A cDNA encoding a nuclear hormone receptor of the steroid/thyroid hormone-receptor superfamily from the human parasitic nematode Strongyloides stercoralis

A cDNA encoding a nuclear hormone receptor of the steroid/thyroid receptor superfamily was obtained from third-stage larvae(L3) of the parasitic roundworm Strongyloides stercoralis. A recombinant clone was isolated via screening of an S. stercoralis cDNA library with a polymerase chain reaction (PCR)-generated probe. The insert of 2,583 bp contained the complete coding sequence of the receptor homologue. The conceptually translated amino acid sequence of this open reading frame encodes a 753-amino-acid-residue protein with an apparent molecular weight of 83.6 kDa and a predicted isoelectric point (pI) of 8.52. The coding sequence is 69% AT and the noncoding sequence is 72% AT, reflecting a characteristic A/T codon bias of S. stercoralis. In this report the amino acid sequence of the S. stercoralis nuclear hormone receptor of the steroid/thyroid receptor superfamily is compared with that of nuclear hormones of Caenorhabditis elegans, human orphan nuclear receptors, and insect ecdysone receptors. The potential role of steroids in the induction of hyperinfection syndrome is also discussed.

Interferon-alpha upregulates gene expression of aquaporin-5 in human parotid glands

Aquaporins are a family of homologous membrane proteins that function as highly selective water channels. Aquaporin-5 (AQP5) is uniquely present in lacrimal and salivary glands, where it accounts for normal tear and saliva production. We tested the hypothesis that orally administered human interferon-alpha (HuIFN-alpha) benefits persons with xerostomia by augmenting the production of AQP5 protein by parotid gland epithelium. Cells from three human parotid glands were cultured with and without human lymphoblastoid IFN-alpha, and assayed for AQP5 mRNA levels by reverse transcriptase polymerase chain reaction (RT-PCR), and AQP5 protein levels by Western blot. Intracellular localization of AQP5 protein was done using confocal microscopy. The functional integrity of the glandular tissue was confirmed by RT-PCR analysis of alpha-amylase 1 and basic proline-rich protein transcripts. AQP5 was constitutively expressed in human parotid gland tissue, with AQP5 protein restricted to the plasma membranes and cytoplasmic vesicles of acinar cells. IFN-alpha augmented AQP5 transcription and protein production in a concentration-dependent manner, and increased the size of intensity of staining of AQP5-containing cytoplasmic vesicles in acinar cells. We conclude that IFN-alpha upregulates AQP5 gene expression in human parotid acinar cells in vitro. To our knowledge, this is the first demonstration that IFN-alpha regulates the gene expression of an aquaporin.

Oral use of interferon-alpha stimulates ISG-15 transcription and production by human buccal epithelial cells

ISG-15 is a 15-kDa protein encoded by an interferon (IFN)-stimulated gene (ISG), which is transcriptionally regulated by IFN-alpha and IFN-beta. Considered as part of the cytokine network, ISG-15 has the potential to amplify the immunomodulatory effects of these IFNs by enhancing IFN-gamma production, natural killer cell proliferation, and lymphokine-alphactivated killer cell cytotoxicity. To understand better the mechanism(s) of action of orally administered IFN-alpha, we have studied the effect of IFN-alpha on ISG-15 gene expression by human buccal epithelial cells (BEC). For in vitro studies, ISG-15 mRNA and protein levels were measured in BEC incubated for 0.5, 2, and 9 h with 100 or 1,000 IU/ml of human lymphoblastoid IFN-alpha. For in vivo studies, ISG-15 mRNA was measured in BEC samples collected at baseline, and 0.5, 2, and 9 h after 5-20 min of oral rinsing with 10 ml of IFN-alpha (1,000 IU/ml). ISG-15 mRNA was measured by reverse transcriptase polymerase chain reaction (RT-PCR), and ISG-15 protein production by Western Blot analysis. IFN-alpha augmented BEC ISG-15 gene expression in a concentration dependent manner both in vivo and in vitro. We conclude that orally administered IFN-alpha exerts its immunomodulatory effects in humans in part by upregulating the production of ISG-15 by BEC, thereby enhancing the immune reactivity of mucosa-associated lymphocytes.

Proteins in renal stones and urine of stone formers

Knowledge of the essential characteristics of macromolecules constituting the organic matrix of the nidus of urinary stones is required to understand the mechanism of urolithogenesis. The aim of this study was to isolate and characterise those stone nidus proteins. Using an extraction buffer containing SDS and beta-mercaptoethanol, we were able to overcome known problems of protein isolation from urinary stone matrix. These proteins were characterised by a strong tendency to aggregate under reducing and denaturing conditions. On SDS-PAGE, their molecular weights range from < or = 12 to 66 kDa. Antisera raised against stone matrix proteins showed a cross-reactivity between proteins isolated from different stones irrespective of their origin or mineral composition. Moreover, urinary proteins from stone formers also cross-reacted with these whereas there was no reaction with urinary proteins of non-stone formers. Western blotting confirmed these findings. Given the above summarised properties, it can be safely concluded that these proteins are prevalent in urines of stone formers, that they are selectively incorporated into renal stones of all aetiologies, and that they most likely have a role in nidus and, therefore, early stone formation.

Risk of transmission and features of hepatitis C after needlestick injuries

The rate of transmission and management of needlestick injuries from hepatitis C virus (HCV) patients to healthcare workers is still a matter of debate. We used a stringent protocol using monthly transaminase levels and polymerase chain reaction for HCV RNA to monitor 53 healthcare workers prospectively for up to 6 months following needle injuries from HCV-positive patients. Evidence of transmission of HCV was found in only 2 workers (4%) with mild asymptomatic infection, one of which resolved spontaneously. Based on our experience, we now use a less-intensive follow-up protocol. Further investigation is required to determine the most cost-effective method to monitor individuals who suffer a needlestick injury from an HCV-positive patient.

Evidence for a high affinity, saturable, prenylation-dependent p21Ha-ras binding site in plasma membranes

Oncogenic p21ras proteins can only exert their stimulation of cellular proliferation when plasma membrane-associated. This membrane association has an absolute requirement for post-translational modification with isoprenoids. The mechanism by which isoprenoids participate in the specific association of p21ras with plasma membranes is the subject of this report. We present in vitro evidence for a plasma membrane binding protein for p21(ras) that can recognize the isoprenoid substituent and, therefore, may facilitate the localization of p21ras.

Protection against Schistosoma mansoni infection with a recombinant baculovirus-expressed subunit of calpain

Infections by human schistosomes, in particular Schistosoma mansoni, account for significant morbidity and mortality every year in tropical and sub-tropical areas. The eggs of the parasite induce pathological changes in the infected host; in chronic and heavy infections, these changes may lead to death. A well-designed anti-schistosomal vaccine, alone or in concert with existing control measures such as chemotherapy, may prove to be a safe, inexpensive, and effective means of reducing the occurrence of severe disease and death in S. mansoni infection. Previous studies have demonstrated the importance of the syncytial layer containing the apical plasma membrane (APM) of S. mansoni in both the survival of the parasite in the mammalian host and as a potential source of immunogens which may be utilized as vaccine candidates. In this paper, we present evidence for the protective capacity of several schistosomal antigen preparations, including a calcium binding protein of the APM, S. mansoni calpain (GenBank accession no. M74233). We have constructed and characterized expression of a recombinant baculovirus expressing the large subunit of S. mansoni calpain, Sm-p80. This recombinant Sm-p80 is recognized by IgA, IgM, IgG1, and IgG3 isotype antibodies found in S. mansoni-infected human sera and partially-purified recombinant Sm-p80 provided a 29-39% reduction in worm burden in immunized mice challenged with S. mansoni. Our data indicate that Sm-p80 may be a useful vaccine antigen for the reduction of the morbidity associated with S. mansoni infections of mammalian hosts.

Genetic markers and duodenal ulcer

Serum pepsinogen, alpha 1-antitrypsin (alpha 1-AT) and blood groups were studied as genetic markers in 32 patients with endoscopically proven duodenal ulcer and 44 control subjects with no family history of ulcer disease. Serum pepsinogen was determined by the modified method of Edward et al, alpha 1-AT by single radial immunodiffusion (RID) and phenotyping was carried out by isoelectric focusing (IEF). Duodenal ulcer patients with hyper- pepsinogenemia (28%) and low serum alpha 1-AT (35%) had a dominant blood group O, lower mean age, an early onset of disease, a higher frequency of gastrointestinal (GI) bleeding and ulcer perforation. These parameters were found considerably different in patients with normal serum pepsinogen and alpha 1-AT. Phenotype analysis of alpha 1-AT revealed that four duodenal ulcer patients had partial deficiency of the protease inhibitor and none of the normal exhibited the deficiency pattern. The etiology of the disease appears to be genetic anomaly in 28% of patients while the rest (72%) had ulcers as a result of neuroendocrinological or environmental factors.

Strongyloides stercoralis: identification of antigens in natural human infections from endemic areas of the United States

Using Western-blot analysis, we identified eight immunodominant antigens (apparent molecular weights 96, 86, 75, 56, 41, 32, 28, and 26 kDa) of Strongyloides stercoralis in natural human infections. For this study, 78 individual serum samples were obtained from S. stercoralis-infected patients residing in endemic areas of the United States. Poly A+ RNA was translated in vitro in the rabbit-reticulocyte lysate system. The newly synthesized translation products were immuno-precipitated with S. stercoralis human infection sera. All eight of the identified antigens were detected in the immunoprecipitates. The potential of these antigens as targets for immunodiagnosis is also discussed.

An evaluation of a dentifrice containing salivary peroxidase elements for the control of gingival disease in patients with irradiated head and neck cancer

Patients who have undergone irradiation for head and neck tumors commonly have xerostomia. Loss of the protective constituents normally found in saliva leaves patients at greater risk for development of significant dental pathologic disorders, including gingival and periodontal disease. Periodontal disease and tooth extractions are currently accepted as etiologic factors for the development of osteoradionecrosis. This double-blind crossover trial was conducted to assess the efficacy of a dentifrice containing salivary peroxidase elements in the reduction of gingivitis in a population of patients with irradiated cancer. Subjects were instructed to brush with the dentifrice provided. Plaque and gingival index values were obtained and statistically compared with baseline values. A weak positive effect was found between use of the dentifrice and a reduction in gingival inflammation. Patient compliance was a limiting factor in this treatment effect. The results suggest possible efficacy for the dentifrice in augmenting traditional measures of postradiation oral health maintenance.

Open drainage of massive tuberculous empyema with progressive reexpansion of the lung: an old concept revisited

BACKGROUND

This study examined the results of open drainage of massive tuberculous empyema.

METHODS

During a 7-year period 47 patients with primary mixed chronic tuberculous empyema with near or total lung collapse were treated. The initial procedure was chest tube suction drainage, which permitted evaluation of the pleural cavity and the lung parenchyma despite minimal if any reexpansion of the lung. All patients were treated with antibiotics and multidrug regimens of antituberculosis agents. A pleurocutaneous window was established by removing sections of two ribs one intercostal space above the base of the pleural cavity. Irrigation was performed daily with dilute povidone iodine solution.

RESULTS

Twenty-eight patients achieved complete reexpansion of the lung after 4 to 30 months of drainage and are cured. Eleven are in various stages of reexpansion and probably will be cured. Eight patients did not achieve reexpansion. Criteria were established retrospectively on an ongoing basis that indicate when pulmonary reexpansion is possible.

CONCLUSIONS

These totally collapsed "entrapped" lungs expanded to fill the entire pleural space despite the presence of bronchopleural fistulas and an "open" pleura. Reexpansion was progressive, gradual, and dependent on improved compliance, clearing of bronchial inflammation and obstruction, and pleural cleansing. Criteria are established that identify those patients in whom complete reexpansion may take place and the disease may be cured.

Serum alpha 1 antitrypsin and pulmonary emphysema

Using isoelectric focusing (IEF) and radial immunodiffusion (RID) techniques, serum samples from 100 normal healthy adults and 21 patients with pulmonary emphysema were analysed to identify various alpha 1 antitrypsin phenotypes and the serum concentrations. Ten percent of the patients had low serum values. The normal or most common genetic form, MM, is the predominant phenotype in both controls and patients.

Retrospective multicenter analysis of 3i endosseous dental implants placed over a five-year period

Osseointegrated dental implants have now become an accepted form of treatment for patients with a fully or partially missing dentition. The purpose of this study was to evaluate the performance of 3i threaded and cylindrical implants. During a 5-year period, a total of 1969 3i endosseous implants were placed at 6 centers in the United States and 2 elsewhere in the edentulous and partially edentulous jaws of 653 consecutive patients ranging in age from 18 to 82 years. Of the total number of implants placed, 1341 were commercially pure titanium threaded implants and 628 were titanium plasma-sprayed implants with a cylindrical configuration. A total of 28 patients with 110 implants were lost to follow-up. Implants in these patients were considered neither a success nor a failure. Success was predicated on the osseointegration of each and every implant followed in this analysis rather than the persistence of prosthetic function. Confirmed bone anchorage was considered essential for success. A total of 625 patients with 1871 implants remain in the study with a follow-up period ranging from 6 to 60 months. A total of 93 implants (5.0% of the total implants followed) were considered as failures. A mean implant survival rate was 95.0% for both the threaded and the cylindrical implant was calculated. The success rate of threaded implants was 97.0% in the mandible and 93.8% in the maxilla. The success rate for the 3.3-mm cylindrical implants was 96.0% in the mandible and 95.5% in the maxilla, and the success rate of 4.0-mm-diameter cylindrical implants was 95% in the mandible and 92.0% in the maxilla. Causes of failure consisted of loss of osseointegration (2.3%), crestal bone loss requiring periodontal therapy after the first year of function (1.7%) had mechanical problems associated with the prosthesis (0.9%). This retrospective analysis of the 3i endosseous implant system is comparable to previous reports on other implant systems in terms of implant survival and prosthesis stability. It is demonstrated that 3i implants are predictable and can provide lasting osseointegration leading to improvement of oral function if the recommended surgical and restorative protocol is followed.

Genetic variants of serum alpha 1 antitrypsin

Complete absence of data on alpha 1 antitrypsin in this country prompted us to determine serum levels using radial immunodiffusion (RID) and phenotypes by isoelectric focusing (IEF) in 100 healthy adults (52 males and 48 females). Mean serum alpha 1 antitrypsin concentration in healthy subjects was 2.47 +/- 0.08 g/l and the main phenotypes MM (70%), M1 M2 (28%) and FM 3 (2%) are infrequent in our population.

Use of an optical comparator for radiographic measurement of bone loss around endosseous implants: a pilot study

A technique for the measurement of bone loss around endosseous implants using an optical comparator was investigated. Five operators were asked to measure the mesial and distal alveolar bone levels around a screw type dental implant on a periapical radiograph mounted on an optical comparator. The known size of a threaded implant was used as a reference. The bone loss around the implant was calculated by taking the average of the mesial and distal measurements. Statistical analysis at the 95 percent confidence level demonstrated that there was no significant difference among the measurements. Although the initial results are encouraging, additional research is necessary with a larger sample size to validate the accuracy of optical comparator readings and compare the efficacy of this technique with other currently used methods for determining bone loss around root form implants.

A four-year retrospective study of 3i threaded implants

The use of osseointegrated implants can be considered as one of the most productive developments in dentistry during this century. Although initially introduced for use in fully edentulous patients, their present widespread use in nearly all forms of tooth loss, as well as for the rehabilitation of maxillofacial prosthetics and in orthodontics, has significantly expanded the realm of restorative dentistry. The present multicentre retrospective study evaluates the results of 327 patients rehabilitated with 1047, 3i (Implant Innovations Inc.) threaded implants over a four-year period. Eight patients with 22 implants dropped out and were excluded from the study as they could not be evaluated. A total of 319 patients with 1025 implants remained. Nine implants failed in the mandible and 14 in the maxilla. There was a success rate of 98.2 percent in the mandible and 97.3 percent in the maxilla. The mean overall success rate was 97.75 percent, with little variation between the four study centres. These results are similar to previously published studies on titanium threaded implants and indicate that, with careful adherence to accepted principles of surgery and restorative dentistry, the 3i threaded implant system can be used confidently to provide the necessary support for an osseointegrated implant-supported prosthesis.

Disposable trays for complete denture construction: a dimensional study of a type frequently used in the UK and of its suitability for the edentulous population

This study compares the sizes of patients' edentulous arches with the shapes of a range of disposable stock trays from one manufacturer. In many dimensions there is considerable discrepancy between the two. It is concluded that, even with tray modification, it is almost impossible to obtain an accurate impression of the shape of the all-important sulcus regions. Such a conclusion emphasises the importance of obtaining further impressions in special trays which are modified appropriately.

Serum alpha 1-antitrypsin and duodenal ulcer

Evaluation of serum alpha 1-antitrypsin levels in the South Asian population and its possible involvement in disease conditions such as duodenal ulcer has not been given due consideration. This is mainly because reports from European and North American countries indicate that the genetic deficiency of this protease inhibitor is rare among Asians of the subcontinent. Using isoelectric focusing (IEF) and radial immunodiffusion (RID) techniques, we analysed serum samples from 100 normal, healthy adults and 50 patients with endoscopically proven duodenal ulcers to determine if there is a possible relationship between alpha 1-antitrypsin phenotype and this disease. Five duodenal ulcer patients had low alpha 1-antitrypsin levels as well as SZ and S phenotype. None of the controls showed presence of S or SZ phenotypes. The normal or most common genetic form, MM, is the predominant phenotype in both controls and patients.

Characterization of Ca(2+)-dependent neutral protease (calpain) from human blood flukes, Schistosoma mansoni

Calcium-dependent, neutral cysteine-proteases (calpain) were purified from human blood flukes, Schistosoma mansoni. The electrophoretic mobilities, Western blot analyses and high specificity to peptide inhibitors confirmed the presence of both calpain I and II in the purified preparation. The schistosome calpains were localized in the surface syncytial epithelium and underlying musculature. Using peptide inhibitors, calpain was shown to function as a mediator of the surface membrane synthetic process. Since there was also no immunological cross-reactivity between vertebrate and schistosome calpains using antibodies affinity-purified from native and recombinant schistosome calpains, this protease may be usefully investigated as forming the basis of a molecular vaccine against schistosomiasis.