PubMed Health⌕ Search

Biomedical subjects

H L Jones

Publications and source records attributed to H L Jones.

At least 19 recordsLinked to original sources
PubMed2001

Induction of tyrosinase gene transcription in human iris organ cultures exposed to latanoprost.

OBJECTIVE: Topical administration of latanoprost sometimes induces gradual iris darkening. The present study was undertaken to determine if latanoprost can increase transcription of the gene for tyrosinase, an important enzyme in the biosynthesis of melanin. Results from brown, hazel, and blue irides were compared. METHODS: Iris tissue was isolated from 30 pairs of postmortem human donor eyes, and 2 iris segments from each eye were incubated in tissue culture medium supplemented with 200nM latanoprost acid or vehicle for 7 days. Tyrosinase messenger RNA (mRNA) was determined using real-time polymerase chain reaction analysis (TaqMan quantitative polymerase chain reaction). Results for tyrosinase mRNA were normalized according to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA in each sample. RESULTS: Tyrosinase mRNA expression was similar in blue and hazel irides, and ranged from 0.7-fold to 12.6-fold greater than GAPDH expression. In contrast, control brown iris culture tyrosinase expression ranged from 6.4-fold to 265-fold greater than GAPDH expression. Induction of tyrosinase mRNA by latanoprost was below threshold in all the blue iris cultures (n = 8 pairs), present in 1 of 9 hazel iris cultures, and present in 5 of 13 brown iris cultures. Mean induction in the responding hazel iris cultures was 1.40-fold. Mean induction among the responding brown iris cultures was 2.97-fold. CONCLUSIONS: These observations support the view that iris darkening associated with latanoprost treatment reflects induction of tyrosinase expression. Moreover, they suggest that the probability that latanoprost will increase tyrosinase expression is directly related to the magnitude of tyrosinase expression before treatments are initiated. CLINICAL RELEVANCE: The variability of iris darkening with latanoprost may reflect natural variation in the basal transcription of tyrosinase.

Adult↗
PubMed2001

Laparoscopic hiatal hernia repair in patients with poor esophageal motility or paraesophageal herniation.

Laparoscopic repair for gastroesophageal reflux disease is now an accepted therapy. However, controversy exists with regard to the choice of operation between complete 360-degree Nissen fundoplication versus partial 270-degree Toupe fundoplication. In addition there is some controversy with regard to the proper choice of operation in patients with poor esophageal motility. Another class of hiatal hernia patients are those patients with paraesophageal herniation. Questions regarding the approach to these patients include whether or not to use a reflux procedure at the time of repair and the role of mesh in repair of these large hernias. This retrospective study was undertaken to compare the results of laparoscopic Nissen fundoplication and Toupe fundoplication in patients with both normal and abnormal esophageal motility. In addition the subset of patients with paraesophageal herniation was studied in an effort to ascertain the best surgical approach in these patients. In this study a retrospective analysis was performed on 188 consecutive patients during the period 1995 to 2001. All patients who presented with hiatal hernia surgical problems during this period were included. Endoscopy was performed in all patients with esophageal reflux. Manometry was performed in all patients except those presenting as emergency incarcerations. pH probe testing was performed in those patients in whom it was deemed necessary to establish the diagnosis. Upper gastrointestinal radiographs were used to define anatomy in paraesophageal hernia patients when possible. All patients with esophageal reflux were first treated with a trial of medical therapy. Patients with esophageal reflux and normal esophageal motility underwent 360-degree Nissen fundoplication. Those patients with poor esophageal motility (less than 65 mm of mercury) underwent laparoscopic 270-degree Toupe fundoplication. Patients presenting with paraesophageal herniation underwent laparoscopic repair. When possible esophageal manometry was performed on these patients preoperatively and if normal peristalsis was documented a Nissen fundoplication was performed. If poor esophageal motility was documented before surgery a Toupe fundoplication was performed. Mesh reinforcement of the diaphragmatic hiatus was used if necessary to complete a repair without tension. Patients were followed both by their primary gastroenterologist and their surgeon. Follow-up studies including endoscopy, pH probe, and upper gastrointestinal series were used as necessary in the postoperative period to document any problems as they occurred. Of the 188 patients in the study 141 patients underwent Nissen fundoplication, 21 patients underwent Nissen fundoplication and repair of paraesophageal hernia, 15 underwent Toupe fundoplication, seven underwent Toupe and paraesophageal hernia repair, and four paraesophageal hernia repair alone. One hundred eighty-three patients underwent a laparoscopic operation. Five patients of the 188 underwent an initial open operation-two of these patients because of the size of their paraesophageal hernia. Three of these patients had reoperations of remote operations done years before at other institutions. Twenty-two patients with poor esophageal motility (11.7 %) were included in the study. Fifteen patients required Toupe fundoplication whereas seven patients required Toupe fundoplication and repair of paraesophageal hernias. Mesh repair of paraesophageal hernias was accomplished in ten patients. Patients undergoing Toupe fundoplication had a 13 per cent dysphagia rate less than 4 weeks postoperatively and a 0% dysphagia rate greater than four weeks postoperatively. Patients undergoing Nissen fundoplication had a 16 per cent dysphagia rate less than 4 weeks postoperatively, 2 per cent dysphagia rate greater than 4 weeks postoperatively and no dysphagia at 6 weeks postoperatively. Recurrent symptomatic reflux occurred in 1.4 per cent of Nissen fundoplications and 6.7 per cent of Toupe fundoplications. Of Nissen and paraesophageal repairs 14.2 per cent had reflux and 14.3 per cent of Toupe and paraesophageal repairs had recurrent symptomatic reflux. Overall, complication rate was low. Use of mesh to repair large paraesophageal hernias resulted in a recurrence rate of 0 per cent. There was no instance of infection or bowel fistulization related to the use of mesh. We conclude that laparoscopic Nissen fundoplication in patients with normal esophageal motility is associated with a low rate of dysphagia and a low rate of recurrent reflux. Toupe fundoplication when used in reflux patients with poor esophageal motility is associated with a low rate of dysphagia and an acceptable rate of recurrent reflux. Laparoscop

Adult↗
PubMed2000

Second stage of a genome scan of schizophrenia: study of five positive regions in an expanded sample.

In a previous genome scan of 43 schizophrenia pedigrees, nonparametric linkage (NPL) scores with empirically derived pointwise P-values less than 0.01 were observed in two regions (chromosomes 2q12-13 and 10q23) and less than 0.05 in three regions (4q22-23, 9q22, and 11q21). Markers with a mean spacing of about 5 cM were typed in these regions in an expanded sample of 71 pedigrees, and NPL analyses carried out. No region produced significant genomewide evidence for linkage. On chromosome 10q, the empirical P-value remained at less than 0.01 for the entire sample (D10S168), evidence in the original 43 pedigrees was slightly increased, and a broad peak of positive results was observed. P-values less than 0.05 were observed on chromosomes 2q (D2S436) and 4q (D4S2623), but not on chromosomes 9q or 11q. It is concluded that this sample is most supportive of linkage on chromosome 10q, with less consistent support on chromosomes 2q and 4q. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:864-869, 2000.

Alleles↗
PubMed2000

Laparoscopic repair of bilateral inguinal hernias in a patient with müllerian agenesis.

OBJECTIVE: To report a case of laparoscopic repair of bilateral inguinal hernias in a patient with müllerian agenesis. DESIGN: Case report. SETTING: Hospital. PATIENT(S): An 18-year-old woman with müllerian agenesis who presented with symptomatic inguinal hernias containing ovaries. INTERVENTION(S): Laparoscopic repair of bilateral inguinal hernias. MAIN OUTCOME MEASURE(S): Hernia repair was accomplished laparoscopically. RESULT(S): Outpatient laparoscopic repair of bilateral inguinal hernias with reduction of ovaries was performed using an extraperitoneal approach without complication. CONCLUSION(S): Laparoscopic approach of inguinal hernias can be an option for surgical repair in patients with müllerian agenesis even when the hernias contain ovaries.

Adult↗
PubMed1998

Genome scan of schizophrenia.

OBJECTIVE: The goal of this study was to identify chromosomal regions likely to contain schizophrenia susceptibility genes. METHOD: A genomewide map of 310 microsatellite DNA markers with average spacing of 11 centimorgans was genotyped in 269 individuals--126 of them with schizophrenia-related psychoses--from 43 pedigrees. Nonparametric linkage analysis was used to assess the pattern of allele sharing at each marker locus relative to the presence of disease. RESULTS: Nonparametric linkage scores did not reach a genomewide level of statistical significance for any marker. There were five chromosomal regions in which empirically derived p values reached nominal levels of significance at eight marker locations. There were p values less than 0.01 at chromosomes 2q (with the peak value in this region at D2S410) and 10q (D10S1239), and there were p values less than 0.05 at chromosomes 4q (D4S2623), 9q (D9S257), and 11q (D11S2002). CONCLUSIONS: The results do not support the hypothesis that a single gene causes a large increase in the risk of schizophrenia. The sample (like most others being studied for psychiatric disorders) has limited power to detect genes of small effect or those that are determinants of risk in a small proportion of families. All of the most positive results could be due to chance, or some could reflect weak linkage (genes of small effect). Multicenter studies may be useful in the effort to identify chromosomal regions most likely to contain schizophrenia susceptibility genes.

Chromosome Mapping↗
PubMed1997

Polyclonal Ki-67 expression in transitional cell carcinoma of the bladder.

The proliferation kinetics of 101 cases of transitional cell carcinoma (TCC) and seven cases of transitional cell carcinoma-in-situ of the bladder were assessed following staining with polyclonal Ki-67 antibody (pKi-67). Labeling indices ranged from 49% to 60.2% with a mean value of 22.2% for all cases. A significant association between pKi-67 indices, tumor grade and tumor stage was observed, with significant differences between pKi-67 indices of Grade 1 and 3 tumors and Grade 2 and 3 tumors. Significant differences in labeling indices were also found between superficial (Ta) tumors and both musculoinvasive (T2/T3a) tumors and those infiltrating the perivesical fat (T3b). pKi-67 indices for carcinoma-in-situ were similar to those noted for Grade 1 TCC. No difference in pKi-67 index was found when tumors were classified according to the morphology of the tumor invasion front. It is concluded that pKi-67 index is a useful marker for tumor progression for vesical TCC and that this immunohistochemical stain may assist clinical assessment of the potential behaviour of tumors in individual cases.

Antigens, Neoplasm↗
PubMed1994

Multiple pancreatic abscesses due to Candida albicans following ERCP.

A report is presented of a patient who developed multiple abscesses of the pancreas due to Candida albicans following an Endoscopic retrograde chole-pancreatography (ERCP) for acute pancreatitis. He was not immunocompromised, debilitated and had not had recent surgery. There was complete radiological and clinical resolution of the abscess on prolonged treatment with amphotericin alone. Only a few cases of candidal abscess of the pancreas have been reported, none of them having occurred after an ERCP.

Abscess↗
PubMed1993

Doramectin, a new avermectin highly efficacious against gastrointestinal nematodes and lungworms of cattle and pigs: two studies carried out under field conditions in Germany.

Two field studies were carried out to confirm the efficacy of doramectin in cattle and pigs in Europe. A total of 40 cattle harbouring naturally acquired infections of gastrointestinal nematodes, including Ostertagia spp., Oesophagostomum spp., Cooperia spp., Haemonchus spp., Nematodirus spp. and Trichuris spp., were allocated to a treated or a control group (20 animals/group), and 100 harbouring naturally acquired infections of gastrointestinal nematodes and lungworms, including Oesophagostomum spp., Metastrongylus spp., Ascaris suum and Trichuris suis, were allocated to either a treated (60 pigs) or a control (40 pigs) group. Animals in the treated groups received an injection of doramectin at 200 micrograms/kg (1 ml/50 kg) for cattle or 300 micrograms/kg (1 ml/33 kg) for swine. Animals in the control groups received saline at 1 ml/50 kg for cattle or 1 ml/33 kg for swine. The cattle were injected by the subcutaneous route in the lateral mid-line of the neck and the pigs were injected intramuscularly in the neck. Faecal egg counts were determined for all animals on days--7, 0, 7, 14 and 21 of the studies, where day 0 was the day of treatment. The mean daily weight gain of doramectin-treated animals was significantly higher than that of the control animals over the 21 days of the studies (P < 0.0007 for cattle and P = 0.0001 for swine). At 21 days after treatment, the mean faecal egg counts of the doramectin-treated animals were significantly lower than those of the control animals and were reduced by 100% as compared with pretreatment levels. No adverse reaction to treatment was observed in any animal during either study.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Massive hepatic necrosis in toxemia of pregnancy.

Hepatic rupture and infarction associated with toxemia of pregnancy usually occur in multiparous women close to 30 years of age. The most important presenting symptom is right upper-quadrant abdominal pain. Sonography is the most expedient way of making the diagnosis of either rupture or hemorrhagic necrosis, but computed tomography is more sensitive. Elevated transaminase levels and thrombocytopenia or disseminated intravascular coagulation may occur acutely but resolve quickly. Termination of pregnancy is the cornerstone of any treatment plan. Many cases may not require operative treatment other than inspection. In others, surgical hemostasis will be lifesaving. We describe four preeclamptic women, two with ruptured subcapsular hematomas and two with hemorrhagic infarction. Radiological and laboratory evidence of liver damage and recovery are presented.

Adult↗
PubMed1989

A quality assessment of the effects of a hydrogenous filter on a p(66)Be(40) neutron beam.

Recent measurements in a p(62)Be(36) neutron therapy beam have shown that the quality of the in-phantom beam changes with depth. This variation can be ascribed to the presence of a relatively large low-energy neutron component emanating from the neutron source. As part of the pre-clinical calibration programme at a newly commissioned neutron therapy facility, radiobiological and microdosimetric observations were made to determine the magnitude of this effect on a p(66)Be(40) beam and to evaluate the hardening effect of a hydrogenous filter. The reported data identify a correlation between the two assays and quantify a linear relationship between y* and filter thicknesses less than or equal to 6 cm. Using the data obtained in the study, a filter thickness was selected to comply with clinical requirements. By employing lineal energy spectra, it is demonstrated that subtle changes in beam quality may be quantified in a reproducible manner without resorting to time-consuming radiobiological studies.

Animals↗