Modelling the thermal inactivation of Salmonella typhimurium using bioluminescence data

Inactivation of micro-organisms by heat is a traditional food processing technique used to reduce or eliminate the microbial load in foods thus preventing bacterial associated disease and food spoilage. Models of thermal death kinetics are routinely used to predict the amount of heat required but such models are limited by the acquisition of accurate thermal death data for bacteria in situ and in complex microflora. In vivo bioluminescence from lux recombinant bacteria is an important alternative to traditional plate counts for examining bacterial injury and stress but the thermal instability of luciferase has appeared to preclude its application in heating studies. We have developed a procedure which overcomes the thermal instability of luciferase and demonstrate that computer generated models of the thermal injury of Salmonella typhimurium show equivalence between bioluminescence and viable count data.

Effects of EMS transportation on time to diagnosis and treatment of acute myocardial infarction in the emergency department

INTRODUCTION

Recent studies have documented decreased time to emergency department (ED) thrombolytic therapy with the use of prehospital electrocardiography.

PURPOSE

Is the time to ED diagnosis and treatment of acute myocardial infarction (AMI) patients with thrombolytic agents decreased by emergency medical services (EMS) transport when compared with those transported by other means (non-EMS)?

DESIGN

Retrospective, case-control study.

POPULATION

The AMI patients treated with thrombolytic agents at a 34,000-visit, community hospital ED during 1992.

METHODS

Review of records of patients who received thrombolytic therapy for AMI. Statistical analysis was performed using "Student's" t-test and Yates corrected Chi-square (chi 2).

RESULTS

Eighty-seven patients received thrombolytic agents for AMI during 1992; 33 arrived by ambulance, 54 arrived by other methods. There were no differences in age, gender, or time of ED arrival among these groups. Ambulance patients received standard advanced life support (ALS) care, but not a 12-lead electrocardiogram (ECG) or thrombolytic agents. Ambulance patients experienced a significantly shorter time to first ECG (12.9 +/- 9.1 min. versus 20.8 +/- 25.3 min.; p = .028) and received thrombolytic therapy sooner than did controls (56.0 +/- 31.5 min. versus 78.0 +/- 63.4 min.; p = .018). There was no difference in time from diagnosis to treatment between these groups.

CONCLUSION

Emergency medical services transport of AMI patients in this study decreased time to diagnosis and treatment and may be a confounder in studies that assess the value of field EMS interventions. Non-EMS AMI patients did not receive as rapid diagnosis and treatment, and emergency physicians should evaluate and address this issue in their departments.

The effect of dihydronicotinate N-substitution on the brain-targeting efficacy of a zidovudine chemical delivery system

Enhanced brain delivery of zidovudine (AZT) has been demonstrated using a redox-based chemical delivery system (CDS). Optimization of the prototype AZT-CDS (5'-[(1-methyl-1,4-dihydropyridin-3-yl)carbonyl]-3'-azido-3'-deoxy thymidine ) was investigated by manipulation of the N-methyl group present on the dihydronicotinate portion of the molecule and examining the release of AZT in vivo in a rat model. Of the five compounds examined, all produced higher brain levels and lower blood levels of AZT than did AZT itself. In comparing the novel AZT-CDS analogues to the N-methyl benchmark, the N-propyl system proved to be the most efficient of the compounds tested.

The impact of intraoperative autotransfusion on cardiac surgery. A prospective randomized double-blind study

The effect of intraoperative autotransfusion during coronary artery bypass grafting was studied in a randomized double-blind trial involving 38 patients. Nineteen patients had the collected RBCs washed and autotransfused (autotransfusion group), while the remaining patients had their washed cells discarded (control group). Postoperative hemoglobin and hematocrit values were similar. Exposure to banked blood was markedly decreased in the autotransfusion group compared with the control group. In addition, the mean volume of banked packed RBCs transfused per patient was significantly less in the autotransfusion group compared with the control group. Platelet utilization also was markedly decreased in the autotransfusion group. Cryoprecipitate and fresh frozen plasma utilization also was less in the autotransfusion group than in the control group, but this did not reach statistical significance. We conclude that the intraoperative use of autotransfusion decreases the volume of homologous blood products transfused, which results in reduced exposure of the patients to banked blood products.

Differential effects of diclofenac and aspirin on serum glutamic oxaloacetic transaminase elevations in patients with rheumatoid arthritis and osteoarthritis

OBJECTIVE

To examine elevations in levels of serum glutamic oxaloacetic transaminase (SGOT) in patients with rheumatoid arthritis (RA) and osteoarthritis (OA) taking placebo, aspirin, or diclofenac, and to seek possible explanations for the occurrence of these elevations.

METHODS

We conducted a meta-analysis of individual case reports from 3 RA protocols and 5 OA protocols, encompassing 814 diclofenac-treated patients, 443 aspirin-treated patients, and 359 placebo-treated patients. All of the RA protocols had nearly identical inclusion and exclusion criteria, as well as safety studies and followup; the same was true for the OA protocols. Analysis included correlation analysis and multiple linear and logistic regression, accounting for numerous potential confounding variables, with the SGOT as the dependent variable. F tests were used for hypothesis testing.

RESULTS

By several analytic approaches, the principal determinants of SGOT concentrations were found to be baseline SGOT value, the use of aspirin in RA patients, and the use of diclofenac in OA patients. Other significant factors contributing to an increase in SGOT concentrations were duration of therapy and, perhaps, daily dosage (mg/lb). Hypothesis testing supported these results. Given a statistically average patient, we predicted a 1-2% chance of a mildly elevated SGOT level occurring among placebo-treated patients, a 6-7% chance among diclofenac- or aspirin-treated patients with RA, a 12% chance among diclofenac-treated patients with OA, and a 2% chance among aspirin-treated patients with OA.

CONCLUSION

This study demonstrates a powerful method for performing meta-analysis, using available individual patient data to examine numerous factors that may affect an outcome of interest. In this case, mild elevations of SGOT were examined and found to be related to baseline SGOT levels, diclofenac use (in OA), and aspirin use (in RA). Of numerous other potential factors examined, including age, sex, alcohol use, concomitant medications, and concomitant diagnoses, only duration of therapy and, to a small extent, daily dosage, were also consistent determinants of SGOT elevation. The SGOT elevations were minimal and were not related to the occurrence of clinical hepatitis: No clinical hepatitis occurred.

Patient use and assessment of conventional and alternative therapies for HIV infection and AIDS

OBJECTIVE

To investigate the extent of recourse to alternative therapies among 184 HIV-positive patients who continued to attend conventional medical clinics. The study describes the specific alternative therapeutic modalities that were more commonly sought by our respondents, and provides data on the subjective assessment of the efficacy of both conventional and alternative therapies.

METHODS

Demographic and behavioral information were obtained from standard, self-administered, anonymous questionnaires distributed at three HIV clinics in the Philadelphia area.

RESULTS

Forty per cent of patients reported having used alternative or complementary therapies. Forty-two per cent of respondents who had been enrolled in clinical trials had used alternative therapies at some stage. Recourse to such therapies was significantly associated with risk-group affiliation, duration of seropositivity, and sex. The decision to use alternative therapies was not significantly related to age, race, education, religion or severity of symptoms. Of respondents using alternatives, 10% expected the unconventional treatments to cure their HIV infection, and 36% expected them to delay the onset of symptoms.

CONCLUSION

The results of this study will contribute to conventional practitioners' understanding of those unconventional explanations and therapies for HIV infection that many patients find relevant and meaningful. Health-care workers should be aware of their patients' interest in participating in decisions about their treatment--whether alternative or conventional--and be prepared to work with them to achieve satisfactory outcomes.

The peripheral modulation of duodenal and colonic motility in rats by the pancreatic polypeptide-fold family: neuropeptide Y, peptide YY, and pancreatic polypeptide

Neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP) altered intraluminal pressure in the duodenum and colon of fasted anesthetized rats following intravenous bolus administration. There were rapid increases in intraluminal pressure of the duodenum and colon of anesthetized rats following peripheral injections of NPY, PYY and PP. Administration (IV) of NPY, PYY, and PP increased intraduodenal pressure +1.8, +3.2, and +3.7 mmHg compared to saline baseline. Prazosin, an alpha-2 adrenergic antagonist, did not alter the response of the duodenum of urethane-anesthesized rats to any of the PP-fold peptides following peripheral administration. Yohimbine, an alpha 2-adrenergic antagonist, attenuated the excitatory response of rat duodenum following NPY (IV) but did not alter the duodenal response to PP (IV). Intravenous NPY, PYY, and PP increased intracolonic pressure +2.0, +3.3, and +6.2 mmHg compared to saline baseline. In the presence of prazosin, an alpha 1-adrenergic antagonist, the intraluminal pressure of the colon increased +2.6, +2.4, and +8.1 mmHg compared to saline baseline by NPY, PYY, and PP (IV), respectively. In the presence of alpha 2-adrenergic blockade by yohimbine, NPY, PYY, and PP (IV) increased intraluminal pressure of the colon +4.2, +2.9, and +2.5 mmHg compared to saline baseline. The response of the duodenum to the excitatory effect of PYY (IV) was enhanced in the presence of yohimbine. Duodenal and colonic tone were modulated by the PP-fold peptides following peripheral administration. The alpha-adrenergic nervous system played only a minor role in the modulation of GI motility by the PP-fold peptides at peripheral sites.

Improved detection of antibodies to hepatitis C virus in dialysis patients using a second-generation enzyme immunoassay

We tested serum samples from 99 patients undergoing maintenance hemodialysis for hepatitis C virus (HCV) antibodies using a first-generation, licensed anti-HCV enzyme immunoassay (EIA) and a second-generation anti-HCV EIA that detect three gene products c100-3, NS3, and core. Specimens that were repeatedly reactive by either or both screening assays were further evaluated by testing with supplemental EIAs and a dot blot immunoassay. There was 87.9% agreement between the licensed HCV EIA and the HCV EIA second generation. HCV EIA Second Generation detected 10 more positive specimens than HCV EIA, for an increase in detection from 33.3% (33/99) to 43.4% (43/99). We conclude that HCV EIA Second Generation improves detection of HCV infection in hemodialysis patients.

The reasoning of the strongest: the polemics of skill and science in medical diagnosis

This paper describes the efforts of clinical scientists and computer experts to introduce computer diagnosis into the wards of a major Australian teaching hospital during the 1960s and 1970s. A logical-empiricist procedure construed as a `scientific' model of medical diagnosis — and thus challenging traditional physicians' claims of `craft knowledge' — had the potential to define a new social and institutional role for clinical research. In this account, the `craft' and `scientific' representations of diagnosis are treated symmetrically, as discursive resources used in a hospital context to legitimate the divergent competences of two competing occupational subgroups. Neither `skill' nor `science' is privileged as an explanatory framework. Attributions of skill — as of rationality — may serve distinct social goals and institutional interests. In order to secure a place for this diagnostic technology clinical scientists appealed to a scientific method that physicians were prepared to use rhetorically to bolster their diagnoses — but not, in the end, to redefine the diagnostic process. The institutional authority of physicians in this case allowed them to ignore a model of diagnosis that would circumvent their control of a crucial aspect of medical work.

Diagnostic value of pleural fluid cytology in occult Boerhaave's syndrome

When Boerhaave's syndrome presents with atypical clinical features and eludes prompt diagnosis, delays in surgical therapy increase complications and mortality. We present a patient with occult Boerhaave's syndrome who had nondiagnostic esophageal contrast studies and thoracic computed tomography. Pleural fluid cytologic analysis established the presence of esophageal rupture by detecting undigested food particles.

Neuropeptide Y, peptide YY, and pancreatic polypeptide modulate duodenal and colonic motility at a thoracic spinal site in rats

Neuropeptide Y, PYY, and PP (200 pmol) alter intraluminal pressure in the duodenum and colon of rats following their administration into the thoracic (T8-T10) region of the spinal cord. Neuropeptide Y decreases the tone of the duodenum and the colon following intrathecal (T8-T10) administration prior to an increase in tone to baseline or greater. There is no effect on intraluminal pressure of either the duodenum or the colon following intrathecal administration of NPY or PP into the lumbar (L4-L5) region of the spinal cord. Following intrathecal (T8-T10) administration of PYY and PP, increases in intraduodenal pressures are observed (+2.1 and +3.0 mmHg from saline baseline). Phasic contractions of the duodenum are increased following intrathecal administration of PYY into the thoracic spinal cord of rats. Neuropeptide Y, PYY, and PP increase intracolonic pressure +2.2, +3.3, and +3.7 mmHg from saline baseline, respectively. Phasic contractions of the colon are increased following PP intrathecal thoracic administration. Responsiveness of the duodenum or colon to the different ligands of the PP-fold peptide family in the absence of alpha-adrenergic blockade did not vary. The increases in intraluminal pressure of the duodenum and colon following intrathecal administration of the PP-fold peptides are attenuated by both alpha-1 adrenergic (prazosin) and alpha-2 adrenergic (yohimbine) blockade. There is a difference in responsiveness of the colon between the ligands of the PP-fold family in the presence of the alpha-2 adrenergic blockade. The findings of this study indicate that duodenal and colonic motility are modulated by the PP-fold peptides at thoracic spinal sites via alteration of sympathetic outflow.

Evaluation of a respiratory rate monitor in postsurgical patients

STUDY OBJECTIVE

To evaluate the clinical use of a cardiorespiratory rate monitor in patients receiving epidural opioids following major surgery.

DESIGN

For 6 hours during the night following surgery, patients were continuously monitored with a cardiorespiratory rate monitor and a pulse oximeter, as well as by an in-room observer.

SETTING

Postoperative surgical ward at a university hospital.

PATIENTS

Eight ASA physical status I and II patients ages 30 to 76 years.

INTERVENTIONS

Any bradypneic, hypoxemic, bradycardic, or tachycardic event was confirmed by the observer and recorded.

MEASUREMENTS AND MAIN RESULTS

The cardiorespiratory rate monitor accurately identified true bradypneic episodes in five of the eight patients. There were no false-positive alarms. The respiratory rate monitor and the pulse oximeter identified one episode of hypoxemia. There were no episodes of bradycardia or tachycardia.

CONCLUSIONS

The cardiorespiratory rate monitor is useful in patients at risk for bradypnea following surgery.

The New York Needle Trial: the politics of public health in the age of AIDS

During the past 5 years, the exchange of sterile needles and syringes for dirty injecting equipment has gained increasing acceptance outside the United States as a potential means of reducing the transmission of the human immunodeficiency virus (HIV) among intravenous drug users. This article describes the controversy over attempts to establish a needle and syringe exchange scheme in New York City between 1985 and 1991. The response to a health crisis is used as an indicator of patterns of social and institutional practice. Advocates of needle exchanges had reached a stalemate with the promoters of law enforcement, and the strategic reformulation of the policy problem in terms of the research process seemed to offer a solution. The article discusses the practical limitations on designing and carrying out a controversial health promotion policy; the use (under constraint) of a restrictive research process to constitute--rather than simply to guide or monitor--public policy; and the potential ethical hazards of health professionals' seeking a polemical recourse to the clinical trial. The efforts to establish a needle exchange in New York thus illustrate more general problems for AIDS prevention.

Chronic renal failure secondary to post-hysterectomy vaginal prolapse

The first case of posthysterectomy vaginal prolapse and associated chronic renal failure requiring hemodialysis is presented. A review of the literature on vaginal prolapse and the mechanism and physiology of chronic renal obstruction in this setting is reviewed.

Acute theophylline intoxication

We describe a case of intentional acute theophylline intoxication with cardiac, cerebral, and gastrointestinal features of moderate-to-severe toxicity. The unusual metabolic and hematologic sequelae included hypokalemia, hyperglycemia, metabolic acidosis, extreme neutrophilia, increased creatinine levels attributed to muscle damage, and hematuria. The implications of these unusual findings for the management of acute theophylline intoxication include the recognition that these effects can be due to intoxication per se and do not necessarily indicate a primary endocrine disorder or infection.

Brain, blood, and cerebrospinal fluid distribution of a zidovudine chemical delivery system in rabbits

Improved brain delivery of zidovudine (AZT) was shown to occur after iv dosing of a chemical delivery system (CDS) for the modified deoxynucleoside. Specifically, administration of a 25-mg/kg dose of 5'-[(1-methyl-1,4-dihydropyridin-3-yl)carbonyl]-3'-azido-3'-deoxyt hymidine (AZT-CDS) generated higher and more sustained levels of AZT in brain tissue of rabbits than did dosing with AZT itself. The significant increase in the area under the AZT brain concentration-time curve occurred with lower AZT present in the systemic circulation and with similar AZT levels in cerebrospinal fluid. These results, as well as previously published reports examining AZT-CDS in mice, rats, and dogs, indicate that this delivery system may be beneficial in the treatment of AIDS-related encephalopathy.

Pulmonary nodule: evaluation with spiral volumetric CT

Spiral volumetric computed tomography (CT) was used prospectively in 20 patients with a suspected solitary pulmonary nodule less than 1 cm in diameter on plain chest radiographs. Four additional nodules were detected with spiral CT than were detected with conventional CT. This technique required a 12-second breath hold; patient cooperation was excellent.

Threshold dose for peripheral neuropathy following intraoperative radiotherapy (IORT) in a large animal model

Radiation injury to peripheral nerve is a dose-limiting toxicity in the clinical application of intraoperative radiotherapy, particularly for pelvic and retroperitoneal tumors. Intraoperative radiotherapy-related peripheral neuropathy in humans receiving doses of 20-25 Gy is manifested as a mixed motor-sensory deficit beginning 6-9 months following treatment. In a previous experimental study of intraoperative radiotherapy-related neuropathy of the lumbro-sacral plexus, an approximate inverse linear relationship was reported between the intraoperative dose (20-75 Gy range) and the time to onset of hind limb paresis (1-12 mos following intraoperative radiotherapy). The principal histological lesion in irradiated nerve was loss of large nerve fibers and perineural fibrosis without significant vascular injury. Similar histological changes in irradiated nerves were found in humans. To assess peripheral nerve injury to lower doses of intraoperative radiotherapy in this same large animal model, groups of four adult American Foxhounds (wt 20-25 kg) received doses of 10, 15, or 20 Gy to the right lumbro-sacral plexus and sciatic nerve using 9 MeV electrons. The left lumbro-sacral plexus and sciatic nerve were excluded from the intraoperative field to allow each animal to serve as its own control. Following treatment, a complete neurological exam, electromyogram, and nerve conduction studies were performed monthly for 1 year. Monthly neurological exams were performed in years 2 and 3 whereas electromyogram and nerve conduction studies were performed every 3 months during this follow-up period. With follow-up of greater than or equal to 42 months, no dog receiving 10 or 15 Gy IORT shows any clinical or laboratory evidence of peripheral nerve injury. However, all four dogs receiving 20 Gy developed right hind limb paresis at 8, 9, 9, and 12 mos following intraoperative radiotherapy. These experimental data suggest that intraoperative doses of less than 20 Gy may not result in clinically significant peripheral nerve injury with follow-up of 3.5 years. Longer (5 yrs) follow-up with planned sacrifice of the remaining dogs is scheduled to assess any late peripheral nerve damage.

Redox derivatives of tranylcypromine: syntheses, properties, and monoamine oxidase inhibitor activity of some chemical delivery systems

Several brain-targeting chemical delivery systems (CDS) based on a dihydropyridine----pyridinium salt type redox system were synthesized for the monoamine oxidase (MAO) inhibitor tranylcypromine (TCP). The dihydronicotinate moiety was chemically attached to the amino group of TCP by either an amide or substituted carbamate linkages. Physicochemical studies of the new derivatives, including chromatographic Rm determinations, were performed. Only the substituted carbamate-type derivatives manifested an increased lipophilicity relative to the parent compound. In vitro oxidation stability studies were also performed on selected derivatives using a ferricyanide-mediated method. Results of this assay showed that the dihydropyridine-type derivatives oxidized to the respective quaternary salt forms with stabilities which empirically correlated with other effective CDSs. Preliminary in vivo studies performed in rats indicated that some of the new derivatives exerted significant biological activity.

Cochlear implantation of totally deaf ears. Histologic evaluation of candidacy

Successful cochlear implantation depends on the presence of stimulatable neural elements, which are believed to be the spiral ganglion, neurons, or their axons. We examined the 1,152 temporal bones in our laboratory to determine how many with a total sensorineural hearing loss would be implantable. We defined implantable as having 3,500 neurons or more, as determined by successful implant stimulation in two ears from our collection with less than 3,500 neurons. Of 46 bones with deafness, 37 had 3,500 neurons or more and would be considered implant candidates. The types of deafness in the potentially implantable ears and in ears with sufficient neural elements will be discussed.

Tumor induction following intraoperative radiotherapy: late results of the National Cancer Institute canine trials

Intraoperative radiotherapy has been employed in human cancer research for over a decade. Since 1979, trials to assess the acute and late toxicity of IORT have been carried out at the National Cancer Institute in an adult dog model in an attempt to establish dose tolerance guidelines for a variety of organs. Of the 170 animals entered on 12 studies with a minimum follow-up of 2 years, 148 dogs received IORT; 22 control animals received only surgery. Animals were sacrificed at designated intervals following IORT, usually at 1, 6, 12, 24, and 60 month intervals. 102 of 148 irradiated dogs were sacrificed less than 24 months; 46 dogs were followed greater than or equal to 24 months after IORT. To date, 34 of the 46 animals have been sacrificed; the 12 remaining animals are to be followed to 5 years. These 12 animals have minimum follow-up of 30 months. In the irradiated group followed for greater than or equal to 24 months, 10 tumors have arisen in 9 animals. One animal developed an incidental spontaneous breast carcinoma outside the IORT port, discovered only at scheduled post-mortem exam. The remaining nine tumors arose within IORT ports. Two tumors were benign neural tumors--a neuroma and a neurofibroma. One animal had a "collision" tumor comprised of grade I chondrosarcoma adjacent to grade III osteosarcoma arising in lumbar vertebrae. Two other grade III osteosarcomas, one grade III fibrosarcoma, and one grade III malignant fibrous histiocytoma arose in retroperitoneal/paravertebral sites. An embryonal rhabdomyosarcoma (sarcoma botryoides) arose within the irradiated urinary bladder of one animal. No sham irradiated controls nor IORT animals sacrificed less than 24 months have developed any spontaneous or radiation-induced tumors. The time range of diagnoses of tumors was 24-58 months (median 40 months). The IORT dose range associated with tumor development was 20-35 Gy (median 30 Gy). The carcinogenesis capability of single fraction, high dose radiation in animals is discussed, as are the implications of these data for continued research and clinical usage of IORT in the treatment of humans.

Hypothermia increases calcium content of hypoxic myocytes

To test the hypothesis that hypothermia prevents myocardial Ca2+ loading during reoxygenation, we examined the effects of 2 h of hypoxia with and without hypothermia on the Ca2+ content of cultured chick embryo ventricular cells. When compared with hypoxic cells at 37 degrees C, hypoxia at 11 degrees C (hypothermia) augmented the 45Ca content of cardiocytes after 30 min of normothermic reoxygenation from 3.85 +/- 0.2 to 4.7 +/- 0.1 nmol/mg protein (P less than 0.001). The Na+ content of hypoxic myocytes was also increased at the end of 2 h of hypoxia from 648 +/- 59 to 1,026 +/- 68 nmol/mg protein in cells exposed to hypoxia at 11 degrees C (P less than 0.001). Hypothermia ameliorated hypoxia-induced depression of cellular ATP content and did not result in significant membrane injury as determined by lactate dehydrogenase release. These data indicate that hypothermia augments rather than decreases the Ca2+ content of hypoxic myocytes during reoxygenation after hypoxia. Ca2+ loading appears to be secondary to an increase in Na+ content, creating a favorable gradient for Ca2+ influx through Na(+)-Ca2+ exchange or an unfavorable gradient for Ca2+ extrusion.

Antihypertensive activity of redox derivatives of tryptophan

The essential amino acid, tryptophan, has been shown to lower blood pressure in rats when administered orally or intravenously. In order to potentially enhance this action, a brain-targeting chemical delivery system (CDS) approach was applied to this compound. The CDS is based on a dihydropyridine----pyridinium ion redox system, chemically analogous to the naturally occurring NADH----NAD+ system. The dihydropyridine moiety containing carrier is chemically attached to the amino group by an amide-type bonding while the carboxylic acid functionality is esterified to various alcohols. Physicochemical studies of the new derivatives were performed. The determined chromatographic Rm values indicate an increased lipophilicity for the CDSs compared to the parent compound. Oxidation stability studies performed on selected compounds using a ferricyanide-mediated method showed that the CDSs are oxidized to the respective quaternary salt forms. Activity studies performed in deoxycorticosterone acetate induced hypertensive rats, demonstrated that the delivery system for tryptophan reduced blood pressure more efficiently for a longer time than did the parent compound.

[3H]prostaglandin uptake in vivo by rabbit uterine tissues and blastocysts

Day-6 pregnant rabbits were anesthetized and subjected to a mid-ventral laparotomy. [3H] Prostaglandin F2alpha) (PGF2alpha) [3H]PGE2, [14C]Urea or [14C]Sucrose were instilled into the uterine lumen via the uterotubal junction. The amounts instilled/uterine horn were respectively 3.7 +/- 0.3, 3.5 +/- 0.3, 5.7 +/- 1.3 and 2.7 +/- 1.6 muCi in 20mul of buffer. Animals were killed at 1, 2, 9, 19 or 21 h after radioactive instillation, and the amounts of radioactivity in blastocysts, uterine tissue, peritoneal cavity washings and urine evaluated by liquid scintillation spectrometry. A gradient of radioactivity was observed from the uterotubal junction to the cervical end of the uterus. Large amounts of [3H]PG were found in the injected horn and associated blastocysts with a considerable crossover to the non-injected horn, but little in the associated blastocysts. Much of the blastocysts associated- [3H]PG remained unmetabolized. Large amounts of metabolized [3 H] were found in urine. [14C]Urea was taken up by uterine tissue in the injected horn, but there was little cross over to the non-injected horn. Urea was also found in urine. Much of the [14C]Sucrose remained in the injected horn, and little was recovered from the urine. It was found that at 9 h, but not at 19 h, after [3 H]PG instillation, the PG was localized at the site of the blastocysts in the injected but not in the contralateral horn. Significantly more [3H]PGF2alpha than [3H]PGE2 was localized in this situation. [14C]Urea was not localized at the site of the blastocysts in urea injected horns. (ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics and distribution of recombinant secretory leukocyte proteinase inhibitor in rats

Secretory leukocyte proteinase inhibitor (SLPI) is a potent elastase, trypsin, and chymotrypsin inhibitor occurring in all mucous secretions. Its inhibitory potency and profile suggested that it may become a therapeutic adjuvant in diseases where proteinases play a pathogenetic role. In the course of developing recombinant SLPI for therapeutic purposes, we studied its pharmacokinetics after intravenous, intraperitoneal, and intratracheal application to rats. In plasma, SLPI was determined with an ELISA or by following a radiotracer [( 35S]SLPI). In bronchoalveolar lavage fluid (BALF), SLPI was determined additionally by a functional assay (elastase inhibitory capacity). Intravenously applied SLPI (2 mg/kg) was rapidly cleared, with half-times of distribution of 6 min and half-times of elimination of 50 min. Very little (less than 5%) appeared in the urine even after 24 h. Approximately 80% of intraperitoneally injected SLPI (12 mg/kg) was absorbed and generated maximal plasma concentration of 6 to 10 micrograms/ml 30 to 120 min after administration. When given intratracheally (8.6 mg/kg), SLPI disappeared from the lungs, with a half-time of 4 to 5 h. This value was the same whether the remaining SLPI in BALF was determined radiometrically, by ELISA or by the functional assay, indicating minimal metabolism in the lung. As in the case of intraperitoneal application, SLPI was absorbed systemically, resulting in a maximal plasma level of about 2 micrograms/ml 1 to 2 h after application. In contrast to the measurements in BALF, the ELISA and radiotracer measurements in plasma correlated only for the first 2 h after application and diverged progressively after that, suggesting breakdown of the molecule once it reaches the plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

125I-iodopindolol binding to frog esophageal peptic cells. Detection of amine uptake and beta-adrenergic receptors coupled to pepsinogen secretion

The beta-adrenergic receptors (beta-ARs) coupled to pepsinogen secretion on frog esophageal peptic cells have been compared to frog erythrocyte beta-ARs using the radioligand 125I-iodopindolol (125I-PIN). 125I-PIN binding to intact peptic cells was time and temperature dependent. Saturation and competition experiments established that a large component of this binding represented radioligand uptake, which was energy dependent, pH sensitive, Na+ independent, and inhibited by agents that depress cellular ATP or disrupt proton gradients. This uptake system, which was absent from frog erythrocytes, appeared similar to that recently described for a number of mammalian cells. 125I-PIN bound to a single class of sites on peptic cell homogenates with a KD = 64 (+/- 5) pM. Binding to cell homogenates and a proportion of the binding to intact cells was inhibited by beta-agonists and antagonists with pharmacological characteristics similar to typical beta 2-ARs of frog erythrocytes. The number of beta-ARs in these peptic cell preparations was 1300 (+/- 240) sites/cell. Isolated peptic cells were poorly responsive to isoproterenol stimulation even in the presence of the phosphodiesterase inhibitor IBMX (3-isobutyl-1-methylxanthine). Pretreatment of cells with the phorbol ester TPA (12-O-tetra-decanoylphorbol-13-acetate) (100 nM) promoted isoproterenol stimulation of pepsinogen secretion. Catecholamine agonists stimulated pepsinogen secretion with an order of potency: isoproterenol greater than epinephrine much greater than norepinephrine, which was identical to that determined for inhibition of 125I-PIN binding. These findings indicate that frog peptic cells contain beta 2-ARs functionally coupled to pepsinogen secretion.

Counselors' reports of their use of self-disclosure with clients

Ninety-six counselors indicated the frequency of their use of 11 types of self-disclosure, which varied in intimacy from incidental information (age, race) to personal weaknesses. Positive emotional responses to clients were used most frequently, and opinions/attitudes were used least frequently. A factor analysis showed three factors to describe the data best. Factor 1 was represented by information related to the personal identify and experiences of the therapist. Factor 2 involved the emotional responses of the therapist to the client. Factor 3 was principally the disclosure of professional experiences and identity. Implications are considered.

A comparison of radiation doses to the breast in computed tomographic chest examinations for two scanning protocols

Compared with other radiological examinations in which the breasts are directly exposed, the breast doses involved in computed tomographic (CT) chest examinations are high. A CT protocol which reduces such breast dose has been investigated. Breast doses have been measured for contiguous 10 mm scans and interspaced 3 mm scans. Differences in the breast doses were found between the left and right breasts for both scanning protocols. The dose associated with the interspaced scans was lower by a factor of about two compared with that for the contiguous scans.

Partial agonist activity of the bombesin-receptor antagonist [Leu14-psi-CH2-NH-Leu13]-bombesin in frog peptic cells

The pseudopeptide [Leu14-psi-CH2NH-Leu13]-bombesin inhibited 125I-GRP binding to membrane preparations of frog cerebrum and peptic cells, rat cerebral cortex and pancreas with IC50's of 44-250 nM (using 180 pM 125I-GRP). It was unable to stimulate amylase release from rat pancreatic acini, but antagonized competitively BB stimulated amylase release with an IC50 of 130 nM. By contrast the pseudopeptide stimulated pepsinogen secretion from frog esophageal peptic cells with an efficacy relative to bombesin of 36%, and with an EC50 of 30 nM. By virtue of its partial agonist activity it inhibited submaximal BB stimulated responses to a level equal to the pseudopeptide alone. Thus [Leu14-psi-CH2NH-Leu13]-BB differentiates certain BB receptors by exhibiting selective intrinsic efficacy.

Myocardial protection in cyanotic neonatal lambs

To investigate the susceptibility of cyanotic neonatal myocardium to ischemia and the effectiveness of cardioplegia for protection, we induced cyanosis in 2- to 5-day-old lambs (n = 16) by connecting the left atrial appendage to the main pulmonary artery with a 4 mm polytetrafluoroethylene graft, which produced an arterial oxygen tension of 34.1 +/- 1.2 torr. Seven to 10 days after creation of the model, isolated perfused hearts from cyanotic animals were subjected to 2 hours of ischemia with topical cooling or crystalloid cardioplegia (K = 30 mEq/L) for myocardial protection (both at 15 degrees C). Identical studies were performed on hearts from 16 normoxemic neonatal lambs 5 to 14 days old. The overall effect of cyanosis was to produce a significant impairment in recovery of maximum developed pressure (p less than 0.05) after ischemia. The overall effect of cardioplegia was to produce a significant improvement in recovery of maximum developed pressure, developed pressure at V10 (the balloon volume to produce an end-diastolic pressure of 10 mm Hg during the preischemic period), and peak rate of pressure rise at V10 (p less than 0.05). The protective effect of cardioplegia was more prominent in cyanotic hearts than in normoxemic hearts for recovery of maximum of peak rate of pressure rise and peak rate of pressure rise at V10 (p less than 0.05). End-diastolic pressure at V10 and the diastolic stiffness constant at 10 and 20 mm Hg were all significantly higher after ischemia in the cyanotic hearts than in the normoxemic hearts (p less than 0.05). We conclude that in neonatal hearts cyanosis may increase the vulnerability to ischemia and cardioplegia appears to enhance the recovery of systolic but not diastolic function in these hearts.

Muscarinic cholinergic receptor subtype on frog esophageal peptic cells: binding and secretion studies

The muscarinic receptors coupled to pepsinogen secretion on isolated frog esophageal peptic cells have been characterized using functional and radioligand binding techniques. N-[3H]methylscopolamine [( 3H]NMS) binding to intact cells was complex and indicative of a high affinity, low capacity site and a high capacity uptake site. Binding to the high capacity site was inhibited by atropine with high affinity (IC50, 3 nM) and by imipramine and propranolol with IC50 values of 70 and 270 nM, respectively. After inhibition of uptake by 30 microM propranolol, [3H]NMS bound to a single population of high affinity sites (KD, 125 +/- 16 pM), which exhibited binding site maximum of 2.1 fmol/10(6) cells, equivalent to 1260 sites/cell. Binding to these sites was reversible, stereoselective and inhibited by muscarinic receptor agonists with an order of potency: oxotremorine greater than acetylcholine greater than carbachol greater than bethanechol and by antagonists with an order of potency:atropine greater than 4-diphenylacetoxy-N-methylpiperidine methobromide greater than pirenzepine greater than AF-DX 116 (11-2[2-[[diethylamino) methyl]-1-piperidinyl]acetyl]-5, 11-dihydro-6H-pyrido[2,3-b][1,4]-benzodiazepine-6-one). Pepsinogen secretion was stimulated by the agonists with an order of potency: acetylcholine greater than or equal to carbachol greater than oxotremorine greater than bethanechol. Atropine, pirenzepine and AF-DX 116 competitively inhibited carbachol-stimulated pepsinogen secretion with pA2 values of 9.58, 7.37 and 6.68, respectively, which correlated with their log (inhibition constants) for receptor binding. By contrast, agonists with significant efficacy exhibited EC50 values which were 20 to 90 times lower than their inhibition constants for binding which suggests the possibility of "spare" muscarinic receptors. Our findings indicate that functional muscarinic receptors on peptic cells exhibit similar characteristics to the high affinity sites labeled by [3H]NMS.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibody responses to malarial antigens in the Wopkaimin population of the Star Mountains, Papua New Guinea

Antibody responses to malarial antigens were determined in 614 serum samples collected from the Wopkaimin population of the Star Mountains of Papua New Guinea. In point prevalence surveys made in 1982-1983, 33.7% of the persons examined were infected with Plasmodium falciparum, P. vivax, or P. malariae. Of these, 72.9% were infected with P. falciparum. In a standard fluorescent antibody test, highest level responses were to P. falciparum, followed by P. malariae, P. vivax, and P. ovale. A strong correlation was found between results of the fluorescent antibody tests and those obtained in an enzyme-linked immunosorbent assay using P. falciparum antigens. The failure of immune responses to eliminate these species of Plasmodium in this highly isolated population is discussed.

Information systems planning at the University Medical Center of Southern Nevada

In summary, UMC benefitted from the planning process and resulting information systems plan because the Medical Center was better able perform the following tasks: Understand organizational interrelationships; Identify organizational and user needs; Set enterprise-wide priorities; Document information systems needs, priorities, and relationships; Ensure management and user agreement on system direction and sequence prior to system implementation; Maximize opportunities for cost effectiveness and operational efficiency; and Define functional requirements of systems. Essential to the above tasks and resulting benefits were an executive management team at UMC which worked together to plan, and departmental managers who assessed their individual needs in the light of UMC's overall strategy.

Basophilic leukemia and the hypersecretion of gastric acid and pepsin

A 48-yr-old man with chronic myelogenous leukemia and basophilia developed a duodenal ulcer and hemorrhage. Gastric analysis revealed basal hyper-secretion of acid (33.1 mEq/h) and pepsin (44.5 x 10(-4) peptic units/h). Blood, serum, and urine histamine was elevated and serum gastrin was normal. Although acid output was markedly suppressed with ranitidine (50 mg i.v.), pepsin secretion was only inhibited 63% and had returned to basal levels by the sixth hour. Maximal acid output does not suggest a trophic effect of histamine in this patient. The previously reported cases of basophilic leukemia and gastric hypersecretion or duodenal ulcer disease are reviewed.

Effect of tranexamic acid on gastric bleeding in rats

Bleeding from an induced gastric mucosal wound was monitored for 2 h in a rat model, in which normal hemostasis was disturbed mechanically by perfusing the lesion with saline. The hemorrhage was characterized by continuous bleeding and/or episodes of spontaneous rebleeding, as often seen in patients with gastric hemorrhage. The antifibrinolytic agent, tranexamic acid, significantly reduced total bleeding volume and number of rebleeding episodes, suggesting that plasmin-induced fibrinolysis might aggravate gastric mucosal hemorrhage.

Clinical evaluation of the Pollenex BP-850 automatic sphygmomanometer

Eighty subjects were assigned to two conditions in which readings of blood pressure were taken simultaneously by an observer using a Hawkesley Random Zero Sphygmomanometer and by a Pollenex BP-850 Automatic Sphygmomanometer either in its standard form or silenced to stop it bleeping whilst recording blood pressure. Forty subjects were assigned to a comparison group, where simultaneous readings by two observers were taken from one Hawkesley. Analyses performed included correlations, t-tests, and Bland and Altman's (Lancet, 1986, i: 307-310) differences against the mean method. Cues from observer behaviours or the bleeping Pollenex resulted in higher concordance between measures in the standard condition and the Hawkesley comparison condition. However, even in the silent condition the Pollenex proved to be as reliable a monitor of blood pressure as the Hawkesley.