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Biomedical subjects

H J Shaw

Publications and source records attributed to H J Shaw.

At least 19 recordsLinked to original sources
PubMed1998

Non-invasive diagnosis of pregnancy in wild black rhinoceros (Diceros bicornis minor) by faecal steroid analysis.

The objective of this study was to determine whether faecal progestagen measurement could be used to diagnose pregnancy in wild black rhinoceros cows. Immunoreactive 20alpha-progestagens were measured in faecal samples collected regularly (one or two times times per week) from pregnant and non-pregnant wild black rhinoceros females (n = 6) in Zimbabwe. Fresh dung piles deposited by the study animals were serially sampled during prolonged periods of tracking with local game scouts. Samples were stored frozen, and dried prior to methanol extraction. Immunoreactivity in faecal extracts was measured with a 20alpha-dihydroprogesterone enzyme immunoassay and was shown to reflect circulating progesterone concentrations. Mean concentrations of faecal 20alpha-progestagens during each month of gestation were significantly higher than faecal concentrations in non-pregnant animals (P<0.05), except during the second month of gestation. Faecal 20alpha-progestagens remained 5-10 times higher than concentrations in non-pregnant animals from the 4th to 15th month of gestation. It was concluded that regular non-invasive reproductive monitoring of black rhinoceros in the wild was possible and that pregnancy could be accurately diagnosed from the measurement of 20alpha-progestagens in faecal samples. The use of this technique in wild black rhinoceros populations will offer new perspectives for in situ management of this endangered species.

20-alpha-Dihydroprogesterone↗
PubMed1997

The British Association of Head and Neck Oncologists within the wider perspectives of the USA and Europe.

An account is given of the origin and development of the British Association of Head and Neck Oncologists in relation to American and European Societies. Disillusion with the results of treatment and the poor management available for these patients before 1950, led to the formation of head and neck oncologic societies, initially in the USA, to bring about much needed improvements. Similar views were held in the UK and Western Europe which resulted in the gradual establishment of national societies in the 1960s-80s throughout Western Europe and many other countries. It is believed that these societies should continue to develop and influence medical and planning authorities for the benefit of patients diagnosed as having these uncommon, serious, but often curable tumours.

Europe↗
PubMed1993

Larynx preservation after initial non-cisplatin containing combination chemotherapy plus radiotherapy, as opposed to surgical intervention with or without radiotherapy in previously untreated advanced head and neck cancer: final analysis after 12 years follow-up.

After a median follow-up of 12 years, median overall survival of 73 patients with advanced squamous cell carcinoma of the larynx was 65 months. The 61 per cent of patients responding to two courses of initial schedule A combination chemotherapy, not including cisplatin, and the 81 per cent of patients achieving a final complete remission after definitive local therapy, had median overall survival figures of 95 and 97 months respectively. Overall survival and relapse-free survival in 51 patients treated with radiotherapy only with larynx preservation, were not significantly different from the 21 patients who completed their surgery with pre- or post-operative radiotherapy; median overall figures were 71 versus 65 months. These data add weight to our proposal that use of initial combination chemotherapy followed by radiotherapy may eliminate the need for radical surgery, so preserving the larynx in patients with advanced disease, and provides evidence of some long-term benefit with 32 per cent of this entire group surviving 12 years.

Adult↗
PubMed1993

Developmental changes in marmoset granulosa cell responsiveness to insulin-like growth factor-I: interactions with follicle-stimulating hormone and estradiol.

The biological actions of insulin-like growth factor-I (IGF-I) on granulosa cell steroidogenesis at defined stages of preovulatory follicular development in the marmoset monkey were examined. Studies were carried out by primary cell culture of granulosa cells derived from small antral (0.5-1.mm diameter) and large preovulatory (2-3.mm diameter) follicles collected during the mid-late follicular phase of the ovarian cycle. IGF-I (0.3-100 ng/ml) had no effect on progesterone accumulation or aromatase activity during 48-h culture of granulosa cells from small follicles. Progesterone accumulation by cells from large follicles was also unaffected by IGF-I over the same time period, although aromatase activity was stimulated in a dose-dependent manner (18-fold increase over basal levels with a maximally stimulatory dose of 30 ng IGF-I/ml). In contrast, granulosa cells from small and large follicles responded to IGF-I in terms of both progesterone accumulation and aromatase activity after longer periods of culture (4 days for progesterone; 6 days for aromatase). Concurrent treatment of granulosa cells from small follicles with estradiol (10(-7) M) enhanced the dose-dependent actions of IGF-I on both indices of steroidogenesis and advanced the time at which IGF-I stimulated activity was first detectable. The effects of estradiol on granulosa cell IGF-I responsiveness were independent of cell number. A synergistic action of IGF-I on FSH-stimulated granulosa cell steroidogenesis was not apparent.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Determination of ovarian cycle in Goeldi's monkey (Callimico goeldii) via the measurement of steroids and peptides in plasma and urine.

Goeldi's monkey (Callimico goeldii) is an endangered species of New World primate. The present study provides the first description of the non-conception ovarian cycle in this species based on circulating reproductive steroid and peptide hormones. The data obtained were used to validate a non-invasive system for monitoring cyclicity based on urinary reproductive steroid metabolites. Nine sexually mature females were studied. In three females, matched blood and urine samples were collected once every 2-3 days for 90-120 days; in three other females, matched blood and urine samples were collected daily for 14-20 days for one peri-ovulatory period; and in the remaining three females, urine samples only were collected once every 1-3 days for 40-60 days. Plasma progesterone, oestrone-3-conjugates and bioactive LH were measured, in addition to urinary pregnanediol-3 alpha-glucuronide and oestrone-3-conjugates. The mean maximum concentration of plasma LH occurred 1-2 days before a significant rise in plasma progesterone, which was considered to occur 1 day after ovulation. On the basis of plasma progesterone titres, the duration of the ovarian cycle was estimated as 23.9 +/- 0.4 days (n = 9), and constituted a follicular phase of 10.7 +/- 0.3 days and a luteal phase of 13.5 +/- 0.3 days. Urinary pregnanediol-3 alpha-glucuronide demonstrated a high correlation with plasma progesterone (r = 0.8), and demonstrated a significant rise at the same time as plasma progesterone.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Non-invasive monitoring of ovarian function in Asian elephants (Elephas maximus) by measurement of urinary 5 beta-pregnanetriol.

The development of an enzymeimmunoassay for 5 beta-pregnanetriol and its use for non-invasive monitoring of reproductive cycles in Asian elephants is described. Gas chromatography-mass spectrometry (GCMS) and high performance liquid chromatography (HPLC) confirmed the presence of 5 beta-pregnane-3 alpha,17 alpha,20 alpha/beta-triols as the two most abundant urinary progesterone metabolites. The assay developed used the antiserum anti-5 beta-pregnane-17 alpha,20 alpha-diol-3 alpha-gamma l glucuronide but was designed to measure the free steroid in urine samples after hydrolysis and extraction. HPLC confirmed the presence of immunoreactive pregnanetriol in urine, but indicated that the measurement was nonspecific. Immunoreactive pregnanetriol concentrations were significantly correlated with the concentrations of both progesterone (r = 0.98, n = 269, P < 0.01) and 17 alpha-hydroxyprogesterone (r = 0.95, n = 205, P < 0.01), the metabolic precursor of pregnanetriol. The mean +/- SEM deviation of cycles as determined by measurements of plasma progesterone, 17 alpha-hydroxyprogesterone and urinary pregnanetriol, respectively, were 15.54 +/- 1.5 (n = 23, where n = number of cycles), 15.21 +/- 1.7 (n = 15) and 15.45 +/- 0.94 weeks (n = 20). These results demonstrate that it is possible to monitor ovarian function in Asian elephants by the measurement of urinary immunoreactive pregnanetriol concentrations.

17-alpha-Hydroxyprogesterone↗
PubMed1992

Effects of oestradiol-17 beta on FSH-stimulated steroidogenesis in cultured marmoset granulosa cells.

A role for oestradiol in ovarian follicular development is well recognized. However, a number of disparate effects have been reported for the action of oestradiol in the primate ovary. To investigate this further, we have examined the effects of oestradiol on the differentiation of granulosa cells isolated from small (0.5-1 mm) antral follicles obtained from the ovaries of prepubertal marmoset monkeys (Callithrix jacchus). Granulosa cells were co-cultured with oestradiol and human FSH (hFSH) for 48 h, or were pretreated with oestradiol for 48 h before addition of gonadotrophin for a further 48 h. Oestradiol (0.01-100 nmol/l) had no effect on basal or hFSH-stimulated progesterone accumulation and aromatase activity when the hormones were added concurrently. Furthermore, oestradiol did not influence the ability of hFSH to induce LH/human chorionic gonadotrophin (hCG) responsiveness in immature granulosa cells. The absence of synergism between oestradiol and hFSH in the induction of marmoset granulosa cell differentiation was independent of the presence of phenol red in culture medium. However, gonadotrophin-stimulated steroidogenesis was attenuated when cells were cultured in the presence of phenol red compared with in its absence; this effect was more pronounced for gonadotrophin-stimulated aromatase activity but was evident for LH/hCG-stimulated progesterone accumulation at higher doses of hCG (10 and 100 ng/ml). An effect of phenol red on basal steroidogenesis was less obvious.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Role of partial laryngectomy after irradiation in the treatment of laryngeal cancer: a view from the United Kingdom.

This retrospective study evaluates the use of conservation surgical salvage techniques in cases of early (T1 and T2) laryngeal cancer after full-dose external irradiation. Fifty patients in one London hospital and 68 patients in another were studied for the period 1963 to 1988. Treatment policy directed that the majority of limited glottic and supraglottic tumors should be treated initially by external irradiation. The small number of glottic treatment failures had a good chance of salvage by vertical partial laryngectomy if recurrence or a new primary was detected early. Recurrence of supraglottic cancer was salvaged occasionally by horizontal partial laryngectomy if strict indications were observed. Total laryngectomy remained the final minority salvage option.

Cobalt Radioisotopes↗
PubMed1989

Fine needle aspiration cytology in the head and neck region.

Although needle aspiration diagnosis was described over 50 years ago, many patients with neck swellings are still subjected to hazardous and unnecessary open diagnostic surgical biopsy. In a six-month period, over 200 fine needle aspirates were performed on tumours from the head and neck region, 44% of which were positive for cancer. The technique of aspiration, its advantage for the patient, clinician and cytopathologist, and the results of the study will be discussed. Close cooperation between the clinician and the cytopathologist is essential.

Adolescent↗
PubMed1989

Developmental changes in luteinizing hormone/human chorionic gonadotropin steroidogenic responsiveness in marmoset granulosa cells: effects of follicle-stimulating hormone and androgens.

Factors regulating LH/hCG responsiveness in primate granulosa cells were examined in the marmoset monkey (Callithrix jacchus). Granulosa cells were isolated and pooled from small antral (0.5-1.0 mm) and large preovulatory (greater than or equal to 2 mm) follicles from mid- to late follicular phase ovaries of cyclic marmosets. The cells from small and large follicles were cultured in serum-free medium for 48 h in the absence or presence of increasing concentrations of hCG (0.1-100 ng/ml) with or without 0.1 microM androgen [testosterone or 5 alpha-dihydrotestosterone (DHT]). Granulosa cells from small follicles were also cultured in the absence or presence of a constant concentration of human FSH (30 ng/ml) with or without androgen for 48 h before exposure to hCG for an additional 48 h. Steroidogenic responsiveness was assessed by measuring progesterone accumulation in culture medium and aromatase activity in washed monolayers. Granulosa cells from large follicles showed dose-dependent increases in both progesterone accumulation and aromatase activity in response to treatment with hCG. In contrast, granulosa cells from small follicles were unresponsive to hCG. However, pretreatment of granulosa cells from small follicles for 48 h with FSH stimulated hCG responsiveness. The effects of both testosterone and DHT on hCG-stimulated aromatase activity and progesterone accumulation by granulosa cells from large preovulatory follicles were inhibitory. Testosterone and DHT also suppressed basal (no hCG) progesterone accumulation in these cells, but had no effect on basal aromatase activity. The effects of androgens on FSH-induced hCG responsiveness in immature granulosa cells were variable. The results show a development-related increase in marmoset granulosa cell responsiveness to LH/hCG and provide evidence that FSH and androgens interact to regulate the onset and expression of this critical event during preovulatory follicular development in the primate ovary.

Androgens↗
PubMed1988

Surgical salvage for squamous cancer involving the supraglottic larynx.

Anatomically the supraglottic larynx has been shown to be self contained as regards its boundaries and lymphatic compartments which tend to limit the spread of cancer arising within the region until it reaches the margins of the supraglottis (Pressman and Simon, 1961). These may be called Type A tumours. Advanced glottic tumours secondarily involving the supraglottis may be considered a sub-group within the larynx (transglottic).

Carcinoma, Squamous Cell↗
PubMed1988

A modification of the MacFee incisions for neck dissection.

The dissection of cervical lymphatics for cancer after radiotherapy imposes a special need to ensure good healing of skin flaps with good access and acceptable aesthetic results. Adaptability of incisions for extended surgery is also desirable. Although it is felt that the adoption of the basic MacFee incision pattern fulfils these criteria, the author has for years employed curved modifications of the two horizontal incision lines. This develops a waisted skin bridge which is freely mobile and gives better access to the deep structures. The technique is contrasted with other approaches and described in detail. It complies with the safe principle of join-free linear incisions and is practical for regular use.

Humans↗
PubMed1988

Induction cytotoxic chemotherapy: the significance of apparent complete clinical regression after using the Price Hill Schedule A protocol for squamous carcinoma of the head and neck.

A small group of 46 previously untreated patients out of about 260 in all who have received Price Hill Schedule A cytotoxic chemotherapy, achieved apparent complete clinical regression (ACCR) of their disease before local treatment. Forty patients were classified T3 or T4, over half having clinically positive nodes at the start of treatment. A determinate survival rate of 70 per cent disease free at three years was obtained and 74 per cent achieved quality relief of all symptoms. Two patients declined local treatment and survived three years disease free after chemotherapy alone. No recurrence has occurred to date in seven patients achieving apparent complete histological regression (ACHR) in their surgical specimens. Although ACCR does not automatically improve prognosis it is likely that it does enhance the complete remission rate, especially for those also achieving ACHR. Benefits to patients obtaining ACCR with this minimally toxic chemotherapy schedule are listed.

Adult↗
PubMed1988

Cellular aspects of pre-ovulatory folliculogenesis in primate ovaries.

According to current concepts of pre-ovulatory folliculogenesis in primate ovaries, each growing follicle has a 'threshold' requirement for stimulation by FSH which must be met if it is to enter the oestrogen-secretory phase of pre-ovulatory development. Until recently, our understanding of the intra-follicular mechanisms underlying FSH action on granulosa cells was based largely on information from non-primate laboratory animals, mainly polyovulators such as rats. The present paper describes studies on FSH-regulated granulosa cell function in relation to pre-ovulatory development in vivo and in vitro using a laboratory primate, the common marmoset (Callithrix jacchus). Measurement of aromatase activity is used as an index of granulosa cell cytodifferentiation to verify three major tenets of the 'threshold' hypothesis: (i) that granulosa cells acquire increased responsiveness to FSH and LH during pre-ovulatory growth; (ii) that these developmentally related changes are directly induced by FSH; and (iii) that intrafollicular steroids modify FSH action and thereby contribute to the establishment of follicular FSH thresholds. The results obtained highlight the value of this experimental animal model for studies of cellular and molecular aspects of pre-ovulatory folliculogenesis which are relevant to human ovaries.

Animals↗
PubMed1988

Factors influencing follicle-stimulating hormone-responsive steroidogenesis in marmoset granulosa cells: effects of androgens and the stage of follicular maturity.

Preovulatory changes in the steroidogenic function of primate granulosa cells were studied using the cyclic marmoset (Callithrix jacchus) as a model. Antral follicles (greater than or equal to 0.5 mm diameter) were dissected from mid-late follicular phase ovaries (7 days after prostaglandin-induced luteolysis) and classified by diameter as small (0.5-1.0 mm), medium (1.1-1.9 mm) or large (greater than or equal to 2.0 mm). Granulosa cells from follicles in each size category were isolated and pooled to assess steroid biosynthesis. The aromatase activity of freshly isolated granulosa cells from large follicles was 200 times greater than that of small follicles, confirming their relatively advanced preovulatory status. Granulosa cells were cultured for 48 h in the presence and absence of human (h) FSH (0.1 ng/ml), with and without 0.1 microM androgen (testosterone or 5 alpha-dihydrotestosterone), to assess basal and hormone-responsive steroidogenesis (progesterone accumulation in culture medium and aromatase activity in washed granulosa cell monolayers). Basal granulosa cell steroidogenesis increased with follicular size, and there was a development-related pattern of response to hFSH and androgen. hFSH responsiveness (maximum fold-stimulation induced by hFSH) declined with follicular size, being 2-6 times greater for granulosa cells from small vs. large follicles. On the other hand, hFSH sensitivity increased with follicular size; the dose of hFSH giving 50% of the maximum response (ED50) for cells from large follicles being 10-20 times less than that of cells from small follicles. For granulosa cells from small follicles, treatment with 0.1 microM androgen in the presence of hFSH led to dramatic (up to 16-fold) enhancement of steroidogenic responses to hFSH. In contrast, for granulosa cells from large follicles, the presence of androgen substantially inhibited aromatase activity stimulated by hFSH and had weak inhibitory effects on progesterone accumulation. These results show that granulosa cell steroidogenesis becomes increasingly sensitive to hFSH during preovulatory follicular development in marmosets. The marked ability of androgen to directly augment hFSH-responsive steroidogenesis in vitro is lost during preovulatory development, such that androgen acts in mature granulosa cells to suppress hFSH-stimulated aromatase activity. These observations are evidence of development-dependent changes in granulosa cell responses to FSH and androgens which may contribute to the control of preovulatory follicular development in primates.

Androgens↗
PubMed1987

Total glossectomy.

Total glossectomy is a procedure based on sound oncologic principles, and its usefulness may not be fully appreciated. Given the dimensions of the tongue and the need to obtain a wide margin of resection, this procedure may be indicated in selected T3 lesions and recurrences after irradiation. The procedure offers excellent palliation of pain, and form and function may be preserved by rim mandibulectomy when indicated. New reconstructive techniques allow for speedier recovery. Aspiration need not be a complication of total glossectomy if care is taken to preserve the superior laryngeal nerve. Speech rehabilitation plays an important role in returning these patients to their normal environment. Overall 1 and 3 year disease-free survival rates have been encouraging.

Adolescent↗