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PubMed2025

Two CENH3 paralogs in the green alga Chlamydomonas reinhardtii have a redundantly essential function and associate with ZeppL-LINE1 elements.

Centromeres in eukaryotes are defined by the presence of histone H3 variant CENP-A/CENH3. Chlamydomonas encodes two predicted CENH3 paralogs, CENH3.1 and CENH3.2, that have not been previously characterized. We generated peptide antibodies to unique N-terminal epitopes for each of the two predicted Chlamydomonas CENH3 paralogs as well as an antibody against a shared CENH3 epitope. All three CENH3 antibodies recognized proteins of the expected size on immunoblots and had punctate nuclear immunofluorescence staining patterns. These results are consistent with both paralogs being expressed and localized to centromeres. CRISPR-Cas9-mediated insertional mutagenesis was used to generate predicted null mutations in either CENH3.1 or CENH3.2. Single mutants were viable but cenh3.1 cenh3.2 double mutants were not recovered, confirming that the function of CENH3 is essential. We sequenced and assembled two chromosome-scale Chlamydomonas genomes from strains CC-400 and UL-1690 (a derivative of CC-1690) with complete centromere sequences for 17/17 and 14/17 chromosomes respectively, enabling us to compare centromere evolution across four isolates with near complete assemblies. These data revealed significant changes across isolates between homologous centromeres including mobility and degeneration of ZeppL-LINE1 (ZeppL) transposons that comprise the major centromere repeat sequence in Chlamydomonas. We used cleavage under targets and tagmentation (CUT&Tag) to purify and map CENH3-bound genomic sequences and found enrichment of CENH3-binding almost exclusively at predicted centromere regions. An interesting exception was chromosome 2 in UL-1690, which had enrichment at its genetically mapped centromere repeat region as well as a second, distal location, centered around a single recently acquired ZeppL insertion. The CENH3-bound regions of the 17 Chlamydomonas centromeres ranged from 63.5 kb (average lower estimate) to 175 kb (average upper estimate). The relatively small size of its centromeres suggests that Chlamydomonas may be a useful organism for testing and deploying artificial chromosome technologies.

Chlamydomonas reinhardtii↗
PubMed1976

Experimental myocardial infarction. XIII. Sequential changes in left ventricular pressure-length relationships in the acute phase.

Diastolic pressure-length relationships of an ischemic region of the canine left ventricle were measured over a six-hour period following left anterior descending coronary artery ligation, and their evolution was compared with the extent of systolic aneurysmal bulging. Normalized ischemic segment length excursion, which after coronary artery ligation may be taken as a measure of systolic aneurysmal bulging, increased during the first hour after ligation but thereafter declined toward control values. Concurrently, reciprocal changes were demonstrated in the slope of the end-diastolic pressure-length curves obtained during transient pressure loading of the left ventricle. These data show that the magnitude of acute systolic aneurysmal bulging followed experimental coronary artery ligation is determined not only by loss of contractile function, but also by changes in passive pressure-length relationships of the myocardium. Moreover, the results indicate that development of akinesis in experimental ischemia, heretofore demonstrated only in the chronic phase of infarction, may begin within hours of the onset of myocardial ischemia.

Acute Disease↗
PubMed1982

Spontaneous changes in left ventricular function over the first 24 hours of acute myocardial infarction: implications for evaluating early therapeutic interventions.

The spontaneous changes in left ventricular ejection fraction (LVEF) during the first 24 hours of a first transmural infarction were assessed in 34 patients by serial gated cardiac blood pool imaging. Major therapeutic interventions with a view to limit infarct size were not used. Four determinations of LVEF were performed. Study 1 was performed as soon as possible after admission to the hospital. Studies 2 and 3 were performed 2 and 4 hours, respectively, after study 1. Twenty-four patients (70%) had study 1 within 6 hours after the onset of acute chest pain and 10 had it 6-12 hours after the onset of chest pain. Study 4 was performed 24 hours after the onset of chest pain. Compared with study 1, 19 of 34 patients (56%) had spontaneous changes in LVEF in at least one of the subsequent studies, exceeding the expected variability in stable patients. The changes ranged from a 32% increase to 14% absolute decrease. LVEF improved in 11 patients and deteriorated in eight. These spontaneous changes in left ventricular performance indicate that a single assessment of LVEF during the early hours of transmural myocardial infarction may not properly characterize cardiac performance in an individual patient and may not be the most appropriate reference against which to compare subsequent evolution of left ventricular function. These data may have implications for studies of the effects of early therapeutic interventions on LVEF.

Adult↗
PubMedDate not supplied

Aphasia outcome in stroke: a clinical neuroradiological correlation.

Fourteen aphasic patients with acute onset of thromboembolic cerebrovascular insults demonstrable by angiography or radioscintigrams who were available for long-term follow-up have been studied. Their aphasia evolution was compared with acute angiographical and radioisotopic findings, and the lesions shown by follow-up computerized axial tomography (CT). Angiographical site of occlusion, evidence of early reopening of occluded vessels, and radioisotopic flow asymmetries including the "hot-stroke" luxury perfusion failed to correlate with aphasia outcome. Radioisotopic static images were more helpful by depicting lesion location and number but lacked the definition seen on the CT scan. The long-term CT scan by showing the size, location and number of lesions had a good correlation with aphasia outcome. Those patients with large dominant hemisphere involvements, either one large or many smaller lesions, fared poorly while those with lesser lesions did better. Bilateral lesions, at times evasive clinically, helped to account for significant aphasia residuals.

Adult↗
PubMed2026

Uncovering the early and conserved molecular mechanisms of root nitrogen foraging in model and crops.

BACKGROUND: Nitrogen (N) foraging, the ability of plants to promote preferential root growth in N-rich patches of soil, is fundamental to the competitiveness and wellbeing of plants. A unique “split-root” system, where a heterogenous N environment stimulates root foraging, provides a powerful experimental model to study the mechanisms underlying root foraging in model (Arabidopsis) and/or crop plants. RESULTS: We used the split-root set up to capture early molecular events involved in systemic N-signaling after exposure to a heterogeneous N signal, through time-course transcriptomic analysis across shoots and roots of Arabidopsis. We found that a histone methyltransferase, SET DOMAIN GROUP 8 (SDG8), is necessary for root N-foraging, suggesting a previously unknown role for chromatin regulation in mediating the preferential root growth response to colonize N-rich patches. To determine if the underlying molecular mechanism is conserved in evolution, we compared the root foraging behavior from model-to-crop (Arabidopsis, tomato and maize). Our analysis showed the model and crop species shared a root N-foraging growth response, with some variation among specific genotypes. Interestingly, we observed both shared and distinct transcriptional responses to heterogenous N environments among these three species. CONCLUSIONS: Our study has generated insights into the molecular basis of root N-foraging, with the potential to improve nutrient use efficiency in crop plants in a heterogeneous field environment.

Crops, Agricultural↗
PubMed2026

Genomic Identification and Comparative Characterization of Chemosensory Genes in Two Walnut Pests.

Conogethes punctiferalis (generalist) and Atrijuglans aristata (specialist) are important pests of walnut fruits. Chemosensory genes play critical roles in host location and mating, making them promising candidates for pest management research. However, genome-wide identification of these gene families has not yet been performed for either species, and cross-species comparisons are often confounded by differences in annotation quality and methodology. Here, we employed a unified pipeline for genome annotation and gene family identification to systematically characterize the odorant receptor (OR), gustatory receptor (GR), odorant-binding protein (OBP), and chemosensory protein (CSP) genes of both species and further analyzed their physicochemical properties, chromosomal distribution, and phylogeny. Genome annotation identified 13,236 and 14,083 protein-coding genes in C. punctiferalis and A. aristata, respectively, with BUSCO completeness of 94.6% and 94.5%. We identified 121 candidate chemosensory genes in C. punctiferalis (46 ORs, 23 GRs, 32 OBPs, and 20 CSPs) and 137 in A. aristata (65 ORs, 26 GRs, 28 OBPs, and 18 CSPs). Notably, A. aristata possesses more OR genes (65) than C. punctiferalis (46). Both species possess a single conserved ORco, with three and four pheromone receptor (PR) genes in C. punctiferalis and A. aristata, respectively. Chemosensory genes were either dispersed or tandemly arrayed on chromosomes, with each family clustering into conserved functional branches. This study provides a reliable foundation for comparative chemosensory evolution studies and a catalog of candidate genes for future functional validation.

Atrijuglans aristata↗
PubMed1976

Cerebral distress in full-term newborns and its prognostic value. A follow-up study of 90 infants.

The history of 90 full-term infants with neonatal cerebral distress was examined. Informations concerning pregnancy, delivery, neonatal status, clinical and laboratory evolution were compared with final outcome in each case. It was then possible to distinguish certain clinical features significantly associated with poor prognosis. After statistical analysis, different adverse criteria were selected, such as severe neonatal asphyxia, associated respiratory disorders, acute anemia, and especially neurological signs with regard to their chronology. This part of the study has resulted in a classification of the neurological signs and has permitted the description of both malignant and benign cerebral distress syndromes.

Anemia, Neonatal↗
PubMedDate not supplied

[Coagulation factors during the development of common viral hepatitis].

The authors have analysed the development of various coagulation factors in 104 cases of common virus hepatitis in young adults. Total plasma coagulability, the prothrombin complex, factors VIII and IX, fibrination and fibrinolysis were followed up during this evolution and compared, using the usual statistical methods, with the results of the same investigations carried out on 100 healthy subjects belonging to the same age-group and on 31 patients suffering from cirrhosis of the liver. Statistical methods showed up the slightest disturbances of any significance which would have been overlooked if individual results only had been examined. As it was, there was total plasma hypercoagulability which was at its maximum at the onset of development but which persisted until the 7th week. It was mainly connected with an abnormality at the second stage of fibrination, that is : polymerisation of the fibrin monomers. The results obtained do not allow a conclusion to be drawn as to whether there exists an antipolymerase or dysfibrinogenaemia. Later research dealing specifically with the chemical structure of fibrinogen in hepatitis should provide further information. In practice, assessment of total plasma coagulability, using cephalinkaolin time, and analysis of fibrination by thrombin time are of definite value on account of their sensitivity.

Adult↗
PubMed1992

cDNA cloning and sequence comparisons of human and chicken muscle C-protein and 86kD protein.

Thick filaments in vertebrate striated muscles are composed of myosin heavy chain (MHC) and myosin light chains (MLCs) plus at least eight other proteins: C-protein, 86kD protein (birds) or H-protein (mammals), M-protein, myomesin, titin, MM-creatine kinase, skelemin, and AMP-deaminase. Except for CPK and AMP deaminase, none have well defined functions. Analysis of cDNA clones encoding chicken C-protein and 86kD protein has revealed a high degree of shared amino acid identity, particularly in the C-terminal 40kD. To identify functionally significant regions, the human counterpart of each protein was cloned, sequenced and analysed. Two human C-protein cDNAs were isolated with significant homology to chicken fast C-protein. Clone H75, with 69% identity to chicken fast C-protein, shows the same pattern of hybridization as the chicken fast C-protein in chicken muscles. The other clone, H8 with 60% identity, shows a pattern of hybridization in chicken muscles which is consistent with the expression of chicken slow C-protein. The human 86kD protein shares 66% DNA sequence identity with the chicken 86kD protein. Assuming that essential sequences would be conserved during evolution, we compared the chicken and human proteins using PALIGN. Chicken and human fast C-proteins possess 66% peptide identity over their deduced length plus 10% conservative substitutions. Human slow C-protein and chicken fast C-protein share 44% peptide sequence identity, plus 16% conservative substitutions. Chicken and human 86kD proteins are also very similar: 54% peptide identity plus 20% conservative substitutions. This high degree of sequence identity between chicken and human C- and 86kD proteins suggests selective pressure on the primary sequence. Recent primary sequence analyses of projectin and mini-titins from Drosophila, twitchin from C. elegans, C-protein, smMLCK, 86kD protein, and M-protein from the chicken, titin from the rabbit, and skelemin from the mouse reveals that all these proteins possess multiple internal repeats of approximately 100 amino acids. These repeating domains are of two types: one is homologous to the internal repeats which define the C-2 subset of the immunoglobulin superfamily, the other is related to the fibronectin type III repeat. Both human C-proteins possess comparable internal repeats and preliminary evidence suggests the presence of the same repeats in human 86kD. This duality of repeat structure is found in many extracellular proteins and is typified by the N-CAMs.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acid Sequence↗
PubMed1992

[Fluconazole treatment of cryptococcal meningitis associated with HIV infection. Presentation of 4 cases].

We present four cases of C. neoformans meningitis (CNM) in patients with Human Immunodeficiency Virus (HIV) infection treated with fluconazole p.o. at an initial dose of 400 mg followed by 200 mg/day during a follow up period ranging from 3 to 12 months, and who presented an excellent clinical evolution. When comparing them to our previous cases who were treated with Amphotericin-B in combination with 5-fluorocytosine, a decrease in mean hospital stay (p less than 0.001) and a smaller incidence of secondary effects were observed. Treatment with fluconazole seems to be an effective alternative in treatment of CNM. Future greater studies are needed to confirm this findings.

Administration, Oral↗
PubMedDate not supplied

[Late complication of diabetes mellitus of pancreatic origin].

At Instituto Nacional de la Nutrición SZ in Mexico City, we reviewed 30 years of experience and selected 46 patients with Pancreatic Diabetes (PD), without family history of Diabetes Mellitus (DM) with at less two years of follow-up. Alcoholic chronic pancreatitis (CP) was found in 36 patients, in seven it was idiophatic and in three was secondary to pancreatectomy. We compared the evolution of this patients with a group of (DM) patients similar in age, sex, glucemic control and time of onset. There were no statistical differences between groups in the follow-up of diabetic complications, only it was found a tendency to have higher lipid levels, macroangiopathy and retinopathy in those with DM. We concluded that CP have similar evolution as DM and could have deleterous complications in the large follow up.

Adult↗
PubMedDate not supplied

[Evaluation trial on the efficacy of neuroleptics on the outcome of schizophrenia].

Feasible and ideal methodological conditions lacking, we have tried an evaluation concerning the efficacy of neuroleptics upon the course of schizophrenia by comparing the evolution of homogeneous studies before and since the neuroleptic period. On the short term, neuroleptics are significantly more effective than the placebo upon schizophrenic symptoms and prevent the relapses in an noteworthy manner. On the long term, the evolution is significantly better for follow-up studies treated by neuroleptics (60% of patients improved) than for the non-treated follow-up studies i.e. before neuroleptic period (27.5% of patients improved). The time of the follow-up has an effect on the course of schizophrenia. Before neuroleptic periods, the schizophrenic process beyond 6 to 10 years was either stabilized or worsened. On the contrary, since the neuroleptic period, the number of improvements continued to increase after 12 years time (79.5% of patients improved for the follow-up beyond 12 years time versus 60% under 12 years). These improvements include paranoid and hebephrenic forms. On the contrary, catatonic forms had decreased very much since the utilization of neuroleptics (they moved from 18 to 28% before neuroleptic periods to 2% after the beginning of utilization of neuroleptics). If neuroleptics have undeniable action upon the schizophrenic symptomatology, they also act, on the long term, upon the social course of schizophrenia (30% of social remission before neuroleptic period versus 50% since neuroleptic period).

Antipsychotic Agents↗
PubMed1991

[Laparoscopic cholecystectomy as evolution of traditional cholecystec- tomy. Comparative evaluation].

Laparoscopic cholecystectomy (LC) is a minimally invasive method of removing the gallbladder that has become an accepted procedure all over the world. Authors performed 200 LC and compare the results of first 70 procedures with a matched group of patients who have undergone traditional cholecystectomy (TC) to evaluate its safety and efficacy. The average length of operation in the LC group was 64.5 +/- 26.3 min as compared to 68.5 +/- 22.5 min in the TC group. The difference between the incidence of postoperative complications in the 2 group was not statistically significant. The average length of stay in the LC group was 2.3 +/- 1.9 days versus 5.2 +/- 1.4 in the TC group. The difference is statistically significant. The comparison between the 2 methods shows less discomfort for LC patients during postoperative course. Pain was minimal, bowel evacuation was early and spontaneous, urinary retention only occurred in 2 patients versus 21 in TC group. The difference is statistically significant. Our results confirm laparoscopic cholecystectomy is a safe, effective and cost-efficient alternative to open cholecystectomy.

Adult↗
PubMed1990

[Inflammation proteins in Horton's disease. Prospective study of 25 patients].

In a study of 25 giant cell arteritis patients, whose diagnoses were made by temporal artery biopsy, the authors compared the evolution of the erythrocyte sedimentation rate (ESR) with those of the acute phase proteins (APP): fibrinogen (F), C reactive protein (CRP), orosomucoid (O), haptoglobin (H) and alpha 2-globulins (alpha 2-G), before, during and after corticotherapy; 165 laboratory analyses were made. Prior to treatment, ESR was increased in 96% of the patients, O and H in 100%, F and CRP in 96% and alpha 2-G in 92%. CRP showed the greatest mean increase (21x). Statistically significant positive correlations were found between ESR and alpha 2-G, F, CRP and O. No significant relationship was observed between APP and the occurrence of ophthalmological complications or the length of treatment. The CRP level returned to normal within the first week of steroid therapy for 76% of the patients, before ESR, F and O. During the withdrawal phase of corticotherapy, an ESR greater than 30 mm almost always corresponded to an inflammatory syndrome and an ESR of less than 15 mm to its absence (kappa coefficient = 0.64, p less than 0.001); however, an ESR between 15 and 30 mm did not enable us to draw a conclusion as to the absence or presence of such a syndrome. After terminating steroid therapy, the relationship between ESR and an inflammatory syndrome was weaker (kappa coefficient = 0.57, p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Staging of spinal metastasis using special techniques of magnetic resonance imaging].

The diagnosis of spine metastasis is a problem of great interest which leaves many questions unanswered. In this field MR imaging plays a fundamental role, as the only technique able to directly demonstrate the changes in bone marrow tissue, bound to tumoral activity. The introduction of gradient-echo (GE) sequences has helped reduce examination time. Moreover, with the accurate choice of pulse-sequence parameters (TR, TE, flip angle) additional information is acquired which is not yielded by conventional spin-echo (SE) sequences. Our study was aimed at evaluating MR sensitivity in the different stages of bone metastatic evolution. The comparative adequacy was evaluated of combined bone scintigraphy and conventional radiology versus MR imaging in 62 patients with vertebral metastases. Time interval between bone scan and/or radiological study and MR exam ranged from 10 days to 8 months. SE and GE T1-weighted images, and SE and GE T2-weighted images on the sagittal plane were employed, and axial images; coronal images were rarely acquired. Metastases were demonstrated by MR imaging at 122 vertebral levels, versus 88 true positives of combined scintigraphy and conventional radiology. Scintigraphic false-positives were observed at 15 vertebral levels, versus 9 with radiography. GE sequences were superior to SE ones in detecting vertebral morphologic lesions and bone marrow involvement thanks to their improved resolution and sensitivity. Moreover, GE sequences demonstrated tumoral bone marrow spread and persistent tumoral activity in the follow-up of spine metastases. Our results point to GE sequences as those of choice because of their higher resolution and sensitivity, which also allow response to treatment to be evaluated.

Humans↗
PubMedDate not supplied

[Model for the regional allocation of the National Health Care Fund].

In 1978 a National Health Service (Servizio Sanitario Nazionale = SSN) was constituted in Italy which exercises jurisdiction in the sector of health care and is duty bound to assist all citizens. Basically speaking, the NHS is organized on three levels (national, regional and local) with the management of direct operations assigned to the (about 700) Local Health Boards (Unità Sanitaria Locale = USL) each of which covers a well determined territorial area. The Authors indicate that rarely discussed or evaluated are the procedures for the regional allocation of health care funding which is determined by Parliament within the ambit of the National Budget (The National Health Care Fund). The current allocation model distributes the available capital resources for each expense item (e.g. hospitalization, pharmaceutical assistance, etc.) on a per capita basis with respect to the regional populations modified in order to allow for differing degrees of health care requirements. The regional populations are subdivided into broad age groups (e.g. children, intermediary, the elderly) with specific weighting factors expressing the different level of health care requirements. The application of these weighting factors alters the regional populations (with no change in the total population of the country) in order to express them in equivalent units with respect to the health care need. Moreover, standardized death rates are introduced into the model as indicators of the different health risk, and their application leads to a further modification in the level of the regional populations so as to express them in equivalent units with respect to the health risk as well. Once the available financial resources have been subdivided in this "theoretical" way, the following corrective factors are applied: a) hospital mobility correction factor: the regions with a credit admissions balance are assigned an additional cost which is borne by the regions with a debit admissions balance; b) historical expenditures correction factor: a comparison is made between the theoretical allocation and the allocation according to expenditures ascertained in 1985, and the final allocation falls into an intermediary position; s) Local Health Board income correction factor: the assignment of funds is reduced in direct proportion to the estimated income specific to the Local Health Boards of each region. The authors point out that even though this model represents a positive evolution when compared to the superficial criteria of past expenditure levels, it does manifest application potential limits.(ABSTRACT TRUNCATED AT 400 WORDS)

Financing, Government↗
PubMedDate not supplied

[Attitudes toward epilepsy in Majorca].

We created a questionnaire in order to evaluate the attitude toward epilepsy among the general population in Majorca Island, Spain. We made 1,164 interviews, divided fifty per cent between city and rural inhabitants. We studied the level of epilepsy knowledge in the population, and we compared the evolution of positive attitude of our study with others from Spain and the USA. We also studied the relationship between the variables considered and the two basic attitudes (integration-positive and stigmatization-negative). These two patterns were suggested to be associated with several trends of the population.

Attitude to Health↗
PubMed1987

Biochemical changes during sucrose deprivation in higher plant cells. Phosphorus-31 nuclear magnetic resonance studies.

An experimental arrangement was described that enables nuclear magnetic resonance spectra of compressed plant cells to be recorded while circulating a medium through the sample. The system provided a convenient arrangement for monitoring by 31P NMR the behavior of plant cells over a long period of time under different conditions such as sucrose starvation. Perfusion of compressed sycamore cells with sucrose-free culture medium triggered a progressive decrease in the glucose 6-P and uridine-5'-diphosphate-alpha-D-glucose resonances over 30 h. When almost all the intracellular carbohydrate pool had disappeared the nucleotide triphosphate resonances decline progressively. These changes were accompanied by a Pi accumulation in the vacuole and a phosphorylcholine (P-choline) accumulation in the cytoplasm. The very long lag phase observed for ATP and P-choline evolution was comparable with that observed for the progressive intracellular digestion of cytoplasmic constituents (Journet, E., Bligny, R. and Douce, R. (1986) J. Biol. Chem. 261, 3193-3199). Addition of sucrose in the circulating system after a long period of sucrose starvation led to a disappearance of the cytoplasmic Pi resonance and a marked increase in that of glucose 6-P. Under these conditions the vacuolar Pi pool did not fluctuate to buffer the Pi in the cytoplasm. The results suggest that Pi which has been sequestered in the vacuole during the course of sucrose starvation is not restored to the cytoplasm for rapid metabolic processes. Furthermore, the presence of P-choline in plant cells in large excess should be considered as a good marker of membrane utilization after a long period of sucrose starvation and is very likely related to stress.

Adenosine Triphosphate↗