Search PubMed⌕ Search

Biomedical subjects

C Hood

Publications and source records attributed to C Hood.

At least 19 recordsLinked to original sources

Selection of GM2, fucosyl GM1, globo H and polysialic acid as targets on small cell lung cancers for antibody mediated immunotherapy.

Glycolipids GM2, GD2, GD3, fucosyl GM1, sialyl Lewis a (sLe(a)) and globo H, and polysialic acid on embryonal NCAM, are cell-surface antigens expressed on small cell lung cancer (SCLC) biopsy specimens. They are all candidates for inclusion in a polyvalent, antibody-inducing vaccine or for adoptive therapy with monoclonal antibodies (mAbs) against SCLC. To identify the minimum optimal combination of target antigens on SCLC and to confirm that antibodies against this combination might be able to mediate complement activation and lysis in the majority of cases, we tested ten SCLC cell lines with fluorescence activated cell sorter (FACS) and complement dependent cytotoxicity (CDC) assays using mAbs against these seven target antigens individually or pooled in different combinations. We find that (1) none of these mAbs demonstrated strong FACS reactivity with more than 6 of the 10 cell lines, (2) no mAb had strong CDC reactivity with more than 4 of the cell lines, (3) when the mAbs were pooled, nine cell lines were strongly positive by FACS and nine cell lines were strongly positive by CDC, and (4) mAbs against GM2, FucGM1, globo H and polysialic acid was the minimum optimal combination for inducing FACS reactivity. The addition of mAbs against sLe(a), GD2 and GD3 had no additional impact by FACS and only minimal additional impact in CDC assays. H345, the only cell line that had less than 30% CDC with the four mAb pool was strongly positive by FACS. To understand the lack of correlation between FACS and CDC in the case of H345, the ten cell lines were screened for expression of complement resistance factors CD55 and CD59. Three cell lines were strongly positive for CD55 and eight were strongly positive for CD59. Overall, no correlation was seen between expression of either of these factors on the ten cell lines and sensitivity to CDC. In the case of H345 however, complement resistance of H345 is demonstrated to be mediated primarily by CD59, and in the presence of mAb against CD59, the four mAb MEM-43 pool induced strong (94%) CDC. CD59 inhibits membrane attack complex formation but not activation of earlier complement components. Consequently, all ten cell lines are good targets for complement activation by the four antibody pool and for elimination by effector mechanisms including complement mediated inflammation and opsonization. These findings support our plan to develop a tetravalent vaccine against SCLC targeting GM2, fucosyl GM1, globo H and polysialic acid.

Antibodies, Monoclonal↗

Varicella-zoster virus-infected human sensory neurons are resistant to apoptosis, yet human foreskin fibroblasts are susceptible: evidence for a cell-type-specific apoptotic response.

The induction of apoptosis or programmed cell death in virus-infected cells is an important antiviral defense mechanism of the host, and some herpesviruses have evolved strategies to modulate apoptosis in order to enhance their survival and spread. In this study, we examined the ability of varicella-zoster virus (VZV) to induce apoptosis in primary human dorsal root ganglion neurons and primary human foreskin fibroblasts (HFFs). Three independent methods (annexin V, TUNEL [terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling] staining, and electron microscopy) were used to assess apoptosis in these cells on days 1, 2, and 4 postinoculation. By all three methods, apoptosis was readily detected in VZV-infected HFFs. In stark contrast, apoptosis was not detected during productive VZV infection of neurons. The low-passage clinical isolate Schenke and the tissue culture-adapted ROka strain both induced apoptosis in HFFs but not in neurons, suggesting that this cell-type-specific apoptotic phenotype was not VZV strain specific. These data show that the regulation of apoptosis differs markedly between HFFs and neurons during productive VZV infection. Inhibition of apoptosis during infection of neurons may play a significant role in the establishment, maintenance, and reactivation of latent infection by promoting survival of these postmitotic cells.

Apoptosis↗

Validation of a vision-based, three-dimensional facial imaging system.

OBJECTIVE: The aim of this study was to assess the accuracy of a newly developed three-dimensional (3D) imaging system in recording facial morphology. METHODS: Twenty-one infants with cleft lip each had a full-face alginate impression taken at the time of primary lip repair, and a stone cast was constructed from each impression. Five anthropometric points were marked on each cast. Each cast was digitized, and the 3D co-ordinates of the five points were obtained using a co-ordinate measuring machine (CMM, Ferranti) of documented accuracy (9.53 microm). Each cast was scanned in four positions using a computerized stereophotogrammetry (C3D) system. The five points were located on the 3D images, and their 3D co-ordinates were extracted by three operators. The co-ordinate systems produced by C3D were aligned, via translation and rotation, to match the CMM co-ordinate system using partial ordinary procrustes analysis. The displacements of the adjusted C3D co-ordinates from the reference co-ordinates were then measured. Three different types of errors were identified: operator, system, and registration errors. RESULTS: Operator error was within 0.2 mm of the true co-ordinates of the landmarks. C3D was accurate within 0.4 mm. The average displacement of points over the 21 casts at four positions for the three operators was 0.79 mm (median 0.68). CONCLUSIONS: The presented 3D imaging system is reliable in recording facial deformity and could be utilized in recording cleft deformities and measuring the changes following surgery

Cephalometry↗

LiF:Mg,Cu,P 'pin worms': miniature detectors for brachytherapy dosimetry.

Dose measurements in brachytherapy 192Ir implants are often difficult due to large dose gradients and complex photon spectra. Therefore, tissue-equivalent detectors with a high spatial resolution, such as the highly promising LiF:Mg,Cu,P thermoluminescent detectors (TLDs) are required. It was the aim of the present work to ascertain if miniature LiF:Mg,Cu,P TLDs can effectively measure the dose distribution around 192Ir implants. 'Pin worm' TLDs (type MCP, diameter 0.6 mm, length 2 mm) were compared with GR-200R (SSDL, Beijing) rods cut in half. The TLDs were tested for reproducibility and energy dependence using high dose rate (HDR) and low dose rate (LDR) brachytherapy units. 192Ir measurements were performed in a tissue equivalent phantom accommodating hollow needles and catheters routinely used in brachytherapy. Pin worms had an average reproducibility of less than +/-2% (1 SD) and a detection limit of less than 10 microGy. The small dimensions of the pin worms allowed their placement within brachytherapy needles and catheters. The measured relative dose distribution was in good agreement with the predictions of a computerised treatment planning system (ADAC Pinnacle); however, limitations in the TLD energy correction did not allow for absolute dose comparison.

Brachytherapy↗

What is the prevalence of rheumatic disorders in general medical inpatients?

It has been suggested that rheumatological disorders are underdiagnosed in patients with medical problems and that this might be rectified by incorporating a standard brief screening examination as part of the routine assessment of all patients admitted to hospital with medical conditions. Therefore the GALS screening examination was used to assess the prevalence of rheumatic disease in 100 patients admitted with acute medical problems and in a further 100 in the rehabilitative phase of their disease. The nature of locomotor dysfunction in all patients with a positive result was defined by an independent review and then sensitivity and specificity of the screening test was calculated for rheumatic disease in both populations. The median age of the two populations were 63 and 78 years respectively, with more females in the rehabilitation group. The overall prevalence of a positive screening test was 53% in the acute and 94% in the chronic disease groups, although the false positive rate in the rehabilitation patients was 30% due to factors other than rheumatic disorders limiting locomotor function (mainly orthopaedic and neurological conditions). The diagnosis of a rheumatological disorder was made de novo in a significant minority (10%) of patients and was usually amenable to treatment. The commonest rheumatic disorder was osteoarthritis which accounted for 55% of all rheumatic disease, followed by inflammatory joint disease (16%), and osteoporosis (12%). In addition to osteoporosis, Paget's disease of bone and polymyalgia rheumatica were found more frequently in those patients undergoing rehabilitation than in those admitted with an acute medical problem. A number of clinically important associations between medical and rheumatic disorders were found, such as stroke disease with shoulder capsulitis and heart failure with gout. The sensitivity of the GALS screening test was extremely high (92% and 100%), while its specificity fell in the rehabilitation group from 83% to 17%. None the less, it is felt that this study indicates that the routine use of this test should be considered as part of the assessment of all hospitalised patients with medical problems, whether acute or chronic.

Acute Disease↗

The effect of longer-term creatine supplementation on elite swimming performance after an acute creatine loading.

We investigated the effect of an acute creatine loading (25 g per day for 4 days) and longer-term creatine supplementation (5 g of creatine or 5 g of placebo per day for 2 months) on the performance of 22 elite swimmers during maximal interval sessions. After the acute creatine loading, the mean of the average interval swim times for all swimmers (n = 22) improved (44.3+/-16.5 s before vs. 43.7+/-16.3 s after supplementation; P<0.01). Three of the 22 swimmers did not respond positively to supplementation. After 2 months of longer-term creatine supplementation or placebo, neither group showed a significant change in swimming performance (38.7+/-13.5 s before vs. 38.7+/-14.1 s after for the creatine group; 48.7+/-18.0 s before vs. 48.7+/-18.1 s after for the placebo group). We conclude that, in elite swimmers, 4 days of acute creatine loading improves swimming performance significantly when assessed by maximal interval sessions. However, longer-term supplementation for 2 months (5 g of creatine per day) did not benefit significantly the creatine group compared with the placebo group.

Adult↗

Basal cell carcinoma in an elderly woman.

It is important to ensure that the position of the camera and the light source does not produce uneven illumination. Hot spots are caused by the light source being much closer to certain areas of the subject than others.

Aged↗

Hand, foot and mouth disease.

Standardisation is vital if the clinical images are to be used for monitoring any changes in the patient's condition. The two images can be cut and mounted in one 35 mm mount for comparison.

Child, Preschool↗

Herpes ophthalmicus.

Always ensure that patient consent is obtained before any type of photography is undertaken, as the patient has the right to decide what is to happen to the images.

Herpes Zoster Ophthalmicus↗

Finger clubbing.

Reflectors can be made easily and used to illuminate areas of the photograph that are in shadow, so giving the equivalent of an extra light source. Choosing the correct background guards against colour cast and distracting shadow.

Adult↗

Lentigo maligna.

Remember to be aware of illumination and how the flash reflex may affect the final photograph.

Humans↗

Dacrocystitis.

In clinical photography, two views are often better than one to maximise the amount of information available to the viewer. Photographers should not endeavour to record everything in one shot.

Acute Disease↗

Enterobius vermicularis.

The benefits of a ring flash in photographing an orifice can be seen in this interesting case where the main subject area is clearly visible. When photographing minors, the legal implications of the subject material needs to be considered to avoid contravening the Protection of Children Act.

Anal Canal↗

Ethmoidal polypi.

Explore the source record for details and available documents.

Ethmoid Sinus↗