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Attitudes of veterinary students at one US college toward factors relating to farm animal welfare.

RATIONALE FOR STUDY: The American Veterinary Medical Association's policy states that veterinarians are obliged to promote good animal welfare. In order to establish how compatible the attitudes of future veterinarians in one North American Veterinary College were with the promotion of good animal welfare, students were surveyed with respect to their opinions about the humaneness of commonly employed agricultural procedures (e.g., hot branding) and their beliefs about the cognitive ability of various domesticated species. METHODOLOGY: A Web-based questionnaire was made available to all veterinary students at Cornell University. Descriptive summary data were collected with regards to students' perceptions of the cognitive abilities of six different domesticated species. Students were also asked if they considered certain agricultural procedures to be humane for each of these species. The data were analyzed with respect to students' future career goals. Chi-squared tests and nonparametric statistical techniques were used to examine differences between species and desired career goals. RESULTS AND CONCLUSIONS: Veterinary students were more likely to believe that dogs and cats had cognitive abilities than farm animals did. Students considered various procedures to be more humane for farm mammals than for dogs and cats. Students aspiring to work with food animals considered more procedures to be humane for all species than did students aspiring to work with small animals. The inconsistency of students' attitudes for different species has implications for veterinary education and animal welfare. Scientific fields integral to understanding animal welfare may need to be emphasized within the veterinary educational curriculum.

Animal Husbandry↗

Effects of alley and stall surfaces on indices of claw and leg health in dairy cattle housed in a free-stall barn.

A 15-wk 2 x 3 factorial trial in a university dairy herd compared the effects of two alley surfaces and three free-stall beds on indices of lameness. Alley surfaces were grooved concrete (Ct) or 1.9-cm-thick interlocking rubber mats (R). Stalls were deep sand (S), rubber mattresses (M), or concrete (C). Mattress and concrete stalls were bedded with sawdust. At wk 1 and 15, the hind claws and hocks of 120 primi- (n = 69) and multiparous (n = 51) cows were scored for lesions and three claw measurements (dorsal wall length, heel depth, and toe angle) were recorded. Rates of lateral and medial claw growth and wear were calculated by measuring the migration of a reference mark away from the coronet. Digital photographs of claw surfaces were used to rescore claw lesions. Clinical lameness was evaluated by assigning a locomotion score from 1 to 4 to each cow during wk 1, 5, 10, and 14. Digital dermatitis (present/not present) and interdigital dermatitis (mild, moderate, or severe) were recorded at wk 15. The number of days that cows spent in a hospital barn was recorded. Before assignment, cows were professionally foot trimmed, sorted by initial claw lesion score, and then randomized in consecutive blocks of three to stall treatments. Photograph scores were highly repeatable. Nonparametric statistical techniques were used for analyses of rank data. Claw lesion score increased significantly for all treatment groups except RC and RS; however, when early lactation cows were excluded, no differences were found between treatment groups. Hock scores increased significantly more for cows in CtC than in CtS or RS. Significantly more animals from RC spent more than 10 d in the hospital pen compared with RM and RS. Groups did not significantly differ for clinical lameness. Cows in RS and RC had significantly lower rates for lateral claw net growth than those in CtM. Having moderate or severe interdigital dermatitis at wk 15 was associated with greater increases in claw lesion score and more treatments for digital dermatitis. All claw measurements were correlated; however, toe angle was most strongly correlated with the other two. In this experiment, stall and alley configurations did not lead to significant differences in several indices of lameness.

Animal Husbandry↗

Selection of tests for monitoring the bacteriological quality of refrigerated raw milk supplies.

Raw milk samples were collected from 10 producer bulk tanks. Samples were then subdivided so that milks were subsequently stored at 1.7, 4.4, 7.2, and 10.0 degrees C for 24 and 48 h. After storage, samples were analyzed by seven plating methods: standard plate count, psychrotrophic bacterial count, rapid psychrotrophic count, preliminary incubation count, mesophilic plate count, laboratory pasteurized count, and coliform count by violet red bile agar technique. Impedance protocols on a Bactometer Model 123 for total count, psychrotrophic count, mesophilic count, and coliform count were also used to evaluate the bacteriological quality of the milks. Bacterial counts and impedance detection times were analyzed using nonparametric statistics. Impedance protocols for total count and psychrotrophic count were the best indicators of bacteriological quality. Preliminary incubation count was the best of the plating methods. The laboratory pasteurized count performed poorly. Impedance measurements provided information in the shortest time.

Animals↗

Optimal location of thalamotomy lesions for tremor associated with Parkinson disease: a probabilistic analysis based on postoperative magnetic resonance imaging and an integrated digital atlas.

OBJECT: Renewed interest in stereotactic neurosurgery for movement disorders has led to numerous reports of clinical outcomes associated with different treatment strategies. Nevertheless, there is a paucity of autopsy and imaging data that can be used to describe the optimal size and location of lesions or the location of implantable stimulators. In this study the authors correlated the clinical efficacy of stereotactic thalamotomy for tremor with precise anatomical localization by using postoperative magnetic resonance (MR) imaging and an integrated deformable digital atlas of subcortical structures. METHODS: Thirty-one lesions were created by stereotactic thalamotomy in 25 patients with tremor-dominant Parkinson disease. Lesion volume and configuration were evaluated by reviewing early postoperative MR images and were correlated with excellent, good, or fair tremor outcome categories. To allow valid comparisons of configurations of lesions with respect to cytoarchitectonic thalamic boundaries, the MR image obtained in each patient was nonlinearly deformed into a standardized MR imaging space, which included an integrated atlas of the basal ganglia and thalamus. The volume and precise location of lesions associated with different clinical outcomes were compared using nonparametric statistical methods. Probabilistic maps of lesions in each tremor outcome category were generated and compared. Statistically significant differences in lesion location between excellent and good. and excellent and fair outcome categories were demonstrated. On average, lesions associated with excellent outcomes involved thalamic areas located more posteriorly than sites affected by lesions in the other two outcome groups. Subtraction analysis revealed that lesions correlated with excellent outcomes necessarily involved the interface of the nucleus ventralis intermedius (Vim; also known as the ventral lateral posterior nucleus [VLp]) and the nucleus ventrocaudalis (Vc; also known as the ventral posterior [VP] nucleus). Differences in lesion volume among outcome groups did not achieve statistical significance. CONCLUSIONS: Anatomical evaluation of lesions within a standardized MR image-atlas integrated reference space is a useful method for determining optimal lesion localization. The results of an analysis of probabilistic maps indicates that optimal relief of tremor is associated with lesions involving the Vim (VLp) and the anterior Vc (VP).

Aged↗

Intraoperative femoral fractures associated with cementless total hip arthroplasty.

Between 1982 and 1986, 56 femoral fractures associated with cementless total hip arthroplasty (THA) were evaluated and compared to a randomly selected cementless THA control group without fractures. Depending upon the femoral shaft location, these fractures were classified as Types I, II or III. There were 45 (80%) Type I, 9 (16%) Type II, and 2 (4%) Type III fractures. Patient evaluations were quantified using a modified d'Aubigne-Harris scoring system. Nonparametric statistical methodology was used for fracture and control group comparisons. Treatment protocols were divided into various modalities, depending upon fracture classification. Type I and Type II fractures have no long-term prognostic hazards associated with them (P greater than 0.1), while Type III fractures appear to have analogous clinical results (sample size was too small for statistical analysis).

Adult↗

Comparison of electrophysiologic monitors with clinical assessment of level of sedation.

OBJECTIVE: To assess the correlation between 2 clinical sedation scales and 2 electroencephalographic (EEG)-based monitors used during surgical procedures that required mild to moderate sedation. PATIENTS AND METHODS: Patients scheduled for elective surgery participated in this Institutional review board-approved study from March 2003 to February 2004. Level of sedation was determined both clinically using the Ramsay and the Observer's Assessment of Alertness/Sedation scales and with 2 EEG measures (the Bispectral Index version XP [BIS XP] or the Patient State Analyzer [PSA 4000]). Correlation between these 2 measures of sedation were tested using nonparametric statistical tests. RESULTS: The BIS XP monitor was used in 26 patients, and the PSA 4000 monitor was used in 24 patients. The Ramsay and Observer's Assessment of Alertness/Sedation scores correlated with each other (r = -0.96; P < .001) and with both the BIS XP (r = -0.89 and r = 0.91, respectively; P < .001) and the PSA 4000 (r = -0.80 and r = 0.80, respectively; P < .001) values. However, this correlation was strongest only at the extremes. Between the BIS XP and PSA 4000 values of 61 and 80, the clinical sedation scores varied greatly. CONCLUSION: On the basis of our results, these EEG-based monitors cannot reliably distinguish between light and deep sedation.

Computer Terminals↗

Relationship between visual-motor integration and handwriting skills of children in kindergarten: a modified replication study.

OBJECTIVE: The purpose of this study was to examine the relationship of performance on the Developmental Test of Visual-Motor Integration (VMI; Beery, 1997) to handwriting legibility in children attending kindergarten. The relationship of using lined versus unlined paper on letter legibility, based on a modified version of the Scale of Children's Readiness in PrinTing (Modified SCRIPT; Weil & Cunningham Amundson, 1994) was also investigated. METHOD: Fifty-four typically developing kindergarten students were administered the VMI; 30 students completed the Modified SCRIPT with unlined paper, 24 students completed the Modified SCRIPT with lined paper. Students were assessed in the first quarter of the kindergarten school year and scores were analyzed using correlational and nonparametric statistical measures. RESULTS: Strong positive relationships were found between VMI assessment scores and student's ability to legibly copy letterforms. Students who could copy the first nine forms on the VMI performed significantly better than students who could not correctly copy the first nine VMI forms on both versions of the Modified SCRIPT. CONCLUSION: Visual-motor integration skills were shown to be related to the ability to copy letters legibly. These findings support the research of Weil and Cunningham Amundson. Findings from this study also support the conclusion that there is no significant difference in letter writing legibility between students who use paper with or without lines.

Child Development↗

Plasma chemistry reference values in ostriches.

Reference values for 18 plasma chemical variables in blue neck ostriches (Struthio camelus australis, n = 60, age 24-36 mo) were established for use in veterinary clinical practice using nonparametric statistics. The following values were established for the percentiles P2.5 and P97.5: sodium 147-157 mmol/L, calcium 2.4-4.8 mmol/L, inorganic phosphate 1.3-2.3 mmol/L, chloride 94-105 mmol/L, glucose 10.3-13.7 mmol/L, urea 0.5-0.8 mmol/L, uric acid 351-649 mumol/L, bile acids 8-33 mumol/L, total protein 39-56 g/L, albumin-globulin ratio 0.45-0.59, osmolality 304-330 mOsm/kg, alkaline phosphate 69-217 IU/L, aspartate aminotransferase 243-418 IU/L, gamma-glutamyltransferase 0-1 IU/L, creatine kinase 1648-4894 IU/L, glutamate dehydrogenase 8-17 IU/L, and lactate dehydrogenase 860-2236 IU/L. The plasma calcium concentration was significantly (P < 0.001; r = 0.74) related to the total protein concentration and an adjustment-formula for calcium was derived: adjusted Ca (mmol/L) = Ca (mmol/L)--0.09 TP (g/L) + 4.4. The influence of blood sample treatment on the plasma potassium concentration as seen in other avian species was demonstrated in a separate experiment, emphasizing the need to separate plasma and cells immediately after collection in avian blood samples.

Animals↗

Analysis of the change in work patterns following installation of an inpatient pharmacy computer system.

An experiment was designed to determine if the installation of a pharmacy computer produced a significant change in the distribution of routine inpatient dispensing activities for pharmacy personnel. Data were obtained using time lapse motion picture photography and work sampling procedures. Cameras were placed in three different locations for 6 days over a 2-week period before and after installation of the computer. A sample of approximately 2000 observations was reduced to machine readable format and analyzed using nonparametric statistical procedures. Results indicated a shift in work patterns of pharmacy personnel. It was concluded that the installation of a pharmacy computer had a significant effect on the distribution of routine inpatient dispensing activities. Pharmacy management should consider this information in anticipating efficient use of personnel and proper placement of computer hardware.

Computers↗

[The prevention of risk due to the manual lifting of patients: the psychosocial component].

A high percentage of musculoskeletal disorders in nursing staff with the task of patient lifting is reported in the literature. These disorders are considered to be of multiple etiology and attempts have been made not only to assess the physical load but also to identify the direct or indirect influence of organisational and psychosocial factors so that preventive measures be more appropriate and effective (Law 626/94). In this context, in a recent publication NIOSH recalled that psychosocial factors can alter the relationship between exposure to physical loads and the development or the prognosis of these disorders, and stresses that understanding these relationships is the crucial factor in assessment of exposure that can be addressed with preventive and therapeutic measures. A study was carried out on the staff (113 subjects) of a large hospital in northern Italy with departments recognised by certified occupational physicians as at risk for the musculoskeletal apparatus. In order to quantify the working conditions and the disorders of the spine, a protocol proposed by the Ergonomics of Posture and Movement Research Unit of Milan University was further developed and validated. For assessment of psychosocial factors an Italian version of R. A. Karasek's "Job Content Questionnaire" was drawn up and validated by the Centre for Study and Research of Chronic Degenerative Diseases in Working Environments of Milan University. In addition, Borg's Scale was used for perception of physical load, Kurimori and Kakizaki's Scale for mental fatigue, Kjellberg and Iwanowski's Scale for states of stress, plus the Maslach burnout inventory. Nonparametric statistical analysis was applied to determine the influence of physical and organisational and psychosocial factors on disorders of the musculoskeletal apparatus. The results confirm a good agreement between the objective and subjective assessments of "manual patient handling" risk (Kendall p from 0.26 to 0.37, p > 0.001) and the significant relationships between psychosocial factors and disorders of the lumbar region of the spine: past history of episodes of acute low back pain is associated with limited possibility of making independent decisions (U-Mann Whitney z = 2.81, p 0.004) and job insecurity (U-Mann Whitney z = -2.36, p 0.01); episodes of acute low back pain above the threshold in the previous year were associated with low discretionary powers at work. The results will be discussed on the basis of the possible prevention measures.

Adult↗

Insomnia in primary care patients.

STUDY OBJECTIVES: To determine the prevalence and characteristics of insomnia in primary care patients, to examine patients' help-seeking behavior, and to compare the frequency of insomnia in primary care patients to the general population. METHODS: 286 patients from primary care clinics in San Diego, California (n = 96), and in Haleiwa and Honolulu, Hawaii (n = 190) participated. Sleep study questionnaires were distributed by front desk receptionists to all patients over 18 years of age upon arrival at the clinic for an appointment with the physician. Completed questionnaires were collected at the clinic or returned by mail. Comparisons were made by using nonparametric statistics. A logistic regression analysis using backward elimination was done to develop a model showing predictors of who would consult with the physician about a sleep problem. RESULTS: The prevalence of insomnia in primary care patients was 69%, with 50% reporting occasional insomnia and 19% reporting chronic insomnia. As expected, patients with chronic insomnia had the most severe sleep complaints as well as the poorest daytime functioning, and exhibited the most help-seeking behaviors. The four predictors of discussing insomnia with a physician were how patients felt physically, number of years of insomnia, age, and income. CONCLUSIONS: The primary care population has a higher prevalence of insomnia than the general population, probably because of concomitant psychiatric and medical illnesses. Although many of the characteristics of the sleep complaints are easily detected, most patients with insomnia are not treated effectively.

Adolescent↗

[Idiopathic partial epilepsy with occipital paroxysms].

BACKGROUND: The syndrome of idiopathic partial epilepsy with occipital paroxysms in the electroencephalogram (EEG) shows a considerable clinical and prognostic heterogeneity. The semiology of seizures varies considerably among patients and its hallmark, occipital paroxysms blocked by eye opening, may appear in other idiopathic or symptomatic epilepsies of childhood and even in nonepileptic disorders, notably basilar artery migraine. To address these unresolved issues in children with this rare form of epilepsy, the present paper utilized a longitudinal approach and investigated the significance of electrophysiologic and clinical characteristics necessary for the diagnostic and prognostic evaluation during a long-term follow-up. PATIENTS AND METHODS: Over a 9-year period all patients, aged 1-15 years, who showed occipital paroxysms in EEG recordings were included in this study. In addition, clinical correlates were available for all these patients. Neurological, psychiatric and other clinical examinations were done in all patients. Whenever indicated, the neuroimaging of the brain (computerized tomography and/or magnetic resonance) was performed to establish the symptomatic aetiology. The epileptic syndromes were determined according to criteria of the International classification. A detailed EEG analysis of all patients, performed during a 3-12 year follow-up period, included hyperventilation, photic stimulation and a thorough testing of visual reactivity with exclusion of central vision. The incidence of EEG characteristics in patients with various epileptic syndromes was compared and its significance for the differential diagnosis was tested by nonparametric statistical methods. The clinical semiology of epilepsy and/or other associated disorders and EEG findings were compared among the patients with idiopathic partial epilepsy and occipital paroxysms. RESULTS: Occipital epileptiform paroxysms were recorded in EEGs of 76 children with various clinical diagnoses but only 58 patients had seizures. The incidence of epilepsy (39 patients or 51%) was slightly higher than that of various non-epileptic disorders (37 patients or 49%). Two types of these paroxysms were analyzed: reactive (appearing at exclusion of central vision and disappearing on eye opening) or unreactive (persisting in the above situations). The difference in incidence of seizures (in a total of 58 patients) depending on the types of paroxysms was not statistically significant. EEG characteristics in 25 patients with both reactive paroxysms and seizures were compared in relation to the aetiology of epileptic syndromes. Comparing EEG in various types of epilepsy with reactive paroxysms, the statistical analysis (using Fischer's exact test) established that slowed background activity was significantly more frequent in symptomatic partial epilepsy than in idiopathic syndromes. On the other hand, EEG normalization during the follow-up period was a rule in benign epilepsy with centro-temporal paroxysms and in childhood absence epilepsy, and it was significantly more frequent in idiopathic partial epilepsy with occipital paroxysms than in symptomatic partial epilepsy. However, EEG findings per se cound not differentiate idiopathic partial epilepsy with occipital paroxysms from other epileptic syndromes. Neither seizures semiology could distinguish between different forms of occipital lobe epilepsy. Therefore, a correct syndromic and aetiologic classification for each patient with occipital spike-wave paroxysms required the combined and thorough assessment integrating clinical examination, clinical neurophysiological analyses, and neuroimaging studies during the follow-up. Using all above methods during the follow-up of 11 patients with idiopathic partial epilepsy with occipital paroxysms (IPEOP) it was found that this syndrome had often a very favorable prognosis if characterized by rare, nocturnal seizures beginning in preschool age. (ABSTRACT TRUNCATED)

Adolescent↗

A replication study of obsessional followers and offenders with mental disorders.

The purpose of this study was to compare certain demographic, clinical, and criminal variables within subgroups of obsessional followers, and compare them to a group of offenders with mental disorders to attempt to replicate earlier findings. A static group archival design utilized a non-random group of convenience and a randomly selected comparison group. Sixty-five obsessional followers and 65 offenders with mental disorders were evaluated by psychiatrists and psychologists for court ordered reasons during their criminal proceedings. Both groups were evaluated during the same period, in the same court diagnostic clinic, and generally for sentencing determinations. The obsessional followers were measured on demographic, diagnostic, pursuit, victim, threat, violence, emotional, motivational, and defense variables. Inferential comparisons that used parametric and nonparametric statistics were done within and between groups on select variables. The obsessional followers had significantly greater estimated IQ than the offenders with mental disorders, but were neither older nor better educated. There were no significant differences in the high prevalence of both DSM-IV Axis I and II diagnoses. Obsessional followers who stalked prior sexual intimates were significantly more likely to have a substance abuse or dependence diagnosis. Obsessional followers who stalked strangers or acquaintances were more likely to be delusional. The majority of the obsessional followers, primarily motivated by anger, both threatened and were violent toward person or property. The modal obsessional follower is an average or above IQ, unemployed, unmarried male in his fourth decade of life. chronically pursuing a prior sexually intimate female. He is diagnosed with substance abuse or dependence and a personality disorder NOS, and has a prior psychiatric, criminal and substance abuse history. He is angry, likely to threaten her, and assault her person or property without causing serious injury.

Cohort Studies↗

[Proposal and preliminary validation of a check-list for the assessment of occupational exposure to repetitive movements of the upper lims].

Over the last few years the Authors developed and implemented, a specific check-list for a "rapid" assessment of occupational exposure to repetitive movements and exertion of the upper limbs, after verifying the lack of such a tool which also had to be coherent with the latest data in the specialized literature. The check-list model and the relevant application procedures are presented and discussed. The check-list was applied by trained factory technicians in 46 different working tasks where the OCRA method previously proposed by the Authors was also applied by independent observers. Since 46 pairs of observation data were available (OCRA index and check-list score) it was possible to verify, via parametric and nonparametric statistical tests, the level of association between the two variables and to find the best simple regression function (exponential in this case) of the OCRA index from the check-list score. By means of this function, which was highly significant (R2 = 0.98, p < 0.0000), the values of the check-list score which better corresponded to the critical values (for exposure assessment) of the OCRA index looked for. The following correspondance values between OCRA Index and check-list were then established with a view to classifying exposure levels. The check-list "critical" scores were established considering the need for obtaining, in borderline cases, a potential effect of overestimation of the exposure level. On the basis of practical application experience and the preliminary validation results, recommendations are made and the caution needed in the use of the check-list is suggested.

Arm↗

Spinal metastases from renal cell carcinoma: effect of preoperative particle embolization on intraoperative blood loss.

BACKGROUND AND PURPOSE: Surgical repair of spinal metastases from renal origin is often complicated by excessive bleeding. The purpose of this study was to assess the effect of preoperative particulate embolization on intraoperative blood loss. METHODS: Twenty spinal metastases from renal origin (17 patients) treated by preoperative embolization with polyvinyl alcohol particles were analyzed retrospectively. Surgical decompression was performed within 2 days after embolization. A control group of 10 patients with 11 spinal metastases of renal origin underwent surgery without embolization. The effect of preoperative embolization, of completeness of embolization, and of particle size on the estimated intraoperative blood loss was analyzed using nonparametric statistical tests. RESULTS: Complete embolization was achieved in 10 cases and partial embolization in the other 10. The estimated blood loss of 19 embolized and 11 control cases was available from the surgical report. Median intraoperative blood loss in 19 embolized lesions was 1500 mL (range, 300-8000 mL), compared with 5000 mL (range, 1440-15000 mL) in the control group. Even after partial embolization, blood loss (median, 2000 mL) was significantly lower than in the control group. No significant differences in estimated blood loss were noted between the use of particles smaller than 250 microm and those larger than 250 microm. No embolization-related permanent neurologic deficit or skin or muscle necrosis occurred. CONCLUSION: Preoperative embolization of spinal metastases of renal origin with polyvinyl alcohol particles is safe and might reduce intraoperative blood loss significantly. Even partial embolization seems to be effective.

Aged↗

Human papillomavirus infection and epidermal growth factor receptor expression in primary laryngeal squamous cell carcinoma.

PURPOSE: This study was designed to add new data about laryngeal carcinogenesis, a multistep process in which chemical and/or viral agents induce and promote successive alterations in growth factor-linked signal transmission pathways, genetic instability, and mutations in key genes involved in cell growth control. Epidemiological evidence suggests that human papillomavirus (HPV) infection may be associated with the development of laryngeal cancer. EXPERIMENTAL DESIGN: In this report, we have analyzed the prevalence of HPV infection and epidermal growth factor receptor (EGFR) expression in a series of 42 laryngeal squamous cell carcinomas by PCR with HPV consensus primers and by a radioligand receptor assay, respectively. RESULTS: HPV DNA was detected in 15 of 42 (35.7%) tumors, and it belonged almost exclusively to the highly oncogenic HPV-16, HPV-18, and HPV-33 genotypes. At analysis by Mann-Whitney nonparametric statistical test, EGFR level was found to be significantly higher in HPV-infected than in HPV-negative cases (T = 440; P = 0.002). EGFR overexpression (EGFR-positive status >6 fmol/mg protein, the arbitrary cutoff value chosen) was found in 20 of 42 (47.6%) tumors, and it was associated with HPV infection in a statistically significant extent (chi(2) = 4.686; P = 0.03). CONCLUSIONS: Viral oncoproteins have been shown to induce a perturbation of the cell response to signals for growth and differentiation; these findings confirm that enhanced EGFR expression and activation in laryngeal squamous cell carcinoma may occur also as a consequence of HPV infection and support the hypothesis of an involvement of HPV infection in laryngeal carcinogenesis.

Carcinoma, Squamous Cell↗

Effect of air abrasion and resin composite on microleakage of Class V restorations bonded with self-etching primers.

PURPOSE: The purpose of this in vitro study was to determine the effect of air-abrasion pretreatment on microleakage of Class V resin composite restorations bonded with self-etching primers. MATERIALS AND METHODS: A total of 54 Class V cavities prepared either with diamond burs or air abrasion (KCP 1000) was restored with resin composites using adhesive systems with self-etching priming agents (Clearfil Liner Bond 2 or Resulcin AquaPrime + Monobond) and thermocycled 2,500 times. The degree of dye penetration (0.5% methylene blue solution) was scored on an ordinal scale at 25X magnification on longitudinally cut sections of the specimens. Wall adaptation at the tooth-restoration interfaces was evaluated under a SEM using replicas of the sectioned teeth. RESULTS: Severe microleakage occurred at the gingival dentinal margins, and less microleakage was detected at the enamel cavity margins. Nonparametrical statistical analysis (H-test) demonstrated no significant differences in microleakage among the different groups. Comparison of dye penetration data and SEM findings showed that with both self-etching priming agents, microleakage occurred in the absence of gaps. CONCLUSION: Use of air abrasion in combination with self-etching priming agents cannot prevent microleakage at the dentin-resin interface of Class V resin composite restorations.

Air Abrasion, Dental↗

Germ-line p53-targeted disruption inhibits helicobacter-induced premalignant lesions and invasive gastric carcinoma through down-regulation of Th1 proinflammatory responses.

p53 is a tumor suppressor gene that is mutated in many human malignancies, including gastric cancer. It remains unclear why patients with germ-line p53 mutations (i.e., Li-Fraumeni syndrome) are not at increased risk for gastric adenocarcinoma, despite the fact that they show a high rate of many other tumors. Furthermore, the precise relationship between germ-line p53 mutations and the response to chronic bacterial infections (such as Helicobacter spp.) has not been investigated. To assess the role of germ-line p53 deletions in modulating the progression to gastric cancer, p53(+/-) and wild-type (WT) C57BL/6 mice were infected with H. felis. The gastric pathology and immune response in these two groups of mice were analyzed for up to 15 months postinfection. The gastric fundus and antrum were evaluated independently using a 0-4 scale to score inflammation, parietal and chief cell loss, mucus metaplasia, and helicobacter colonization. Nonparametric statistical analysis was performed to determine the effects of p53(+/-), infection status, and postinoculation (p.i.) time on inflammation, preneoplastic changes, invasive lesions, and helicobacter colonization. mRNA expression for gammaIFN, interleukin (IL)-1, IL-10, and IL-4 was quantified by PCR. Sera were also evaluated for H. felis antibody by ELISA. Antral inflammation increased significantly with time in infected mice. There was a significant, protective effect on the development of preneoplastic fundic lesions and invasive carcinoma attributable to the deletion of one p53 allele (P < 0.05). Submucosal invasive foci were observed in 9 of 11 WT-infected mice ranging from 13 to 15 months p.i.; invasion of adjacent submucosal blood vessels by glandular epithelia also was present in 5 of these mice. None of these lesions were observed in 33 p53(+/-) mice, infected or not, at any time p.i. p53(+/-) mice had significantly higher helicobacter colonization consistent with a Th2 host response. In sera from WT mice, IgG2a, considered a proinflammatory Th1 response, continued to rise throughout the 15-month study (P < 0.004). In contrast, IgG2a levels of the p53(+/-) mice were 50-60% lower than those of the WT mice at each time point (P range, <0.012 to 0.002) and did not progress in magnitude between 12 and 15 months of chronic H. felis infection (P = 0.167). mRNA levels for gammaIFN and IL-1 were significantly up-regulated in WT mice infected with H. felis (P < 0.05) but were slightly elevated or were at background levels in p53(+/-) mice. IL-10 and IL-4 mRNA expression was not significantly different from control samples. Our results support the hypothesis that germ-line deletion of one p53 allele results in a down-regulated Th1 response to gastric helicobacter infection, possibly because of T-cell senescence, which may indirectly protect against the development of gastric cancer and other epithelial-derived neoplasms associated with chronic inflammation.

Animals↗