Characterization of specular "dark events" in human donor corneal endothelium by scanning and transmission electron microscopy

PURPOSE

To evaluate changes in the donor corneal endothelium in the intact globe and in the in vivo rabbit cornea to characterize more fully the formation of "dark events" without relief images in the endothelial mosaic.

METHODS

Six ex vivo human donor corneas in the intact globe and an in vivo rabbit model were used to assess the morphological changes associated with osmotically increasing fluid movement from the anterior chamber into the stroma by specular (SM), confocal (CM), and transmission and scanning electron microscopy (TEM, SEM).

RESULTS

After application of hyperosmotic solution on the anterior surface of the cornea, dark events without relief images were observed by SM and CM. In both human and rabbit corneas, SEM showed that apical pores at the Y-junctions between endothelial cells became enlarged. Large subendothelial spaces were observed on Descemet's membrane by TEM with some spaces communicating with the anterior chamber.

CONCLUSIONS

The findings suggest that these openings at the Y-junctions may represent intercellular channels that may also act as pathways for the formation of intercellular and subendothelial vacuoles in both the rabbit and human donor corneal endothelium. By virtue of their location, these vacuoles are characterized by lack of relief images as seen with the contact SM.

Concentrating defect in experimental nephrotic syndrone: altered expression of aquaporins and thick ascending limb Na+ transporters

BACKGROUND

Several pathophysiological states associated with deranged water balance are associated with altered expression and/or intracellular distribution of aquaporin water channels. The possible role of dysregulation of thick ascending limb NaCl transporters, which are responsible for countercurrent multiplication in the kidney, has not been evaluated.

METHODS

Semiquantitative immunoblotting and immunocytochemistry were carried out in the kidneys of rat with adriamycin-induced nephrotic syndrome and in vehicle-injected control rats.

RESULTS

Preliminary studies confirmed the presence of a severe concentrating defect. Semiquantitative immunoblotting of outer medullary homogenates demonstrated a marked decrease in the abundance of three thick ascending limb Na+ transporters in nephrotic rats, namely the bumetanide-sensitive Na-K-2Cl cotransporter (BSC-1), the type 3 Na/H exchanger (NHE-3), and the alpha 1-subunit of the Na-K-ATPase. These results are predictive of a decrease in the NaCl transport capacity of the medullary thick ascending limb and therefore a decrease in countercurrent multiplication. Immunocytochemistry of outer medullary thin sections demonstrated broad (but highly variable) suppression of BSC-1 expression in the outer medullas of adriamycin-nephrotic rats. There was also a large decrease in outer medullary expression of two collecting duct water channels (aquaporin-2 and -3) and the major water channel of the thin descending limb of Henle's loop (aquaporin-1).

CONCLUSION

The concentrating defect in adriamycin-induced nephrotic syndrome in rats is a consequence of multiple defects in water and solute transporter expression, which would alter both the generation of medullary interstitial hypertonicity and osmotic equilibration in the collecting duct. Whether a similar widespread defect in transporter expression is present in idiopathic nephrotic syndrome is, at this point, untested.

Protocol design considerations that relate to demonstrating the safety and effectiveness of chemopreventive agents

As with other drugs, applications for marketing approval of new chemopreventive agents in the United States must include data from adequate and well-controlled clinical trials that demonstrate effectiveness and safety for the intended use. Knowledge of a drug's pharmacologic actions and metabolism may benefit protocol design, by identifying the patient populations and dosing schedules associated with a favorable risk/benefit profile. With availability of appropriate preclinical data, including standard assessments of an agent's toxicology, effects on reproductive performance, and genotoxicity, initial Phase I studies of 1-3 months may be performed in normal volunteers or an appropriate higher risk population. For chronic dosing studies of longer duration, preclinical toxicology studies of longer duration are relevant. Enrollment in chemoprevention studies should be directed toward individuals at sufficient risk of developing cancer so that potential benefit may counterbalance the unpredictable and possibly serious adverse effects that may be observed with prolonged administration of a study drug. Phase I and II studies with clinical dosing lasting up to 12 months often afford opportunities to assess drug effect on surrogate endpoint biomarkers that may correlate with endpoints of clinical effectiveness. Phase III and late phase II chemopreventive investigations should routinely utilize a prospective, randomized study design (double-masked and placebo-controlled, when possible). To support marketing approval, there must be evidence that a chemopreventive agent significantly delays or prevents the occurrence of malignancy, with acceptable safety. In some circumstances, modulation of a surrogate marker may provide a basis for marketing approval, before more definitive endpoint data become available. However, the acceptability of a surrogate depends on the nature and quality of the data supporting its predictive value. Given the considerations of large study size, long duration, and high cost that may hamper development of potential agents, studies designed to examine the predictive value of surrogate endpoint biomarkers are of great importance to the future development of chemoprevention research.

Impaired aquaporin and urea transporter expression in rats with adriamycin-induced nephrotic syndrome

Nephrotic syndrome is associated with abnormal regulation of renal water excretion. To investigate the role of collecting duct water channels and solute transporters in this process, we have carried out semiquantitative immunoblotting of kidney tissues from rats with adriamycin-induced nephrotic syndrome. These experiments demonstrated that adriamycin-induced nephrotic syndrome is associated with marked decreases in expression of aquaporin-2, aquaporin-3, aquaporin-4, and the vasopressin-regulated urea transporter in renal inner medulla, indicative of a suppression of the capacity for water and urea absorption by the inner medullary collecting duct. In contrast, expression of the alpha(1)-subunit of the Na,K-ATPase in the inner medulla was unaltered. Light and electron microscopy of perfusion-fixed kidneys demonstrated that the collecting ducts are morphologically normal and unobstructed. Inner medullary expression of the descending limb water channel, aquaporin-1, was not significantly altered, pointing to a selective effect on the collecting duct. Aquaporin-2 and aquaporin-3 expression was also markedly diminished in the renal cortex, indicating that the effect is not limited to the inner medullary collecting duct. Differential centrifugation studies and immunocytochemistry in inner medullary thin sections demonstrated increased targeting of aquaporin-2 to the plasma membrane, consistent with the expected short-term action of vasopressin on aquaporin-2 trafficking. The extensive down-regulation of aquaporin and urea transporter expression may represent an appropriate renal response to the extracellular volume expansion observed in nephrotic syndrome, but may occur at the expense of decreased urinary concentrating and diluting capacity.

The polypeptide backbone of recombinant human zona pellucida glycoprotein-3 initiates acrosomal exocytosis in human spermatozoa in vitro

Human gamete interaction is of fundamental biological importance, yet the molecular interactions between spermatozoa and the zona pellucida are poorly understood. Surprisingly, the role of the polypeptide backbone of zona pellucida glycoprotein 3 (ZP3), the putative ligand for spermatozoa activation, has been largely overlooked. Purified recombinant human ZP3 was expressed in Escherichia coli as a C-terminal fusion to the dimeric glutathione S-transferase (GST) from Schistosoma japonicum and was shown to induce acrosomal exocytosis in live, capacitated human spermatozoa. The level of exocytosis is comparable with that obtained using purified, glycosylated, recombinant human ZP3 [van Duin, M., Polman, J.E.M., DeBreet, I.T.M., Van Ginneken, K., Bunschoten, H., Grootenhuis, A., Brindle, J. and Aitken, R.J. (1994). Biol Reprod. 51, 607-617]. These data imply that the polypeptide chain of human ZP3 contributes to recognition of spermatozoa during acrosomal exocytosis in vitro.

Taphonomy and palaeoecology of Olduvai Bed-I (Pleistocence, Tanzania)

Detailed taxonomic and taphomonic studies of rodents and palaeoecological analysis have been undertaken to investigate faunal change in Olduvai Bed-I. The palaeoenvironments inferred from rodent faunas recorded in Olduvai Bed-I suggest a change between the middle (FLK + FLKNN) and the top of the series (FLKN). Changes have also been observed from taxonomic studies of large mammals and from palynological studies. These differences have been attributed in the past to climatic change, but taphonomic studies suggest a more complex scenario. The environment at Olduvai Bed-I is here interpreted through analysis of fossil faunas and fossilization processes. Identification of the causative agents that could have altered the faunal composition provides information on the environment and on the nature of the change observed between the middle and top of Bed-I. This information can then be used to test conflicting hypotheses about the origins and amount of faunal and pollen change. Results show evidence of predation in all units of Bed-I and can be attributed to different predators along the series. Different predator behaviours explain some of the variability observed by previous authors in the small mammal species composition between the middle and the top of Bed-I. After taking taphonomy into account, the remaining faunal differences point to environmental differences between middle and upper Bed-I and even greater within the upper Bed-I sequence. These differences go beyond the range that is present today in the tropical woodland-savanna biome. Our interpretation of the palaeoenvironments is that the middle Bed-I faunas indicate a very rich closed woodland environment, richer than any part of the present-day savanna biome in Africa, changing to less rich woodland in upper Bed-I with a trend towards more open and seasonal woodlands at the top of the series.

Aggressiveness of colon carcinoma in blacks and whites. National Cancer Institute Black/White Cancer Survival Study Group

Black patients with colon cancer in the Black/White Cancer Survival Study were found to have a poorer survival than white patients. More advanced-stage disease at diagnosis was the primary determinant, accounting for 60% of the excess mortality. After adjusting for stage, factors such as poverty, other socioeconomic conditions, and treatment did not further explain the remaining survival deficit. This study examined the aggressiveness of colon tumors in blacks and whites to explore its role in the racial survival differences. Tumor characteristics of 703 cases of newly diagnosed invasive colon adenocarcinoma were centrally evaluated by a gastrointestinal pathologist, blinded in regard to the age, race, and sex of the patients. Blacks were less likely to have poorly differentiated (grade 3) tumors [odds ratio (OR), 0.44; 95% confidence interval, 0.22-0.88] and lymphoid reaction (OR, 0.49; 95% confidence interval, 0.26-0.90) when compared with whites. These black/white (B/W) differences remained statistically significant after adjusting for age, sex, metropolitan area, summary stage, socioeconomic status, body mass index, and health care access and utilization. In addition, blacks were less likely to have high-grade (grade 3) nuclear atypia, mitotic activity, and tubule formation, although these ORs did not reach a statistical significance level of 0.05. Similar B/W differences were observed for patients with advanced disease but not with early stage. Comparison by anatomical subsite showed that blacks had statistically significantly better differentiated tumors for cancers of the proximal and transverse colon but not for the distal. No racial differences were found for blood vessel and lymphatic invasion, necrosis, fibrosis, and mucinous type of histology. The findings, therefore, are the opposite of those hypothesized. After adjusting for stage, more aggressive tumor characteristics do not explain the adverse survival differential in blacks. This suggests that there may be racial differences in environmental exposure, and that the intensity and mode of delivery of carcinogen insult as well as host susceptibility may differ by race and anatomical subsite. Future studies should explore the B/W differences in tumor biology using molecular markers that precede the conventional histological parameters evaluated here.

Surface modifications of the Sima de los Huesos fossil humans

The sample of fossil human bones from the Sima de los Huesos, Atapuerca, has been analysed to trace parts of its taphonomic history. The work reported here is restricted to analysis of the skeletal elements preserved and their surface modifications. Preliminary plans of specimen distribution published 6 years ago indicate that the skeletal elements are dispersed within the cave, but more recent data are not yet available. Most of the fossils are broken, with some breakage when the bone was fresh and some when already partly mineralized, both types showing some rounding. There are few longitudinal breaks on shafts of long bones and so very few bone splinters. All skeletal elements are preserved but in unequal proportions, with elements like femora, humeri and mandibles and teeth with greater structural density being best represented. There is no evidence of weathering or of human damage such as cut marks on any of the human assemblage, but trampling damage is present on most bones. Carnivore damage is also common, with some present on more than half the sample, but it is mostly superficial, either on the surfaces of shafts and articular ends or on the edges of spiral breaks. The sizes and distribution of the carnivore pits indicate extensive canid activity, and this is interpreted as scavenging of the bones in place in the cave. Indications of tooth marks from a larger carnivore indicate the activity possibly of a large felid: the marks are too large to be produced by small canids, with the larger marks concentrated on spiral breaks on the more robust bones, and there is no evidence of bone crushing and splintering in the manner of hyaenas. The nature of the SH human assemblage is also consistent with accumulation by humans, the evidence for this being the lack of other animals, especially the lack of herbivorous animals, associated with the humans, and the high number of individuals preserved.

Effect of hepatic methyl donor status on urinary excretion and DNA damage in B6C3F1 mice treated with sodium arsenite

This study evaluated the effect of hepatic methyl donor status on the ability of sodium arsenite (2.5, 5.0 and 10.0 mg/kg) administered by gavage once or on four consecutive days to induce DNA damage in male B6C3F1 mice. Maintenance on a choline-deficient (CD) diet prior to treatment resulted in mice with hepatic methyl donor deficiency (HMDD) and altered arsenical metabolism, as demonstrated by a decreased total urinary excretion of inorganic and organic arsenicals. The alkaline (pH > 13) Single Cell Gel (SCG) assay was used to evaluate for the induction of DNA damage (single strand breaks, alkali labile sites, DNA crosslinking) in blood leukocytes, liver parenchymal cells, and cells sampled from bladder, lung, and skin, while the bone marrow erythrocyte micronucleus (MN) assay was used to assess for the induction of chromosomal damage in bone marrow cells. Treatment with sodium arsenite once or four times induced a significant decrease in DNA migration (indicative of DNA crosslinking) in bladder and liver parenchymal cells of hepatic methyl donor sufficient (HMDS) mice, but in skin cells of HMDD mice. Both HMDD and HMDS mice exhibited a significant increase in the frequency of micronucleated polychromatic erythrocytes (MN-PCE) in bone marrow following four, but not following one, treatments. However, the positive response occurred at a lower dose for HMDS mice and, in these mice, bone marrow toxicity, as demonstrated by a significant reduction in the percentage of PCE, was present also. These results indicate that hepatic methyl donors deficiency significantly decreases the total urinary excretion of orally administered sodium arsenite and markedly modulates target organ arsenic-induced DNA damage, with an apparent shift from liver and bladder to skin.

Comparison of the modified vest and the direct anastomosis for radical retropubic prostatectomy

OBJECTIVES

This retrospective study was undertaken to compare the efficacy of the Vest and direct vesicourethral anastomosis for radical prostatectomy.

METHODS

Five hundred six patients who underwent consecutive radical prostatectomies at our institution were analyzed. Two hundred fifty-nine patients underwent vesicourethral anastomosis using the Vest technique and 247 underwent a direct suture anastomosis. The groups were analyzed relative to time until healing, the occurrence of anastomotic strictures, and the continence rate 1 year after surgery.

RESULTS

Approximately twice as many patients who underwent the Vest procedure experienced delayed healing and 8.5% developed anastomotic strictures compared with 1.2% of the direct anastomosis group. The Vest group experienced slightly better urinary continence 1 year postoperatively.

CONCLUSIONS

The Vest procedure is a reasonable alternative to direct anastomosis for radical prostatectomy and provides similar results. We suggest specific circumstances when the Vest anastomosis may be particularly useful.

Cocaethylene toxicity

Concurrent use of cocaine and alcohol produces another psychoactive substance known as cocaethylene which has pharmacological properties similar to that of cocaine but which has a plasma half-life three to five times that of cocaine. This slow removal from the body makes it an attractive drug for abuse. However, cocaethylene has been associated with seizures, liver damage, and compromised functioning of the immune system. It also carries an 18- to 25-fold increase over cocaine alone in risk for immediate death.

Reduced renal medullary water channel expression in puromycin aminonucleoside--induced nephrotic syndrome

The aquaporins are molecular water channels that mediate transcellular water transport across water-permeable epithelia. To investigate the cause of the concentrating defect in the nephrotic syndrome, immunoblotting using membrane fractions from inner medulla was utilized to assess the level of expression of four aquaporin water channels in vehicle-treated versus puromycin aminonucleoside (PAN)-treated rats. Scanning electron microscopy demonstrating loss of glomerular foot processes and measurements of urinary protein excretion confirmed the efficacy of the PAN treatment. In rats receiving PAN, there was an increase in plasma vasopressin, without a change in plasma sodium concentration. Inner medullary tissue hypertonicity was sustained in PAN-treated rats while the urinary osmolality was low, pointing to defective osmotic equilibration across the collecting ducts in PAN-nephrosis. Among collecting duct aquaporins, there was an 87% decrease in aquaporin-2 expression and a 70% decrease in aquaporin-3 expression in the inner medulla, whereas aquaporin-4 expression was unaltered. Transmission electron microscopy of the inner medullary collecting ducts of PAN-treated rats showed normal-appearing cells. Thus, PAN-nephrosis is associated with an extensive downregulation of collecting duct water channel expression despite increased circulating vasopressin, providing an explanation for the concentrating defect associated with the nephrotic syndrome.

Evaluation of whole blood antibody kit to detect active Helicobacter pylori infection

OBJECTIVES

To evaluate the sensitivity and specificity of a whole blood antibody test (Helisal Rapid Blood test) for the detection of Helicobacter pylori using endoscopic diagnostic criteria of histology and urease tests as the "gold standard."

METHODS

A prospective trial of Helisal Rapid Blood (HRB) test was carried out in patients undergoing investigations for dyspepsia that included endoscopic biopsy for rapid urease test, microbiological culture, and histology. Blood samples were obtained at the time of endoscopy and were tested for the presence of antibody to H. pylori using the HRB test. In a separate patient group, results of antibody tests in whole venous and capillary blood were compared (n = 25).

RESULTS

The rapid blood test was carried out immediately after the endoscopic examination with a result available in under 10 min in all cases. In 203 patients examined, the HRB test detected 70 of 203 to be H. pylori positive as compared with 71 of 203 using urease/histology. Against combined urease/histology tests, the HRB test achieved 82% sensitivity and 91% specificity. Five patients were judged to be "false negative" on endoscopic tests for H. pylori (extensive intestinal metaplasia n = 3; recent use of antimicrobials) yet the HRB test diagnosed the presence of infection, which could be shown to resolve on treatment. The HRB achieved 89% sensitivity and 91% specificity upon correctly including these five patients in the calculations. In all 25 patients tested, venous and capillary blood results concurred giving HRB test positivity in each case.

CONCLUSIONS

Whether using whole venous or capillary blood, the HRB test is a quick, convenient, and accurate test for the diagnosis of active H. pylori infection in patients previously not treated. In a subgroup of patients with low level infection due to recent antimicrobials or intestinal metaplasia negative to all endoscopic tests, the blood test can still correctly diagnose H. pylori infection. Because blood samples require no centrifugation before testing, the greatest usefulness of this test will be that of a primary office diagnostic device.

Comparative trial of steroids and surgical intervention in the management of ulnar neuritis

Fifty-seven ulnar nerves in 39 patients with early neuritis were studied to assess the benefits offered by medial epicondylectomy and external decompression in addition to steroid therapy. The patients were randomly allocated to the surgical or medical group. In those cases where there was bilateral involvement, surgery was carried out on only one side. All cases were assessed prior to treatment and after the first and second years following treatment. The improvement in motor and sensory functions attained at the end of the first year was sustained into the second year. The improvement sustained in both groups was similar even in the second year, and medial epicondylectomy with external decompression seems to have no added benefit as compared to steroid therapy alone in the early treatment of ulnar neuritis. Early diagnosis and treatment, especially in borderline lepromatous cases, seem to offer some hope of nerve function recovery.

A new specimen of Ankarapithecus meteai from the Sinap Formation of central Anatolia

Hominoid fossils from the Middle and Late Miocene are exceedingly rare, yet such material is necessary for determining hominoid phylogeny. We report here the discovery of a fossil hominoid partial skull from the Upper Miocene Sinap Formation of central Turkey that is the most complete known from the period of 18 to 3 Myr. Our fieldwork places the hominoid locality within a precisely dated geochronological and biostratigraphical framework that permits detailed comparisons with other fossil hominoids. Earlier discoveries of more fragmentary remains of Ankarapithecus meteai suggested affinities with the Asian hominoids Sivapithecus and Pongo. This new and nearly complete specimen reveals a combination of facial, mandibular, and dental features including a relatively narrow interorbital region, extensive frontal and maxillary sinuses, moderately developed supraorbital tori, square orbits, robust mandibular corpus, and incisor heteromorphy that is not matched in any extant or fossil hominoid. This configuration of features seems to support its placement as a stem member of the great ape and human clade.

The pharmacology of the emetic response to upper gastrointestinal tract stimulation in Suncus murinus

This paper is the first to describe aspects of the mechanics of retching in the insectivore Suncus murinus (house musk shrew) and in an animal of such a small size (approximately 50 g). In anaesthetised animals using the novel stimulus of mechanical stimulation of the upper gastrointestinal tract as the provocative stimulus the frequency of retching was found to be about 4 retches/s, a much higher frequency than in other species (dog, cat, ferret). These studies show that quantification of retching in Suncus cannot be undertaken using direct observation. The temporal pattern of the emetic response was characterised in conscious Suncus using motion (1 Hz, 5 min) and nicotine (20 mg/kg s.c.). The ultrapotent capsaicin analogue resiniferatoxin (100 micrograms/kg s.c.) was discovered to be highly emetic and comparative studies showed that nicotine and resiniferatoxin induced the most intense responses with episodes (retches and a vomit) occurring every 10-15 s. The retching response to mechanical stimulation in the anaesthetised Suncus was not blocked by a 5-HT3 receptor antagonist (granisetron, 1-5 mg/kg s.c.), a tachykinin NK1 receptor antagonist (CP-99,994 20 mg/kg s.c. dihydrochloride salt (9+) -(2S,3S)-3-(2-methoxybenzylamino)-2-phenylpiperidine) or morphine (2 mg/kg s.c.) but was blocked by the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT 100 micrograms/kg s.c.). Suncus appears to be a suitable animal in which to study the pharmacology of the emetic response to mechanical stimulation of the gut. The results are discussed in the light of studies of the pharmacology of emesis in other species.

Acute renal failure as a complication of acute pancreatitis

To assess the prevalence of acute renal failure (ARF) in patients with acute pancreatitis, as well as the factors predictive of a lethal outcome, we retrospectively studied the data of all patients admitted to our hospital over a 5-year period. Between 1989 and 1993, 554 patients presented with acute pancreatitis, of which 24 (4.4%) subsequently developed ARF. Death occurred in 14/24 (58%) of patients with ARF, and was associated with an increased incidence of multiorgan failure. There was no statistically significant difference in the age, admission blood pressure, or admission pulse rate of the patients who survived and those who died. In contrast, death was associated with a higher Ranson score, and the increased prevalence of multiorgan failure. The length of hospitalization of the nonsurviving group was significantly shorter. Acute renal failure is not a common finding in patients with acute pancreatitis. However, when it occurs, it is associated with a poor prognosis, and is predicted by a higher Ranson score and the presence of multiorgan failure.

Capillary GC-ECD and ECNI GCMS characterization of toxaphene residues in primate tissues during a feeding study

Toxaphene is a pesticide whose use was banned in North America because of concerns regarding its toxicity. To obtain better data on the metabolism and toxicity of toxaphene in primates, a one year feeding study was carried out in cynomologous monkeys at a dose of 1 mg/kg/day for one year. Levels of toxaphene residues in blood and adipose tissue during the dosing period were measured by GC-ECD and ECNI GCMS. The dosing toxaphene mixture was found to be extensively metabolized. Four chlorinated bornane congeners were the predominate residues found in the tissue samples. Blood levels of toxaphene residues plateaued at 40 ppb, adipose levels at approximately 4000 ppb. Kidney, liver, feces and urine were analyzed for toxaphene residues after necropsy.

Omeprazole enhances efficacy of triple therapy in eradicating Helicobacter pylori

Triple therapy has been recommended as the most effective treatment for Helicobacter pylori eradication. Despite achieving a comparatively high eradication result, however, around 10% of patients still fail to be cured. Omeprazole can enhance efficacy of single and double antibiotic protocols and is particularly effective when combined with clarithromycin and a nitroimidazole. This study examined the effect of combining triple therapy with omeprazole. A prospective, randomised, unblinded, single centre trial was carried out on consecutive patients with symptoms of dyspepsia and H pylori infection confirmed by rapid urease test, microbiological culture, and histological assessment. Patients were given a five times/day, 12 day course of colloidal bismuth subcitrate chewable tablets (108 mg), tetracycline HCl (250 mg), and metronidazole (200 mg) with either 20 mg omeprazole twice daily (triple therapy+omeprazole) or 40 mg famotidine (triple therapy+famotidine) at night. Compliance and side effects were determined using a standard questionnaire form. One hundred and twenty five of 165 triple therapy+omeprazole patients and 124 of 171 triple therapy+famotidine patients returned for rebiopsy four weeks after completion of treatment. Significantly more triple therapy+omeprazole patients achieved eradication 122 of 125 (97.6%) as assessed by negative urease test, culture, and histological assessment, when compared with 110 of 124 (89%) triple therapy+famotidine patients (p = 0.006; chi 2). There were 30 triple therapy+omeprazole (24%) and 26 triple therapy+famotidine (21%) patients with de novo metronidazole resistant H pylori included in the study. Side effects were mild and infrequent and were comparable in both groups, although pain in duodenal ulcer, gastric ulcer, and oesophagitis patients seemed to subside earlier in those taking omeprazole. Compliance (>95% of drugs taken) was achieved by 98% of patients of both groups. A 12 days regimen of triple therapy with omeprazole is more effective in achieving H pylori eradication than is triple therapy plus famotidine. Use of 20 mg omeprazole twice daily rather than 40 mg famotidine with a 12 day, low dose triple therapy enhances eradication to over 97% whether the H pylori is metronidazole sensitive or resistant.

Expression and androgenic regulation of human prostate-specific kallikreins

In vitro studies suggest that the protease activity of PSA might play a functional role to facilitate the growth and spreading of cancerous prostatic cells. hK2 may have similar properties. Further investigation to prove their in vivo effects is required. Regulation of PSA and hKLK2 gene expression is mediated not only by androgens, but also by a number of autocrine and paracrine factors, suggesting that the control mechanisms for expression of these genes are complex and multifaceted. Such factors may also be integral for the growth and differentiation of prostate cells. Thus PSA and hKLK2 may serve as useful markers to study the regulation of gene expression during cell growth and differentiation of the prostate.