Size distributions and mineralogy of ash particles in the stratosphere from eruptions of mount st. Helens.

Samples from the stratosphere obtained by U-2 aircraft after the first three major eruptions of Mount St. Helens contained large globules of liquid acid and ash. Because of their large size, these globules had disappeared from the lower stratosphere by late June 1980, leaving behind only smaller acid droplets. Particle-size distributions and mineralogy of the stratospheric ash grains demonstrate in-homogeneity in the eruption clouds.

Phase II study of oral idarubicin in favorable histology non-Hodgkin's lymphoma.

Idarubicin, a new analogue of daunorubicin, was administered p.o. for 3 consecutive days every 3 weeks at a dose of 45 mg/m2 in 46 patients (45 eligible and evaluable) with previously treated, favorable histology, non-Hodgkin's lymphoma. Median clinical characteristics included an age of 66 years, a performance status of 1, and one prior chemotherapeutic regimen. Forty-one patients were relapsing from prior therapy, and 37 had stage IV disease. Patients with prior anthracycline therapy were excluded. Responses were observed in 58% of patients (10 complete and 16 partial), with a median duration of 6+ months (2-41+ months). Idarubicin was well tolerated. Nonhematological toxicities (nausea/vomiting, mucositis/diarrhea, alopecia, and anorexia) were observed in less than or equal to 50% of patients. Median hematological values during the first cycle include a WBC of 4100/mm3 and a platelet count of 147,000/mm3. With dose escalation, hematological toxicity was the dose-limiting toxicity. Symptomatic cardiac toxicity was not observed. Median values for the resting left ventricular ejection fraction during the course of therapy were 0.65 (initial) and 0.63 (final). Idarubicin in oral form is an active drug in previously treated patients with favorable histology non-Hodgkin's lymphoma.

A neutral pH silver development method for the visualization of 1-nanometer gold particles in pre-embedding electron microscopic immunocytochemistry.

The availability of 1-nm gold particles permits the use of a particulate label with standard pre-embedding electron microscopic immunocytochemical techniques. We have employed these particles to localize a synaptic vesicle protein, p65, and a growth-associated protein, GAP-43, in neuron cell cultures. To be detected by standard transmission electron microscopy, these ultra-small gold particles must be enlarged. We have applied a commercially available silver development kit (IntenseM), the method of Danscher, and a neutral pH development procedure which we developed to effect this enlargement. Although IntenseM permits development with good preservation of morphology, it is limited by lack of reproducibility and by variability of final particle size. The method of Danscher provides well-controlled and reproducible enlargement, but is limited with respect to preservation of ultrastructural details. The neutral pH development procedure reproducibly enlarges gold particles with superior preservation of morphology. The use of this development procedure in conjunction with 1-nm gold probes should permit precise ultrastructural localization of a variety of intracellular antigens.

Silver enhancement of gold antibody probes in pre-embedding electron microscopic immunocytochemistry.

In pre-embedding EM immunocytochemistry with gold probes, the gold must be small enough to penetrate through cell membranes treated with mild detergents. Antibodies labeled with small gold probes (1-1.4 nm) are too small to be resolved in thin sections but can be seen if they are silver-enhanced after the gold has bound to the antigens in the cells. We investigated several aspects of gum arabic-silver lactate-hydroquinone enhancement solution (Danscher solution) by examining gold-conjugated antibodies embedded in agar, sectioned on a vibrotome, and enhanced with different solutions. The rate of silver enhancement was optimized in 50% gum arabic and 200 mM HEPES buffer, pH 5.8. We also examined chemicals used as developers and found that N-propyl gallate (NPG) gave a more uniform development than the routinely used hydroquinone (HQ). The diameter of the silver-enhanced particles after incubation in osmium tetratoxide (OSO4) decreased somewhat with longer incubation time and higher percentages, but the density (number per unit area) of silver-enhanced particles was little changed. The loss of silver-enhanced particle diameter was reduced by lowering the concentration of OSO4 to 0.1%. Comparison of commercial small gold probes showed that NPG enhancement of Nanogold gave more uniform particle size and a better correlation between enhancement time and particle density. When this procedure was applied to cell cultures with monoclonal antibodies, the silver-enhanced particles were similar to those in the agar sections. When free-floating tissue sections were used, longer silver enhancement times were needed to obtain similarly sized particles. This new NPG-silver-enhancement procedure offers a reliable and easy method to localize proteins in cultured cells and tissue sections by pre-embedding electron microscopic immunocytochemistry.

Alpha-1-antichymotrypsin is an effective inhibitor of pancreatitis-induced lung injury.

BACKGROUND: Pancreatitis-induced adult respiratory distress syndrome (ARDS) may result from an imbalance between leucocyte proteases, produced by infiltrating neutrophils, and endogenous protease inhibitors. OBJECTIVE: The aim of this study was to evaluate the role of recombinant alpha-1-antichymotrypsin (rACT P3-P3'), an endogenous serine protease inhibitor, in ameliorating lung injury associated with pancreatitis. DESIGN: Sprague-Dawley rats were randomly divided into control (saline infusion) and pancreatitis groups, which were treated immediately with saline or rACT P3-P3' (50 mg/kg body weight). METHODS: Myeloperoxidase (MPO) was employed as a monitor of neutrophil traffic in the lung, and wet-dry lung weights as a measure of pulmonary endothelial permeability. Lungs were also evaluated histologically. RESULTS: Caerulein (5 micrograms/kg body weight/h) induced pancreatitis in all animals, with an increase in serum amylase from 1851 +/- 208 IU (control) to 5198 +/- 924 IU (pancreatitis), P < 0.05. Pancreatitis caused a significant increase in MPO activity (7.8 +/- 1.1 units compared with 2.08 +/- 0.5 units in controls, P < 0.001) and wet-dry lung weight ratios (12.8 +/- 3.3 compared with 3.2 +/- 0.1 in controls, P < 0.001), indicating significant pulmonary neutrophil influx and microvascular leakage, respectively. These increases in MPO activity and wet-dry ratios were decreased in the pancreatitis group treated with rACT P3-P3' (MPO 4.68 +/- 0.7 units, wet-dry ratio 4.2 +/- 0.5, P < 0.05 compared with the untreated pancreatitis group). CONCLUSION: These data support the hypothesis that deficient endogenous protease inhibition may be responsible for the neutrophil-mediated lung injury observed in pancreatitis and suggest that there may be a therapeutic role for recombinant protease inhibitors such as alpha-1 antichymotrypsin.

Health promotion efforts in pennsylvania schools.

Abstract The purpose of this study was to investigate and describe health promotion efforts within Pennsylvania public schools. A questionnaire was designed which addressed the following areas: demographics, health issues and concerns, health promotion programming, and variables pertinent to describe districts without programs. The sample consisted of 275 superintendents of public school districts, 41 of which indicated the existence of a health promotion program in their district. Superintendents of districts with health promotion programs indicated the following: the most frequently offered programs were physical fitness activities, stress management and weight reduction; programs were most frequently offered during the after school hours; many programs were not open to family and community; and the administration of the programs was most frequently the responsibility of a school administrator. The remaining 234 school districts did not have health promotion programs. The reasons cited by the superintendents included limited financial resources, an uninterested faculty and staff, and lack of school board support.

Incendiary characteristics of a new laser-resistant endotracheal tube.

Endotracheal tube fires are the most frequent complication of laser surgery of the larynx. We investigated the incendiary characteristics of a new laser-resistant endotracheal tube, compared to polyvinyl chloride (PVC) and red rubber (RR) tubes, with different gas mixtures. A CO2 laser was focused on each tube and the probability of fire was assessed with oxygen fractions (FiO2) of 30%, 40%, 50%, 70%, and 100%, the balance being N2 or N2O. The laser-resistant tube could not be penetrated by a single laser pulse, regardless of laser energy or gas composition. PVC and RR tubes were readily ignited, the probability of ignition being related to oxygen concentration and laser energy. Nitrous oxide readily supported combustion. We suggest that laser surgery of the larynx can be most safely performed with a laser-resistant endotracheal tube and with gas mixtures containing the minimal safe O2 concentration (without nitrous oxide).

Self-esteem and health instruction: challenges for curriculum development.

A review of literature on self-esteem and its role in health education raises questions about the extent to which health education can influence student self-esteem through direct and indirect instruction. This article operationally defines self-esteem, discusses the role of health education in developing self-esteem through direct and indirect instruction, interprets evidence that self-esteem is affected by health education curricula, and discusses challenges facing health educators in curriculum development, instruction, and evaluation of self-esteem as a realistic component of health education curricula.

Contraceptive health programs for adolescents: a critical review.

Many adolescents are neither educated about contraception nor consistently practice it as part of their sexual health behavior. Contraceptive education has taken many forms and has been questioned as to its effectiveness. This paper reviews some of the contraceptive education programs that have been designed for adolescents. These programs, although targeting the adolescent population, differ in educational process based on the delivery setting. School-based, community-based, and college/university-based programs are reviewed and discussed in terms of their effectiveness, potential, and limitations. Educating adolescents about contraception should incorporate the cognitive, affective, and skill-based domains of learning, with outcome expectations based on the specific delivery setting. However, not all settings have the freedom to select from a variety of teaching methodologies. Thus, educational accountability in each setting should differ in terms of outcome expectations, particularly if the program evaluation includes behavioral components.

Homophobia within schools: challenging the culturally sanctioned dismissal of gay students and colleagues.

In this paper we chronicle the prevalence of and cultural prescription for homophobia in the United States. The endemic nature of homophobia as it has been studied by behavioral scientists is reviewed. We then suggest that as social institutions reflecting cultural values, schools, colleges, and universities sanction an environment that neglects the value of gay students, staff, and faculty. Institutional homophobia dismisses the legitimacy of these individuals, thereby minimizing their contributions to learning. Addressed specifically are suggestions for training individuals who work with students to recognize, address, and challenge homophobia. We conclude that while the weight of American culture sanctions homophobia, training educators and personnel about the nuances of institutional homophobia may provide a fairer environment for gay students and colleagues. An appendix of resources describing effective programs for educational and training use is provided.

Initial consecutive 125 cases of robotic assisted laparoscopic radical prostatectomy performed in Ireland's first robotic radical prostatectomy centre.

BACKGROUND: We examined the patient characteristics, operative proceedings and the outcomes of the initial series of 125 cases of robot-assisted laparoscopic radical prostatectomy (RALRP) in an independent hospital in Ireland, performed by two surgeons using the da Vinci(®) surgical system. MATERIALS AND METHODS: The series data were gathered prospectively in a consecutive series. Focus was given to the outcome trifecta of oncological control, urinary continence and erectile function. We also report on complications reported using the Clavien-Dindo classification. RESULTS: Mean patient age was 58.86 years, with a range between 47 and 71 years. Positive surgical margin rates were 11.3% overall (n = 14); 7.8% (n = 8) in the pT2 group (n = 101) and 30% (n = 6) in the pT3/pT4 (n = 20) group. 93% (n = 125) of patients are continent at 6 months. Biochemical recurrence-free survival was 92.4%. 72% (n = 43) of patients under the age of 65 with normal preoperative erectile function are potent at 1 year post-operatively. No patient in this series required a blood transfusion. Some form of relatively minor complication occurred in 12.8% (n = 16) of cases; there was no mortality rate, and no complication was life-threatening or resulted in single-organ or multiple-organ failure. CONCLUSIONS: With a combination of high-level fellowship training of surgeons, a co-operative and combined approach to cases between surgeons, institutional support, and enthusiasm, encouragement and dedication from ancillary staff and colleagues, we have shown that a programme can be established with excellent levels of safety and efficacy.