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Biomedical subjects

D Long

Publications and source records attributed to D Long.

At least 19 recordsLinked to original sources
PubMed2000

ACAULIS5, an Arabidopsis gene required for stem elongation, encodes a spermine synthase.

Polyamines have been implicated in a wide range of biological processes, including growth and development in bacteria and animals, but their function in higher plants is unclear. Here we show that the Arabidopsis: ACAULIS5 (ACL5) gene, whose inactivation causes a defect in the elongation of stem internodes by reducing cell expansion, encodes a protein that shares sequence similarity with the polyamine biosynthetic enzymes spermidine synthase and spermine synthase. Expression of the recombinant ACL5 protein in Escherichia coli showed that ACL5 possesses spermine synthase activity. Restoration of the acl5 mutant phenotype by somatic reversion of a transposon-induced allele suggests a non-cell-autonomous function for the ACL5 gene product. We also found that expression of the ACL5 cDNA under the control of a heat shock gene promoter in acl5 mutant plants restores the phenotype in a heat shock-dependent manner. The results of the experiments showed that polyamines play an essential role in promotion of internode elongation through cell expansion in Arabidopsis: We discuss the relationships to plant growth regulators such as auxin and gibberellins that have related functions.

Alleles↗
PubMed2000

Changes in a murine leukemia virus (MLV) receptor encoded by an alphavirus vector during passage in cells expressing the MLV envelope.

We constructed alphavirus vectors encoding the ecotropic murine leukemia virus (MLV) receptor mCAT1. Cells electroporated with these vector RNAs expressed mCAT1 protein and fused with cells that expressed a fusogenic form of the MLV envelope on the cell surface. Electroporated cells also released submicron particles that were infectious in envelope-expressing cells. Infection resulted in giant syncytia that could be enumerated by plaque assay. Cell-free supernatants could be serially passaged and contained up to 10(4) infectious units/ml. To determine whether repeated passage would select for functional variants of the receptor, we analyzed mCAT1 amplified by RT-PCR after 12 serial passages. Several amino acid substitutions were identified that encoded functional receptor variants. In independent experiments, variants containing an isoleucine or a leucine instead of a phenylalanine at position 224 in the third extracellular domain of the receptor arose spontaneously and outgrew the parental vector, indicating that mutations at this site are highly selected in this system. This region of the receptor has previously been implicated in the envelope-receptor interaction. This alphavirus vector system provides a novel method for generating and selecting functional variants of viral receptors

Alphavirus↗
PubMed2000

Announcements

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Journal Article↗
PubMed2000

Announcements

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Journal Article↗
PubMed2000

[Determination of scalp ER and AR of patients with male pattern baldness and the effects of hair transplantation on them].

OBJECTIVE: To study the role of sex hormone receptor capacity of the scalp in male pattern baldness(MPB). METHODS: Estrogen receptor(ER) and androgen receptor(AR) assays were performed using fluorescent steroid hormone conjugate technique (FSHCT) in hairness and bald scalp in 8 patients with MPB. Changes of ER and AR capacity in recipient and donor sites of hair transplantation in MPB scalps were examined. RESULTS: The percentage of AR staining cells in the outer root sheath, sebaceous gland and bulb papilla of the lesional scalps was significantly higher than that of hairness scalps (P < 0.01). The percentage of ER positive cells in the outer root sheath of lesional scalps increased significantly (P < 0.01). CONCLUSION: Changes of contents of sex hormone receptors(SHR) in some sensitive area of the scalp induce MPB.

Adult↗
PubMed1999

Electroosmotic Flows Created by Surface Defects in Capillary Electrophoresis.

We compute the electroosmotic flow in nonuniformly charged planar and cylindrical capillaries for the limit of low-Reynolds-number flows and thin Debye layers. Analytical formulae for the velocity field are provided for the general case of an arbitrary surface inhomogeneity but we also focus on various specific defect geometries. Many important features can be obtained from the simple lubrication approximation. The pressure jump induced by the presence of such surface defects is calculated and the possible occurrence of recirculating flows is discussed, as are effects of the flow perturbations on dispersion in capillary electrophoresis. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Sweet's syndrome and erythema nodosum: the simultaneous occurrence of 2 reactive dermatoses.

BACKGROUND: The simultaneous occurrence of Sweet's syndrome (SS) and erythema nodosum (EN) in 1 patient is rare. Our review of the literature revealed only 11 biopsy-proved cases in which the 2 reactive dermatoses occurred together. None were associated with an underlying malignant neoplasm. OBSERVATIONS: We report a biopsy-proved case of SS and EN occurring simultaneously in a patient with an underlying malignant neoplasm (specifically, acute myelogenous leukemia). We also report another biopsy-proved case of SS and EN occurring simultaneously in a patient with underlying Crohn's disease. CONCLUSIONS: The simultaneous occurrence of SS and EN in 1 patient is rarely reported. Both disorders are reactive dermatoses that share many overlapping features. Although individually distinctive, SS and EN are also part of a growing continuum of reactive dermatoses. Our expanded understanding of the similarities and simultaneous manifestation of SS and EN may help us in the future to identify a common underlying mechanism of pathogenesis.

Adult↗
PubMed1999

[The value of anesthesia consultation in relation to the single preanesthetic visit].

OBJECTIVE: In France, a preanaesthetic assessment (PAA) several days prior to hospital admission for a scheduled surgical or diagnostic procedure under anaesthesia, associated with a preanaesthetic visit (PAV) the day before, are compulsory. This study aimed at comparing the benefits of PAA with those of a PAV not preceded by a PAA. STUDY DESIGN: Prospective, controlled, randomized study. PATIENTS: The study included 296 patients undergoing either a urologic, or ophthalmologic, or ENT procedure, randomly allocated either to a PAA (followed by a PAV) group or a PAV (without previous PAA) group. METHODS: The main criterion of comparison was the duration of preanaesthetic hospital stay and the secondary criteria were the incidence of procedure postponements and patients' satisfaction respectively. RESULTS: In the PAA group, the preanaesthetic hospital stay was shorter by 0.4 days (P = 0.001). Out of the 19 postponed procedures (7%), the cause of postponement was a medical one in 15 patients: 13 in the PAV group and 2 in the PAA group respectively (P = 0.009). The PAA was not considered as a constraint by most patients. CONCLUSION: The PAA shortens the duration of preanaesthetic hospital stay and decreases the incidence of procedures postponed for a medical cause.

Analysis of Variance↗
PubMed1999

The heat moisture exchange device (HME) in neonatal ventilation.

The objective of this study was to compare the safety and efficacy of the Heat Moisture Exchange (HME) device with conventional humidification in neonates. Sixty-four neonates were randomized at intubation to receive conventional humidification (CH) (n = 34) or HME, via a Neoaid device (n = 30). Groups were compared for intrinsic characteristics and outcome variables. Data were assumed nonparametric and analyzed by Mann-Whitney and Fisher's Exact test. No significant differences were found in group characteristics or outcome variables. Trends were noted for documented patent ductus arteriosus (PDA), endotracheal tube blockage, and positive endotracheal aspirate culture. Rate of pneumothorax 2/34 (CH) versus 4/30 (HME) (p = 0.4); rate of tube blockage 3/34 (CH) versus 2/30 (HME) (p = 1.0); rate of PDA 8/34 (CH) versus 14/30 (HME) (p = 0.093) and rate of endotracheal colonisation 1 7/34 (CH) versus 9/30 (HME) (p = 0.17). No significant difference was found for duration of ventilation or period in greater than 40% oxygen between the two groups. There were no significant outcome differences between CH and HME. The HME device was cost-effective and simple to use. A larger multicenter trial is warranted to confirm the efficacy of HME.

Equipment Design↗
PubMed1999

[Prevention and treatment of eyelid retraction and ectropion following lower eyelid blepharoplasty with tarsal tuck procedure].

OBJECTIVE: To prevent or decrease eyelid retraction and ectropion following lower eyelid blepharoplasty. METHODS: The tarsal tuck procedure was performed during lower eyelid blepharoplasty to tighten the lower eyelid. This method had been used since 1991. RESULTS: After the operation, the lower eyelid was tensional and steady. The complications of eyelid retraction and ectropion were diminished. CONCLUSION: The pathologic basis of the eyelid bag is that the supporting tissues become lax so that the lower eyelid and lateral canthus move downwards. The exact aim of the tarsal tuck procedure is to correct these pathologic changes.

Blepharoplasty↗
PubMed1998

[Graft function following renal transplantation in children].

BACKGROUND: Since renal transplantation is known to be the best choice for the growing child with end-stage renal failure, we prospectively evaluated early and late graft function in transplanted children. POPULATION AND METHODS: The study included 78 children (32 girls, 46 boys) 10.4 +/- 0.6 years at the time of transplantation. Renal investigations were performed at 3, 6 and 12 months post-transplantation and yearly thereafter. Inulin clearance was used to evaluate the glomerular filtration rate (GFR), and the reabsorption rates of Na, P and Ca were measured concomitantly. RESULTS: The overall adjusted GFR was approximately 70 mL/min/1.73 m2 and remained unchanged during the first 5 years post-transplantation. In the mean time the absolute GFR increased significantly, suggesting a remaining capacity for compensatory hypertrophy of the transplanted kidney. Renal function was significantly influenced by the number of rejection episodes during the first 2 years post-transplantation but no correlation was found between GFR and the number of HLA mismatches or the use of preemptive transplantation.

Child↗
PubMed1998

Abuse against women in rural Minnesota.

The purpose of this study was to examine the prevalence of physical, emotional, and sexual abuse in women seeking care in rural medical clinics and WIC supplemental food program sites, as well as to examine demographic and health characteristics related to abuse. This was a descriptive, cross-sectional study using a self-administered, anonymous survey. Data were collected in 8 medical clinics and 17 WIC supplemental food program sites in 9 counties of west-central Minnesota during January and February, 1997. The survey instrument asked brief screening questions on physical, emotional, and sexual abuse as well as demographic and health related questions designed to reflect the rural population and characteristics. The survey results showed that in the prior 12 months, 109 (6.6%) of the respondents reported physical abuse, 347 (21.1%) reported emotional/verbal abuse, and 35 (2.1%) reported sexual abuse. Proportional increases in risk of current abuse relative to married women were 2.1 for single, 2.5 for divorced, and 6.5 for separated women, after adjusting for other important variables. Single women with a recent status change had significantly higher risk of current abuse than women with a recent status change at all other marital status levels in adjusted analyses. Women who reported some form of abuse before age 18, and women reporting abuse as an adult prior to the last 12 months, were significantly more likely to report current abuse in all analyses. Prior abuse as an adult was the single best predictor of current abuse in a final logistic regression model.

Adult↗
PubMed1998

[Prevention and treatment of postoperative complications following skin soft tissue expansion].

Since 1987, One hundred and fifty-four patients suffered from alopecia, neck and facial scar, and nasal defect had been treated with skin soft tissue expansion. The incidence of complication was decreased markedly, compared to previons report which was 11.7%. Two cases of this group were given up this procedure. The lessous learned from these case were as following. Strictly evaluated the case according to the indication, examined the expander carefully, improved the techniques to inbed the expander and infilled the sailine, those of which could obtain satisfactory result.

Adolescent↗
PubMed1998

Acute hemorrhagic edema of infancy: Finkelstein's disease.

Acute hemorrhagic edema of infancy (AHEI) is a benign form of leukocytoclastic vasculitis limited to the skin, which occurs in children younger than 2 years of age. The abrupt onset of fever, peripheral edema, and purpuric targetoid plaques in an infant may be confused with other dermatoses such as Henoch-Schönlein purpura, Sweet's syndrome, erythema multiforme, or septic vasculitis. Laboratory studies of patients with AHEI typically show normal results and the disorder follows a benign course with spontaneous resolution occurring in 1 to 3 weeks. We present a case of AHEI occurring in a 7-month-old boy and review the characteristic features of this acute dermatosis.

Acute Disease↗