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Biomedical subjects

D J Jones

Publications and source records attributed to D J Jones.

At least 91 records · Page 5Linked to original sources
PubMed1991

Percutaneous nephrolithotomy and the solitary kidney.

We reviewed 53 patients with stones in a solitary kidney who had undergone percutaneous nephrolithotomy. Previous surgery on that kidney had been performed in 35.8%, and 50.9% had other medical conditions including 26.4% who had impaired renal function. Staghorn or partial staghorn calculi were present in 52.9% and an additional 18.8% had multiple stones. Postoperative complications in 18.8% of the patients included sepsis, the need for transfusion and 1 death of bronchopneumonia. Percutaneous nephrolithotomy alone resulted in a 77.3% rate free of stone or fragments of 2 mm, or less. This rate increased to 86.8% with the addition of extracorporeal shock wave lithotripsy, ureteroscopy or open surgery (2 patients). Only 1 patient suffered long-term deterioration in renal function. Percutaneous nephrolithotomy is a safe procedure in the solitary kidney. It should be considered in those patients with complex stone burdens and impaired renal function when reduction in stone bulk and improved renal function may allow other treatment modalities to be used.

Female↗
PubMed1991

Percutaneous nephrolithotomy for calculi in horseshoe kidneys.

Between 1983 and 1988, 15 patients (18 kidneys) underwent percutaneous nephrolithotomy at this unit for calculi in horseshoe kidneys. A standard 1-stage percutaneous access technique with minor modifications was used. In situ disintegration with ultrasound or electrohydraulic lithotripsy was necessary in 15 moieties (83.3%) and nephrostomy drainage was required in 12 (66.7%). Percutaneous access was not a problem and there were minimal perioperative problems. Blood transfusion was required postoperatively in 2 patients. A total of 14 kidneys (77.8%) were rendered free of stone with percutaneous nephrolithotomy alone and 2 kidneys were left with asymptomatic stone fragments of 2 mm. or less. Another 2 kidneys became free of stone after extracorporeal shock wave lithotripsy, thus giving an over-all stone clearance rate of 88.8%. We conclude that percutaneous nephrolithotomy is an acceptable treatment for stones in horseshoe kidneys and it is the treatment of choice for patients in whom imaging is difficult or impossible.

Adult↗
PubMed1991

Haemospermia: a prospective study.

A prospective study of 74 men with haemospermia is presented. Most (76%) had experienced 1 or 2 episodes only and 9 (12%) were over 40 years old. Simple investigations led to a diagnosis in all 9 of these men and of those under 40, no pathology could be detected in 48%. A diagnosis was made in 32 of the remaining 34 men by simple investigations. In patients over 40 years of age with haemospermia, a potentially treatable cause will normally be found by routine investigation which should include cystoscopy. In younger men, non-invasive investigation alone should identify any pathology. Invasive investigations should be reserved for those patients in whom the problem is prolonged, excessive or in association with other symptoms.

Adult↗
PubMed1991

The effect of ractopamine hydrochloride on the carcass cutting yields of finishing swine.

This study was designed to evaluate growth performance, carcass cutting yield, and processing characteristics of boneless hams and bellies from finishing pigs fed diets containing 0, 5, 10, or 20 ppm of the phenethanolamine ractopamine hydrochloride (RAC). Sixty pigs were blocked by starting weight and randomly assigned to pens (four pigs/pen) within each of three blocks. Treatments were then randomly assigned to the pens to total six pens of the 0-ppm level and three pens each at the 5-, 10-, and 20-ppm RAC levels. Weight gain and feed consumption were monitored and animals were slaughtered by weight block after approximately 48 d on trial. Slaughter weight, ADG, and feed/gain were improved (P less than .05) for RAC treatments. Dressing percentage was higher and increased linearly (P less than .05) for RAC treatments. Carcass weight, length, leaf fat weight, backfat thickness, loin eye area, and color, marbling, and firmness of the longissimus were evaluated. The RAC-treated carcasses were heavier (P less than .05) and loin eye area increased linearly (P less than .05). One side of each carcass was fabricated using National Association of Meat Purveyors specifications. Trimmed hams and loins from the RAC treatments were heavier (P less than .05) than those from control animals. No differences (P greater than .05) in carcass cutting yield (percentage of trimmed primal cuts) were observed between treatments. However, trimmed hams and loins from the 20-ppm RAC treatment represented a greater (P less than .05) percentage of carcass weight than did those from control animals. Ractopamine did not affect raw belly or bacon characteristics (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1990

Modulation of [3H]serotonin release by dihydropyridines in spinal cord synaptosomes.

The release of [3H]monoamines from preloaded synaptosomes from spinal cord is K(+)-dependent and can be modulated by L-type Ca2+ channel agonists such as the 1,4-dihydropyridine (1,4-DHP), Bay K 8644. Whereas the basal release of [3H]monoamines was not altered by Bay K 8644, K(+)-stimulated release of [3H]norepinephrine was enhanced 35% and [3H]serotonin 50%. Modulation of release by Bay K 8644 was dependent on the K+ concentration in the medium, being present only at submaximal depolarization with 15 mM K+. Enhanced release in the presence of Bay K 8644 was concentration-dependent and Ca2(+)-dependent. Ca2(+)-independent release induced by fenfluramine was not enhanced by Bay K 8644. Both nimodipine and nitrendipine, 1,4-DHP antagonists, produced a concentration-dependent block of the Bay K 8644-induced monoamine release and had no independent effect on basal or K(+)-stimulated release. omega-Conotoxin GVIA (omega-CgTx) produced a concentration dependent decrease of K(+)-stimulated serotonin release, which antagonized the stimulatory effect of low concentrations of Bay K 8644. However, omega-CgTx did not alter the enhancement of K(+)-stimulated release at higher concentrations of Bay K 8644. The data from the present work establish the conditions for modulation of K(+)-evoked monoamine release in spinal cord by 1,4-DHP agonists and suggest a role for the L-type voltage dependent Ca2+ channel in this process.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1990

The changing practice of percutaneous stone surgery. Review of 1000 cases 1981-1988.

A review was carried out on 1000 cases of percutaneous nephrolithotomy (PCNL), Group 1 (500), 1981-1985, being compared with Group 2 (500), 1985-1988. Previous renal surgery had been performed in 17.4% of patients in Group 1 and 36% in Group 2. There were 17.2% complicated patients in Group 1 and 51% in Group 2. The stone burden included 30.2% multiple, partial staghorn and staghorn calculi in Group 1 and 47.2% in Group 2. The use of in situ stone disintegration increased from 22.2% in Group 1 to 73.4% in Group 2 and nephrostomy drainage was necessary in 29.6% compared with 75%. Post-operative complications increased from 13.6 to 24%. Stone-free rates decreased from 92 to 51%, but the addition of other methods of treatment and the inclusion of patients with stone fragments of 2 mm or less increased these figures to 98% in Group 1 and 83% in Group 2. More complicated patients with complex stones are now being referred for PCNL. These patients require multiple treatments, including extracorporeal shock wave lithotripsy (ESWL) and percutaneous surgery, in combination with other endoscopic and radiological procedures.

Adolescent↗
PubMed1990

The effect of various levels of ractopamine hydrochloride on the performance and carcass characteristics of finishing swine.

Six trials involving 888 pigs (Study 1) and three trials involving 360 pigs (Study 2) were conducted at various geographical locations in the U.S. and Canada to evaluate the effect of ractopamine hydrochloride on the performance and carcass characteristics of finishing swine. All trials were conducted using a randomized complete block design. Trial data were pooled within study for statistical analysis. Pigs averaged approximately 64.5 kg (Study 1) and 65.9 kg (Study 2) initially and had ad libitum access to a 16% crude protein corn-soybean meal or barley-soybean meal diet. Ractopamine was included in the diet at 0, 2.5, 5, 10, 20 or 30 ppm (Study 1), or at 0, 5, 10, 15 or 20 ppm (Study 2); diets were fed for an average of 45 d (Study 1) and 50 d (Study 2) to a final weight of about 104.3 kg (Study 1) and 106.6 kg (Study 2). Carcass dissection data were collected in three of the six trials in Study 1 (0, 5 and 20 ppm ractopamine) and in all three trials in Study 2 (0, 5, 10, 15 and 20 ppm ractopamine). All ractopamine levels improved (P less than .05) ADG and feed: gain (Studies 1 and 2) above those of control pigs. Ractopamine levels of 10 to 30 ppm (Studies 1 and 2) improved (P less than .05) dressing percentage over controls. Pigs fed ractopamine at 5 and 20 ppm (Study 1) and 10, 15 and 20 ppm (Study 2) had increased (P less than .05) dissected leanness compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1990

A comparison of danazol and placebo in the treatment of adult idiopathic gynaecomastia: results of a prospective study in 55 patients.

In an attempt to define the efficacy of danazol in the treatment of idiopathic gynaecomastia, 55 patients were enrolled into a randomised double-blind comparison of danazol 200 mg twice daily for 3 months against placebo. The results of 52 patients were evaluated, three patients being excluded because of protocol violations. Danazol improved breast tenderness to a significantly greater degree than did placebo (P = 0.022, danazol vs placebo) and was associated with statistically significant improvement in the degree of gynaecomastia and in its measured size (P less than 0.05). The intended management of patients who had received danazol was less likely to be surgery compared to the placebo group when assessed at the end of treatment (27% vs 50%). Minor side effects were common in both groups, but significant weight gain was noted in the danazol group alone. If there is no urgent need for rapid resolution of gynaecomastia, danazol 200 mg twice daily can provide effective control of symptoms and may obviate the need for surgery.

Adolescent↗
PubMed1989

Twenty-four hour variation of alpha 1-adrenergic receptors in the pineal gland of the male Syrian hamster.

Specific binding of [125I]iodo-[beta-(4-hydroxyphenyl)-ethylaminomethyl]tetralone ([ 125I]HEAT) was used to assess alpha 1-adrenergic receptors on pineal gland membranes of male Syrian hamsters (Mesocricetus auratus) housed under a 14:10 h light-dark cycle (lights on at 06.00 h). Saturation experiments with pooled pineal membrane preparations showed the presence of alpha 1-adrenergic receptor sites (dissociation constant Kd approx. 0.1 nM). Analysis of 4 time points indicated no significant change in Kd, but significant (P less than 0.01) changes of receptor density (Bmax) with a minimum recorded at night. Binding of a constant amount of [125I]HEAT (200 pM) to pineal membranes at 8 time points exhibited a circadian variation (P less than 0.001) of receptor density with lowest values around midnight and highest levels during daytime.

Adrenergic alpha-Antagonists↗
PubMed1989

Predicting local recurrence of carcinoma of the rectum after preoperative radiotherapy and surgery.

A prospective study of prognostic factors has been carried out in a group of 186 patients with tethered rectal carcinomas. Of these, 97 were randomized to surgery alone and 89 to receive preoperative radiotherapy (20 Gy in four fractions). DNA ploidy was determined by flow cytometry. DNA aneuploidy was detected in 60 patients (62 per cent) in the surgery only group, but in only 33 patients (37 per cent) after radiotherapy (P less than 0.01). There was a significant reduction in local recurrence in irradiated patients (P less than 0.0001). DNA diploid tumours were less likely to recur locally. This was more marked in the radiotherapy group (P = 0.01) than in the surgery only group (P = 0.06). After radiotherapy, only the surgeons' assessments of a 'curative' resection and DNA ploidy were independent predictors of local recurrence in multivariate regression analysis, whilst Dukes' classification was not. In conclusion, DNA ploidy may indicate response to radiotherapy and is an important predictor of subsequent local tumour progression.

Combined Modality Therapy↗
PubMed1989

Characterization of beta-adrenoceptors in the Syrian hamster Harderian gland: sexual differences and effects of either castration or superior cervical ganglionectomy.

Scatchard analysis of saturation isotherms of [125I]-iodopindolol was used to characterize beta-adrenoceptor density (Bmax) and affinity constant (Kd) in female and male hamster Harderian glands. Single-point experiments were also completed in intact females, intact males, and castrated or superior cervical ganglionectomized males. Scatchard analysis described a single population of binding sites with a Bmax of 292.2 +/- 45.1 fmol/mg protein (X +/- SEM, n = 6) in females and 18.2 +/- 3.0 fmol/mg protein (n = 6, P less than .001) in males. The affinity also varied significantly (P less than .05) with a Kd of 1.08 +/- 0.18 versus 0.26 + 0.05 nM (n = 6) in the Harderian gland of females and males, respectively. Single-point [125I]-IPIN (400 pM) binding values in females were 67.3 +/- 4.0, in intact males were 12.8 +/- 3.2, and in castrated males were 31.2 +/- 4.2 fmol/mg protein (n = 7-9). Superior cervical ganglionectomy induced no significant changes in receptor binding. The results indicate pronounced sexual differences in the density and affinity of beta-adrenoceptors in the hamster Harderian gland, which may be sex hormone dependent.

Animals↗
PubMed1989

Ploidy as a prognostic indicator in oesophageal squamous carcinoma and its relationship to various histological criteria.

One hundred surgically resected squamous cell carcinomas of the oesophagus were studied retrospectively to assess the significance of DNA aneuploidy as determined by flow cytometry using paraffin-embedded tissue. DNA aneuploidy was not an independent prognostic indicator but was found to be associated with tumour necrosis and host/tumour interface fibrosis. When tumours confined to submucosa or muscle wall were assessed, diploid tumours had a poorer survival rate than DNA aneuploid tumours. Other histological variables studied were tumour differentiation, depth of infiltration, glandular and small cell differentiation, lymphatic and vascular spread and host inflammatory response. These failed to show any significant association with ploidy.

Adult↗
PubMed1989

Beta-adrenoceptors in the extraorbital lacrimal gland of the Syrian hamster. Characterization with [125I]-iodopindolol and evidence of sexual dimorphism.

Saturation and competition experiments with the radiolabeled beta-adrenergic antagonist (--)-[125I]-iodopindolol were used to characterized beta-adrenoceptor density (Bmax) and receptor affinity in the extraorbital lacrimal gland of male and female Syrian hamsters. Specific binding to the receptor was saturable. Scatchard analysis of saturation isotherms revealed a single population of receptor sites. Male glands had a significantly higher Bmax (38.9 +/- 5.0 vs. 23.3 +/- 2.1 fmol/mg protein, means +/- SEM, p less than 0.02) and receptor affinity (expressed in a lower dissociation constant Kd: 0.065 +/- 0.013 vs. 0.120 +/- 0.015 nM, p less than 0.02) than female glands. Binding of the radiolabeled ligand in competition with various adrenergic antagonists showed the receptor to be stereospecific and of the beta 2-subtype.

Adrenergic beta-Antagonists↗
PubMed1989

Detection of ras gene alterations and ras proteins in colorectal cancer.

DNA extracted from 31 primary colorectal carcinomas was analyzed for the presence of ras gene amplification and mutations. Nine carcinomas had Ha-ras amplification and seven Ki-ras amplification. Nine carcinomas had codon 12 Ki-ras mutations. Immunohistochemical staining for ras proteins revealed a normal membrane association in normal mucosa and benign polyps but an abnormal cytoplasmic distribution in carcinomas. Amplification, mutations, and immunohistochemical staining were independent of histologic differentiation, Dukes' stage, or DNA ploidy status. This study demonstrates that abnormalities of ras genes are a common finding in colorectal carcinomas. They are potentially important biologic changes associated with malignancy, although they do not appear to be related to clinical behavior.

Adult↗
PubMed1989

Modified Stamey procedure for bladder neck suspension.

A review of 76 patients who underwent endoscopic bladder neck suspension (EBNS) for stress incontinence is presented. Pre-operative video-urodynamic studies in 71 patients demonstrated stable stress incontinence in 61 (86%). There was a history of previous pelvic surgery in 52 patients (68%). Surgery was performed by trainee urologists in 35 cases (46%). The overall complication rate was 46%, of which 17% were per-operative and did not influence the outcome of surgery. Infection occurred in 16% and necessitated removal of the suture buffers in 9%. Follow-up ranged from 7 to 30 months (mean 18.3). Complete resolution of stress incontinence or a marked improvement in symptoms was seen in 86% of cases. Patients with no history of previous pelvic surgery were all either cured or improved by the procedure. Of the 52 patients who had undergone previous pelvic surgery, 42 (80%) were either cured or improved. All of the 10 failures were in this group. There was no difference between complication or success rates achieved by consultants or urologists in training. It was concluded that EBNS is the treatment of choice in patients with primary stress incontinence and it is an effective procedure in patients who have undergone previous unsuccessful surgery for stress incontinence.

Adult↗
PubMed1989

AIDS: the contamination risk in urological surgery.

Increasing numbers of patients infected with the Human Immunodeficiency Virus (HIV) will be encountered in surgical practice. The risk of exposure to the virus during urological surgery is unknown. In an attempt to quantify the risk and to identify procedures that require change, 427 consecutive urological operations were prospectively assessed for contamination of the surgeon's skin, face and mucous membranes by potentially infected body fluids. Contamination occurred in 136 procedures (32%), of which 37 of 123 (30%) were open operations and 99 of 304 (33%) were endoscopic. Contamination of the face and eyes accounted for 46% (46 of 99 operations) of the contamination occurring in endoscopic surgery. Attention must be paid to reducing exposure of the surgeons' skin to patients' body fluids. The surgeons' eyes should be protected by modification of urological techniques and equipment to avoid spillage.

Acquired Immunodeficiency Syndrome↗