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S McCarthy

Publications and source records attributed to S McCarthy.

At least 19 recordsLinked to original sources
PubMed1999

Further investigations on the hydrolytic degradation of poly (DL-lactide).

The hydrolytic degradation of poly(DL-lactide) (PLA50) material was investigated in order to elucidate the effects of temperature and acidity of the external medium on the degradation characteristics. It was observed that at 60 degrees C and at pH = 7.4, degradation was extremely rapid as compared with degradation at 37 degrees C. After only 2 days, heterogeneous degradation was observed due to larger internal autocatalysis. On the other hand, in the case of degradation at 37 degrees C in an acidic medium with pH = 3.7, the heterogeneous degradation was preceded by a much longer lag time. Water absorption was found to be pH dependent. At pH = 7.4, water absorption was increased due to the osmotic pressure driving the buffer solution into the polymer matrix to neutralize acidic endgroups, which was not the case for degradation at pH = 3.7. In both cases, the oligomeric stereocomplex was obtained as degradation residue at the end of the degradation period.

Biocompatible Materials↗
PubMed1999

Total-body echo-planar MR imaging in the staging of breast cancer: comparison with conventional methods--early experience.

PURPOSE: To test breast cancer staging with total-body echo-planar magnetic resonance (MR) imaging. MATERIALS AND METHODS: Nineteen patients with newly diagnosed breast cancer were imaged by using a 1.5-T echo-planar MR system. By using a table sweep method, 180 contiguous axial images were obtained from the cranial vertex through the feet with T2-weighted spin-echo and inversion-recovery sequences. Results were compared with those of conventional imaging. Therapeutic decisions based on echo-planar MR imaging and conventional imaging results were compared. Diagnostic truth was determined by means of tissue diagnosis, further imaging findings, and follow-up findings (median, 18 months). RESULTS: Staging with total-body echo-planar MR imaging was correct in 18 patients (95%)--eight with metastases and 10 without--while staging with conventional imaging was correct in 15 patients (79%). In one patient, both echo-planar MR imaging and conventional imaging findings incorrectly indicated probable metastases. In one patient thought to have bone metastases at conventional imaging, echo-planar MR imaging findings were normal, which was correct. Two patients with stage IV disease were not suspected to have disease at conventional imaging: One had liver involvement and the other had skeletal metastases. The therapeutic decisions in these two patients were altered by the echo-planar MR imaging results. CONCLUSION: Total-body echo-planar MR imaging was at least as accurate as conventional imaging for staging newly diagnosed breast cancer and was faster, simpler, and completely noninvasive.

Adult↗
PubMed1998

Intrusive memories and depression in cancer patients.

Matched samples of depressed and nondepressed cancer patients were interviewed about past life events, particularly experiences of death and illness. They identified and described any spontaneous intrusive visual memories they had experienced in the past week corresponding to these events. About one quarter reported such memories and, as predicted, the majority of intrusive memories concerned illness, injury and death. The mean levels of intrusion and avoidance were equivalent to patients with post-traumatic stress disorder. Consistent with prediction, depressed patients reported significantly more intrusive memories than controls, and described the memories as typically beginning with or being exacerbated by the onset of depression. Greater numbers of intrusive memories were associated with more maladaptive coping, and greater avoidance with deficits in autobiographical memory functioning.

Adaptation, Psychological↗
PubMed1998

Does pelvic magnetic resonance imaging differentiate among the histologic subtypes of uterine leiomyomata?

OBJECTIVE: To evaluate if pelvic magnetic resonance imaging (MRI) is reliable for differentiating leiomyoma subtypes. DESIGN: Prospective study. SETTING: Academic center. PATIENT(S): Forty-five patients underwent MRI before surgery for leiomyomata. INTERVENTION(S): One radiologist blinded to patient history and histologic diagnosis recorded the MRI characteristics and classification of the largest leiomyoma. MAIN OUTCOME MEASURE(S): Comparison of MRI and histologic diagnoses. RESULT(S): Leiomyoma subtypes were diagnosed accurately by MRI in 69% of cases. Magnetic resonance imaging had a 95% sensitivity and 72% specificity for diagnosing an uncomplicated leiomyoma and a 10% sensitivity and 100% specificity for a cellular leiomyoma. For cystic leiomyomata, the sensitivity was 80% and specificity was 98%, and for hemorrhagic leiomyomata, 100% and 86%, respectively. Magnetic resonance imaging correctly diagnosed all malignant tumors and did not incorrectly diagnose a leiomyoma as a leiomyosarcoma in any case. Ill-defined MRI margins were significantly more likely to be leiomyosarcoma, whereas well-defined margins were characteristic of benign lesions. Hemorrhagic leiomyomata were significantly more likely to be hyperintense on T1-weighted images than other subtypes. CONCLUSION(S): Although MRI is only fairly accurate in differentiating the subtypes of benign uterine smooth muscle tumors, signal intensities and margin characteristics are useful to distinguish accurately benign from malignant tumors.

Adult↗
PubMed1998

Spitz nevus versus spitzoid malignant melanoma: an evaluation of the current distinguishing histopathologic criteria.

Because of the well-known difficulty in distinguishing between Spitz nevi and spitzoid malignant melanomas at the microscopic level, the critical importance of this task notwithstanding, expert dermatopathologists across the world have strenuously endeavored to identify histopathologic criteria that would assist microscopists in this effort. Many reports itemizing such criteria are extant. The objective of the current study was to determine which of these criteria serve as the most consistent discriminators. Using a population of 11 spitzoid melanomas and 12 Spitz nevi, we evaluated six sets of criteria purported to be helpful in differentiating between these entities. Overall, we found that six features had significant distinguishing capacity, namely, (1) Kamino bodies, (2) a brisk mitotic rate, (3) mitoses close to the base of the lesion, (4) abnormal mitoses, (5) symmetry, and (6) uniformity of nests from side to side. It is noteworthy that the first three of these rank among the six criteria itemized repeatedly in 50% or more of the sets of criteria evaluated.

Adolescent↗
PubMed1998

Memory processes and the course of anxiety and depression in cancer patients.

BACKGROUND: Intrusive memories of stressful events, many involving illness and death, are found in a minority of depressed cancer patients, and may predict the course of anxiety and depression. METHOD: Matched samples of mild to moderately depressed and non-depressed cancer patients were followed up after 6 months. Anxiety and depression at follow-up were related to measures of intrusive memories of stressful life events and autobiographical memory functioning that had been assessed at baseline. RESULTS: Levels of anxiety and depression remained fairly constant over time in the two groups, and the depressed group continued to experience high levels of intrusive memories. The presence of intrusive memories at baseline, and the extent to which these memories were consciously avoided, predicted greater anxiety at follow-up, even after controlling for initial severity of physical and psychiatric symptoms. None of the measures of memory functioning predicted levels of depression at follow-up. CONCLUSIONS: Intrusive memories appear to be a marker of more prolonged psychopathology in cancer patients and may respond to direct therapeutic intervention.

Adult↗
PubMed1998

A phase I and pharmacokinetic study of LY231514, the multitargeted antifolate.

LY231514 is a novel antifolate that principally inhibits thymidylate synthase, but with additional folate-dependent enzyme targets. A Phase I study of single-agent LY231514 administered as a daily i.v. infusion over 10 minutes for 5 days, repeated every 3 weeks, was conducted to evaluate the maximum tolerated dose, pharmacokinetic profile, and antitumor activity of the drug using this schedule. Thirty-eight patients with advanced malignancies that were refractory or not amenable to standard therapy were treated with a total of 116 courses of LY231514, escalating treatment doses through 10 dose levels, from 0.2-5.2 mg/m2/day. No objective clinical responses were observed, although minor antitumor activity not fulfilling the response criteria was seen in three patients. A maximum tolerated dose of 4.0 mg/m2/day was determined, with neutropenia as the predominant dose-limiting toxicity. Reversible disturbances of liver biochemistry, fulfilling the protocol definitions of dose-limiting toxicity, were also observed. Other toxicities included diarrhea, mucositis, skin rash, and fatigue. Pharmacokinetic studies were performed at all treatment levels. Analysis showed a linear relation between administered dose and both maximum plasma concentration (Cmax) and area under the plasma concentration/time curve. The drug was cleared with a day 1 total body clearance of 108.9 +/- 38.8 ml/min/m2, with plasma concentrations declining with a mean harmonic terminal half-life of 1.4 +/- 0.98 h. When given by this schedule, LY231514 is tolerable, and Phase II studies are in progress.

Adult↗
PubMed1997

Do triage nurse-initiated X-rays for limb injuries reduce patient transit time?

Patients with isolated limb injuries are often required to wait a long time for treatment and investigation in emergency departments. It was hypothesized that allowing triage nurses to initiate X-rays would reduce transit times for these patients. A prospective, randomized comparison trial of 175 patients was conducted, comparing transit times between a group of patients who had X-rays initiated at triage and a group which did not. No statistically significant reduction in transit time was demonstrated by this change in practice, either for a group who had sustained fractures or for one which had not. Despite this finding, staff and patient satisfaction with this change in procedure was high. This justifies continuation of the practice and further research.

Adolescent↗
PubMed1997

Fibroma and fibrothecoma of the ovary: MR imaging findings.

PURPOSE: To describe the morphologic and signal intensity characteristics on magnetic resonance (MR) images of fibromas and fibrothecomas. MATERIALS AND METHODS: MR images of 11 female patients with histologically proved fibromas or fibrothecomas were reviewed, and morphologic and signal intensity characteristics of the lesions were analyzed. MR imaging findings were correlated with histologic findings. RESULTS: All fibromas and fibrothecomas showed homogeneous low signal intensity on T1-weighted images. On T2-weighted images, the two smallest lesions showed homogeneous low signal intensity, and eight of the other nine lesions showed predominantly low signal intensity. Edema was noted only in larger lesions, and cystic degeneration was noted only in three of the largest lesions. On T2-weighted images, the percentage of low signal intensity in the lesion was not found to be related to lesion size, and the percentage of low signal intensity in fibromas was not significantly different from that in fibrothecomas (P = .55). Many lesions showed heterogeneous signal intensity; the solid component was distributed peripherally, and the cystic component was located centrally or eccentrically. Free intraperitoneal fluid was noted in 10 of 11 lesions and was not significantly correlated with lesion size (r = .52 and P = .10). CONCLUSION: Because of their predominantly low signal intensity on T2-weighted images, fibromas and fibrothecomas display a relatively specific appearance on MR images.

Adolescent↗
PubMed1997

Autosomal dominant polycystic kidney disease: pathophysiology and treatment.

Once viewed as a hopelessly incurable disease, autosomal dominant polycystic kidney disease (ADPKD) has been given a great deal of attention as geneticists search for ADPKD genes, and cell biologists are studying and understanding cyst formation. Alterations in cellular growth, secretion, and extracellular matrix all participate in cystogenesis. ADPKD is one of the most common hereditary diseases in the United States and is a frequent cause of chronic renal failure. The disease is a systemic disorder that may affect multiple organ systems. Manifestations of ADPKD in renal and extrarenal systems may be challenging problems in the management of these patients. Although no therapy is available, treatment of the complications is highly effective in most cases in supportive management of the disease.

Humans↗
PubMed1996

Hemolytic reactions mechanically induced by kinked hemodialysis lines.

Ten hemolytic reactions occurred in our outpatient hemodialysis unit over a 12-month period (December 1989 to December 1990). Eight patients were hospitalized and one died. All patients developed severe abdominal or back pain an average of 2.5 hours into a 4-hour hemodialysis session using a bleach/formaldehyde reprocessed hollow-fiber cupraphan dialyzer (average reuse, three times) with blood flow rates of 375 mL/min. All had visible hemolysis in a spun hematocrit, seven had a significant decrease in hematocrit, and six developed pancreatitis. Hemolysis was further confirmed by a decrease in haptoglobin in all patients and an increase in lactic dehydrogenase in all but the last case. Investigation of each episode failed to find an abnormality in dialysate temperature or tonicity; dialysate or water levels of copper, zinc, nitrates, chloramine, or formaldehyde; or blood pump or venous alarm. Hemolytic reactions continued despite changing to 15-gauge needles, removing bleach from the reuse procedure, or stopping reuse. During the eighth episode, a kink was noted in the arterial blood line. Two subsequent hemolytic reactions occurred, and in each kinks were found in the arterial blood line, either in the excess tubing between the blood pump and drip chamber or in the predialyzer. No further hemolytic reactions occurred after changing to a new arterial blood line without redundant tubing and securing all lines. Hemolytic reactions occurring during hemodialysis have many etiologies, including mechanical trauma, which we report may result from kinking of dialyzer lines. With new blood lines on the market, attention to this aspect of dialysis is mandatory.

Abdominal Pain↗
PubMed1996

The fellowship trap.

Explore the source record for details and available documents.

Education, Medical, Graduate↗
PubMed1996

Fat distribution and cardiovascular risk factors in obese adolescent girls: importance of the intraabdominal fat depot.

The regional distribution of body fat has repeatedly been found to be a significant and independent risk factor for cardiovascular disease in both obese men and women. To determine whether abnormalities in the lipid-lipoprotein profile and systolic and diastolic blood pressure are related to specific fat depots early in the course of obesity, we used magnetic resonance imaging to measure accurately intraabdominal and subcutaneous fat masses in 14 obese [body mass index (BMI; in kg/m2) 30 +/- 1.3] and 10 nonobese (BMI: 21 +/- 0.5) adolescent girls matched for age and Tanner stage of development. Intraabdominal and subcutaneous fat depots were two- to threefold greater in obese than in nonobese girls (P < 0.01). Total cholesterol, triacylglycerol, low-density-lipoprotein (LDL) cholesterol, basal insulin, and systolic and diastolic blood pressure were significantly higher in obese adolescent girls than in control subjects. In obese girls, intraabdominal fat but not BMI or waist-to-hip ratio was highly correlated with basal insulin (r = 0.55, P < 0.04), triacylglycerols (r = 0.53, P < 0.03), and high-density-lipoprotein (HDL) cholesterol (r = -0.54, P < 0.04). Femoral adipose tissue was inversely related to triacylglycerol (r = -0.51) and LDL cholesterol (r = -0.56, P < 0.05) concentrations in obese girls. The study indicates that early in the natural history of obese adolescent girls, cardiovascular risk factors are related to the amount of intraabdominal fat.

Abdomen↗
PubMed1996

Bizarre parosteal osteochondromatous proliferation: a review of seven cases.

BACKGROUND: Bizarre parosteal osteochondromatous proliferation (BPOP) is a rare tumour-like condition mostly affecting the tubular bones of the hands and feet. Although it recurs in 50% of cases after local excision, it is a form of heterotopic ossification and its behaviour is otherwise benign. The present study describes seven cases of BPOP collected by the Bone Tumour Registry of New South Wales. METHODS: Clinical data, radiographs and histological specimens collected by the Bone Tumour Registry of New South Wales were examined, and further clinical data were sought from the referring doctor where necessary. RESULTS: Six males and one female aged 18 to 37 years (median 30 years) presented between 1988 and 1995. There were three cases involving the hands, three involving the feet and one involving the distal humerus. Initial treatment was by local excision in all cases. There was local recurrence in three cases. The initial diagnosis was wrong in five of the seven cases. Radiologically, BPOP appears as a well-defined tumour arising directly from the bony cortex, without periosteal reaction or change to the underlying bone. Histologically, a large amount of hypercellular cartilage shows maturation to trabecular bone, which frequently contains spindle cells in the intertrabecular spaces. CONCLUSION: BPOP is a rare, locally recurrent but otherwise benign condition of bone which must be distinguished from more sinister lesions such as parosteal osteosarcoma and chondrosarcoma.

Adolescent↗
PubMed1996

Ethnicity and aged care assessment teams in Queensland.

To examine how functional, medical and psychosocial factors influence the differences in use of community and residential services by Australian-born and ethnic aged persons, all persons (n = 31,737) assessed by aged care assessment teams in Queensland in 1992 and 1993 were surveyed. Subjects were classified as Australian-born, overseas-born in countries where English is the primary language, or overseas-born in countries where English is not the primary language. Factors compared included use of services and residential care both prior to assessment and following assessment, and functional, medical and psychosocial factors. The group with non-English-speaking background were more likely to be both younger and underreferred compared to their proportion in the community. They were more likely to be referred for, and more likely to be recommended for, nursing home placement than the English-speaking groups. They were more commonly referred for assessment because of mental deficit problems, carer stress and/or social isolation, more likely to be diagnosed with dementia and diabetes, and less likely to be diagnosed with respiratory disease and vision disorders. That clients of non-English-speaking background are more likely to be recommended for nursing home placement is probably largely because of more advanced disease at the time of referral and therefore more functional dependence. Aged care assessment teams should increase ethnic communities' awareness of their services, particularly of the benefits of earlier referral.

Activities of Daily Living↗
PubMed1996

Diffuse adenomyosis: comparison of endovaginal US and MR imaging with histopathologic correlation.

PURPOSE: To compare the accuracy of endovaginal ultrasound (US) and magnetic resonance (MR) imaging in the diagnosis of adenomyosis. MATERIALS AND METHODS: The authors prospectively studied 119 consecutive patients undergoing hysterectomy. The endovaginal US scans and MR images were interpreted independently in a double-blind fashion. Imaging findings were compared with those at histopathologic examination. RESULTS: At histopathologic examination, adenomyosis was found in 28 of the 119 patients (24%). Sensitivity and specificity was 89% for endovaginal US and 89% for MR imaging. The positive predictive value was 71% for US and 65% for MR imaging. The negative predictive value was 96% for US and 95% for MR imaging. There was no statistically significant difference between the sensitivities (P = .65) and specificities (P = .75) of endovaginal US and MR imaging. The mean junctional zone (JZ) thickness on MR images in patients with and without proved adenomyosis was 15.0 mm +/- 4.9 and 7.7 mm +/- 3.3, respectively (P < .0001). When receiver operating characteristic curves were applied retrospectively, the optimal JZ value for the diagnosis of adenomyosis with MR imaging was > or = 12 mm. CONCLUSION: Endovaginal US was as accurate as MR imaging in the diagnosis of uterine adenomyosis. Use of a JZ thickness of > or= 12 mm should further optimize the diagnostic accuracy of MR imaging.

Double-Blind Method↗