PubMed Health⌕ Search

Biomedical subjects

H Adams

Publications and source records attributed to H Adams.

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

The role of complement in the pathogenesis of postpartum thyroiditis: ultrasound echogenicity and the degree of complement-induced thyroid damage.

Postpartum thyroiditis (PPT) is a transient autoimmune thyroiditis occurring during the postpartum year that is characterized by circulating antithyroid antibodies, abnormal thyroid ultrasound echotexture, and episodes of hyperthyroidism, hypothyroidism, or both. In this study we examined the relationship between lymphocytic thyroiditis, as indicated by echotexture changes, and complement-activating thyroid autoantibodies. Thyroid ultrasound echotexture, thyroid function, and bioactive (complement-activating) thyroid peroxidase (TPO) antibodies have been measured in a group of 63 TPO antibody-positive women during the postpartum year. When the maximum bioactive TPO antibody activity recorded was compared with echogenicity and thyroid status, there was a correlation between hypoechogenicity, elevated antibody activity, and abnormal thyroid status (r = 0.72, p < 0.001). However, 7 cases showed severe ultrasound changes in the absence of any thyroid dysfunction (3 of these cases showed normal bioactive antibody activity), while 4 (all hyperthyroid PPT) showed thyroid dysfunction in the absence of any ultrasound changes. Within the euthyroid ultrasound normal group, bioactive TPO antibody activity remained low throughout the postpartum year. Antibody activity in the hypoechogenic euthyroid women was significantly elevated (p < 0.001) compared with the echo normal group, but was indistinguishable from the activity curve obtained in women whose PPT included a hypothyroid phase. The determination of echotexture by thyroid ultrasonography gives a useful, noninvasive measure of the degree of thyroiditis in these women. However, as a significant number of cases with severe changes in echotexture remained euthyroid, we conclude that the development of thyroid dysfunction is not an inevitable consequence of lymphocytic thyroiditis during the postpartum and suggests that other factors must also be involved in progression to overt thyroid dysfunction.

Autoantibodies↗
PubMed1995

Case report: paediatric intramuscular haemangiomata--don't overlook the phlebolith!

Three children presented with soft tissue masses which were clinically suspected to be soft tissue sarcomas. The identification of phleboliths on initial radiological studies should have suggested the correct diagnosis of benign intramuscular haemangiomata. Subsequent referral to a paediatric oncological unit, and the unnecessary parental anxiety so generated, could have been avoided.

Calculi↗
PubMed1994

The iodide perchlorate discharge test in women with previous post-partum thyroiditis: relationship to sonographic appearance and thyroid function.

BACKGROUND: Post-partum thyroid disease occurs in 50% of anti-thyroid peroxidase (TPO) antibody positive women (detected at 16 weeks' gestation) and is characterized by a transient episode of hyper, hypo or hyper-hypothyroidism. In approximately 20% of these women the hypothyroidism is permanent. However, the extent of long-term thyroid dysfunction, possibly mediated by immune attack, in those anti-TPO Ab + ve women who have had only transient or no thyroid dysfunction during the postpartum period is not clear. OBJECTIVE: We have therefore studied the frequency of iodide organification defects by iodide perchlorate discharge testing, and of thyroid morphological abnormalities by ultrasound scanning in euthyroid women following their episode of post-partum thyroiditis (PPT). DESIGN: The study group comprised 17 women with previous PPT (PPT + ve) and 12 women who had positive anti-TPO antibodies during pregnancy but who did not develop PPT (PPT - ve). Women were studied 15-47 months following their episode of PPT. RESULTS: Iodide perchlorate discharge tests were positive (more than 10% discharge) in 7 (41%) PPT + ve and 5 (42%) PPT-ve subjects (P = NS). Morphological abnormalities on thyroid ultrasound were detected in 7 of 14 (50%) PPT + ve and 7 of 9 (77%) PPT - ve subjects (P = NS). There was a strong association between abnormalities of iodide organification and morphology: of 11 subjects with positive iodide perchlorate discharge tests, 10 had abnormal (positive) ultrasound scans; of 12 subjects with negative iodide perchlorate discharge tests 8 had negative ultrasound scans (P = 0.013, Fisher's exact test). CONCLUSIONS: Long-term subtle defects of thyroid function and morphology are common in women with anti-TPO antibodies in pregnancy, whether or not they develop post-partum thyroiditis. The clinical significance of these findings is unclear but a continuing thyroid pathological process is suggested.

Adult↗
PubMed1994

Serum thyroglobulin: an early indicator of autoimmune post-partum thyroiditis.

OBJECTIVE: The aim of this study was to assess whether autoimmune thyroid damage in post-partum thyroiditis was accompanied by a significant rise in the concentration of thyroglobulin in the serum and whether its measurement could be useful in the prediction of the risk and severity of an episode of post-partum thyroid dysfunction. PATIENTS: Fifty-one women, who had taken part in a larger survey of post-partum thyroiditis, were selected at random for this study. Fourteen women without elevated circulating thyroid autoantibodies and 21 with raised thyroid autoantibodies remained euthyroid throughout the post-partum year. A third group of 14 women had raised thyroid autoantibody levels and showed one or more episodes of thyroid dysfunction during the course of the first year post partum. MEASUREMENTS: Thyroid autoantibodies were measured by ELISA, free T3 and free T4 by the Amerlex M method and TSH by an immunoradiometric method. Serum thyroglobulin was measured by a method free from interference by circulating endogenous thyroglobulin autoantibodies. Thyroid ultrasonography was performed using a General Electric RT3600 scanner operating at 7.5 MHz. RESULTS: Fourteen control women had a mean serum thyroglobulin concentration of 3.3 micrograms/l (SD 4.4; range < 1-12 micrograms/l; 95% confidence interval up to 6.0 micrograms/l). Twenty-one thyroid autoantibody positive euthyroid women had a mean serum thyroglobulin level of 5.8 micrograms/l (SD 6.2; range < 1-36 micrograms/l) which was not significantly different from that seen in the control group. Sixteen thyroid autoantibody positive women who showed one or more episodes of thyroid dysfunction during the post-partum period had a mean serum thyroglobulin of 31 micrograms/l (SD 24.8; range up to 88 micrograms/l) and this was significantly elevated compared with both the control and antibody positive groups (P < 0.001). Serum thyroglobulin concentrations at 3 months post partum correlated with the degree of post-partum hypothyroidism (as indicated by the maximum TSH and the minimum free thyroxine concentrations post partum) and, in those cases where thyroid ultrasound examinations were performed, with the degree of lymphocytic infiltration of the thyroid gland. CONCLUSIONS: The data presented in this paper confirm the destructive nature of post-partum thyroiditis and indicate that the measurement of serum thyroglobulin concentration could assist in the identification of those women at risk of post-partum thyroiditis.

Autoantibodies↗
PubMed1994

Preoperative staging of carcinoma of the bronchus: can computed tomographic scanning reliably identify stage III tumours?

BACKGROUND: The aim of preoperative computed tomographic (CT) assessment of patients with carcinoma of the bronchus is to stage the tumour accurately, and forewarn the surgeon of any possible local extrapulmonary extension of tumour in patients considered to have potentially resectable disease. The ability of CT scanning to differentiate between conventionally resectable lung cancer (TNM stages I and II), locally advanced but resectable lung cancer (TNM stage IIIa), and locally advanced but unresectable lung cancer (TNM stage IIIb) was determined in a group of patients accepted for surgery. METHODS: Computed tomographic scans of 110 patients who underwent thoracotomy for intended resection of carcinoma of the bronchus, including 52 cases with stage III and 58 cases with stage I or II disease, were reviewed and the CT features and radiological interpretations correlated with the surgical and pathological findings. RESULTS: Thirteen CT scans were judged not to have been of diagnostic quality: of the remaining 97 cases 45 had stage III lung cancer, of whom 30 had successful resections, and 52 had stage I or stage II tumours. There was no difference in the frequencies of CT observations--including contiguity of tumour and mediastinum or chest wall, apparent mediastinal or chest wall invasion, proximity of tumour to the carina, mediastinal nodal enlargement, pulmonary collapse or consolidation and pleural effusion--in patients with stage I/II disease and patients with stage III disease. Similar results were found when the same observations were compared in all patients with resected disease and those with unresectable tumour. Sensitivity and specificity of CT was 27% and 96% respectively for tumour unresectability, 50% and 89% for mediastinal invasion, 14% and 99% for chest wall invasion, and 61% and 76% for mediastinal nodal metastases. Only 19 of 45 stage III tumours were correctly identified as being stage III and resectable or unresectable. CONCLUSIONS: In patients being considered for thoracotomy for resection of lung cancer, CT scanning used as the sole method of staging is of limited value for differentiating between stage I/II and stage III tumours. Patients should not be denied the opportunity for curative surgery on the basis of equivocal CT signs.

Carcinoma, Bronchogenic↗
PubMed1994

Client variables associated with selection and outcome in a methadone tapering program.

Based on archival information on 36 methadone maintenance patients, indicators of success in a methadone tapering program were investigated. None of the variables selected for study were found to differentiate successful from unsuccessful taperers. However, patients who were offered the opportunity to participate in the tapering program had significantly fewer years of heroin use prior to their admittance to a methadone maintenance program than patients in the general methadone maintenance population. In addition, the racial composition of patients attempting to taper included significantly fewer Black patients than the racial composition of the general methadone maintenance population. Possible explanations are offered.

Adult↗
PubMed1993

The effect on apparent size of simulated pulmonary nodules of using three standard CT window settings.

This study was undertaken to determine whether three commonly used combinations of CT display window settings permit accurate measurement of pulmonary nodule size during thoracic CT examination. Forty-five rounded nodules of synthetic material of approximate soft tissue density (+70 Hounsfield units; HU), varying in size from 5.8 mm to 21.4 mm, were suspended in surgical gauze (-900 HU to -950 HU) to simulate pulmonary nodules. CT images were obtained for each nodule using 10 mm and 2 mm CT collimation and the size of each nodule was measured at three window settings: (a) 'soft tissue setting': window width (WW) 400 HU, window level (WL) +20 HU; (b) 'lung setting'. WW 850 HU, WL -750 HU; (c) 'broad lung setting': WW 1350 HU, WL -550 HU. Measurements obtained using either lung setting were highly accurate irrespective of collimation while measurements obtained using soft tissue settings were inaccurate. The choice of display window settings is an important consideration when CT is used to assess the size of pulmonary nodules.

Humans↗
PubMed1993

The computed tomographic appearances in chronic berylliosis.

Computed tomography (CT) of the thorax was performed in eight patients with chronic berylliosis. The pulmonary CT features were variable and included pulmonary nodularity, and patterns consistent with upper lobe fibrosis or diffuse interstitial fibrosis. Mediastinal or hilar lymphadenopathy was shown in three cases. CT clearly demonstrates the pattern and distribution of pulmonary and mediastinal involvement in chronic pulmonary berylliosis but the appearances are non-specific.

Adult↗
PubMed1993

The computed tomographic appearances of angiosarcoma of the liver.

The computed tomographic (CT) appearances are described in five vinyl chloride workers with hepatic angiosarcoma subsequently confirmed at post-mortem. The tumour was multifocal in four patients. Non-enhanced scans were available in four cases showing hypodense masses relative to background liver. Dynamic scanning during intravenous contrast injection was performed in all five patients showing peripheral or central foci of enhancement within the tumour. On delayed post-contrast scans performed in three patients the angiosarcoma became wholly or partly isodense compared to normal liver. The CT appearances of angiosarcoma of the liver are non-specific but are consistent with a vascular tumour, and the differential diagnosis is discussed. Due to the vascularity of angiosarcoma, liver biopsy may be hazardous and can be avoided when there is a history of exposure to vinyl chloride monomer and the CT findings are consistent with the diagnosis.

Aged↗
PubMed1993

Energetics and kinetics of maltose transport in Saccharomyces cerevisiae: a continuous culture study.

In Saccharomyces cerevisiae, maltose is transported by a proton symport mechanism, whereas glucose transport occurs via facilitated diffusion. The energy requirement for maltose transport was evaluated with a metabolic model based on an experimental value of YATP for growth on glucose and an ATP requirement for maltose transport of 1 mol.mol-1. The predictions of the model were verified experimentally with anaerobic, sugar-limited chemostat cultures growing on a range of maltose-glucose mixtures at a fixed dilution rate of 0.1 h-1. The biomass yield (grams of cells.gram of sugar-1) decreased linearly with increasing amounts of maltose in the mixture. The yield was 25% lower during growth on maltose than during that on glucose, in agreement with the model predictions. During sugar-limited growth, the residual concentrations of maltose and glucose in the culture increased in proportion to their relative concentrations in the medium feed. From the residual maltose concentration, the in situ rates of maltose consumption by cultures, and the Km of the maltose carrier for maltose, it was calculated that the amount of this carrier was proportional to the in situ maltose consumption rate. This was also found for the amount of intracellular maltose. These two maltose-specific enzymes therefore exert high control over the maltose flux in S. cerevisiae in anaerobic, sugar-limited, steady-state cultures.

Adenosine Triphosphate↗
PubMed1993

Percutaneous needle biopsy of the mediastinum: review of 94 procedures.

BACKGROUND: A number of reports of radiologically guided percutaneous biopsy of mediastinal masses have been described but techniques have varied, particularly the type of needle used. In this study mediastinal biopsies with fine aspiration needles and cutting needles have been compared, sometimes in the same patient. The results are reviewed with particular emphasis on the choice of biopsy needle and its influence on pathological diagnosis. METHODS: A retrospective review was undertaken of radiologically guided mediastinal biopsies performed between 1981 and 1991. RESULTS: Sixty fine needle aspiration biopsies (FNA) and 34 Tru-Cut biopsies of mediastinal masses were performed in 75 patients with fluoroscopic or computed tomographic guidance. Overall sensitivity and specificity in terms of diagnosis of malignant disease were 90% and 100% respectively for FNA biopsies, and 96% and 100% for Tru-Cut biopsies. Diagnostic accuracy in terms of precise diagnosis of the malignant or benign nature of a mass and its origin was 77% for FNA biopsies and 94% for Tru-Cut biopsies. For FNA biopsies sensitivity and accuracy were higher for carcinomatous lesions (96% and 88%) than for noncarcinomatous lesions (81% and 69%). The only significant complication encountered was a pneumothorax following a biopsy which required intercostal drainage. CONCLUSIONS: Radiologically guided percutaneous needle biopsy is a safe procedure which provides useful diagnostic information in the majority of cases. Fine needle aspiration techniques usually suffice for carcinomatous lesions but a cutting needle biopsy should be performed whenever possible when lymphoma, thymoma, or neural masses are suspected to obtain larger specimens for more accurate histological diagnosis.

Adolescent↗
PubMed1993

Los Angeles organ sharing: twenty-six-year report.

1. The Los Angeles Transplant Society and the Regional Organ Procurement Agency of Southern California (ROPA) was established in November 1967. ROPA was the first such organization in the United States. 2. The use of simple cold storage and shipment of kidneys by commercial airline resulted from pioneering concepts developed in the Los Angeles area from 1968-1969. 3. In the 26-year period of ROPA's operation, it has coordinated 8,446 kidney transplants. 4. All kidneys transplanted in 1993 were allocated according to the UNOS point system. 5. Allocating all kidneys under the point system has not significantly disadvantaged either large or small transplant centers in the greater Los Angeles area. 6. Racial distribution of recipients: 13% Black (compared with Los Angeles population of 12% and 6% donor population). Blacks represent 20% of the recipient waiting list. Hispanic recipients were 31% (compared to Los Angeles population of 40% and donor population of 30%). Hispanics comprised 28% of the waiting list. 7. The average waiting times for centers in the Los Angeles area ranged from 14-19.4 months. Transplanted patients waited an average of 16.3-22.1 months. 8. "Required request" had a significant effect on the number of referrals but did not produce a meaningful increase in the number of kidneys transplanted.

Cryopreservation↗
PubMed1992

Computed tomographic assessment of patients following radical surgery for malignant mesothelioma.

Serial computed tomographic (CT) scans of the thorax and upper abdomen were performed in eight patients following radical surgery (pleuro-pneumonectomy) for diffuse malignant mesothelioma of the pleura. The post-operative appearances included a well defined membrane lining the pleuro-pneumonectomy space in seven cases; in two cases this resembled the original tumour. In six patients there was upward abdominal visceral displacement on the side of the surgery due to diaphragmatic resection; this resulted in contralateral mediastinal shift in four patients. One patient required a diaphragmatic prosthesis which produced a distinctive CT appearance. CT suggested recurrent mesothelioma in five cases. Although two patients had evidence of intrathoracic recurrence, in three patients the only feature was the non-specific finding of abdominal ascites. The normal CT appearances after pleuro-pneumonectomy should be recognized to facilitate radiological interpretation. With careful application CT is of value for the assessment of recurrent disease in patients following radical surgery for malignant mesothelioma.

Adult↗
PubMed1992

The sonographic appearances in postpartum thyroiditis.

During the postpartum period about 50% of women with circulating thyroid autoantibodies develop a transient autoimmune thyroiditis. To determine the sonographic appearances in postpartum thyroiditis (PPT), serial ultrasound (US) scans of the thyroid were performed in 135 postpartum women who were divided into three clinical groups: Group 1, 37 antibody positive subjects who developed PPT; Group 2, 28 antibody positive subjects in whom thyroid function remained normal; Group 3, 70 antibody negative controls. Thyroid hypoechogenicity was observed in 14/31 patients (45%) who were scanned between 4 and 8 weeks postpartum and who subsequently developed PPT (Group 1) compared with 4/24 patients (17%) in Group 2 (P less than 0.05) and 1/65 patients (1.5%) in Group 3 (P less than 0.001). In antibody positive patients, the positive predictive value of an abnormal scan during this period was 78%. Between 15 and 25 weeks postpartum thyroid hypoechogenicity was present in 32/37 patients (86%) in Group 1 compared with 11/28 patients (39%) in Group 2 (P less than 0.001) and 2/70 patients (3%) in Group 3 (P less than 0.001). Sonographic abnormality persisted beyond 32 weeks postpartum in 36/41 antibody positive patients (87%) who had exhibited thyroid hypoechogenicity earlier during the study and who had late scans. The characteristic US appearance in PPT is thyroid hypoechogenicity. The role of sonography in the prediction, diagnosis and follow up of patients with PPT is discussed.

Autoantibodies↗
PubMed1992

The computed tomographic appearances in pulmonary artery atresia.

Isolated pulmonary artery atresia is an uncommon congenital abnormality. Plain radiography and ventilation/perfusion lung scintigraphy may suggest the diagnosis but pulmonary angiography has traditionally been recommended for confirmation. The computed tomographic (CT) appearances of four patients with isolated atresia of a pulmonary artery are described. In each case the atretic segment of the abnormal vessel could be identified. Other CT findings included reduction of volume of the involved hemithorax, increased density of the affected lung, a small hilum, and an abnormal pulmonary vascular pattern thought to be due to the collateral systemic arterial supply to the intrapulmonary branches of the atretic pulmonary artery. The diagnosis of isolated pulmonary artery atresia can be made using dynamic, contrast enhanced CT without recourse to more invasive procedures.

Adolescent↗
PubMed1992

Massive pleural effusion: an unusual presentation of Castleman's disease.

Giant lymph node hyperplasia (Castleman's Disease) is a rare cause of pleural effusion. We report the case of a 51 yr old West Indian male, who presented with a recurrent massive pleural effusion, due to a tumour arising from the pleura. He underwent parietal pleurectomy and subtotal excision of the tumour. Histological analysis of the specimen showed the features of multicentric Castleman's disease. Nine months following surgery he remains well, with no recurrence of the effusion.

Castleman Disease↗
PubMed1991

An appraisal of CT pulmonary density mapping in normal subjects.

Modern computed tomographic (CT) scanners have post-processing facilities which allow pixels within a selected density range to be highlighted. It has been suggested that using this technique to highlight regions of low CT density (-900H to -1000H) can locate and quantitate areas of pulmonary emphysema. To establish the variability of the lung density map in normal subjects this technique was used in 17 patients with no evidence of structural lung disease on full respiratory function testing. Mean CT lung density varied from -770H to -875H (overall mean -817H). The percentage cross-sectional area in the low density range -900H to -1000H varied from 0.6% to 58% (mean 15.3%). In two further groups of 12 subjects the influence of CT slice thickness and intravenous contrast administration on the lung density map was evaluated. The use of narrower collimation led to an increase in mean cross-sectional area within the low density range from 9.6% to 16.1% (P less than 0.05). The use of intravenous contrast led to a reduction in mean cross-sectional area within the range from 8.9% to 3.3% (P less than 0.01). There is considerable variability in the lung density map of normal individuals and the method is also dependent on radiographic technique. These factors should be taken into account when considering the use of CT lung density mapping for the assessment of pulmonary disease.

Adult↗