Allele-specific interactions between ttg and gl1 during trichome development in Arabidopsis thaliana.

Trichome development in Arabidopsis thaliana is a well-characterized model for the study of plant cell differentiation. Two genes that play an essential role in the initiation of trichome development are GL1 and TTG. Mutations in either gene prevent the initiation of most trichomes. The GL1 gene encodes a myb-related transcription factor. Mutations in TTG are pleiotropic, affecting anthocyanins, root hairs, and seed coat mucilage in addition to trichomes. Six ttg alleles were examined and shown to form a hypomorphic series. The severity of all aspects of the ttg phenotype varied in parallel in this allelic series. The weakest allele, ttg-10, causes frequent clusters of adjacent trichomes, suggesting a role for TTG in inhibiting neighboring cells from choosing the trichome fate. This allele results from a mutation in the 5'-untranslated region of ttg and creates an out-of-frame upstream AUG codon. The ttg-10 allele shows several unusual genetic interactions with the weak hypomorphic gl1-2 allele, including intergenic noncomplementation and a synthetic glabrous phenotype. These interactions are specific for the gl1-2 allele. The implication of these results for current models of trichome development is discussed.

Observer variation in quantitative assessment of rheumatoid arthritis Part II. A simplified scoring system.

A new and more comprehensive simplified scoring system to provide quantitative assessment of radiographic findings in rheumatoid arthritis was studied by six observers with different levels of expertise. Since the observers, film set, and joints scored were the same as in a prior study of a more detailed scoring method, a precise comparison of the results was made. Interobserver variation with the simplified scoring system was small; there were highly significant correlations of the total radiographic scores for all observers (R = .898-.978, P less than .001). There were highly significant correlations between scores obtained with the simplified scoring system and those obtained with the more detailed method (R = .920-.955, P less than .001). When the same joints were evaluated by the two methods, a significantly greater number of possible observations could be scored with the simplified scoring system than with the more detailed method (X2 = 131.07, P less than .001). The simplified scoring system required 2.3 times less time to use in the hands of experienced observers.

Observer variation in quantitative assessment of rheumatoid arthritis. Part I. Scoring erosions and joint space narrowing.

Six observers, including two bone and joint radiologists, two general radiologists, and two senior radiology residents, compared scores to quantitate radiographic findings in the hands and wrists of patients with rheumatoid arthritis. In the scoring system used, erosions and joint-space narrowing are graded separately. This scoring system differs from other methods in that equivocal findings are not scored, while ankylosis, subluxation, and dislocation are scored, and data from postoperative joints are included. Total radiographic scores were highly significantly correlated for all observers (R = .908-.958, P less than .001), as were subtotal scores for erosions (R = .723-.931, P less than .001) and joint-space narrowing (R = 0.843-0.966, P less than .001). Analysis of proximal interphalangeal, metacarpophalangeal, and wrist-joint scores showed highly significant correlations for all observers in each location. Highly significant correlations were found among three separate readings of two bone and joint radiologists (R = .950-.961, P less than .001). This scoring system provides highly consistent and reproducible results, even in the hands of less experienced observers.

Vicarious excretion of contrast medium in patients without azotemia.

Although excretion of urographic iodinated contrast agents via the biliary and gastrointestinal tract is not uncommon in patients with renal insufficiency, such vicarious excretion is unusual in the presence of normal renal function. The observation of such vicarious excretion in 2 patients with acute unilateral ureteral obstruction and no azotemia is reported in conjunction with review of the appropriate literature and suggestion of possible etiologies.

Advantages of nonionic contrast agents in adult urography.

Nonionic radiographic contrast agents have a reported advantage of decreased contrast osmolality. Before clinical significance can be attributed to this lower osmolality, an observed difference must be documented. In a randomized double-blind study with 55 patients, Iohexol, a new nonionic contrast agent, is compared with Renografin 60 for use in adult urography. Hemodynamic parameters, serum and urine chemistries, including osmolality, were recorded before and after contrast injection. Radiographic quality and adverse reactions were recorded. This study focused on the change in urine osmolality (delta Osm) from pre- and post-injection urine specimens. The group receiving nonionic contrast agents had an average delta Osm of 65 mOsm/L while those receiving the ionic agent had an average delta Osm of 120 mOsm/L. This significant difference in urine osmolality is discussed with respect to the observed advantage in radiographic quality and the lower incidence of adverse reactions noted in the group receiving nonionic contrast material.

Ureteral abnormalities in women with endometriosis.

High-volume intravenous urography was performed in 63 women with surgically proven endometriosis. Subtle abnormalities were found in 15.9% of these women. No patient had urologic symptoms, and there was no evidence of hydroureter or ureteral obstruction on the IVP. Long-term follow-up study will be required to determine whether or not these lesions will progress and cause ureteral obstruction.

Selective fallopian tube cannulation: initial experience in an infertile population.

We have studied a group of 19 patients presenting with proximal tubal occlusion. Seventy-three percent (22/30) of tubes attempted were successfully cannulated. Sixty-two percent (5/8) of tubes remained patent in limited follow-up at 3 to 6 months. We conclude that selective fallopian tube cannulation may provide an alternative to microsurgical tubal anastomosis in selected patients.

Diagnostic imaging of fertility disorders.

It is estimated that as many as 15% of married couples are affected by fertility disorders. The number of such couples seeking medical help has increased dramatically in the past 10 years due to both relative and absolute factors. The increase in population, the rising rate of sexually transmitted diseases, and the reduced availability of adoptable infants all contribute to the magnitude of this problem. The role of diagnostic imaging in the effective and compassionate care of couples desiring offspring is the subject of this review. Infertility is a disorder of a couple, not of two individuals. The diagnostic evaluation, therefore, must include both partners. Hysterosalpingography and ultrasound constitute the mainstay of the evaluation of the female member. The various techniques and complications of hysterosalpingography are reviewed. The normal appearance of the uterine cavity together with a review of the numerous anomalies and variations that might be encountered are presented. Along similar lines, the possible filling defects, synechiae, postoperative changes, and other alterations that may be encountered in imaging the uterine cavity are described. Evaluation of the fallopian tubes is of paramount importance, primarily to assess patency but also to assess the possibility of patent but diseased salpinges or disease of the surrounding peritubal tissue. Recently, interventional techniques using radiographic and sonographic control have been developed and are beginning to demonstrate promising results in the management of fallopian tube obstruction. These procedures, adapted from previously established radiographic interventive techniques, are discussed. The role of diagnostic imaging of the male partner is of lesser magnitude. Clinical assessment and semen evaluation generally permit adequate assessment of the male factor. Occasionally, however, vasography and seminal vesiculography are called into play. More frequently, sonographic evaluation to establish the presence of varicoceles is necessary. Such techniques are reviewed, as well as the interventional approaches for ablating varicoceles. The application of conventional and transvaginal sonography in the management of gynecologic fertility disorders is reviewed. Follicular monitoring, guided follicle aspiration, assessment of the status of the endometrium, guided embryo transfer and tubal cannulation, and evaluation of other pelvic disorders are significant factors in the appropriate management of the infertile couple.(ABSTRACT TRUNCATED AT 400 WORDS)

Risk factors associated with stress reactions in female Marines.

Women have a higher stress fracture rate than men in military studies, although the exact cause of this is not clear. Hyperpronation has been implicated as a potential risk factor for injury. In this prospective observational study, we measured subtalar joint range of motion in 101 women (ages 20-27 years) enrolled in Marine Corps Officer Candidate School in June 1994. The purpose of this study was to identify risk factors for injury in female Marine Corps officer candidates. The primary area of interest was the association between the amount of subtalar joint range of motion and stress reactions. Questionnaires were administered that explored previous physical activities, sports participation, and menstrual history. Anthropometric measurements were performed, including subtalar joint range of motion. During the 10 weeks of physical training, 11.5% of the women (N = 12) had stress reactions compared with 7% of the men (N = 10). There was no statistically significant difference in the means of subtalar joint range of motion in the stress reaction group compared with the non-stress reaction group. Differences in stress reaction rate across quartiles of subtalar joint range of motion were not significant. Those women who ran fewer miles (< or = 2.8 miles per session) before training had a higher rate of stress reactions (p < 0.04). Younger individuals (< 23 years) had a higher rate of stress reactions (p < 0.01). Women with fewer menstrual periods (< 10 per year) had a higher rate of stress reactions (p < 0.02). A narrow pelvis (< or = 26 cm) was associated with a higher rate of stress reactions (p < 0.09). We conclude that an increased subtalar joint range of motion is not a risk factor for stress reactions in women. However, further studies with a larger study population should be performed to confirm these findings.

Pneumoperitoneum secondary to pneumocolon examination.

A patient had pneumoperitoneum after an air contrast barium examination. We therefore reviewed perforations secondary to barium enema examinations and concluded that conservative management of this most unusual complication may be considered if there is no evidence of barium extravasation and if the clinical course is benign.

Angiomyolipomas in tuberous sclerosis: subselective embolotherapy with alcohol, with long-term follow-up study.

The use of subselective renal artery embolotherapy with absolute alcohol, using balloon occlusion to prevent backflow, is described in treating three hemorrhaging angiomyolipomas in two patients with tuberous sclerosis. Embolotherapy was chosen to treat the extensive hemorrhage and to spare the normal renal parenchyma. Literature reports of this treatment are reviewed, indicating it is one of the best methods for achieving a safe, permanent, and complete ablation.

Carcinoma of the fallopian tube.

Primary adenocarcinoma of the fallopian tube is a rare neoplasm that constitutes less than 1% of gynecologic malignancies. Although the triad of menorrhagia, leukorrhea, and pain is said to be pathognomonic, preoperative diagnosis of this lesion is most unusual. The radiographic appearance at hysterosalpingography has only rarely been described in the English literature previously. This therefore is an unusual documentation of the preoperative appearance of fallopian adenocarcinoma by hysterosalpingography and sonography.

Exploration of factors affecting mammography behaviors.

Of an estimated pool of 1,700 potential participants, only 382 (22%) eligible women participated in a low-cost breast cancer screening program offered to university and medical center employees. Because most women were still available and data were needed to understand why the opportunity to participate was refused by so many, a survey was done to determine factors related to mammography behavior. Three distinct groups of women were identified according to health beliefs, mammography behaviors, and modifying factors. Women who participated in the mammogram program were predominantly well-educated working women who were aware of mammography and its relationship to the breast cancer trajectory; they were affected by cost and convenience issues. One group of women did not participate in the program offered because they had had a recent mammogram; these women were at high risk for breast cancer and perceived mammography to be beneficial. The women who did not participate for other reasons were in nonprofessional jobs, had lower levels of education, and tended not to participate in the health care system as readily as women in the other groups; they perceived themselves less susceptible to breast cancer, valued mammography less, and knew less about breast cancer.

Written informed consent for i.v. contrast-enhanced radiography: patients' attitudes and common limitations.

In a multiinstitutional study, we surveyed 902 patients who were undergoing IV contrast-enhanced CT or IV urography; the purpose of the study was to determine patients' reactions to being given a written description of some of the risks associated with radiographic contrast material just before undergoing the examination. Ninety percent of the patients who responded said they would rather receive this information than not receive it. Ten percent said they preferred not to be given the information. Limitations in obtaining a truly informed consent were not rare and occurred in patients with medical emergencies (3% of cases) and in those with a limited understanding of risk disclosure (11% of cases). Patients in the latter category included those who were comatose or semicomatose (2%), those with dementia (1%), those with aphasia (0.8%), those who had psychiatric problems (0.8%), those who were sedated (0.6%), those who were unable to read (2%), those who were unable to understand English (2%), and those who perceived the information as too technical (0.9%). Two percent of the patients were minors. Our survey shows that practical limitations in obtaining adequate risk disclosure are common, but most patients want and accept information about the risks of having IV contrast-enhanced CT or IV urography before undergoing the procedure.

Certificate-of-need in an antitrust context.

Recent cases such as National Gerimedical Hospital and Gerontology Center v. Blue Cross of Kansas City have found that certificate-of-need (CON) legislation did not intend to remove antitrust considerations. This note discusses the exemptions from antitrust provided by the state action doctrine of Parker v. Brown as well as the Noerr-Pennington doctrine, both of which appear to protect provider input into the CON process. Providing information that assists decision-making must be carefully distinguished from providing data that serve the interests of physicians and hospitals.

Hexabrix as a contrast agent for hysterosalpingography.

Hexabrix, a monoacidic dimeric iodinated contrast material, was compared with Renografin 60 (diatrizoate meglumine) for safety, tolerance, and efficacy in hysterosalpingography, in a double blind study of 52 patients. No serious adverse reactions were noted in either group of patients. Discomfort during and after the procedure was not statistically different in the two groups. No difference in radiographic quality was seen. It was concluded that Hexabrix, despite reduced osmolality and increased viscosity, offers no significant benefit over Renografin 60, but it is a safe and acceptable contrast agent for hysterosalpingography.