Correction: Upregulation of annexin A1 protein expression in the intratumoral vasculature of human non-small-cell lung carcinoma and rodent tumor models

[This corrects the article DOI: 10.1371/journal.pone.0234268.].

Metabolite-Based Modification of Poly(l-lysine) for Improved Gene Delivery

Synthetic gene delivery systems employ multiple functions to enable safe and effective transport of DNA to target cells. Here, we describe metabolite-based poly(l-lysine) (PLL) modifiers that improve transfection by imparting both pH buffering and nanoparticle stabilization functions within a single molecular unit. PLL modifiers were based on morpholine (M), morpholine and niacin (MN), or thiomorpholine (TM). PLL modification with (MN) or (TM) imparted buffering function over the pH range of 5-7 both in solution and live cells and enhanced the stability of PLL DNA nanoparticles, which exhibited higher resistance to polyanion exchange and prolonged blood circulation. These properties translated into increased transfection efficiency in vitro coupled with reduced toxicity compared to unmodified PLL and PLL(M). Furthermore, PEG-PLL(MN) DNA nanoparticles transfected muscle tissue in vivo for >45 days following intramuscular injection. These polymer modifiers demonstrate the successful design of multifunctional units that improve transfection of synthetic gene delivery systems while maintaining biocompatibility.

Engineering Caveolae-Targeted Lipid Nanoparticles To Deliver mRNA to the Lungs

Efficacious use of therapeutic gene delivery via nanoparticles is hampered by the challenges associated with targeted delivery to tissues of interest. Systemic administration of lipid nanoparticle (LNP)-encapsulated mRNA leads to a protein expressed predominantly in the liver and spleen. Here, LNP encapsulating mRNA was covalently conjugated to an antibody, specifically binding plasmalemma vesicle-associated protein (PV1) as a means to target lung tissue. Systemic administration of PV1-targeted LNPs demonstrated significantly increased delivery of mRNA to the lungs and a 40-fold improvement in protein expression in the lungs, compared with control LNPs. We also investigated the effect of LNP size to determine optimal tissue distribution and transfection. Larger-size PV1-targeted LNPs not only have the elasticity to target the PV1 expressed in the caveolae but also enable robust mRNA expression in the lungs. Targeted delivery of mRNA to the lungs is a promising approach in the treatment of lung diseases.

Antibody Fragment F(ab')2 Targeting Caveolae-Associated Protein PV1 for Selective Kidney Targeting and Retention

Targeted strategies to deliver and retain drugs to kidneys are needed to improve drug accumulation and efficacy in a myriad of kidney diseases. These drug delivery systems show potential for improving the therapeutic windows of drugs acting in the kidney. Biodistribution of antibody-based therapeutics in vivo is governed by several factors including binding affinity, size, and valency. Investigations of how the biophysical and biochemical properties of biologics enable them to overcome biological barriers and reach kidneys are therefore of interest. Although renal accumulation of antibody fragments in cancer diagnostics and treatment has been observed, reports on effective delivery of antibody fragments to the kidneys remain scarce. Previously, we demonstrated that targeting plasmalemma vesicle-associated protein (PV1), a caveolae-associated protein, can promote accumulation of antibodies in both the lungs and the kidneys. Here, by fine-tuning the binding affinity of an antibody toward PV1, we observe that the anti-PV1 antibody with reduced binding affinity lost the capability for kidney targeting while retaining the lung targeting activity, suggesting that binding affinity is a critical factor for kidney targeting of the anti-PV1 antibody. We next use the antibody fragment F(ab')₂ targeting PV1 to assess the dual effects of rapid kidney filtration and PV1 targeting on kidney-selective targeting. Ex vivo fluorescence imaging results demonstrated that after rapidly accumulating in kidneys at 4 h, PV1-targeted F(ab')₂ was continually retained in the kidney at 24 h, whereas the isotype control F(ab')₂ underwent urinary elimination with significantly reduced signaling in the kidney. Confocal imaging studies confirmed the localization of PV1-targeted F(ab')₂ in the kidney. In addition, the monovalent antibody fragment (Fab-C4) lost the capability for kidney homing, indicating that the binding avidity of anti-PV1 F(ab')₂ is important for kidney targeting. Our findings suggest that PV1-targeted F(ab')₂ might be useful as a drug carrier for renal targeting and highlight the importance of affinity optimization for tissue targeting antibodies.

Targeting p16-induced senescence prevents cigarette smoke-induced emphysema by promoting IGF1/Akt1 signaling in mice

Senescence is a mechanism associated with aging that alters tissue regeneration by depleting the stem cell pool. Chronic obstructive pulmonary disease (COPD) displays hallmarks of senescence, including a diminished stem cell population. DNA damage from cigarette smoke (CS) induces senescence via the p16 pathway. This study evaluated the contribution of p16 to CS-associated lung pathologies. p16 expression was prominent in human COPD lungs compared with normal subjects. CS induces impaired pulmonary function, emphysema, and increased alveolar epithelial cell (AECII) senescence in wild-type mice, whereas CS-exposed p16-/- mice exhibit normal pulmonary function, reduced emphysema, diminished AECII senescence, and increased pro-growth IGF1 signaling, suggesting that improved lung function in p16-/- mice was due to increased alveolar progenitor cell proliferation. In conclusion, our study suggests that targeting senescence may facilitate alveolar regeneration in COPD emphysema by promoting IGF1 proliferative signaling.

Temporal trends and survivorship of total hip arthroplasty in very young patients

Aims

The aim of this study was to describe temporal trends and survivorship of total hip arthroplasty (THA) in very young patients, aged ≤ 20 years.

Patients and Methods

A descriptive observational study was undertaken using data from the National Joint Registry (NJR) for England, Wales, Northern Ireland and the Isle of Man between April 2003 and March 2017. All patients aged ≤ 20 years at the time of THA were included and the primary outcome was revision surgery. Descriptive statistics were used to summarize the data and Kaplan–Meier estimates calculated for the cumulative implant survival.

Results

A total of 769 THAs were performed in 703 patients. The median follow-up was 5.1 years (interquartile range (IQR) 2.6 to 7.8). Eight patients died and 35 THAs were revised. The use of metal-on-metal (MoM) bearings and resurfacing procedures declined after 2008. The most frequently recorded indications for revision were loosening (20%) and infection (20%), although the absolute risk of these events occurring was low (0.9%). Factors associated with lower implant survival were MoM and metal-on-polyethylene (MoP) bearings and resurfacing arthroplasty ( vs ceramic-on-polyethylene (CoP) and ceramic-on-ceramic (CoC) bearings, p = 0.002), and operations performed by surgeons who undertook few THAs in this age group as recorded in the NJR ( vs those with five or more recorded operations, p = 0.030). Kaplan–Meier estimates showed 96% (95% confidence interval (CI) 94% to 98%) survivorship of implants at five years.

Conclusion

Within the NJR, the overall survival for very young patients undergoing THA exceeded 96% during the first five postoperative years. In the absence of studies that can better account for differences in the characteristics of the patients, surgeons should consider the association between early revision and the type of implant, the number of THAs performed in these patients, and the bearing surface when performing THA in very young patients. Cite this article: Bone Joint J 2018;100-B:1320–9.

Direct measurements of temperature-dependent laser absorptivity of metal powders

A compact system is developed to measure laser absorptivity for a variety of powder materials (metals, ceramics, etc.) with different powder size distributions and thicknesses. The measured results for several metal powders are presented. The results are consistent with those from ray tracing calculations.

Size matters: how accurate is clinical estimation of traumatic wound size?

AIMS

The presentation of traumatic wounds is commonplace in the accident & emergency department. Often, these wounds need referral to specialist care, e.g. trauma & orthopaedic, plastic or maxillofacial surgeons. Documentation and communication of the size of the wound can influence management, e.g. Gustilo & Anderson classification of open fractures. Several papers acknowledge the variability in measurement of chronic wounds, but there is no data regarding accuracy of traumatic wound assessment. The authors hypothesised that the estimation of wound size and subsequent communication or documentation was often inaccurate, with high inter-observer variability. A study was designed to assess this hypothesis.

METHODS

A total of 7 scaled images of wounds related to trauma were obtained from an Internet search engine. The questionnaire asked 3 questions regarding mechanism of injury, relevant anatomy and proposed treatment, to simulate real patient assessment. One further question addressed the estimation of wound size. 50 doctors of varying experience across several specialities were surveyed. The images were analysed after data collection had finished to provide appropriate measurements, and compared to the questionnaire results by a researcher blinded to the demographics of the individual.

RESULTS

Our results show that there is a high inter-observer variability and inaccuracy in the estimation of wound size. This inaccuracy was directional and affected by gender. Male doctors were more likely to overestimate the size of wounds, whilst their female colleagues were more likely to underestimate size.

CONCLUSIONS

The estimation of wound size is a common requirement of clinical practice, and inaccurate interpretation of size may influence surgical management. Assessment using estimation was inaccurate, with high inter-observer variability. Assessment of traumatic wounds that require surgical management should be accurately measured, possibly using photography and ruler measurement.

Abstract 3917: Utilizing optical imaging technologies to screen candidate ADC antibodies

Antibody-drug conjugates (ADCs) represent a promising new therapeutic option to treat cancer where powerful cytotoxic compounds are conjugated to antibodies targeting a tumor-associated antigen. Molecular imaging allows relatively quick, non-invasive assessment of biological and biochemical processes in living subjects and when applied to research and development of ADC therapeutics, it has the potential to expedite the drug development process. The current study aims to evaluate optical imaging as a tool to aid in the selection of antibody candidates by using imaging data to predict in vivo efficacy of ADC therapeutics. In this study, candidate antibodies with engineered cysteines for site-specific conjugation of payloads were successfully labeled with the near-infrared fluorescent dye, alexa fluor 750, to achieve a degree of labeling of 2 dyes per antibody. Mice bearing target-positive tumors were treated with the dye-labeled antibodies, and were imaged at 1, 2, and 6 days post-injection using a fluorescence molecular tomography (FMT) in vivo imaging system. The tumor and major organs were subjected to ex vivo optical imaging and confirmatory immunofluorescence staining. Differences were observed in the tumor uptake, biodistribution profiles, and penetration of the four candidate antibodies. Concurrently, in vivo efficacy studies are being conducted with ADCs comprised of these lead antibodies, and the imaging data, along with the binding affinity and internalization rate of each antibody, will be compared to the pharmacology data to determine if a predictive correlation exists. Once established, correlations between the imaging data and efficacy results would justify the use of molecular imaging to screen large panels of antibodies to aid in the lead selection for ADCs, thus enabling significant time and cost reduction for the development of ADC therapeutics.

Citation Format: Xin Lin, Norman Peterson, George Wilson, Adeela Kamal, Jay Harper. Utilizing optical imaging technologies to screen candidate ADC antibodies. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3917. doi:10.1158/1538-7445.AM2013-3917

An objective assessment of safety to drive in an upper limb cast

Patients managed with upper limb cast immobilization often seek advice about driving. There is very little published data to assist in decision making, and advice given varies between healthcare professionals. There are no specific guidelines available from the UK Drivers and Vehicles Licensing Agency, police, or insurance companies. Evidence-based guidelines would enable clinicians to standardize the advice given to patients. Six individuals (three male, three female; mean age 36 years, range 27-43 years) were assessed by a mobility occupational therapist and driving standards agency examiner while completing a formal driving test in six different types of upper limb casts (above-elbow, below-elbow neutral, and below-elbow cast incorporating the thumb [Bennett's cast]) on both left and right sides. Of the 36 tests, participants passed 31 tests, suggesting that most people were able to safely drive with upper limb cast immobilization. However, driving in a left above-elbow cast was considered unsafe.

MEDI3617, a human anti-angiopoietin 2 monoclonal antibody, inhibits angiogenesis and tumor growth in human tumor xenograft models

Angiopoietin 2 (Ang2) is an important regulator of angiogenesis, blood vessel maturation and integrity of the vascular endothelium. The correlation between the dynamic expression of Ang2 in tumors with regions of high angiogenic activity and a poor prognosis in many tumor types makes Ang2 an ideal drug target. We have generated MEDI3617, a human anti-Ang2 monoclonal antibody that neutralizes Ang2 by preventing its binding to the Tie2 receptor in vitro, and inhibits angiogenesis and tumor growth in vivo. Treatment of mice with MEDI3617 resulted in inhibition of angiogenesis in several mouse models including: FGF2-induced angiogenesis in a basement extract plug model, tumor and retinal angiogenesis. In xenograft tumor models, treatment with MEDI3617 resulted in a reduction in tumor angiogenesis and an increase in tumor hypoxia. The administration of MEDI3617 as a single agent to mice bearing human tumor xenografts resulted in tumor growth inhibition against a broad spectrum of tumor types. Combining MEDI3617 with chemotherapy or bevacizumab resulted in a delay in tumor growth and no body weight loss was observed in the combination groups. These results, combined with pharmacodynamic studies, demonstrate that treatment of tumor-bearing mice with MEDI3617 significantly inhibited tumor growth as a single agent by blocking tumor angiogenesis. Together, these data show that MEDI3617 is a robust antiangiogenic agent and support the clinical evaluation and biomarker development of MEDI3617 in cancer patients.

Integrative medicine consultation with cancer patients: Does it affect patients concerns and well-being?

e20581

Background: Increased numbers of cancer patients are searching for additional options outside of their conventional medical care to improve their clinical outcome, quality of life, and overall wellbeing. Complementary and integrative medicine (CIM)) is one of the main options that patients are incorporating. The objectives of this study were to assess the outcome and value of an integrative medicine clinical consultation. Methods: Patients attending academic integrative medicine clinic evaluated their concerns and wellbeing using the Measure Yourself Concerns and Wellbeing (MYCaW) scale, a validated tool assessing outcome of complementary consultation for cancer patients. Prior to each visit patients completed the MYCaW and listed their two main concerns, the severity of the concern (0 = does not bother me at all to 6 = bothers me greatly), and their wellbeing (0 = as good as can be to 6 = as bad as can be). All patients met with a physician who provided an integrative consultation that included discussion of nutrition, supplements, exercise, useful complementary therapies, and the mind-body-spirit connection. At the follow up visit (usually 2–3 months later) patients completed the MYCaW to evaluate if the initial concerns were met. Results: Oncologists in the cancer center referred 197 patients for consultation about the integration of complementary medicine to their care. The majority of the participants were female (n=121), mean age was 56, range 21–90. Patients had been using a large range of CIM therapies including nutritional supplements (n=144), dietary changes (n=36), and acupuncture (n=33). The leading diagnosis was breast cancer followed by prostate cancer, but all major cancer diagnoses were represented. The leading concerns were related to “What else can I do?” and “How can I better cope?” From pre to post there was a reduction in severity of the concerns scores in 79% of patients, no change for 8%, and an increase for 13% (mean pre = 4.6; mean post = 2.6). For the question of Well being there was a reduction for 49%, no change for 32%, and an increase for 18% of the patients (mean pre = 2.5; mean post = 1.82). Conclusions: Integrative medicine consultations for cancer patients appear to be a valuable service that addresses patients’ main concerns and improves well being.

No significant financial relationships to disclose.

Chronic stress accelerates ultraviolet-induced cutaneous carcinogenesis

BACKGROUND

Physical and emotional stressors have been found to mediate a wide variety of biological changes including the facilitation of tumor progression; however most of these paradigms utilized artificial sources of neoplasms and stress.

METHODS

Skh mice were exposed to carcinogenic doses of ultraviolet light (UV). The stressed group was subjected to the close proximity of fox urine as a source of stress from the presence of the odor of their natural predator, while the control group remained stress free.

RESULTS

A significant acceleration in the development of cutaneous neoplasms was observed in mice that had been exposed to the stressor. The first tumor appeared in the group after 8 weeks, whereas nonstressed mice began to develop these by week 21.

CONCLUSION

These results suggest that stress plays a role in potentiating cutaneous carcinogenesis.

Fatal spotted fever rickettsiosis, Kenya

We report a fatal case of rickettsiosis in a woman from the United States living in Kenya, who had a history of tick exposure. Immunohistochemical staining of skin, kidney, and liver demonstrated spotted fever group rickettsiae. The clinical findings, severity, and fatal outcome are most consistent with Rickettsia conorii infection.

Effect of an intervention to reduce procedural pain and distress for children with HIV infection

OBJECTIVE

To evaluate a multicomponent pain management intervention, including cognitive behavioral strategies, for children with human immunodeficiency virus (HIV) infection undergoing routine venipuncture.

METHODS

Following a baseline venipuncture, children were exposed to an intervention including preparation, relaxation, distraction, reinforcement, parent involvement, and EMLA (eutectic mixture of local anesthetics) cream, and followed for three additional venipuncture procedures. After each procedure, child distress was rated on the Procedure Behavior Checklist (PBCL), child self-report of pain was obtained using the FACES scale, and parent anxiety was reported on the State Trait Anxiety Inventory-State Scale (STAI).

RESULTS

Significant reductions in child distress and pain were found by the second postintervention procedure and maintained at the third. Parent anxiety was significantly reduced by the second postintervention procedure, but many parents chose not to participate in the third postintervention procedure.

CONCLUSIONS

With repeated exposure, a multicomponent pain management intervention, including cognitive behavioral strategies and EMLA, appears effective at reducing pain, distress, and parent anxiety for children with HIV.

o-raffinose cross-linked hemoglobin improves the hemostatic defect associated with anemia and thrombocytopenia in rabbits

Several different preparations of cross-linked hemoglobin (CLHb) are being evaluated for their efficacy and safety as red cell substitutes in a variety of preclinical and clinical settings. Because CLHb is known to sequester nitric oxide (NO) and inhibit NO-mediated processes, we hypothesized that CLHb would have a hemostatic effect by enhancing platelet reactivity, inducing vasoconstriction, or both. Infusion of o-raffinose CLHb shortened the prolonged microvascular bleeding time and decreased blood loss from ear incisions in rabbits rendered anemic and thrombocytopenic. Moreover, this hemostatic effect persisted for at least 24 hours after infusion. Phenylephrine induced a degree of vasoconstriction similar to that induced by CLHb but did not shorten the bleeding time or decrease blood loss, suggesting that vasoconstriction alone cannot account for the hemostatic effect of CLHb. There was no evidence of CLHb-induced activation of coagulation in vivo, since infusion of CLHb did not increase circulating levels of thrombin-antithrombin complex. In vitro, CLHb abolished the inhibitory effect of the NO donor 3-morpholinosydnonimine on platelet aggregation and enhanced the aggregation of stimulated but not resting platelets. This potentiating effect was not attenuated by the addition of superoxide dismutase or catalase. To evaluate the potential arterial thrombogenicity of CLHb, a model of carotid artery thrombosis was developed in rabbits without thrombocytopenia or anemia. Compared with albumin infusion, CLHb infusion shortened the time to complete carotid occlusion. These data suggest that CLHb may shift the thromboregulatory balance toward clot formation, resulting in decreased bleeding in anemic and thrombocytopenic rabbits and possibly increasing arterial thrombogenicity in normal rabbits.

A comprehensive pediatric bereavement program: the patterns of your life

The death of a child is one of the most painful experiences a parent can endure. Communicating and meeting the needs of parents during this time of crisis is a challenge for nurses. Pediatric intensive care unit and emergency department nurses who may feel overwhelmed and inadequate when working with grieving families, especially with a sudden and unexpected death, are assisted by "The Patterns of Your Life: A Comprehensive Pediatric Bereavement Program." The program is a blending of critical pathways (an element of managed care), educational resources, and family follow-up for 1 year. Preliminary evaluations indicate that the comprehensive bereavement program appears to have many benefits for families and health care staff alike.

Crystal structure of a cross-reaction complex between Fab F9.13.7 and guinea fowl lysozyme

The crystal structure of the complex between the cross-reacting antigen Guinea fowl lysozyme and the Fab from monoclonal antibody F9.13.7, raised against hen egg lysozyme, has been determined by x-ray diffraction to 3-A resolution. The antibody interacts with exposed residues of an alpha-helix and surrounding loops adjacent to the lysozyme active site cleft. The epitope of lysozyme bound by antibody F9.13.7 overlaps almost completely with that bound by antibody HyHEL10; the same 12 residues of the antigen interact with the two antibodies. The antibodies, however, have different combining sites with no sequence homology at any of their complementarity-determining regions and show a dissimilar pattern of cross-reactivity with heterologous antigens. Side chain mobility of epitope residues contributes to confer steric and electrostatic complementarity to differently shaped combining sites, allowing functional mimicry to occur. The capacity of two antibodies that have different fine specificities to bind the same area of the antigen emphasizes the operational character of the definition of an antigenic determinant. This example demonstrates that degenerate binding of the same structural motif does not require the existence of sequence homology or other chemical similarities between the different binding sites.

Isoflurane anesthesia prevents unconscious learning

We investigated whether greater than or equal to 0.6 minimum alveolar concentration (MAC) of isoflurane suppresses learning of information presented verbally. Preoperatively, we asked 45 healthy patients (aged 23-58 yr) undergoing elective surgery 15 general knowledge questions designed to arouse their curiosity. They were told that they would be given the answers during anesthesia. Anesthesia was induced with isoflurane and nitrous oxide (25 subjects also received 1.1 +/- 0.6 mg/kg of propofol). The trachea was intubated with the aid of vecuronium (0.07 mg/kg IV). Isoflurane in oxygen was given to provide 0.6 MAC before and 1.0 and 1.4 MAC during surgery. After 10 min at each of two of the three MAC levels, the answers were given to five of the questions. At the remaining concentration, patients received a message to either touch an ear (n = 30) or keep their arms still (n = 15) during the postoperative interview. Twenty-four hours later, patients were asked whether they recalled intraoperative events. They were then asked to answer the 15 questions, choosing from five possible answers to each, one of which was correct. The number of times each patient touched an ear during this interview was noted. No patient consciously recalled events during anesthesia. The number of questions answered correctly postoperatively did not differ according to whether the answers had been provided during anesthesia (at any isoflurane concentration) or had not been provided (control questions). The number of ear-touches postoperatively did not differ between those who had and had not received the intraoperative message encouraging ear-touching.(ABSTRACT TRUNCATED AT 250 WORDS)

Desflurane does not produce hepatic or renal injury in human volunteers

We examined the potential toxicity of desflurane in 13 young 25.0 +/- 2.3 (mean +/- SD) yr-old men, given 7.35 +/- 0.81 MAC-hours of desflurane anesthesia. Hepatic and renal function tests, serum electrolytes, and standard urine and hematologic tests were performed before, during, and after anesthesia. No toxicity was found. There were no changes in tests of hepatocellular integrity (plasma alanine transferase activity), synthetic function (serum albumin, prothrombin time, partial thromboplastin time), or renal function (serum creatinine concentration, blood urea nitrogen concentration). Decreases in red blood cell count, hematocrit, and blood hemoglobin concentration during and immediately after anesthesia were attributed to blood sampling and infusion of intravenous electrolyte solution. These values returned by 4 days after anesthesia to values not different from those before anesthesia. Increased white blood cell counts and blood glucose concentrations noted during anesthesia with other inhaled anesthetics were also seen in these volunteers. Desflurane appears to have no greater toxicity than currently used inhaled anesthetics and, because of its lesser metabolism, may have lesser or not toxicity.

Cardiovascular actions of desflurane with and without nitrous oxide during spontaneous ventilation in humans

We investigated the cardiovascular actions of desflurane (formerly I-653) during spontaneous ventilation. We gave 0.8-0.9, 1.2-1.3, and 1.6-1.7 MAC desflurane in oxygen (n = 6) and in 60% nitrous oxide, balance oxygen (n = 6) to unmedicated healthy male volunteers. Both anesthetic regimens decreased ventilation, increased partial pressure of arterial carbon dioxide, and produced similar cardiovascular changes. In comparison with values obtained when the volunteers were conscious, desflurane anesthesia with spontaneous ventilation decreased systemic vascular resistance and mean arterial blood pressure. Cardiac index, heart rate, stroke volume index, and central venous blood pressure increased. Left ventricular ejection fraction increased at 0.83 MAC desflurane in oxygen, and otherwise did not differ from the conscious value. The velocity of ventricular circumferential fiber shortening, estimated by echocardiography, increased with desflurane in oxygen but did not change with desflurane in nitrous oxide. Oxygen consumption increased during desflurane and oxygen anesthesia, but not when nitrous oxide plus oxygen was the background gas. Desflurane increased oxygen transport, the ratio of oxygen transport to oxygen consumption, mixed venous partial pressure of oxygen, and oxyhemoglobin saturation. The cardiovascular changes with desflurane during spontaneous ventilation differ from those during controlled ventilation. With both background gases, spontaneous ventilation, in comparison with controlled ventilation, increased cardiac index, stroke volume, central venous pressure, left ventricular ejection fraction, velocity of circumferential fiber shortening, oxygen transport, and the ratio of oxygen transport to oxygen consumption but did not change mean arterial blood pressure except at 1.66 MAC desflurane in oxygen (when it was higher with spontaneous than with controlled ventilation).

Comparison of percutaneous losses of sevoflurane and isoflurane in humans

We studied the percutaneous losses of sevoflurane and isoflurane during administration and elimination in seven healthy male volunteers. Anesthesia was induced and maintained with fentanyl, midazolam, and/or thiopental, and nitrous oxide for 30 min, after which 1% sevoflurane and 0.4% isoflurane in 65% nitrous oxide were administered for 30 min. Inspired, end-tidal, and mixed-expired gas samples were collected during administration and for 5-7 days of elimination. To measure percutaneous loss, each subject's arm was enclosed in a glass cylinder sealed at both ends and with two ports, one for flushing with nitrogen and one for obtaining gas samples during the 30 min of administration and the first 150 min of elimination. Anesthetic concentrations in all samples were determined using gas chromatography. The surface area of the arm was measured and the total surface area was calculated. During administration and elimination, percutaneous loss of isoflurane was significantly greater than that of sevoflurane (P less than 0.05). For both volatile agents, losses during elimination were greater than during administration (P less than 0.05), but even when combined, these losses were too small to affect kinetic or metabolic studies based on mass balance.

Dot enzyme-linked immunosorbent assay (dot ELISA) for antibodies to Encephalitozoon cuniculi

A dot-ELISA procedure was developed to detect antibodies against Encephalitozoon cuniculi. Sera from 84 rabbits, 22 dogs, 18 squirrel monkeys and 200 mice were tested by dot-ELISA and most also were tested by immunofluorescence. Comparison of the two tests showed that there was excellent agreement of the results (Kappa values greater than or equal to 0.74) in all four species. Dot-ELISA is a simple, quantitative, rapid alternative to immunofluorescence when large numbers of serum samples must be evaluated.

Encephalitozoon cuniculi: quantitation of parasites and evaluation of viability

Two methods (manual and automated) for quantitation of viable versus dead Encephalitozoon cuniculi are reported. The manual method uses ethidium bromide and acridine orange to stain dead and viable organisms, respectively. The stained organisms are visually differentiated with the aid of a fluorescence microscope. The automated method uses propidium iodide to stain dead parasites, which are differentiated from viable unstained parasites with the aid of a flow cytometer. An automated cell counter (Coulter Counter) was used to count rapidly large numbers of samples and to improve the sensitivity of counting low concentrations of parasites. These methods will enhance investigators' abilities to conduct quantitative experiments on host defense mechanisms against E. cuniculi.

Pure primary testicular carcinoid: a case report and discussion

We report a case of pure primary testicular carcinoid tumor and review the literature. Distinctions are emphasized among the 3 subgroups of testicular carcinoids and their clinical significance. Criteria to establish the diagnosis of pure primary testicular carcinoid are offered.

Preoperative laparoscopic localization of the nonpalpable testis

Laparoscopic examination was performed successfully on 14 patients with 17 nonpalpable testes. The procedure was successful in determining the location in 16 of 17 nonpalpable testes, and this information was beneficial for selecting the subsequent operative approach. Laparoscopy was safe in the younger child (10 patients were 3 years old or less and 7 patients were less than 2 years old), and it added an insignificant increase in operative time.

Diagnosis and treatment of retroperitoneal perforation complicating the double-contrast barium-enema examination

A case of retroperitoneal air caused by rectal perforation during a double-contrast barium-enema examination is reported. In 9 similar reported cases, radiographic signs included perirectal, mediastinal, and cervical emphysema. Because of the frequent absence of clinical signs, radiographic recognition may be crucial for prompt management. Reported experience suggests that asymptomatic patients with these radiographic findings may be managed with hospitalization and close observation rather than immediate laparotomy.

Renal lymphoma simulating adult polycystic disease

Multiple cyst-like involvement of the kidney in a patient with lymphocytic lymphoma is presented. Both kidneys demonstrated the swiss-cheese appearance on nephrograms, simulating a typical adult type of polycystic disease. No tumor vessels or strains were noted.

Massive postpartum right renal hemorrhage

All reported cases of massive postpartum right renal hemorrhage have involved healthy young primigravidas and blacks have predominated (4 of 7 women). Coagulopathies and underlying renal disease have been absent. Hematuria was painless in 5 of 8 cases. Hemorrhage began within 24 hours in 1 case, within 48 hours in 4 cases and 4 days post partum in 3 cases. Our first case is the only report in which hemorrhage has occurred in a primipara. Failure of closure or reopening of pyelovenous channels is suggested as the pathogenesis. The hemorrhage has been self-limiting, requiring no more than 1,500 cc whole blood replacement. Bleeding should stop spontaneously, and rapid renal pelvic clot lysis should follow with maintenance of adequate urine output and Foley catheter bladder decompression. To date surgical intervention has not been necessary.

Obsidian Hydration Dating Applied to Dating of Basaltic Volcanic Activity

Basalt flows and bombs that contain remelted rhyolite glass can be dated by obsidian hydration dating.