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S H Richards

Publications and source records attributed to S H Richards.

At least 37 records · Page 2Linked to original sources
PubMed1988

A 15 year follow-up of a controlled trial of the use of grommets in glue ear.

The long-term natural history of secretory otitis media and the changes induced in the middle ear following grommet insertion are of importance. We report the results 15 years following the unilateral insertion of a Shepard grommet and adenoidectomy for bilateral secretory otitis media. The results suggest that grommets do not protect against attic disease of late onset and induce atrophic scars which do not resolve. Grommets confer no long-term advantages to the hearing when used in the management of childhood secretory otitis media.

Acoustic Impedance Tests↗
PubMed1986

The phage SPO1-specific RNA polymerase, E.gp28, recognizes its cognate promoters in thymine-containing DNA.

The bacteriophage SPO1 gene 28-encoded protein, gp28, directs specific recognition of viral middle promoters in hydroxymethyluracil-containing DNA by the Bacillus subtilis host's RNA polymerase core. Using appropriately sensitive methods of detection, we have shown that discrimination against thymine-containing DNA is not absolute and that the gp28-containing RNA polymerase precisely initiates transcription at two thymine-containing SPO1 middle promoters.

Bacteriophages↗
PubMed1986

The preoperative and postoperative investigation of TSH and prolactin release in the management of patients with hyperprolactinaemia due to prolactinomas and nonfunctional pituitary tumours: relationship to adenoma size at surgery.

We report here our results of the pre- and post-operative assessment of prolactin and TSH status in 41 hyperprolactinaemic patients who underwent pituitary surgery over a 5 year period. Preoperatively in patients with prolactinomas (n = 33) the TSH response to domperidone decreased with increasing adenoma size. When the data are expressed on a group mean basis the exaggerated TSH response to domperidone in preoperative prolactinoma patients was reduced significantly in patients rendered normoprolactinaemic by surgery but persisted in those who remained hyperprolactinaemic. Similarly the reduced preoperative PRL responses to domperidone and TRH were significantly increased by successful surgery. In contrast patients with stalk-compression hyperprolactinaemia (n = 6) due to larger lesions which were not prolactinomas all showed reduced or absent TSH responses to domperidone. The PRL responses to domperidone and TRH were reduced or absent both in patients with prolactinomas and in those with stalk-compression hyperprolactinaemia. All patients with stalk-compression hyperprolactinaemia showed a delayed pattern of TSH response to TRH with 60 min values being greater than 20 min ones. In contrast a normal pattern of TSH response to TRH was observed in all patients with hyperprolactinaemia due to prolactinomas. Postoperatively TSH and PRL responses were largely unchanged in patients with stalk-compression hyperprolactinaemia regardless of whether normoprolactinaemia was restored by surgery. In conclusion a reduced or absent PRL response to TRH or domperidone is not diagnostic of the presence of a prolactinoma since it occurs in hyperprolactinaemic patients with prolactinomas or stalk-compression. In contrast, the TSH response to acute dopamine antagonism is exaggerated in most patients with small prolactinomas but not in those with stalk-compression hyperprolactinaemia and we have found this to be helpful diagnostically since the presence of an exaggerated TSH response to dopamine antagonism is evidence against the presence of stalk-compression hyperprolactinaemia. The observation of a delayed TSH response to TRH in a hyperprolactinaemic patient should alert the clinician to the possibility of stalk-compression hyperprolactinaemia due to a large lesion which may not be a prolactinoma.

Adenoma↗
PubMed1985

Management of selected patients with hyperprolactinaemia by partial hypophysectomy.

Results are reported in 35 patients with prolactinomas who underwent pituitary surgery within the past five years. After surgery prolactin concentrations became normal in 26 patients and symptoms were alleviated, and nine normal pregnancies were achieved in seven women, including all those who had complained of infertility. Normal prolactin concentrations were restored in 16 of 17 patients with tumours 5-19 mm in diameter but in only six of 11 with tumours less than or equal to 4 mm and four of seven with tumours greater than or equal to 20 mm. Normal prolactin concentrations were restored in all those with preoperative concentrations below 1000 mU/l but in none of those with concentrations above 10 000 mU/l. Although not all of the patients were followed up for five years, hyperprolactinaemia did not recur in any patient whose prolactin concentration had returned to normal six weeks after surgery. This included 16 patients with macroprolactinomas (greater than 10 mm in diameter), who were followed up for from two to five years. These data contrast strikingly with those reported by others at similar stages of follow up and show clearly that partial hypophysectomy offers an acceptable alternative treatment for selected patients with prolactinomas.

Adenoma↗
PubMed1985

Prolactinomas.

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Humans↗
PubMed1984

Long range base-pairing in the leftward transcription unit of bacteriophage lambda. Characterization by electron microscopy and computer-aided sequence analysis.

Restriction fragments of bacteriophage lambda DNA corresponding to the major leftward transcription unit were purified, denatured to form single-stranded DNA, self-annealed, and examined by electron microscopy. Three intrastrand stem and loop secondary structures were observed reproducibly and the locations of the paired regions were determined. A method for computer-aided sequence analysis of these regions is presented and used to identify sets of base-pairings likely to account for the observed structures. One loop observed within gene Ea47 is postulated to involve pairing of sequences which include the polypeptide initiation and termination codons. Another loop is postulated to involve pairing of sequences in gene int with sequences located in the gam-cIII region. A third loop appears to involve sequences in and to the right of gene Ea22 paired with sequences located in the bet-gam region. A general discussion of base-pairing which gives rise to long range interactions is presented along with possible effects of the postulated models on gene expression.

Bacteriophage lambda↗
PubMed1984

Sequence of the bacteriophage SP01 gene coding for transcription factor 1, a viral homologue of the bacterial type II DNA-binding proteins.

The Bacillus subtilis phage SP01, whose DNA contains 5-hydroxymethyluracil (hmUra) in place of thymine, codes for an abundant, small, basic protein called TF1. TF1 binds preferentially to hydroxymethyluracil-containing DNA and thereby selectively inhibits transcription of such DNA in vitro. The gene for TF1 has been sequenced. We find that this viral protein is a homologue of the ubiquitous bacterial type II DNA-binding proteins. The three-dimensional structure of one of these bacterial proteins has recently been determined. We are able to discern common as well as distinctive features in the amino acid sequence and the three-dimensional structure of the homologous viral protein.

Amino Acid Sequence↗
PubMed1983

Long term results of radical hypophysectomy for Cushing's disease.

Sixteen consecutive cases of Cushing's disease were treated by radical transphenoidal hypophysectomy. Surgical removal was not possible in two cases. Of the other 14, there was total clinical and biochemical remission of the disease in 13 and partial remission in one. Some form of replacement therapy has been necessary in 11 out of the 14 cases. During a long period of postoperative clinical and biochemical assessment extending over 5-14 years (average 8 years) there have been no recurrences.

17-Hydroxycorticosteroids↗
PubMed1980

Treatment of acromegaly by transethmoidal hypophysectomy.

The results of transethmoidal hypophysectomy are recorded in 34 patients with acromegaly. The post-operative growth hormone (GH) level was reduced to normal in 27 (80 per cent) and to less than 18 mu/l in 33 of the 34 cases. Two patients failed to respond clinically though in one of these the serum GH fell from 100 to 14 mu/l. Both the failures had had previous surgical interference. Amongst the responders there have been no recurrences. In view of these results we are of the opinion that transethmoidal hypophysectomy is at present the treatment of choice for acromegaly.

Acromegaly↗
PubMed1977

Acute epiglottitis in adults.

Nine cases of acute epiglottitis in adults, seen over a period of ten years, are presented. The presence of severe pain and dysphagia as universal presenting features are stressed, and the frequent absence of pharyngeal injection is noted. We found that the disease in adults differs from that in children in that pain and dysphagia are more marked, that stridor is a less prominent feature, and that Haemophilus influenzae appears not to be the sole causative organism.

Acute Disease↗
PubMed1977

Recurrent meningitis due to congenital fistula of stapedial footplate.

A case of recurrent meningitis due to a stapes footplate fistula in a child with Klippel-Fiel syndrome is reported. The relationship of deafness to this latter syndrome is noted and theories for the aetiology of the fistula discussed. A stapedectomy was performed and the oval window was obliterated using a Schuknecht fat-wire prosthesis with further packing of the middle ear with muscle.

Child↗