PubMed Health⌕ Search

Biomedical subjects

H Smyth

Publications and source records attributed to H Smyth.

At least 19 recordsLinked to original sources
PubMed2006

Spray pattern analysis for metered dose inhalers I: Orifice size, particle size, and droplet motion correlations.

Factors that influence spray pattern measurements of pressurized, metered-dose inhalers have been evaluated. Spray patterns were correlated with changes in actuator orifice diameter, particle size profiles, and calculated estimates of particle-size dynamics of plumes during a spray. Spray patterns, regardless of actuator orifice size, were ellipsoid in the vertical direction. Measures of elliptical ratio, major axis, and minor axis were significantly influenced by orifice size in a non-linear fashion over the range of orifice sizes investigated. Spray patterns also correlated with particle size profile and spray geometry measurements. Spray distribution asymmetry may be related to droplet evaporation and sedimentation processes. However, the spray patterns did not appear sensitive to changes in gravitational force acting on the plume. Instead, it is postulated that elliptical spray patterns may have dependence on fluid dynamic processes within the inhaler actuator. Developing an understanding of these processes may provide a basis for developing spray pattern tests with relevance to product performance.

Aerosol Propellants↗
PubMed2005

Prognostic indicators in an aggressive pituitary Crooke's cell adenoma.

OBJECTIVE: To investigate prognostic indicators in an aggressive Crooke's cell adenoma of the pituitary. METHODS: The surgically removed tumor was studied by histology, immunohistochemistry and transmission electron microscopy. RESULTS: An aggressive invasive sellar tumor removed by repeated surgeries from a 43-year-old woman with pituitary related Cushing's disease was classified as a Crooke's cell adenoma of the pituitary. The application of several cell proliferation markers confirmed the aggressive nature of the tumor. CONCLUSIONS: The investigation of the present case provides additional evidence that pituitary Crooke's cell adenomas may possess aggressive behavior.

Adenoma↗
PubMed2004

Acute compartment syndrome of the anterior thigh following quadriceps strain in a footballer.

A rare case is presented of acute anterior compartment syndrome in the thigh of a footballer caused by an acute quadriceps strain, exacerbated by poor first aid and alcohol ingestion. Decompressive fasciotomy with subsequent split skin grafting of the wound defect resulted in a satisfactory outcome. The diagnosis requires a high index of suspicion lest it be overlooked with inevitably disastrous consequences.

Acute Disease↗
PubMed2002

Total knee arthroplasty in patients with severe haemophilia.

We reviewed the perioperative records of haemophiliac patients who underwent total knee replacement (TKR) over the period 1990-1999 and followed up the surviving patients. Nine knees were replaced in eight patients. Seven of the nine patients did not require blood transfusion. Mean perioperative haemoglobin drop was 2.9 g/dl. There were no significant complications. All surviving patients (eight TKRs) were reviewed clinically using a standard scoring system. The mean follow-up period was 51 months. All patients scored excellent (>90/100) in the functional category. The frequency of haemarthroses fell significantly from the rate experienced prior to TKR, and pain scores were zero.

Adult↗
PubMed2002

Massive pseudotumour resection with recombinant factor VIIa (NovoSeven) cover.

Surgical resection is the only definitive treatment for haemophilic pseudotumour. For patients with high- responding factor (F)VIII inhibitors, the lack of reliable by-passing agents in the past has meant that surgery has been avoided in favour of conservative measures. The development of recombinant factor VIIa (rFVIIa) has revolutionized the management of surgery in these patients. We document the first successful report of the surgical resection of a massive pseudotumour in a patient with high responding FVIII inhibitors using rFVIIa to achieve haemostasis. Serial post-operative measurements indicated that FVII coagulation activity (FVII:C) levels were more sensitive to rFVIIa dose changes than the prothrombin time.

Adult↗
PubMed2000

Acute compartment syndrome of the forearm in association with ulnar shortening osteotomy: a case report.

A 41-year-old man experienced severe pain in the forearm after undergoing ulnar shortening osteotomy to treat positive ulnar variance, a complication of a fracture of the distal end of the radius. The patient had compartment syndrome with compartment pressure of 55 mm Hg. A decompressive fasciotomy of the volar compartment provided total relief of pain and, subsequently, full recovery of all functions. We report the case and discuss the serious nature of compartment syndrome, its associated complications, and methods of diagnosis and management.

Accidental Falls↗
PubMed1997

Failure of femoral nailing in the elderly.

Failure of fixation of a fracture of the mid-shaft of the femur in a 73-year-old male occurred 4 weeks after insertion of a reamed Grosse-Kempf nail. The oblique locking screw had cut out, despite having been correctly sited at the primary operation. A satisfactory result was obtained following open nailing using an AO nail. Two transverse proximal locking screws provide more certain fixation in osteoporotic bone of elderly patients.

Accidental Falls↗
PubMed1995

Absorbable sutures in tendon repair. A comparison of PDS with prolene in rabbit tendon repair.

The risks of foreign implantation may be avoided in tendon repair by the use of absorbable sutures, for example polydioxanone. In this study, the in vivo tensile strength half-life of 4/0 polydioxanone was found to be approximately 4 weeks. Using a rabbit model, we compared polydioxanone tendon repairs with polypropylene tendon repairs. Unilateral flexor digitorum longus repairs were performed on 46 rabbits using either polydioxanone or polypropylene. Tendons were harvested at 3 days, 2 weeks and 4 weeks and the tensile breaking strengths were obtained. 30 intact rabbit flexor digitorum longus tendons and 20 freshly repaired tendons were also tested. By 4 weeks, the repair strength had increased eight-fold from approximately 20 N to 166 N. The sutures made little contribution to the overall strength of a 4-week-old repair. There was no significant difference between polydioxanone and polypropylene repairs at any stage. These results show that polydioxanone repairs were as strong as polypropylene during the first critical weeks of tendon healing.

Absorption↗
PubMed1994

In situ hybridization study of estrogen receptor messenger ribonucleic acid in human adenohypophysial cells and pituitary adenomas.

Estrogen receptor (ER) was demonstrated in nontumorous and adenomatous human pituitaries by autoradiography and biochemical assays. In the present study, we investigated ER mRNA by in situ hybridization applied on paraffin section of 9 nontumorous pituitaries obtained at surgery or autopsy and 109 surgically removed adenomas. In nontumorous pituitaries, in situ hybridization combined with immunocytochemistry revealed hybridization signal in GH-, PRL-, ACTH-, TSH-, and LH/FSH-immunoreactive cells, with the highest intensity in PRL-immunoreactive cells. ER mRNA was also localized in Crooke's cells, corticotrophs extending to posterior lobe, cells lining the pars intermedia cavities, and squamous nests of pars tuberalis. The neurohypophysis, endothelium, and connective tissue expressed no ER gene. ER mRNA was present in all adenoma types, including somatotroph, lactotroph, mixed somatotroph-lactotroph, mammosomatotroph, acidophil stem cell, functioning and silent corticotroph, thyrotroph, gonadotroph, null cell adenomas, and oncocytomas. The strongest signal was seen in some lactotroph and mammosomatotroph adenomas. In 9 lactotroph adenomas exposed to bromocriptine (long-acting repeatable injectable form), the hybridization signal was weak or absent, suggesting that suppression of ER gene plays a role in the inhibition of PRL synthesis and tumor growth.

Adenoma↗
PubMed1992

Preventive health behaviours among parents of infants aged four months.

Six preventive health behaviours have been frequently identified as having the potential to reduce mortality and morbidity during infancy: breast-feeding until the age of six months; no solid food until after four months of age; immunisation against whooping cough, diphtheria, poliomyelitis and tetanus; the use of a baby capsule to restrain the infant when travelling in a motor vehicle; regular attendance at a health care provider for preventive health checks; and no maternal smoking. This study surveyed 191 primiparous women four months after the birth of their babies to explore the proportion of parents who perform the recommended preventive health behaviours and the association among the behaviours. Thirty-nine per cent of the women reported that they were no longer breast-feeding by the time their infant was four months old; 35 per cent had introduced solids before 16 weeks of age; 35 per cent did not always use a baby capsule when travelling with their baby in their car, 25 per cent did not regularly attend the early childhood health centres and 22 per cent smoked. Forty-eight per cent of the sample were performing four or fewer of the six preventive health behaviours and 21 per cent were performing three or fewer. The relationship between performing each preventive health behaviour and a range of demographic variables was investigated. A logistic regression indicated that performing three or fewer of the health behaviours was associated with lower levels of education, having public health insurance and being born in a country other than Australia.

Adult↗
PubMed1991

A critical analysis of the use of sialic acid determination in the diagnosis of malignancy.

The measurement of serum sialic acid in sera from individuals with leukemia, breast, gastrointestinal, lung and bladder cancers, brucellosis and manic depression is described. The serum sialic acid levels were also examined in mice bearing Landschutz ascites tumours. The presence of sialic acid-enriched glycopeptides in serum was shown. The results indicate that while sialic acid may be significantly elevated in sera of some tumour-bearing individuals, it is not solely tumour-derived. Its application as a tumour marker is limited and requires critical analysis.

Animals↗
PubMed1987

Release of malignancy-related fucopeptides from ascites tumour cells in association with membrane vesicles.

Membrane vesicles were found to be released from Landschütz ascites cells in vivo and in vitro. Vesicle fractions were highly enriched in the large fucopeptides which are a known feature of malignant cell membranes. Incubation with trypsin in vitro is commonly used to release these fucopeptides from tumour cells. The present results show that the enzyme acts by increasing the release of lipid vesicles enriched in these components, rather than by liberating soluble tryptic products. Thus, the parent molecules in the cell would appear to be integral membrane proteins which are insensitive to direct cleavage by trypsin.

Animals↗
PubMed1982

Total and surface-located sialic acid levels in normal and leukaemic lymphocytes: relationship to T and B cell nature and to location in vivo.

Unfractionated normal blood lymphocytes (predominantly T lymphocytes) showed significantly elevated total and neuraminidase-susceptible sialic acid compared with CLL lymphocytes (predominantly B lymphocytes). T-enriched fractions from normal blood contained about three-fold the sialic acid content of the corresponding T-depleted fractions, and similarly low values were also obtained for T-depleted fractions from tonsils. Thus the reduced sialic acid levels in CLL lymphocytes appear to be due to their B cell nature. In contrast to the situation in normal peripheral venous blood, tonsillar T and B cells did not differ markedly in sialic acid content, suggesting that for T cells maturity and/or location in vivo are important determinants of this parameters. Results with calf thymocytes were in agreement with this. Sialic acid was estimated in malignant B and T lymphoblasts. Shedding of sialic acid-containing moieties from lymphocytes was also examined.

B-Lymphocytes↗
PubMed1980

Separation of viable from nonviable cells using a discontinuous density gradient.

When a suspension containing a mixture of viable and nonviable cells is layered over a dense ficoll-metrizoate solution and centrifuged, most of the viable cells are retained at the interface above the dense solution; whereas most of the nonviable cells are distributed in other fractions. The cells recovered from the interface are capable of subsequent growth in culture.

Animals↗