Catecholaminergic Crisis After a Bleeding Complication of COVID-19 Infection: A Case Report.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presents in some cases with hemostatic and thrombotic complications. Pheochromocytomas are unusual, though potentially lethal tumors. Herein we describe the first case of hemorrhage in a pheochromocytoma related to SARS-CoV-2 infection. A 62-year-old man consulted for syncope, fever, and palpitations. He was diagnosed with SARS-CoV-2 pneumonia and presented with a hemorrhage in a previously unknown adrenal mass, which resulted in a catecholaminergic crisis. Medical treatment and surgery were required for symptom control and stabilization. We hereby alert clinicians to watch for additional/unreported clinical manifestations in COVID-19 infection.

Insertions of mitochondrial DNA into the nucleus-effects and role in cell evolution.

We review the insertion of mitochondrial DNA (mtDNA) fragments into nuclear DNA (NUMTS) as a general and ongoing process that has occurred many times during genome evolution. Fragments of mtDNA are generated during the lifetime of organisms in both somatic and germinal cells, by the production of reactive oxygen species in the mitochondria. The fragments are inserted into the nucleus during the double-strand breaks repair via the non-homologous end-joining machinery, followed by genomic instability, giving rise to the high variability observed in NUMT patterns among species, populations, or genotypes. Some de novo produced mtDNA insertions show harmful effects, being involved in human diseases, carcinogenesis, and ageing. NUMT generation is a non-stop process overpassing the Mendelian transmission. This parasitic property ensures their survival even against their harmful effects. The accumulation of mtDNA fragments mainly at pericentromeric and subtelomeric regions is important to understand the transmission and integration of NUMTs into the genomes. The possible effect of female meiotic drive for mtDNA insertions at centromeres remains to be studied. In spite of the harmful feature of NUMTs, they are important in cell evolution, representing a major source of genomic variation.

[Use of glutamine in total parenteral nutrition of bone marrow transplant patients]. / Uso de la glutamina en la nutricion parenteral total de pacientes sometidos a trasplante de médula ósea.

UNLABELLED: Glutamine is an essential amino acid for nucleotide synthesis and an important energy resource for cellular division. There is contradictory evidence about its benefits as part of parenteral nutrition. More than 75% of bone marrow transplant patients (BMTP) have, during their evolution, digestive tract complications limiting enteral nutrition, for this reason, sometimes total parenteral nutrition (TPN) is required. OBJECTIVE: Our aim was to analyze the relation between the use of glutamine in TPN of BMTP, and the evolution of clinical acute complications as mucositis, graft versus host disease (GVHD) and infections days of stay and days of TPN. MATERIALS AND METHODS: observational retrospective study. All BMTP with total parenteral nutrition during the period 2007-2013 were included. We analyzed days of stay, days of nutrition, glutamine use and acute complications. Results were analyzed in SPSS 15.0. RESULTS: 73 BMTP were divided in two comparable groups depending on glutamine use. The mean age was 36,96 ± 12,89 years. 47,9% of patients received glutamine in TPN. Patients who received glutamine had a mean stay of 31,49±7,41 days with 14,11±5,87 days of TPN compared with the non-glutamine group with 32,16±7,99 and 15,50±7,71 days respectively (p=0,71 y 0,39). Mucositis lasted 12,23±5,66 days in the glutamine group, and 15,50±7,71 days in the non-glutamine group (p=0,042). Severe grades of GVHD (II,III) was observed in 20,6% of the non glutamine group compared with the 13,7% of the other group (p=0,636). In patients with glutamine suplementation, mucositis last 12,23±5,66 days compared with 15,50±7,71 days in the non-glutamine group (p=0,042).13,7% of all patients suffered infections while receiving TPN with glutamine compared with 16,4% in patients who did not receive glutamine (p=0,700). CONCLUSION: In our group, a statistically significant reduction in the duration of mucositis was observed in patients who received parenteral glutamine.

La glutamina es un amioácido esencial para la síntesis de nucleótidos y una fuente de energía para la replicación celular, existe evidencia contradictoria respecto a los beneficios de su administración como parte de la nutrición parenteral en pacientes sometidos a trasplante de médula ósea (TMO). Más del 75% de los pacientes sometidos a trasplante de precursores hematopoyéticos, presentan durante su evolución complicaciones que comprometen el tracto digestivo, principalmente mucositis, limitando la ingesta oral, de allí la necesidad del uso de nutrición parenteral total (NPT) en estos casos. Objetivo: Analizar la relación entre uso de glutamina en la NPT de TMO y la evolución de complicaciones agudas como mucositis, EICH e infecciones, así como la estancia hospitalaria y los días de nutrición parenteral total. Material y métodos: Estudio observacional retrospectivo. Se incluyeron la totalidad de TMO con NPT entre 2007 y 2013 en nuestro hospital. Se analizaron días de hospitalización, días de soporte nutricional, uso de glutamina y complicaciones agudas. Los resultados se analizaron con el programa SPSS 15.0. Resultados: Se incluyeron 73 pacientes trasplantados, se dividieron en dos grupos según el aporte de glutamina siendo ambos grupos comparables entre sí. La edad media fue de 36,96±12,89 años. El 47,9% de los pacientes estudiados recibió suplemento de glutamina en la NPT. Los pacientes que recibieron glutamina tuvieron una estancia media de 31,49±7,41 días con 14,11±5,87 días de NPT en comparación a los que no recibieron glutamina con 32,16±7,99 y 15,50±7,71 días respectivamente (p=0,71 y 0,39). La duración de la mucositis en los pacientes que recibieron glutamina fue de 12,23±5,66 días comparado con 15,50±7,71 días en los que no recibieron glutamina (p=0,042).Se observaron grados severos de EICH (II, III) en un 20,6% de los pacientes sin glutamina en comparación al 13,7% en los que la recibieron (p=0,636). . Del total de los pacientes estudiados, el 13,7% sufrieron complicaciones infecciosas mientras recibían NPT con glutamina, comparado con 16,4% en pacientes que no recibieron (p=0,700).Conclusiones: En nuestra serie, se observó una reducción estadísticamente significativa en la duración de la mucositis en pacientes que recibieron NPT con glutamina.

Rye B chromosomes influence the dynamics of histone H3 methylation during microgametogenesis.

We have studied the trimethylation dynamics of lysines 4 and 27 of histone H3 in rye with and without B chromosomes (Bs) in root tip mitosis, meiosis, and pollen grain mitosis by immunostaining. In root meristems, H3K4me3 immunolabeling was homogeneous along the chromosome arms of the normal complement (As), with the exception of the pericentromeric and subtelomeric regions which were unlabeled. On the contrary, a signal was observed on the long arm of the B chromosome, in the region where most of the B-specific repeats are located. H3K27me3 immunosignals were observed on the subtelomeric heterochromatic region of the As and the Bs and some interstitial bands of the As. Thus, the terminal region of the Bs showed both signals, whereas the subtelomeric region of the As showed H3K27me3 immunosignals only. During meiosis and first pollen grain mitosis, the immunosignals were observed distributed as in the root tip mitosis in plants with or without Bs. However, we observed remarkable changes in the immunolabeling patterns during the second pollen grain mitosis between 0B and +B plants. In 0B plants, H3K4me3 immunosignals were similarly distributed in the vegetative and generative nuclei. In B-carrying plants, the vegetative nucleus showed a lighter signal than the generative one. In 0B plants, all nuclei of the microgametophyte showed H3K27me3 immunosignals. In B-carrying plants, the generative nucleus and, correspondingly, the second metaphase, anaphase, and sperm nuclei did not show any signal. When the Bs were lost as micronuclei, they did not show any H3K4me3 or H3K27me3 signal. Most remarkably, Bs are able to change the pattern of H3 methylation on K4 and K27 during the second pollen mitosis, resulting in differently labeled sperm nuclei in 0 and +B plants.

Nondisjunction in favor of a chromosome: the mechanism of rye B chromosome drive during pollen mitosis.

B chromosomes (Bs) are supernumerary components of the genome and do not confer any advantages on the organisms that harbor them. The maintenance of Bs in natural populations is possible by their transmission at higher than Mendelian frequencies. Although drive is the key for understanding B chromosomes, the mechanism is largely unknown. We provide direct insights into the cellular mechanism of B chromosome drive in the male gametophyte of rye (Secale cereale). We found that nondisjunction of Bs is accompanied by centromere activity and is likely caused by extended cohesion of the B sister chromatids. The B centromere originated from an A centromere, which accumulated B-specific repeats and rearrangements. Because of unequal spindle formation at the first pollen mitosis, nondisjoined B chromatids preferentially become located toward the generative pole. The failure to resolve pericentromeric cohesion is under the control of the B-specific nondisjunction control region. Hence, a combination of nondisjunction and unequal spindle formation at first pollen mitosis results in the accumulation of Bs in the generative nucleus and therefore ensures their transmission at a higher than expected rate to the next generation.

Painting the rye genome with genome-specific sequences.

We used rye-specific repetitive DNA sequences in fluorescence in situ hybridization (FISH) to paint the rye genome and to identify rye DNA in a wheat background. A 592 bp fragment from the rye-specific dispersed repetitive family R173 (named UCM600) was cloned and used as a FISH probe. UCM600 is dispersed over the seven rye chromosomes, being absent from the pericentromeric and subtelomeric regions. A similar pattern of distribution was also observed on the rye B chromosomes, but with weaker signals. The FISH hybridization patterns using UCM600 as probe were comparable with those obtained with the genomic in situ hybridization (GISH) procedure. There were, however, sharper signals and less background with FISH. UCM600 was combined with the rye-specific sequences Bilby and pSc200 to obtain a more complete painting. With these probes, the rye chromosomes were labeled with distinctive patterns; thus, allowing the rye cultivar 'Imperial' to be karyotyped. It was also possible to distinguish rye chromosomes in triticale and alien rye chromatin in wheat-rye addition and translocation lines. The distribution of UCM600 was similar in cultivated rye and in the wild Secale species Secale vavilovii Grossh., Secale sylvestre Host, and Secale africanum Stapf. Thus, UCM600 can be used to detect Secale DNA introgressed from wild species in a wheat background.

Mitochondrial DNA sequences are present inside nuclear DNA in rat tissues and increase with age.

Mitochondrial DNA (mtDNA) mutations increase with age. However, the number of cells with predominantly mutated mtDNA is small in old animals. Here a new hypothesis is proposed: mtDNA fragments may insert into nuclear DNA contributing to aging and related diseases by alterations in the nucleus. Real-time PCR quantification shows that sequences of cytochrome oxidase III and 16S rRNA from mtDNA are present in highly purified nuclei from liver and brain in young and old rats. The sequences of these insertions revealed that they contain single nucleotide polymorphisms identical to those present in mtDNA of the same animal. Interestingly, the amount of mitochondrial sequences in nuclear DNA increases with age in both tissues. In situ hybridization of mtDNA to nuclear DNA confirms the presence of mtDNA sequences inside nuclear DNA in rat hepatocytes. Bone marrow metaphase cells from both young and old rats show mtDNA at centromeric regions in 20 out of the 2n=40 chromosomes. Consequently, mitochondria can be a major trigger of aging but the final target could also be the nucleus.

Chromosome instabilities and programmed cell death in tapetal cells of maize with B chromosomes and effects on pollen viability.

B chromosomes (B's), knobbed chromosomes, and chromosome 6 (NOR) of maize undergo nondisjunction and micronucleus formation in binucleate tapetal cells. These chromosome instabilities are regular events in the program of tapetal cell death, but the B's strongly increase A chromosome instability. We studied 1B and 0B plants belonging to selected lines for high or low B transmission rate and their F1 hybrids. These lines are characterized by meiotic conservation or loss of B chromosomes, respectively. The female B transmission (fBtl) allele(s) for low B transmission is dominant, inducing micronucleus formation and B nondisjunction. We hypothesize that the fBtl allele(s) induces knob instability. This instability would be sufficient to produce B loss in both meiocytes and binucleate tapetal cells. B instability could, in turn, produce instabilities in all chromosomes of maize complement. To establish whether the chromosomal instabilities are related to the tapetal programmed cell death (PCD) process, we applied the TUNEL technique. PCD, estimated as the frequency of binucleate tapetal cells with TUNEL label, was significantly correlated with the formation of micronuclei and the frequency of pollen abortion. It can be concluded that the observed chromosome instabilities are important to the PCD process and to the development of microspores to form viable pollen grains.

Rye terminal neocentromeres: characterisation of the underlying DNA and chromatin structure.

We have studied rye plants with neocentromeres on the terminal regions of the chromosomes. These neocentromeres only appear in meiosis, they are active together with the normal centromere and move the chromosomal arms polewards from prometaphase to anaphase at both the first and second meiotic divisions. All chromosomes of the normal set may show neocentric activity, but chromosomal arms with terminal heterochromatic blocks, as assessed by C-banding, are significantly more susceptible than those that do not have them. At least three repetitive sequences underlie the neocentromeres: pSc34, pSc74 and pSc200. These sequences are not detectable in B chromosomes, which never showed neocentric activity. Fluorescence in situ hybridisation with these sequences used as probes revealed elongated chromatin extensions on the neocentromeres that have not been observed using other staining techniques. These extensions were never observed in control plants. They suggest a modified chromatin structure, which might be responsible for the interaction with proteins involved in chromosomal movement on the spindle.

Characterization of the constriction with neocentric activity of 5RL chromosome in wheat.

In wheat-5RL monotelosomic and ditelosomic addition lines, a proximal constriction located on the long arm of rye chromosome 5R shows neocentric activity at metaphase I of meiosis. In some pollen mother cells this region is unusually stretched, acquires kinetic activity and co-orients with the true centromeres. In the work described here we characterized the putative neocentric constriction of 5RL using various approaches. Fluorescence in situ hybridization (FISH) revealed that the rye subtelomeric repetitive DNA sequence pSc119.2 is a constituent of the 5RL constriction. This FISH site corresponds with a heterochromatic C-band in normal rye. Other subtelomeric (pSc34, pSc74, pSc200), centromeric (CCS1, Bilby) and Arabidopsis-type telomeric sequences produce no detectable hybridization signal on the constriction. Immunolocalization with anti-alpha-tubulin antibodies showed that microtubules are bound to the constriction in a similar way to their binding to true centromeres. Silver staining demonstrated that proteins are accumulated at the constriction, the signal being more prominent than that observed at the centromere and telomeres of 5RL. The frequency of neocentric activity in different plants varied dramatically in different generations and in siblings grown in different years, suggesting that activation of the neocentric site is dependent on internal features and environmental conditions.

Poder bacteriostático in vitro de piperacilina sódica frente a Pseudomonas / In vitro bacteriostatic activity of sodic piperacillin against Pseudomonas

Se tipificaron 122 cepas de Pseudomonas aisladass de procesos patológicos variados, y se estudió la actividad in vitro de Piperacilina por discos y CIM, en forma conjunta con otras dos penicilinas semisintéticas, Carbenicilina y Mezlocilina y dos aminoglucósidos, Amicacina y Gentamicina. Las cepas aisladas correspondieron a: P. aeruginosa 116, P. cepacia 3, P. fluorecens 1 y P. putida 2. Se comprobó que 110 cepas de P. aeruginosa, 1 de P. cepacia y 1 de P. fluorescens, fueron sensibles a Piperacilina, estando estas sensibilidades por encima de las otras penicilinas estudiadas. Las cifras obtenidas con los aminoglucósidos ensayados, son similares para P. aeruginosa. Con respecto a CIM50 y CIM90 los resultados alcanzados con Piperacilina y relacionados con las dos penicilinas semisintéticas estudiadas, están muy alejados de los valores mínimos de sensibilidad, habiéndose observado, en relación a los aminoglucósidos, que si éstos no llegan al valor mínimo de sensibilidad, Piperacilina mantiene sus cifras por encima de los mismos, lo cual resulta importante desde el punto de vista terapéutico

Poder bacteriostático in vitro de piperacilina sódica frente a Pseudomonas / In vitro bacteriostatic activity of sodic piperacillin against Pseudomonas

Se tipificaron 122 cepas de Pseudomonas aisladass de procesos patológicos variados, y se estudió la actividad in vitro de Piperacilina por discos y CIM, en forma conjunta con otras dos penicilinas semisintéticas, Carbenicilina y Mezlocilina y dos aminoglucósidos, Amicacina y Gentamicina. Las cepas aisladas correspondieron a: P. aeruginosa 116, P. cepacia 3, P. fluorecens 1 y P. putida 2. Se comprobó que 110 cepas de P. aeruginosa, 1 de P. cepacia y 1 de P. fluorescens, fueron sensibles a Piperacilina, estando estas sensibilidades por encima de las otras penicilinas estudiadas. Las cifras obtenidas con los aminoglucósidos ensayados, son similares para P. aeruginosa. Con respecto a CIM50 y CIM90 los resultados alcanzados con Piperacilina y relacionados con las dos penicilinas semisintéticas estudiadas, están muy alejados de los valores mínimos de sensibilidad, habiéndose observado, en relación a los aminoglucósidos, que si éstos no llegan al valor mínimo de sensibilidad, Piperacilina mantiene sus cifras por encima de los mismos, lo cual resulta importante desde el punto de vista terapéutico (AU)