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S McCormick

Publications and source records attributed to S McCormick.

At least 91 records · Page 5Linked to original sources
PubMed1989

Heat shock protein hsp70 cognate gene expression in vegetative and reproductive organs of Lycopersicon esculentum.

We have detected hsc70 gene expression (heat shock protein hsp70 cognate) during vegetative growth and reproductive development in tomato (Lycopersicon esculentum). Using RNA from a tomato hsc70 cDNA as a probe in in situ hybridizations, we have determined expression patterns of hsc70 in nonstressed tomato roots, stems, leaves, flowers, and developing fruits. We have localized high levels of hsc70 transcript to the vascular system of the ovary, dividing cells of the lateral root tips, and the inner integument of developing seeds. We also see expression in the transmitting tissue, in immature anthers, and in embryos. We cannot detect expression in mature pollen, xylem, or ovules. These data indicate that the expression of at least some tomato hsp70 family members is developmentally regulated.

Journal Article↗
PubMed1989

Transient expression of chimeric genes delivered into pollen by microprojectile bombardment.

Chimeric genes containing a pollen-specific promoter from tomato (Lycopersicon esculentum) or the CaMV35S promoter were transiently expressed following their introduction into tobacco (Nicotiana tabacum) pollen using high velocity microprojectiles. Transient expression of the microprojectile-introduced genes in leaves and pollen was similar to that observed for these genes in stably transformed tobacco plants.

Journal Article↗
PubMed1989

Gametophytic and sporophytic expression of anther-specific genes in developing tomato anthers.

The tissue localization of transcripts corresponding to five anther-specific cDNA clones isolated from tomato was determined. Transcripts specified by three of the cDNA clones were first detectable in anthers containing mitotic-stage gametophytes and were localized to the gametophyte. Transcripts specified by the two other cDNA clones were not detectable until anthers had reached a later developmental stage; these transcripts were also localized to the (now bicellular) gametophytes. Transcript levels for all of the cDNAs increased during gametogenesis and reached maximal levels in mature pollen grains. These mRNAs persisted in in vitro-grown pollen tubes, concentrating toward the tips of the growing tubes. At flower maturity, transcripts specified by each of the cDNAs were also detected in the epidermal and endothecial cell layers of the anther wall. The spatial distribution of transcripts in the anther wall was confined to that region of the anther that surrounds the locule. Transcripts were not detected in the sterile tip of the anther or in the filament. mRNA levels for these cDNA clones were markedly reduced in the anthers of several independent male-sterile mutants of tomato. Our results provide evidence that these anther-specific cDNAs represent genes expressed in both the gametophytic and sporophytic phases of the plant life cycle. The patterns of mRNA accumulation observed support the hypothesis that the proteins encoded by these genes function during pollen development and pollen tube growth.

DNA↗
PubMed1989

5-Hydroxytryptamine uptake in oxygen radical-mediated acute lung injury.

Pulmonary endothelial cell function (ECF) studies have been shown to be a sensitive indicator of chronic lung injury. We attempted to correlate changes in 5-hydroxytryptamine (5HT) uptake with an acute oxygen radical-mediated lung injury in dogs. Beta-d glucose/glucose oxidase was injected intravenously in an experimental group (n = 10), while the control group (n = 5) received saline. 5HT uptake, measured using a multiple indicator dilution technique before and 20 min after injection, was calculated for both the percent total uptake and the peak extraction ratio of 5HT during a single passage through the lung. The mean pulmonary and systemic arterial pressures (PAP, SAP), total pulmonary resistance (TPR), extravascular lung water (EVLW), and wet-to-dry weight ratios were also determined. The experimental group showed an acute rise in PAP and TPR and a fall in SAP after the injection, all returning to normal by 20 min; total 5HT uptake fell from 81 +/- 2.3% to 47 +/- 6.5% (p = 0.0002) as did the peak extraction ratio from 0.87 +/- 0.013 to 0.44 +/- 0.066 (p = 0.0001). No change in 5HT uptake was observed in the control group. EVLW did not change in either group, but wet-to-dry weight ratio was elevated in the experimental group (5.21 +/- 0.12 versus 4.73 +/- 0.06, p less than 0.01). ECF studies of 5HT uptake appear to be a sensitive indicator of acute lung injury in this large-animal, oxygen radical-induced injury model.

Acute Disease↗
PubMed1988

Influence of collagen gel substratum on response to low-density lipoprotein by cultured human skin fibroblasts.

The effect of low-density lipoprotein (LDL) on accumulation of glycosaminoglycans (GAG) was compared in cultures of human skin fibroblasts on a conventional plastic substratum and in a native type I collagen gel. The 24-h incorporation of [3H]glucosamine and Na2(35)SO4 into GAG secreted into the medium or associated with the substratum and cell surface (SCA) was measured in cells at subconfluent densities. When cells were grown on plastic, 13-25% of the labeled GAG was in the SCA pool. Cells cultured within a collagen gel matrix incorporated three times more [3H]glucosamine and up to five times more [35S]sulfate into this pool. The addition of LDL (300 micrograms protein/mL) to the medium increased the level of total GAG incorporation of [3H]glucosamine by 40-50% and of [35S]sulfate by 15-20% on both substrata. For cells on plastic the relative increase in the medium and SCA pool was similar, whereas for cells in collagen gel the response to LDL was twice as great in the SCA pool as in the medium. The distribution of GAG types was unaffected by LDL; hyaluronic acid remained the principal GAG in the media pools of both substrata, heparan sulfate remained the main SCA GAG in cultures on plastic, and dermatan sulfate remained the dominant GAG in the SCA pool of collagen gel cultures. LDL degradation was measured at intervals up to 48 h after the addition of 125I-labeled LDL. The rate of accumulation of degraded LDL products was lower in collagen gel cultures, but the final levels achieved were the same in the two substrata. Concentrations of total cell cholesterol were similar, although the increases in free cholesterol induced by LDL were 26% greater in cells within collagen gel than in those on plastic. We conclude that fibroblasts grown within a collagen gel, as compared with those on a plastic substratum, (i) accumulate more GAG that remain attached to the substratum and cell surface; (ii) respond to LDL with a similar degree of increase in GAG accumulation, but more of the increase is found in the substratum and cell surface compartment; and (iii) accumulate more intracellular free cholesterol in response to LDL.

Cells, Cultured↗
PubMed1988

The fascia lata sling procedure for treating recurrent genuine stress incontinence of urine.

The fascia lata sling procedure has been used over the past 22 years in our unit for treating recurrent urinary stress incontinence when irreparably poor local support tissues were suspected. Sixty-nine patients had undergone one previous operation to correct urinary stress incontinence. One hundred one patients had two or more previous operations. The cure rate for the condition of genuine stress incontinence has been 100% in the last 148 cases and 98.2% overall. However, the cure rate for the symptom of urinary stress incontinence was 92.4%. There were only three sling failures in the entire series, occurring in the first 22 cases. Ten other patients had urinary incontinence with stress because of motor urge incontinence. The most troublesome postoperative problem has been delayed voiding.

Adult↗
PubMed1988

Intraurethral-intravesical cough-pressure spike differences in 267 patients surgically cured of genuine stress incontinence of urine.

Cough-pressure spike differences between the urethra and bladder were compared before and after surgery that cured genuine stress incontinence in 267 women. In 97.4% of 151 patients cured by a fascia lata sling procedure, the urethralvesical cough-pressure transmission ratio was greater than 100%, and in no case was it less than 100%. In 46.6% of 116 patients cured by anterior colporrhaphy, the cough-pressure transmission ratio was greater than 100%, and in 20.7% of the 116 patients, the transmission ratio was less than 100%. The 24 women in the latter group were cured by a sufficient increase in resting intraurethral pressure (to augment the maximal intraurethral closure pressure with stress) to maintain continence with increased intra-abdominal pressure. We believe that urethral kinking at the instant of increased intra-abdominal pressure with stress produced the greater than 100% cough-pressure transmission ratio seen in 201 (75.3%) of the 267 patients cured of genuine stress incontinence.

Cough↗
PubMed1987

Antiviral effect of 9-(1,3-dihydroxy-2-propoxymethyl)guanine against cytomegalovirus infection in a guinea pig model.

The antiviral activity of 9-(1,3-dihydroxy-2-propoxymethyl)guanine (DHPG) against guinea pig cytomegalovirus (GPCMV) was evaluated in guinea pig cell cultures and in Hartley guinea pigs. The 50% effective dose of DHPG against GPCMV replication in cell cultures was 71 microM. Ultrastructural studies revealed that DHPG inhibited the formation of viral cores and the production of nucleocapsids, enveloped virions and dense bodies, but the drug did not prevent the formation of virus induced intranuclear tubular structures. In vivo, guinea pigs inoculated intraperitoneally with GPCMV were treated with DHPG, 25 mg/kg subcutaneously, twice daily. Treatment was initiated 24 h after infection and continued for 7 days. During the acute infection, the average body weights of DHPG-treated, virus infected guinea pigs were approximately 14% lower than the sham-treated counterparts on day 10, 11 and 13 post-virus inoculation. Virus infectivity titers were higher in the lungs of DHPG-treated guinea pigs on day 10 than the sham-treated ones. Although there was no significant difference on histopathologic lesions in the spleen, liver and lungs of the drug-treated and the sham-treated guinea pigs, DHPG treated animals appeared to have fewer virus-induced lesions or inclusions in the kidneys and salivary glands than the sham-treated ones. In addition, virus infectivity titers in the salivary gland of DHPG treated guinea pigs were consistently lower than the sham-treated animals.

Acyclovir↗
PubMed1987

Cyclophosphamide immunosuppression during lymphotropic herpesvirus infection in the guinea pig model. A histopathologic and virologic study.

Guinea pigs infected with lymphotropic herpesvirus (GPHLV) were given the immunosuppressive agent cyclophosphamide (Cy). All Cy-treated animals revealed the expected lymphoid depletion of spleen and lymph node B zones. Acute GPHLV infection of Cy-treated animals resulted in increased blood and spleen leukocyte viral infectivity titers and lymphoid tissue lesions containing cells positive for GPHLV antigen and intranuclear inclusions. During latent GPHLV infection, Cy treatment resulted in declining leukocyte viral infectivity titers without pathologic lesions. Morphologic data suggest that tissue histiocytic cells may be involved in the productive viral infection observed in Cy-immunosuppressed animals during acute GPHLV infection. During latency, however, infectious virus appears restricted to a Cy-sensitive, probably lymphoid, cell. This animal model appears useful for the study of lymphotropic viral infection during immunosuppression.

Animals↗
PubMed1985

Preserved irradiated homologous cartilage implants in canine eyelids.

Preserved irradiated homologous costal cartilage implants were placed in six canine lower lids for a period of 7-12 weeks. The three implants placed under a covering of conjunctiva simulating current clinical technique were well tolerated and demonstrated little change. Exposed implants produced obvious clinical inflammation and two of three exposed grafts disappeared during the 4- to 5-week interval. The single exposed implant that was retained demonstrated partial epithelialization but suffered extensive absorption and remodeling.

Animals↗
PubMed1984

Lymphoproliferative changes induced by infection with a lymphotropic herpesvirus of guinea pigs.

The effects of experimental infection with guinea-pig herpes-like virus (GPHLV) on hematologic and histopathologic parameters were studied in Hartley strain guinea pigs inoculated intraperitoneally with 10(3) or 10(6) 50% tissue culture infectious doses of GPHLV. The total leukocyte count, the percentage of cells that were mononuclear, the number of spontaneous rosette-forming cells, and hematocrit values were determined after various intervals. Cells from spleens, cervical lymph nodes, and bone marrow of animals killed at various times were assayed for infectious virus, and tissues were prepared for histological examination. Spleen-to-body weight ratios were also determined. GPHLV infection resulted in a mild, asymptomatic, transient lymphoid hyperplasia. The infected animals experienced a relative and absolute peripheral-blood lymphocytosis lasting for seven to eight weeks. The spleens showed evidence of immune stimulation for four to six weeks. Despite the transient nature of the histological and peripheral-blood changes, virus was recovered by cocultivation from the spleen, bone marrow, and lymph nodes for up to eight months (the time of the last test). Infectivity titers were highest in the B-lymphocyte subpopulation during latent infection. These findings of GPHLV persistence after a mild, acute mononucleosis-type syndrome were compared with observations during human Epstein-Barr viral infection.

Animals↗
PubMed1984

Regressing atypical histiocytosis. Report of a case.

A patient with a pseudomalignant, histiocytic dermal lesion is reported. Despite a torpid course, the lesion was considered on histologic grounds by several consultants to be malignant. It appears to be distinct from previously reported pseudosarcomas or pseudolymphomas and most closely resembles a recently described condition termed "regressing atypical histiocytosis." The clinical and histopathologic features are summarized.

Histiocytes↗
PubMed1984

Interaction of high and low density lipoproteins on glycosaminoglycan secretion by human vascular smooth muscle cells and fibroblasts.

Low density lipoprotein (LDL) increased secretion of glycosaminoglycans (GAG) and the cell cholesterol content of proliferating fibroblasts and smooth muscle cells in culture; with increasing cell density the GAG effect decreased, but the cholesterol effect did not. High density lipoprotein (HDL, d greater than 1.063) decreased GAG secretion by slowly proliferating cells; when cells were actively proliferating, HDL alone did not affect GAG secretion, but it inhibited the increase caused by LDL. Thus HDL appeared to influence GAG secretion by two separate mechanisms, an inhibition which was overcome by rapid proliferation and an anti-LDL effect. HDL2 (d = 1.063-1.100) partially reproduced the latter effect. In addition, HDL, HDL2, and HDL3 increased cell cholesterol; the ability of LDL to increase cholesterol was correspondingly reduced in the presence of HDL and its subfractions, suggesting that they act by common mechanisms.

Acetates↗
PubMed1982

Treatment of urinary stress incontinence with anterior colporrhaphy.

The results of treating 105 patients with urinary stress incontinence using anterior colporrhaphy have been reviewed. When polyglycolic suture material and a suprapubic catheter were used, the cure rate was 90.9%, which is comparable to other procedures that are associated with greater morbidity. the problem of comparing the results of one procedure with those of another and results from one center with those of another is discussed. The authors maintain that the surgical objective in treating urinary stress incontinence is to create differentially better support to the urethra, or to a portion of the urethra, so that a mechanical kinking effect can occur synchronously with stress in the urethra to offset pressure increase in the bladder, thereby maintaining urinary continence.

Female↗
PubMed1979

Conjugate lateral eye movements of "repressors" and "sensitizers" under threat and non-threat conditions.

Investigated the relationship between repression-sensitization and conjugate lateral eye movement (CLEM) tendencies under ego-threat and control conditions. Fifty-one right-handed college males were separated into repressors, sensitizers, or a middle group and were interviewed under a condition intended to produce ego-threat or a neutral condition. Bland and mildly intimate questions were asked of all Ss. Contrary to expectation, repression-sensitization and threat condition were unrelated to eye movement direction. A significant increase in left eye movement was found in response to mildly intimate questions, compared to neutral questions. Results are discussed with reference to earlier research on CLEM and to the cerebral hemispheric dominance theory of the effect.

Adult↗