"Moving Away From Cancer" Prospective Exercise Trial for Female Rural Cancer Survivors: How Can We Step It Up?

PURPOSE

This prospective trial's objective was to determine feasibility and outcomes of an exercise-based intervention for rural overweight/obese female cancer survivors.

MATERIALS AND METHODS

Survivors of endometrial, breast, or ovarian cancer enrolled in a 6-month program of increased aerobic activity (30 minutes daily walking) and strength-training exercises using exercise bands (THERABAND; Akron, OH) with personalized telephone motivational coaching. Baseline demographics, anthropomorphic measurements, quality of life (QOL), fitness, and readiness to adopt exercise changes were assessed; daily steps, band use, and follow-up measurements were assessed at 3 and 6 months. Study completion was modeled using logistic regression.

RESULTS

The mean age of the 99 women was 59.9 years, the mean body mass index (BMI) was 35.9 kg/m², 88.9% were white, and 41.4% reported current exercise. Fifty-five women (55.6%) completed the 6-month program, and 36 (36.4%) completed exercise interventions. Using logistic regression to model study completion, only baseline QOL scores (physical component summary) and mental component summary) remained significant predictors. The mean weight change was a gain (0.88 kg). Higher MCS baseline scores and prior regular exercise predicted continued exercise and increased step counts, whereas higher BMI and baseline sleep predicted decreased QOL. Top walking barriers were feeling unwell and weather; barriers to strength exercises were band dislike and pain.

CONCLUSION

The most significant predictor of trial completion and improved exercise outcomes was a higher baseline mental QOL. Motivation, belief in the importance of exercise, and prescribed/monitored exercise regimens were not sufficient; supportive and cognitive behavioral therapy interventions for survivors are needed to sustain uptake.

Evaluation of breast screening strategies in a high risk breast and ovarian cancer clinic

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BRCA mutation carriers are more likely to be diagnosed with breast cancer compared to high-risk non-BRCA carriers.

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MRI was able to effectively identify DCIS in the BRCA population.

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In BRCA mutation carriers younger than 40, there were no MRI occult cancers found.

Recent data suggest that BRCA mutation carriers younger than 40 may not benefit from mammography in addition to MRI. Our objective was to evaluate screening modalities utilized in a high-risk population. Clinicopathologic data were abstracted for patients followed in a high risk clinic from 2007 to 2017. Descriptive statistics were calculated and associations between categorical variables were evaluated using chi-square tests. 631 women comprised the study population; 496 patients had no known mutation (79%), 128 (20%) had a BRCA mutation, and 7 patients had other deleterious mutations. BRCA mutation carriers were more likely to have cancers diagnosed after mammogram callbacks (p = 0.0046) and biopsies (p = 0.0026) compared to non-BRCA mutation carriers. BRCA mutation carriers were also more likely to have cancers diagnosed after biopsies following screening MRI (p = 0.045). 13 BRCA patients were diagnosed with cancer (average age 51). Of the cancers diagnosed after abnormal MRI, 3 were DCIS; all 3 patients had a normal mammogram 4–6 months prior. In those found after abnormal mammogram (n = 6), follow up MRI was performed in 4 cases; all demonstrated the lesion. Three patients were diagnosed younger than 40, 1 on mammogram and 2 on MRI. The patient diagnosed on mammogram had no prior MRI and the lesion was seen on follow-up MRI. Interval screening MRI identified DCIS in BRCA patients with a previous normal mammogram and cancers diagnosed on mammogram were all identified on follow-up MRI. These findings support further evaluation of MRI alone until age 40 in BRCA mutation carriers.

Evaluation of screening and risk-reducing surgery for women followed in a high-risk breast/ovarian cancer clinic: it is all about the tubes in BRCA mutation carriers

The objectives of this study were to determine both surgical and subsequent cancer outcomes for high-risk women from the University of Virginia's High-Risk Breast/Ovarian Cancer clinic undergoing ovarian cancer risk-reducing surgery. Retrospective review identified high risk women who had ovarian risk reducing surgery over the past decade and surgical outcomes, pathology, pre-operative screening results, and pre-/post-operative cancer diagnoses were evaluated. One hundred and eighty-three high-risk women had risk reducing surgery at a mean age of 50.1 years and with a mean BMI of 28.9 kg/m2 at the time of surgery. Most women (103; 56.3%) had a strong family history of cancer concerning for a hereditary syndrome without an identified mutation, 35.5% of women carried a known deleterious mutation and 7.7% of women had a personal history of breast or ovarian cancer. The most common procedure was a risk-reducing bilateral salpingo-oophorectomy with or without hysterectomy (RRBSO, 89.1%). All women underwent the Sectioning and Extensively Examining the Fimbriated End (SEE-FIM) pathology protocol which found two (1.1%) invasive ovarian cancers (one ovarian/tubal carcinosarcoma, one granulosa cell ovarian cancer), three (1.6%) serous tubal intraepithelial carcinomas (STIC), and one (1.1%) invasive fallopian tube cancer. Subsequent cancer diagnoses included one (0.5%) primary peritoneal cancer, four (2.2%) DCIS, and seven (3.8%) invasive breast cancers. Ultimately, among all high-risk women undergoing RR surgery, about 3.3% were diagnosed with a STIC or an ovarian cancer none of which were identified on screening. All STIC and tubal cancers were diagnosed in women with BRCA mutations (6.6% rate for this group).

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Ovarian risk reducing surgery improves outcomes.

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Women with BRCA 1 mutations have a higher risk of occult tubal pathology.

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Subsequent cancers, particularly breast cancer, occur in these women.

Does virtual reality simulation have a role in training trauma and orthopaedic surgeons?

Aims

The aim of this study was to assess the current evidence relating to the benefits of virtual reality (VR) simulation in orthopaedic surgical training, and to identify areas of future research.

Materials and Methods

A literature search using the MEDLINE, Embase, and Google Scholar databases was performed. The results' titles, abstracts, and references were examined for relevance.

Results

A total of 31 articles published between 2004 and 2016 and relating to the objective validity and efficacy of specific virtual reality orthopaedic surgical simulators were identified. We found 18 studies demonstrating the construct validity of 16 different orthopaedic virtual reality simulators by comparing expert and novice performance. Eight studies have demonstrated skill acquisition on a simulator by showing improvements in performance with repeated use. A further five studies have demonstrated measurable improvements in operating theatre performance following a period of virtual reality simulator training.

Conclusion

The demonstration of 'real-world' benefits from the use of VR simulation in knee and shoulder arthroscopy is promising. However, evidence supporting its utility in other forms of orthopaedic surgery is lacking. Further studies of validity and utility should be combined with robust analyses of the cost efficiency of validated simulators to justify the financial investment required for their use in orthopaedic training. Cite this article: Bone Joint J 2018;100-B:559-65.

The role of sebum and epidermal lipids in the cosmetic properties of skin

Synopsis Lipids found in the skin are derived both from the keratinized epidermis and from the sebaceous glands. The composition of human sebum and epidermal lipids has only been fully elucidated during the past few years, and the role of these lipids is still being evaluated. This presentation reviews sebaceous gland structure and function composition of human sebum, the effects of aging and hormones on sebum secretion and the role of sebum in acne and in dry skin. In addition, a review of the role of epidermal lipids in the properties of skin includes consideration of the structure and function of the epidermis, the composition of the epidermal lipids, and the function of lipids in epidermal differentia-tion and water barrier properties. Le role du sébum et des lipides de I'épiderme dans les propriétes cosmétiques de la peau.

Nanopost plasmonic crystals

We describe a class of plasmonic crystal that consists of square arrays of nanoposts formed by soft nanoimprint lithography. As sensors, these structure show somewhat higher bulk refractive index sensitivity for aqueous solutions in the visible wavelength range as compared to plasmonic crystals consisting of square arrays of nanowells with similar dimensions, with opposite trends for the case of surface bound layers in air. Three-dimensional finite-difference time-domain simulations quantitatively capture the key features and assist in the interpretation of these and related results.

Detecting the dangerous, violent or criminal patient: an analysis of referrals to maximum security psychiatric care

Britain's high security hospitals provide care for mentally disordered patients who have dangerous, violent or criminal propensities. The State Hospital, Carstairs, takes referrals from the population of Scotland and Northern Ireland. This retrospective case-control study describes the sociodemographic and clinical characteristics of referrals (n=149) to the State Hospital during a 12-month period, and delineates differences between admitted (n=57) and rejected (n=92) patients. The referrals had an average age of 31.1 years, and were mostly male (86.6%), single (64.4%) and unemployed (90.6%). Admitted patients were more likely to have a criminal history, to be psychotic, to have a family history of mental disorder and to be viewed by the assessor as having psychotic beliefs which contributed to the behaviour or alleged offence leading to the referral. Rejected patients were more likely to have been remanded to prison or assessed by specialist registrars. Patients admitted to high security psychiatric care are more likely to show dangerous behaviour secondary to psychosis. These findings are in keeping with the requirements of mental health legislation and the admissions policy.

A phase III placebo-controlled study in advanced head and neck cancer using intratumoural cisplatin/epinephrine gel

Patients with recurrent or refractory head and neck squamous cell carcinoma received cisplatin/epinephrine injectable gel or placebo gel injected directly into the clinically dominant tumour. The double-blind phase III trial comprised of up to 6 weekly treatments over 8 weeks, 4 weekly evaluation visits, and then monthly follow-up; open-label dosing began as needed after three blinded treatments. Tumour response was defined as complete (100% regression) or partial (50-99% regression) sustained for > or =28 day, and patient benefit as attainment of palliative or preventive goals prospectively selected by investigators and patients. With cisplatin/epinephrine gel, 25% (14 out of 57) of tumours responded (16% complete regression, 9% partial regression), vs 3% (one out of 35, complete regression) with placebo (P=0.007). Patient benefit was positively associated with target tumour response in the blinded period among cisplatin/epinephrine gel recipients (P=0.024): 43% (six out of 14) of responders benefited, vs 12% (five out of 43) of non-responders. The most frequent adverse event was pain during injection and the next most frequent was local cytotoxic effects consistent with the gel's mode of action. Systemic adverse events typical of intravenous cisplatin were uncommon. Intratumoural therapy with cisplatin/epinephrine gel provided safe, well-tolerated, effective palliative treatment for patients with locally advanced head and neck squamous cell carcinoma, who lack other satisfactory treatment options.

A prognostic model for ovarian cancer

About 6000 women in the United Kingdom develop ovarian cancer each year and about two-thirds of the women will die from the disease. Establishing the prognosis of a woman with ovarian cancer is an important part of her evaluation and treatment. Prognostic models and indices in ovarian cancer should be developed using large databases and, ideally, with complete information on both prognostic indicators and long-term outcome. We developed a prognostic model using Cox regression and multiple imputation from 1189 primary cases of epithelial ovarian cancer (with median follow-up of 4.6 years). We found that the significant (P< or = 0.05) prognostic factors for overall survival were age at diagnosis, FIGO stage, grade of tumour, histology (mixed mesodermal, clear cell and endometrioid versus serous papillary), the presence or absence of ascites, albumin, alkaline phosphatase, performance status on the ZUBROD-ECOG-WHO scale, and debulking of the tumour. This model is consistent with other models in the ovarian cancer literature; it has better predictive ability and, after simplification and validation, could be used in clinical practice.

The omega-hydroxyceramides of pig epidermis are attached to corneocytes solely through omega-hydroxyl groups

The cornified outer cells of mammalian epidermis possess a monolayer of omega-hydroxyceramides that are ester-linked to the exterior of a cross-linked protein envelope. In the present study, conclusive evidence was sought on which of the ceramide hydroxyl groups are involved in the linkage to protein. This was obtained by derivatizing all free hydroxyl groups in isolated solvent-extracted porcine stratum corneum using triisopropylsilyl (TIPS) chloride in pyridine in the presence of silver nitrate. After an 18-h reaction, the tissue was recovered, rinsed, and the derivatized ceramides were then released from protein linkage by hydrolysis with 1M KOH in 95% methanol. This gave a single ceramide product that was shown by nuclear magnetic resonance to contain two triisopropyl groups. Acetylation of the product using acetic anhydride in pyridine resulted in a downfield shift of the NMR signal for the omega-methylene protons, showing that it was the omega-hydroxyl that was free in the initial reaction product, and subsequently was acetylated. These results show that all of the omega-hydroxyceramides of corneocyte lipid envelopes are attached to protein through their omega-hydroxyl groups.

A new 6-hydroxy-4-sphingenine-containing ceramide in human skin

A new ceramide consisting of 6-hydroxysphingosine linked to a non-hydroxyacid was found in human epidermal lipid. This ceramide was sought because its fatty acid and sphingoid moieties are present in other combinations in human epidermal ceramides. To isolate the new ceramide, the mixture of ceramides in human epidermal lipid was first separated into fractions by thin-layer chromatography (TLC), and then each fraction was further purified by TLC after acetylation of all hydroxyl groups. TLC after acetylation revealed that one of the fractions isolated in the first TLC step contained two components, namely, the ceramide consisting of sphingosine linked to an alpha-hydroxyacid and an unknown ceramide. The new ceramide constituted about 9% of the total ceramides, and was shown by NMR spectroscopy to be N-acyl-6-hydroxysphingosine.

X-ray diffraction analysis of isolated skin lipids: reconstitution of intercellular lipid domains

Low- and wide-angle X-ray diffraction were used to determine the structural organization of lipids isolated from the stratum corneum extracellular matrix that forms the major water permeability barrier in mammalian epidermis. Hydrated pig skin ceramides gave a single low-angle reflection of about 62 angstroms and a wide-angle-reflection at 4.15 angstroms. The addition of either cholesterol or fatty acid, the other major lipid components of the skin stratum corneum extracellular matrix, modified this diffraction pattern, depending on the lipid mole ratios. In the absence of water, lipid mixtures exhibited lipid phase separation, as shown by low- and wide-angle reflections typical of a separate cholesterol phase. However, a hydrated 2:1:1 mole ratio of ceramide:cholesterol:palmitic acid (similar to that found in stratum corneum) produced a diffraction pattern with a single sharp wide-angle reflection at 4.10 angstroms and low-angle reflections which indexed as the first eight orders of a single repeat period of 130 angstroms. The repeat period and intensity distribution of the low-angle data were similar to those found in intact stratum corneum [White et al. (1988) Biochemistry 27, 3725-3732; Bouwstra et al. (1994) Biochim. Biophys. Acta 1212, 183-192]. Higher concentrations of cholesterol or palmitic acid resulted in lipid phase separations. The 130 angstrom repeat period decreased only about 3 angstroms as water was removed by incubation in low-relative humidity atmospheres. The 130 angstrom repeat period depended on the presence of a particular ceramide, N-(omega-acyloxy)-acylsphingosine, which is found only in the epidermis. In contrast, 2:1:1 mixtures of brain ceramide:cholesterol:palmitic acid gave reflections of 56 and 34 angstroms. These results indicate that a structure with dimensions similar to those of the lamellar repeating unit found in skin stratum corneum does not depend on the presence of protein but does depend on the presence of specific skin ceramides and appropriate concentrations of cholesterol and fatty acid.

Free sphingosines of human skin include 6-hydroxysphingosine and unusually long-chain dihydrosphingosines

Ceramides containing 6-hydroxysphingosine, a previously unknown long-chain base, have recently been found in human skin. The present study investigated whether human skin also contains 6-hydroxysphingosine as the free base. Human skin surface lipids were obtained by washing with ethanol. A fraction enriched in sphingoid bases was isolated by preparative thin-layer chromatography and reacted with 2,4-dinitrofluorobenzene. The resulting N-dinitrophenyl derivatives were separated by thin-layer chromatography into three components, the most polar of which accounted for 15% of the total. After acetylation of the hydroxyl groups and repurification, each component was examined by nuclear magnetic resonance spectroscopy. The spectrum of the most polar of the derivatives indicated that it was 6-hydroxysphingosine or homologues of that substance. The spectra of the other two derivatives were virtually identical to those of derivatives prepared from authentic sphingosine and dihydrosphingosine. The chain-length distributions of the skin sphingoid bases were examined by gas chromatography after conversion of the dinitrophenyl acetates to dinitrophenyl trimethylsilyl derivatives. The analysis showed that the sphingosines and 6-hydroxysphingosines ranged from 17 to 22 carbons in length, with the 18- and 20-carbon species predominating. Surprisingly, the dihydrosphingosines included species with up to 26 carbons, with the 24-, 25-, and 26-carbon species accounting for about half of the total. Examination of the sphingoid bases of pig epidermis indicated that 6-hydroxysphingosine was not present and that the major chain length in the dihydrosphingosines was the 22-carbon species.

6-Hydroxy-4-sphingenine in human epidermal ceramides

The solvent-extractable lipids of human epidermal stratum corneum consist predominantly of ceramides. In addition two non-extractable ceramides are chemically bound to the stratum corneum protein. One of the bound ceramides, constituting 50% of the bound lipids, was previously shown to consist of very long chan omega-hydroxyacids in amide linkage with sphingosine. The second bound caramide, which forms 25% of the bound lipids, was shown to contain the same hydroxyacids, but the sphingoid base was neither sphingosine nor phytosphingosine. In the present study, the undefined bound ceramide was shown by NMR and chemical procedures to be the omega-hydroxyacid derivative of a new base, 6-hydroxy-4-sphingenine. In addition, a ceramide previously known to constitute 25% of the extractable human stratum corneum ceramides has been found to contain the same novel sphingoid base, amide-linked to long-chain alpha-hydroxyacids. Finally, a new acylceramide has been isolated and identified that consists of very long chain omega-hydroxyacids in amide linkage with the novel sphingolipid, with fatty acids esterified wit the terminal hydroxyl group of the hydroxyacid.

Adolescents in a therapeutic community: treatment implications for teen survivors of traumatic experiences

This article describes an adolescent with a history of severe traumatic experiences and treatment in a residential program for chemically dependent, severely emotionally disturbed youths between the ages of 12 and 18. It begins with a description of the long-term treatment program, the types of clients admitted, and the treatment activities provided. Basic findings from an outcome study conducted within the program made predictions regarding the length of time of residential treatment for drug addicted, severely emotionally disturbed adolescents regardless of trauma history. Pretreatment psychiatric functioning was addressed by utilizing GAF scores from the DSM-III-R for each of the participants in the study. Of 102 participants in the study, 34 were survivors of sexual abuse, physical abuse, or devastating natural disasters. A clinical case of a traumatized adolescent is presented in relation to adolescent identity, the distinction between adolescent and adult treatment, and a variety of treatment strategies that can influence an abused adolescent's long-term recovery from both addiction and trauma, including retention in treatment, the developmental stage of adolescence, identification and diagnosis of trauma during adolescence, building a working alliance, individual psychotherapy, psychopharmacology as an aid to psychotherapy, psychological debriefing, and group psychotherapy.

The relationship between tests of lung function and three chest radiological scoring systems in patients with cystic fibrosis

The chest radiographs and lung function tests of 41 patients attending the cystic fibrosis clinic at Royal Prince Alfred Hospital were reviewed. The chest radiographs were scored using three different scoring systems: the Shwachman and Kulczycki system (as modified by Doershuk), the National Institute of Health (NIH) system described by Taussig in 1973 and the Brasfield system. The scores were correlated with lung function tests. Significant correlations were found between the radiological scores and the respiratory variables; the best correlation was with the forced expiratory volume in one second (FEV1 % predicted). All three scoring systems showed a high degree of reproducibility of scores when a second radiologist was asked to score the same radiographs independently. The difference in scores between the radiologists was not significant for the NIH and the Brasfield systems. The Brasfield system is, however, the system of choice because it allows the assessment of all the major pathological features seen in cystic fibrotic chest films and consistently has the best agreement with all the lung function variables. It was also found that radiological evidence of lung hyperinflation may not be a good indicator of disease progression.

Sebaceous gland activity and serum dehydroepiandrosterone sulfate levels in boys and girls

BACKGROUND AND DESIGN

Increases in sebaceous gland activity are often the earliest sign of the approach of puberty in children. These increases have been attributed to increases in the secretion of adrenal androgens, but the supporting data are sparse and are based on measurements of urinary, rather than serum, androgen concentrations. In this study, we examined sebum composition, serum levels of dehydroepiandrosterone sulfate, and pubertal stage in 111 boys and girls, aged 2 to 15 years. Sebum composition was evaluated by measuring the ratio of wax esters/(cholesterol + cholesterol esters), a ratio known to increase with increasing sebaceous gland activity.

RESULTS

Both wax esters/(cholesterol + cholesterol esters) ratios and serum dehydroepiandrosterone sulfate levels began to increase in children 7 to 10 years old. These changes occurred in many children before the appearance of any physical signs of puberty. Wax esters/(cholesterol + cholesterol esters) ratios were correlated with dehydroepiandrosterone sulfate levels in both boys and girls. In prepubertal children, the regression lines passed through the origin. In subjects who were in early or late puberty, the y intercepts of the regression lines had positive values.

CONCLUSION

Adrenal androgens appear to be the major determinants of sebaceous gland activity during the prepubertal period and to be additive to another hormone or hormones during puberty.

Sebaceous gland lipids

Human sebum contains squalene, wax esters, triglycerides, cholesterol esters, and possibly free cholesterol. The fatty acids of the ester lipids include species with chain branching or with unusual double-bond positions. The alcohol moieties of the wax esters contain unusual chain types similar to those of the fatty acids. Genetic and hormonal factors cause individual differences in sebaceous lipid composition. Genetic factors seem to influence the proportions of the various types of branched-chain fatty acids. Androgenic stimulation of the glands causes an increase in lipid synthesis, and therefore in the ratio of endogenously synthesized lipid to exogenous lipid. Because the endogenously synthesized lipids tend to be different from lipids that are derived exogenously, the overall composition of the secretion changes. Differences in sebum composition are particularly evident when the sebum of prepubertal children is compared with that of young adults. One difference that may be of clinical significance is the different concentrations of linoleate. Higher concentrations of sebum linoleate may protect young children from comedonal acne by preventing an essential fatty acid deficiency from developing in the follicular epithelium.

A phase I and pharmacology study of GR63178A, a water-soluble analogue of mitoquidone

GR63178A is a water-soluble analogue of mitoquidone, a pentacyclic pyrroloquinone. This group of drugs exhibit a novel structure and activity against several murine solid tumours and xenografts. In the present phase I study the toxicity and pharmacokinetics of GR63178A given on 5 consecutive days of a 21-day cycle were examined. A total of 24 patients presenting with a wide range of tumours were treated at 5 doses escalated to reach the maximal tolerated dose (MTD). Linear pharmacokinetics was documented over the dose range studied, and there was no difference in parent drug handling between day 1 and day 4 of dosing. A number of metabolites were detected. The toxicity profile was unusual in that pain occurred in 20/24 patients, most often at the site of known disease. This was the dose-limiting toxicity. Other side effects included nausea and vomiting (23/24), phlebitis at the infusion site (6/24) and headache (7/24). No treatment response was seen in this study. The MTD was demonstrated to be 160 mg/m2 daily (total, 800 mg/m2 per treatment cycle). The drug has now entered phase II trials at 120 mg/m2 daily x 5, repeated every 21 days.

Cisplatinum and prednimustine, an active regimen for advanced epithelial ovarian cancer

80 patients with advanced epithelial ovarian carcinoma were treated for 6 months with cisplatinum and prednimustine following initial surgery. Response to treatment was assessed by second-look surgery. The objective response rate was 69% with 38% achieving a complete response for up to 55 months. The toxicity of this regimen was acceptable. Statistically, de-bulking or partial de-bulking had a significant beneficial effect on the likelihood of a complete response. The best survival figures were associated with maximum de-bulking. The combination of cisplatinum and prednimustine is a new and active regimen for operable advanced epithelial ovarian carcinoma.

Phase I study of the anthrapyrazole biantrazole: clinical results and pharmacology

In a phase I study the anthrapyrazole biantrazole (Warner-Lambert Company) was given to 41 patients with tumour refractory to existing therapy. The drug was given i.v. weekly for 3 weeks, with a 3-week interval between courses. At the 1st week a full pharmacokinetic study was performed, and at weeks 2 and 3, blood samples were taken at 1 and 6 h following treatment to check for drug accumulation. Biantrazole pharmacokinetics were linear with respect to the AUC (r = 0.924) over the full range of doses studied (4-36 mg/m2) but exhibited large inter-patient variations at each dose level. Elimination was triphasic, comprising two rapid early phases and a long terminal half-life (mean, 14.1 +/- 7.8 h). There was no evidence of drug accumulation over the 3-week treatment period. Approximately 12% of the parent drug was excreted unchanged in the urine together with two non-circulating, more water-soluble metabolites. Biantrazole was well tolerated but did cause moderate emesis at doses of greater than 18 mg/m2 and mild alopecia. The dose-limiting side effect was leucopenia, with no other major toxicity being observed. One patient developed biventricular failure that was not clearly related to biantrazole administration. On the present schedule, the recommended dose of biantrazole is 24 mg/m2. No response were seen in this patient population.

Unusual cholesterol esters in the sebum of young children

Cholesterol esters (CE) having fatty acids of more than 18 carbons are a prominent feature of fetal skin surface lipid (vernix caseosa), but are a minor component of adult lipid. The difference may be related to the fact that fetal sebaceous glands generally synthesize little lipid. If so, it would be expected that prepuberal children, who also have very inactive glands, would secrete CE with a large proportion of very-long-chain fatty acids. To test this conjecture, skin surface CE from young children were isolated and analyzed. Sebum was extracted from the hair of 38 children, aged six to nine. To obtain a measure of sebaceous lipogenesis, the class composition of the lipid was determined by quantitative thin-layer chromatography and the ratio of wax esters/[cholesterol + cholesterol esters] (WE/[CH + CE]) was calculated. CE were then isolated from the lipid and hydrolyzed. The freed fatty acids were converted to fatty acid methyl esters (FAME) and analyzed by capillary gas chromatography to determine the proportion with more than 18 carbons. FAME from five of the subjects were then separated into saturated and monounsaturated fractions and analyzed again by gas chromatography to identify chain types. Ratios of WE/[CH + CE] ranged from 0.08 to 2.8 in the subjects. The proportion of CE FAME with more than 18 carbons ranged from 15 to 72%, with the highest proportion being found in the children with the lowest WE/[CH + CE]. The saturated FAME were mostly iso- or anteiso-branched, whereas the monounsaturated FAME were mostly straight-chain extension products of 16: 1 delta 9 or 18: 1 delta 9.

Potentiation of cisplatin by alpha-interferon in advanced non-small cell lung cancer (NSCLC): a phase II study

Studies in experimental human lung cancer models have suggested that interferon may enhance significantly the response to some cytotoxic drugs. We have performed a phase II study of cisplatin (100 mg/m2 q.21 or 28 days) and alpha-2 interferon (3 or 5 MU three times weekly) in 68 patients with advanced non-small cell lung cancer and good performance status. As toxicity was acceptable, the dose of interferon and schedule of cisplatin were increased at the midpoint of the study. 46% (11/24) of patients with squamous carcinoma responded and an overall partial response rate of 30% was attained in 60 evaluable patients. There was no potentiation of haematological, renal or neurological toxicity but nausea and vomiting were severe. These results suggest that the combination has activity in this usually refractory disease.

Prevention of hypogammaglobulinemia of prematurity with intravenous immune globulin

We evaluated the effect of 1 g/kg intravenous immune globulin (IGIV) on immunoglobulin levels and half-life, the dose and frequency of IGIV administration necessary to maintain IgG levels at greater than 400 mg/dL, and IGIV effect on immunoglobulin levels after discharge in infants less than or equal to 32 weeks' gestation and less than or equal to 1500 g. Fifteen infants received 31 infusions at IgG levels less than or equal to 400 mg/dL. Immunoglobulin levels were obtained 24 hours postinfusion, weekly during hospitalization, and monthly after discharge. Mean IgG postinfusion was 980 mg/dL. Mean IgG half-life was 18 days (range 7 to 41). Smaller infants with greater than or equal to 5% of blood volume removed per week experienced shorter immunoglobulin half-lives. IGIV caused increased IgG levels after discharge and did not delay endogenous production of IgG. We conclude that 1 g/kg IGIV given to infants less than or equal to 32 weeks' gestation and less than or equal to 1500 g every 1 to 6 weeks during hospitalization, depending on weight and blood volume removed, prevents hypogammaglobulinemia of prematurity.

A phase II trial of mitomycin C and 5-fluorouracil as second-line therapy in advanced breast cancer

Fifty-five patients who had relapsed or progressed from chemotherapy for advanced disease were treated with mitomycin C and 5-FU on a 6 weekly regimen. After a median of 2 cycles of therapy the overall response rate was 12% with no complete responses. Significant leucopenia but no thrombocytopenia was seen and despite the low overall response rate the regimen was tolerable and did produce responses in patients primarily resistant to Adriamycin combination chemotherapy. Low overall activity indicates the need for more effective second line treatment.

Prognosis at presentation of small cell carcinoma of the lung

Prognostic factors in 411 patients with small cell lung carcinoma have been retrospectively analysed. Univariate analysis of continuous variables showed that prognosis was worse with deteriorating performance status, extensive disease, positive bone scan, increasing age, elevated total white cell count, alkaline phosphatase, lactate dehydrogenase, and decreased serum chloride and albumin. Low serum sodium was less clearly associated with poor survival. Cox multivariate regression showed that performance status, disease extent, age and raised lactate dehydrogenase and white cell count were independent prognostic factors. When disease extent was excluded from analysis, performance status, age, total white cell count, lowered serum chloride and raised lactate dehydrogenase were significant independent prognostic variables.

Changes in the relative amounts of endogenous and exogenous fatty acids in sebaceous lipids during early adolescence

Skin surface lipid samples were collected from the scalps of 40 males, aged 9-15, and the lipid class composition of each was analyzed by quantitative thin layer chromatography. The ratio of wax esters/[cholesterol + cholesterol esters] (WE/[CH + CE]) increased with age. The wax ester, cholesterol ester, triglyceride, and free fatty acid classes were isolated from each sample and the fatty acid compositions were determined by capillary gas chromatography of fatty acid methyl esters (FAME) prepared from each lipid class. The concentrations of most of the different types of fatty acids were found to be correlated with the WE/[CH + CE] ratio. Those straight chain fatty acids that are thought to be synthesized mainly within the sebaceous glands, such as 14:0, 14:1, 16:1, and 18:2 delta 5, 8 tended to increase with increasing WE/[CH + CE], while fatty acids which circulate in the blood, such as 18:0, 18:1, and 18:2 delta 9, 12, tended to decrease with increasing WE/[CH + CE]. For the majority of straight chain fatty acid types, the data could be fitted to the equation y = a + b/[x + 1], which can be derived from simple assumptions concerning the origins of the various sebum components. The FAME from the wax esters were separated into saturated and monounsaturated fractions and analyzed by capillary gas chromatography to determine the concentrations of the different types of branched chain FAME present. In the wax esters, straight chain fatty acids tended to increase with increasing WE/[CH + CE], while terminally branched (iso and anteiso) fatty acids tended to decrease. Other branched chain fatty acids increased up to a WE/[CH + CE] ratio of about 2 and then decreased at higher ratios.

The effectiveness of a cardiopulmonary resuscitation program for mothers of newborn infants

To investigate the effectiveness of a 15-minute videotape on how to perform cardiopulmonary resuscitation (CPR) on a newborn infant, 28 mothers of normal term babies completed a 12-item test on infant CPR before, immediately after, and 4-6 weeks after viewing the videotape. Statistical analysis showed that the videotape significantly improved scores on the first post-test as compared with the pre-test. At final testing, scores were significantly lower than at the first post-test, but still significantly higher than the pre-test scores. CPR education should be adopted by all institutions providing obstetrical care.

Changes in sebum secretion and the sebaceous gland

New data have shown that sebum secretion is highest in young adults and then declines steadily throughout life in both men and women. This parallels the decline in androgen levels, but this cannot be the sole factor because there is so much overlap in sebaceous gland activity between men and women. The increased occurrence of dry skin in the elderly has been shown to be unrelated to the sebum secretion rate. This is not unexpected, as children, with even less sebum, rarely have this problem. Seborrheic dermatitis, which is also much more common in the elderly, is also unrelated to sebum secretion rate.

Reduction in sudden late death by concomitant revascularization with aortic valve replacement

To determine the impact of coronary atherosclerosis and myocardial revascularization on survival after aortic valve replacement, we reviewed our experience with single aortic valve replacement between 1969 and 1984. Of 474 patients (mean age 62 +/- 13 years), 185 (39%) had no associated coronary artery disease, 233 (49%) had coronary artery bypass grafting, and 56 (12%) had unbypassed coronary artery disease. Early (30-day) mortality rates were 2.2%, 8.2%, and 7.1%, respectively (p less than 0.01, coronary disease absent versus present). Actuarial survival rates at 10 years were 77% +/- 4%, 41% +/- 6%, and 26% +/- 11% (p less than 0.001, coronary disease absent versus present), with 1 to 177 months of follow-up (mean 56 +/- 40). Preoperative angina (39%) did not predict the presence of coronary artery disease (61%). Multivariate logistic regression analysis showed that early deaths were associated with advanced preoperative New York Heart Association functional class (p less than 0.001), advanced age (p less than 0.05), more extensive coronary artery disease (p less than 0.05), and lack of cardioplegic myocardial protection (p less than 0.05). Complete revascularization did not increase operative risk when coronary artery disease was present (early mortality 6.8%, p = not significant). Late deaths were strongly associated with the presence of coronary artery disease (p less than 0.001) and reduced left ventricular ejection fraction (less than or equal to 55%, p less than 0.01). Late cardiac mortality was most commonly attributable to sudden death (30/71, 42%), especially in the unbypassed coronary disease cohort (9/14, 64%). The actuarial rate of freedom from sudden death at 10 years was 52% +/- 17% in the unbypassed coronary artery disease group (p = 0.009), compared with 90% +/- 3% and 91% +/- 3% in the revascularized and no coronary disease patients, respectively. Thus, coexistent coronary atherosclerosis has a detrimental impact on early and late survival after aortic valve replacement. Revascularization does not increase operative risk when associated coronary artery disease is present and significantly reduces the occurrence of late sudden death. Strategies that minimize operative risk when associated coronary artery disease is present include use of cardioplegia and complete revascularization.

Fatty acids of acylceramides from comedones and from the skin surface of acne patients and control subjects

Comedonal lipids and skin surface lipids were collected from six acne patients and surface lipids were collected from sex- and age-matched controls without acne. Six series of ceramides were found in each sample, the relative amounts of which were determined by thin-layer chromatography/photodensitometry. Acylceramides (ceramide 1) were isolated by preparative thin-layer chromatography and their ester-linked fatty acids were analyzed by gas-liquid chromatography. The comedonal acylceramides contained higher proportions of 16:0, 16:1 delta 6, and 18:1 delta 6 + delta 8 and much less linoleate (18:2 delta 9,12) than the acylceramides from the skin surface. In the surface lipids from legs, acylceramides from the acne patients contained less linoleate than the acylceramides from control subjects. Free fatty acids from the comedones were also isolated and analyzed, and had a composition very similar to the esterified fatty acids of comedonal acylceramides. The results confirm that fatty acids derived from sebum become incorporated into comedonal acylceramides, displacing linoleate, and show that this process even affects the acylceramides of surface epidermis, more so in acne patients than in normal subjects.

Digital dermatoglyphics in mammary cancer

Fingerprints from 200 women with histologically proven breast cancer (case group) were compared to fingerprints from 138 women with no history of any malignant disease (control group). Of the patterns analyzed, four were significantly associated with breast cancer: accidentals, transitionals, angled ulnar loops, and horizontal ulnar loops. A fifth print, the angled radial loop, was found to be of borderline importance as an independent predictor of breast cancer. Of 200 patients in the case group, 27 had one or more accidental prints, 58 had one or more transitionals, 34 had one or more horizontal ulnar loops, and 93 had one or more angled ulnar loop patterns. In 138 control subjects there were 2 with accidental patterns, 21 with one or more transitionals, 6 with horizontal ulnar loops, and 16 with one or more angled ulnar loops. In addition, there appeared to be a gradient of risk; a woman with one type of suspicious print is at higher risk of breast cancer than a woman with none, and two suspicious prints indicate a higher risk than does one. If these findings are confirmed, the prints described will represent a noninvasive anatomical marker of breast cancer risk.

The effect of 13-cis-retinoic acid on sebaceous glands

The drug, 13-cis-retinoic acid, which has been demonstrated to have a marked effect on nodulocystic acne, probably has several mechanisms of action. This article summarizes the effects on the sebaceous glands, and the accompanying changes in cutaneous lipids that result from 13-cis-retinoic acid therapy. These changes in lipid composition support the concept that linoleate may be of importance in the pathogenesis of acne.

The St. Jude valve: analysis of thromboembolism, warfarin-related hemorrhage, and survival

From March 1978-86, 590 St. Jude prostheses (232 aortic, 232 mitral, and 63 double aortic-mitral) were implanted in 527 patients (mean age 63 years) and followed for up to 8 years (mean 33 months; three lost; 99% complete). The early (30-day) mortality rate was 8.9% and was strongly associated with preoperatively depressed left ventricular function (ejection fraction less than 0.55), ischemic mitral regurgitation, and advanced functional class (IV) (p less than 0.05). Actuarial survival rates at 5 years were 72% +/- 4%, 72% +/- 8%, and 63 +/- 4% after aortic, double, and mitral valve replacement (p less than 0.01). There have been no structural failures. Embolism (28 events, 2.1%/patient-year) was less common with warfarin treatment (1.5%/patient-year; n = 492) than with antiplatelet (3.2%/patient-year; n = 19) or no drug therapy (18.9%/patient-year; n = 16) (p less than 0.01). One embolic event was fatal (3.6%). Warfarin-treated patients remained 91% +/- 1% free of emboli after 8 years. Valve thrombosis (six events; 0.4%/patient-year) occurred exclusively in patients not treated with effective warfarin therapy; one (17%) died. The most common complication was hemorrhage (39 events; 2.9%/patient-year); nine (23%) were fatal, and these constituted 82% of 11 valve-related late deaths. In warfarin-treated patients (target prothrombin time ratio 1.5 to 2.5), hemorrhage was twice as frequent (2.9%/patient-year) as embolism (1.5%/patient-year).(ABSTRACT TRUNCATED AT 250 WORDS)

Maternally administered antenatal vitamin K1: effect on neonatal prothrombin activity, partial thromboplastin time, and intraventricular hemorrhage

Infants weighing 1500 g or less at birth are susceptible to intraventricular hemorrhage. This may be due in part to low concentrations of vitamin K-dependent clotting factors. Women in labor between 24-34 weeks' gestation were selected, according to their hospital registration number, to receive 10 mg vitamin K1 intramuscularly at least four hours before delivery. Control women received no vitamin K. The study included only infants born of mothers who were in hospital more than four hours before delivery, who weighed 1500 g or less at birth, and were less than 34 weeks' gestation. Twenty vitamin K1 and 33 control infants qualified for the study. Infants in both groups received routine postnatal vitamin K1. On admission, the infant's prothrombin activity and partial thromboplastin time (PTT) were measured. A head ultrasound was done between days 2 and 4 of life. Results demonstrated significantly improved prothrombin activity, a nonsignificant trend toward improved PTT, and a significantly decreased frequency of intraventricular hemorrhage in infants whose mothers had received vitamin K1. The effect of antenatal vitamin K1 on prothrombin activity and PTT appeared to be more pronounced in female infants.

Evaluation of a method for measuring the sustainable rate of sebaceous wax ester secretion

Sebaceous wax ester secretion rates were measured in six subjects on six occasions each, using absorption into bentonite clay and analysis of the collected lipid by quantitative thin-layer chromatography. On each occasion eight samples were collected, four from the left and four from the right side of the forehead in four successive intervals. The first two intervals, which totaled 14 h, were intended to deplete the follicular reservoir of sebum so that a constant rate of absorption could be obtained during the third and fourth intervals, which were 3 h each. Thin-layer analysis of each sample was done in triplicate. The data were examined using analysis of variance techniques to determine the reproducibility of the measurement method and to identify possible sources of variability. The intraclass correlation coefficient (rI) for all 432 post-depletion determinations was 0.80. The reproducibility was considerably better for three of the subjects (rI = 0.93) than for the other three (rI = 0.75). Variability within the latter three subjects did not seem to be attributable to lack of reproducibility in the thin-layer analysis. Real biological variability also seems unlikely considering the holocrine mechanism of sebum secretion. Therefore, the variability probably arises from non-representative collection of sebum into the bentonite absorbent.

Treatment of severe platelet dysfunction and hemorrhage after cardiopulmonary bypass: reduction in blood product usage with desmopressin

Impairment of platelet function commonly occurs after cardiopulmonary bypass, and may result in substantial bleeding. Because desmopressin acetate (a synthetic analogue of vasopressin) shortens bleeding time in a variety of platelet disorders, a controlled clinical trial of intravenous desmopressin was performed in 39 patients with excessive mediastinal bleeding (greater than 100 ml/h) and a prolonged template bleeding time (greater than 10 minutes) more than 2 hours after termination of cardiopulmonary bypass. Twenty-three desmopressin recipients and 16 control patients (no desmopressin) were similar in surgical procedure, pump time, platelet count, template bleeding time and amount of bleeding before therapy (p = NS). Compared with the control group, the patients receiving desmopressin (20 micrograms; mean 0.3 micrograms/kg) utilized fewer blood products (29 +/- 19 versus 15 +/- 13 units/patient; p less than 0.05), especially platelets (12 +/- 9 versus 4 +/- 7 units/patient; p = 0.004), while achieving a similarly effective reduction in mediastinal bleeding (4.8- and 4.3-fold, p = 0.001 for both). Severe platelet dysfunction was partially corrected within 1 hour after desmopressin infusion, during which interval no blood products were administered: the template bleeding time shortened (from 17 to 12.5 minutes, p less than 0.05), whereas the platelet count remained unchanged (at 96 +/- 35 and 105 +/- 31 X 10(3)/mm3, p = NS). The plasma levels of two factor VIII components increased: procoagulant activity (VIII:C) from 0.97 +/- 0.43 to 1.52 +/- 0.74 units/ml (p less than 0.05) and von Willebrand factor (VIII:vWF) from 1.28 to 1.78 units/ml (p less than 0.05); these increases correlated with the shortening of the bleeding time (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental evaluation of technetium-99m red blood cell radionuclide ventriculography for detecting pericardial bleeding

Abnormal loculated or diffuse blood pools adjacent to the heart have been observed in patients with pericardial bleeding who have been imaged by gated equilibrium radionuclide ventriculography (RNV). To study the scintigraphic appearance of fresh pericardial blood, we performed equilibrium RNV in six dogs with measured volumes (10, 30, or 50 ml) of intrapericardial blood. Loculated and diffuse pericardial blood was simulated by injecting the blood either into an intrapericardial balloon, or freely into the pericardial space. Ability to detect pericardial blood was determined by blinded review, and blood volume analysis was attempted by measuring its scintigraphic thickness, brightness (relative to the left ventricle), extent, and background-subtracted count rate and a peak count index. Detection rates for 10, 30, and 50 ml were all 100% for loculated pericardial blood, and 67%, 100% and 100% for free pericardial blood, with the use of three scintigraphic views. Visually determined "extent" of the abnormal blood pool was the most reliable indicator of pericardial blood volume. When the volume was 30 ml or more, at least 40% of the heart was surrounded in 26 of 27 cases (96%); the specificity of this finding was 90%. We conclude from this animal study that RNV should be a sensitive method for detecting pericardial bleeding; visual appearance permits qualitative assessment of the volume of accumulated labeled blood.

Skin lipids: an update

The stratum corneum lipids, responsible for the epidermal water barrier, consist principally of ceramides, cholesterol, cholesteryl sulfate, and free fatty acids. These lipids are arranged in multiple intercellular lamellae that provide an efficient water barrier because of the crystalline array of the straight and predominantly saturated lipid chains. Interlamellar linkages provided by lipids based on 30-carbon omega-hydroxyacids may be responsible for holding together the intercellular lamellae as well as for assembly of the lamellar granules of the granular cells. The normally ordered exfoliation of corneocytes as they arrive at the surface seems to require hydrolysis of the cholesteryl sulfate to free cholesterol. The sebaceous glands secrete continuously, producing sebum that consists predominantly of triglycerides, wax esters, and squalene. High rates of sebum production per sebocyte result in low levels of linoleate in the sebaceous esters, subjecting the follicular epithelium to essential fatty acid deficiency and the characteristic hyperkeratosis that results in comedo formation. Suppression of sebum production by drugs elevates sebum linoleate concentration and relieves follicular hyperkeratosis. Thus, sebum continues to be a prime suspect in the crime of acne. Low levels of sebaceous gland activity are not correlated with the occurrence of dry skin.

Skin surface lipids of the mole Scalopus aquaticus

Skin surface lipids of the mole Scalopus aquaticus were found to consist principally of squalene (70%), wax esters (15%), and sterol esters (5%), together with small amounts of triglycerides, free fatty acids, free fatty alcohols, and free sterols. Analysis of the fatty acids occurring free and as wax esters and sterol esters showed these to consist of approximately equal amounts of saturated and monounsaturated compounds. The saturated fatty acids consisted predominantly of odd-carbon anteiso and even-carbon straight-chain compounds, with minor amounts of even-carbon iso-branched chains. The unsaturated fatty acids had double bond positions that would have been produced by delta 9-desaturation of C14, C16 and C18 straight chain saturated precursors. Both the free and the esterified fatty alcohols had chain structures corresponding with those of the fatty acids but of somewhat greater average chain length. Discovery of a major proportion of squalene in the sebum of this animal extends the number of non-human species that have this characteristic to four, all of which inhabit a damp environment, suggesting that squalene conveys some biological advantage under these conditions.

Dilutional effect of increased sebaceous gland activity on the proportion of linoleic acid in sebaceous wax esters and in epidermal acylceramides

Sebaceous wax esters and epidermal acylceramides were isolated from skin surface lipid obtained from children and from young adults. Fatty acid methyl esters (FAME) were prepared from the esterified fatty acids of these lipid classes and analyzed to ascertain the proportions of methyl linoleate (18:2 delta 9,12), methyl sebaleate (18:2 delta 5,8), and methyl sapienate (16:1 delta 6). On the same subjects, 2 measures of sebum secretion rate were obtained, namely the sustainable wax ester secretion rate (WESR) on the forehead and the ratio of wax esters/(cholesterol + cholesterol esters) [WE/(CH + CE)] in the surface lipid. The proportions of methyl linoleate in FAME from the wax esters decreased, and the proportions of methyl sebaleate increased, with increased rates of sebum secretion. For both methyl linoleate and methyl sebaleate, a better correlation was obtained when the ratio of WE/(CH + CE) was used as a measure of sebum secretion rather than the WESR. The proportions of methyl linoleate in the FAME from the acylceramides were also inversely related to ratios of WE/(CH + CE). In acylceramides, linoleate was replaced by sapienate, a major fatty acid of human sebum. It appears, therefore, that sebum fatty acid composition may change with changes in sebaceous gland activity, and that sebum fatty acids can enter the epidermis and be incorporated into epidermal lipids.

Effect of cyproterone acetate-ethinyl estradiol treatment on the proportions of linoleic and sebaleic acids in various skin surface lipid classes

The effect of high-dose cyproterone acetate-ethinyl estradiol treatment on rates of sebum secretion and on the proportions of linoleic acid (18:2 delta 9,12) and sebaleic acid (18:2 delta 5,8) in the skin surface lipids of three female acne patients was examined. Changes in rates of sebum secretion were evaluated indirectly by measuring the ratio of wax esters/(cholesterol + cholesterol esters) in the subjects' skin surface lipid. In two of the subjects, this ratio indicated a reduction of sebum secretion rates to the childhood range. Concomitantly, there was an increase in linoleic acid and a decrease in sebaleic acid in all lipid classes. In the third subject, in whom there was only a small reduction in sebum secretion rate, the proportion of linoleic acid in the cholesterol esters more than doubled, but the changes in the other lipid classes were small or nonexistent. The results indicate that the proportions of linoleic acid and sebaleic acid in sebum are influenced by sebum secretion rates.

Changes in sebum secretion and the sebaceous gland

New data have shown that sebum secretion is highest in young adults and then declines steadily throughout life in both men and women. This parallels the decline in androgen levels, but this cannot be the sole factor because there is so much overlap in sebaceous gland activity between men and women. The increased occurrence of dry skin in the elderly has been shown to be unrelated to the sebum secretion rate. This is not unexpected, as children, with even less sebum, rarely have this problem. Seborrheic dermatitis, which is also much more common in the elderly, is also unrelated to sebum secretion rate.

Possible genetic control of the proportions of branched-chain fatty acids in human sebaceous wax esters

The composition of human sebum varies among individuals with respect to the proportions of various types of fatty acids in the ester lipid classes. Iso-branched fatty acids with even numbers of carbons (iso-even) are particularly variable. However, in 13 identical twin pairs, intrapair differences in the proportions of iso-even fatty acids in sebaceous wax esters were found to be very small, while interpair differences were as large as in the nontwin population. Intrapair differences in iso-even fatty acids were also quite small in 4 of 8 fraternal twin pairs. Heritability estimates suggested that proportions of iso-even fatty acids in human sebum are controlled, at least in part, by genotype.

Essential fatty acids and acne

Acne is characterized by hyperkeratosis of the follicular epithelium, leading to horny impactions that may lie dormant as open or closed comedones or may cause inflammation of the follicle. Although persons with acne have consistently been observed to have elevated levels of sebum secretion, no mechanism relating sebum secretion rates to comedogenesis is known. Acne patients have also been shown to have low levels of linoleic acid in their skin surface lipids. To explain this observation, the hypothesis is advanced that the linoleate concentration in human sebum depends on the quantity of linoleic acid present in each sebaceous cell at the commencement of its differentiation and on the extent to which this initial charge is diluted by subsequent endogenous lipid synthesis in each sebaceous cell. A corollary hypothesis holds that low concentrations of linoleate in sebum impose a state of essential fatty acid deficiency on the cells of the follicular epithelium and induce the characteristic response of hyperkeratosis. Both hypotheses could hold, without there being a systemic deficiency of linoleic acid, simply as the result of elevated lipogenesis in individual sebaceous cells.

Effects of dietary selenium and vitamin E on plasma lipoprotein cholesterol levels in male rats

Male Fischer-344 rats fed a diet deficient in both vitamin E and selenium (Se) for 20 weeks had higher levels of low-density lipoprotein cholesterol than age-matched rats fed an identical diet but supplemented with these micronutrients. The rats supplemented with both vitamin E and Se were switched to a diet deficient in both these micronutrients at week 20. These rats eventually developed elevated levels of low-density lipoprotein cholesterol compared to age-matched rats either continuously maintained on the diet supplemented with vitamin E and Se or rats switched (at week 20) from the vitamin E-and Se-deficient diet to a diet supplemented with both these micronutrients. In a second experiment, we found that Se deficiency alone was sufficient to significantly elevate low-density lipoprotein cholesterol. The basal diet used in these experiments had a very low cholesterol content and the observed alterations in lipoprotein cholesterol levels are likely to reflect alterations in the metabolism of endogenously synthesized cholesterol.

Age-related changes in sebaceous wax ester secretion rates in men and women

Sustainable rates of sebaceous wax ester secretion were measured on the foreheads of 109 men and 167 women, aged 15-97. Each measurement was made after first depleting the cutaneous sebum reservoir by overnight absorption of lipid into a layer of bentonite clay. Lipid was then absorbed for 3 h into fresh clay in which two 2-cm cloth disks were embedded. The absorbed lipid was extracted from the disks with ether and analyzed for wax esters by thin-layer chromatography. For both men and women there was a wide range of wax ester secretion rates at all ages. Rates were highest in the 15- to 35-year-olds and appeared to decline continuously throughout the adult age range. Values of log(wax esters) were better correlated with age than the untransformed values of wax ester secretion. The equations of best fit of log(wax esters) vs age suggested that sebum secretion declines about 23% per decade in men and 32% per decade in women.

Proportions of various straight and branched fatty acid chain types in the sebaceous wax esters of young children

The fatty acid composition of sebaceous wax esters was examined in 20 children, ages 6-8, using quartz capillary gas chromatography. The results were compared with a previously reported study of wax ester composition in 10 adults, in which the same analytical techniques were used. The children's wax esters showed more variability in the proportions of all fatty acid chain types than was found in adults. The most striking difference between the 2 age groups was in the proportions of iso-branched fatty acids with odd numbers of carbon atoms. These ranged from 1-26% of fatty acids in the children's wax esters but were not more than 3% of fatty acids in the adults' wax esters. Some of the variability in wax ester fatty acid composition in children seemed to be related to variation in rates of sebum production. The highest percentages of terminally branched (iso-even, iso-odd, and anteiso) and the lowest percentages of internally branched fatty acids were found in the children with the lowest rates of sebum secretion. However, even in children with similar rates of sebum secretion there were considerable differences in wax ester fatty acid composition, especially with respect to iso-even fatty acids. The results suggest that sebum fatty acid composition is influenced both by genetic factors and by limitations on the supply of precursors for terminally branched, but not internally branched, fatty acids.