the sole chromosomal abnormality, representing 1.8% of 601 completely banded cases of ALL seen during a 10-year period. Bone marrow cells from all but one of these cases also had normal karyotypes, representing 8 to 77% of the completely analyzed metaphases. Each of the five cases tested lacked evidence of trisomy 21 mosaicism of constitutional origin in peripheral blood samples. The presenting features of these five girls and six boys were heterogeneous but tended to reflect lower-risk ALL: median age, 3.3 years (range 1-18 years), median leukocyte count, 11.6 x 10(9)/l (range 1.8-82 x 10(9)/l), white race, and a B-cell precursor immunophenotype. Complete remissions were readily induced in all 11 patients. With follow-up ranging from 1+ months to 6.4+ years, the only relapses have been extramedullary (testis and central nervous system) in two patients, both of whom have since achieved second remissions of greater than 76 and greater than 65 months. Trisomy 21 as the sole chromosomal abnormality in childhood ALL appears related to favorable presenting risk features and may represent a good prognosis subset within the group of patients with 47-50 chromosomes.

New recurring chromosomal translocations in childhood acute lymphoblastic leukemia.

We identified seven new recurring translocations among 483 cases of acute lymphoblastic leukemia (ALL) with adequate chromosome banding studies. Four were apparently balanced [t(1;3)(p34;p21), t(7;9)(p15;p23-p24), t(12;13)(p13;q14), t(17;19)(q22;p13)], while three were unbalanced with the formation of a dicentric chromosome [dic(7;9)(p13;p11), dic(7;12)(p11;p12), and dic(12;17)(p11;p11-p12)]. One translocation was observed in five cases, two in four cases, and the remaining four in two cases each. The modal chromosome numbers in these 21 cases were 45 (n = 11), 46 (n = 8), and 47 (n = 2). Eight of the 11 cases with a dicentric chromosome had a modal number of 45. Only a single translocation was found in 14 cases (67%), representing the sole structural abnormality in six cases. In three of the seven translocation subgroups, the blast cells were consistently of B lineage (pre-B, early pre-B, or both); in all others, they represented both the B and T lineages. The small size of these subgroups prevented definitive clinical correlations, although it may be important that two of the four cases with a t(17;19) and an early pre-B-cell immunophenotype had disseminated intravascular coagulation, an event usually observed in acute promyelocytic leukemia or T-cell ALL. These findings add substantially to the existing list of nonrandom chromosomal translocations in childhood ALL and may help to explain the genetic alterations leading to the loss of normal growth control mechanisms in this disease.

Double minute chromosomes and a homogeneously staining chromosome region in C3H10T1/2 murine cells transformed "in vitro" by proton radiation.

Four foci (type II or type III) of transformed cells, isolated from the murine line C3H10T1/2 after exposure to proton radiations, were expanded and cytogenetically examined. While the overall numerical chromosome distributions were similar, there were some differences between the various cell lines with regard to the presence and frequency of specific-marker chromosomes and to the colony-forming efficiency in soft-agarose medium. No association between any of these markers and the transformed phenotype could be established. However, in the line F4, derived from a type II focus, numerous double-minute chromosomes (DM) were observed after passage 22, and the phenomenon became more pronounced in the subclone C2. The finding of DMs in radiation-transformed cells is unusual. The DMs were observed in long-term subcultures, and in one of them they were partially replaced by a homogeneously staining chromosome region (HSR). DNAs from transformed cells of the line F4 and subclone C2 was digested with restriction enzymes and analyzed by Southern blotting with probes for seven oncogenes commonly amplified in cancer cells (c-myc, N-myc, N-ras, Ki-ras, Ha-ras, c-myb, c-abl) and with probes for the mouse MHC class I region. None of the regions tested was structurally altered or amplified in these transformed cells. The origin of the genetic material carried by DMs or homogeneously staining intrachromosomal regions (HSR) in cells of the line F4 and subclone C2, where it is believed to provide a selective advantage for in vitro growth, remains unknown.

Sister chromatid exchange in methotrexate resistant and sensitive C3H10T1/2 mouse cells.

Sister chromatid exchange (SCE) induction by methotrexate (MTX) was analyzed in C3H10T1/2 clone 8 mouse cells and in two MTX-resistant subclones with numerous double minute chromosomes (DM) present in the majority of cells. Significantly higher SCE levels were found, as expected, in sensitive cells after treatments with 10(-2) or 10(-5) M MTX but not in resistant cells permanently growing in the presence of a high concentration of MTX (2 x 10(-3) M) and characterized by a markedly lower cell cycle replication index (R.I.), i.e. in conditions that are known to otherwise favour SCE induction. These observations suggest, for the MTX-resistant cells under study, the existence of conditions limiting SCE formation.

Sister chromatid exchange and proliferation pattern in stimulated lymphocytes of cutaneous malignant melanoma patients.

Sister chromatid exchange (SCE) and the proliferative pattern of phytohemagglutinin-stimulated lymphocytes were examined in 36 nonfamilial cutaneous malignant melanoma (CMM) patients. One close relative of each of 27 CMM patients was also examined. All the patients had undergone surgical treatment for the neoplasm, but had received no chemotherapy or radiotherapy. The SCE rates were found to be higher and more variable in a significant fraction of CMM patients, and in relatively fewer unaffected relatives, which is in contrast to findings in unrelated subjects taken as controls. Also, variable and higher proportions of cells in metaphase of the first cell cycle (M1), after 72-hr culture in the presence of bromodeoxyuridine, were more often found among the CMM patients than in the controls; however, no effect of clinical progression of the neoplastic disease on SCE rates or on the lymphoproliferative pattern was observed. The present study indicates heterogeneity among subjects who develop CMM and suggests that the peculiarities of SCE rates and of the lymphoproliferative patterns observed in some of the CMM patients and in a few of their close relatives may be connected with the mechanism of onset of the neoplasm.

Distribution and clustering of two highly repeated sequences in the A and B chromosomes of maize.

Clones from a family of highly repeated sequences present in a heterochromatin rich maize line have been characterized by sequencing and chromosome location. The repeats differ from each other in length and degree of sequence homology, and show areas rich in purine and pyrimidine. In "situ" hybridization experiments indicate that the repeats are mainly located in the knob heterochromatin of the A chromosomes and the centromeric heterochromatin of the B chromosome. However, in addition to previously published data, some copies are also distributed in euchromatic regions of the A chromosomes and in the distal heterochromatic block of the B chromosome. The results are discussed in relation to the centromeric activity of maize heterochromatin.