Enzymatically-controlled biomimetic synthesis of titania/protein hybrid thin films.

Although it is widely recognised that enzymes play a significant role in sculpting complex silica skeletons in marine sponges, the potential for exploiting enzymes in materials synthesis has not yet been fully harnessed. In this work we show that the digestive enzyme papain can self-assemble into monolayers on oxide surfaces, where they then drive the formation of crystalline titanium dioxide nanoparticles. This dual functionality of thin film formation and mineralization promotion has the potential to enable the construction of hierarchical inorganic/organic structures in the form of continuous amorphous titania/protein films which can be refined to 93% anatase post annealing. Additional control over the film thickness is afforded by layer-by-layer processing using a simple dip-coating approach. Papain's TiO2-mineralizing activity displays complex kinetics that deviates from the native Michaelis-Menten kinetic activity, yet deactivation studies demonstrate that this activity relies upon residues that are essential for catalytic site function. These parameters provide unique insight into enzymatic biomineralization, allowing a flexible route to achieving bioengineered titania heterostructures, and potentially providing a green-chemistry solution to photovoltaic cell development.

Meta-analysis of studies using selective alpha1-blockers in patients with hypertension and type 2 diabetes.

This meta-analysis of published studies evaluated the effect of selective alpha1-blockers on lipid and carbohydrate profiles and blood pressure (BP) as well as tolerability in patients with hypertension and type 2 diabetes. Publications identified via MEDLINE were used. Text and bibliographies of retrieved articles were examined for additional references. Clinical trials with a randomised comparative structure (placebo and active treatment arms) and controlled studies with other structures were included. Of the 27 citations identified, 22 studies were selected for inclusion, and five were rejected. Efficacy and safety data, lipid and carbohydrate profiles, and study and patient characteristics were extracted by two investigators independently. The mean pooled results showed beneficial effects of selective alpha1-blockers on total serum cholesterol (TC), high-density lipoprotein (HDL) cholesterol, and systolic and diastolic BP. The results also showed doxazosin had beneficial effects on fasting glucose levels, insulin sensitivity, TC, HDL cholesterol, low-density lipoprotein (LDL) cholesterol, HDL/TC ratio, and systolic and diastolic BP. The risk difference was equivalent between the alpha1-blocker group and the control group for postural hypotension or syncope. This meta-analysis demonstrates a number of favourable effects of therapy with selective alpha1-blockers in hypertensive patients with type 2 diabetes. These agents provide an effective modality for reducing BP, with favourable effects on lipid, no deterioration in glycaemic control, and little risk of orthostatic hypotension.

ACF consists of two subunits, Acf1 and ISWI, that function cooperatively in the ATP-dependent catalysis of chromatin assembly.

The assembly of core histones and DNA into periodic nucleosome arrays is mediated by ACF, an ISWI-containing factor, and NAP-1, a core histone chaperone, in an ATP-dependent process. We describe the isolation of Drosophila acf1 cDNA, which encodes the p170 and p185 forms of the Acf1 protein in ACF. Acf1 is a novel protein that contains two PHD fingers, one bromodomain, and two new conserved regions. Human WSTF, which is encoded by one of multiple genes that is deleted in Williams syndrome individuals, is the only currently known mammalian protein with each of the conserved motifs in Acf1. Purification of the native form of Acf1 led to the isolation of ACF comprising Acf1 (both p170 and p185 forms) and ISWI. Native Acf1 did not copurify with components of NURF or CHRAC, which are other ISWI-containing complexes in Drosophila. Purified recombinant ACF, consisting of Acf1 (either p185 alone or both p170 and p185) and ISWI, catalyzes the deposition of histones into extended periodic nucleosome arrays. Notably, the Acf1 and ISWI subunits function synergistically in the assembly of chromatin. ISWI alone exhibits a weak activity that is approximately 3% that of ACF. These results indicate that both Acf1 and ISWI participate in the chromatin assembly process and suggest further that the Acf1 subunit confers additional functionality to the general 'motor' activity of ISWI.

SZF1: a novel KRAB-zinc finger gene expressed in CD34+ stem/progenitor cells.

The identification and study of genes expressed in hematopoietic stem/progenitor cells should further our understanding of hematopoiesis. Transcription factors in particular are likely to play important roles in maintaining the set of genes that define the stem/progenitor cell. We report here the identification of a putative KRAB-zinc finger gene (SZF1) from a cDNA library prepared from human bone marrow CD34+ cells. Characterization of SZF1 implicates its role in hematopoiesis. The predicted protein contains a highly conserved KRAB domain at the NH2 terminus and four zinc fingers of the C2H2 type at the COOH terminus. Two alternatively spliced products of SZF1 were isolated, which predict proteins of 421 (SZF1-1) and 361 (SZF1-2) amino acids, differing from each other only at the carboxy terminus. The two transcripts of SZF1 have different expression patterns. SZF1-2 is ubiquitously expressed, as indicated by Northern blot, RNase protection, and reverse transcriptase polymerase chain reaction. SZF1-1 expression, in contrast, was detected only in CD34+ cells. We recently isolated the promoter region for the stem/progenitor cell expressed FLT3/FLK-2/STK-1 gene and used this region to generate a reporter construct to test the effect of SZF1 expression. Cotransfection of the reporter construct with SZF1 constructs showed that SZF1-2 repressed transcription three- to fourfold, whereas SZF1-1 showed a lower level of repression. The expression pattern of SZF1 transcripts and the transcriptional repression of a CD34+-specific promoter demonstrate a possible role for SZF1 in hematopoietic stem/progenitor cell differentiation.

Safety of long-acting dihydropyridine calcium channel blockers in hypertensive patients.

Issues raised recently concerning the safety of calcium channel blockers (CCBs) prompted an analysis of the occurrence of cardiovascular events and death in the Pfizer Inc. hypertension clinical trial databases for amlodipine (Norvasc) and nifedipine in the gastrointestinal therapeutic system (GITS) formulation (Procardia XL). Prospectively defined analyses of data from comparative and noncomparative trials of amlodipine and nifedipine GITS were conducted. Outcome measures included cardiovascular and noncardiovascular deaths, and adverse cardiovascular events including new/worsened angina, myocardial infarction (MI), serious arrhythmia, stroke, congestive heart failure, and bleeding. Among all amlodipine-treated patients (n = 32,920), the incidence rates for all-cause death, MI, and new/worsened angina were 3.0, 3.3, and 1.6/1,000 patient-years of exposure, respectively. Among those in comparative trials alone (n = 4,126), the all-cause death rate was 4.1/1,000 patient-years, which was comparable to that of other non-CCB agents and significantly less than that of other CCBs (23.8/1,000 patient-years, p = 0.015), although the difference in rates represents only 2 deaths. Among all nifedipine-GITS-treated patients (n = 2,645), the rate of all-cause death was 4.1/1,000 patient-years, of MI 6.5/1,000 patient-years, and of new/ worsened angina 5.7/1,000 patient-years. The incidence rates for MI and other cardiac events were low in these hypertension trials, and did not differ among treatment groups in either the amlodipine or nifedipine GITS comparative analyses. In the clinical trial databases analyzed, there is no signal suggesting excessive risk of death or cardiovascular events for hypertensive patients treated with amlodipine or nifedipine GITS.

Effects of doxazosin in patients with mild, intermediate, and severe benign prostatic hyperplasia.

Traditionally, drug therapy for benign prostatic hyperplasia (BPH) has been reserved for patients with mild or moderate symptoms. The objective of this analysis was to compare responses to an alpha 1-adrenergic receptor blocker, doxazosin, in patients with severe, intermediate, and mild disease. Data were analyzed from patients with symptomatic BPH who were enrolled in two 16-week, double-masked, placebo-controlled studies of doxazosin. In study 1, 163 hypertensive patients were stratified according to baseline maximum (Qmax) and mean (Qmean) urinary flow rate as having severe, intermediate, or mild disease. In study 2, 82 normotensive patients were stratified according to their baseline American Urological Association (AUA) BPH symptom severity score and modified Boyarsky symptom bothersomeness score. Overall, doxazosin was significantly more effective than placebo in improving Qmax and Qmean in study 1 and in improving the AUA-derived and modified Boyarsky scores in study 2. There were statistically significant differences in the response to treatment, as represented by Qmax' Qmean, and modified Boyarsky score, between patients with severe, intermediate, and mild disease. There were no significant differences in the AUA-derived scores of patients in the three severity groups. These results have important clinical implications, suggesting that the majority of BPH patients are candidates for a course of drug therapy, regardless of baseline disease status.

Oropharyngeal candidiasis in patients with AIDS: randomized comparison of fluconazole versus nystatin oral suspensions.

A total of 167 human immunodeficiency virus (HIV)-infected patients with oropharyngeal candidiasis were randomly assigned to receive 14 days of therapy with liquid suspension fluconazole (100 mg once daily) or liquid nystatin (500,000 U four times daily). At day 14, 87% of the fluconazole-treated patients were clinically cured, as opposed to 52% in the nystatin-treated group (P < .001). Fluconazole eradicated Candida organisms from the oral flora in 60%, vs. a 6% eradication rate with nystatin (P < .001). The fluconazole group had fewer relapses noted on day 28 (18%, vs. 44% in the nystatin group; P < .001). This relapse difference no longer existed by day 42. Fluconazole oral suspension as a systemic therapy was more effective than liquid nystatin as a topical therapy in the treatment of oral candidiasis in HIV-infected patients and provided a longer disease-free interval before relapse.

JAK3: expression and mapping to chromosome 19p12-13.1.

We cloned JAK3, the most recently described member of the JAK family of intracellular tyrosine kinases, from normal human CD34+ RNA. JAK3 is involved in the signal transduction pathways of the IL-2, IL-4, IL7, IL-9, and IL-15 receptors by association with their common gamma-chain (gamma[c]). JAK3 is critical to lymphoid development, as recently established by the linking of mutations in JAK3 to a subgroup of patients with SCID and the generation of JAK3-null mice with severe disruptions in normal lymphocytic development. However, JAK3 expression is not restricted to the lymphocytic compartment of bone marrow but is found in a wide range of tissues of both hematopoietic and non-hematopoietic origin. Northern blot analysis indicates that JAK3 is also expressed in adult placenta, lung, liver, kidney, pancreas, spleen, thymus, ovary, and small intestine. RNAse protection assays and RT-PCR indicate that JAK3 is expressed in a variety of leukemic-derived hematopoietic cell lines with myeloid and/or lymphoid phenotypes. In normal human bone marrow, JAK3 is expressed in the CD34+/lineage- fraction, which is highly enriched in hematopoietic stem/progenitor cells. In addition, we found a splice variant of JAK3 which is formed by the splicing of JAK3 with exon II of the leydig insulin-like (LEY I-L) hormone. RT-PCR and RNAse protection assay analyses indicate that this variant (termed I-JAK3) is normally expressed in almost all hematopoietic and non-hematopoietic tissues shown to express JAK3. Using fluorescence in situ hybridization we have localized JAK3 to 19p12-13.1, the same region of chromosome 19 to which the LEY I-L hormone maps (19p12-13.2).

Principal results of the Hypertension and Lipid Trial (HALT): a multicenter study of doxazosin in patients with hypertension.

The Hypertension and Lipid Trial (HALT) was undertaken to assess the efficacy and safety of doxazosin, a selective alpha 1- adrenergic blocker, in patients with hypertension in a clinical practice setting. The effects of doxazosin on office blood pressure, changes in lipid profiles, and theoretic coronary disease risk were studied. In an open, noncomparative, multicenter trial, 851 patients were studied for a maximum of 16 weeks. Doxazosin significantly reduced mean sitting systolic blood pressure (SBP) and diastolic blood pressure (DBP) by 15.2/12.5 mm Hg and standing SBP and DBP by 16.1/12.7 mm Hg in the total study population (n = 807; p = 0.0001), with no significant effect on heart rate. Mean total cholesterol levels were significantly reduced by 2.7%, low-density lipoprotein cholesterol levels by 2.4%, and mean triglyceride levels by 3.4% (all p values < 0.05). High-density lipoprotein (HDL) cholesterol levels were essentially unchanged. The mean ratio of total to HDL cholesterol was significantly reduced (p < 0.05). Mean predicted 5-year coronary disease risk was significantly reduced with doxazosin therapy by 14.7% in previously untreated patients (p < 0.0001) and by 1.7% in patients who were previously receiving antihypertensive therapy (p < 0.05). The drug was well tolerated. This study demonstrates that antihypertensive therapy with doxazosin can favorably affect coronary disease risk factors and reduce predicted coronary disease risk.

Expression of the hematopoietic growth factor receptor FLT3 (STK-1/Flk2) in human leukemias.

Normal expression of the hematopoietic growth factor receptor FLT3 (STK-1@Flk2) is limited to CD34+ stem/progenitor cells. We have evaluated the expression of FLT3 by RNase protection assay and Western blotting in 161 primary bone marrow (BM) samples from patients with leukemia. FLT3 RNA was found to be expressed at a higher level than in normal BM controls in 33 of 33 B-lineage acute leukemias, 11 of 12 acute myeloid leukemias (AMLs), and 3 of 11 T-cell acute leukemias (T-ALLs). Expression of FLT3 RNA was also observed in some cases of blast crisis CML. The FLT3 signal resulted from expression on the leukemic blasts, and was not caused by increased FLT3 expression on normal CD34+ stem/progenitor cells in the leukemic samples. To determine if FLT3 protein was also overexpressed, proteins were extracted from leukemic BM samples and screened by Western blotting with anti-FLT3 antisera. FLT3 protein was not detected in normal BM controls, but was found in 14 of 14 B-lineage ALLs, 36 of 41 AMLs, and 1 of 4 T-ALLs. Stimulation of patient samples with FLT3 ligand resulted in autophosphorylation of the FLT3 receptor, suggesting the receptor is functional in these cells. These data show that FLT3 RNA and protein are aberrantly expressed by AML and ALL cells in that CD34 expression and FLT3 expression are no longer synchronous, and suggest the possibility that overexpression of FLT3 could play a role in the survival and/or proliferation of malignant clones in acute myeloid and lymphoid leukemias.

Efficacy and safety of fluconazole prophylaxis for fungal infections after marrow transplantation--a prospective, randomized, double-blind study.

A randomized, double-blind, placebo-controlled trial assessed the efficacy and toxicity of 400 mg/day fluconazole in preventing fungal infections during the first 75 days after marrow transplantation. During prophylaxis, systemic fungal infections occurred in 10 (7%) of 152 fluconazole-treated patients compared with 26 (18%) of 148 placebo-treated patients (P = .004). There were no Candida albicans infections in fluconazole recipients compared with 18 in placebo recipients (P < .001) and no significant increase in Candida infections other than C. albicans. Fluconazole also significantly reduced the incidence of superficial fungal infections (P < .001), fungal colonization (P = .037), and empiric amphotericin B use (P = .005). The probability of survival was improved in fluconazole recipients, in whom 31 deaths occurred up to day 110 after transplantation compared with 52 deaths in placebo recipients (P = .004). No clinically significant toxicity was detected with fluconazole use. Prophylactic fluconazole was safe and significantly reduced systemic fungal infections with other benefits, including improved survival at day 110 after marrow transplantation.

Nighttime dosing of doxazosin has peak effect on morning ambulatory blood pressure. Results of the HALT Study. Hypertension and Lipid Trial Study Group.

In this study the effects of a single daily dose (average 8.9 mg) of doxazosin (an alpha-adrenergic blocker) given at night were evaluated in 111 patients with mild hypertension. Patients were studied first on no medication, and a second time after being treated for up to 16 weeks with doxazosin. Blood pressure was measured by noninvasive ambulatory monitoring at the beginning and end of the study. There was a sustained reduction of both systolic and diastolic pressure throughout the day and night, but the greatest reduction occurred in the morning hours. Since the peak treatment effect was later than predicted from previous pharmacokinetic studies, it is suggested that the timing of the peak effect may depend on the prevailing level of alpha-adrenergic tone, as well as on the pharmacokinetics of the drug.

Differential effects of doxazosin on clinic and ambulatory pressure according to age, gender, and presence of white coat hypertension. Results of the HALT Study. Hypertension and Lipid Trial Study Group.

In this study the effects of a single daily dose of doxazosin (an alpha-adrenergic blocker) given at night were evaluated in 112 patients with mild hypertension. Patients were studied first on no medication, and a second time after being treated for up to 16 weeks with doxazosin. Blood pressure (BP) was measured by noninvasive ambulatory monitoring at the beginning and end of the study. Before treatment, the white coat effect (clinic-ambulatory BP) was greater in women than in men (significant for systolic pressure but not diastolic), and greater in elderly (aged over 65 years) than in younger patients (significant for both systolic and diastolic pressure). Clinic and ambulatory BP were reduced to a similar extent in men and women by doxazosin, but in the elderly the fall in clinic BP was associated with a much smaller fall of ambulatory BP. In patients with white coat hypertension (elevated clinic but normal ambulatory BP) doxazosin lowered clinic but not ambulatory BP, while in those with sustained hypertension it lowered both.

STK-1, the human homolog of Flk-2/Flt-3, is selectively expressed in CD34+ human bone marrow cells and is involved in the proliferation of early progenitor/stem cells.

We cloned the cDNA for stem cell tyrosine kinase 1 (STK-1), the human homolog of murine Flk-2/Flt-3, from a CD34+ hematopoietic stem cell-enriched library and investigated its expression in subsets of normal human bone marrow. The cDNA encodes a protein of 993 aa with 85% identity and 92% similarity to Flk-2/Flt-3. STK-1 is a member of the type III receptor tyrosine kinase family that includes KIT (steel factor receptor), FMS (colony-stimulating factor 1R), and platelet-derived growth factor receptor. STK-1 expression in human blood and marrow is restricted to CD34+ cells, a population greatly enriched for stem/progenitor cells. Anti-STK-1 antiserum recognizes polypeptides of 160 and 130 kDa in several STK-1-expressing cell lines and in 3T3 cells transfected with a STK-1 expression vector. Antisense oligonucleotides directed against STK-1 sequences inhibited hematopoietic colony formation, most strongly in long-term bone marrow cultures. These data suggest that STK-1 may function as a growth factor receptor on hematopoietic stem and/or progenitor cells.

Verification of a formula for determination of preexcision surgical margins from fixed-tissue melanoma specimens.

BACKGROUND: Recently our group reported on the shrinkage of 199 malignant melanoma surgical-excision specimens. In that report, a multivariate analysis revealed that the age of the patient was the only factor that significantly affected the percentage shrinkage of a surgical specimen. In addition, a formula was presented that extrapolates the actual surgical margins (in vivo) from the (contracted) fixed-tissue pathology report measurement and the reported in vivo lesion diameter. OBJECTIVE: The goals of this study are to verify that shrinkage of surgical specimens is approximately 20% and that the margin formula can be successfully applied to a different group of patients. METHODS: Four hundred seven patients with malignant melanoma were prospectively enrolled to measure preexcision (outlined with ink) surgical margins, fixed-tissue (contracted) surgical margins, and overall specimen shrinkage. RESULTS: It is verified that overall shrinkage of cutaneous surgical specimens is approximately 20%. Surgical specimens from patients younger than 50 years of age have approximately 25% shrinkage. Those specimens from patients 50 to 59 years of age have approximately 20% shrinkage and those from patients 60 years of age or older have about 15% shrinkage. The surgical margins predicted by the margin formula were within +/- 3.5 mm of the actual measured surgical margin 86.5% of the time. CONCLUSION: The actual surgical margins (in vivo) of a malignant melanoma can be reasonably estimated from the fixed-tissue pathology measurement via the margin formula. The shrinkage of a surgical specimen is 15% to 25% depending on the patient's age.

Recurrence rates of treated basal cell carcinomas. Part 4: X-ray therapy.

This is the fourth report in a series that reviews the experience in the Skin and Cancer Unit, from 1955 through 1982, with the treatment of basal cell carcinomas (BCCs). It concerns 862 primary (previously untreated) BCCs irradiated by a "standardized" x-ray therapy schedule. The overall 5-year recurrence rate for these lesions, as determined by the modified life-table method, was 7.4%. This rate was not significantly different from that experienced with 211 recurrent (previously treated) BCCs with a re-recurrence rate of 9.5% (P = .552). For the primary BCCs, multivariate analysis showed that increasing BCC diameter was the only independent risk factor for high recurrence rates (P = .003). The patient's age or sex, the duration of the BCC, the anatomic site of the BCC, or time-span treated (1955-1963, 1964-1972, 1973-1982) did not significantly affect the recurrence rate. Additional analysis showed that BCCs on the head less than 10 mm in diameter had a 5-year recurrence rate of 4.4% whereas those 10 mm or greater in diameter had a rate of 9.5%. Lastly, the proportion of recurrence-free treatment sites with a good or excellent long-term cosmetic outcome after x-ray therapy (63%) was lower than previous reports in this series with curettage-electrodesiccation (91%) and surgical excision (84%). Thus, if the long-term cosmetic outcome after treatment is not an overriding concern to the patient, x-ray therapy is an effective modality for many primary and recurrent BCCs.

Recurrence rates of treated basal cell carcinomas. Part 3: Surgical excision.

This is the third report in a series that reviews the experience in the Skin and Cancer Unit, from 1955 through 1982, with the treatment of basal cell carcinomas (BCCs). It concerns 588 previously untreated (primary) BCCs removed by surgical excision. The cumulative 5-year recurrence rate was 4.8%. This is a statistically significant lower recurrence rate (P = .034) than 135 previously treated BCCs that had a re-recurrence rate of 11.6%. For the primary BCCs, multivariate analysis showed that location on the head (P = .010) and being male (P = .004) were independent risk factors for recurrence. The patient's age, the duration of the BCC, its maximum diameter, or the time span (1955-1963, 1964-1972, 1973-1982) in which it was treated did not significantly affect the recurrence rate. The 5-year recurrence rate for BCCs excised from various anatomic sites were as follows: 1) neck, trunk, and extremities = 0.7%; 2) head--less than 6 mm in diameter = 3.2%; 3) head--6 to 9 mm in diameter = 8.0% (treated since 1964 = 5.2%); and 4) head--10 mm or more in diameter = 9.0%. Surgical excision is a highly effective method for removal of BCCs, and achieved a good to excellent cosmetic outcome in about 85% of the recurrence-free treatment sites.

Influence of gender on survival in patients with stage I malignant melanoma.

BACKGROUND: Women with stage I malignant melanoma (MM) have a survival advantage over men as judged by univariate analysis. However, on multivariate analysis, gender was found to be an independent predictor of survival in only 8 of 14 published studies. OBJECTIVE: This study attempts to explain the disparate findings for gender as a prognostic factor in different multivariate analyses. METHODS: Univariate and multivariate analyses were performed on 832 patients with stage I MM in the New York University Melanoma Cooperative Group (NYU-MCG) data base. The results were compared with those of 14 similar studies. RESULTS: In the NYU-MCG data base, gender, age of the patient, and number of mitoses per square millimeter were not independent factors on multivariate analysis, whereas thickness, anatomic site, and presence of ulceration were. The statistically significant difference in survival by gender on univariate analysis, in the NYU-MCG data base, could be explained by the differences in thickness and anatomic site of the MMs in the sexes. Comparison of these results with the reviewed reports from the literature consistently shows thickness and ulceration to be independent prognosticators of survival. Likewise, most authors agree that age is not an independent predictor. However, there is no consensus with respect to gender and site, each of which was found to be an independent predictor of survival in only about half the studies reviewed. CONCLUSION: The disparate findings for gender in different multivariate analyses are explained by a gender-related difference in anatomic distribution of MM. Gender and site appear to have a similar influence in multivariate analysis and thus either one or the other is a dominant factor in different multivariate analyses.

Level of education and the risk of malignant melanoma.

BACKGROUND: The risk for the development of malignant melanoma has been reported to be higher in persons with more formal education than in individuals with less. OBJECTIVE: To study whether those with more formal education are indeed at more risk for malignant melanoma than those with less formal education. METHODS: This case-control study explores the relation between education and melanoma risk by analyzing data collected by the American Cancer Society. A total of 1.2 million people were surveyed for a history of cancer and followed up for 6 years for the development of any cancer. In total, 2780 white persons had a history of malignant melanoma or developed malignant melanoma during the study period. The controls were age-, sex-, and geographically matched white persons selected from the remaining people enrolled. RESULTS: Both men and women were shown to have a statistically significant increase in the relative risk for malignant melanoma with increasing education level (p less than 0.001 and p = 0.001, respectively). This relation was more striking in men when the relative risk with 95% confidence interval was calculated by sex for each education level. CONCLUSION: Americans with more formal education are at greater risk for malignant melanoma than those with less education.

Determination of preexcision surgical margins of melanomas from fixed-tissue specimens.

The shrinkage of cutaneous surgical specimens of 199 malignant melanomas was analyzed. A formula was derived that makes it possible to calculate the in vivo (preexcision) specimen diameter from the in vitro (fixed-tissue) specimen diameter. The age of the patient was found to significantly influence specimen shrinkage and was incorporated into this shrinkage formula. The calculated in vivo specimen diameter was then used to determine the width of the in vivo surgical margins with reasonable accuracy. Thus this method permits calculation of the width of surgical margins from fixed-tissue specimens.