Search PubMed⌕ Search

Biomedical subjects

C S Cooper

Publications and source records attributed to C S Cooper.

At least 55 records · Page 3Linked to original sources

Prognostic factors for long-term renal function in boys with the prune-belly syndrome.

PURPOSE: Renal failure develops in 25 to 30% of patients with the prune-belly syndrome. The clinical parameters associated with renal failure in this condition are not well understood. We determined which factors predict renal failure in children with the prune-belly syndrome. MATERIALS AND METHODS: We reviewed the records of 35 patients with the prune-belly syndrome who were treated at our hospital during a 37-year period. Nadir serum creatinine, time to nadir creatinine, presence or absence of a patent urachus, presence and severity of urinary tract infection, and renal failure were analyzed. RESULTS: Mean followup was 14 years 2 months. In 2 of the 17 patients with a nadir serum creatinine of less than 0.7 mg./dl. renal failure developed. Each of these 2 children also had clinical pyelonephritis and urosepsis. In 12 of the 13 patients nadir serum creatinine greater than 0.7 mg./dl. strongly predicted renal failure. Nonfebrile urinary tract infection within the first year of life was not predictive of outcome (p = 0.8) but a history of clinical pyelonephritis correlated with eventual renal failure (p<0.001). Urosepsis also correlated with renal failure (p = 0.008). Children with at least 1 normal kidney on renal ultrasound or renal scan had a significantly lower chance of renal failure (p<0.001). CONCLUSIONS: Bilaterally abnormal kidneys on ultrasound or renal scan, a nadir serum creatinine of greater than 0.7 mg./dl. and clinical pyelonephritis are prognostic for renal failure.

Adolescent↗

Identification of single amino acids in the human papillomavirus 11 E2 protein critical for the transactivation or replication functions.

The papillomavirus E2 protein is required for viral transcriptional regulation and replication. The E2 protein has a modular structure with two highly conserved domains, a sequence-specific DNA-binding and dimerization domain and a conserved N-terminus which is important for transcriptional transactivation, replication, and interaction with the E1 protein to determine which specific amino acids or regions in the N-terminus were important for the replication or transactivation functions. Single amino acid substitutions were created at highly conserved, highly charged amino acids in the HPV 11 E2 N-terminus. Each amino acid was mutated to a nonpolar alanine residue or a similarly charged amino acid. The mutated E2 proteins were analyzed for their abilities to support transcriptional transactivation and transient DNA replication and to enhance binding of E1 to the origin of replication. Single amino acid substitutions were identified which were defective for either the replication or transactivation functions, which demonstrated that the replication and transactivation functions within the N-terminus are separable. In several cases different amino acid substitutions at the same site had variable effects on transcription or replication, highlighting the importance of hydrophobic interactions or side chain structure at each site. The replication function appeared to correlate with the ability of E2 to enhance binding of E1 to the origin of replication though these studies also suggest that other functions performed by the E2 protein may be important for replication.

Alanine↗

Effect of exogenous testosterone on prostate volume, serum and semen prostate specific antigen levels in healthy young men.

PURPOSE: We investigate and define the effects of exogenous testosterone on the normal prostate. MATERIALS AND METHODS: A total of 31 healthy volunteers 21 to 39 years old were randomized to receive either 100, 250 or 500 mg. testosterone via intramuscular injection once a week for 15 weeks. Baseline measurements of serum testosterone, free testosterone and prostate specific antigen (PSA) were taken at week 1. Semen samples were also collected for PSA content and prostate volumes were determined by transrectal ultrasound before testosterone injection. Blood was then drawn every other week before each testosterone injection for the 15 weeks, every other week thereafter until week 28 and again at week 40. After the first 15 weeks semen samples were again collected, and prostate volumes were determined by repeat transrectal ultrasound. RESULTS: Free and total serum testosterone levels increased significantly in the 250 and 500 mg. dose groups. No significant change occurred in the prostate volume or serum PSA levels at any dose of exogenous testosterone. Total semen PSA levels decreased following administration of testosterone but did not reach statistical significance. CONCLUSIONS: Despite significant elevations in serum total and free testosterone, healthy young men do not demonstrate increased serum or semen PSA levels, or increased prostate volume in response to exogenous testosterone injections.

Adult↗

Relationship of chronic endurance exercise to the somatotropic and sex hormone status of older men.

To investigate putative abrogating effects of habitual endurance exercise on age-related changes in endocrine function and body composition, we compared insulin-like growth factor-I (IGF-I), sex hormonal status and body composition in 15 Masters runners and 15 minimally exercising men (MEM) aged 60-70 years. A higher maximal oxygen uptake (VO2 max.) in the runners (41.4+/-1.6 compared with 27.3+/-1.4 ml/kg/min, P=0.0001; mean+/-S.E.M.) reflected our group allocations. Analysis of body composition and bone mineral density (BMD) by dual energy X-ray absorptiometry showed no group differences in lean tissue mass or in regional or whole body BMD, but MEM were heavier, reflecting greater adiposity. Of nine muscle groups tested, only quadriceps strength differed significantly, being greater in runners (60.3+/-2.8 compared with 51.1+/-2.3 kg, P=0.02). Total IGF-I (129+/-10 compared with 124+/-11 ng/ml, P=0.72) and IGF-binding protein-3 (2854+/-94 compared with 2623+/-128ng/ml, P=0.16), were similarly depressed compared with young adult norms in both groups. There was no relationship between total or bioavailable IGF-I and any body composition, BMD or muscle strength variable. In the runners, concentrations of total testosterone (19.1+/-0.8 compared with 15.0+/-0.9 nmol/l, P=0.002) and sex hormone binding globulin (SHBG) (124.4+/-21.6 compared with 67.7+/-11.6 nmol/l, P=0.03) were significantly greater, but the free androgen index was significantly lower (20.7+/-2.7 compared with 31.4+/-4.1, P=0.04). Directly measured free testosterone, however, was similar between the runners and MEM (47.9+/-1.8 compared with 47.1+/-2.0 nmol/l P=0.80). Therefore the group differences in total testosterone and free androgen index were due to their different SHBG concentrations. Although estrone concentration was higher in MEM (85.1+/-5.2 compared with 108+/-6.7 pmol/l, P=0.03), estradiol concentration was similar between groups (73.0+/-6.3 compared with 81.8+/-8.0 pmol/l, P=0.18), indicating that estrogens were not responsible for the increased SHBG in runners. These results indicate that even high levels of regular endurance exercise do not prevent the decline in the somatotropic axis that occurs with aging. Furthermore, the somatic effects of exercise in older men (reduced adiposity and increased regional muscle strength) occurred independently of somatotropic or androgen status. Although habitual exercise does not influence free testosterone concentrations in older men, it appears to enhance the age-associated increase in SHBG synthesis.

Aged↗

The Heidelberg classification of renal cell tumours.

This paper presents the conclusions of a workshop entitled 'Impact of Molecular Genetics on the Classification of Renal Cell Tumours', which was held in Heidelberg in October 1996. The focus on 'renal cell tumours' excludes any discussion of Wilms' tumour and its variants, or of tumours metastatic to the kidneys. The proposed classification subdivides renal cell tumours into benign and malignant parenchymal neoplasms and, where possible, limits each subcategory to the most commonly documented genetic abnormalities. Benign tumours are subclassified into metanephric adenoma and adenofibroma, papillary renal cell adenoma, and renal oncocytoma. Malignant tumours are subclassified into common or conventional renal cell carcinoma; papillary renal cell carcinoma; chromophobe renal cell carcinoma; collecting duct carcinoma, with medullary carcinoma of the kidney; and renal cell carcinoma, unclassified. This classification is based on current genetic knowledge, correlates with recognizable histological findings, and is applicable to routine diagnostic practice.

Humans↗

Fusion of splicing factor genes PSF and NonO (p54nrb) to the TFE3 gene in papillary renal cell carcinoma.

We demonstrate that the cytogenetically defined translocation t(X;1)(p11.2;p34) observed in papillary renal cell carcinomas results in the fusion of the splicing factor gene PSF located at 1p34 to the TFE3 helix-loop-helix transcription factor gene at Xp11.2. In addition we define an X chromosome inversion inv(X)(p11.2;q12) that results in the fusion of the NonO (p54nrb) gene to TFE3. NonO (p54nrb), the human homologue of the Drosophila gene NonAdiss which controls the male courtship song, is closely related to PSF and also believed to be involved in RNA splicing. In each case the rearrangement results in the fusion of almost the entire splicing factor protein to the TFE3 DNA-binding domain. These observations suggest the possibility of intriguing links between the processes of RNA splicing, DNA transcription and oncogenesis.

Adolescent↗

Laparoscopic nephrectomy of a horseshoe kidney.

The role of laparoscopic surgery in the treatment of benign renal diseases continues to evolve with the development of equipment and refinement of techniques. A minimally invasive approach to the treatment of these lesions offers several advantages, including shorter convalescence. We describe the first laparoscopic nephrectomy involving a horseshoe kidney.

Adult↗

Hip and knee replacement as a relative contraindication to laparoscopic pelvic lymph node dissection.

PURPOSE: We investigated the effect of lower extremity joint prostheses on subsequent laparoscopic pelvic lymph node dissection. MATERIALS AND METHODS: We reviewed the records and pathology studies of 5 patients who underwent laparoscopic pelvic lymph node dissection subsequent to total hip or knee replacement from 1990 through 1995. RESULTS: Four of the 5 laparoscopic operations were complicated, 3 were unsuccessful in obtaining bilateral pelvic lymph nodes and 2 required conversion to an open procedure. Examination of the lymph nodes revealed sinus histiocytosis in the 4 cases in which nodal tissue was removed. CONCLUSIONS: The increased risk of complications in certain patients with lower extremity joint prostheses may contraindicate attempted laparoscopic pelvic lymph node dissection.

Aged↗

Synthesis and structure-activity relationships of 2-pyridones: a novel series of potent DNA gyrase inhibitors as antibacterial agents.

Two novel series of 2-pyridones were synthesized by transposition of the nitrogen of 4-quinolones to the bridgehead position. This subtle interchange of the nitrogen atom with a carbon atom yielded two novel heterocyclic nuclei, pyrido[1,2-alpha]pyrimidine and quinolizine, which had not previously been evaluated as antibacterial agents and were found to be potent inhibitors of DNA gyrase. Quinolizines with a methyl group at the 9-position such as (S)-45a (ABT-719) demonstrate exceptional broad spectrum antibacterial activity. Most notably, they are active against resistant bacteria such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant strains of enterococci, and ciprofloxacin-resistant organisms. In addition, 2-pyridones also possess favorable physiochemical and pharmacokinetic properties. These 2-pyridones were synthesized from the commercially available starting materials by 10-17 linear transformations. The structure of an adduct yielded by this sequence, (S)-45a (ABT-719), was determined by X-ray crystallographic analysis.

Animals↗

Fusion of the EWS gene to CHN, a member of the steroid/thyroid receptor gene superfamily, in a human myxoid chondrosarcoma.

The specific chromosomal translocation t(9;22)(q22-31;q11-12) has been observed in the myxoid variant of human chondrosarcoma. In agreement with this observation we report that the EWS gene located at chromosome band 22q12 becomes fused to CHN, a member of the steroid/thyroid receptor gene superfamily located at 9q22-31, in a skeletal myxoid chondrosarcoma. CHN appears to be the human homologue of the rat gene NOR1, which was recently identified as a sequence overexpressed in rat brain cells undergoing apoptosis. Our results also indicate that the chimaeric EWS-CHN gene encodes a EWS-CHN fusion protein in which the C-terminal RNA-binding domain of EWS is replaced by the entire CHN protein, comprising a long N-terminal domain, a central DNA binding domain and a C-terminal ligand-binding/dimerisation domain.

Amino Acid Sequence↗