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Biomedical subjects

K A Hall

Publications and source records attributed to K A Hall.

At least 19 recordsLinked to original sources
PubMed2000

The status of Petalocotyle Ozaki, 1934 (Digenea: Gyliauchenidae), including the description of two new species from acanthurid fishes in Queensland, Australia.

The status of Petalocotyle Ozaki, 1934 within the Gyliauchenidae Goto & Matsudaira, 1918 is reviewed. Two new species, P. adenometra from Prionurus microlepidotus (Amity Point, Queensland, Australia) and P. diverticulata from Acanthurus nigrofiuscus and A. lineatus (Heron Island, Queensland, Australia), are described. The body plan of Petalocotyle conforms to that of members of the Gyliauchenidae (oral sucker absent, well-developed pharynx, complex oesophagus and characteristic male terminal genitalia), indicating justifiable inclusion in this family. A new diagnosis is given for the genus, such that Petalocotyle is now identified by the presence of an anterior, protuberant ventral sucker, long caeca, a large, sigmoid cirrus-sac containing a coiled ejaculatory duct, and an extensive vitellarium. We suggest that, of all the known genera of gyliauchenids, Petalocotyle may most closely resemble the 'archaetypal gyliauchenid', that is, it may be placed basally within the radiation of the Gyliauchenidae. However, derived characters, like diverticula in the reproductive system, indicate that some characters of individual members of Petalocotyle may be considered advanced and do not reflect an archaetypal condition. Parallels in the structure of the male and female genitalia of Robphildollfusium Paggi & Orecchia, 1963 and Petalocotyle, along with the shared morphology of the digestive tract, indicate possible phylogenetic links between the two genera. This affinity is difficult to infer using morphology alone and recommend that Robphildollfusium remain detached from the Gyliauchenidae.

Animals↗
PubMed1999

Consistency of handwriting movements in dementia of the Alzheimer's type: a comparison with Huntington's and Parkinson's diseases.

Patients with dementia of the Alzheimer's type (DAT) and their matched controls wrote, on a computer graphics tablet, 4 consecutive, cursive letter 'l's, with varying levels of visual feedback: noninking pen and blank paper so that only the hand movements could be seen, noninking pen and lined paper to constrain their writing, goggles to occlude the lower visual field and eliminate all relevant visual feedback, and inking pen with full vision. The kinematic measures of stroke length, duration, and peak velocity were expressed in terms of consistency via a signal-to-noise ratio (M value of each parameter divided by its SD). Irrespective of medication or severity, DAT patients had writing strokes of significantly less consistent lengths than controls', and were disproportionately impaired by reduced visual feedback. Again irrespective of medication or severity, patients' strokes were of significantly less consistent duration, and significantly less consistent peak velocity than controls', independent of feedback conditions. Patients, unlike controls, frequently perseverated, producing more than 4 'l's, or multiple sets of responses, which was not differentially affected by level of visual feedback. The more variable performance of patients supports a degradation of the base motor program, and resembles that of Huntington's rather than Parkinson's disease patients. It may indeed reflect frontal rather than basal ganglia dysfunction.

Aged↗
PubMed1999

V4 region of small subunit rDNA indicates polyphyly of the Fellodistomidae (Digenea) which is supported by morphology and life-cycle data.

There is no morphological synapomorphy for the disparate digeneans, the Fellodistomidae Nicoll, 1909. Although all known life-cycles of the group include bivalves as first intermediate hosts, there is no convincing morphological synapomorphy that can be used to unite the group. Sequences from the V4 region of small subunit (18S) rRNA genes were used to infer phylogenetic relationships among 13 species of Fellodistomidae from four subfamilies and eight species from seven other digenean families: Bivesiculidae; Brachylaimidae; Bucephalidae; Gorgoderidae; Gymnophallidae; Opecoelidae; and Zoogonidae. Outgroup comparison was made initially with an aspidogastrean. Various species from the other digenean families were used as outgroups in subsequent analyses. Three methods of analysis indicated polyphyly of the Fellodistomidae and at least two independent radiations of the subfamilies, such that they were more closely associated with other digeneans than to each other. The Tandanicolinae was monophyletic (100% bootstrap support) and was weakly associated with the Gymnophallidae (< 50-55% bootstrap support). Monophyly of the Baccigerinae was supported with 78-87% bootstrap support, and monophyly of the Zoogonidae + Baccigerinae received 77-86% support. The remaining fellodistomid species, Fellodistomum fellis, F. agnotum and Coomera brayi (Fellodistominae) plus Proctoeces maculatus and Complexobursa sp. (Proctoecinae), formed a separate clade with 74-92% bootstrap support. On the basis of molecular, morphological and life-cycle evidence, the subfamilies Baccigerinae and Tandanicolinae are removed from the Fellodistomidae and promoted to familial status. The Baccigerinae is promoted under the senior synonym Faustulidae Poche, 1926, and the Echinobrevicecinae Dronen, Blend & McEachran, 1994 is synonymised with the Faustulidae. Consequently, species that were formerly in the Fellodistomidae are now distributed in three families: Felldistomidae; Faustulidae (syn. Baccigerinae Yamaguti, 1954); and Tandanicolidae Johnston, 1927. We infer that the use of bivalves as intermediate hosts by this broad range of families indicates multiple host-switching events within the radiation of the Digenea.

Animals↗
PubMed1998

Open surgical biopsy for nonpalpable mammographic abnormalities: still an option compared with core needle biopsy.

OBJECTIVE: Our purpose was to present information about open surgical biopsy. It is hoped that this will be helpful when reviewing information about core needle biopsy STUDY DESIGN: Review of 461 open surgical biopsies for nonpalpable mammographic abnormalities was performed. All patients were managed by the Women's Health Center of Logansport. Core needle biopsy data came from the literature. RESULTS: Open surgical biopsy compared favorably to core needle biopsy with regard to accuracy, cost, patient convenience, recovery, adequacy of specimen, identification of primary site, and cosmetics. CONCLUSION: Despite core needle biopsy marketing, open surgical biopsy has its advantages and should not be relegated to the museum.

Biopsy↗
PubMed1997

Response programming in dementia of the Alzheimer type: a kinematic analysis.

Although planning is important for the functioning of patients with dementia of the Alzheimer Type (DAT), little is known about response programming in DAT. This study used a cueing paradigm coupled with quantitative kinematic analysis to document the preparation and execution of movements made by a group of 12 DAT patients and their age and sex matched controls. Participants connected a series of targets placed upon a WACOM SD420 graphics tablet, in response to the pattern of illumination of a set of light emitting diodes (LEDs). In one condition, participants could programme the upcoming movement, whilst in another they were forced to reprogramme this movement on-line (i.e. they were not provided with advance information about the location of the upcoming target). DAT patients were found to have programming deficits, taking longer to initiate movements, particularly in the absence of cues. While problems spontaneously programming a movement might cause a greater reliance upon on-line guidance, when both groups were required to guide the movement on-line, DAT patients continued to show slower and less efficient movements implying declining sensori-motor function; these differences were not simply due to strategy or medication status.

Aged↗
PubMed1996

Vitamin E levels in human atherosclerotic plaque: the influence of risk factors.

Recent studies suggest that vitamin E may be an important preventative factor in the development and progression of atherosclerosis. In order to more clearly define the role of vitamin E in atherosclerosis, we measured vitamin E, conjugated diens, and lipid flurochromes, as well as cholesterol, triglycerides and phospholipid in arterial and venous tissue of 83 patients. Serum cholesterol and triglyceride levels were significantly higher (P < 0.05) in patients with aortic occlusive (AIOD) and aneurysmal (AAA) disease than in control organ donors (OD). Tissue cholesterol concentrations were significantly elevated in AAA tissue when compared to OD and tissue from patients with peripheral occlusive disease (POD). Tissue from patients with AIOD contained greater concentrations of phospholipid (PL) than were measured in patients with POD and in OD. Vitamin E concentrations were highest in POD tissue and approximately 3.0, 2.0, and 1.6 fold greater than OD, AIOD and AAA tissue respectively. Diene conjugates and lipid flurochromes, measures of early and intermediate products of lipid peroxidation, were markedly elevated in all diseased arterial tissue compared to controls. There were no significant differences in tissue or serum lipid levels between saphenous vein (SVBG) and diseased vein grafts (DVG). However, conjugated diene concentrations were elevated in DVG compared to SVBG. Vitamin E levels were significantly elevated in diseased arterial and venous tissue (AIOD, AAA, POD, DVG) removed from patients with diabetes (P = 0.013) and hypertension (P = 0.049) compared to those without these risk factors. Diabetes was the only risk factor associated with significantly increased (P = 0.005) levels of vitamin E when only data from atherosclerotic arterial tissue (AAA, POD, AIOD) were analyzed. These preliminary data provide additional evidence of altered vitamin E metabolism and free radical processes in the tissues of patients with various manifestations of atherosclerosis.

Adolescent↗
PubMed1996

Incidence and histologic characteristics of blebs in patients with abdominal aortic aneurysms.

PURPOSE: Aortic blebs-focal outpouchings within aortic aneurysms-may contribute to their eventual rupture. In this study we determine the incidence of aortic blebs and describe their microscopic features. METHODS: Computed tomographic scans of the abdominal aorta were obtained in 188 patients with aortic diameters measuring > or = 3 cm and were independently evaluated by a radiologist. The number and location of blebs were recorded, and each was measured with calipers. Sixteen blebs, with an adjacent uninvolved aneurysmal segment of aorta, and tissue from two patients with ruptured aneurysms were examined by light microscopy and immunohistochemical analysis. Specimens from six blebs and five aneurysms were examined for alpha 1 (I) procollagen messenger RNA by in situ hybridization. RESULTS: Twenty blebs, ranging in size from 5 to 30 mm (mean, 12 +/- 7 mm), were detected in 11% (20 of 188) of computed tomographic scans. Blebs were observed in 10% (11 of 111) of patients with aortic diameters between 3.0 and 4.9 cm, 10% (6 of 61) of patients with aneurysms between 5.0 and 6.9 cm, and 19% (3 of 16) of patients with aortic diameters > or = 7 cm. Histologically, the major difference between the aneurysmal aortic wall and blebs was found in the media. In aneurysmal aortas, the media consisted of multiple layers of fragmented elastic lamellae, whereas the number of elastic tissue elements along the circumference of the blebs progressively decreased; only a few isolated fragments of elastic tissue were present at the apices. Histologic evidence of rupture was evident in two specimens. A chronic inflammatory cell infiltrate composed of T and B lymphocytes, plasma cells, and macrophages, common to both the aneurysmal and the blebs, was most prominent in the adventitia of aneurysmal tissue, but involved both the media and adventitia of the blebs. In situ hybridization demonstrated the presence of alpha 1 (I) procollagen messenger RNA in four of the five aneurysm segments that were evaluated, compared with only one of six blebs. CONCLUSIONS: Blebs were discovered in aneurysms of all sizes; their frequency appeared to be unrelated to aneurysm size. The presence of inflammatory cell infiltrates and absence of alpha 1 (I) procollagen messenger RNA in five of six blebs suggest that a local imbalance of matrix degradation and repair plays a role in the cause of these lesions. Attenuation of the aortic wall accompanying the formation of blebs may predispose these sites to rupture.

Aorta, Abdominal↗
PubMed1995

Abdominal wall hernias in patients with abdominal aortic aneurysmal versus aortoiliac occlusive disease.

BACKGROUND: This study was undertaken to determine the incidence of ventral incisional hernias (VIHs) and inguinal hernias (IHs) in patients with abdominal aortic aneurysmal (AAA) versus those with aortoiliac occlusive disease (AIOD). PATIENTS AND METHODS: The medical records of 193 patients (128 with AAA and 65 with AIOD) who had undergone elective aortic reconstruction were reviewed to determine the number and location of abdominal wall hernias (AWHs). RESULTS: Forty-one AWHs (28 IHs and 13 VIHs) were detected in patients with AAA compared to 13 (11 IHs and 2 VIHs) in patients with AIOD. There was a significantly greater incidence of VIHs in patients with AAA versus patients with AIOD (10% versus 3%, P < 0.05) and recurrent AWHs (28% versus 19%, P < 0.01), but not of IHs (22% versus 17%). CONCLUSION: Patients with AAA have a higher incidence of VIHs and recurrent AWHs--without a corresponding increase in patient-related risk factors--than patients without aneurysm, suggesting that as yet unidentified etiologic factors may contribute to the development of AWHs in these patients.

Aorta, Abdominal↗
PubMed1995

Prospective evaluation of peripheral vascular disease in heart transplant recipients.

PURPOSE: Retrospective reviews suggest that the progression of peripheral vascular disease (PVD) may be accelerated in heart transplant recipients. This study was undertaken to determine the incidence and to identify those risk factors that may be associated with the development or progression of PVD in these patients. METHODS: Between January 1990 and December 1993 a prospective vascular screening protocol including abdominal ultrasonography, Doppler-derived ankel-brachial pressure indexes (ABI), and carotid artery duplex imaging was added to the routine preoperative and annual postoperative evaluation of 239 heart transplant recipients. RESULTS: Thirty-one significant vascular lesions were detected in 10% (24 of 239) of patients 52 +/- 9 years of age at a mean of 3.2 years after transplant. The distribution of lesions included carotid artery stenosis (11), femoropopliteal occlusive disease (10), aortoiliac occlusive disease (five), aortic aneurysm (four), and renal artery stenosis in one patient. Revascularization procedures were performed in 12 (50%) patients (carotid endarterectomy (four), aortobifemoral bypass grafting (three), abdominal aortic aneurysm repair (two), transluminal angioplasty (two), splenorenal bypass (one), and femorotibial bypass grafting (one)). One patient with diabetes mellitus (DM) was found to have noncompressible vessels during pretransplant evaluation. An additional 26 patients (11%), seven with DM, had noncompressible vessels in the lower extremities during the follow-up period. Logistic regression analysis revealed that the development of posttransplant PVD was associated with smoking (p < 0.05) and ischemic cardiomyopathy as an indication for transplantation (p < 0.05). The development of noncompressible vessels was associated with younger age (p < 0.05) and the presence of diabetes (p < 0.05). CONCLUSION: Posttransplant peripheral vascular disease occurred in 10% of heart transplant recipients and is associated with pretransplant ischemic cardiomyopathy and smoking. A previously unrecognized subgroup of patients who have noncompressible vessels after operation is described. If the long-term survival of the heart transplant recipient is to be improved, routine follow-up to identify and treat those patients at greater risk appears justified.

Adolescent↗
PubMed1994

Thoracoscopic excision of a peripheral corticotropin-secreting pulmonary carcinoid tumor.

Bronchial carcinoid tumors are rare neuroendocrine neoplasms that arise from the Kulchitsky cells of the bronchial epithelium. These tumors can manifest as central carcinoid tumors, pulmonary carcinoid tumorlets, or peripheral carcinoid tumors. Occasionally, the peripheral carcinoid tumors produce corticotropin and result in Cushing's syndrome. Herein we report the first case of Cushing's syndrome associated with a peripheral pulmonary carcinoid tumor that was excised by video-assisted thoracoscopy. After excision, the patient had complete remission. Video-assisted thoracoscopy may be ideal for resecting a peripheral pulmonary carcinoid, especially in patients with debilitation but no evidence of metastasis.

Adrenocorticotropic Hormone↗
PubMed1993

Mammographic abnormalities and the detection of carcinoma of the breast.

OBJECTIVE: In an attempt to reduce the number of unnecessary breast biopsies, the yield rate of cancer relative to specific types of mammographically detected abnormality was investigated. STUDY DESIGN: Between 1989 and 1991, 169 patients with an abnormality as detected by mammogram but with no palpable mass were reviewed. Abnormalities detected by mammogram were divided into four types. The rate of biopsy-confirmed cancer per type of abnormality was calculated. RESULTS: The incidence of cancer per type of mammographically detected abnormality was as follows: mass 11%, mass with abnormal calcification 21%, abnormal calcification 22%, and asymmetric density 2%. CONCLUSION: Biopsy is recommended for mammographically detected abnormalities of a mass, a mass with abnormal calcification, and abnormal calcification without mass. Consideration should be given to deferring biopsy in favor of a follow-up study for asymmetric densities.

Biopsy↗
PubMed1992

Contrast-induced nephrotoxicity: the effects of vasodilator therapy.

The increasingly frequent use of contrast-enhanced imaging for diagnosis or intervention in patients with peripheral vascular disease has generated concern about the incidence and avoidance of contrast-induced nephrotoxicity (CIN). In this prospective study, we sought to identify those patients at greater risk of developing CIN and to evaluate the efficacy of vasodilator therapy with dopamine in limiting this complication. Baseline serum creatinine (Cr) concentrations were obtained on admission and daily for up to 72 hr after angiography in 222 patients undergoing 232 angiographic procedures. The preangiographic treatment was varied at 2-month intervals for 1 year. All patients received an intravenous infusion of 5% dextrose and 0.45% normal saline at a rate of 75 to 125 ml/hr. During the first interval patients received 12.5 g of 25% mannitol immediately prior to their contrast load, in addition to intravenous fluids. During the next 2-month period the patients were given renal dose dopamine intravenously (3 micrograms/kg/min) commencing the evening before angiography and continued to the next morning. During the latter half of the study the treatment regimens were modified so that the use of mannitol was restricted to patients with diabetes mellitus and dopamine to patients with serum creatinine concentrations of > or = 2 mg/dl. Postangiographic elevation in Cr occurred in 2, 10.4, and 62% of studies in patients with baseline creatinine levels of < or = 1.2 mg/dl, 1.3 to 1.9 mg/dl, and > or = 2.0 mg/dl, respectively. None of the patients receiving dopamine experienced an elevation in creatinine. There was no statistical correlation between age, diabetes, or medication with calcium channel blockers and CIN.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Surgical management of breast disease in an obstetrics and gynecology group.

The surgical management of breast disease from 1978 through 1988 by the Women's Health Center of Logansport is reviewed. Three hundred twelve biopsy procedures resulted in the diagnosis of 59 cancers. Biopsy and mastectomy procedures were performed by the authors (obstetrician-gynecologists). There were no significant complications and all patients had an adequate surgical result. Preoperative needle localization techniques proved to be a safe and effective method to identify and remove nonpalpable mammographic abnormalities. Because women depend on their gynecologist for advice regarding reproductive organs including the breasts, it is logical for the gynecologic surgeon to become involved in the surgical management of breast disease.

Adult↗
PubMed1988

Aortic valve selection in the elderly patient.

To determine the influence of valve selection on valve-related morbidity and mortality and patient survival, comparative long-term performance characteristics of mechanical (N = 68) and bioprosthetic (N = 73) heart valves were analyzed for 141 patients more than 70 years old who underwent isolated aortic valve replacement between 1970 and 1985. Cumulative patient follow-up was 491 patient-years (average, 4.3 years per patient). Hospital mortality was 18% and 19% for patients with mechanical valves and bioprosthetic valves, respectively. Survival at 5 years was 61 +/- 7% (+/- the standard error) and 67 +/- 10% for recipients of mechanical valves and bioprosthetic valves, respectively. Male sex (p = 0.014) and urgency of operation (p = 0.006) were independent risk factors for hospital mortality. Atrial fibrillation increased valve-related mortality (p = 0.01). No patient required reoperation or experienced structural valve failure. While anticoagulant-related hemorrhage was increased in recipients of mechanical valves (9.2 +/- 2.1%/patient-year) compared with recipients of bioprosthetic valves (2.3 +/- 1.1%/patient-year), it did not result in a death or lead to permanent disability. There was no difference in freedom from any valve-related complication at 5 years. However, when all morbid events are considered, recipients of bioprosthetic valves experienced fewer valve-related complications than patients receiving mechanical valves (10.7 +/- 2.3%/patient-year versus 17.6 +/- 2.5%/patient-year, respectively; p less than 0.05). The reduced incidence of anticoagulant-related hemorrhage and the infrequent need for warfarin sodium anticoagulation favor selection of a bioprosthetic heart valve in patients older than 70 years.

Aged↗