Helicobacter pylori eradication with doxycycline-metronidazole-bismuth subcitrate triple therapy

Triple therapy containing tetracycline HCl is currently among the most efficient combination therapies for eradication of Helicobacter pylori. Substitution of doxycycline for tetracycline HCl offers advantages of less frequent dosing and extrarenal excretion. In this study patients with duodenal ulcer or non-ulcer dyspepsia positive for H. pylori were randomized to either doxycycline or tetracycline HCl triple therapy in conjunction with bismuth subcitrate and metronidazole. Of the 34 patients taking doxycycline, only 22 (65%) achieved H. pylori eradication at the 4-week rebiopsy, compared with 36 of 39 (92%) taking tetracycline HCl (p = 0.004). We conclude that doxycycline-containing triple therapy is less effective for H. pylori eradication and offers no clinical advantage over tetracycline HCl-containing triple therapy.

Tumor-promoting phorbol ester down-regulates the androgen induction of prostate-specific antigen in a human prostatic adenocarcinoma cell line

Prostate-specific antigen (PSA) is the most sensitive marker available for monitoring the progression of prostate cancer and response to therapy. In a previous study, we demonstrated tissue-specific expression of PSA glycoprotein and mRNA and its regulation through the androgen receptor. In this study, we examine the effects of protein kinase A (PKA) and protein kinase C (PKC) on the androgen regulation of PSA in a human adenocarcinoma cell line, LNCaP. Northern blot analysis demonstrated that forskolin, an activator of PKA, had no effect on the androgen regulation of PSA. However, the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA), a direct activator of PKC, showed a time- and dose-dependent repression of the androgen regulation of PSA glycoprotein and mRNA. The biologically inactive phorbol ester, 4 alpha-phorbol-12,13-didecanoate, had no effect. Staurosporine, a PKC inhibitor, blocked the TPA-mediated repression of the androgenic stimulation of PSA glycoprotein. In addition, the calcium ionophore, A23187, was able to simulate the actions of TPA, presumably through activation of PKC via calcium mobilization. In summary, the androgenic regulation of PSA protein and mRNA is repressed by tumor-promoting phorbol esters through the PKC pathway. This indicates that the effects of TPA may be secondary to repressed gene transcription or altered mRNA stability. In addition, this study emphasizes that the androgenic regulation of PSA is complex and may involve other extracellular transduction signals.

Tissue-specific and hormonal regulation of human prostate-specific glandular kallikrein

Kallikreins are involved in the posttranslational processing of a number of specific polypeptide precursors. Previously, human glandular kallikrein (hGK-1) mRNA has been identified in the prostate; however, the hGK-1 protein has not been identified and characterized. Therefore, its physiologic function in the prostate is not known. In this study, we have isolated a full-length hGK-1 cDNA from a human adenocarcinoma cell line, LNCaP. In vitro translation experiments demonstrated that the molecular size of the hGK-1 protein generated from this cDNA is similar to that of prostate-specific antigen (PSA), a protein which is produced exclusively in the prostate. In situ hybridization with a hGK-1-specific oligonucleotide probe (77 bases), which can differentiate hGK-1 mRNA from PSA mRNA, demonstrated the hGK-1 mRNA to be located in the prostate epithelium. The hGK-1 mRNA was colocalized with PSA mRNA in prostatic epithelia. Moreover, in situ hybridization studies revealed that the level of hGK-1 mRNA in human benign prostatic hyperplasia tissues is approximately half that of PSA mRNA. Furthermore, we have demonstrated that hGK-1 mRNA is under androgenic regulation in LNCaP cells. Time course analysis revealed that hGK-1 mRNA levels increased significantly at 5 h of mibolerone treatment and reached maximal levels by 9 h. In addition, hGK-1 mRNA levels were increased by dihydrotestosterone, but not by dexamethasone or diethylstilbestrol treatments. Flutamide, a nonmetabolized anti-androgen, repressed the androgenic effects. These studies suggest that expression of hGK-1 mRNA is regulated by androgen via the androgen receptor.

Hormonal regulation of prostate-specific antigen (PSA) glycoprotein in the human prostatic adenocarcinoma cell line, LNCaP

Prostate-specific antigen (PSA) has emerged as the most useful marker for management of patients with prostate cancer. The regulation of this glycoprotein in vivo has important clinical implications. Indirect evidence indicates that the PSA glycoprotein might be regulated by androgens, and previous studies in this laboratory have demonstrated that PSA mRNA is upregulated by androgens. The current work reports a detailed study of PSA glycoprotein expression as influenced by steroid hormones in a human prostatic adenocarcinoma cell line, LNCaP. First, we have examined the steroid binding specificity of the androgen receptor in this cell line. In comparison with wild-type rat androgen receptor in prostate, the receptor in LNCaP cells has altered affinity for a number of steroids or analogs such as progesterone (R5020), antiprogesterone (RU486), two antiandrogens (cyperoterone acetate and hydroxyflutamide), and an androgen metabolite (epitestosterone). However, its affinity for androgens (mibolerone, dihydrotestosterone, and testosterone) is not changed. The receptor does not bind to the synthetic glucocorticoids (triaminolone acetonide and dexamethasone) nor to a synthetic estrogen DES (diethylstilbestrol). The change of the steroid binding specificity of the receptor is correlated with a single mutation (A----G at nucleotide #876 relative to the initiation codon) of the steroid binding domain of the receptor. The mutation and alteration of steroid-binding specificity of the androgen receptor is also correlated with PSA glycoprotein expression affected by different ligands tested. We have demonstrated that the PSA glycoprotein is upregulated by androgens and is affected by neither epidermal growth factor nor basic fibroblast growth factor. Moreover, PSA glycoprotein could be induced by R5020, estradiol, and epitestosterone; but neither glucocorticoids nor DES had any effect on PSA induction. Interestingly, although the antiandrogen, cyperotone acetate, had the ability to induce PSA, both RU486 and hydroxyflutamide could block androgen and progesterone induction of PSA glycoprotein. Therefore, we conclude that the PSA glycoprotein expression is influenced predominantly by androgens via its receptor, and the mutation of the receptor can affect the expression of this cellular gene by the steroids other than androgens.

Action spectrum of antiviral factor from chicken sera

Rous sarcoma virus infections of regressor line chickens stimulate the transient production of antiviral factors in the serum. Earlier the present authors reported that a viral neutralization factor (VNF) inactivated Rous sarcoma virus during a 3-h incubation. The VNF is likely to have a broad antiviral and antimicrobial spectrum because it is active against several unrelated pathogenic poultry viruses. The present study measured the activity of VNF against Newcastle disease virus, infectious bursal disease virus, and infectious bronchitis virus. The VNF is active in immunologically incompetent systems and must be preincubated with the virus in order to inhibit it. Based upon the current experiments, it is proposed that VNF is not an immunomodulator but directly inactivates the virus. The VNF agent appears to be one of a newly identified class of nonspecific antiviral agents produced in vivo in chickens in response to a viral infection.

Hominoid dietary evolution

During the later Palaeocene and early Miocene, catarrhine primates and the evolving hominoids had adaptations for frugivorous diets, with the emphasis on soft foods. Early in the middle Miocene the hominoids underwent a major shift, both in morphology and in habitat, with the morphology characterized by thickened enamel on the molars, enlarged incisors and massive jaws. The diet indicated by this morphology is interpreted as still mainly frugivorous but with changed emphasis, possibly towards harder objects. The thick-enamelled hominoids are found associated with more open forest habitats, and the distribution of food resources in equivalent habitats today is discontinuous both in time and in space, leading to evolutionary pressures particularly affecting locomotion, brain size and social behaviour. The earliest known hominid fossils differed little in dental and mandibular morphology from the middle Miocene apes, and the implied dietary similarity, together with ape-like patterns of dental development and retained arboreal adaptations of the postcrania, suggests little change in the foraging strategies of the earliest hominids compared with their ape ancestors and further suggests similarity in evolutionary grade. This similarity may have extended to other aspects of behaviour, for example to patterns of tool making and use, which may have been similar in the common ancestor of apes and humans to the pattern shared by the earliest australopithecines and chimpanzees.

Squamous cell carcinoma of the scrotum: long-term followup of 14 patients

Squamous cell carcinoma of the scrotum was diagnosed in 14 patients from 1945 to 1990. Patient age at diagnosis ranged from 40 to 73 years, with the mean age of 62 years. The most common presentation was a solitary skin lesion but inguinal adenopathy was noted in 5 patients (36%). The mean delay to diagnosis for all patients was 22 months, with a range of 2 months to 10 years. Predisposing factors included psoriasis treated with coal tar or arsenic, human papillomavirus infection and multiple cutaneous epitheliomas. The primary lesion was treated by local or wide local excision in all 14 patients. In addition, 4 patients underwent inguinal lymphadenectomy and 3 underwent radiotherapy to the pelvic and inguinal lymph nodes. Mean followup for all patients was 6 years. However, 11 patients were disease-free with a mean followup of 7 years. Improved prognosis was noted in patients with locally confined disease or carcinoma in situ only. There was no correlation between grade of tumor and survival. All patients with stages A1 and B disease treated with wide local excision and/or inguinal lymphadenectomy have done well on followup. Radiotherapy does not appear to impact on survival for patients with high stage disease.

The large-scale isolation of bryostatin 1 from Bugula neritina following current good manufacturing practices

A novel process was designed for the large-scale isolation of bryostatin 1 from the bryozoan Bugula neritina L. in order to obtain multigram quantities of highly pure material for formulation studies, preclinical toxicology, and clinical trials in cancer patients. Multigram quantities of bryostatin 1 were obtained from a collection of approximately 10,000 gallons of wet animal. A phorbol dibutyrate (PDBu) receptor binding assay and hplc with photodiode array detection were used for the design, validation, and control of the isolation process.

Helicobacter pylori-negative duodenal ulcer

Most patients with chronic duodenal ulcer (DU) craters have gastritis associated with Helicobacter pylori (HP), now thought to be the major cause of DU. A smaller proportion of DU patients have no detectable HP. In this study, we examined the frequency and causes of HP-negative duodenal ulcers. In 302 consecutive patients with endoscopic diagnosis of duodenal ulcer, 284 (94%) were found to have associated HP gastritis, whereas 18 (6%) were HP-negative on histology, culture, and urease test. The largest subgroup of HP-negative patients (8/18) was made up of those who had been taking nonsteroidal antiinflammatory drugs (NSAIDs), followed closely (4/18) by patients with recent intake of antibiotics. Causes of DU in the remaining subgroups included two patients with duodenal Crohn's disease, two with Gastrospirillum hominis infection, one with penetrating carcinoma of the pancreas and one with no detectable cause. We conclude that, although the most common causal factor of duodenal ulcer is HP, some 6% of DU's will be HP-negative, signaling unusual etiology. It is now important to identify the cause of duodenal ulcer so as to initiate appropriate therapy.

Renal pelvic explosion during conservative management of upper tract urothelial cancer

Ureteroscopic fulguration of a renal pelvic papillary transitional cell carcinoma is a relatively new and limited procedure. We present a case of intrarenal explosion during ureteroscopic fulguration.

Hormonal regulation of prostate-specific antigen messenger RNA in human prostatic adenocarcinoma cell line LNCaP

Prostate-specific antigen (PSA) is a member of the kallikrein gene family and is expressed exclusively in human prostatic epithelial cells. PSA protein has been an important biological marker for prostate cancers. Until now, very little was known about the regulation of PSA expression in prostatic cells. In this study, we have developed a specific oligonucleotide probe which recognizes PSA but not the human glandular kallikrein. This is crucial because both PSA and human glandular kallikrein are expressed in the prostate at relatively high levels and have high nucleotide sequence homology (greater than 82%). Utilizing a S-labeled PSA-specific probe, PSA mRNA was localized within the glandular epithelium of the prostate. Northern blot analysis detected a single 1.6-kilobase transcript in LNCaP cells, a cell line derived from a human prostate adenocarcinoma metastasis. Therefore, LNCaP cells were used to study the androgenic effects on PSA mRNA expression. A time course study demonstrated that PSA mRNA was induced by mibolerone (a nonmetabolizable synthetic androgen) and reached maximal levels after 9 h. The induction of PSA mRNA required as little as 0.3 nM mibolerone. In addition to mibolerone, PSA mRNA could be induced by the natural androgen, dihydrotestosterone, but not by the synthetic glucocorticoid, dexamethasone, or the synthetic estrogen, diethylstilbestrol. Moreover, in the presence of dihydrotestosterone, PSA mRNA was depressed by hydroxyflutamide (an antiandrogen). These results suggest strongly that the androgenic effects on PSA mRNA in LNCaP cells may be via the function of the androgen receptor.

Minimum analogue peptide sets (MAPS) for quantitative structure-activity relationships

The information contents in previously published peptide sets was compared with smaller sets of peptides selected according to statistical designs. It was found that minimum analogue peptide sets (MAPS) constructed by factorial or fractional factorial designs in physiochemical properties contained substantial structure-activity information. Although five to six times smaller than the originally published peptide sets the MAPS resulted in QSAR models able to predict biological activity. The QSARs derived from a MAPS of nine dipeptides, and from a set of 58 dipeptides inhibiting angiotensin converting enzyme were compared and found to be of equal strength. Furthermore, for a set of bitter tasting dipeptides it was found that an incomplete MAPS of 10 dipeptides gave just as good a model as the model based on a set of 48 dipeptides. By comparison other non-designed sets of peptides gave QSARs with poor predictive power. It was also demonstrated how MAPS centered on a lead peptide can be constructed as to specifically explore the physiochemical and biological properties in the vicinity of the lead. It was concluded that small information-rich peptide sets MAPS can be constructed on the basis of statistical designs with principal properties of amino acids as design variables.

Cure of duodenal ulcer after eradication of Helicobacter pylori

Eighty-two patients, whose duodenal ulcers were recurrent or resistant to H2-receptor antagonist therapy, were entered in a treatment protocol of ranitidine followed by a four-week "triple therapy" course to eradicate Helicobacter pylori (HP) infection. The triple therapy consisted of colloidal bismuth subcitrate, tetracycline and metronidazole. Duodenal ulcer healed in all 78 patients available for endoscopy and H. pylori infection was shown to be eliminated in 75 patients (96%) at rebiopsy four weeks after cessation of therapy. In these 75 remaining patients the relapse rates for H. pylori infection and duodenal ulcer were studied endoscopically, yearly and at any recurrence of symptoms. At Year 1, 71 of 73 patients remained free of H. pylori infection (HP-negative) and duodenal ulcer. The corresponding figures subsequently were: Year 2, 57/57; Year 3, 34/34; Year 4, 15/15. No duodenal ulcers recurred in HP-negative patients who were followed for up to four years. Two patients of the original cohort of 75 HP-negative patients were HP-positive with endoscopic duodenitis at 12 months, and one at 36 months, but all were without reulceration. Distorted duodenal caps gradually returned to near-normal appearance in 80% of patients by two years. From this four-year follow-up study we conclude that duodenal ulcer disease will not recur provided the patient remains free of H. pylori.

Pregnancy Sickness

The majority of women suffer from nausea and vomiting in the first trimester of pregnancy, but the mechanisms and reasons for this are unknown. Based on our current understanding of the emetic response and physiological changes of early pregnancy, hypotheses are put forward to explain this apparently inappropriate response to conception.

Inhibition of lymphocyte circulation in mice by pertussis toxin

Pertussis toxin (PT), a protein toxin of Bordetella pertussis, also called pertussigen, has a wide range of biological activities, including the induction of lymphocytosis. This phenomenon was investigated by studying lymphocyte circulation in mice. Lymph node cell suspensions were exposed to PT in vitro and then injected intravenously. A double radiolabel technique was employed, in which PT-treated and control cells were injected into the same animals. The protocol used in these experiments was chosen to demonstrate a direct effect of PT on the injected cells. After exposure to PT in vitro, cells were profoundly excluded from lymph nodes over the succeeding six days. Entry into both mesenteric and peripheral lymph nodes, but not into the spleen was inhibited by PT, and there was an accumulation of the PT-treated cells in the blood. Cells were excluded from the lymph nodes after treatment with as little as 2 ng/mL of PT. This dose was over two orders of magnitude lower than the threshold dose of the same PT preparation required to induce lymphocyte mitogenesis in vitro. The findings in the present communication are consistent with studies using genetically modified PT in which the ADP-ribosylating capacity of the A-subunit was necessary for the effect of PT on lymphocytosis.

Geometries of functional group interactions in enzyme-ligand complexes: guides for receptor modelling

An approach is described which makes use of X-ray structural data from enzyme-ligand complexes in order to obtain information for application in receptor modelling. The atomic surroundings of five different ligand functional groups were determined for all complex structures recorded in the Brookhaven Protein Data Bank. These atomic surroundings were then superimposed with respect to the atoms of the functional groups of the ligands in order to obtain clouds of neighbouring atoms. General principles were sought to describe the orientation or favoured position of groups or atoms around those functional groups when bound to a macromolecule. Some simple conclusions and leads for further modelling were thus derived.

Morphological alterations of the glomerular (visceral) epithelium in response to pathological and experimental situations

The glomerular (visceral) layer of Bowman's capsule is comprised of a unique population of cells which have been termed "podocytes." Arising from these cells are large major processes and numerous smaller foot processes which completely surround underlying glomerular capillary loops. Podocyte foot processes interdigitate with each other and are separated by spaces (filtration slits) which are designed to facilitate flow of a large amount of filtrate across the glomerular wall. Podocytes exhibit dramatic morphological changes in response to the nephrotic syndrome and some forms of acute renal failure and may play an important role in the pathophysiology of these conditions. In vitro and in vivo studies have shown that a reduction in the sialic acid component of a thick anionic surface coat plays a major role in the morphological changes that these cells exhibit in the nephrotic syndrome. Also, it has been shown that filamentous actin concentrated mainly within podocyte foot processes are the contractile elements responsible for altering the shapes of these processes. There is evidence to suggest that by altering the shapes of their foot processes, podocytes in the normal kidney are able to alter the number of fully patent filtration slits and thereby actively regulate the rate of solute efflux across the glomerular wall. In vitro and in vivo studies have indicated that cytoplasmic microtubules are probably not involved in alterations of the podocyte foot processes but do appear important in maintaining the morphological integrity of podocyte cell bodies and their major processes. In the present paper, the morphological changes which glomerular podocytes exhibit in response to the nephrotic syndrome, various forms of acute renal failure, and during in vitro incubation are discussed along with studies of the possible roles of cytoplasmic microtubules, microtubules, and the glomerular anionic surface coat in these changes.