A quantitative analysis of symptoms of non-ulcer dyspepsia as related to age, pathology, and Helicobacter infection

BACKGROUND

Non-ulcer dyspepsia (NUD) has been attributed to gastritis and Helicobacter infection. The Sydney classification enables dyspepsia symptoms to be assessed quantitatively in relation to Helicobacter infection and topographic pathology in different gastric compartments.

METHODS

In this study of 348 patients with NUD we studied the unconfounded effects of age, pathology, and Helicobacter. Endoscopic findings, dyspeptic symptoms, and age were recorded prospectively. Multiple logistic regression was used to evaluate the independent effects of age, pathology, and Helicobacter.

RESULTS

Ulcer-like pain was negatively related to age (odds ratio = 0.75/10 years; P < 0.001). A high density of Helicobacter at the antrum but not elsewhere in the stomach was positively related to ulcer-like pain (odds ratio = 3.38; P < 0.002). Adjusted for age, none of the endoscopic (P > 0.19) and histopathology findings (P > 0.09) played an important role in NUD.

CONCLUSION

Age was the most important determinant of dyspeptic symptoms, but not pathology or Helicobacter.

Effectiveness of a continuous quality improvement program aiming to reduce unplanned extubation: a prospective study

OBJECTIVE

To evaluate the effectiveness of a continuous quality improvement (CQI) program in reducing the incidence of unplanned endotracheal extubation.

DESIGN

Prospective study over a 9-month period.

SETTING

Adult intensive care units (ICUs including coronary care unit, medical ICU, surgical ICU, and cardiovascular surgical ICU) in a university-affiliated medical center.

PATIENTS

831 consecutive mechanically ventilated patients.

INTERVENTIONS

CQI program focusing on standardization of procedures, improvement of communication, and identification and management of high-risk patients.

MEASUREMENTS AND RESULTS

With the implementation of this CQI program, the overall incidence density of unplanned extubation (defined as number of new unplanned extubations per mechanical ventilation patient-days) significantly decreased from 2.6% in the first trimester to 1.5% in the second trimester and 1.2% in the third trimester (p = 0.01). This reduction was essentially the result of a decrease in unplanned extubation in orally intubated patients (incidence density 4.6, 1.7 and 1.0% for three trimesters, respectively; p < 0.0001). Unplanned extubation in nasally intubated patients remained largely unaffected (1.2, 1.4, and 1.4% for three trimesters, respectively; p = 0.92).

CONCLUSIONS

The implementation of a concerted CQI program is effective in reducing the overall incidence of unplanned endotracheal extubation.

Profound hypothermia and cardiopulmonary bypass in the treatment of recurrent giant angioblastic meningioma case report

Hypothermia and cardiopulmonary bypass has rarely been used for difficult lesions of the brain such as giant aneurysms and hemangioblastoma of the brainstem. We report a case of huge recurrent angioblastic meningioma operated under the profound hypothermia and cardiopulmonary bypass. We reviewed the complications related to hypothermia and cardiopulmonary bypass for brain lesions.

Monovalent cation transport: lack of structural deformation upon cation binding

Cations often deform the structure of regulatory proteins to affect a functional response, but for other protein functions a more passive effect is desired. For instance, it is shown here that in the conductance of Na+ by the gramicidin channel there appears to be no significant structural deformation of either the side chains or backbone upon Na+ binding in the channel. This is based on 15N and 13C chemical shifts, 2H quadrupolar interactions, and 15N-2H dipolar interactions obtained by solid-state NMR spectroscopy of uniformly aligned lipid bilayer preparations of the gramicidin channel in the presence and absence of Na+. This conclusion is despite some significant changes in the 15N alpha and 13C1 chemical shift values which are argued here to be the result of indirect polarization effects upon cation binding rather than reflections of structural and dynamic changes. The lack of structural deformation implies that Na+ moves to the carbonyl oxygens lining the pore of this channel for solvation rather than the carbonyl groups moving in toward the channel axis. This forces the cations onto a helical path following the positions of the carbonyl oxygens around the channel pore. Furthermore, an ideal binding site geometry for Na+ in the channel is avoided. Instead, adequate binding energy is provided by the channel to compensate for the loss of hydration energy when the cations enter the channel. The avoidance of strong binding ensures that efficient transport of the cations through the channel can be realized.

Ligand-dependent conformational plasticity of the periplasmic histidine-binding protein HisJ. Involvement in transport specificity

The periplasmic histidine permease of Salmonella typhimurium is composed of a membrane-bound complex and a soluble histidine-binding protein (the periplasmic receptor), HisJ. Liganded receptor interacts with the membrane-bound complex, inducing ATP hydrolysis and substrate translocation. Preliminary evidence had shown a lack of direct correlation between the affinity of HisJ for a ligand and translocation efficiency, suggesting that the precise form of the receptor is important in determining its interaction with the membrane-bound complex. We have investigated the nature of the conformations assumed by HisJ upon binding a variety of ligands by tryptophan fluorescence enhancement, reaction with a closed form-specific monoclonal antibody, and changes in UV absorption spectra. It is demonstrated that although HisJ binds all the ligands and undergoes a conformational change, it assumes measurably different conformations. We also show that the interaction between HisJ and the membrane-bound complex depends on the nature of the ligand. Transport specificity appears to be defined, at least in part, by the conformation of the bound receptor, manifested either by the effect of a given ligand on the closed structure per se, or by the effect of ligand association on the equilibrium constant relating the open and the closed liganded forms.

Heparinase I (neutralase) reversal of systemic anticoagulation

BACKGROUND

Protamine causes multiple adverse reactions. Heparinase I, a specific enzyme that inactivates heparin, is a possible alternative to protamine. In this study, the authors examined the efficacy of heparinase I to reverse heparin-induced anticoagulation in vitro and compared heparinase I to protamine as an antagonist of heparin-induced anticoagulation in dogs.

METHODS

In the in vitro study, blood was obtained from the extracorporeal circuits of 12 patients, and activated clotting times were determined after adding different concentrations of heparinase I. In the in vivo study, 24 anesthetized dogs received 300 units/kg heparin injected intravenously for 5 s, then 10 min later, 3.9 mg/kg protamine, 5-41 micrograms/kg heparinase I, or the vehicle (n = 4/group) were administered intravenously, and activated clotting times and hemodynamics were measured.

RESULTS

In the in vitro study, heparin concentrations of 3.3 +/- 1.0 (mean +/- SD) units/ml (approximately 0.033 mg/ml; n = 12) were reversed in the blood of patients by heparinase I at concentrations > 0.490 microgram/ml. In the canine study, heparinase at all doses studied and protamine effectively reversed the anticoagulating effects of heparin within 10 min of administration. Protamine produced adverse hemodynamic effects, whereas heparinase or its vehicle produced no significant change in arterial pressure.

CONCLUSION

Both heparinase I and protamine effectively reversed heparin anticoagulation. However, as opposed to protamine, heparinase I did not produce any significant hemodynamic changes when given as a bolus to dogs.

Association of self-limited cytomegalovirus colitis and shigellosis in an immunocompetent patient

Cytomegalovirus (CMV) infection of the colon has been rarely reported in immunocompetent patients. Patients with severe acute illness or disseminated CMV infection have high mortality. In contrast, the patients with local injury of the colon due either to other gastrointestinal infections or to anal intercourse, who are otherwise healthy, usually have self-limited disease. The CMV infection is believed to be the bystander and may be treated conservatively. Concomitant CMV colitis and other gastrointestinal infections occur exclusively in immunosuppressed patients. We report, to our knowledge, the first case of co-infection of the colon with CMV and Shigella in an immunocompetent patient. The hypothesis is that the mucosal damage caused by Shigella infection may predispose the colon to secondary CMV invasion.

Macromolecular structural elucidation with solid-state NMR-derived orientational constraints

The complete structure determination of a polypeptide in a lipid bilayer environment is demonstrated built solely upon orientational constraints derived from solid-state NMR observations. Such constraints are obtained from isotopically labeled samples uniformly aligned with respect to the B(0) field. Each observation constrains the molecular frame with respect to B(0) and the bilayer normal, which are arranged to be parallel. These constraints are not only very precise ( a few tenths of a degree), but also very accurate. This is clearly demonstrated as the backbone structure is assembled sequentially and the i to i + 6 hydrogen bonds in this structure of the gramicidin channel are shown on average to be within 0.5 A of ideal geometry. Similarly, the side chains are assembled independently and in a radial direction from the backbone. The lack of considerable atomic overlap between side chains also demonstrates the accuracy of the constraints. Through this complete structure, solid-state NMR is demonstrated as an approach for determining three-dimensional macromolecular structure.

Conformational trapping in a membrane environment: a regulatory mechanism for protein activity?

Functional regulation of proteins is central to living organisms. Here it is shown that a nonfunctional conformational state of a polypeptide can be kinetically trapped in a lipid bilayer environment. This state is a metastable structure that is stable for weeks just above the phase transition temperature of the lipid. When the samples are incubated for several days at 68 degrees C, 50% of the trapped conformation converts to the minimum-energy functional state. This result suggests the possibility that another mechanism for functional regulation of protein activity may be available for membrane proteins: that cells may insert proteins into membranes in inactive states pending the biological demand for protein function.

Chromoblastomycosis: a retrospective study of six cases at the Royal Darwin Hospital from 1989 to 1994

Chromoblastomycosis, a localized chronic cutaneous and subcutaneous infection of the skin caused by pigmented fungi, is most common in the world's tropical and subtropical zones. The condition rarely occurs in Australia. We present 6 cases of chromoblastomycosis seen at the Royal Darwin Hospital, Northern Territory, from 1989 to 1994 and affecting predominantly male Caucasians ranging from 38 to 71 yrs of age. Clinically the lesions were verrucous or nodular. They mimicked basal or squamous cell carcinoma, nevi or solar keratoses. Histopathologic findings were nonspecific. The only pathognomonic finding was the presence of brown spores or sclerotic bodies within granulomata or within microabscesses in the skin.

False localization of rupture by computed tomography in bilateral internal carotid artery aneurysms

BACKGROUND

Focal clot on computed tomographic (CT) scan is one of the most reliable clues in determining the site of rupture in patients with multiple intracranial aneurysms. However, unusual presentation of clot may cause false localization of the ruptured aneurysm in bilateral aneurysms, particularly when they are located near the midline.

METHODS

We describe two cases of bilateral internal carotid artery (ICA) aneurysms presenting contralateral distribution of clot on CT scan.

RESULTS

Misjudgment of rupture site by the CT scan resulted in clipping of the wrong aneurysm in one patient. Disastrous rebleeding occurred before the second operation for the ruptured one. In the other patient, the rupture site was assumed correctly despite contralateral situation of clot on CT, and both aneurysms were treated in one operative session.

CONCLUSIONS

Adhesion and obliteration of the subarachnoid cisterns from previous hemorrhage will deviate the direction of hemorrhage and present contralateral clot on CT scan in bilateral aneurysms located near the midline as ICA aneurysms. Medial direction of rupture may obscure accurate localization of rupture side in such aneurysms.

Analysis of 69 patients with amebic liver abscess

All 69 patients with amebic liver abscess that we treated in 1981-1992 were studied retrospectively. Men predominated by a 10:1 ratio. Of our 227 patients with amebiasis, some 30% yearly had liver involvement. The incidence peaked in 1988, decreasing later but increasing again in 1992. Most patients were 30-50 years old, the overall mean age being 45 years (range, 22-79), and decreasing with time. Patients with the related factors of travel abroad, positive results of a test for Treponema pallidum hemagglutination, and homosexuality have increased in number in recent years. Fever, abdominal pain, and hepatomegaly were the most frequent findings, and 39 patients had neither bloody stools nor diarrhea. Only 8 patients had had amebiasis previously. A solitary abscess in the right lobe of the liver was found in 40 patients. Entamoeba histolytica was found in the stool of 31 patients and in the pus of 39 patients. Sixty-one patients had positive results for an amebic serological test(s). The abscesses ruptured into the peritoneal cavity in 4 patients. All patients received metronidazole. Percutaneous or surgical drainage (or both) was done in 62 patients. The outcome was good, with 1 exception, and only 2 patients had recurrences.

Tubular adenosis of the breast. A distinctive benign lesion mimicking invasive carcinoma

Tubular adenosis, a term first coined by Oberman, is an uncommon benign lesion of the breast that may mimic invasive carcinoma. There is no formal description of this condition in the literature. We report the findings on six specimens from five patients (one with bilateral disease), including three that showed cancerization by intraductal carcinoma (DCIS). The ages of the patients ranged from 40 to 82 years. One patient presented with a 3-cm breast mass, and the others were found in specimens resected for infiltrating ductal carcinoma (two specimens) or DCIS (three specimens). The histologic hallmark of tubular adenosis was haphazard proliferation of elongated tubules that were noncrowded, narrow, and sometimes branching. There was no lobular arrangement or, at most, vague lobular grouping, with some tubules often extending into the fat. The tubules contained basophilic or granular eosinophilic secretion. The stroma was sclerotic to edematous. The tubules were lined by bland-looking ductal cells and were surrounded by an intact myoepithelial layer, a phenomenon well highlighted by immunostaining for muscle-specific actin (HHF-35) or S-100 protein. In three specimens, the tubular adenosis was cancerized by noncomedo DCIS, producing a pattern strongly mimicking infiltrating carcinoma; the in situ nature of the carcinoma was confirmed by actin immunoreactivity in the residual myoepithelium as well as by the presence of architecturally similar tubular adenosis in the vicinity. Tubular adenosis shows an infiltrative growth similar to microglandular adenosis and adenomyoepithelial adenosis, but it differs from them by the interdigitating tubular configuration and also differs from microglandular adenosis by the presence of myoepithelium. Tubular adenosis can be distinguished from sclerosing adenosis by the lack of obvious lobular architecture or whorled arrangement and wider separation of the tubules. Tubular adenosis appears to be a benign lesion per se, but whether it has premalignant potential remains to be determined. The importance of recognizing this entity lies in its being potentially mistaken for invasive carcinoma, especially at intraoperative frozen section or when the lesion is cancerized by DCIS.

The imaging diagnosis of hepatic schistosomiasis japonicum sequelae

We reviewed the ultrasound (US) and computed tomography (CT) examinations of the liver in 21 patients with hepatic schistosomiasis japonicum (HSJ), to assess the role of imaging in its diagnosis. Thirteen patients had histopathological evidence of hepatic ova deposition. A 'network' pattern was present in 14 of 17 (82%) patients on US, and 'turtle-back' calcification in 11 of 13 (85%) patients on non-contrast CT (NCCT). The combination of US and NCCT was positive for HSJ in all nine patients subjected to both investigations. These findings are specific for HSJ and we discuss how they differ from the imaging findings reported in hepatic Schistosoma mansoni (HSM). We conclude that the sequelae of HSJ infection create an imaging diagnosis. Although an uncommon incidental finding at liver imaging, the combined US and CT appearances are so characteristic that in the majority of patients biopsy can potentially be avoided.

Preliminary experiences with intraoperative radiation therapy (IORT) for the treatment of brain tumors

Ten brain tumor patients underwent wide resection of the tumor followed by Intraoperative Radiation Therapy (IORT) at the first surgery or at the second salvage surgery after failure of conventional external beam irradiation. Two patients(1 meningioma, 1 glioblastoma multiforme) were treated at the first surgery and 8 patients(3 anaplastic astrocytoma, 3 glioblastoma multiforme, 1 meningioma, 1 gliosarcoma) were treated after salvage surgery. The IORT doses were ranged from 15-25 Gy depending on the tumor volume and previous radiation therapy. The neurological status(Karnofsky performance status) was improved in 4 cases, not changed in 6 cases after IORT. There were several complications after IORT; radiation necrosis, communicating hydrocephalus, wound infection, and abnormal CT findings such as diffuse low density area in an around operation site. The radiation necrosis was confirmed by operation in a recurrent meningioma patient 12 months after IORT. At follow-up, ranging from 1 to 16 months, there was no deaths. Based on our limited experiences, the IORT might be one of the adjuvant therapeutic modalities especially for the malignant brain tumors and unresectable huge meningioma.

Attitudes, Knowledge, and Practices of Otolaryngologists Treating Patients Infected with HIV

The AIDS epidemic has become one of the most important public health problems of this century. As the prevalence of HIV infection continues to rise, health care practitioners in all geographic regions can expect greater clinical exposure to patients infected with HIV. We conducted an anonymous survey of all practicing otolaryngologists in Ohio and California to investigate regional differences in attitudes, knowledge, and practices regarding the care of patients infected with HIV. We also examined the data with respect to year of completion of residency training to identify differences in attitudes or practices among otolaryngologists who trained in the era of AIDS (post-1982 graduates) in comparison with their predecessors (pre-1982 graduates). In comparison with Ohio otolaryngologists, California otolaryngologists reported more frequent clinical encounters with HIV-infected patients and displayed significantly better knowledge regarding the otolaryngologic aspects of HIV infection. Californians were more likely to support the right of an HIV-infected physician to maintain an unrestricted practice and would be less likely to disclose their HIV status to their patients and hospital if they were to become infected with HIV. Post-1982 graduates had more frequent encounters with HIV-infected patients than did pre-1982 graduates and demonstrated a better fund of knowledge. Although Californians were more likely than Ohioans to routinely double glove in surgery, the overall double gloving rate was low at 21%. Californians were no more likely than Ohioans to routinely use protective eyewear, water-impervious gowns, or indirect instrument-passing techniques in surgery. No differences were observed in prevalence of protective surgical precautions between pre-1982 and post-1982 graduates. The results of the survey indicate a need for broader acceptance and use of “universal” surgical precautions among otolaryngologists.

Attitudes, knowledge, and practices of otolaryngologists treating patients infected with HIV

The AIDS epidemic has become one of the most important public health problems of this century. As the prevalence of HIV infection continues to rise, health care practitioners in all geographic regions can expect greater clinical exposure to patients infected with HIV. We conducted an anonymous survey of all practicing otolaryngologists in Ohio and California to investigate regional differences in attitudes, knowledge, and practices regarding the care of patients infected with HIV. We also examined the data with respect to year of completion of residency training to identify differences in attitudes or practices among otolaryngologists who trained in the era of AIDS (post-1982 graduates) in comparison with their predecessors (pre-1982 graduates). In comparison with Ohio otolaryngologists, California otolaryngologists reported more frequent clinical encounters with HIV-infected patients and displayed significantly better knowledge regarding the otolaryngologic aspects of HIV infection. Californians were more likely to support the right of an HIV-infected physician to maintain an unrestricted practice and would be less likely to disclose their HIV status to their patients and hospital if they were to become infected with HIV. Post-1982 graduates had more frequent encounters with HIV-infected patients than did pre-1982 graduates and demonstrated a better fund of knowledge. Although Californians were more likely than Ohioans to routinely double glove in surgery, the overall double gloving rate was low at 21%. Californians were no more likely than Ohioans to routinely use protective eyewear, water-impervious gowns, or indirect instrument-passing techniques in surgery. No differences were observed in prevalence of protective surgical precautions between pre-1982 and post-1982 graduates.(ABSTRACT TRUNCATED AT 250 WORDS)

Reversed-phase high-performance liquid chromatography of salmon calcitonin and its degradation products in biological samples using column switching and flow-through radioisotope detection

For the determination of salmon calcitonin and its degradation products in biological samples, a reversed-phase HPLC method with column switching and flow-through radioisotope detection has been developed using high specific activity [125I]salmon calcitonin. Effects of the precolumn packing material and washing solvent were examined in terms of [125I]salmon calcitonin recovery. Spiked samples of [125I]salmon calcitonin in plasma and kidney homogenate were injected onto a LiChroprep RP-8 precolumn after dilution with 0.1% trifluoroacetic acid. After washing the polar interfering compounds with 0.1% trifluoroacetic acid, the concentrated [125I]salmon calcitonin and its degradation products were eluted and separated on a W-Porex C18 column with a gradient of 0.1% trifluoroacetic acid in acetonitrile-water. Detection and calibration of [125I]salmon calcitonin were possible down to picogram levels. Reproducible kinetic data for the degradation of intact [125I]salmon calcitonin were possible down to picogram levels. Reproducible kinetic data for the degradation of intact [125I]salmon calcitonin by rat kidney homogenate could be traced.

Relationship between tissue plasminogen activator, plasminogen activator inhibitor and CT image in chronic subdural hematoma

The present study was performed to investigate the relationship between the concentrations of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) and the CT images in 23 cases of chronic subdural hematomas (SDHs). The concentrations of t-PA and PAI-1 were quantified by enzyme-linked immunosorbent assay (ELISA). Chronic SDHs were divided into five groups according to their appearance on computed tomography: high-density (n = 4), isodensity (n = 8), low-density (n = 5), mixed-density (n = 3), layering (n = 3) types. The volume of hematoma was measured with an image analyzing software program. The concentrations of t-PA were higher in layering (41.2 +/- 0.3 ng/ml, mean +/- standard error of the mean) and high-density (40.0 +/- 1.1 ng/ml) types compared to those of low-density (23.3 +/- 4.1 ng/ml) and iso-density (25.1 +/- 3.7 ng/ml) types. The concentrations of PAI-1 were lower in layering (95.9 +/- 1.0 ng/ml) and high-density (103.4 +/- 34.5 ng/ml) types compared to that of low-density (192.5 +/- 2.6 ng/ml) type. So the ratio between t-PA and PAI-1 (t-PA/PAI) was greater in layering and high-density types. The volume of hematoma was larger in mixed-density and layering types but statistically insignificant. These results presumably suggest that the ratio between t-PA and PAI concentration may contribute to the pathogenesis of the chronic SDH.

Posttransplantation lymphoproliferative disorder in patients under primary tacrolimus (FK 506) immunosuppression

Posttransplantation lymphoproliferative disorder (PTLD) is a well-described complication of the systemic immunosuppression required for successful organ transplantation. Lesions of PTLD often occur in the region of the head and neck and require otolaryngologic evaluations. Although the majority of reported cases of PTLD are associated with cyclosporine immunosuppression, recently, PTLD has been described in patients treated solely with the newer systemic immunosuppressive agent tacrolimus (FK 506). As an introduction to tacrolimus and to PTLD as one of its complications, a case of PTLD presenting as airway obstruction in a child treated solely with tacrolimus immunosuppression is described. In addition, a review of tacrolimus and PTLD in patients under tacrolimus immunosuppression is presented to familiarize the otolaryngologist with this important new immunosuppressive agent and a potential complication of its use.

Pronounced activation of protein kinase C, ornithine decarboxylase and c-jun proto-oncogene by paraquat-generated active oxygen species in WI-38 human lung cells

Paraquat (methyl viologen, PQ) is a widely used herbicide that produces oxygen-derived free radicals and severely injures human lungs. In this study we examined the effects of PQ on the protein kinase C (PKC), ornithine decarboxylase (ODC) and c-jun oncogene expression in WI-38 human lung cells. Exposure of cells to 25-200 microM PQ resulted in an increase of [3H]phorbol dibutyrate (PDBu) binding and PKC redistribution in a dose-dependent manner. Interestingly, a superoxide dismutase mimic, 4-hydroxyl-2,2,6,6-tetramethyl-piperidine-1-oxyl (Tempol, 2.5 mM) and catalase (400 micrograms/ml) could significantly reduce the PQ-stimulated increase of phorbol ester binding and particular PKC phosphorylating activity, but dimethylsulfoxide (DMSO, 1.5%), an effective .OH trapping agent, failed to prevent this stimulation. In addition, an endogenous substrate of PKC, 80 kDa protein, was found to be highly phosphorylated in intact WI-38 cells treated with 50 microM PQ. The increase of phosphorylated proteins could be completely or partly abolished by Tempol or catalase, but only the phosphorylation of 80 kDa protein was diminished by protein kinase C inhibitor, 1-(5-isoquinolinyl-sulfonyl)-2-methylpiperazine (H-7). A maximal peak of ODC activity was observed at 6 h of treatment with 50 microM PQ. PQ induced activity was reduced at the following rates, Tempol 85%, DMSO 80% and catalase 45%, but H-7 failed to do so. Furthermore, we found that the level of c-jun mRNA was transiently increased by PQ and the peak appeared at 1 h of treatment. When correlated with the PKC result, Tempol, catalase and H-7 all effectively blocked PQ-elicited c-jun transcript expression, but DMSO only exhibited a weakly inhibitory effect. We therefore propose that superoxide anion (O2- and H2O2 generated by PQ could activate PKC and lead to induction of c-jun gene expression; on the other hand, O2- and .OH might trigger other kinase pathways to elevate ODC activity. Finally, the sequential expression of c-jun oncogene and ODC may cooperate to relieve the oxidative damages elicited by PQ.