[Nosocomial outbreak of COVID-19 in an internal medicine ward: Probable airborne transmission]. / Brote nosocomial de COVID-19 en una planta de medicina interna: probable transmisión aérea.

Background and objectives: Despite the increasing evidence supporting the importance of airborne transmission in SARS-CoV-2 infection, it has not been considered relevant in the vast majority of reported nosocomial outbreaks of COVID-19. The aim of this study is to describe a nosocomial outbreak of SARS-CoV-2 infection whose features suggest that aerosol transmission had an important role. Methods: This is a descriptive analysis of a nosocomial outbreak of SARS-CoV-2 infection in an internal medicine ward that occurred in December 2020. All cases were confirmed by a positive PCR test for SARS-CoV-2. Results: From December 5 to December 17, 21 patients and 44 healthcare workers developed a nosocomial SARS-CoV-2 infection. Fifty-one of the 65 cases (78.5%) were diagnosed between December 6 and 9. The attack rate in patients was 80.8%. Among workers, the attack rate was higher in those who had worked at least one full working day in the ward (56.3%) than in those who had occasionally been in the ward (25.8%, p = 0.005). Three days before the first positive case was detected, 2 extractor fans were found to be defective, affecting the ventilation of 3 rooms. Sixteen cases were asymptomatic, 48 cases had non-severe symptoms, and 2 cases required admission to the intensive care unit. All patients eventually recovered. Conclusion: The high attack rate, the explosive nature of the outbreak, and the coincidence in time with the breakdown in air extractors in some rooms of the ward suggest that airborne transmission played a key role in the development of the outbreak.

Fluticasone in mild to moderate atopic dermatitis relapse: A randomized controlled trial.

BACKGROUND: The long-term efficacy of corticosteroids to prevent atopic dermatitis (AD) relapses has partially been addressed in children. This study compared an intermittent dosing regimen of fluticasone propionate (FP) cream 0.05% with its vehicle base in reducing the risk of relapse in children with stabilized AD. METHODS: A randomized controlled, multicentric, double-blind trial was conducted. Children (2-10 years) with mild/moderate AD (exclusion criteria: >30% affected body surface area and/or head) were enrolled into an Open-label Stabilization Phase (OSP) of up to 2 weeks on twice daily FP. Those who achieved treatment success entered the Double-blind Maintenance Phase (DMP). They were randomly allocated to receive FP or vehicle twice-weekly on consecutive days for 16 weeks. The primary study endpoint was relapse rate; time to relapse and severity of disease were also studied. Kaplan-Meier estimates were calculated. RESULTS: Fifty-four patients (29 girls) entered the OSP (23 mild AD) and 49 (26 girls) continued into the DMP. Mean age was 5.5 (SD: 2.8) and 5.1 (SD: 2.3) yrs for FP and vehicle groups, respectively. Four patients withdrew from the DMP (two in every group). Patients treated with FP twice weekly had a 2.7 fold lower risk of experiencing a relapse than patients treated with vehicle (relative risk 2.72, SD: 1.28; p=0.034). FP was also superior to vehicle for delaying time to relapse. Both treatment therapies were well tolerated. CONCLUSION: This long-term study shows that twice weekly FP provides an effective maintenance treatment to control the risk of relapse in children with AD.

Selective non-antibiotic treatment in sigmoid diverticulitis: is it time to change the traditional approach?

BACKGROUND: A growing body of knowledge is calling into question the use of antibiotics in acute diverticulitis (AD). Moreover, recent studies provide evidence regarding the security of treating patients with AD as outpatients. The aim of this study was to evaluate a restrictive antibiotic outpatient protocol for the treatment of mild-to-moderate episodes of AD. METHODS: All patients with symptoms of AD presenting to our emergency department were assigned a modified Neff stage. Patients with mild AD received outpatient treatment without antibiotics. Patients with mild AD and comorbidities were admitted to receive the same treatment. Patients with moderate AD were admitted for 48 h and were then managed as outpatients until they had completed 10 days of antibiotic treatment. RESULTS: Between April 2013 and November 2014, we attended 110 patients with a diagnosis of AD, 77 of whom we included in the study: 45 patients with mild AD and 32 with moderate AD. Of the patients with mild AD, 88.8 % successfully completed the non-antibiotic, non-admission treatment regime and 95.5 % benefited from a non-antibiotic regime, whether as outpatients or inpatients. A total of 88 % of patients with mild AD and 87.5 % of patients with moderate AD who met the inclusion criteria completed treatment as outpatients without incident. No major complications (abscess, emergency surgery) or deaths were recorded. CONCLUSIONS: Outpatient treatment without antibiotics for patients with mild AD is safe and effective. Patients with moderate AD can be safely treated with antibiotics in a mixed regime as inpatients and outpatients.

Ground cross-modal impedance as a tool for analyzing ground/plate interaction and ground wave propagation.

An analytical approach is investigated to model ground-plate interaction based on modal decomposition and the two-dimensional Fourier transform. A finite rectangular plate subjected to flexural vibration is coupled with the ground and modeled with the Kirchhoff hypothesis. A Navier equation represents the stratified ground, assumed infinite in the x- and y-directions and free at the top surface. To obtain an analytical solution, modal decomposition is applied to the structure and a Fourier Transform is applied to the ground. The result is a new tool for analyzing ground-plate interaction to resolve this problem: ground cross-modal impedance. It allows quantifying the added-stiffness, added-mass, and added-damping from the ground to the structure. Similarity with the parallel acoustic problem is highlighted. A comparison between the theory and the experiment shows good matching. Finally, specific cases are investigated, notably the influence of layer depth on plate vibration.

Effect of horizontal wave barriers on ground vibration propagation.

The aim of this article is to introduce a method to mitigate ground surface vibration through a flexural plate coupled to the ground and acting as a horizontal wave barrier. Using the thin plate hypothesis, two flexural plates are coupled to the ground, the first plate being the excited plate and the second plate the horizontal wave barrier. For instance, the first plate may represent a slab track and be excited by the tramway wheels. A solution to the problem can be found using a spatial two-dimensional Fourier transform of the elastodynamics equation for the ground and a modal decomposition for the flexural plate vibration. The authors show that vibration is substantially mitigated by the horizontal wave barrier and depends on its thickness and width. When the top surface wavelength becomes smaller than twice the plate width, the horizontal wave barrier acts as a wave barrier in the frequency range of interest, i.e., from 20 Hz.

Does stapled anopexy for bleeding haemorrhoids cure associated anaemia?

AIM: The aim of this study was to evaluate the effectiveness of stapled anopexy (SA) in patients with chronic bleeding haemorrhoids and secondary anaemia. METHOD: Our department performed 340 SA procedure per patient for haemorrhoids between January 1999 and December 2011. Fifty (14.7%) of these patients (25 male patients and 25 female patients) had anaemia (haemoglobin concentration < 13 g/dl in male patients and < 12 g/dl in female patients) secondary to chronic haemorrhoidal bleeding. Patients with colorectal bleeding and anaemia not caused by haemorrhoids were excluded. The mean (SD) age was 56.4 (13.9) years and the mean (SD) haemoglobin concentration was 9.2 (1.6) g/dl for male patients and 10.4 (1.2) g/dl for female patients. Five (10%) patients with anaemia had Grade II, 22 (44%) had Grade III and 23 (46%) had Grade IV haemorrhoids. The median (range) duration of postoperative follow-up was six (1-12) years. RESULTS: None of the patients required early postoperative admission or experienced early or late complications related to SA. The procedure was successful (normal haemoglobin concentration and no bleeding at 6 months postsurgery) in 45 (90%) patients. Of the five (10%) patients in whom SA was ineffective, one had Grade II, three had Grade III and one had Grade IV haemorrhoids. All these patients underwent Milligan-Morgan haemorrhoidectomy 3 months after SA. CONCLUSION: SA is an effective treatment for patients with bleeding haemorrhoids and subsequent anaemia. In our experience, the success rate was satisfactory and there were no serious complications.

Can advanced edge enhancement software improve image quality to visualise tubes, catheters and wires in digital chest radiographs?

INTRODUCTION: This study aimed to test whether Advanced Edge Enhancement (AEE) software could improve the localisation of tubes, catheters or wires, while also affecting the overall image quality in chest x-rays (CXR). METHODS: In total, 50 retrospective CXRs were included. All images were obtained utilising the Canon X-ray system (CANON/Arcoma Precision T3 DR System, Canon Europe, Amsterdam, NL) with a CXDI-810C wireless detector. A clinical image, plus three additional AEE algorithms were applied using post processing (two intensity variations 1 and 4) on all CXRs totalling 350 different images. Three radiologists evaluated the images using a subjective Absolute Visual Grading Analysis (VGA). The clinical images used in post processing were not applied as reference in the analysis. Each radiologist graded the images separately in a randomized order, with a score of three indicating suitability for diagnostic assessment. RESULTS: The three AEE algorithms contributed to an overall improvement (average 16-49%) in visualisation of tube, catheter or wire on CXR images. The Mann-Whitney U tests showed a statistically significant (p < 0.05) improvement in contrast resolution and sharpness, indicating an increased ability to differentiate tubes, wires or catheters tips from surrounding tissues. For the noise criterion, not applying any AEE algorithm showed a significantly higher homogeneity in soft tissue (p < 0.001), reducing the ability to visualise soft tissue. The high-intensity catheter algorithm was the only algorithm to achieve a statistically significant (p = 0.017) increase in the ability to differentiate pulmonary tissues of similar density. CONCLUSION: An overall improvement in the visualisation of tube, catheter and wire placement was obtained using the three AEE-algorithms. The bone and catheter algorithms showed the highest consistency, with the small structure algorithm underperforming in resolution and low contrast resolution. In general, image noise increased regardless of algorithm type or applied intensity. The AEE-algorithms should therefore be seen as a supplementary tool to the clinical image protocol, while having the potential to improve image quality to specific clinical situations. IMPLICATIONS FOR PRACTICE: AEE filtered images appear to be a supplement to the current practice of using CXRs in the diagnosis in placement of catheters, tubes and wires in the chest region. The use of AEE-algorithms has the potential to improve the daily work in clinical practice, which serves the basis for further investigation of its effect on radiographic practices.

Day case stapled anopexy for the treatment of haemorrhoids and rectal mucosal prolapse.

AIM: Stapled anopexy (SA) gives better early postoperative results than classical haemorrhoidectomy. The aim of this study is to demonstrate that SA is a safe and effective procedure for the treatment of haemorrhoids and rectal mucose prolapse in a day-case surgery programme. METHOD: From January 2000 to December 2008, 297 SA procedures were performed; 230 (77.4%) were performed in the Day Surgery Unit (DSU). Third- and fourth-degree haemorrhoids, second-degree haemorrhoids with no response to conservative treatment and several cases of rectal prolapse were included. The mean age of the patients in the series was 48.1 years (range 21-85). Preoperative preparation included phosphate enemas and antibiotic prophylaxis. Patients were operated on mainly under spinal anaesthesia. Day-case rate, postoperative pain (measured by a visual analogic scale, 1-10), admissions, re-admissions, early postoperative situation and recurrence were evaluated in the study. RESULTS: The overall DSU rate was 78%, with a progressive increase from 46% to 99% in 2008. One hundred and eighty-five patients (80%) had pain scores under 2; no patient had a pain score over 7. Eighteen (8%) patients required admission on the day of surgery. Late admission was needed for 3 (3%) patients. Thirty-three patients reported their situation as excellent, 174 as good, 20 as acceptable and three as bad when they answered a phone questionnaire 24 h after surgery. Overall, 20 (9%) patients had recurrence of symptoms. CONCLUSION: SA is a safe and effective procedure for prolapsing haemorrhoids in the day case setting. The recurrence rate is higher than that observed in classical haemorrhoidectomy. Most patients can be managed as day-cases.

[Postoperative unilateral acute glaucoma after abdominal surgery]. / Glaucoma agudo unilateral en el postoperatorio de cirugía abdominal.

An early and correct diagnosis substantially improves the post-operative prognosis of acute angle closure glaucoma (AACG). A 90 year-old woman was operated on for a right colon tumour by laparotomy, under combined anaesthesia without any adverse events. Twelve hours after the operation, the patient described recurrent periorbital pain in her right eye, with ocular hyperaemia, blurred vision, and unresponsive mydriasis. A diagnosis of AACG was made, but although conservative treatment was started YAG laser iridotomies were required to reduce the intraocular pressure. In the AACG postoperative period, as well as with an eye with several predisposed local factors including genetic predisposition, female gender, hypermetropia, increased lens thickness and small corneal diameter, can be added a pupillary block induced by adrenergic and anticholinergic drugs used in anaesthetic procedures. An acute and intensive periorbital or ocular pain, with or without visual disturbance, must aware the doctor. A differential diagnosis with other postoperative ocular diseases and cranial pain causes must be done.

Nosocomial outbreak of COVID-19 in an internal medicine ward: Probable airborne transmission.

BACKGROUND AND OBJECTIVES: Despite the increasing evidence supporting the importance of airborne transmission in SARS-CoV-2 infection, it has not been considered relevant in the vast majority of reported nosocomial outbreaks of COVID-19. The aim of this study is to describe a nosocomial outbreak of SARS-CoV-2 infection whose features suggest that aerosol transmission had an important role. METHODS: This is a descriptive analysis of a nosocomial outbreak of SARS-CoV-2 infection in an internal medicine ward that occurred in December 2020. All cases were confirmed by a positive PCR test for SARS-CoV-2. RESULTS: From December 5 to December 17, 21 patients and 44 healthcare workers (HCWs) developed a nosocomial SARS-CoV-2 infection. Fifty-one of the 65 cases (78.5%) were diagnosed between December 6 and 9. The attack rate in patients was 80.8%. Among HCWs, the attack rate was higher in those who had worked at least one full working day in the ward (56.3%) than in those who had occasionally been in the ward (25.8%; p = 0.005). Three days before the first positive case was detected, two extractor fans were found to be defective, affecting the ventilation of three rooms. Sixteen cases were asymptomatic, 48 cases had non-severe symptoms, and 2 cases required admission to the intensive care unit. All patients eventually recovered. CONCLUSION: The high attack rate, the explosive nature of the outbreak, and the coincidence in time with the breakdown in air extractors in some rooms of the ward suggest that airborne transmission played a key role in the development of the outbreak.

The influence of a novel edge enhancement software on image quality of DR hand images of patients with rheumatoid arthritis.

INTRODUCTION: This study aimed to evaluate the effects of a newly developed Advanced Edge Enhancement software (AEE) (Canon Europe, Amsterdam, NL) on image quality (IQ) of Digital Radiography (DR) hand images focusing on rheumatoid arthritis (RA). METHODS AND MATERIALS: Fifty posterior-anterior hand images with or suspected for RA were collected. For each of the 50 images, six copies were made with each their AEE algorithm settings. A total of 330 images (30 images iterated) were evaluated using relative Visual Grading Analysis (VGA) by three observers and combined into a VGA Score (VGAS). Second, 50 images of a technical Contrast Detail Radiography Phantom (CDRAD) was produced with three different AEE software settings, each at level 1,5 and without the AEE software yielding 350 CDRAD images. All images was analysed by the CDRAD Analyser and included for an objective analysis of the AEE software. RESULTS: The VGA study showed a significant difference in image quality between a standard image and images with AEE software applied. The average VGA score of the AEE software was better than the standard images (interval between 0.2 and 0.9). The AEE algorithms at level 5 scored significantly lower for noise but significantly higher for spatial resolution, sharpness and contrast in the VGA. The CDRAD images showed that all AEE algorithms had a statistically significant improvement for level 1 and deterioration for level 5 compared to the standard image. CONCLUSION: Overall the AEE algorithm: small structure level 1 showed an improvement of all IQ criteria in the VGA and a better technical IQ. IMPLICATIONS FOR PRACTICE: The AEE software ought to be considered as a useful addition to the current software, possibly enabling visualisation of structures currently visible.

Body temperature and response to thrombolytic therapy in acute ischaemic stroke.

OBJECTIVE: To determine the relationship between body temperature (BT), arterial recanalization, functional outcome, and hemorrhagic transformation (HT) of cerebral infarction in patients treated with i.v. tissue plasminogen activator (tPA). METHODS: We studied 254 patients treated with tPA within 3 h from stroke onset. National Institute of Health Stroke Scale score, BT, and transcranial Doppler ultrasound (n = 99) on admission and at 24 h were recorded. Hypodensity volume and HT were evaluated on CT at 24-36 h. Poor outcome (Rankin Scale > 2) was evaluated at 3 months. RESULTS: Arterial recanalization at 24 h was found in 70.7% of patients, HT in 24.8% (symptomatic in 4.7%) and poor outcome in 44.1%. Baseline BT was not associated with greater stroke severity at admission or at 24 h, HT or poor outcome. However, BT at 24 h correlated to stroke severity (P < 0.001) and hypodensity volume (P < 0.001) at 24 h, and was higher in patients who did not recanalize (P = 0.001), had symptomatic HT (P = 0.063) and poor outcome (P < 0.001). The adjusted odds ratio of poor outcome for patients with BT at 24 h > or = 37 degrees C was 2.56 (1.19-5.50, P = 0.016). CONCLUSION: Body temperature > or =37 degrees C at 24 h, but not at baseline, is associated with a lack of recanalization, greater hypodensity volume and worse outcome in stroke patients treated with tPA.

Soybean Seed Protein Genes Are Regulated Spatially during Embryogenesis.

We used in situ hybridization to investigate Kunitz trypsin inhibitor gene expression programs at the cell level in soybean embryos and in transformed tobacco seeds. The major Kunitz trypsin inhibitor mRNA, designated as KTi3, is first detectable in a specific globular stage embryo region, and then becomes localized within the axis of heart, cotyledon, and maturation stage embryos. By contrast, a related Kunitz trypsin inhibitor mRNA class, designated as KTi1/2, is not detectable during early embryogenesis. Nor is the KTi1/2 mRNA detectable in the axis at later developmental stages. Outer perimeter cells of each cotyledon accumulate both KTi1/2 and KTi3 mRNAs early in maturation. These mRNAs accumulate progressively from the outside to inside of each cotyledon in a "wave-like" pattern as embryogenesis proceeds. A similar KTi3 mRNA localization pattern is observed in soybean somatic embryos and in transformed tobacco seeds. An unrelated mRNA, encoding [beta]-conglycinin storage protein, also accumulates in a wave-like pattern during soybean embryogenesis. Our results indicate that cell-specific differences in seed protein gene expression programs are established early in development, and that seed protein mRNAs accumulate in a precise cellular pattern during seed maturation. We also show that seed protein gene expression patterns are conserved at the cell level in embryos of distantly related plants, and that these patterns are established in the absence of non-embryonic tissues.

[Giant simple hepatic cysts as dyspnea symptom in a 93-year-old patient]. / Quiste hepático simple gigante como causa de disnea en paciente de 93 años.

Giant simple hepatic cysts is generally asymptomatic in the 3% of cases of adult patients. We present a woman case of 93 years old who was diagnoses of giant simple hepatic cyst presented as dysnea. The management of this patient was with percutaneous aspiration and fenol alcohol. It made a review of cystic lesions of the liver and of simple hepatic cysts management.

Are the olive oil and other dietary lipids related to cancer? Experimental evidence.

There is a wealth of evidence supporting the relationship between dietary lipids and cancer, particularly those of the breast, colon and rectum and prostate. The main support comes from the international correlational studies and, especially, from experimental ones. The evidence from human analytical studies is less consistent because of several conflicting findings, probably due to methodological issues. Experimentally, it has been clearly demonstrated that quantity and type of dietary lipids as well as the particular critical phases of the carcinogenesis in which they act, are the essential factors in this relationship. Thus, whereas high dietary intake of n-6 polyunsaturated fatty acids (PUFA), primarily LA, and saturated fat has tumor-enhancing effects, long chain n-3 PUFA, CLA and GLA have inhibitory effects. Monounsaturated fatty acids (MUFA), mainly OA, present in high quantities in olive oil, seem to be protective although some inconsistent results have been reported. Bioactive compounds of virgin olive oil may also account for the protective effect of this oil, which is the main source of fat in the Mediterranean diet. Experimental studies have also provided evidence of several putative mechanisms of action of dietary lipids on cancer. Lipids can influence the hormonal status, modify cell membranes structure and function, cell signalling transduction pathways and gene expression, and modulate the function of the immune system. Although further studies are needed to evaluate and verify these mechanisms in humans, based on the multiple ways dietary lipids can act, they may have an important influence on tumorigenesis.

Ultrastructural modifications of intestinal and colonic mucosa induced by free or bound bile acids.

There is substantial evidence that bile acids may enhance the colon tumorigenesis induced by chemical carcinogens and that agents stimulating increased bile acid excretion may show similar promoting or enhancing activity. To test the premise that these agents might modify topographical ultrastructure of the small intestine and colon in the absence of carcinogens, rats were fed for 6 weeks on chemically defined diets containing 2% levels of three commercial bile acid sequestrants or 15% levels of wheat brain, cellulose, pectin, or alfalfa. Major qualitative and quantitative deviations from normal morphology were observed with each of the three sequestrants. Similar but less dramatic modifications occurred with diets containing alfalfa or pectin, both of which either "bind" bile acids in vitro or result in increased bile acid excretion. Bran and cellulose which neither "bind" bile acids nor increase their fecal excretion, were without significant effects on intestinal or colonic morphology. The morphological deviations observed with bile acid sequestrants were shown to be a direct response to free or bound bile acids by comparing the morphological modifications resulting from daily intracolonic infusions of free bile acids, sequestrant-bound bile acids, or the sequestrant alone.

The Differential Expression of Sucrose Synthase in Relation to Diverse Patterns of Carbon Partitioning in Developing Cotton Seed.

Developing cotton (Gossypium hirsutum L.) seed exhibits complex patterns of carbon allocation in which incoming sucrose (Suc) is partitioned to three major sinks: the fibers, seed coat, and cotyledons, which synthesize cellulose, starch, and storage proteins or oils, respectively. In this study we investigated the role of Suc synthase (SuSy) in the mobilization of Suc into such sinks. Assessments of SuSy gene expression at various levels led to the surprising conclusion that, in contrast to that found for other plants, SuSy does not appear to play a role in starch synthesis in the cotton seed. However, our demonstration of functional symplastic connections between the phloem-unloading area and the fiber cells, as well as the SuSy expression pattern in fibers, indicates a major role of SuSy in partitioning carbon to fiber cellulose synthesis. SuSy expression is also high in transfer cells of the seed coat facing the cotyledons. Such high levels of SuSy could contribute to the synthesis of the thickened cell walls and to the energy generation for Suc efflux to the seed apoplast. The expression of SuSy in cotyledons also suggests a role in protein and lipid synthesis. In summary, the developing cotton seed provides an excellent example of the diverse roles played by SuSy in carbon metabolism.

Multiple variability in the sequence of a family of maize endosperm proteins.

A collection of cDNA clones, corresponding to a group of maize endosperm proteins classified in the glutelin-2 (or reduced soluble proteins) and in the zein-2 subfractions, has been identified and characterized. The nucleotide sequence of three of these clones has been obtained and the amino acid sequence deduced. They appear to correspond to a small family of genes that are specifically expressed in immature endosperm simultaneously to zeins, the best characterized proteins from this tissue. Unlike zeins, the proteins of the glutelin-2 and zein-2 family contain sequences homologous to storage proteins from other cereals such as gliadins or hordeins. The cDNA clones encoding for the two types of proteins have been compared, and a high degree of homology has been observed for both the nucleotide and amino acid sequences. The differences existing in both the coding and non-coding regions allow the definition of multiple types of variability in their sequence. An hypothesis is proposed on how sequence diversity may have been generated in this particular class of plant proteins.

Effect of chronic intake of dietary fibers on the ultrastructural topography of rat jejunum and colon: a scanning electron microscopy study.

This report is an attempt to quantitate the observable topographical characteristics of small and large intestine after a specific dietary regimen under well-defined states of lipid absorption and metabolism. Alfalfa, white wheat bran, cellulose, and pectin were fed for 6 wk at a level of 15 g/100 g diet to four groups of rats (12 rats per dietary group). A 5th control group was maintained on Purina Rat Chow. Three animals from each group were blind-coded for morphological assessment. After anesthesia, the jejunum and mid-colon were removed and processed for scanning electron microscopy. Beginning with the mildest mucosal surface changes, the observed order in terms of increasing severity is bran less than cellulose less than pectin less than alfalfa. Our observations suggest that altered rates of cell loss in intestinal tract cytokinetics may be occurring with particular feeding patterns and should be considered as a possible mechanism in the nutritional consequences of dietary fiber intake.

Alzheimer's disease: interaction of apolipoprotein E genotype, family history of dementia, gender, education, ethnicity, and age of onset.

We evaluated 197 patients with predominantly late-onset Alzheimer's disease (AD) who belonged to several ethnic groups and analyzed the relationship of age of onset of AD to the presence or absence of several risk factors in this entire group of patients. The apolipoprotein E (apoE) epsilon 4 allele frequency, which was 29% in all patients (compared with the reported population mean of 13.7%, p < 0.001, did not vary significantly between ethnic groups but declined significantly with increasing age. The apoE epsilon 2 allele frequency was 3%, compared with the reported population mean of 7.4% (p = 0.001). The frequency of a positive family history of dementia in first-degree relatives (FH +) (overall 45%) did not vary significantly between ethnic groups. ApoE epsilon 4-positive (epsilon 4+) patients tended to have a higher FH + rate (58%) than apoE epsilon 4-negative (epsilon 4-) patients (40%) (p = 0.02). When the potential risk factors of gender, education, FH+ status, and epsilon 4+ status were examined together in a multiple linear-regression analysis, FH+ and epsilon 4+ status (but not gender or education) were significant (they were both associated with an earlier age of onset of AD). In a post-hoc analysis, we found a reduced age of onset in women, but not men, who were both FH + and epsilon 4+. Additionally, those probands who were epsilon 4+ were more likely to inherit the disease from their mothers than their fathers. The mechanism by which epsilon 4+ and FH+ status operate as risk factors may be by their effect on the age of onset of AD.