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PubMed2006

UMTS base station-like exposure, well-being, and cognitive performance.

BACKGROUND: Radio-frequency electromagnetic fields (RF EMF) of mobile communication systems are widespread in the living environment, yet their effects on humans are uncertain despite a growing body of literature. OBJECTIVES: We investigated the influence of a Universal Mobile Telecommunications System (UMTS) base station-like signal on well-being and cognitive performance in subjects with and without self-reported sensitivity to RF EMF. METHODS: We performed a controlled exposure experiment (45 min at an electric field strength of 0, 1, or 10 V/m, incident with a polarization of 45 degrees from the left back side of the subject, weekly intervals) in a randomized, double-blind crossover design. A total of 117 healthy subjects (33 self-reported sensitive, 84 nonsensitive subjects) participated in the study. We assessed well-being, perceived field strength, and cognitive performance with questionnaires and cognitive tasks and conducted statistical analyses using linear mixed models. Organ-specific and brain tissue-specific dosimetry including uncertainty and variation analysis was performed. RESULTS: In both groups, well-being and perceived field strength were not associated with actual exposure levels. We observed no consistent condition-induced changes in cognitive performance except for two marginal effects. At 10 V/m we observed a slight effect on speed in one of six tasks in the sensitive subjects and an effect on accuracy in another task in nonsensitive subjects. Both effects disappeared after multiple end point adjustment. CONCLUSIONS: In contrast to a recent Dutch study, we could not confirm a short-term effect of UMTS base station-like exposure on well-being. The reported effects on brain functioning were marginal and may have occurred by chance. Peak spatial absorption in brain tissue was considerably smaller than during use of a mobile phone. No conclusions can be drawn regarding short-term effects of cell phone exposure or the effects of long-term base station-like exposure on human health.

Adult↗
PubMedDate not supplied

[HIV, HBV, or HCV transmission from infected health care workers to patients].

BACKGROUND: The report of transmission of viruses, such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV), from health care workers (HCWs) to patient has alarmed public opinion with potential repercussions on health organisation. OBJECTIVES: To review available information on cases of transmission of HIV, HBV and HCV from HCW to patient reported worldwide. METHODS: A literature review was conducted with a Medline search of English language full papers, using the following key terms: HIV, HBV, HCV; healthcare workers, occupational and hospital transmission, outbreak, look back investigation. The Medline search was supplemented by a manual search using reference lists of published studies and proceedings of meetings, including some personal communications already reported in a previous review. RESULTS: Since 1972, 50 outbreaks have been reported in which 48 HBV infected HCWs (39 surgeons) transmitted the infection to approximately 500 persons. To date, 3 cases of transmission of HIV and 8 confirmed cases of transmission of HCV (to a total of 18 patients) from infected healthcare workers to patients have been reported. The factors influencing the transmissibility of infection include: type of procedures performed, surgical techniques used, compliance with infection control precautions, the clinical status and viral burden of the infected HCW and susceptibility of the patient to infection. The risk of transmission of HIV, HBV and HCV from HCWs to patients is associated primarily with certain types of surgical specialties (obstetrics and gynaecology, orthopaedics, cardiothoracic surgery) and surgical procedures that can expose the patient to the blood of the HCW: exposure-prone procedures. Since the early 90's industrialized countries have issued recommendations for preventing transmission of blood-borne pathogens to patients during "exposure prone" invasive procedures. With regard to HBV there is common consent to restricting or excluding HCWs tested HbeAg positive or HBV DNA-positive from performing exposure-prone procedures, while there are still some discrepancies in the different countries for dealing with HCV-infected personnel and in some cases also for those with HIV infection. CONCLUSIONS: Efforts to prevent surgeon-to-patient transmission of blood-borne infections should focus not only on ascertaining the infection status of the HCW but principally on eliminating the cause of blood-borne exposures, for example by the use of blunt suture needles, improved instruments, reinforced gloves, changes in surgical technique and the use of less invasive alternative procedures. These measures should be implemented in order to minimize the risk of blood exposure and consequently of virus transmission both to and from HCW to patients.

HIV Infections↗
PubMedDate not supplied

Managing holistic improvement.

In the rush to stay in tune with the rapid pace of change, many organizations are now implementing total quality management (TQM)--often without first examining whether they are ready to take full advantage of what this approach has to offer. Indeed, if TQM is implemented as a quick fix (for example, getting everyone involved in learning tools and techniques, forming continuous improvement teams across departments and disciplines, and then expecting all employees to make significant improvements in the way they serve their customers) when, in fact, there is mistrust, defensive communication, little teamwork across work units, conflicting strategic signals, fragmented organizational structures, and a reward system that ignores performance, virtually any TQM program is likely to fail. Rather than putting more and more pressure on employees to improve--when they cannot because of all these roadblocks--organizations might first consider identifying and then removing their systemic barriers to success with a completely integrated program. Once the necessary foundation for TQM has been established, all employees will be able--and willing--to work together to improve their processes, products, and services for the benefit of their customers.

Decision Making, Organizational↗
PubMedDate not supplied

[Echocardiography diagnosis of total anomalous pulmonary venous drainage in the neonatal period].

A 20-days-old female newborn was referred to our hospital because of persistent respiratory distress and a mild central cyanosis. On echocardiography from the suprasternal notch all 4 pulmonary veins could be visualized entering a common chamber posterior to the left atrium. This chamber communicated with a left vertical vein which drained through a large innominate vein into the right superior vena cava. The diagnosis of supracardiac type of TAPVD was confirmed the following day by angiography. The child was successfully operated and the postoperative course was uneventful. Cardiac catheterization carries an increased risk in patients with TAPVD in case of pulmonary hypertension due to pulmonary-venous obstruction. In experienced centers echocardiography has become the definite diagnostic method with a high level of sensitivity and specificity in patients with atrial sitlus solitus, unifocal pulmonary venous connection, and no evidence of other major congenital cardiac defects. With continuously improving knowledge an increasing number of newborns will benefit from improved ability to perform surgical repair without prior cardiac catheterization.

Blood Flow Velocity↗
PubMed1985

The Cronin push-back palate repair with nasal mucosal flaps: a speech evaluation.

This is a retrospective study of 92 cleft palate patients who had been repaired with the Cronin push-back palate repair with nasal mucosal flaps. The patients were evaluated by a speech pathologist for intelligibility, articulation, and resonance and rated using a 5-point scale devised for this study. Readily intelligible speech was present in 78 percent. Normal articulation was present in 66 percent. Normal resonance was present in 78 percent of the total subject group. Secondary procedures were performed in 14 percent of the group. Repaired clefts of the soft palate achieved a high rate of normal intelligibility, articulation, and resonance. Repaired submucous clefts and short palates achieved the lowest percent of normal articulation and resonance. Educational placement, hearing, and type of structural deformity all appear to influence the ultimate communication outcome.

Child↗
PubMed2006

Exposure of rat brain to 915 MHz GSM microwaves induces changes in gene expression but not double stranded DNA breaks or effects on chromatin conformation.

We investigated whether exposure of rat brain to microwaves (MWs) of global system for mobile communication (GSM) induces DNA breaks, changes in chromatin conformation and in gene expression. An exposure installation was used based on a test mobile phone employing a GSM signal at 915 MHz, all standard modulations included, output power level in pulses 2 W, specific absorption rate (SAR) 0.4 mW/g. Rats were exposed or sham exposed to MWs during 2 h. After exposure, cell suspensions were prepared from brain samples, as well as from spleen and thymus. For analysis of gene expression patterns, total RNA was extracted from cerebellum. Changes in chromatin conformation, which are indicative of stress response and genotoxic effects, were measured by the method of anomalous viscosity time dependencies (AVTD). DNA double strand breaks (DSBs) were analyzed by pulsed-field gel electrophoresis (PFGE). Effects of MW exposure were observed on neither conformation of chromatin nor DNA DSBs. Gene expression profiles were obtained by Affymetrix U34 GeneChips representing 8800 rat genes and analyzed with the Affymetrix Microarray Suite (MAS) 5.0 software. In cerebellum from all exposed animals, 11 genes were upregulated in a range of 1.34-2.74 fold and one gene was downregulated 0.48-fold (P < .0025). The induced genes encode proteins with diverse functions including neurotransmitter regulation, blood-brain barrier (BBB), and melatonin production. The data shows that GSM MWs at 915 MHz did not induce PFGE-detectable DNA double stranded breaks or changes in chromatin conformation, but affected expression of genes in rat brain cells.

Animals↗
PubMed2001

Doctors' and nurses' perceptions of ethical problems in end-of-life decisions.

AIMS: To identify and compare doctors' and nurses' perceptions of ethical problems. Rationale. Ethical problems are a source of tension for health professionals. Misunderstandings or conflicts may result from differing perceptions of ethical problems. If true collaboration is to be achieved, it is important to understand the perspectives of others, particularly when difficult end-of-life decisions must be made. METHODS: In this qualitative study a total of seven doctors and 14 nurses working in acute care adult medical-surgical areas, including intensive care, were asked to describe ethical problems that they frequently encounter in practice. Interviews were taped and transcribed. Thematic analysis followed. RESULTS: All participants experienced ethical problems around decision making at the end of life. The core problem for both doctors and nurses was witnessing suffering, which engendered a moral obligation to reduce that suffering. Uncertainty about the best course of action for the patient and family was a source of moral distress. Competing values, hierarchical processes, scarce resources, and communication emerged as common themes. The key difference between the groups was that doctors are responsible for making decisions and nurses must live with these decisions. Each group, therefore, asked different questions when encountering and interpreting sources of moral distress. CONCLUSIONS: It was concluded that observed differences between doctors and nurses were a function of the professional role played by each rather than differences in ethical reasoning or moral motivation. Although this was a small qualitative study on one institution, and may not be generalizable, results suggest that doctors and nurses need to engage in moral discourse to understand and support the ethical burden carried by the other. Administrators should provide opportunities for discourse to help staff reduce moral distress and generate creative strategies for dealing with this.

Adult↗
PubMed2002

Chronic suicidality among patients with borderline personality disorder.

OBJECTIVE: This paper reviews research on chronic suicidality among patients with borderline personality disorder. METHODS: MEDLINE and PsycINFO databases were searched for all English-language articles published between 1984 and 2000 containing the keywords "borderline personality disorder" and "suicide" or "suicidality." A total of 170 articles located through this search and additional key articles published before 1990 were reviewed. The most relevant articles were selected of review. RESULTS AND CONCLUSIONS: One in ten patients with borderline personality disorder completes suicide, but this outcome is not readily preventable and does not necessarily occur during the course of treatment. In outpatient psychotherapy, chronic suicidal behavior by patients with borderline personality disorder can be best understood as a way of communicating distress. Hospitalization is of unproven value in preventing suicide by these patients and can sometimes have negative effects. Clinicians' fear of potential litigation resulting from a completed suicide should not be the basis for admission. With no evidence that full hospitalization prevents suicide completion by patients with borderline personality, suicidal risk is not a contraindication for day hospital treatment.

Borderline Personality Disorder↗
PubMed2000

Health-related quality of life in patients treated with temozolomide versus procarbazine for recurrent glioblastoma multiforme.

PURPOSE: To determine whether chemotherapy with temozolomide (TMZ) versus procarbazine (PCB) for recurrent glioblastoma multiforme (GBM) was associated with improvement in health-related quality of life (HRQOL). PATIENTS AND METHODS: HRQOL was assessed at baseline and during treatment using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 and a Brain Cancer Module (BCM20) in two clinical trials that enrolled a total of 366 patients. Two hundred eighty-eight patients provided HRQOL data that could be used for analysis; 109 patients received TMZ in a phase II study, whereas 89 patients received TMZ and 90 received PCB in a randomized phase III study. Changes from baseline in the scores of seven preselected HRQOL domains (role and social functioning, global quality of life [QOL], visual disorders, motor dysfunction, communication deficit, and drowsiness) were calculated for all groups. Statistical significance, effect sizes, and proportions of patients with improved HRQOL scores (changes of > or = 10 points) were calculated. RESULTS: Before disease progression, patients treated with TMZ were found to have an improvement in most of the preselected HRQOL domain scores compared with their baseline (pretreatment) scores. Those who were progression-free on TMZ at 6 months had improvement in all the preselected HRQOL domains. Conversely, patients treated with PCB reported deterioration in HRQOL that was independent of whether or not the disease had progressed by 6 months. Patients with disease progression, regardless of treatment, experienced a sharp decline in all domains at the time of progression. CONCLUSION: Treatment with TMZ was associated with improvement in HRQOL scores compared with treatment with PCB. The deterioration reported by PCB-treated patients was likely because of toxicity. Delaying disease progression by treatment with TMZ is beneficial to the HRQOL status of patients with recurrent GBM.

Adult↗
PubMedDate not supplied

Emerging issues associated with HIV patients seeking advice from health food stores.

OBJECTIVES: To ascertain the recommendations, training and education of health food store employees and determine how they communicate the costs, benefits and risks associated with natural health products for the HIV/AIDS community. METHODS: Four male research assistants, posing as asymptomatic HIV-positive individuals, inquired of employees of all retail health food stores in a major Canadian city as to what is recommended for their condition. The research assistants asked about product costs, side effects, potential drug interactions and efficacy. They also inquired as to employee education related to Complementary and Alternative Medicine (CAM) and noted whether employees asked about which conventional medications they were taking and whether they recommended that the subjects seek physician or CAM provider advice. RESULTS: A total of 32 stores were included. Eight store employees (25%) offered no advice; eight (25%) inquired whether the subjects were currently taking medications; six (19%) suggested visiting a physician; and eight (25%) suggested visiting a CAM provider. A total of 36 different products (mean 2.3 per employee) were recommended with considerable variability in product evidence and cost. The education of the employees varied from postgraduate education (n=3), to undergraduate degree (n=3), college level (n=5) in CAM, or no formal education in CAM (n=21). CONCLUSION: There was considerable heterogeneity in advice on natural food products provided by employees of natural food stores and, in general, these individuals had limited formal training in CAM. The products they recommended had limited evidence supporting their efficacy and in some instances were potentially harmful and had considerable costs. The findings of this study support the need to further examine how best to regulate this growing component of the health care system.

Canada↗
PubMed2005

ATP release through connexin hemichannels in corneal endothelial cells.

PURPOSE: Intercellular Ca(2+) wave propagation is a distinct form of cell-cell communication. In corneal endothelial cells, intercellular Ca(2+) wave propagation evoked by a point mechanical stimulus (PMS) is partially mediated by adenosine triphosphate (ATP) release and subsequent activation of P2Y receptors. This study was conducted to investigate the possibility that extrajunctional connexons (hemichannels) play a role in ATP release during PMS-induced Ca(2+) wave propagation in bovine corneal endothelial cells (BCECs). METHODS: A Ca(2+) wave was evoked by a PMS applied to a single cell in a monolayer of cultured BCECs. Changes in [Ca(2+)](i) in the mechanically stimulated cell (MS cell) and in the neighboring (NB) cells were visualized by fluorescence imaging using the Ca(2+)-sensitive dye Fluo-4. From these images, the maximum normalized fluorescence (NF), the percentage of responsive cells (%RC), and the total area of cells reached by the Ca(2+) wave (active area [AA], in square micrometers) were calculated. Intercellular dye transfer, generally attributed to gap junctional coupling, was assessed by fluorescence recovery after photobleaching (FRAP) using 6-carboxyfluorescein diacetate. Opening of hemichannels was investigated by measuring cellular uptake of the fluorescent dye Lucifer yellow, which is known to permeate hemichannels. ATP release was measured by luciferin-luciferase bioluminescence. RESULTS: Flufenamic acid (FFA; 50 microM) and the connexin mimetic peptide Gap26 (300 microM), known blockers of hemichannels, significantly reduced AA in confluent monolayers as well as in contact-free cells. Neither FFA nor Gap26 affected the FRAP, indicating that reduction in AA of the PMS-induced wave by these agents is not due to a block of gap junction channels. FFA as well as Gap26 inhibited the increase in AA of the wave that was observed when cells were pretreated with the ectonucleotidase inhibitor ARL-67156 (100 microM). These findings suggest that the hemichannel blockers reduce the Ca(2+) wave propagation by inhibiting ATP release. Consistent with this finding, PMS or exposure to Ca(2+)-free solution (a maneuver known to induce the opening of hemichannels) led to ATP release; moreover, the release was inhibited by the hemichannel blockers. The extracellular ATP levels in response to both PMS and extracellular Ca(2+) removal were strongly enhanced by ARL-67156, and this effect was inhibited by FFA as well as by Gap26. Moreover, pretreatment of subconfluent BCEC monolayers with FFA or Gap26 inhibited the uptake of Lucifer yellow induced by removal of extracellular Ca(2+). CONCLUSIONS: Hemichannels contribute to ATP release on mechanical stimulation in BCECs. The released ATP contributes to propagation of the Ca(2+) wave.

Adenosine Triphosphate↗
PubMed1999

Laser scanning analysis of cell-cell communication in cultured human prostate tumor cells.

OBJECTIVE: To investigate gap-junctional intercellular communication (GJIC) in LNCaP and DU145 human prostate cancer cells. STUDY DESIGN: Normal rat liver F344 (WB1) cells were used as positive controls. Functional GJIC was inspected using either the scrape-loading/dye transfer (SL/DT) method or fluorescence recovery after photobleaching (FRAP) analysis. In the former, GJIC activity was expressed as a measure of the extent of diffusion of Lucifer Yellow after cell monolayers were scraped using a surgical blade and exposed to dye for a few minutes at room temperature. In the latter, cells were incubated for 15 minutes at 37 degrees C with 5,6-carboxyfluorescein diacetate dye and the dye transfer visualized by photobleaching individual cells with a 488-nm laser and monitoring the recovery of fluorescence using a laser cytometer. RESULTS: The preliminary results obtained indicate that neither LNCaP nor DU145 cells have functional GJIC, while, as expected, WB1 cells show unimpaired GJIC activity. Equivalent results were consistently obtained using either SL/DT or the FRAP approach. However, using FRAP analysis, DU145 cells only showed weak recovery of fluorescence after a total observation interval of 15 minutes. CONCLUSION: The present data, though preliminary, suggest that disruption of GJIC may play a role in development of malignancy in the human prostate.

Animals↗
PubMed2005

Improved assessment of denitrifying, N2-fixing, and total-community bacteria by terminal restriction fragment length polymorphism analysis using multiple restriction enzymes.

A database of terminal restriction fragments (tRFs) of the 16S rRNA gene was set up utilizing 13 restriction enzymes and 17,327 GenBank sequences. A computer program, termed TReFID, was developed to allow identification of any of these 17,327 sequences by means of polygons generated from the specific tRFs of each bacterium. The TReFID program complements and exceeds in its data content the Web-based phylogenetic assignment tool recently described by A. D. Kent, D. J. Smith, B. J. Benson, and E. W. Triplett (Appl. Environ. Microb. 69:6768-6766, 2003). The method to identify bacteria is different, as is the region of the 16S rRNA gene employed in the present program. For the present communication the software of the tRF profiles has also been extended to allow screening for genes coding for N2 fixation (nifH) and denitrification (nosZ) in any bacterium or environmental sample. A number of controls were performed to test the reliability of the TReFID program. Furthermore, the TReFID program has been shown to permit the analysis of the bacterial population structure of bacteria by means of their 16S rRNA, nifH, and nosZ gene content in an environmental habitat, as exemplified for a sample from a forest soil. The use of the TReFID program reveals that noncultured denitrifying and dinitrogen-fixing bacteria might play a more dominant role in soils than believed hitherto.

Bacteria↗
PubMed2005

An evaluation of two screening tools for cognitive impairment in older emergency department patients.

OBJECTIVES: Screening for cognitive impairment in older emergency department (ED) patients is recommended to ensure quality care. The Mini-Mental State Examination (MMSE) may be too long for routine ED use. Briefer alternatives include the Six-Item Screener (SIS) and the Mini-Cog. The objective of this study was to describe the test characteristics of the SIS and the Mini-Cog compared with the MMSE when administered to older ED patients. METHODS: This institutional review board-approved, prospective, randomized study was performed in a university-affiliated teaching hospital ED. Eligible patients were 65 years and older and able to communicate in English. Patients who were unable or unwilling to perform testing, who were medically unstable, or who received medications affecting their mental status were excluded. Patients were randomized to receive the SIS or the Mini-Cog by the treating emergency physician. Investigators administered the MMSE 30 minutes later. An SIS score of <or=4, the Mini-Cog's scoring algorithm, and an MMSE score of <or=23 defined cognitive impairment. RESULTS: A total of 149 of 188 approached patients were enrolled; 74 received the SIS and 75 the Mini-Cog. Fifty-five percent were female, the average age was 75 years, and 23% had an MMSE score of <or=23. The SIS had a sensitivity of 94% (95% confidence interval [CI] = 73% to 100%) and a specificity of 86% (95% CI = 74% to 94%). The Mini-Cog had a sensitivity of 75% (95% CI = 48% to 93%) and a specificity of 85% (95% CI = 73% to 93%). CONCLUSIONS: The SIS, using a cutoff of <or=4 as impaired, is a promising test for ED use. It is short, easy to administer, and unobtrusive, allowing it to be easily incorporated into the initial assessment of older ED patients.

Aged↗
PubMed2003

[Studies on the testis regression related gene profile in aged male].

OBJECTIVE: To understand the mechanism of testis regression in aging male. METHODS: Human testis tissues were obtained during related operation with informed consent (normal young male 3 cases and aged male 3 cases). Total RNA was isolated by QIAGEN RNAeasy kit. Differentiations of gene expression were studied by Clon-Tech cDNA microarray methods and the differential expression gene in aged male were classified by Venter's classify system and the candidate genes were investigated by RT-PCR analysis. RESULTS: In the results of cDNA microarray we found 117(1.46%) gene differentiations in aged male at least more than 1.0 fold. Among them, the 83 genes were down-regulated and the 34 genes up-regulated. The down expressed genes related to metabolism were 16(19.3%), gene or protein expression 18(21.7%), cell signaling or cell communication 16(19.3%), cell division 19(22.9%), cell structure or motility 6(7.2%) and unknown function 4 genes (4.8%). The up expressed genes related to cell division were 11 (32.4%), gene or protein expression 10(29.4%) and metabolism 3 (8.8%). It is interesting to find that respiratory chain related gene cox7a2 was up-regulated and atp50 down-regulated significantly which as further confirmed by RT-PCR analysis with sequence analysis in the products of the RT-PCR by T-A cloning. CONCLUSION: The gene expression profile in aged male testis was changed significantly as compared with that in normal young controls; testis regression in aging male may relate multi-gene differentiations, especially the differentiations of respiratory chain related gene cox7a2, atp50, which may be an important candidate gene in the study of the mechanism of testis regression in aging male.

Cell Differentiation↗
PubMed1992

[Embolization for traumatic carotid cavernous sinus fistula using platinum coil].

We treated a patient with a traumatic carotid-cavernous fistula (CCF) by embolization using a Tracker catheter and platinum coils by transarterial and transvenous approaches. A 65-year-old female sustained an injury in the right frontal region of the head in April, 1989. After 1 month, she was admitted to our hospital due to exophthalmos, congestion of the palpebral conjunctiva, ptosis, and a bruise in the right frontal region of the head. Right carotid angiography showed a CCF between the anterior ascending segment and the horizontal segment that drains into the superior ophthalmic vein, superior petrosal sinus and inferior petrosal sinus. To occlude the fistula, embolization was performed twice using platinum coils. In the first embolization, the cavernous sinus was approached transarterially and transvenously using a Tracker catheter system, and a total of 7 platinum coils were used for the embolization. The bruise disappeared immediately after embolization but recurred 3 days after the operation. Angiography demonstrated re-communication of the CCF. The second embolization was initially performed using a detachable balloon, but the balloon could not be passed through the fistula. Therefore, a Tracker catheter was advanced to the fistula transarterially and embolization was performed using 3 platinum coils. The fistula was occluded. Follow-up angiography after 1 year in August, 1990 showed complete occlusion of the fistula. The detachable balloon system was recently introduced in neurological and radiological departments, as a new surgical method for CCF. At present, this method is the first choice for CCF. However, the detachable balloon system presents some technical problems.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

The role of gap junctional communication in contractile oscillations in arteries from normotensive and hypertensive rats.

OBJECTIVES: To test the hypotheses that vascular supersensitivity correlates with the appearance of contractile oscillations; vascular oscillations are mediated by gap junctions; and gap junctional communication is altered in the vasculature in stroke-prone spontaneously hypertensive (SHRSP) compared with Wistar-Kyoto (WKY) rats. DESIGN AND METHODS: Helical strips of mesenteric and tail arteries from SHRSP and WKY rats were mounted in tissue baths for measurement of isometric force. Cultures of mesenteric arterial cells were used for measurement of Lucifer yellow dye transfer and abundance of connexin43 mRNA, a monomer of gap junctions. RESULTS: Mesenteric arteries from SHRSP that displayed spontaneous oscillations were more sensitive to the contractile agonist 5-hydroxytryptamine than those from SHRSP and WKY rats that displayed no oscillations. In addition, SHRSP tail arteries displayed norepinephrine-induced oscillations. The putative gap junction up-regulator tetraethylammonium (10(-3)-10(-1) mol/l) induced oscillations (1-5 cycle/min) in arteries from both rat strains. These oscillations were not altered by endothelium removal or phentolamine and were blocked by heptanol (10(-3) mol/l). Although tetraethylammonium and heptanol caused similar effects in both arteries, heptanol-sensitive agonist-induced oscillations persisted only in the tail artery of SHRSP. Tetraethylammonium increased dye transfer between contiguous cells approximately 35% above basal levels both for SHRSP and WKY cells. In both cell lines, heptanol reduced basal- and tetraethylammonium-stimulated dye transfer. Total RNA from WKY rat and SHRSP cultured cells hybridized strongly and to a similar magnitude with a complementary DNA probe for messenger RNA for connexin43. CONCLUSIONS: Gap junctional communication is important in vascular reactivity and might play a part in the development of oscillations. Altered gap junctional communication could not be demonstrated in cell cultures nor in some contractile experiments. It is possible that the culture conditions failed to mimic conditions in vivo that differentially regulate gap junctions in the hypertensive state, but it is also possible that gap junctional activity is not abnormal in hypertension.

Alcohols↗
PubMed2005

Endovascular stent graft treatment of a traumatic aortocaval fistula.

Aortocaval fistula (ACF) is an infrequently reported sequela of trauma. Most ACF have been repaired via an open approach. During the past 10 years, there has been one reported case of spontaneous ACF and two cases of traumatic ACF repaired using an endovascular technique. We present a third case of traumatic ACF repaired with an endovascular stent graft. A 40-year-old male sustained two gunshot wounds to the right chest and one to the right upper abdomen. He was taken from the emergency department directly to the operating room, where an exploratory laparotomy was performed. Through-and-through injuries to the stomach and transverse colon were repaired primarily. Subsequently, the patient developed abdominal compartment syndrome. An urgent exploratory laparotomy was performed, revealing a nonbleeding hematoma on the posterior lateral surface of the right lobe of the liver, which was left undisturbed. Open abdominal management was instituted with vacuum pack closure. On the nineteenth hospital day, the patient again had a significant decrease in hematocrit. An aortogram was performed in order to evaluate the patient for intrahepatic arterial bleeding amenable to transcatheter embolization. There was no evidence of hepatic arterial bleeding. However, a supraceliac ACF was identified. The patient was taken to the operating room, and an AneuRx aortic extension cuff was advanced under fluoroscopy and deployed to cover the fistula. Completion angiography revealed total obliteration of the ACF and appropriate placement of the stent graft. Postoperatively, the patient was returned to the intensive care unit, where his hospital course was complicated by ventilator-associated pneumonia and sepsis. Repeat computed tomographic scanning 6 months and 1 year following this repair demonstrated patency of the graft without evidence of graft migration or aortocaval communication. Further research and experience are necessary with this technique regarding long-term outcome and technical aspects. In particular, the sizing problems associated with repair of acute traumatic ACF in emergency situations should be addressed. The endovascular approach provides an attractive and exciting alternative to traditional methods for repair of ACF.

Adult↗