Alterations in hepatic perfusion resulting from splanchnic venous luminal compromise caused by pancreatic carcinoma

OBJECTIVE

We determined whether alterations in hepatic enhancement exist on dual phase helical CT of the liver in patients with splanchnic venous luminal compromise resulting from pancreatic adenocarcinoma.

SUBJECTS AND METHODS

We examined the extent of hepatic enhancement on dual phase helical CT in 22 patients with pancreatic adenocarcinoma. Eleven patients had splanchnic venous luminal narrowing (flattening along at least 120 degrees of the circumference) of the superior mesenteric vein with (n = 3) or without (n = 8) portal vein involvement caused by tumor. In the remaining patients, splanchnic vasculature appeared normal. An additional 16 patients without pancreatic or hepatic abnormality who underwent dual phase helical CT served as control subjects. We compared the extent of arterial phase and portal venous phase enhancement among the three groups.

RESULTS

The group of patients with splanchnic venous luminal compromise had significantly higher hepatic enhancement during the arterial phase (p < 0.01) and lower enhancement during the portal venous phase (p < 0.05) compared with the other two groups of patients. No significant difference in hepatic enhancement during either phase was noted between the control subjects and the patients with normal vasculature.

CONCLUSION

Because hepatic enhancement correlates with perfusion, splanchnic venous luminal compromise resulting from pancreatic adenocarcinoma likely causes decreased portal venous flow and compensatory increased hepatic arterial flow. This finding supports other evidence of a homeostatic mechanism that maintains hepatic perfusion.

Is CT angiography sufficient for prediction of resectability of periampullary neoplasms?

The optimal preoperative evaluation of periampullary neoplasms remains controversial. The aim of this study was to analyze the accuracy of helical computed tomography (CT) and CT angiography with three-dimensional reconstruction in predicting resectability. Between March 1996 and May 1999, a total of 100 patients with periampullary neoplasms were prospectively staged by helical CT and CT angiography with three-dimensional reconstruction. Vascular involvement was graded from 0 to 4, with grade 0 representing no vascular involvement and grade 4 total encasement of either the superior mesenteric vein or artery. Patients with grade 4 lesions were considered unresectable. Sixty-eight patients underwent surgical exploration with intent to perform a pancreaticoduodenectomy. Forty-four lesions were grade 0, five were grade l, eight were grade 2, and 11 were grade 3. Resectability for grades 0 to 3 was 96%, 100%, 50%, and 9%, respectively, for an overall resectability rate of 76%. Resectability in patients with vascular encroachment (grade 2) is usually determined by the extent of local disease rather than the presence of extrapancreatic disease. Resection is rarely possible in patients with evidence of vascular encasement (grade 3). Additional imaging modalities such as diagnostic laparoscopy are superfluous in patients with no evidence of local vascular involvement on CT angiography (grades 0 and 1) because of the high resectability rate and infrequency of unsuspected distant metastatic deposits.

Measuring self-efficacy in substance abuse intervention in obstetric practices

BACKGROUND

This study presents findings on the effect of an office-based obstetrics training program (given the acronym OBIWOM) on substance use assessment, management, and referral self-efficacy among obstetricians and staff of private, community-based obstetric practices.

METHODS

Participants were obstetricians and staff from 10 of 27 available community-based, private obstetric practices in the target areas, for a practice participation rate of 37%. This study used a delayed treatment design to compare self-efficacy between practice staff randomly assigned to an immediate or delayed intervention group.

RESULTS

Self-efficacy increased significantly after intervention from baseline to first follow-up for the immediate group, while no change was shown for the delayed (control) group. The impact of the intervention on self-efficacy was replicated in the assessment construct only after the intervention for the delayed group.

CONCLUSION

This research shows that education and training can effectively improve self-efficacy in obstetricians and their staff in the management of substance use and pregnancy.

Requirement for expert histopathological assessment of ovarian cancer and borderline tumors

The distinction between borderline ovarian tumours (BOT) and ovarian carcinoma is made by histopathological assessment. Of 64 patients managed according to institutional BOT protocols, 27 (42%) had been referred with a diagnosis of ovarian carcinoma that was subsequently changed to BOT following histopathological review. The 70% 6-year event-free survival of the patients with a revised diagnosis was not significantly different from those who were referred with a diagnosis of BOT. This change in diagnosis is important as it avoids the need for chemotherapy for most patients and results in patients receiving appropriate information concerning prognosis. Interestingly, 24 patients (38.1%) reported a family history of epithelial cancer, a finding that has not been reported previously. Campaign

A pilot study of the efficacy and tolerability of intralesional recombinant human beta-interferons in cervical intraepithelial neoplasia

Beta-interferons possess anti-viral, cell proliferation inhibition and immunomodulatory characteristics which may be of use in the treatment of cervical intraepithelial neoplasia (CIN). Intralesional administration may avoid systemic side effects. Twenty-six women with cervical punch biopsy proven CIN I and II were treated by interferon injection into the cervical transformation zone according to three dosage regimens--6 million international units (IU) weekly for six weeks, 9 million IU weekly for six weeks and 12 million IU bi-weekly for three weeks. At the last treatment visit, cervical cytology and biopsy were taken to ensure no disease progression and large loop excision of the transformation zone (LLETZ) was carried out six months after treatment. Therapy was well-tolerated with 93% of the scheduled 156 treatments given. Side effects which caused cessation of treatment included severe myalgia, headaches and prolonged flu-like symptoms. The 2 patients who failed to attend for LLETZ at six months and another 2 patients who received fewer than five scheduled treatments were excluded from analysis. LLETZ histology was negative in 12 patients (54%), showed inflammatory changes or squamous metaplasia in 4 (18%), was unchanged in 4 patients and had progressed in 2 (10%). Whilst intralesional beta-interferon clearly has activity in CIN, the response rate is less than that seen for excisional or ablative procedures. Nevertheless, it may have a role in the management of CIN where, for medical reasons of patient preference, there is a desire to avoid surgical therapy.

Magnetic resonance imaging of actinomycosis presenting as pelvic malignancy

Pelvic actinomycosis is associated with long-standing use of an intrauterine contraceptive device and may present with clinical signs and symptoms of pelvic malignancy. Diagnostic imaging can confirm the presence of a pelvic mass and tissue infiltration but findings are often non-specific. We present a case of pelvic actinomycosis with tubo-ovarian abscess in which magnetic resonance imaging demonstrated lower signal intensity tissue on T2 weighted sequences than would be typical for pelvic malignancy or infection and was useful in confirming regression of pelvic disease in response to antibiotic therapy.

FDA evaluations using in vitro metabolism to predict and interpret in vivo metabolic drug-drug interactions: impact on labeling

Recent advances in in vitro metabolism methods have led to an improved ability to predict clinically relevant metabolic drug-drug interactions. To address the relationships of in vitro metabolism data and in vivo metabolism outcomes, the Office of Clinical Pharmacology and Biopharmaceutics in the Center for Drug Evaluation and Research, Food and Drug Administration, evaluated a number of recently approved new drug applications. The goal of these evaluations was to determine the contribution of in vitro metabolism data in (1) predicting in vivo drug-drug interactions, (2) determining the need to conduct an in vivo drug-drug interaction study, and (3) incorporating findings into drug product labeling. Ten cases are presented in this article. They fall into two major groups: (1) in vitro data were predictive of in vivo results, and (2) in vitro data were not predictive of in vivo results. Discussion of these cases highlights factors limiting predictability of in vivo metabolic interactions from in vitro metabolism data. The integration of these findings into drug product labeling is also discussed.

Production of influenza-stimulated tumor necrosis factor-alpha by monocytes following acute influenza infection in humans

Tumor necrosis factor-alpha (TNF-alpha) is often measured in the serum or plasma of patients with severe infections, and marked elevation correlates with poor outcome. The relationship of TNF-alpha to protection from disease is frequently not observed because prospective studies of infectious agents are difficult to perform. We took advantage of a human antiviral influenza challenge study to correlate TNF-alpha production with seroconversion and symptom development. TNF-alpha production was measured by ELISA in the plasma compartment or was measured by intracellular production at the single cell level in the monocyte gated population. Monocyte TNF-alpha was associated with asymptomatic seroconversion, whereas there was no change in the plasma at the times measured. Measurement of TNF-alpha at the single cell level by flow cytometry may allow for better differentiation of the protective role of this cytokine in future studies.

Auditory preference for conspecific song in isolation-reared zebra finches

Seven female and six male zebra finches, Taeniopygia guttata, were reared in acoustic isolation from song and tested for their preference for conspecific song when 28-53 days old by allowing them to select exposure to zebra finch or European starling, Sturnus vulgaris, song. The birds hopped more frequently on a perch that generated zebra finch song than one that produced starling song, and they spent more time listening to zebra finch song. There were no sex differences. The results indicate that during their sensitive period for song learning, and prior to experience with song, zebra finches prefer conspecific song to heterospecific song. Copyright 1999 The Association for the Study of Animal Behaviour.

Adequacy of prenatal care and prescription of zidovudine to prevent perinatal HIV transmission

In 1994, data were published on the effectiveness of zidovudine in preventing perinatal transmission of HIV infection. Using data from surveillance projects in San Antonio, Dallas, and Houston, Texas, U.S.A., we linked records of children born from 1987 through 1996 with records of their HIV-infected mothers. Prenatal care was measured by Kotelchuck's Adequacy of Prenatal Care Utilization (APNCU) Index. We examined the association between adequacy of prenatal care and four measures of zidovudine prescription: prenatal, intrapartum, neonatal, and the complete regimen. Inclusion criteria was that the mother's HIV infection was diagnosed before a live birth; 221 mother-infant pairs were included in the analysis. Overall, 68% received inadequate or no prenatal care. Over time, the proportion of mother-infant pairs with adequate prenatal care doubled (24%-48%; relative risk [RR], 2.0; 95% confidence interval [CI], 1.3-3.0), and the proportion prescribed prenatal zidovudine tripled (20%-67%; RR, 3.4; 95% CI, 2.4-4.9). In logistic regression, APNCU (adjusted odds ratio [aOR], 2.6; 95% CI, 1.1-6.2) and time period (aOR, 19.9; 95% CI, 8.1-48.7) were associated with prenatal prescription of zidovudine. The benefits of prenatal care, including HIV testing and zidovudine treatment, underscore the urgent need to improve access to and use of prenatal care services.

Risk factors for foot blisters during road marching: tobacco use, ethnicity, foot type, previous illness, and other factors

Three hundred thirty-nine freshmen participating in cadet basic training at the U.S. Military Academy completed a questionnaire that asked them about their previous military experience, gender, ethnicity, injuries and illness experienced in the last 12 months, foot type, cigarette smoking habits, smokeless tobacco use, alcohol consumption, and sleep habits. They then performed a 21-km road march in about 6.5 hours. Their feet were examined for blisters before and after the march. Univariate analysis showed that risk factors for foot blisters included ethnicity (blacks at lower risk than others), a sickness in the last 12 months, no previous active duty military experience, use of smokeless tobacco, and flat feet (pes planus). Logistic regression indicated that all of these were independent blister risk factors with the exception of no previous active duty military experience.

Cytomegalovirus-specific IFNgamma and IL-4 are produced by antigen expanded human blood lymphocytes from seropositive volunteers

The cytokine responses to cytomegalovirus (CMV) antigen in seropositive and seronegative individuals were measured using a combination of antigenic expansion and intracellular staining. Intracellular IFNgamma and IL-4 were produced in a dose-dependent manner by T cells in response to CMV only in the seropositive population. The potential for individual cells to produce both Th1 and Th2 cytokines simultaneously was clear, as IL-4 was most often produced in those cells with the highest IFNgamma production. The cytokine-specific nature of this response was demonstrated by fluorescence microscopy, which showed granular cytoplasmic staining, and at the mRNA level by ribonuclease protection assays. These methods expand our ability to evaluate the immune response to CMV, and can now be correlated to a number of clinical conditions.

POU transcription factors control expression of CNS stem cell-specific genes

Multipotential stem cells throughout the developing central nervous system have common properties. Among these is expression of the intermediate filament protein nestin and the brain fatty acid binding protein (B-FABP). To determine if common mechanisms control transcription in CNS stem cells, the regulatory elements of these two genes were mapped in transgenic mice. A 257 basepair enhancer of the rat nestin gene is sufficient for expression throughout the embryonic neuroepithelium. This enhancer contains two sites bound by the class III POU proteins Brn-1, Brn-2, Brn-4, and Tst-1. Only one of the two POU sites is required for CNS expression. An adjacent hormone response element is necessary for expression in the dorsal midbrain and forebrain. The regulatory sites of the B-FABP gene are strikingly similar to those of the nestin gene. A hybrid POU/Pbx binding site is recognized in vitro by Pbx-1, Brn-1 and Brn-2. This site is essential for expression in most of the CNS. In addition, a hormone response element is necessary for forebrain expression. Both the nestin and B-FABP genes therefore depend on POU binding sites for general CNS expression, with hormone response elements additionally required for activity in the anterior CNS. These data indicate that regulation by POU proteins and hormone receptors is a general mechanism for CNS stem cell-specific transcription.

Influence of an antiperspirant on foot blister incidence during cross-country hiking

BACKGROUND

Rubbing moist skin results in higher frictional forces than rubbing very dry skin. As friction increases, the probability of activity-related blisters also increases. Therefore reducing moisture may reduce blister incidence during physical activity.

OBJECTIVE

We examined whether an antiperspirant can reduce foot blisters during hiking.

METHODS

In a double-blind study, cadets attending the US Military Academy were separated into two groups that used either an antiperspirant (20% aluminum chloride hexahydrate in anhydrous ethyl alcohol) or placebo (anhydrous ethyl alcohol) preparation. Cadets were told to apply preparations to their feet for 5 consecutive nights. On day 6, cadets completed a 21-km hike, and their feet were examined for blisters before and after.

RESULTS

Because of dropouts, the final sample size was 667 cadets with 328 in the antiperspirant group and 339 in the placebo group. There was a high rate of noncompliance with the treatment schedule: Cadets used the preparations from 0 to 5 nights before the hike. For cadets using the preparations at least 3 nights before the hike (n=269), the incidence of foot blisters was 21% for the antiperspirant group and 48% for the placebo group (P < 0.01). However, reports of skin irritation were 57% for the antiperspirant group and 6% for the placebo group (P < 0.01).

CONCLUSION

A 20% solution of aluminum chloride hexahydrate in anhydrous ethyl alcohol may be effective in reducing foot blisters during hiking; however, the side effect of skin irritation should be considered and preventive measures studied to reduce this irritation.

Using matrix-assisted laser desorption ionization mass spectrometry to map the quinol binding site of cytochrome bo3 from Escherichia coli

The cytochrome bo3 ubiquinol oxidase contains at least one and possibly two binding sites for ubiquinol/ubiquinone. Previous studies used the photoreactive affinity label 3-[3H]azido-2-methyl-5-methoxy-6-geranyl-1,4-benzoquinone (azido-Q), a substrate analogue, to demonstrate that subunit II contributes to at least one of the quinol binding sites. In the current work, mass spectroscopy is used to identify a peptide within subunit II that is photolabeled by the azido-Q. Purified cytochrome bo3 was photolabeled as previously described using azido-Q that was not tritiated (i.e., not radiolabeled). Subunit II was then isolated from an SDS-PAGE gel and proteolyzed in situ with trypsin. The resulting peptides were eluted from the gel and then identified using matrix-assisted laser desorption ionization mass spectrometry. The resulting mass spectrum was compared to that obtained by analysis of subunit II that had not been exposed to the photolabel. Using the amino acid sequence, each peak in the mass spectrum of the unlabeled subunit II could be assigned to an expected trypsin fragment. Two additional peaks were observed in the mass spectrum of the photolabeled subunit with m/z 1931.9 and 2287.7. Subtraction of the mass of azido-Q from the peak at m/z 1931.9 results in a mass equivalent to that of a peptide consisting of amino acids 165-178. The assignment of the peak at m/z 2287.7 cannot be made unequivocally and may correspond either to the covalent attachment of azido-Q to peptide 254-270 or to a peptide resulting from incomplete proteolysis. The labeled peptide, 165-178, is within the water-soluble domain of subunit II, whose X-ray structure is known. This peptide is located near the site where CuA is located in the homologous cytochrome c oxidases and can be placed near the interface between subunits I and II.

Hypoalgesia in mice with a targeted deletion of the tachykinin 1 gene

The tachykinin neuropeptides, substance P and substance K, are produced in nociceptive primary sensory neurons and in many brain regions involved in pain signaling. However, the precise role and importance of these neuropeptides in pain responses has been debated. We now show that mice that cannot produce these peptides display no significant pain responses following formalin injection and have an increased pain threshold in the hotplate test. On the other hand, the mutant mice react normally in the tail flick assay and acetic acid-induced writhing tests. These results demonstrate that substance P and/or substance K have essential functions in specific responses to pain.

The feasibility of assessing women's perceptions of the risks and benefits of fertility drug therapy in relation to ovarian cancer risk

OBJECTIVE

To determine the feasibility of asking women undergoing fertility treatment the maximum increased risk of ovarian cancer they would be willing to tolerate in order to take ovulation-induction drugs.

DESIGN

A prospective pilot study of women attending fertility clinics over a 2-month period.

SETTING

Two tertiary care fertility clinics in Toronto.

PATIENT(S)

Sixty-one English-speaking women were approached and 85% (n = 52) were enrolled.

INTERVENTION(S)

A self-administered questionnaire with fertility-specific questions. Thirty-eight women also were asked to complete standardized scales of anxiety and optimism.

MAIN OUTCOME MEASURE(S)

Women's report of the maximum level of lifetime risk of ovarian cancer they were willing to tolerate in order to undergo fertility treatment.

RESULT(S)

Seventy-nine percent were willing to accept an increased risk of ovarian cancer. Only 24% understood that treatment for ovarian cancer usually was not curative.

CONCLUSION(S)

A majority of patients were willing to tolerate a modest increase in their lifetime risk of ovarian cancer because of fertility treatment, most basing their estimate of acceptable risk on limited awareness of the issue.

Resource utilization among neonatologists in a university children's hospital

OBJECTIVE

We studied factors affecting length of hospital stay and resulting hospital charges among patients managed by two separate groups of neonatologists in the same academic health science center.

DESIGN

Retrospective analysis of clinical and financial data base information.

METHODS

Neonatal intensive care was provided in the same acute care nursery in a large university children's hospital by: (1) neonatologists in a full-time academic division (group A) and (2) a group associated with a private managed care organization (group B). Clinical and financial parameters of all neonates admitted in fiscal year 1994 were compared for the two provider groups. Stepwise regression analysis was used to evaluate factors influencing hospital charges and length of hospital stay (LOS) and to adjust for differences in clinical variables between the two groups.

RESULTS

Group A physicians provided care for 340 infants, while 137 were treated by those of group B. Group A included older patients, more outborns, more level III patients, more sepsis, more intermittent positive pressure ventilation, and more patent ductus arteriosus. The incidence of transient tachypnea of the newborn was higher among group B patients. Hospital charges were primarily determined by LOS, which was similar for the two groups. When the data were corrected for differences in risk and patient acuity, however, a significant relationship between physician group and LOS was demonstrated, with LOS being an average of 7.8 days shorter for group A. A net reduction of $3 114 969 in hospital charges might have been realized had group A physicians provided care for all study patients.

CONCLUSIONS

Hospital charges were determined by LOS. In this setting, academic neonatologists produced shorter LOS and comparable clinical outcomes, despite caring for a population at greater risk. The reduction in LOS could have resulted in more than $3.1 million in annualized savings had the academic group provided care for all of the study patients.

Regulation of RAR beta 2 mRNA expression: evidence for an inhibitory peptide encoded in the 5'-untranslated region

Regulation of mRNA translation and stability plays an important role in the control of gene expression during embryonic development. We have recently shown that the tissue-specific expression of the RAR beta 2 gene in mouse embryos is regulated at the translational level by short upstream open reading frames (uORFs) In the 5'-untranslated region (Zimmer, A., A.M. Zimmer, and K. Reynolds. 1994. J. Cell Biol. 127:1111-1119). To gain insight into the molecular mechanism, we have performed a systematic mutational analysis of the uORFs. Two series of constructs were tested: in one series, each uORF was individually inactivated by introducing a point mutation in its start codon; in the second series, all but one ORF were inactivated. Our results indicate that individual uORFs may have different functions. uORF4 seems to inhibit translation of the major ORF in heart and brain, while uORFs 2 and 5 appear to be important for efficient translation in all tissues. To determine whether the polypeptide encoded by uORF4 or the act of translating it, is the significant event, we introduced point mutations to create silent mutations or amino acid substitutions in uORF4. Our results indicate that the uORF4 amino acid coding sequence is important for the inhibitory effect on translation of the downstream major ORF.

Load carriage using packs: a review of physiological, biomechanical and medical aspects

This paper reviews the biomedical aspects of transporting loads in packs and offers suggestions for improving load-carriage capability. Locating the load mass as close as possible to the body center of gravity appears to result in the lowest energy cost when carrying a pack. Thus, the double pack (half the load on the front of the body and half the load on the back) has a lower energy cost than the backpack. However, backpacks provide greater versatility in most situations. The energy cost of walking with backpack loads increases progressively with increases in load mass, body mass, walking speed or grade; type of terrain also influences energy cost. Predictive equations have been developed for estimating the energy cost of carrying loads during locomotion but these may not be accurate for prolonged (>2 h) or downhill carriage. Training with loads can result in greater energy efficiency since walking with backpack loads over several weeks decreases energy cost. Load-carriage speed can be increased with physical training that involves regular running and resistance training. Erector spinae electrical activity (EMG) is lower during load carriage than in unloaded walking until loads exceed 30-40 kg, at which point erector spinae EMG activity is higher than during unloaded walking. EMGs of the quadriceps and gastrocnemius, but not the tibialis anterior or hamstrings, increase with load. Framed packs with hip belts reduce the electrical activity of the trapezius muscles, presumably by shifting forces from the shoulders to the hips. Increases in the backpack load mass result in increases in forces exerted on the grounds, amount of knee flexion and the forward inclination of the trunk. Compared to backpacks, double packs produce fewer deviations from normal walking. Common injuries associated with prolonged load carriage include foot blisters, stress fractures, back strains, metatarsalgia (foot pain), rucksack palsy (shoulder traction injury) and knee pain. Closed-cell neoprene insoles and use of an acrylic or nylon sock, combined with a wool sock, reduce blister incidence. A framed pack with a hip belt reduces the incidence of rucksack palsy. Backpack load carriage can be facilitated by lightening loads, optimizing equipment, improving load distribution and by preventive action aimed at reducing the incidence of injury.

Generation and characterization of monoclonal antibodies to human type-5 tartrate-resistant acid phosphatase: development of a specific immunoassay of the isoenzyme in serum

We have characterized four monoclonal antibodies (mAbs) to the purple ("tartrate-resistant," band 5) acid phosphatase of the human osteoclast (TRAP) and used these to develop a specific serum immunoassay. All four mAbs are of high affinity (Ka = 1-5 x 10(8) L/mol) with a very fast Kassoc (0.2-2.0 x 10(5) L mol-1 s-1) and a moderate Kdissoc (1-3 x 10(-3) s). Two of the mAbs were selected to develop a time-resolved fluorescence immunoassay to measure serum concentrations of TRAP. The mean serum immunoreactive TRAP in a group of healthy premenopausal women and men was 3.7 +/- 1.8 micrograms/L (mean +/- SD) and 3.5 +/- 1.6 micrograms/L, respectively. Significantly higher concentrations of TRAP were found in postmenopausal women (6.3 +/- 2.3 micrograms/L) and in eight patients with Gaucher disease (19.3 +/- 4.7 micrograms/L). Further studies are required to investigate the value of serum TRAP as a marker of bone resorption.

Effects of an antiperspirant with emollients on foot-sweat accumulation and blister formation while walking in the heat

BACKGROUND

Friction blisters are a common injury in sports activities and military operations. Blisters can compromise performance, so it is important to devise preventive strategies to reduce these injuries.

OBJECTIVE

This study investigated the influence of an antiperspirant with emollient additives on frequency and severity of friction blisters, hot spots, and irritant dermatitis.

METHODS

Twenty-three healthy men walked on a treadmill (1.39 m/sec, 1% grade) in a warm environment (28 degrees C, 25% relative humidity) carrying a total mass of 21 +/- 1 kg. For 4 consecutive days before the walk, the subjects' feet were treated with either (1) an antiperspirant (20% aluminum zirconium tetrachlorohydrex glycine concentration plus water) with emollient additives, (2) emollient additives alone (placebo control), or (3) nothing (nontreated). In two separate trials (1 month apart) each participant received the antiperspirant treatment and both control treatments (emollient [placebo] and no treatment).

RESULTS

No differences were seen among treatment conditions for sweat accumulation (p = 0.86), blister incidence (p = 0.36), hot spot incidence (p = 0.83), or blister severity (p = 0.31). Irritant dermatitis was not reported in any of the treatment conditions.

CONCLUSION

The use of an antiperspirant with emollients reduces irritant dermatitis but does not reduce total foot-sweat accumulation, blister or hot spot incidence, or blister severity.

Generation and characterization of monoclonal antibodies to human type-5 tartrate-resistant acid phosphatase: development of a specific immunoassay of the isoenzyme in serum

We have characterized four monoclonal antibodies (mAbs) to the purple ("tartrate-resistant," band 5) acid phosphatase of the human osteoclast (TRAP) and used these to develop a specific serum immunoassay. All four mAbs are of high affinity (Ka = 1-5 x 10(8) L/mol) with a very fast Kassoc (0.2-2.0 x 10(5) L mol-1 s-1) and a moderate Kdissoc (1-3 x 10(-3) s). Two of the mAbs were selected to develop a time-resolved fluorescence immunoassay to measure serum concentrations of TRAP. The mean serum immunoreactive TRAP in a group of healthy premenopausal women and men was 3.7 +/- 1.8 micrograms/L (mean +/- SD) and 3.5 +/- 1.6 micrograms/L, respectively. Significantly higher concentrations of TRAP were found in postmenopausal women (6.3 +/- 2.3 micrograms/L) and in eight patients with Gaucher disease (19.3 +/- 4.7 micrograms/L). Further studies are required to investigate the value of serum TRAP as a marker of bone resorption.

Compatibility of high-intensity strength and endurance training on hormonal and skeletal muscle adaptations

Thirty-five healthy men were matched and randomly assigned to one of four training groups that performed high-intensity strength and endurance training (C; n = 9), upper body only high-intensity strength and endurance training (UC; n = 9), high-intensity endurance training (E; n = 8), or high-intensity strength training (ST; n = 9). The C and ST groups significantly increased one-repetition maximum strength for all exercises (P < 0.05). Only the C, UC, and E groups demonstrated significant increases in treadmill maximal oxygen consumption. The ST group showed significant increases in power output. Hormonal responses to treadmill exercise demonstrated a differential response to the different training programs, indicating that the underlying physiological milieu differed with the training program. Significant changes in muscle fiber areas were as follows: types I, IIa, and IIc increased in the ST group; types I and IIc decreased in the E group; type IIa increased in the C group; and there were no changes in the UC group. Significant shifts in percentage from type IIb to type IIa were observed in all training groups, with the greatest shift in the groups in which resistance trained the thigh musculature. This investigation indicates that the combination of strength and endurance training results in an attenuation of the performance improvements and physiological adaptations typical of single-mode training.

Maintenance requirements for dietary protein in 11- and 18-month-old male rats

Body weight, lean body mass (total weight less body fat), carcass protein, and serum protein were examined as potential parameters by which to assess the effect of age on protein requirements for maintenance in male rats, aged 11 months and 18 months, fed diets containing 1.53, 3.41, 4.98, 6.52, or 8.05% dietary protein, casein plus methionine, for a 5-week period. Body weight change was maintained in older animals at 6.52% dietary protein and in younger animals at 4.98% dietary protein. Older animals consuming the two diets highest in protein had a greater percent body fat and less percent body protein than younger animals. Significant effects of diet and the interaction of diet and age on serum protein were also observed. As dietary protein level increased, serum protein increased gradually in younger rats, but only between 3.41 and 4.98% dietary protein in older rats. Lean body mass and total carcass protein increased as dietary protein level increased, but there were no significant differences due to age or the interaction of diet and age. Changes in body weight indicate a greater protein requirement for 18-month-old rats compared with 11-month-old rats, although complicated by greater food intake and fat deposits in older animals. Measures of body protein indicate that age has some influence on protein needs for maintenance purposes.

Tissue specific expression of the retinoic acid receptor-beta 2: regulation by short open reading frames in the 5'-noncoding region

The 40-S subunit of eukaryotic ribosomes binds to the capped 5'-end of mRNA and scans for the first AUG in a favorable sequence context to initiate translation. Most eukaryotic mRNAs therefore have a short 5'-untranslated region (5'-UTR) and no AUGs upstream of the translational start site; features that seem to assure efficient translation. However, approximately 5-10% of all eukaryotic mRNAs, particularly those encoding for regulatory proteins, have complex leader sequences that seem to compromise translational initiation. The retinoic-acid-receptor-beta 2 (RAR beta 2) mRNA is such a transcript with a long (461 nucleotides) 5'-UTR that contains five, partially overlapping, upstream open reading frames (uORFs) that precede the major ORF. We have begun to investigate the function of this complex 5'-UTR in transgenic mice, by introducing mutations in the start/stop codons of the uORFs in RAR beta 2-lacZ reporter constructs. When we compared the expression patterns of mutant and wild-type constructs we found that these mutations affected expression of the downstream RAR beta 2-ORF, resulting in an altered regulation of RAR beta 2-lacZ expression in heart and brain. Other tissues were unaffected. RNA analysis of adult tissues demonstrated that the uORFs act at the level of translation; adult brains and hearts of transgenic mice carrying a construct with either the wild-type or a mutant UTR, had the same levels of mRNA, but only the mutant produced protein. Our study outlines an unexpected role for uORFs: control of tissue-specific and developmentally regulated gene expression.

The epidemiology of Lyme disease in Delaware 1989-1992

OBJECTIVES

The study was conducted to describe the temporal, geographic, demographic and treatment characteristics of Lyme disease in Delaware and to assist health planners in developing and implementing control strategies.

METHODS

All physician-submitted Centers for Disease Control and Prevention (CDC) follow-up Lyme disease report forms from 1989 through 1992 were reviewed for completeness. Data were gathered from completed forms only. All cases were classified according to the 1990 CDC surveillance case definition. Cases were further subdivided into two groups. Antibiotic usage patterns were then identified for each group. Data on the percentage of infected ticks by county were obtained from a 1988 study conducted by the University of Delaware; Delaware Health and Social Services, Division of Public Health; and the Department of Natural Resources and Environmental Control.

RESULTS

Reported cases of Lyme disease increased 246 percent between 1989 and 1992. The 1992 statewide incidence rate was 12.6 cases per 100,000 population. Whites were four times more likely to contract Lyme disease than were blacks. The majority of cases were reported between June and October. The number of patients being treated with oral antibiotics for localized disease for three weeks or longer increased from 52 percent in 1991 to 94 percent in 1992. Ixodid ticks infected with Borrelia burgdorferi were found in all three counties.

CONCLUSION

The Delaware State Board of Health made Lyme disease reportable in September 1989. This requirement increased the quality of Lyme disease surveillance; however, the disease is probably under-reported since Delaware does not actively solicit Lyme disease reports. Delaware's case data reflect national data which indicate an increase in reported cases. A trend toward longer duration of treatment for localized Lyme disease is evident.

Association of ovarian malignancy with expression of platelet-derived endothelial cell growth factor

BACKGROUND

At the present time, the pathogenesis of ovarian cancer remains poorly understood, with invasive diagnosis and ineffective treatment for women with the disease. Despite scientific and medical advances in oncology, the overall 5-year survival rate of 30% for ovarian cancer patients has not changed in 20 years. An understanding of the angiogenic process as it occurs in ovarian cancer would not only increase our knowledge of the pathogenesis of this cancer but also might offer novel opportunities for therapeutic intervention.

PURPOSE

Our aim was to study the expression of messenger RNA (mRNA) coding for four putative angiogenic factors in normal ovaries and benign and malignant ovarian tumors: platelet-derived endothelial cell growth factor (thymidine phosphorylase), vascular endothelial growth factor, basic fibroblast growth factor, and transforming growth factor-beta 1.

METHODS

Four normal ovaries and 25 tumors (seven benign, one of borderline malignancy, and 17 malignant) were collected from 29 patients during elective oophorectomy. The site of sampling (areas of high-velocity blood flow) was directed by transvaginal color Doppler imaging performed within 24 hours of the surgery. Increased blood flow within the tissues was demonstrated by the presence of color (i.e., the velocity was > 7 cm/s) and, together with a pulsatile index of less than 1.0, constituted a positive scanning result. In scan-positive tissues, the area of maximum blood flow was chosen. In scan-negative tissues, a solid area was chosen in complex lesions, or the cyst wall was chosen in simple lesions. Ovarian RNA was subsequently extracted from areas of high-velocity flow (i.e., tissues with a positive scanning result) or from solid areas or septa in tissues with a negative scanning result. A ribonuclease protection assay was used to assess the expression of mRNA coding for the four angiogenic factors.

RESULTS

Two normal ovaries (containing a corpus luteum) and one benign and 17 malignant tumors (plus the borderline) gave a positive scanning result. There was a significant difference between the expression of mRNA for platelet-derived endothelial cell growth factor between scan-positive and scan-negative tissues (P < .001) and between benign and malignant tumors (P < .001).

CONCLUSIONS

Areas of high blood velocity in ovarian tumors are associated with increased expression of platelet-derived endothelial cell growth factor.

IMPLICATIONS

Drugs that affect the angiogenic activity of platelet-derived endothelial cell growth factor offer a potential route for therapeutic intervention.

Host fidelity is an effective premating barrier between sympatric races of the apple maggot fly

Models of sympatric speciation for phytophagous insects posit a central role for host plant-associated mating as a premating isolating mechanism in lieu of geographic barriers to gene flow. Here, by means of three mark-and-recapture studies, we confirm that host fidelity (i.e., the tendency of an insect to reproduce on the same host species that it used in earlier life-history stages) restricts gene flow between sympatric apple- and hawthorn-infesting races of Rhagoletis pomonella (Diptera: Tephritidae) to approximately 6% per generation. Genetically based differences in host preference, adult eclosion under the "correct" host species, and allochronic isolation contribute to host fidelity in various degrees in the races. The results verify that host-associated adaptation can produce reproductive isolation as a correlated character (a key premise of sympatric speciation). The study also represents one of the few or perhaps only example in animals where the intra-specific isolating effects of specific phenotypes have been quantified in nature.

Gene targeting constructs: effects of vector topology on co-expression efficiency of positive and negative selectable marker genes

Targeting of DNA into specific chromosomal loci often involves the use of a negative selectable marker gene to enrich for cell clones that have undergone homologous recombination. In this study we asked if the arrangement of the positive and negative markers in 'knockout' constructs can influence the expression of a lacZ gene that was used as a negative marker. We show that constructs which differ only in their topology have vastly different co-expression efficiencies. The site of DNA linearization was critical. While linearizing at the 5'-end of the lacZ gene was compatible with efficient lacZ expression, linearizing at the 3'-end was always detrimental. We also demonstrate that the topology of the template was more important than the promoter used to drive lacZ expression.

The potential role of serum CA 125 in an ultrasound-based screening program for familial ovarian cancer

We have assessed the potential role of a test based upon the measurement of serum CA 125 in an ultrasound-based screening program for familial ovarian cancer. A sample of peripheral blood was taken from 1502 self-referred, asymptomatic women whose pedigree showed that at least one close relative had developed the disease. All women in the study underwent one screening by transvaginal ultrasonography (consisting of one or more scans) to detect any persistent lesion and a change in ovarian volume. Women with a positive result were referred for surgery. The concentration of serum CA 125 was measured in all samples at the end of the study. Seven ovarian cancers (4 invasive and 3 of borderline malignancy; 5 FIGO stage Ia, 1 stage IIa, 1 stage III) and 55 benign lesions were detected. We calculated the effect that a prescreening test (based on different threshold values for serum CA 125) would have had on the number of women entering the ultrasound-based screening program, and on the detection rate and false-positive rate of the overall procedure. There was a direct relationship between the number of women referred for ultrasound screening and the detection rate. The use of a threshold value for serum CA 125 > or = 20 U/ml would have meant that 380 women (25.3%) were referred for ultrasonography and 5 out of 7 cancers (71%) would have been detected with a false-positive rate of 1.1%. The odds of a woman with a positive screening result having cancer at surgery would have been about 1:3 (which would improve to about 1:1 if observational indices of color Doppler imaging and a morphological score had been used throughout). We concluded that a prescreening immunochemical test based on the measurement of serum CA 125 (with a threshold value of > or = 20 U/ml) would increase the prior odds for familial ovarian cancer by 2.8, but would lower the overall detection rate by 29% at the prevalence screening.

Whole chromosome 17 loss in ovarian cancer

Chromosomal deletions, associated with the loss of normal function of tumour suppressor genes, have been identified in a variety of both familial and sporadic human cancers. Although the molecular pathology of ovarian cancer is not understood, several studies have reported deletions in chromosome 17 in ovarian tumours. We have used 13 restriction site polymorphic, microsatellite, and variable number tandem repeat markers to make a detailed analysis of chromosome 17 deletions in 12 benign and 19 malignant ovarian tumours. Two benign and 11 malignant tumours were informative for at least one marker on each arm of the chromosome. Loss of heterozygosity (LOH) was detected in both arms (by all informative markers) in 5 malignant tumours from four women (three with the disease at FIGO stage Ia). In a further bilateral ovarian tumour a partial LOH affecting 17q22-q25 was present in one ovary only. By contrast to a number of previous studies, none of the 19 malignant and 12 benign tumours showed ERBB2 (17q12-22) amplification. The data presented show that the loss of a whole copy of chromosome 17 is a frequent and relatively early event in the development of some ovarian cancers. This suggests the possible involvement of multiple chromosome 17 loci in the pathogenesis of ovarian cancer. Equally plausible is that the loss of a whole chromosome copy could be the product of chromosomal instabilities induced by loss of the normal allele of tumour suppressors, such as TP53, located on this chromosome.

Tetanus toxin light chain expression in Sertoli cells of transgenic mice causes alterations of the actin cytoskeleton and disrupts spermatogenesis

Tetanus toxin is a powerful neurotoxin known to inhibit neurotransmitter release. The tetanus toxin light chain is a metalloprotease that cleaves some members of the synaptobrevin gene family with high specificity. Here, we report the expression of a synthetic gene encoding the tetanus toxin light chain in the seminiferous epithelium of transgenic mice. Spermatogenesis was severely impaired and mature spermatozoa were completely absent. Late spermatids exhibited pleomorphic shapes and acrosomal distortions. The number of Leydig cells was greatly increased. In situ hybridization analysis revealed that the toxin acts on Sertoli cells. Affected cells exhibited an aberrant distribution of actin filaments and many cells contained large vacuoles. Our results demonstrate that tetanus toxin is active in non-neuronal cells and suggest an important function for members of the synaptobrevin gene family during the late stages of spermatogenesis.

Physical fitness, age, and injury incidence in infantry soldiers

Injuries are a common occurrence in young, active civilian and military populations. This study examined injury incidence and the association of musculoskeletal injuries with age and physical fitness in soldiers. Subjects were a cohort of 298 male soldiers assigned to an infantry battalion in Alaska. The soldiers' ages were obtained from the battalion records and their physical fitness was assessed from 2-mile run times, sit-ups, and push-ups. Injuries were documented from a retrospective review of the soldiers' medical records for a 6-month period (October to March) before the fitness testing. Fifty-one percent of the soldiers suffered one or more injuries. The most common injury diagnosis was musculoskeletal pain, followed by strains, sprains, and cold-related injuries. Soldiers experienced a total of 212 separate injuries, which resulted in 1764 days of limited duty. The crude annualized injury rate was 142 injuries per 100 soldiers (one soldier could experience more than one type of injury). The proportion of soldiers injured decreased as age increased. Slower 2-mile run times and fewer sit-ups were associated with a higher incidence of musculoskeletal injuries. This study documents the injury incidence in infantry soldiers and identifies younger age and low physical fitness as potential risk factors for these injuries.

Screening for early ovarian cancer

Transvaginal ultrasound scanning with colour Doppler imaging can be used to detect early ovarian cancer. About one in three women with a family history of the disease and a positive screening result (i.e. a persistent intraovarian mass with a characteristic blood supply) will have histological signs of primary cancer. A randomized controlled clinical trial should be undertaken to assess whether screening and immediate treatment of women from the general population will improve survival rates from the disease.

The sit-up test: an alternate clinical test for evaluating pediatric torticollis

The sit-up test, a new evaluation method for differentiating between ocular and orthopaedic torticollis, was evaluated against the monocular occlusion test, using results of three-step testing for standardization. The study group consisted of 31 patients with torticollis between the ages of 4 and 12.5 years. Subjects were selected based only on their ability to cooperate with three-step testing. Three-step testing identified 27 of the 31 patients as having ocular torticollis, with the remaining 4 having an orthopaedic etiology. Sit-up testing correctly identified all 27 ocular torticollis patients, with no false positives or false negatives. Monocular occlusion testing detected at best 22 (81.4%) of the ocular torticollis patients, with no false positives.

Efficacy of antiperspirants on feet

Nineteen male soldiers participated in a study of the effectiveness of two antiperspirants (aluminum chlorohydrate and aluminum zirconium tetrachlorohydrex glycine) in reducing foot-sweat accumulation and injuries. Each subject was tested before and after antiperspirant application, with a 1-hour treadmill march at 5.6 km/hour in a warm environment. Both antiperspirants decreased (p less than 0.05) foot-sweat accumulation over 50%. There was also a tendency, although not statistically significant, for subjects to incur fewer blisters with antiperspirant use. However, the antiperspirants also increased (p less than 0.05) the incidence of irritant dermatitis. Nevertheless, these data suggest that the application of antiperspirants to the feet has merit in reducing serious foot injuries (blisters, trench foot) exacerbated by wet feet.

Injuries associated with strenuous road marching

Injuries were recorded during and up to 12 days after a maximal effort road march. Light infantry soldiers (N = 335) carried a total load of 46 kg over a 20 km course. Twenty-four percent of the soldiers suffered one or more injuries, resulting in 44 days of limited duty. All injuries involved the lower extremities and/or the back. Foot blisters and back problems were the most common complaints (35% and 23%, respectively, of the total injuries). These data indicate that units without recent road marching training can expect a high incidence of injuries as a result of a single demanding road march.

Epidural insertion: how far should the epidural needle be inserted before testing for loss of resistance?

The aim of this study was to determine the depth to which an epidural needle can safely be inserted before testing for loss of resistance. This ensures that the epidural needle is advanced far enough to encounter ligament thus avoiding the confusion that can occur when testing for loss of resistance whilst still in subcutaneous tissues. A survey of the distance between the skin and the epidural space in 400 obstetric patients was performed. Three hundred and ten midline epidurals showed a highly significant correlation (P<0.001) between the patient's pregnant weight and the distance to the epidural space. Using these data confidence limits were calculated in order to quantify the distance that the epidural needle could safely be inserted before testing for loss of resistance. Dividing the patient's pregnant weight by 25 will give this distance in centimetres. Seventy six paramedian approaches were performed and a less good correlation was found between the depth of the space and the woman's weight. There was no correlation with height or foot size.

Activity of the beta-retinoic acid receptor promoter in transgenic mice

LacZ reporter gene constructs were used to analyze the murine retinoic acid receptor beta (mRAR beta) gene promoter in transgenic mice. LacZ expression in transgenic mouse embryos with 250 bp of promoter sequences closely parallels that of RAR beta between embryonic days 8.5 and 12.5. This indicates that the -1 to -250 promoter region contains most regulatory elements required for tissue specific expression. Additional elements in the -250 to -625 region are required for high expression levels after day 12.5. Elements in the -625 to -3100 region are necessary to reproduce the RAR beta expression in the meninges and the eye mesenchyme. The expression pattern of the transgene and the endogenous RAR beta, as revealed by in situ hybridization, suggests an important role of the RAR beta in the developing nervous system.

Paracetamol-associated luteinized unruptured follicle syndrome: effect on intrafollicular blood flow

We are using transvaginal ultrasonography with color Doppler imaging to study changes in intrafollicular blood flow over the periovulatory period. We report here the findings from one volunteer (subject 9), who took two tablets of paracetamol (1000 mg) twice daily (between 07.00 and 08.00, and 18.00 and 19.00) for 2 consecutive menstrual cycle days (12 and 13) to alleviate a headache, which was shown retrospectively to have occurred within the duration of the luteinizing hormone (LH) surge in peripheral plasma. The drug appeared to have a profound effect on peak systolic blood velocity within the preovulatory follicle. Color (an index of blood velocity) disappeared and flow velocity waveforms were not detectable for at least 4 h. Color then re-appeared, but the peak systolic blood velocity had reduced by 69.8% (from 18.2 to 5.5 cm/s). The peak systolic blood velocity recovered subsequently to 16.3 cm/s, but the follicle did not rupture and continued to grow to a maximum diameter > 59 mm. There was no apparent effect of the drug on expected changes in the circulating levels of estradiol, LH, follicle stimulating hormone or progesterone. The secretory phase of the menstrual cycle lasted 13 days (i. e. day of LH peak to day of next menses minus one). We suggest that paracetamol taken at the time of the LH surge may affect intrafollicular peak systolic blood velocity and might inhibit ovulation. Possible molecular mechanisms are discussed.