Praxic and nonverbal cognitive deficits in a large family with a genetically transmitted speech and language disorder

A pronounced speech and language disorder affecting half of the 30 members of the four-generational KE family has been attributed by some researchers to a specific defect in the generation of morphosyntactic rules. The reported selectivity of the impairment has led to the view that the affected members suffer from a grammar-specific disorder. Our investigations of the same KE family indicate that the inherited disorder has a broad phenotype which transcends impaired generation of syntactical rules and includes a striking articulatory impairment as well as defects in intellectual, linguistic, and orofacial praxic functions generally. Although the evidence from this family thus provides no support for the existence of "grammar genes," their linguistic difficulties do constitute a prominent part of their phenotype. Investigations of the neural and genetic correlates of their disorder could therefore uncover important clues to some of the bases of the primary human faculties of speech and language.

A DNA prime-modified vaccinia virus ankara boost vaccine encoding thrombospondin-related adhesion protein but not circumsporozoite protein partially protects healthy malaria-naive adults against Plasmodium falciparum sporozoite challenge

The safety, immunogenicity, and efficacy of DNA and modified vaccinia virus Ankara (MVA) prime-boost regimes were assessed by using either thrombospondin-related adhesion protein (TRAP) with a multiple-epitope string ME (ME-TRAP) or the circumsporozoite protein (CS) of Plasmodium falciparum. Sixteen healthy subjects who never had malaria (malaria-naive subjects) received two priming vaccinations with DNA, followed by one boosting immunization with MVA, with either ME-TRAP or CS as the antigen. Immunogenicity was assessed by ex vivo gamma interferon (IFN-gamma) enzyme-linked immunospot assay (ELISPOT) and antibody assay. Two weeks after the final vaccination, the subjects underwent P. falciparum sporozoite challenge, with six unvaccinated controls. The vaccines were well tolerated and immunogenic, with the DDM-ME TRAP regimen producing stronger ex vivo IFN-gamma ELISPOT responses than DDM-CS. One of eight subjects receiving the DDM-ME TRAP regimen was completely protected against malaria challenge, with this group as a whole showing significant delay to parasitemia compared to controls (P = 0.045). The peak ex vivo IFN-gamma ELISPOT response in this group correlated strongly with the number of days to parasitemia (P = 0.033). No protection was observed in the DDM-CS group. Prime-boost vaccination with DNA and MVA encoding ME-TRAP but not CS resulted in partial protection against P. falciparum sporozoite challenge in the present study.

Mortality among workers exposed to polychlorinated biphenyls

On the basis of evidence from animal studies, polychlorinated biphenyls (PCBs) are considered potentially carcinogenic to humans. However, the results of studies in human populations exposed to PCBs have been inconsistent. The authors conducted a retrospective cohort analysis (1957-1986) comparing the mortality of 3,588 electrical capacitor manufacturing workers with known exposure to PCBs with age-, sex-, and calendar time-specific mortality rates for all whites in the United States. Proportional hazards modeling was also performed to examine the association between cumulative PCB exposure and site-specific cancer mortality. All-cause mortality (192 deaths observed, 283.3 expected) and total cancer mortality (54 deaths observed, 63.7 expected) were lower than expected. More deaths were observed than expected for malignant melanoma (8 observed, less than 2.0 expected) and cancer of the brain and nervous system (5 observed, 2.8 expected). The average estimated cumulative dose for the cases of brain cancer (22.9 units) was greater than for other workers (12.9 units), but the 95% confidence intervals around this difference were broad. The risk of malignant melanoma was not related to cumulative PCB exposure. These results provide some evidence of an association between employment at this plant and malignant melanoma and cancer of the brain. The possibility that the results are due to chance, bias, or confounding cannot be excluded.

Pitch and timing abilities in inherited speech and language impairment

Members of the KE family who suffer from an inherited developmental speech-and-language disorder and normal, age-matched, controls were tested on musical abilities, including perception and production of pitch and rhythm. Affected family members were not deficient in either the perception or production of pitch, whether this involved either single notes or familiar melodies. However, they were deficient in both the perception and production of rhythm in both vocal and manual modalities. It is concluded that intonation abilities are not impaired in the affected family members, whereas their timing abilities are impaired. Neither their linguistic nor oral praxic deficits can be at the root of their impairment in timing; rather, the reverse may be true.

Low back pain-related beliefs and likely practice behaviours among final-year cross-discipline health students

BACKGROUND

Evidence points to clinicians' beliefs and practice behaviours related to low back pain (LBP), which are discordant with contemporary evidence. While interventions to align beliefs and behaviours with evidence among clinicians have demonstrated effectiveness, a more sustainable and cost-effective approach to positively developing workforce capacity in this area may be to target the emerging workforce. The aim of this study was to investigate beliefs and clinical recommendations for LBP, and their alignment to evidence, in Australian university allied health and medical students.

METHODS

Final-year students in chiropractic, medicine, occupational therapy, pharmacy and physiotherapy disciplines in three Western Australian universities responded to a survey. Demographic data, LBP-related beliefs data [modified Health Care Providers Pain and Impact Relationship Scale (HC-PAIRS) and the Back Pain Beliefs Questionnaire (BBQ)] and activity, rest and work clinical recommendations for an acute LBP clinical vignette were collected.

RESULTS

Six hundred two students completed the survey (response rate 74.6%). Cross-discipline differences in beliefs and clinical recommendations were observed (p > 0.001). Physiotherapy and chiropractic students reported significantly more helpful beliefs compared with the other disciplines, while pharmacy students reported the least helpful beliefs. A greater proportion of chiropractic and physiotherapy students reported guideline-consistent recommendations compared with other disciplines. HC-PAIRS and BBQ scores were strongly associated with clinical recommendations, independent to the discipline of study and prior experience of LBP.

CONCLUSIONS

Aligning cross-discipline university curricula with current evidence may provide an opportunity to facilitate translation of this evidence into practice with a focus on a consistent, cross-discipline approach to LBP management.

Original p53 status predicts for pathological response in locally advanced breast cancer patients treated preoperatively with continuous infusion 5-fluorouracil and radiation therapy

PURPOSE/OBJECTIVE

1) To test feasibility of preoperative continuous infusion (c.i.) 5-Fluorouracil (5-FU) and radiation (RT) in locally advanced breast cancer. 2) To study clinical and pathological response rates of 5-FU and radiation. 3) To attempt preliminary correlations between biological probes and pathological response.

METHODS AND MATERIALS

Previously untreated, locally advanced breast cancer patients were eligible: only patients who presented with T3/T4 tumors that could not be resected with primary wound closure were eligible, while inflammatory breast cancer patients were excluded. The protocol consisted of preoperative c.i. infusion 5-FU, 200 mg/m2/day with radiotherapy, 50 Gy at 2 Gy fractions to the breast and regional nodes. At mastectomy, pathological findings were classified based on persistence of invasive cancer: pathological complete response (pCR) = no residual invasive cells in the breast and axillary contents; pathological partial response (pPR) = presence of microscopic foci of invasive cells in either the breast or nodal specimens; no pathological response (pNR) = pathological persistence of tumor. For each patient pretreatment breast cancer biopsies were analyzed by immunohistochemistry for nuclear grade, ER/PR hormonal receptors, her2/neu and p53 overexpression.

RESULTS

Thirty-five women have completed the protocol and are available for analysis. 5-FU was interrupted during radiation in 10 of 35 patients because of oral mucositis in 8 patients, cellulitis in 1, and patient choice in another. Objective clinical response rate before mastectomy was 71% (25 of 35 patients): 4 CR, 21 PR. However, in all 35 patients tumor response was sufficient to make them resectable with primary wound closure. Accordingly, all patients underwent modified radical mastectomy: primary wound closure was achieved in all patients. At mastectomy there were 7 pCR (20%), 5 pPR (14%) and the remaining 23 patients (66%) had pathological persistence of cancer (pNR). Variables analyzed as potential predictors for pathological response (pPR and pCR) were: initial TNM clinical stage, clinical response, nuclear grade, hormonal receptor status, p53 overexpression, and Her2/neu overexpression in the pretreatment tumor biopsy. Only initial p53 status (lack of overexpression at immunohistochemistry) significantly correlated with achievement of a pathological response to this regimen (p = 0.010).

CONCLUSION

The combination of c.i. 5-FU and radiation was well tolerated and generated objective clinical responses in 71% of the patients. With the limitation of the small sample size, the complete pathological response achieved (20%) compares favorably with that reported in other series of neoadjuvant therapy for similar stage breast cancer. These preliminary data suggest that initial p53 status predicts for pathological response (pPR and pCR) to the combination of c.i. 5-FU and radiotherapy in locally advanced breast cancer.

Comparative study of infectious complications of different types of chronic central venous access devices

BACKGROUND

Various devices for central venous access are widely used in patients with cancer. The authors studied the incidence of infectious complications affecting these different devices.

METHODS

A retrospective study of 111 central venous access devices (VAD) placed in 1992 was conducted.

RESULTS

Subcutaneous ports were placed in 42 patients, single lumen Groshong catheters in 45, single lumen Hickman catheters in 15, double lumen Hickman catheters in 5, and double lumen Groshong catheters in 4. Prognostic factors analysis was performed with the log rank test and Cox's multivariate analysis. Different VAD types were compared with the likelihood ratio test. There was no significant difference in the risk of VAD-related infection between Hickman and Groshong catheters. Double lumen catheters were slightly more likely to cause infectious complications than single lumen catheters, although the difference was not statistically significant (P = 0.072 and 0.083 for bacteremia and site infection, respectively). No significant difference was observed in the risk of infection between subcutaneous ports and external catheters. Multivariate analysis using Cox's proportional hazards model demonstrated age younger than 50 years as the only significant risk factor, thus younger patients should be monitored more closely.

CONCLUSIONS

No significant difference was observed in the risk of infection between subcutaneous ports and external catheters. There was a slightly higher risk of infection in double lumen catheters than single lumen catheters, although the difference did not reach statistical significance. Considering the small sample size, the results should be confirmed in larger prospective studies.

Increased incidence of central venous catheter-related infections in bone marrow transplant patients

In view of an apparent increase of central venous catheter-related infections among our bone marrow transplant (BMT) patients, a retrospective study of infectious complications of central venous catheters was conducted. During 1992, 147 central venous catheters were placed in 133 patients. The overall infection rate of all catheters was 3.3 per thousand catheter-days (bacteremia 1.8, site infection 1.5). Patients scheduled for BMT had the highest infection rate of 11.5 (bacteremia 6.7, site infection 4.8). HIV patients had an infection rate of 6.6 per thousand catheter-days (bacteremia 3.8 and site infection 2.8) and patients with other diagnoses had a rate of 2.4 (bacteremia 1.3 and site infection 1.1). The difference of infection risk among the three groups is statistically significant (logrank p < .0001). In analyzing the 11 BMT patients more carefully, 14 catheters were placed. Of these, 9 catheters were removed, 8 (89%) of which were secondary to infection. Multivariate analysis showed that patients under 50 and BMT patients were more likely to develop catheter-related infection. While the cause of this complication is not known at present, the possible association with PBSC harvest is of much concern.

Supplemental Security Income (SSI), Disability Insurance (DI), and substance abusers

Federal legislation repealed Supplemental Security Income (SSI) and Disability Insurance (DI) for alcohol and drug abusers as of January 1997. This article outlines the context in which the legislation was passed and summarizes concerns resulting from the legislation. We discuss the effects of the legislation on treatment participation, financing, and availability, and the legislation's impact on individuals with dual mental health and substance abuse problems. We also consider the individual and societal implications of substance abusers' loss of monthly income and health insurance.

Global Burden of Animal Diseases: a novel approach to understanding and managing disease in livestock and aquaculture

Investments in animal health and Veterinary Services can have a measurable impact on the health of people and the environment. These investments require a baseline metric that describes the burden of animal health and welfare in order to justify and prioritise resource allocation and from which to measure the impact of interventions. This paper is part of a process of scientific enquiry in which problems are identified and solutions sought in an inclusive way. It poses the broad question: what should a system to measure the animal disease burden on society look like and what value would it add? Moreover, it aims to do this in such a way as to be accessible by a wide audience, who are encouraged to engage in this debate. Given that farmed animals, including those raised by poor smallholders, are an economic entity, this system should be based on economic principles. These poor farmers are negatively impacted by disparities in animal health technology, which can be addressed through a mixture of supply-led and demand-driven interventions, reinforcing the relevance of targeted financial support from government and non-governmental organisations. The Global Burden of Animal Diseases (GBADs) Programme will glean existing data to measure animal health losses within carefully characterised production systems. Consistent and transparent attribution of animal health losses will enable meaningful comparisons of the animal disease burden to be made between diseases, production systems and countries, and will show how it is apportioned by people's socio-economic status and gender. The GBADs Programme will produce a cloud-based knowledge engine and data portal, through which users will access burden metrics and associated visualisations, support for decisionmaking in the form of future animal health scenarios, and the outputs of wider economic modelling. The vision of GBADs, strengthening the food system for the benefit of society and the environment, is an example of One Health thinking in action.

The impact of the Women, Infants and Children Food Supplement Program on birth outcome

OBJECTIVE

Our purpose was to compare the birth outcomes of pregnant women in the Women, Infants and Children Food Supplement Program with women not in the program.

STUDY DESIGN

The vital records of 4713 women, 2895 enrolled in the Women, Infants and Children Food Supplement Program and 1812 not enrolled in the program, whose infants were delivered at Wishard Memorial Hospital over 18 months were reviewed with respect to age, education, race, substance habits, trimester of entry into prenatal care, maternal weight gain, and status in the program. The primary outcome variables evaluated were low birth weight, as defined by the delivery of an infant < 2500 gm, and infant mortality. The primary predictor was program participation versus nonparticipation. Analysis was by t test, chi2, and logistic regression models.

RESULTS

Black women, women with no prenatal care, and women who smoke were more likely to deliver a low-birth-weight infant. The incidence of low birth weight was 13.1% for nonparticipants versus 10.2% for program participants (p < 0.05). Univariate analysis confirmed program participants to be at significantly less risk for a low-birth-weight delivery (odds ratio = 0.75, p < 0.05). This relation, however, was not significant in the multivariate model (odds ratio = 0.88), indicating that the effect of participating in the program is being confounded by race, entry into prenatal care, and smoking. The overall infant mortality rate was 12.4 per 1000 for participants and 16 per 1000 for nonparticipants (p = not significant).

CONCLUSION

Nutritional and nonnutritional benefits to participation in the Women, Infants and Children Food Supplement Program were confirmed. Women enrolled in the program were less likely to deliver a low-birth-weight infant. Multiple variables likely contribute to the poorer outcome for nonparticipants.

Altered endochondral ossification in collagen X mouse models leads to impaired immune responses

Disruption of collagen X function in hypertrophic cartilage undergoing endochondral ossification was previously linked to altered hematopoiesis in collagen X transgenic (Tg) and null (KO) mice (Jacenko et al., [2002] Am J Pathol 160:2019-2034). Mice displayed altered growth plates, diminished trabecular bone, and marrow hypoplasia with an aberrant lymphocyte profile throughout life. This study identifies altered B220+, CD4+, and CD8+ lymphocyte numbers, as well as CD4+/fox3P+ T regulatory cells in the collagen X mice. Additionally, diminished in vitro splenocyte responses to mitogens and an inability of mice to survive a challenge with Toxoplasma gondii, confirm impaired immune responses. In concert, ELISA and protein arrays identify aberrant levels of inflammatory, chemo-attractant, and matrix binding cytokines in collagen X mouse sera. These data link the disruption of collagen X function in the chondro-osseous junction to an altered hematopoietic stem cell niche in the marrow, resulting in impaired immune function.

Oral Aversion in Infants With Congenital Heart Disease: A Single-Center Retrospective Cohort Study

OBJECTIVES

Neonates undergoing cardiac surgery are at risk for oral aversion (OA). OA is not well described outside of the index hospitalization and impacts patients and families. We evaluated the prevalence of OA at 1 year old after neonatal cardiopulmonary bypass (CPB) surgery.

DESIGN

Retrospective cohort study.

SETTING

Single quaternary care hospital.

SUBJECTS

Our cohort included 157 neonates who underwent CPB surgery from 2014 to 2017 and had follow-up data available at 1 year old.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Three feeding experts reviewed the medical record to define children with OA; 30% of charts were evaluated in triplicate for validation. Neonates with and without OA were compared in univariate analysis, and risk factors for OA were explored in a limited multivariable analysis. OA was present at 1 year in 37 patients (23.6%) and other feeding difficulties were present in an additional 29 patients (18.5%). Thirty-eight patients (24.2%) had a feeding tube, including 12 (7.6%) with a gastrostomy tube. Factors associated with OA at 1 year included total ICU days, duration of mechanical ventilation, total number of nil per os days, and number of postoperative days (PODs) until oral feeding initiation (all p < 0.0001). Number of POD until oral feeding initiation remained independently associated with OA at 1 year in multivariable analysis (adjusted odds ratio, 1.08; 95% CI, 1.04-1.12; p < 0.0001). Infants with any oral intake at discharge had lower odds of OA at 1 year (0.21; 95% CI, 0.08-0.5; p = 0.0003). At hospital discharge, 132 patients (84.1%) were taking some oral feeds, and 128 patients (81.5%) received tube feeding.

CONCLUSIONS

OA and other feeding difficulties are common at 1 year old in neonates undergoing CPB surgery. Delayed exposure to oral intake may be a modifiable risk factor for OA and efforts to improve early oral feeding could lead to better functional outcomes.

Fournier's gangrene with an unusual urologic etiology

Fournier's gangrene is a necrotizing infection affecting the male genitalia and perineum, caused by synergistic aerobic and anaerobic organisms. We report on a previously undescribed upper urinary tract etiology for this life-threatening infection.

Determination of organic acids in seven wheat varieties by capillary gas chromatography

Fresh wheat tops were extracted with acidic 90% ethanol, and the ethanol was evaporated and a portion of the aqueous residue loaded onto DEAE-Sephadex. Organic acids were eluted with pyridinium formate and then lyophilized and the dried residue was derivatized with 1% trimethylchlorosilane in bis(trimethylsilyl)trifluoroacetamide. The acids were then quantitatively determined using capillary gas chromatography and identified using capillary gas chromatography-mass spectrometry. The acidic ethanol extraction of fresh plant tissue was quantitative for all acids except citric while losses in the remaining procedures were controlled by using an internal standard. The ion exchange chromatography made the greatest contribution to experimental error, imposing a minimum loading requirement of 0.1 mumol of each acid for adequate precision. Organic acid profiles were determined for seven wheat cultivars (Triticum aestivum cv Carazinho, Teal, Lance, Warigal, Isis, Maringa, and BH1146) grown on gravel in solution culture for 30 days. Profiles were simple, consisting of only malic, aconitic, and citric acids, with levels of each acid for all varieties falling within the range 2-5 mumol/g fresh tissue. Storage of samples led to a large increase in sampling error and increased the amount of extractable citric acid.

Whole-brain metallomic analysis of the common marmoset (Callithrix jacchus)

Despite the importance of transition metals for normal brain function, relatively little is known about the distribution of these elemental species across the different tissue compartments of the primate brain. In this study, we employed laser ablation-inductively coupled plasma-mass spectrometry on PFA-fixed brain sections obtained from two adult common marmosets. Concurrent cytoarchitectonic, myeloarchitectonic, and chemoarchitectonic measurements allowed for identification of the major neocortical, archaecortical, and subcortical divisions of the brain, and precise localisation of iron, manganese, and zinc concentrations within each division. Major findings across tissue compartments included: (1) differentiation of white matter tracts from grey matter based on manganese and zinc distribution; (2) high iron concentrations in the basal ganglia, cortex, and substantia nigra; (3) co-localization of high concentrations of iron and manganese in the primary sensory areas of the cerebral cortex; and (4) high manganese in the hippocampus. The marmoset has become a model species of choice for connectomic, aging, and transgenic studies in primates, and the application of metallomics to these disciplines has the potential to yield high translational and basic science value.

Collagen mRNA content and distribution in the lungs of rats exposed to ozone

cDNAs, synthesized by the polymerase chain reaction (PCR) technique, were used to quantify mRNA concentrations for the alpha 1 (I) and alpha 1 (III) chains of collagen types I and III and for beta-actin in the lungs of rats exposed to either filtered air or to 1.2 ppm of ozone. The alpha 1 (I) procollagen mRNA concentration was increased by about 30% in the lungs of rats exposed to ozone, while the concentrations of the mRNAs for alpha 1 (III) procollagen and for beta-actin were the same in the lungs of control and ozone-exposed animals. The lungs from the rats exposed to 1.2 ppm of ozone preferentially synthesized type I collagen as compared with controls. Sites of increased expression of the alpha 1 (I) procollagen mRNA were detected by in situ hybridization in lung sections embedded in paraffin prepared from rats exposed either to filtered air or to ozone. The lungs from rats treated with ozone focally expressed increased amounts of alpha 1 (I) procollagen mRNA in the lung parenchyma at the septal tips and the bronchiole-alveolar duct junctions. They also showed an apparent diffuse increase in alpha 1 (III) procollagen mRNA expression. We conclude that exposure of rats to high concentrations of ozone causes a specific increase in the lung content of mRNA for the major chain of type I collagen.

Cyclo-oxygenase blockade abrogates the endotoxin-induced increase in Na(+)-dependent hepatic amino acid transport

BACKGROUND

Endotoxemia is characterized by a marked increase in the uptake of amino acids by the liver, but the regulation of this response has not been fully elucidated. In the current study, we investigated the potential role of prostaglandins as mediators of this response. We examined the in vivo effects of the anti-inflammatory agent ketorolac, a cyclo-oxygenase inhibitor that blocks prostaglandin synthesis, on hepatic amino acid transport activity in endotoxin-treated rats.

METHODS

We assayed the activities of the Na(+)-dependent transport systems A and N in hepatic plasma membrane vesicles prepared from endotoxemic rats that were pretreated with ketorolac or vehicle. Hepatic plasma membrane vesicles were prepared by differential centrifugation, and the transport of [3H]glutamine (system N) and [3H]2-methylamino-isobutyric acid (system A) was assayed. Hepatic plasma membrane vesicles were also prepared from normal rats that received prostaglandin E2, and glutamine and MeAIB transport were measured.

RESULTS

Endotoxin treatment resulted in a twofold to threefold increase in Na(+)-dependent amino acid transport activity in hepatic plasma membrane vesicles secondary to an increase in the transport Vmax, which was consistent with the appearance of increased numbers of corresponding transporter proteins in the hepatocyte plasma membrane. Pretreatment with ketorolac almost completely abrogated the endotoxin-induced increase in hepatic amino acid transport. Administration of prostaglandin E2 to normal rats resulted in a statistically significant increase in glutamine and alanine transport by hepatic plasma membrane vesicles prepared from these animals.

CONCLUSIONS

Prostaglandins play a key role in mediating the accelerated hepatic amino acid transport that occurs during endotoxemia.

Vaccine safety surveillance in Canada: Reports to CAEFISS, 2013-2016

BACKGROUND

Canada has one of the strongest vaccine safety surveillance systems in the world. This system includes both passive surveillance of all vaccines administered and active surveillance of all childhood vaccines.

OBJECTIVES

To provide 1) a descriptive analysis of the adverse events following immunization (AEFI) reports for vaccines administered in Canada, 2) an analysis of serious adverse events (SAEs) and 3) a list of the top ten groups of vaccines with the highest reporting rates.

METHODS

Descriptive analyses were conducted of AEFI reports received by the Public Health Agency of Canada (PHAC) by August 14, 2017, for vaccines marketed in Canada and administered from January 1, 2013 to December 31, 2016. Data elements in this analysis include: type of surveillance program, AEFIs, demographics, health care utilization, outcome, seriousness of adverse events and type of vaccine.

RESULTS

Over the four year period, 11,079 AEFI reports were received from across Canada. The average annual AEFI reporting rate was 13.4/100,000 doses distributed in Canada for vaccines administered during 2013-2016 and was found to be inversely proportional to age. The majority of reports (92%) were non-serious events, involving vaccination site reactions rash and allergic events. Overall, there were 892 SAE reports, for a reporting rate of 1.1/100,000 doses distributed during 2013-2016. Of the SAE reports, the most common primary AEFIs were anaphylaxis followed by seizure. Meningococcal serogroup C conjugate vaccines (given concomitantly) were responsible for the highest rates of AEFIs, at 91.6 per 100,000 doses distributed. There were no unexpected vaccine safety issues identified or increases in frequency or severity of expected adverse events.

CONCLUSION

Canada's continuous monitoring of the safety of marketed vaccines during 2013-2016 did not identify any increase in the frequency or severity of AEFIs, previously unknown AEFIs, or areas that required further investigation or research. Vaccines marketed in Canada continue to have an excellent safety profile.

Laser removal of oxides and particles from copper surfaces for microelectronic fabrication

Laser removal of surface oxides and small particles from copper surfaces was carried out using a Q-switched Nd:YAG laser. Oxide layers and small particles on copper surfaces should be removed for the improvement of solder quality on printed circuit boards (PCBs) and for the prevention of circuit failure or loss of production yield during the fabrication of microelectronic devices. A selective removal of surface oxides from a copper surface was achieved by the laser treatment, which was confirmed by on-line acoustic monitoring of the process. An angular laser cleaning technique in which the laser irradiates the surface at a glancing angle was used for effective removal of the particles from the surface. The unique characteristics of this technique and the cleaning mechanism are discussed.

Centriacinar remodeling and sustained procollagen gene expression after exposure to ozone and nitrogen dioxide

Sprague-Dawley rats were exposed to 0.8 ppm ozone (O3), to 14.4 ppm nitrogen dioxide (NO2), or to both gases simultaneously for 6 h per day for up to 90 d. The extent of histopathologic changes within the central acinus of the lungs was compared after 7 or 78 to 90 d of exposure using morphometric analysis by placement of concentric arcs radiating outward from a single reference point at the level of the bronchiole- alveolar duct junction. Lesions in the lungs of rats exposed to the mixture of gases extended approximately twice as far into the acinus as in those exposed to each individual gas. The extent of tissue involvement was the same at 78 to 90 d as noted at 7 d in all exposure groups. At the end of exposure, in situ hybridization for procollagen types I and III demonstrated high levels of messenger RNA within central acini in the lungs of animals exposed to the combination of O3 and NO2. In contrast, animals exposed to each individual gas had a similar pattern of message expression compared with that seen in control animals, although centriacinar histologic changes were still significantly different from control animals. We conclude that the progressive pulmonary fibrosis that occurs in rats exposed to the combination of O3 and NO2 is due to sustained, elevated expression of the genes for procollagen types I and III. This effect at the gene level is correlated with the more severe histologic lesions seen in animals exposed to both O3 and NO2 compared with those exposed to each individual gas. In contrast, the sustained expression of the procollagen genes is not associated with a shift in the distribution of the lesions because the area of change in each group after 7 d of exposure was the same as after 78 to 90 d of exposure.