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Biomedical subjects

G W Smith

Publications and source records attributed to G W Smith.

At least 55 records · Page 3Linked to original sources
PubMed1997

Ankylosing spondylitis and secretor status: a re-evaluation.

Non-secretion of ABO blood group substances in body fluids is associated with susceptibility to some bacterial infections. Non-secretors were previously found to be over-represented in patients with ankylosing spondylitis (AS) (49%) compared to controls (27%). Re-evaluation of secretor status in a population of 92 AS patients and 103 controls revealed identical proportions of non-secretors (28%). Of 43 patients studied in both surveys, 6/22 typed initially as non-secretors proved to be secretors using both haemagglutination inhibition assay (HAI) and enzyme-linked immunosorbent assay (ELISA) techniques. Loss of secreted blood group antigens in the saliva is the cause of this mis-typing. Careful attention to the method of collection, handling and preservation of saliva specimens is essential for accurate assessment of secretor status. Therefore, there is no link between secretor status and AS.

ABO Blood-Group System↗
PubMed1997

Faecal flora in spondyloarthropathy.

Enterobacteria, in particular Klebsiella spp., have been implicated in the aetiopathogenesis of ankylosing spondylitis. A comprehensive examination of the faecal flora of 82 patients with ankylosing spondylitis, either primary (67), or in association with inflammatory bowel disease (4), reactive arthritis (6) or psoriatic arthritis (5), was performed and compared with that of a control population (36) of healthy individuals. The range of flora identified was similar in both populations and there was no increased isolation rate of Klebsiella or other proposed arthritogenic organism in those with spondyloarthropathy. In those patients in whom Klebsiella was identified, its presence was not related to disease activity, the erythrocyte sedimentation rate or C-reactive protein.

Acute-Phase Reaction↗
PubMed1997

Changes in messenger ribonucleic acid encoding luteinizing hormone receptor, cytochrome P450-side chain cleavage, and aromatase are associated with recruitment and selection of bovine ovarian follicles.

The objective of this study was to investigate changes in expression of mRNAs encoding FSH receptor (FSHr), LH receptor (LHr), cytochrome P450 side-chain cleavage (P450(scc)), cytochrome P450 17alpha-hydroxylase (P450(c17)), and cytochrome P450 aromatase (P450(arom)) during recruitment and selection of bovine ovarian follicles. Dairy heifers (4-5 per group) were ovariectomized at 12, 24, 36, 48, 60, 72, 84, or 96 h after initiation of the first follicular wave following estrus as determined by ultrasonography (Time 0 = initiation of follicular wave; mean +/- SEM = 42.0 +/- 2.6 h after estrus). Expression of mRNAs encoding FSHr, LHr, P450(scc), P450(c17), and P450(arom) was detected by in situ hybridization and quantified by image analysis. Antral follicles were classified as healthy or atretic. Healthy follicles expressed higher (p < 0.01) amounts of mRNAs for gonadotropin receptors and steroidogenic enzymes than did atretic follicles, and expression of LHr, FSHr, P450(scc), P450(c17), and P450(arom) increased (p < 0.01) with follicular size and stage of the follicular wave. Expression of mRNAs for P450(scc), P450(arom), and LHr was time- and size-dependent during recruitment and selection. During recruitment, expression of mRNAs for P450(scc) and P450(arom) was first detected in granulosa cells of 16 of 21 of the follicles 4-6 mm in diameter at 12 h. At 24 and 36 h, almost all follicles 6-9 mm in diameter, but not those 4-5 mm in diameter, expressed both P450(scc) and P450(arom) mRNA in the granulosa cells. At 48 h and thereafter, P450(scc) and P450(arom) mRNA were expressed predominantly in one healthy large follicle per cow with a few exceptions. Expression of LHr mRNA was first detected in granulosa cells at 36 h and was always found in granulosa cells of one follicle > or = 8 mm per cow with exception of one cow at 36 h (no expression) and another two cows, one each at 36 and at 84 h (expression in 2 follicles). In addition, LHr mRNA expression in the granulosa cell layer was limited to follicles that also expressed mRNAs for P450(scc) and P450(arom) in the granulosa cells. In summary, follicular recruitment in cattle was associated with expression of P450(scc) and P450(arom) mRNA within granulosa cells, and the process of follicular selection was associated with initiation of LHr mRNA expression in granulosa cells.

Animals↗
PubMed1997

Expression of messenger ribonucleic acid (mRNA) encoding 3beta-hydroxysteroid dehydrogenase delta4,delta5 isomerase (3beta-HSD) during recruitment and selection of bovine ovarian follicles: identification of dominant follicles by expression of 3beta-HSD mRNA within the granulosa cell layer.

The objective of the present study was to examine changes in expression of mRNA encoding 3beta-hydroxysteroid dehydrogenase delta4,delta5 isomerase (3beta-HSD) during recruitment and selection of bovine ovarian follicles. Dairy heifers (4-5/time period) were ovariectomized at 12, 24, 36, 48, 60, 72, 84, or 96 h after initiation of the first follicular wave (Time 0) following estrus. Expression of 3beta-HSD mRNA was localized by in situ hybridization and quantified by image analysis. Expression of 3beta-HSD mRNA was first detected in theca interna cells of preantral follicles with a well-developed theca layer and in granulosa cells of follicles > or = 8 mm in diameter. Regardless of stage of follicular wave, expression of 3beta-HSD mRNA in granulosa cells of follicles > or = 8 mm was correlated with follicular size (r = 0.665; p < 0.01). The 36-h time period appeared to be a transition period for selection since dominant follicles were detected by size and expression of 3beta-HSD mRNA in some cows but not in others. By 48 h after wave initiation, dominant follicles could be identified by both size and expression of 3beta-HSD mRNA. Expression of mRNA for 3beta-HSD in theca cells was higher (p < 0.05) at 24 h than at 12 h and remained elevated thereafter through 96 h. In contrast to theca cells, expression of mRNA for 3beta-HSD was undetectable within granulosa cells at 12 and 24 h. At 36 h, 3beta-HSD mRNA was expressed in granulosa cells of healthy follicles > or = 8 mm, and expression was higher (p < 0.05) at 48 h compared with 36 h. Expression of 3beta-HSD mRNA levels increased further in granulosa cells (p < 0.05) at 84 and 96 h compared to 48 h. Upon detection of mRNA for 3beta-HSD in granulosa cells, high levels of expression were always found in one (dominant) follicle/cow with the exception of two cows at 36 and 84 h that expressed 3beta-HSD mRNA in two large healthy follicles. Expression of 3beta-HSD mRNA was also detectable in granulosa cells of a few large atretic follicles in which remnant granulosa cells appeared to be luteinized. Healthy follicles expressed higher (p < 0.05) levels of 3beta-HSD mRNA in both theca and granulosa cells than did atretic follicles. Expression of 3beta-HSD mRNA in theca cells was higher (p < 0.01) in dominant follicles than in other subordinate healthy follicles. These results indicate that only selected dominant follicles express 3beta-HSD mRNA within granulosa cells, and expression increased in both thecal and granulosa cells during the follicular wave. Therefore, expression of 3beta-HSD mRNA within granulosa cells may be associated with the mechanism of selection of the dominant follicle during a follicular wave and may be required for maximum steroid production during follicular dominance.

Animals↗
PubMed1997

Control of extracellular matrix remodelling within ovarian tissues: localization and regulation of gene expression of plasminogen activator inhibitor type-1 within the ovine corpus luteum.

Extensive extracellular matrix remodelling occurs within the lifespan of the corpus luteum, particularly during corpus luteum formation and regression. A major mechanism for the regulation of extracellular matrix remodelling is via local production of specific proteinase inhibitors, such as the serine proteinase inhibitor plasminogen activator inhibitor type-1 (PAI-1). The objective of the present study was to characterize the localization, ontogeny and regulation of PAI-1 expression within ovine corpora lutea. Urokinase binding activity was detected within medium conditioned by ovine luteal cells. Production of PAI-1 by ovine luteal cells was confirmed by immunoprecipitating it from labelled proteins in culture medium. mRNA encoding PAI-1 was present within developing (day 3), mature (day 10) and regressing (30 h after prostaglandin F2 alpha injection on day 10 after the onset of oestrus) corpora lutea as demonstrated by in situ hybridization. The ontogeny of PAI-1 mRNA expression was characterized within corpora lutea collected on days 3, 7, 10, 13 and 16 after the onset of oestrus (n = 4, 4, 4, 3 and 4, respectively). Expression of PAI-1 mRNA did not differ during the luteal phase (P = 0.06), although a trend for an increase in the amount of PAI-1 mRNA was observed on day 16. Expression of PAI-1 mRNA was also examined during luteal regression in corpora lutea collected 0, 6, 12, 24 and 36 h after injection of prostaglandin F2 alpha on day 10 after the onset of oestrus (n = 4 at each time). Relative PAI-1 mRNA concentrations changed significantly during luteolysis induced by prostaglandin F2 alpha (P = 0.0002). Administration of prostaglandin F2 alpha resulted in a transient sevenfold increase in PAI-1 mRNA 6 h after injection (P = 0.0001) but by 12 h the amounts had returned to values similar to those detected on day 10. We conclude that PAI-1 is a major secretory product of ovine luteal cells and that a transient increase in PAI-1 mRNA occurs during luteolysis induced by prostaglandin F2 alpha. PAI-1 probably plays a key local role in the control of extracellular proteolysis during the luteal phase.

Animals↗
PubMed1996

Cardiovascular effects of fumonisins in swine.

Fumonisins, mycotoxins produced by Fusarium moniliforme, induce hepatic damage and acute lethal pulmonary edema in swine. We examined the cardiovascular effects of short-term fumonisin exposure in anesthetized and conscious male cross-bred pigs weighing 30-36 kg. Culture material containing fumonisins at < or = 20 mg/kg/day (fumonisin B1 and B2 backbone) was added to the feed of treated pigs (n = 5) for 7 days, while control pigs (n = 5) were fed a diet free of fumonisins. On Day 8, pigs were anesthetized with halothane and instrumented with Swan-Ganz catheters to facilitate hemodynamic measurements. Mean pulmonary artery pressure, central venous pressure, heart rate, cardiac output, and electrocardiographic variables were recorded and stroke volume was calculated. All measurements were repeated at least 18 hr after recovery from anesthesia. Pigs fed fumonisins had a significant increase in mean pulmonary artery pressure, accompanied by decreased heart rate, cardiac output, and mixed venous oxygen tension. The electrocardiogram was normal, and there was no evidence of pulmonary edema formation either histologically or by altered lung wet/dry weights. This study suggests that pulmonary hypertension caused by hypoxic vasoconstriction may be associated with the pulmonary edema observed in fumonisin toxicity.

Animals↗
PubMed1996

Cardiovascular responses to short-term fumonisin exposure in swine.

The cardiovascular effects of the mycotoxin fumonisin were examined in male cross-bred pigs fed 20 mg/kg of fumonisin-containing culture material for 7 days. On Day 8, pigs were anesthetized with halothane and surgically catheterized. Cardiovascular measurements and blood gas analyses were obtained during halothane anesthesia and 18 hr after recovery from anesthesia. Pigs fed fumonisin had significant (p < 0.05) decreases in maximal rate of change of left ventricular pressure, heart rate, cardiac output, and mean aortic pressure, a significant increase in mean pulmonary artery pressure and pulmonary vascular resistance, and no change in left ventricular end-diastolic pressure, pulmonary wedge pressure, and central venous pressure. Treated pigs also had significant decreases in both arterial and mixed venous blood O2 tension, and systemic oxygen delivery, but significantly increased oxygen consumption and oxygen extraction ratio. These results suggest that fumonisin increases oxygen consumption and is a negative inotropic and chronotropic agent in pigs. Because fumonisin is a naturally occurring inhibitor of the enzyme sphingosine N-acyltransferase, thereby increasing sphingosine concentrations in vivo, we speculate that the observed cardiovascular effects were mediated in part by a fumonisin-induced increase in tissue sphingosine concentrations.

Administration, Oral↗
PubMed1996

Ontogenies of messenger RNA encoding tissue inhibitor of metalloproteinases 1 and 2 within bovine periovulatory follicles and luteal tissue.

Tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1 and TIMP-2) are important regulators of extracellular matrix remodeling and also possess growth factor activity. The objective of these studies was to characterize TIMP-1 and TIMP-2 mRNA expression by bovine periovulatory follicles/ corpora hemorrhagica (Experiment 1) and luteal tissue (Experiment 2). In Experiment 1, beef heifers (n = 27) were ovariectomized at-16 (n = 6), 0 (n = 5), 8 (n = 3), 16 (n = 4), 24 (n = 4), or 48 (n = 5) hr relative to a gonadotropin-releasing hormone induced gonadotropin surge (40 hr after prostaglandin F2 alpha-induced luteolysis). Total cellular RNA was isolated from the large steroidogenically active follicle or corpus hemorrhagicum obtained from each animal, and the expression of TIMP-1 and TIMP-2 mRNA was subsequently examined by northern and dot blot analysis. The expression of TIMP-1 or TIMP-2 mRNa did not differ in preovulatory follicles collected at -16 vs. 0 hr. Concentrations of both TIMP-1 and TIMP-2 mRNA (picograms per microgram of tissue DNA) were increased (P < 0.05) at 8 hr postgonadotropin surge, had declined to presurge levels by 24 hr (P < 0.05), and were increased (P < 0.05) in corpora hemorrhagica collected at 48 hr after a gonadotropin surge. In Experiment 2, corpora lutea were collected from beef heifers on Days 4, 10, 15 (n = 4 each), or 19 (n = 3) postestrus (Day 0 = estrus). Concentrations of TIMP-1 mRNA (picograms per microgram of tissue DNA) were greater in corpora lutea collected on Day 4 (P < 0.05) vs. Day 10, 15, or 19. Concentrations of TIMP-2 mRNA increased (P < 0.05) from Day 4 to 15 and decreased (P < 0.05) by Day 19. We conclude that: 1) during the periovulatory period, the ontogenies of TIMP-1 and TIMP-2 mRNA expression are similar, whereas 2) during luteal phase, TIMP-1 mRNA expression is maximal during the early luteal phase, whereas concentrations of TIMP-2 mRNA peak during the midluteal phase. TIMP-1 and TIMP-2 may play important roles in the regulation of extracellular matrix remodeling during the periovulatory period and the subsequent luteal phase.

Animals↗
PubMed1996

Ontogeny and regulation of luteinizing hormone receptor messenger ribonucleic acid within the ovine corpus luteum.

Although LH regulates corpus luteum (CL) function and LH receptor (LHR) binding has been characterized within ovine CL, changes in LHR mRNA expression have not been documented. The objectives here have been to assess relative amounts of LHR mRNA in ovine CL throughout the estrous cycle and during luteolysis by ribonuclease protection analysis. In experiment 1, LHR mRNA was quantified within CL collected on Days 3, 7, 10, 13, and 16 post-estrus (n = 3, 4, 4, 3, and 4, respectively). LHR mRNA differed throughout the luteal phase (p < 0.01), with higher concentrations found during the midluteal phase (Days 10 and 13) than during the early (Day 3) or late (Day 16) luteal phase (p < or = 0.05). In experiment 2, LHR mRNA content was determined within pools of Day 10 small (n = 4) or large (n = 4) luteal cells. Relative amounts of LHR mRNA were not different (p = 0.1) in small (2.23 +/- 0.22 relative units) vs. large (1.62 +/- 0.22 relative units) luteal cells. In experiment 3, CL were collected at 0, 6, 12, or 24 h after injection of 15 mg prostaglandin F2 alpha) on Day 10 post-estrus (n = 4, 4, 3, and 4, respectively). LHR mRNA content fell during PGF2 alpha-induced luteolysis (p < 0.002), decreasing significantly by 6 h (1.76 vs. 1.10 relative units; p < or = 0.05). By 24 h, levels were approximately 60% of those detected within 0-h controls (1.76 vs. 0.79 relative units; p < 0.05). These results indicate that changes in LHR mRNA during the luteal phase correlates well with previously reported changes in LHR binding. After PGF2 alpha administration, LHR mRNA falls earlier than the reported drop in LHR binding sites occurs.

Animals↗
PubMed1996

Characterization of ovine stem cell factor messenger ribonucleic acid and protein in the corpus luteum throughout the luteal phase.

Stem cell factor (SCF) is a growth factor known to have profound effects on the proliferation, migration, differentiation, and survival of numerous cell types, including those of the ovary. The objectives of the present study were to identify and characterize expression of this growth factor in the ovine corpus luteum (CL). A 952-bp cDNA was amplified from Day 3 (Day 0 = estrus) ovine luteal total cellular (tc) RNA by reverse transcriptase-polymerase chain reaction and determined to encode SCF. Northern analysis of Day 10 luteal poly(A)+ RNA indicated one major transcript of approximately 6.5 kb. SCF mRNA was localized within Day 3 and Day 10 CL by in situ hybridization and was expressed throughout luteal tissue on both days examined. To asses expression throughout the luteal phase, SCF mRNA was quantified by ribonuclease protection assay in tcRNA collected on Day 3, 7, 10, 13, and 16; values did not differ across days (p > 0.10). Similarly, SCF mRNA was quantified in tcRNA isolated from pools of Day 10 large and small steroidogenic cells (n = 4 and 3, respectively); levels did not differ (p > 0.10) between cell types. In addition, SCF protein was detected in CL on Days 3 and 10, and was expressed in a cell-specific manner in cells with morphological characteristics of large and small luteal cells. These data indicate that SCF may be involved in communication among steroidogenic cells and/or between steroidogenic and nonsteroidogenic cells of the CL.

Amino Acid Sequence↗
PubMed1996

Differential gene expression within the ovine corpus luteum: identification of secreted protein acidic and rich in cysteine as a major secretory product of small but not large luteal cells.

Limited information is available regarding secretory proteins of the corpus luteum (CL), and the potential local role these proteins may play in control of luteal function. An ovine small luteal cell complementary DNA library was immunologically screened with a polyclonal antiserum generated against small cell secretory proteins. A relatively abundant complementary DNA (approximately 2.1 kb) encoding a calcium binding glycoprotein Secreted Protein Acidic and Rich in Cysteine (SPARC) was isolated. Production of SPARC protein by ovine luteal cells was confirmed by immunoprecipitating it from labeled culture medium. Expression of SPARC messenger RNA (mRNA) was examined within CL collected on days 3, 7, 10, 13, and 16 post estrus (n = 4, 4, 4, 3, and 4 respectively), and within pools of purified small (n = 3) and large (n = 4) luteal cells by Northern and dot blot analysis. Amounts of SPARC mRNA increased during the early luteal phase, peaked by day 7 (P < 0.05) and subsequently declined on days 10 and 13 (P < 0.05). SPARC mRNA content was significantly higher in the small than in the large cells (P < 0.003). In situ hybridization showed that SPARC mRNA was localized to the thecal layer of Graafian follicles and to day 3 and day 10 CL. Within CL, immunohistochemistry indicated that SPARC protein was associated with small luteal cells (spindle shaped, avg = 17 microM in diameter) but not with large cells. This specific localization to small cells was confirmed by colocalization of SPARC with 3 beta-hydroxysteroid dehydrogenase. We conclude that SPARC is a major secretory product of small steroidogenic luteal cells of the ovine CL. As SPARC is known to modulate many aspects of tissue reorganization, expression by small luteal cells may play a role in regulation of CL maturation.

3-Hydroxysteroid Dehydrogenases↗
PubMed1996

Outcome following colon surgery in the octagenarian.

The results of colon surgery in all individuals aged 80 years or greater at one teaching institution during the 1987-1993 time period were reviewed. Sixty patients, ranging in age from 80 to 92 years, underwent 41 elective operations and 21 emergency procedures. Emergency procedures resulted in death or a major complication in over one-half of patients, and only six were ultimately able to return home. Conversely, elective procedures were relatively well tolerated, and 31 of 37 survivors returned immediately to independent living (P = 0.006). Mortality was 33.3 per cent in emergency cases versus 9.8 per cent in elective operations (P < 0.03). The occurrence of a postoperative complication increased the length of stay by an average of 12 days. These data suggest that elective colon surgery in the elderly produces results little different from the population at large. Conversely, emergency operations are associated with a high morbidity and mortality rate. Age alone should not be a determining factor in who undergoes an elective colon operation. Greater efforts should be made to screen elderly individuals to limit emergency surgery.

Age Factors↗
PubMed1996

Will stereotactic breast biopsy achieve results as good as current techniques?

Stereotactic procedures recently have been advocated to replace most needle localization and open biopsy procedures. In order to provide a baseline for comparison at our institution, a retrospective review of our results over the last 3 years was performed. During this time period, 496 biopsies were performed in 480 patients. Needle localization was done in 311 cases, whereas the remaining 185 biopsies were done for palpable masses. There were no significant differences in either the positive rate (19.0% vs 13.5%) or the infection rate (2.6% vs 1.6%) in the two groups. Follow-up of all patients has revealed no missed carcinomas and no referrals to a plastic surgeon for a poor cosmetic result. Current breast biopsy techniques yield good results, with acceptably low morbidity rates. Given that approximately one in five needle localization biopsies detects a malignancy, a negative result following a stereotactic biopsy may not preclude a needle localization procedure. It is therefore unlikely that stereotactic procedures will lead to an overall decrease in health care costs. Surgeon involvement will be crucial to assure best and most cost-effective results.

Adolescent↗
PubMed1996

Effects of fumonisin-containing culture material on pulmonary clearance in swine.

OBJECTIVE: To determine the potential effects of feeding tumonisin-containing culture material on the pulmonary clearance of blood-borne particulates and bacteria in swine. ANIMALS: 21 healthy male pigs randomly assigned to control and treated groups. PROCEDURE: Control pigs were fed a standard grower ration while culture material containing fumonisins (20 mg of hydrolyzed fumonisin B1/kg of body weight/d) was added to the feed of treated pigs for 7 days. On day 8, pigs were anesthetized with halothane and catheterized, using a sterile cut-down procedure. 18 hours after recovery from anesthesia, Monastral Blue or Pseudomonas aeruginosa was infused into the right atrium of treated and control pigs for 30 minutes and pulmonary clearance was determined. RESULTS: Pigs that were fed fumonisin-containing culture material had a significantly (P < 0.05) decreased ability to clear Monastral Blue and P aeruginosa. Ultrastructural examination of the lung indicated that uptake of copper pigment by pulmonary intravascular macrophages was decreased in treated pigs. CONCLUSIONS AND CLINICAL RELEVANCE: Fumonisins, even when fed to pigs at sub-lethal concentrations, can inhibit pulmonary intravascular macrophages from removing particulate matter and bacteria from the circulation, thus potentially predisposing swine to infectious disease.

Animal Feed↗
PubMed1996

General surgical care in the nursing home patient: results of a dedicated geriatric surgery consult service.

BACKGROUND: Although recent interest has centered on diseases that require operation in the elderly, few data are available about the effects of surgical intervention on the frail nursing home patient. STUDY DESIGN: A longitudinal study was conducted of the nature of illness requiring operation and intervention in residents of a geriatric center associated with a tertiary care medical center. A unique consult service for the patients was established and all referrals were prospectively followed up. RESULTS: The actuarial 18-month survival of patients referred was 35 percent. Although maintenance care (e.g., decubitus ulcer, stoma, and enteral tube care) made up a substantial number of referrals (32.5 percent), common surgical diseases of the abdomen, breast, and vascular system were routinely encountered (55 percent). In patients undergoing surgery, the 30-day mortality rate was 8.5 percent, and the complication rate 9.4 percent. Although patients undergoing major abdominal and vascular procedures had a higher complication rate (17.6) percent than those undergoing lesser procedures (6.3 percent, p = 0.05), there was no difference in the 30-day mortality (9.8 compared with 6.3 percent, respectively) or 18-month actuarial survival (33 compared with 32 percent, respectively) rates. The overall actuarial survival was adversely affected by the presence of coronary artery disease (relative risk [RR], 3.27) and dementia (Mini-Mental State Examination score less than 24; RR, 2.39) and age older than 70 years (RR, 2.03). The overall survival was unaffected by the actual need for operation, the magnitude of the procedure performed, gender, the number of comorbid conditions, and the preoperative code (resuscitative) status. CONCLUSIONS: Although nursing home patients referred for surgical intervention have poor survival rates, the use of surgical procedures does not adversely affect overall survival. This supports the idea that care for this patient population is not futile, and quality of life, patient dignity, and relief of suffering can provide a alternative to curative therapy.

Actuarial Analysis↗
PubMed1995

Spontaneous hemothorax caused by a chest wall chondrosarcoma.

A 48-year-old man who presented with chest pain was found to have a spontaneous hemothorax caused by a large grade II chondrosarcoma. This was diagnosed on the basis of the findings from thoracotomy. After chest tube drainage of the hemothorax, the tissue obtained by two computed tomography-guided biopsies of a residual mass did not yield findings that allowed diagnosis of the tumor. This unusual case illustrates the importance of a systematic workup whenever a spontaneous hemothorax is encountered.

Bone Neoplasms↗
PubMed1995

Expression of follicle-stimulating hormone and luteinizing hormone receptor messenger ribonucleic acids in bovine follicles during the first follicular wave.

The objective of the present study was to characterize expression of mRNAs encoding FSH and LH receptors during follicular development and at different stages of the first follicular wave in cattle. Following estrus, groups of heifers (3-5 per group) were ovariectomized on the day of initiation of the first follicular wave (as determined by ultrasonography; Day 0), or on Days 2, 4, 6, 8, or 10 after initiation of the first wave. FSH and LH receptor mRNAs were detected within follicles > or = 4 mm and in some smaller follicles by in situ hybridization and were quantified by image analysis. FSH receptor mRNA was expressed in granulosa cells of all growing follicles, starting in some follicles with only one layer of granulosa cells. Irrespective of day of the follicular wave, the level of expression of FSH receptor mRNA in granulosa cells of healthy antral follicles ranging from 0.5 to 14 mm in diameter did not vary significantly with follicular size (r = 0.02, p > 0.10). Expression of LH receptor mRNA was first observed in theca interna cells of follicles shortly after antral formation. Irrespective of day of the follicular wave, the levels of LH receptor mRNA in theca interna cells of healthy antral follicles ranging from 0.5 to 14 mm increased with follicular size (r = 0.39, p < 0.01). In granulosa cells, LH receptor mRNA was expressed only in healthy follicles > 9 mm in diameter and was first observed in the dominant follicles collected on Day 4. Expression of mRNA for LH receptor, but not for FSH receptor, changed (p < 0.01) with the stage of the first follicular wave.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗