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S Dowd

Publications and source records attributed to S Dowd.

At least 37 records · Page 2Linked to original sources
PubMed1996

The dynamics of rumours in the clinical setting.

In this article the social and psychological aspects of rumours are considered. The authors place rumours in a wider social context using definitions of different types of rumour before focusing on the nature of rumours in the healthcare environment. Some of the positive and negative consequences of rumours are examined and strategies which can help to minimise the spread of the misinformation characteristically contained in hospital rumours are highlighted.

Deception↗
PubMed1996

Differential regulation of the MAP, SAP and RK/p38 kinases by Pyst1, a novel cytosolic dual-specificity phosphatase.

The Pyst1 and Pyst2 mRNAs encode closely related proteins, which are novel members of a family of dual-specificity MAP kinase phosphatases typified by CL100/MKP-1. Pyst1 is expressed constitutively in human skin fibroblasts and, in contrast to other members of this family of enzymes, its mRNA is not inducible by either stress or mitogens. Furthermore, unlike the nuclear CL100 protein, Pyst1 is localized in the cytoplasm of transfected Cos-1 cells. Like CL100/ MKP-1, Pyst1 dephosphorylates and inactivates MAP kinase in vitro and in vivo. In addition, Pyst1 is able to form a physical complex with endogenous MAP kinase in Cos-1 cells. However, unlike CL100, Pyst1 displays very low activity towards the stress-activated protein kinases (SAPKs) or RK/p38 in vitro, indicating that these kinases are not physiological substrates for Pyst1. This specificity is underlined by the inability of Pyst1 to block either the stress-mediated activation of the JNK-1 SAP kinase or RK/p38 in vivo, or to inhibit nuclear signalling events mediated by the SAP kinases in response to UV radiation. Our results provide the first evidence that the members of the MAP kinase family of enzymes are differentially regulated by dual-specificity phosphatases and also indicate that the MAP kinases may be regulated by different members of this family of enzymes depending on their subcellular location.

3T3 Cells↗
PubMed1996

Proton magnetic resonance and human thyroid neoplasia III. Ex vivo chemical-shift microimaging.

Magnetic-resonance chemical-shift microimaging, with a spatial resolution of 40 x 40 microns, is a modality which can detect alterations to cellular chemistry and hence markers of pathological processes in human tissue ex vivo. This technique was used as a chemical microscope to assess follicular thyroid neoplasms, lesions which are unsatisfactorily investigated using standard histopathological techniques or water-based magnetic-resonance imaging. The chemical-shift images at the methyl frequency (0.9 ppm) identify chemical heterogeneity in follicular tumors which are histologically homogeneous. The observed changes to cellular chemistry, detectable in foci of approximately 100 cells or less, support the existence of a preinvasive state hitherto unidentified by current pathological techniques.

Adenocarcinoma, Follicular↗
PubMed1996

Two-dimensional proton magnetic resonance spectroscopy for tissue characterization of thyroid neoplasms.

We have previously demonstrated that one dimensional (1D) proton (1H) magnetic resonance spectroscopy (MRS) can distinguish normal thyroid tissue from thyroid carcinoma using a spectral ratio of peak intensity at 1.7 ppm/0.9 ppm. Two dimensional (2D) 1H-MRS allows identification of specific molecules that have overlapping peaks in the 1D-MR spectrum. Specimens from 93 consecutive thyroid nodules were examined using 2D 1H-MRS on a Bruker AM-360 wide-bore spectrometer. There was a progressive increase in lipid cross peaks assigned to di-/triglycerides when comparing colloid/hyperplastic nodules to follicular adenoma, and adenoma to carcinoma. A specific cross peak attributable to cholesterol/cholesteryl esters was commonly seen in carcinomas. In contrast, two unassigned cross peaks unique to the thyroid were more prevalent in benign lesions. There was an overall increase in cross peaks attributable to cell surface fucosylation in carcinoma when compared to benign lesions, although the fucose spectral pattern was not specific for cancer. On this basis, a spectral ratio of peak intensity at 2.05 ppm/0.9 ppm more clearly distinguished benign follicular adenoma from carcinoma. 2D 1H-MRS thus identifies chemical changes that allow more specific tissue characterization of thyroid neoplasms.

Adenoma↗
PubMed1995

Diagnosis of follicular thyroid lesions by proton magnetic resonance on fine needle biopsy.

Most thyroidectomies are currently performed for diagnostic purposes. It has been established that proton magnetic resonance spectroscopy (MRS) on excised thyroid tissue can distinguish normal thyroid from invasive carcinomas (P < 0.0001). The purpose of this study was to assess whether the same discrimination could be obtained preoperatively from fine needle biopsy (FNB). This has clinical importance because cytological examination of fine needle aspirates cannot distinguish between benign and malignant follicular thyroid lesions. Here we demonstrate a sensitivity of 95% for proton MRS to correctly identify clinically or histologically proven carcinoma. MRS measurements were made on FNB specimens (containing as few as 10(6) cells) from solitary thyroid nodules. MR assessment of FNB was inconsistent with that of the corresponding tissue in only 6.5% of cases. The discrimination between cancer and normal tissue was based on altered cellular chemistry measured as a one-dimensional spectral ratio of resonances from the amino acid lysine and lipid. Benign follicular lesions were separated into two groups: 67% with a spectral ratio similar to malignant thyroid tumors, and 33% with a spectral ratio comparable to that in normal thyroid tissue. Thus, in contrast with histopathology, MRS offers a method for assessment of FNB of follicular lesions with the potential to identify a biologically benign group, which could avoid thyroid surgery for purely diagnostic purposes.

Adenocarcinoma, Follicular↗
PubMed1994

Proton magnetic resonance and human thyroid neoplasia. I: Discrimination between benign and malignant neoplasms.

PURPOSE: Thyroid nodules are very common, yet the vast majority are biologically benign. The extreme difficulty facing the clinician selecting potentially malignant thyroid nodules for surgery was the subject of a recent editorial by Ernest L. Mazzaferri in the American Journal of Medicine (93:359-362, 1992). Here we evaluate the potential of proton magnetic resonance spectroscopy (1H MRS) to provide a solution to this problem. PATIENTS: Thyroid tissue from fifty-three patients undergoing partial or total thyroidectomy for solitary thyroid nodules were assessed by 1H MRS. RESULTS: When compared with the histologic diagnosis, 1H MRS distinguished normal thyroid tissue (n = 8) from invasive papillary (n = 9), anaplastic (n = 1), and medullary (n = 1) carcinomas with P values of < 0.0001, based on altered cellular chemistry. The same magnetic resonance (MR) criteria categorized pathologically proven follicular carcinoma (n = 8) (established as such by the presence of capsular or vascular invasion at the periphery of the tumor, or by the presence of metastases in the patient) with the other thyroid cancers (P < 0.0001). All other "benign" follicular neoplasms (n = 34), including five atypical follicular adenomas, were assessed by the same 1H MRS criteria and found to fit into one of the two above categories, viz. analogous to benign or malignant thyroid tissue. CONCLUSIONS: Proton MRS has the potential to separate out a group of truly benign follicular neoplasms from follicular tumors (both follicular adenomas and follicular carcinomas) that have an atypical follicular pattern on cytologic examination. This is the first report of an objective diagnostic procedure that has the potential to obviate surgical excision in a significant number of patients with benign follicular adenomas, independent of exhaustive histopathologic assessment.

Adenoma↗
PubMed1993

Magnetic resonance spectroscopy detects cancer in draining lymph nodes.

The spread of cancer cells to draining lymph nodes is an important prognostic factor for many cancers and influences postoperative therapy in patients. Histopathology is used routinely to assess if lymph nodes contain metastases. There are, however, time and resource constraints on the volume of lymph node tissue that can be examined by the pathologist in a routine laboratory (less than 2% of each node), thus major sampling errors are possible. Conventional histopathology also relies on identifying aggregates of malignant cells for a positive diagnosis. Proton (1H) magnetic resonance (MR) spectroscopy can detect chemical changes, specifically increased levels of lactate, choline, fucose and amino acids, in lymph nodes infiltrated by cancer. Increase in lactate indicates the presence of anaerobically respiring cells, whereas choline reports that the cells are replicating. Since MR spectroscopy can identify early infiltration by malignant cells, before cell clusters are visible under the light microscope, it detects micrometastases in lymph nodes missed histopathologically. Furthermore, MR spectroscopy eliminates sampling errors since the entire lymph node is examined.

Adenocarcinoma↗
PubMed1992

The evolving role of radiologic science professionals.

In summary, radiologic science professionals face a peculiar balancing act for the future. They must remain technologically able while practicing patient care that meets the expectations of a customer-oriented environment. That it will be difficult is without question--yet rising to meet challenges is one of the hallmarks of professionalism. Our own "new professionals" must stand ready to provide this leadership.

Forecasting↗
PubMed1991

Reporting child abuse.

This article reviews some representative state statutes in special reference to the responsibilities of the radiographer, in the hope to give radiographers and those in charge of departments of radiology a means to determine their liabilities according to their own state laws and institutional guidelines. It is not intended to serve as specific legal advice, but rather as a guide to radiographers and department managers.

Child↗
PubMedDate not supplied

Proton magnetic resonance and human thyroid neoplasia. II: Potential avoidance of surgery for benign follicular neoplasms.

Thyroid cancer is rare, but many thyroidectomies continue to be performed simply to exclude a diagnosis of malignancy. The purpose of this study was to determine the potential financial savings associated with the use of proton magnetic resonance analysis of follicular neoplasms. Proton magnetic resonance spectroscopy was performed on tissue obtained at the time of surgery from 98 consecutive solitary or dominant thyroid nodules. Fine-needle biopsies were also performed on operative specimens, and the tissues assessed by proton magnetic resonance; these spectra were then compared with those obtained from tissue specimens. An estimate of potential savings was obtained by comparing the magnetic resonance data with the indications for surgery and pathology on all patients having thyroidectomy over a 10-year period. Proton magnetic resonance spectroscopy was able to distinguish between normal thyroid tissue and invasive thyroid cancer with 100% specificity. Benign follicular adenomas fall into two groups: 44% having a spectral pattern comparable with normal thyroid, and the remaining 56% demonstrating an altered spectral pattern more comparable to the malignant magnetic resonance profile. Proton magnetic resonance spectroscopy on fine-needle biopsy specimens produced spectra similar to those from tissues from the same patient. From a fine-needle biopsy specimen, proton magnetic resonance spectroscopy can identify a group of benign follicular adenomas with spectral profiles akin to those of normal thyroid cells, thus avoiding the need for unnecessary surgical excision. The potential savings in one surgical unit alone were over $1 million in 10 years.

Adenocarcinoma, Follicular↗
PubMedDate not supplied

Euthanasia: a pragmatic view.

There will never be a simple resolution of the euthanasia debate, and perhaps there should not be. However, any policy in a pluralistic society should be based on the wishes of the individual so long as those wishes do not adversely affect others. Perhaps, as in the Netherlands, euthanasia needs to be decriminalised without being made legal, in a similar way to the decriminalisation of soft drugs such as marijuana (interestingly, the Dutch laws on drugs have also been held up as a possible standard for the USA as drug use in the Netherlands is much less problematic than in the USA (36). Individuals should be able to make difficult decisions regarding their own lives and healthcare workers should have the freedom, without fear of prosecution, to allow people in their care to pursue those options with dignity. This article has supported the proponent view of euthanasia--that it can be beneficial as it affirms individual autonomy. Compassionate carers must consider all the arguments in order to determine their own personal stand on the issue.

Attitude to Death↗
PubMedDate not supplied

Surgeon--assistant communication.

Although conflict is often viewed negatively, in reality, patient care can be enhanced by a combination of conflict and collaborative techniques. Strategic timing, along with an appropriate location for the interaction, is important in resolving a disagreement. A defensive approach will only cause an interaction to escalate--use a calm, objective approach instead.

Anger↗
PubMedDate not supplied

Managing a multicultural radiology staff.

Opportunities for minorities in healthcare increased with the Civil Rights movement in the 1960s. More recently, funds from the U.S. Public Health Service have been targeted toward disadvantaged minorities. The workforce in healthcare, and in business in general, has become increasingly multicultural. Much of the literature in healthcare management lacks practical guidelines for managing a diverse workforce. Communication, both verbal and nonverbal, and culture are closely intertwined. Managers, as they develop multicultural teams, will need to understand how culture influences communication in their organizations. Space, spatial behavior, and cultural attitudes influence people's behavior. This is a particularly important consideration for a radiology staff, which must often work in close quarters. For some cultural groups, the family as an organization has more significance than even personal, work-related or national causes. People's orientation to time, whether for the past, present or future, is usually related to the culture in which they grew up. Again, this may become an important issue for a radiology administrator whose organization must run punctually and time-efficiently. How patients feel about their environment, whether they believe they are in control or believe in an external locus of control, is of particular interest to those who attempt therapeutic changes in a patient's healthcare. Does the patient believe that illness is divine will or that suffering is intrinsic to the human condition? There is increasing research in the United States to show that people do differ biologically according to race. Such differences exist among patients as well as among staff members. It has been popular to assume that differences among races do not exist. Unfortunately such an attitude does not allow for different attributes and responses of individuals. Managing a multicultural staff presents a challenge to administrators who must be skilled in working with culturally diverse people and must help their staff members do the same.

Cultural Diversity↗
PubMedDate not supplied

Should technologists tell everything they know?

Students and staff technologists used to be taught to give no information to patients, an easy stance but hardly justifiable. Today's technologists are professional practicing in advanced settings; today's patients want and often demand information. How do we ensure that the pendulum of providing healthcare information does not swing from telling patients nothing to telling patients everything? Only recently have patient-care texts begun to recognize this as a dilemma, with the unanswered question remaining: how much do we tell them when they ask? The desire to look like an expert may lead technologists, particularly those who are newly graduated and enthusiastic, into providing information to a patient before evaluating its appropriateness. Technologists working with anxious or worried patients may also give out information to ease both their own and the patient's feelings of anxiety. Many patients are really looking for reasonable reassurance about their tests and illness, not detailed information. There are three types of technologists: the revealer, the hider and the expert. The latter has learned to evaluate information for its appropriateness for patients to hear and their ability to receive it. As part of the ongoing learning process, technologists need to consider how to evaluate a patient's motive for asking a question, to decide the answer's effect on the patient, determining who is the most appropriate person to answer the question, and finally, judging how much information is best for the patient to hear. For the most apprehensive patient, distraction may be a useful technique.

Anxiety↗
PubMedDate not supplied

Opening up to the Katz Index.

As assessment of functional ability becomes more and more important to nurses as well as other members of the interdisciplinary team, the Katz index is a useful instrument to have available. The Katz Index is a simple instrument. This is both a strength and a deficit. The IADLs are not evaluated with the index. It has some deficits that make it less useful in rehabilitation and of more value in nursing and interdisciplinary research. In any case, it is a useful tool with which nurses should be familiar when seeking a way to measure functional ability of older adults EC.

Activities of Daily Living↗