The effect of spiked boots on logger safety, productivity and workload

Analysis of 1657 lost-time logging accidents in the New Zealand logging industry (1985-1991) indicates that 17.5% were as a result of slips, trips and falls and a total of 2870 days were lost. Most (56%) of these slipping, tripping and falling accidents occurred in the felling and delimbing phase of the logging operation, where 37% of the workforce are employed. In an attempt to reduce the number of slipping injuries to loggers employed in felling and delimbing, a study of the effectiveness of spike-soled (caulk) boots was undertaken. Four loggers were intensively observed at work, by continuous time-study methods, while wearing their conventional rubber-soled boots and then spike-soled boots. The number of slips, work methods used, physiological workload and productivity were compared for loggers wearing the two footwear types. Results indicated that spike-soled boots were associated with a significant reduction in the frequency of slips and had no adverse effect on work methods, physiological workload or productivity. Spike-soled boots are now being promoted for use by loggers in New Zealand as a simple method to reduce slipping, tripping and falling accidents.

Deadenylation of the unstable mRNA encoded by the yeast MFA2 gene leads to decapping followed by 5'-->3' digestion of the transcript

The first step in the decay of some eukaryotic mRNAs is the shortening of the poly(A) tail. To examine how the transcript body was degraded after deadenylation, we followed the decay of a pulse of newly synthesized MFA2 transcripts while utilizing two strategies to trap intermediates in the degradation pathway. First, we inserted strong RNA secondary structures, which can slow exonucleolytic digestion and thereby trap decay intermediates, into the MFA2 5' UTR. Following deadenylation, fragments of the MFA2 mRNA trimmed from the 5' end to the site of secondary structure accumulated as full-length mRNA levels decreased. In addition, in cells deleted for the XRN1 gene, which encodes a major 5' to 3' exonuclease in yeast, the MFA2 transcript is deadenylated normally but persists as a full-length mRNA lacking the 5' cap structure. These results define a mRNA decay pathway in which deadenylation leads to decapping of the mRNA followed by 5'-->3' exonucleolytic degradation of the transcript body. Because the poly(A) tail and the cap structure are found on essentially all mRNAs, this pathway could be a general mechanism for the decay of many eukaryotic transcripts.

Application of stereotactic radiosurgery to the head and neck region

Nasopharyngeal carcinoma recurrent following primary radiation therapy has been treated with surgery and reirradiation. Reirradiation is often limited by the tolerance of structures previously treated. Radiosurgery was used to boost the recurrent site while avoiding critical structures. Seven patients were evaluated for treatment. Three patients met requirements for treatment. The lesions invaded the parapharyngeal region, the base of skull, cavernous sinus, cranial nerves, or carotid artery. Treatment included a radiosurgery boost utilizing multiple isocenters, noncoplanar arcs, and arc weighting, to yield a plan conforming to the tumors while avoiding critical anatomical structures. The patients tolerated the procedure well with minor acute side effects. Follow-up included magnetic resonance imaging (MRI) and positron emission tomography (PET). Two lesions responded, and one had no significant change. One patient had a regional recurrence. Two patients had distance recurrence. Long term side effects include trismus, parotiditis, ear fullness, hemorrhage, and pain. Radiosurgery may improve the local control rate of such lesions, however, with the severe long term complications of single fraction radiosurgery in the head and neck region this procedure may be more beneficial if the treatment is fractionated.

Positron emission tomography with fluorodeoxyglucose to evaluate tumor response and control after radiation therapy

PURPOSE

Following radiation therapy, evaluation of viable tumor can often be difficult with anatomic imaging criteria (tumor size alone). In this study, the utility of biochemical imaging with the glucose analog 2-[F-18]fluoro-2-deoxy-D-glucose and positron emission tomography was investigated in patients treated with radiation therapy.

METHODS AND MATERIALS

Between 1990 and 1992, 19 patients were studied, including 15 patients with head and neck cancer, (4 oropharynx, 4 sinus, 3 larynx, 2 hypopharynx, 2 oral cavity [one patient], 1 nasopharynx), and 4 patients with breast cancer. Post-radiation positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose studies were done in all patients, with 9 head and neck patients receiving pre-radiation positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose scans as well. Results were correlated with other imaging techniques and pathology.

RESULTS

Positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose detected head and neck primary tumors and lymph node metastases in all nine pre-radiation scans, while magnetic resonance imaging failed to detect two primary tumors. Serial positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose showed a significant decrease in tumor activity after radiation therapy, compared to pre-radiation levels, (p < 0.05), except for two patients with increased uptake at the primary site. Biopsies of these two patients showed persistent/recurrent disease after radiation therapy, which was not detected by magnetic resonance imaging. Six additional head and neck patients, with suspicious examination and inconclusive magnetic resonance imaging, were imaged with positron emission tomography after radiation therapy only. Five patients had increased positron emission tomography activity, with corresponding biopsies positive in four patients, and negative in one patient with clinically worsening symptoms. The remaining sixth patient had minimal and stable positron emission tomography uptake, and is improving clinically. Four patients had mammogram findings suspicious for recurrence after conservation treatment for breast cancer. Positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose showed no focal activity in the breast in two patients, and increased activity in the area suspicious for recurrence in the other two patients. Biopsies correlated with positron emission tomography results.

CONCLUSION

Changes and presence of positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose activity correlated with pathologic findings in head and neck and breast cancer patients in this series. In patients with elevated or rising positron emission tomography activity after radiation therapy, persistent or recurrent disease was found in 89% of patients, (8/9). Magnetic resonance imaging did not detect the head and neck recurrences, and mammography was suspicious in patients with both benign and malignant breast changes after radiation therapy. In addition, our data indicate that in head and neck patients with pre-radiation positron emission tomography scans, a significant decrease in activity should occur after radiation therapy, if local control is to be expected.

A small segment of the MAT alpha 1 transcript promotes mRNA decay in Saccharomyces cerevisiae: a stimulatory role for rare codons

Differences in decay rates of eukaryotic transcripts can be determined by discrete sequence elements within mRNAs. Through the analysis of chimeric transcripts and internal deletions, we have identified a 65-nucleotide segment of the MAT alpha 1 mRNA coding region, termed the MAT alpha 1 instability element, that is sufficient to confer instability to a stable PGK1 reporter transcript and that accelerates turnover of the unstable MAT alpha 1 mRNA. This 65-nucleotide element is composed of two parts, one located within the 5' 33 nucleotides and the second located in the 3' 32 nucleotides. The first part, which can be functionally replaced by sequences containing rare codons, is unable to promote rapid decay by itself but can enhance the action of the 3' 32 nucleotides (positions 234 to 266 in the MAT alpha 1 mRNA) in accelerating turnover. A second portion of the MAT alpha 1 mRNA (nucleotides 265 to 290) is also sufficient to destabilize the PGK1 reporter transcript when positioned 3' of rare codons, suggesting that the 3' half of the MAT alpha 1 instability element is functionally reiterated within the MAT alpha 1 mRNA. The observation that rare codons are part of the 65-nucleotide MAT alpha 1 instability element suggests possible mechanisms through which translation and mRNA decay may be linked.

Sexual practices and attitudes of street youth in Belo Horizonte, Brazil. Street Youth Study Group

Street youth are at risk of HIV infection worldwide. To develop effective prevention strategies, information about the meanings and functions of sexual activity for street youth is needed. In this paper, data from structured questionnaires, focus group discussions, in-depth interviews and field observations are used to build up a picture of the sexual culture of 9-to-18-year-olds living and/or working on the streets of a large Brazilian city. The findings reveal that these children and adolescents engage in sexual behavior that puts them at risk of sexually transmitted diseases, including HIV/AIDS, and reinforce that sex is a multi-determined and entrenched behavior in this population. Interventions must take into account the fact that for street youth, sex is used as a means of ensuring survival, seeking comfort, finding pleasure, and dealing with psychological issues that arise during adolescence.

Inhibition of DNA repair and sensitization of cisplatin in human ovarian carcinoma cells by interleukin-1 alpha

Interleukin-1 alpha induced an increase in both the cellular accumulation of cis-diamminedichloroplatinum (II) (cisplatin) and DNA platination and significantly reduced the removal of platinum from DNA of human ovarian (NIH: OVCAR-3) carcinoma cells in culture. The combinations of IL-1 alpha and cisplatin were highly synergistic against these ovarian carcinoma cells and maximum levels of sensitization (15-20-fold) were observed during simultaneous exposure of cisplatin and IL-1 alpha. IL-1 alpha specific receptor antagonist decreased this synergy. These results strongly indicate that IL-1 alpha inhibits DNA repair, and this inhibition of DNA repair may explain, in part, a strong synergistic interaction between IL-1 alpha and cisplatin in NIH: OVCAR-3 cells.

A turnover pathway for both stable and unstable mRNAs in yeast: evidence for a requirement for deadenylation

To determine pathways of mRNA turnover in yeast, we have followed the poly(A) tail removal and degradation of a pulse of newly synthesized transcripts from four different genes. Before decay of both stable and unstable mRNAs initiated, there was a temporal lag during which the poly(A) tail was deadenylated to an oligo(A) length. Altering the deadenylation rate of an mRNA led to a corresponding change in the length of this lag. The rate of deadenylation and the stability of the oligo(A) species varied between mRNAs, explaining the differences in mRNA half-lives. To examine how the transcript body was degraded following deadenylation, we used the strategy of inserting strong RNA secondary structures, which can slow exonucleolytic digestion and thereby trap decay intermediates, into the 3' UTR of mRNAs. Fragments lacking the 5' portion of two different mRNAs accumulated after deadenylation as full-length mRNA levels decreased. Therefore, these results define an mRNA decay pathway in which deadenylation leads to either internal cleavage or decapping followed by 5'-->3' exonucleolytic degradation of the mRNA.

Detection of Trichomonas vaginalis in pregnant women with the InPouch TV culture system

Trichomonas vaginalis causes a common genitourinary infection which is frequently asymptomatic. At present, pregnant women are not usually screened for the infection unless they are symptomatic. In the present study, we screened and obtained samples for culture from all pregnant women attending a prenatal clinic with the InPouch TV culture system and compared results with those of standard culture in Diamond's medium and slide wet mount examination. The InPouch TV culture system was as reliable as Diamond's medium in detecting T. vaginalis and may be useful and effective in a pregnancy clinic setting.

Evidence for an essential non-Watson-Crick interaction between the first and last nucleotides of a nuclear pre-mRNA intron

Nuclear pre-messenger RNA splicing requires the action of five small nuclear (sn) RNAs, U1, U2, U4, U5 and U6, and more than 50 proteins. The mechanistic similarity of nuclear pre-mRNA splicing and group II self-splicing suggests that many of the central processes of nuclear pre-mRNA splicing are based on RNA-RNA interaction. To understand the mechanism of pre-mRNA splicing, the interactions, and their temporal relationships, that occur between the snRNAs and the pre-mRNA during splicing must be identified. Several snRNA-snRNA and snRNA-intron interactions have been demonstrated but the putative RNA-based interactions that recognize the AG dinucleotide at the 3' splice site during 3' cleavage and exon ligation are unknown. We report here the reciprocal suppression between 5' and 3' splice site mutations in the yeast actin intron, and propose that the 3' splice site is positioned for 3' cleavage and exon ligation, at least in part, through a non-Watson-Crick interaction between the guanosines at the 5' and 3' splice sites.

Phase I trial of dihydrolenperone in lung cancer patients: a novel compound with in vitro activity against lung cancer

Antitumor activity of the butyrophenone dihydrolenperone in non-small cell lung cancer was initially suggested by in vitro screening against tumor cells derived from fresh surgical samples using the human tumor colony-forming assay. We have completed a directed phase I trial in patients with lung cancer. Thirty-two patients with lung cancer have completed 25 courses of therapy at doses of 10 to 60 mg/square meter orally on a twice daily schedule. Twenty-three men and 9 women with a median age of 55 (range 24-69) were entered. Twenty-four were performance status 0 or 1 and 8 were 2. The maximum tolerated dose was 50 mg/square meter orally twice daily and the dose limiting toxicity was somnolence. Of the 32 patients, 18 developed symptomatic hypotension (grade 1 or 2). There was no significant hematologic, renal, or hepatic toxicity. In vitro drug testing using the MTT [3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (thiazolyl blue)] assay confirmed 50% inhibition of non-small cell and small cell lung cancer cell line growth at 70-450 micromolar concentrations. Plasma dihydrolenperone levels were at least 75-fold less than levels at which in vitro activity was observed. We conclude: 1) the maximum tolerated dose in our study is 50 mg/square meter orally twice daily, 2) the dose-limiting side effect of dihydrolenperone is somnolence, and 3) the concentrations of dihydrolenperone observed in plasma are significantly lower than those associated with in vitro activity.

Association of cervicovaginal infections with increased vaginal fluid phospholipase A2 activity

OBJECTIVE

The purpose of this study was to determine if phospholipase A2 was detectable within vaginal fluid and to correlate its presence with the presence of common lower genital tract infection or microbial conditions.

STUDY DESIGN

Pregnant women were examined at the first prenatal visit with standard clinical evaluations and microbiologic cultures or tests. Vaginal fluid samples were evaluated for phospholipase A2 activity by means of a standardized enzyme fluorometric assay. Data were stratified to control for coexisting infections.

RESULTS

Phospholipase A2 activity was detected among 29.8% of women and was independently associated with the presence of bacterial vaginosis (p < 0.001), Trichomonas. vaginalis (p < 0.04), and Chlamydia trachomatis (p < 0.02). The percentage of women with phospholipase A2 activity and the level of activity was increased in the presence of more than one infection.

CONCLUSIONS

Elevated reproductive tract phospholipase A2 concentrations among pregnant women may play roles in the pathogenesis of preterm labor and birth. Identification of pregnant women with increased concentrations in vaginal fluid may allow for development of effective intervention strategies to reduce the risk of preterm birth.

Clindamycin vaginal cream versus oral metronidazole in the treatment of bacterial vaginosis: a prospective double-blind clinical trial

Bacterial vaginosis is common among patients seen by gynecologists. Several types of therapy have been proposed. The purpose of this prospective, randomized, double-blind clinical trial was to examine the efficacy of clindamycin vaginal cream for the treatment of bacterial vaginosis. Sixty patients with symptoms of bacterial vaginosis were randomized into the study, and 46 completed the protocol. Twenty-three patients received 2% clindamycin vaginal cream (5 g applied intravaginally at bedtime for 7 days), with placebo oral tablets twice daily for 7 days. The other 23 patients received oral metronidazole tablets (500 mg twice a day for 7 days) and placebo vaginal cream (5 g intravaginally for 7 days). The cure rates for the two regimens were comparable. Twenty-two (97%) of the patients treated with clindamycin vaginal cream had improvement or cure at the first follow-up visit versus 19 (83%) of those taking metronidazole. There was no statistically significant difference between the two results. Side effects for both regimens were comparable. We conclude that 2% clindamycin vaginal cream offers similar efficacy and safety to standard oral metronidazole therapy for bacterial vaginosis.

Mutations affecting stability and deadenylation of the yeast MFA2 transcript

Decay rates of individual mRNAs in the yeast Saccharomyces cerevisiae can vary by 10- to 20-fold. To determine the basis for the rapid degradation of the mRNA encoded by the yeast MFA2 gene we have used a genetic screen to isolate mutations that increase the stability of this transcript. Analysis of point mutations obtained from this screen, and of additional lesions constructed in vitro, indicated that the MFA2 3'-untranslated region (UTR) contains sequences that specify rapid mRNA decay. Moreover, the lesions that affected mRNA decay rate also affected the process of mRNA deadenylation. Mutations in one region of the 3' UTR both decreased the rate of poly(A) shortening and increased the stability of an intermediate form in the decay pathway with an oligo(A) tail (approximately 10 nucleotides). Mutations in a second region primarily increased the stability of the oligo(A) form. These results suggest that the decay of the MFA2 mRNA initiates with the shortening of the poly(A) tail and there are specific sequences within the 3' UTR that stimulate poly(A) tail shortening as well as subsequent steps in the decay pathway. Given the similarity of this decay pathway to that seen for some mammalian mRNAs, these results suggest that mRNA deadenylation may be a common mechanism of mRNA turnover.

Depletion of protein-bound furazolidone metabolites containing the 3-amino-2-oxazolidinone side-chain from liver, kidney and muscle tissues from pigs

Ten 3-month-old pigs were treated with feed containing 300 mg furazolidone per kg for a period of 7 days, followed by withdrawal periods of 0, 1, 2, 3 or 4 weeks (two per group). The treatment resulted in the formation of protein-bound metabolites containing an intact 3-amino-2-oxazolidinone (AOZ) side-chain that could be chemically released and then detected in liver, kidney and rump muscle tissues even 4 weeks after dosing. In tissues from animals killed at the end of the medication period, 993, 600 and 124 ng of AOZ were released from 1 g of liver, kidney and muscle respectively. In the tissues of the animals killed after a further 4 weeks the corresponding levels were 41, 7 and 10 ng/g respectively. It may be concluded that long withdrawal periods prior to slaughter for human consumption are required for pigs treated with furazolidone, because of the long residence time of protein-bound AOZ and the possibility that it might be released from its protein-bound form in the stomach and subsequently be transformed into a hydrazine.

Analysis of chimeric mRNAs derived from the STE3 mRNA identifies multiple regions within yeast mRNAs that modulate mRNA decay

In the yeast Saccharomyces cerevisiae unstable mRNAs decay 10-20 fold more rapidly than stable mRNAs. In order to examine the basis for the differences in decay rate of the unstable STE3 mRNA and the stable PGK1 and ACT1 mRNAs we have constructed and measured the decay rates of numerous chimeric mRNAs. These experiments indicate that multiple regions within yeast mRNAs are involved in modulating mRNA decay rates. Our results suggest that at least two regions within the STE3 mRNA are involved in stimulating rapid decay. One region is located within the coding region and requires sequences between codons 13 and 179. In addition, the STE3 3' UT can also function to stimulate decay. Surprisingly, the STE3 3' UT is not sufficient to accelerate the turnover of the stable PGK1 transcript unless portions of the PGK1 coding region are first deleted. These results not only identify sequences that function within yeast to stimulate mRNA turnover but also have important implications for an understanding of the basis of differences in eukaryotic mRNA decay rates.

Single dose oral fluconazole vs intravaginal terconazole in treatment of Candida vaginitis. Comparison and pilot study

Candida vaginitis develops in approximately one-fourth of women in their childbearing years. Conventional management consists of antifungal creams or tablets/suppositories administered intravaginally. Many patients have stated preferences for oral therapy. A randomized, double-blind placebo trial compared the efficacy of a single oral 200 mg dose of fluconazole with the application of terconazole 80 mg vaginal suppository daily for 3 days. Twenty-two patients (fluconazole = 12, terconazole = 10) were evaluated during a four-month period and favorable clinical responses were observed at both early and late evaluations. Mycologic cure was attained by 75% of the fluconazole group and 50% of the terconazole group at the early evaluation. At the late evaluation, mycologic cure was 75% and 100% respectively. The mean time to onset of symptom relief was 2.4 (1.7) days for the fluconazole group and 1.8 (1.8) days for the terconazole group. The mean time to complete relief of symptoms was 6.08 (2.84) and 6.6 (2.95) days respectively. A statistically significant difference did not exist for any of these measures. Seventy-three percent of the patients preferred oral therapy.

Postoperative radiation therapy after radical prostatectomy for prostate carcinoma

BACKGROUND

The role and benefit of adjuvant radiation therapy after radical prostatectomy is unclear. This role was evaluated in 58 patients who, after undergoing radical prostatectomy for prostate carcinoma, had local extension of disease beyond the prostate or positive surgical margins. Thirty-nine patients treated surgically alone were compared with 19 patients who received adjuvant postoperative radiation therapy. All patients were followed for at least 5 years, and 50 patients had 10-year follow-ups.

RESULTS

At 10 years, the actuarial local failure rate was 31% for patients treated with prostatectomy alone versus 6% for the group receiving postoperative radiation therapy (P less than 0.05). The actuarial survival and metastasis-free survival were similar for both groups. When patients with involved lymph nodes were excluded from analysis, the addition of radiation therapy resulted in improved recurrence-free survival (91% versus 46% at 10 years, P = 0.04) and in a trend toward improved metastasis-free survival (91% versus 55%, P = 0.08). Complications occurred in similar frequencies in both groups.

CONCLUSIONS

In patients with local disease extension or positive surgical margins after radical prostatectomy, adjuvant radiation therapy improved local control and was administered with acceptable side effects.