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P Austin

Publications and source records attributed to P Austin.

At least 37 records · Page 2Linked to original sources
PubMed1998

A novel assay for the distribution of pyrithione biocides in bacterial cells.

Sodium pyrithione and zinc pyrithione (NaPT and ZnPT, respectively) are widely used as cosmetic preservatives and metal chelating agents. They are commonly assayed using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). However, a simple quantitative colorimetric assay has not been previously reported for these compounds. This paper describes the development of a spectrophotometric assay for the quantification of the pyrithiones which is based on the chelation of copper (II) ions by the biocides. This assay was developed in order to facilitate the determination of the distribution of these biocides in the Gram-negative bacteria Escherichia coli NCIMB 10,000 and Pseudomonas aeruginosa NCIMB 10,548. Sodium pyrithione was exhibited only in the cytosol of E. coli and Ps. aeruginosa. Zinc pyrithione, however, was assayed in the cytosol of both bacteria and was found in the cell envelope of Ps. aeruginosa. These findings suggest that the pyrithione biocides are active within bacterial cells as well as at the cell membrane.

Anti-Infective Agents, Local↗
PubMed1997

The failed anti-incontinence mechanism: a flap valve or cecal wrap for surgical reconstruction.

PURPOSE: On a long-term basis patients with continent urinary diversions may have an acceptable number of complications, such as urinary incontinence. We report on a new surgical technique for treatment of the incompetent anti-incontinence segment. MATERIALS AND METHODS: Seven patients presented with a large capacity, low pressure reservoir and an incompetent anti-incontinence mechanism. The original anti-incontinence mechanism consisted of an intussuscepted reimplanted appendix (Mitrofanoff) in 2 patients, tapered ileum and reinforced ileocecal valve in 3, and tapered and reimplanted ileal segment in 2. Surgical reconstruction involved 2 stages: stage 1 - lengthening and tubularizing the cecum with the anti-incontinence segment and stage 2 - creation of the flap valve mechanism. Stage 2 required intraoperative modification when abundant peri-reservoir fibrosis, a thin-walled reservoir (cecal wrap) or an excessive thickened mesentery was encountered. RESULTS: After a mean followup of 7 months 6 of 7 patients performed catheterization every 4 hours and were continent. Several patients required a concomitant procedure with the incontinence revision. CONCLUSIONS: We describe a 2-stage technique for correction of a variety of untoward anatomical conditions related to a failed anti-incontinence segment with continent urinary reservoirs. Concomitant repair of other coexisting structural abnormalities related to the continent reservoir may also be necessary.

Adult↗
PubMed1997

Evaluation and management of parastomal hernia in association with continent urinary diversion.

PURPOSE: We discuss the incidence and diagnosis of parastomal hernias in association with continent urinary reservoirs. We also present a surgical technique appropriate for correction of this complication. MATERIALS AND METHODS: We evaluated 21 patients with parastomal hernia after construction of a continent urinary reservoir. The hernia developed secondary to diversion with an ileocecal segment in 19 patients and a Kock procedure in 2. Subsequent to development of the parastomal hernia 13 patients (61.9%) had simultaneous urinary incontinence, 2 (9.5%) had difficulty catheterizing the reservoir and 4 (19.047%) had associated pain over the stomal area. Evaluation was primarily by physical examination. However, 2 patients (9.5%) required abdominal computerized tomography to confirm the diagnosis of parastomal hernia. Surgical repair was recommended for all patients, and 19 underwent repair with or without revision of the anti-incontinence segment. Reconstruction included transabdominal takedown of the anti-incontinence segment from the abdominal wall with parastomal hernia closure through a midline incision, external reinforcement of the hernia opening with Marlex mesh when the diameter exceeded 6 cm., revision of the anti-incontinence mechanism when simultaneous urinary incontinence existed preoperatively and repositioning of the stoma site through a new selected area in the abdominal wall. RESULTS: The success rate (mean followup 23.4 months) with this surgical approach was 89.5%. Incontinence due to failure of the anti-incontinence mechanism was successfully corrected in 13 patients (100%). CONCLUSIONS: Long-term followup of continent urinary reservoirs is often associated with development of parastomal hernia. This complication can be associated with urinary incontinence, peristomal pain and difficult catheterization. Evaluation is primarily by physical examination but selected clinical situations require abdominal computerized tomography to confirm the diagnosis. The surgical technique following the steps described has been associated with minimal morbidity and has provided excellent surgical results (89.5% success rate).

Adult↗
PubMed1996

Urethral obstruction after anti-incontinence surgery in women: evaluation, methodology, and surgical results.

OBJECTIVES: To evaluate a group of women with voiding dysfunction and a low maximum flow rate (MFR) (less than or equal to 12 mL/s) after surgery for stress urinary incontinence (SUI); to establish diagnostic parameters indicating obstruction in an attempt to determine treatment selection; and to evaluate preliminary surgical results. METHODS: Eighteen women who underwent anti-incontinence surgery for SUI were diagnosed as having infravesical obstruction (IO). Thirteen women (group A [72%]) presented with clinically predominant symptoms of urgency, frequency, intermittency, and a variable vesical residual volume (RV), and five (group B [28%]) had as their most significant symptoms a high vesical RV and urinary tract infection that had been managed with intermittent catheterization (IC). The diagnosis of IO, suspected after clinical history, was established after physical examination and cystoscopic, cystographic and urodynamic investigations. RESULTS: Bladder instability was demonstrated in 6 group A patients (46%) and 1 group B patient (20%) (P = NS). Mean MFRs were 8.07 and 7.2 mL/s, respectively, in both groups (P = NS). Mean maximal voiding pressures (MVPs) were 20.23 and 5 cm H20, and mean RVs were 57.46 and 174 mL, respectively; both differences were statistically very significant (P <0.01 and P <0.001, respectively). High to normal MVPs occurred in 2 patients overall (11%). Bladder neck overcorrection, midurethral distortion, and postsurgical cystocele were demonstrated in both groups in 11 (85%), 0, and 2 (15%) patients in group A and 3 (60%), 2 (40%), and 3 (60%) patients in group B, respectively (P = NS). Patients in group A were treated surgically with cystourethrolysis and a repeated, less obstructive anti-incontinence operation. In group B 2 women (40%) had a similar surgical procedure; 1 (20%) underwent isolated urethrolysis; and 2 (40%) are currently maintained with IC. CONCLUSIONS: Among these 18 patients with voiding dysfunction after anti-incontinence surgery, a primary diagnosis of IO was established clinically. Only patients with a low MFR were selected for this study. Cytographic and endoscopic investigation as well as the presence of postsurgical cystocele assisted in establishing the diagnosis. The success rate with urethrolysis and resuspension was 60% for the 13 women with predominantly urgency, frequency, and the highest MVPs (20.23 +/- 9.67 cm H20 [group A) and 33% for the 5 women with urinary retention presenting the lowest MVPs (5.00 +/- 7.07 cm H20 [group A]) and 33% for the 5 women with urinary retention presenting the lowest MVPs (5.00 +/- 7.07 cm H20 [group B]). An added resuspension procedure is probably unnecessary in the latter group of patients and requires careful individual selection in the former group.

Adult↗
PubMed1994

Development and evaluation of an inventory for rating client satisfaction with outcome in HIV counseling: the Albion Center scale.

We developed an inventory for rating client satisfaction with outcome in HIV counseling, based on interview responses with clients. The resulting 19-item scale was subject to factor analysis and four factors, accounting for 56% of the variance, emerged. The factors described dimensions of Perception of progress and improved mood; Recognition of a specific need for counseling; Behavior change from counseling; and Counseling climate. Factor-scored scales were significantly associated with time in counseling and for the Specific need for counseling scale, HIV-seropositive respondents had a significantly higher score. Scale reliabilities (Cronbach's alpha) were between 0.85 and 0.50. Concurrent administration with the Counseling Evaluation Inventory indicated that there were significant correlations between the two scales.

Adult↗
PubMed1992

Temporary iridium-192 implant in the management of carcinoma of the prostate.

The controversy about the treatment of carcinoma of the prostate has increased in the last decade, with most urologists favoring radical prostatectomy rather than primary irradiation. Several reports of persistent tumors in 50% to 90% of patients after external irradiation and permanent iodine-125 implantation of the prostate have been disturbing. From July 1977 to December 1985, 200 patients with adenocarcinoma of the prostate were treated by combining bilateral pelvic lymphadenectomy and temporary interstitial iridium-192 implantation of the prostate, followed by external irradiation. Seventy-four (36%) patients underwent biopsies of the prostate 4 months to 2 years after completion of the irradiation. Only 12 (16%) patients had persistent tumors. Complications were minimized subsequently by dose modifications.

Adenocarcinoma↗
PubMed1990

Growth inhibitory and biocidal activity of some isothiazolone biocides.

Similar patterns of growth inhibition were observed for the three biocides, benzisothiazol-3-one (BIT), 5-chloro-N-methylisothiazol-3-one (CMIT) and N-methylisothiazol-3-one (MIT) against Escherichia coli ATCC 8739 and Schizosaccharomyces pombe NCYC 1354. After periods of induced stasis, proportional to biocide concentration, growth proceeded at an inhibited rate. Extrapolation of the static periods and inhibited growth rates against biocide concentration gave minimum growth inhibitory concentration estimates of 0.1-0.5 micrograms/ml for CMIT, 15-20 micrograms/ml for BIT and 40-250 micrograms/ml for MIT. Patterns of growth inhibition by CMIT and induced morphological changes in inhibited cultures suggested this compound to also inhibit initiation of DNA replication. Growth inhibitory activity was rapidly quenched by the addition of thiol-containing materials such as glutathione and cysteine. The activity of CMIT was additionally quenched by the presence of the non-thiol amino acids valine and/or histidine. These results suggest that the chlorinated isothiazolones can react with amines as well as with essential thiol groups.

DNA Replication↗
PubMed1990

Chemical reactivity of some isothiazolone biocides.

Chemical reactions between the isothiazolone biocides, N-methylisothiazol-3-one (MIT), benzisothiazol-3-one (BIT) and 5-chloro-N-methylisothiazol-3-one (CMIT) with cysteine have been investigated by u.v. and NMR spectroscopy. At physiological pH all three agents interacted oxidatively with thiols to form disulphides. Further interaction with thiols caused the release of cystine and formation of a reduced, ring-opened form of the biocide (mercaptoacrylamide). In an analogous fashion to the initial reaction the mercaptoacrylamide reacted with another molecule of biocide to give biocide dimers. NMR spectral studies indicated that for CMIT the mercaptoacrylamide form is capable of tautomerization to a highly reactive thio-acyl chloride. Formation of mercaptoacrylamide was in all cases highly pH-dependent. Alcohol dehydrogenase was insensitive to all three agents but was highly sensitive to CMIT when co-administered with dithiothreitol. Capacity to form a thioacyl chloride from the mercaptoacrylamide is suggested to account for much of this enhanced activity. Stopped-flow spectroscopic studies showed rates of reaction with glutathione (GSH) to directly parallel antimicrobial activity. Additionally, CMIT was able to react directly with both ionization states of GSH (pH 7-10) whilst BIT and MIT appeared only to interact when the glutamyl-nitrogen of GSH was charged (pH 8.5).

Alcohol Dehydrogenase↗
PubMed1986

Monoclonal antibodies to HLA-DP-transfected mouse L cells.

Mouse L cells transfected with human HLA-DP (DPw4) alpha and beta genes were used to make monoclonal antibodies in C3H mice. A polymorphic antibody, DP11.1, was obtained, as well as several monomorphic antibodies. In ELISAs, DP11.1 bound to DPw4 cells and, more weakly, to DPw2, but not DPw1, -3, -5, or -6, using HLA homozygous cells. It also bound to L-cell transfectants expressing either DPw2 or DPw4 products. From B lymphoblastoid cell lysates labeled with [35S]methionine, the antibody immunoprecipitated alpha and beta chains of a similar size to those precipitated by a well-characterized DP monoclonal antibody, B7/21.2. Immunoblotting indicated that the DP11.1 antibody was directed against the alpha chain. This result confirms partial sequence data that showed that the DP alpha chain, as well as DP beta, is polymorphic, and that DPw2 and -4 alpha chains are very similar, if not identical.

Animals↗
PubMed1984

Linkage map of two HLA-SB beta and two HLA-SB alpha-related genes: an intron in one of the SB beta genes contains a processed pseudogene.

Three overlapping cosmid clones contain coding sequences for four HLA Class II genes, provisionally identified as two HLA-SB alpha and two HLA-SB beta genes. The genes are in the order beta, alpha, beta, alpha, inverted with respect to each other. One of the SB beta genes contains a 513 bp sequence that appears to be a processed pseudogene, flanked by direct 17 bp repeat sequences, in the intron upstream of the beta 1 exon. The pseudogene is homologous to a family of sequences of approximately 25-40 members, most of which are not on chromosome 6. A cDNA clone, highly homologous to the pseudogene, except for its 5' end, contains a normal poly(A) addition site and a poly(A) tail. The cDNA clone is homologous to a single-copy gene in both man and mouse, encoded on human chromosome 15. A search of published DNA sequences identified a mouse sequence, with about 77% similarity to the pseudogene sequence, in the negative strand of an intron in a mouse dihydrofolate reductase gene. The second SB beta gene does not contain the pseudogene sequence.

Amino Acid Sequence↗
PubMed1983

Elastofibroma oculi.

A 69-year-old woman had a placoid lesion extending from the temporal limbus with a ptyergioid head to involve extensively the temporal epibulbar conjunctiva, the superolateral and inferolateral fornices, and the lateral canthus. It was composed of thickened bundles of collagen, scattered islands of adipose tissue, and abundant refractile linear elastinophilic structures. Electron microscopy confirmed that the elastinophilic structures were mature elastic fibers embedded within markedly thickened bundles of collagen. This lesion resembles elastofibromas that occur in a subscapular location. Elastofibroma oculi is distinguishable from the more common pterygium and pinguecula by the sparing of the immediate subepithelial zone of the conjunctiva, which is preferentially involved by these other lesions, and by failure to exhibit ultrastructurally microfibrillar aggregates and dystrophic elastic fibers. Both the elastic fibers and thickened bundles of collagen in the elastofibroma are presumed to have arisen from activated fibroblasts.

Aged↗
PubMed1983

Primary infiltrating signet ring carcinoma of the eyelids.

A 61-year old man presented with a five-year history of a swelling initially developing in his right lower lid that progressed to involve the lateral canthal skin and eventually the upper lid and anterior orbit. He was discovered to have an infiltrating, poorly differentiated, mucin-producing carcinoma. Systemic work-up failed to disclose a visceral malignancy, and it was concluded that his tumor was primary in the lids, arising from an adnexal sweat gland. Three other reports in the literature also share almost identical clinical and pathologic features, in that all of the earlier reports dealt with middle-aged or elderly men who had diffusely indurated lids. Histopathologically, the tumor cells grow diffusely in a sclerotic stroma, and resemble the "histiocytoid" variant of metastatic breast carcinoma to the lids in women. Ultrastructural studies in our case point toward an apocrine origin, although earlier authors have favored an eccrine origin. Despite its indolent clinical course, the tumor is capable of producing regional and distant metastases on long-term follow-up. Complete local excision, possibly necessitating radical surgery, is probably the preferred method of treatment, but local radiotherapy may have a beneficial effect in retarding spread of the disease.

Adenocarcinoma, Mucinous↗