Leukocytoclastic vasculitis and polyarthritis associated with Mycoplasma pneumoniae infection.
Explore the source record for details and available documents.
Adult↗
Biomedical subjects
R Hernandez
Publications and source records attributed to R Hernandez.
Bacterial artificial chromosome (BAC) library as a tool for physical mapping of the archaeon Methanosarcina thermophila TM-1.
We have used a variety of methods to characterize the genome of the archaeon Methanosarcina thermophila TM-1. Pulsed-field gel analysis indicates a genome size of 2.8 Mb. We have constructed a bacterial artificial chromosome (BAC) library of M. thermophila and have used it to generate physical maps for this organism. The library is made up of 384 clones with an average insert size of 58 kb representing 8.0 genome equivalents. The utility of the library for low-resolution physical mapping was shown by identifying NotI linking clones and using these to order the NotI macrorestriction fragments of M. thermophila into a 2.8 Mb map. Hybridization of nine single copy genes and a 16S rRNA sequence to these macrorestriction fragments forms the basis for the first genetic map in this organism. High-resolution physical maps, consisting of overlapping clones, have been created using HindIII fingerprints of BAC clones. In this way, we identified a minimal path of five clones that span a 270 kb NotI fragment. The ease of manipulating BAC clones makes the BAC system an excellent choice for the construction of low-resolution and high-resolution physical and genetic maps of archaeal genomes. It also provides a substrate for future genome-sequencing efforts.
Chromosome Mapping↗
Preferential induction of chromosome 1 multibranched figures and whole-arm deletions in a human pro-B cell line treated with 5-azacytidine or 5-azadeoxycytidine.
5-Azacytidine (azaCR) causes genomic demethylation and decondensation of juxtacentromeric heterochromatin in chromosomes 1, 9, and 16. We determined the karyotypes of a pro-B cell line (FLEB14) treated with azaCR or its deoxynucleoside analog (azaCdR). About 80% of the induced rearrangements were in chromosome 1, and almost 90% of these involved its pericentromeric region. Multibranched figures with up to seven chromosome 1 arms, as well as whole-arm deletions of this chromosome, were the predominant anomalies, often with one normal homolog of chromosome 1 present. Isochromosomes 1 and fusions in the pericentromeric regions of chromosomes 1 and 16 or chromosomes 1 and 9 were also seen. The overlap of the spectrum of chromosomal rearrangements in azaCR- or azaCdR-treated FLEB14 cells and in mitogen-stimulated lymphocytes from patients with a rare genetic disease (ICF) associated with localized DNA hypomethylation supports the hypothesis that the DNA demethylating activity of azaCR is essential for the induction of these pericentromeric rearrangements. These studies may help elucidate the overrepresentation of chromosome 1 pericentromeric rearrangements in many types of cancer cells.
Antimetabolites, Antineoplastic↗
High-fat sunflower and olive oil diets affect serum lipid levels in steatotic rat liver differently.
This work describes the long-term effects of two different diets, one rich in olive oil and the other in sunflower oil, on serum lipid and lipoprotein levels after the establishment of fatty liver in rats 8 and 15 months old. The serum lipid and lipoprotein levels as well as the steatotic process have been evaluated by biochemical and histological methods, respectively. The results showed that fatty liver was well developed with both long-term high-fat diets, and hepatocytes were filled with many lipid droplets. This process was more evident in the portal zones, where fat hepatocytes were more numerous. Serum total cholesterol (TC) and HDL-C levels were highest in the sunflower oil fed rats, whereas the TG and LDL-C levels were highest in the olive oil group. Finally, the atherogenic indexes (HDL/TC, HDL/LDL, HDL/(TC-HDL)) were higher in the sunflower oil diet group than in the olive oil group.
Animals↗
Low intensity physical training in older subjects.
BACKGROUND: This study was designed to evaluate the effects of a low intensity general training program (< 50% of heart rate reserve) on physical fitness of healthy older subjects, by comparing maximal and submaximal indices of training response. METHODS: Twenty-two volunteers over 60 years of age participated in the present study. The sample was randomly divided in an experimental group of 13 older subjects (3 men and 10 women, mean age 63.5 +/- 3 years) while the remaining 9 subjects (3 men and 6 women, mean age 64.2 +/- 4 years) served as inactive control group. After medical screening all participants were evaluated before and after 12 weeks in which the experimental subjects underwent a low intensity training. Each subjects-either inactive or active-performed two treadmill tests at two-days interval, to measure maximal and submaximal responses to exercise, respectively. Heart rate (HR), oxygen uptake (VO2) and pulmonary ventilation (VE) were measured using a telemetric apparatus. RESULTS: The major finding of the study was the significant improvement in submaximal response to exercise of experimental subjects, expressed by the reduction in HR, VO2 VE while VO2 max did not change. CONCLUSIONS: Thus, it appears that a low intensity general training similar to that followed in the present study may represent a good means to improve physical fitness in healthy elderly people. Similarly, this study supports the effectiveness of evaluation tests based on submaximal responses to exercise in this population.
Aging↗
Mutations in the endo domain of Sindbis virus glycoprotein E2 block phosphorylation, reorientation of the endo domain, and nucleocapsid binding.
Exposure of the carboxyl terminus (endo domain) of Sindbis virus membrane glycoprotein E2 to the cell cytoplasm is critical for the interaction of the nucleocapsid with viral envelope proteins in modified cell membranes. We have shown that the endo domain of PE2/E2 is initially translocated into membranes of the endoplasmic reticulum and subsequently drawn back into the cell cytoplasm during virus assembly. We suggested that phosphorylation of PE2/E2 might be responsible for the reorganization of the PE2/E2 carboxyl terminus. To test this hypothesis, two potential phosphorylation sites in the endo domain of E2, Thr398 and Tyr400, were changed by site-directed mutagenesis. Virus structural proteins are produced at normal levels in BHK-21 cells transfected with RNA containing the double mutation, nucleocapsids are formed, and the envelope proteins are exported from the endoplasmic reticulum; however, no virus is produced. The double mutation prevents phosphorylation of PE2/E2, and electron microscopy of cells transfected with the double mutant RNA reveals no attachment of nucleocapsids to cell membranes. The double mutation blocks exposure of the carboxyl terminus of E2 to the cytoplasm. Revertants of the double mutant to virus production all restored tyrosine at position 400 and restored the ability of the E2 protein to be phosphorylated. Although the threonine at position 398 is conserved among the alphaviruses, no revertant restored threonine at this position.
Amino Acid Sequence↗
The NEUROD gene maps to human chromosome 2q32 and mouse chromosome 2.
The Neurod gene is a basic-helix-loop-helix gene that regulates neurogenesis and is identical to the hamster beta2 gene that was cloned as a regulator of insulin transcription. Here we report the cloning of human NEUROD and mapping of the gene to human chromosome 2q32 and to mouse chromosome 2.
Amino Acid Sequence↗
Has laparoscopic cholecystectomy changed patterns of practice and patient outcome in Ontario?
OBJECTIVE: To examine the effect of the introduction of laparoscopic cholecystectomy (LC) on patterns of practice (number of cholecystectomy procedures, case-mix and length of hospital stay) and patient outcomes in Ontario. DESIGN: Cross-sectional population-based time trends using hospital discharge data. SETTING: All acute care hospitals in Ontario where cholecystectomy was provided. PATIENTS: All 119,821 Ontario residents who underwent cholecystectomy between 1989-90 and 1993-94. After exclusions (initial bile duct exploration, cancer, incidental cholecystectomy, or missing codes for age, sex or residence) 108,442 patients remained. OUTCOME MEASURES: Number of cholecystectomy procedures, proportion of patients with acute or chronic gallstone disease, length of hospital stay, and rates of death, readmission, and bile duct injury and other in-hospital complications after cholecystectomy by year. RESULTS: The number of cholecystectomy procedures increased by 30.4% between 1989-90 and 1993-94. The number of patients with chronic gallstone disease increased by 33.6%, and the number who underwent elective surgery increased by 48.3%. The proportion of procedures performed as LC increased from 1.0% in 1990-91 to 85.6% in 1993-94. Patients who received LC tended to be younger female patients with chronic gallstone disease with no coexisting conditions undergoing elective operations. The mean length of stay, adjusted for case-mix differences, was significantly lower in 1993-94 than in 1989-90 (2.6 days v. 7.5 days) (p < 0.05); the values for LC and open cholecystectomy in 1993-94 were 1.8 days and 7.3 days respectively. The decrease in the crude death rate over the study period (0.3% to 0.2%) was not significant (relative odds 1.10, 95% confidence interval [CI] 0.72 to 1.69). In 1993-94 the adjusted risk of readmission to hospital within 30 days was 1.38 (95% CI 1.19 to 1.58) as compared with 1989-90. Over the 5 years the rate of bile duct injuries tripled (0.3% in 1989-90 v. 0.9% in 1993-94). The adjusted risk of having at least one complication after cholecystectomy in 1993-94 was 1.90 (95% CI 1.75 to 2.07) as compared with 1989-90. CONCLUSIONS: LC has had a substantial effect on the number of cholecystectomy procedures performed, the type of patient having the gallbladder removed and the length of hospital stay. Death rates are unchanged, but the odds of readmission and in-hospital complications are both increased. Future research should be directed toward determining the reasons for the overall increase in rates, developing methods to reduce bile duct injuries and identifying other relevant outcomes, such as patient satisfaction with the procedure.
Adolescent↗
Percutaneous mitral valvuloplasty with the Inoue technique in a patient with heavily calcified interatrial septum.
A 75-year-old woman with severe rheumatic mitral stenosis was admitted for percutaneous mitral valvuloplasty. Two-dimensional echocardiography disclosed severe calcification of the posterolateral left atrial wall and interatrial septum. Percutaneous mitral valvuloplasty, using the inoue technique, was successfully performed after a transseptal puncture through the calcified interatrial septum, avoiding the need for surgical intervention.
Aged↗
Percutaneous mitral valvuloplasty for rheumatic mitral stenosis associated with cor triatriatum.
A patient with rheumatic mitral stenosis associated with cor triatriatum is described. The anomalies were detected by two-dimensional echocardiography and confirmed by transesophageal echocardiography. Percutaneous mitral valvuloplasty was successfully performed with the inoue technique. The clinical and technical implications during the procedure of this previously unreported association are discussed.
Adult↗
Polymerase chain reaction for the detection of Mycobacterium tuberculosis DNA in tissue and assessment of its utility in the diagnosis of hepatic granulomas.
A polymerase chain reaction (PCR) assay for the rapid identification of Mycobacterium tuberculosis, based on amplification of the IS6110 insertion sequences, was tested in paraffin-embedded tissue from 64 biopsy samples with either positive or negative cultures for Mycobacterium tuberculosis. The utility of this PCR assay in the diagnosis of tuberculosis among patients with hepatic granulomas (HGs) was then tested by examining 43 liver biopsy samples. They were classified as either having definitive or probable tuberculosis or as being of nontuberculous origin, on the basis of clinical and microbiologic data and on their response to antituberculous treatment. PCR was 100% sensitive in the diagnosis of culture-positive M. tuberculosis infection in the lymph node, lung, and liver. The sensitivity of the PCR in the diagnosis of HG of definitive tuberculous origin was 58%, and the specificity was 96%. PCR is a valuable test for the demonstration of mycobacterial DNA in tissues. Although it is not highly sensitive, the DNA amplification method may also be more sensitive than culture in the diagnosis of M. tuberculosis-associated HG.
Base Sequence↗
Narrative development in late talkers: early school age.
Children with slow expressive language development (SELD) as toddlers and a control group of children with normal language development (NL) were followed to early school age. Children with SELD were, at that point, subdivided into two groups: those who had moved within the normal range of expressive language (the History of Expressive Language Delay [HELD] subgroup); and those who continued to score below the normal range in expressive language at school age (the Expressive Language Delay [ELD] subgroup). During their kindergarten, first, and second grade years, they were administered a narrative generation task. Narratives were analyzed for MLU, lexical diversity, amount of information included, proportion of complete cohesive ties, and overall stage of narrative maturity. In kindergarten, children with normal language history scored significantly higher than those with HELD and ELD on lexical diversity and narrative stage; and higher than those with ELD in proportion of complete cohesive ties. In first grade, children with normal language history again scored significantly higher than those with HELD and ELD on narrative maturity, with no other significant differences. In second grade, there were no significant differences among the groups.
Age Factors↗
Spread of murine cytomegalovirus to inner ocular structures following disruption of the blood-retina barrier in immunosuppressed BALB/c mice.
PURPOSE: The aims of this study were to determine whether disruption of the blood-retina barrier (BRB) increases spread of murine cytomegalovirus (MCMV) to the eye after intraperitoneal inoculation and whether systemic immunosuppression influences the location of MCMV in the ocular compartment. METHODS: The BRB of the left eye of normal and immunosuppressed mice was disrupted by supraciliary inoculation of tissue culture medium followed 2 hours later by intraperitoneal injection of MCMV. Plaque assay of homogenized ocular tissue was used to determine the frequency of virus-positive eyes and the titer of virus in the eyes. Beta-galactosidase staining of frozen sections was used to locate virus in the eyes. RESULTS: In nonimmunosuppressed mice, the frequency of virus isolation, as well as the titer of virus, were significantly higher in eyes in which the BRB had been disrupted. Although the frequency of virus isolation was the same in both eyes of immunosuppressed mice, the titer of virus was significantly higher in the eye in which the BRB had been disrupted. The most striking result was that the location of virus was different in the nondisrupted eyes of immunosuppressed mice than it was in the disrupted eyes of immunosuppressed mice. In the former, virus was seen only in the outer ocular structures (conjunctiva, sclera, lacrimal gland), whereas in the latter, virus was observed in the retina and anterior segment (iris, ciliary body) as well as the outer ocular structures. CONCLUSIONS: The results of these studies suggest that ocular damage followed by increased spread of virus to and within the eye during systemic infection with CMV may be one mechanism by which development of CMV retinitis is facilitated in patients with acquired immune deficiency syndrome.
Animals↗
Autoregulation of renal and splanchnic blood flow following infra-renal aortic clamping is mediated by nitric oxide and vasodilator prostanoids.
OBJECTIVE: This study examines the hypothesis that nitric oxide and vasodilator prostanoids contribute to the autoregulation of renal artery and superior mesenteric artery (SMA) blood flow following infra-renal aortic clamping. EXPERIMENTAL DESIGN: Renal and SMA artery blood flow were measured in anesthetized rats. The rats received bolus injection of saline carrier, L-NAME (25 mg/kg) or indomethacin (15 mg/kg) prior to sham or infra-renal aortic occlusion. In vivo blood flow was measured 1, 30 and 60 minutes during aortic occlusion and 1, 30, and 60 minutes following release of the aortic cross clamp. RESULTS: Aortic occlusion transiently increased SMA blood flow but did not alter renal artery blood flow. Aortic clamp release resulted in a 40% decrease in both SMA and renal artery blood flow. L-NAME or indomethacin pretreatment decreased both SMA and renal artery blood flow at 60 minutes following infrarenal aortic occlusion. Indomethacin decreased SMA blood flow at 1 minute following unclamping of the aorta and L-NAME decreased SMA blood flow at 30 and 60 minutes following aortic clamp release. Both L-NAME and indomethacin markedly decreased renal artery blood flow at all time periods following aortic clamp release. CONCLUSIONS: These data suggest that renal and splanchnic vascular beds utilize endogenous vasodilator eicosanoids and nitric oxide to maintain blood flow during cross clamping and unclamping of the infra-renal aorta.
Animals↗
A cohort study on childhood asthma admissions and readmissions.
BACKGROUND: Admissions to hospitals for childhood asthma seem to be increasing, even though admissions for other childhood conditions are decreasing. We studied admissions and readmissions for childhood asthma in Ontario in an attempt to uncover factors relating to the admission patterns. METHODS: Using the hospital discharge data from the Canadian Institute for Health Information, 28,646 children with diagnoses of asthma were identified from April 1, 1989, to March 31, 1992. RESULTS: The admission rates for asthma among children in Ontario showed a 14.8% decrease from 1987 to 1992. This decline was observed primarily in 5- to 17-year-olds. Younger children had a fourfold risk of hospital admission for asthma. In the 4 years studied, 10,427 children (36.4%) were readmitted at least once, representing 22,114 readmissions, 16,196 (73.2%) of which were for asthma. The 6-month probabilities of readmission for asthma were 20.0% (0- to 4-year-olds) and 11.7% (5- to 17-year-olds). The estimated relative risks (RRs) indicated that younger children had a significantly higher risk of readmission for asthma (RR, 1.38; 95% confidence interval, 1.30 to 1.46) or asthma-related causes (RR, 5.02; 95% confidence interval, 4.16 to 6.05). CONCLUSIONS: The observed increasing trend in admissions for asthma among children in the 1970s and 1980s leveled off in the early 1990s. The declining admission rates were largely caused by the lower admission rates among school-aged children from 5 to 17 years. The relatively high admission and readmission rates of preschool children are still a concern. Further research is necessary to examine factors that influence admissions for asthma among young children.
Adolescent↗
[Therapy of extension deficits of the knee joint by arthroscopic arthrolysis and dorsal capsulotomy].
Loss of full knee extension is a typical complication of knee ligament surgery and is difficult to treat. We present a technique that is indicated especially in longstanding extension deficits and that combines arthroscopic arthrolysis and posterior capsulotomy. The intra-articular pathology is first treated by arthroscopic debridement and arthrolysis. Then a posteromedial arthrotomy is performed with the knee flexed 90 degrees. the posterior adhesions are divided under direct vision and finally the posterior capsule is detached completely from the distal femur. Twenty-one of 24 patients treated with arthroscopic arthrolysis and posterior capsulotomy from 1989 to 1993 were reviewed with a mean follow-up of 18 months (6-38). The mean extension deficit preoperatively was 17 degrees (10-30 degrees); symptoms persisted from 6 months to 7 years. The gain in extension by this procedure averaged 15 degrees; no patient had more than 5 degrees of extension deficit at follow-up. The knee function improved significantly (Lysholm score preoperatively 62, postoperatively 88, Tegner scale preoperatively 2.2, postoperatively 4.0). We conclude that posterior capsulotomy is a safe and efficient additional procedure to arthroscopic arthrolysis and is indicated in cases with chronic extension deficit after ligament surgery.
Adult↗
Pitfalls in nonrandomized outcomes studies. The case of incidental appendectomy with open cholecystectomy.
OBJECTIVES: To assess the short-term outcomes of incidental appendectomy through analysis of hospital administrative data and determine the consistency and plausibility of the observed results. DESIGN: Population-based historical cohort study. SETTING: All general hospitals in Ontario between 1981 and 1990. PATIENTS: Patients undergoing open primary cholecystectomy with (7846 exposed) and without (191,599 unexposed) incidental appendectomy. MAIN OUTCOME MEASURES: In-hospital fatality rates, complication rates, and lengths of hospital stay. RESULTS: Crude comparisons showed a striking and paradoxical reduction in mortality after cholecystectomy when incidental appendectomy was performed (odds ratio [OR], 0.37; 95% confidence interval [CI], 0.23 to 0.57; P < .001); mean length of stay was also lower by -0.46 day (P < .001). After adjustment for confounding differences, such as comorbidity and nonelective surgery, mortality and lengths of stay were similar for exposed and unexposed patients; but exposed patients showed a significant increase in nonfatal complications (OR, 1.53; 95% CI, 1.39 to 1.68; P < .001). Adverse effects from incidental appendectomy emerged consistently for all three outcomes only after restricting the analysis to subgroups of patients at low surgical risk. The increased mortality for exposed patients was largest among low-risk groups; for example, among those younger than 70 years undergoing elective surgery, the OR was 2.65 (95% CI, 1.25 to 5.64; P < .001). CONCLUSION: These findings suggest that incidental appendectomy is associated with a small but definite increase in adverse postoperative outcomes. However, plausible and consistent findings were only obtained after restricting the analysis to low-risk subgroups in which unmeasured differences in patients' baseline characteristics were less likely to confound adjusted outcome comparisons. This exercise highlights the potential pitfalls in nonrandomized outcomes comparisons using data sources with limited clinical detail, such as hospital discharge abstracts.
Adult↗
Diagnosis of aortic intramural hematoma by intravascular ultrasound imaging.
Our findings indicate the value of IVUS in the study of aortic intramural hematomas in ruling out other aortic diseases such as classic aortic dissection. This technique appears especially attractive for patients with suspected aortic dissection and a normal aortography.
Adolescent↗