Mass Balance of the Greenland Ice Sheet at High Elevations

Comparison of ice discharge from higher elevation areas of the entire Greenland Ice Sheet with total snow accumulation gives estimates of ice thickening rates over the past few decades. On average, the region has been in balance, but with thickening of 21 centimeters per year in the southwest and thinning of 30 centimeters per year in the southeast. The north of the ice sheet shows less variability, with average thickening of 2 centimeters per year in the northeast and thinning of about 5 centimeters per year in the northwest. These results agree well with those from repeated altimeter surveys, except in the extreme south, where we find substantially higher rates of both thickening and thinning.

Greenland Ice Sheet: High-Elevation Balance and Peripheral Thinning

Aircraft laser-altimeter surveys over northern Greenland in 1994 and 1999 have been coupled with previously reported data from southern Greenland to analyze the recent mass-balance of the Greenland Ice Sheet. Above 2000 meters elevation, the ice sheet is in balance on average but has some regions of local thickening or thinning. Thinning predominates at lower elevations, with rates exceeding 1 meter per year close to the coast. Interpolation of our results between flight lines indicates a net loss of about 51 cubic kilometers of ice per year from the entire ice sheet, sufficient to raise sea level by 0.13 millimeter per year-approximately 7% of the observed rise.

Cisplatin-epirubicin-paclitaxel weekly administration with G-CSF support in advanced breast cancer. A Southern Italy Cooperative Oncology Group (SICOG) phase II study

PURPOSE

It has been shown in vitro that both cisplatin and epirubicin increase the antitumor activity of paclitaxel. Weekly administration could give a substantial improvement in the therapeutic index of cisplatin and paclitaxel. This study was aimed at defining the antitumor activity of a weekly cisplatin-epirubicin-paclitaxel (PET) administration in locally advanced or metastatic breast cancer patients.

PATIENTS AND METHODS

Sixty-eight breast cancer patients with advanced disease, who had not received prior chemotherapy (except adjuvant), received weekly cisplatin 30 mg/sqm, paclitaxel 120 mg/sqm and epirubicin 50 mg/sqm plus G-CSF (day 3-5), for a maximum of 12 cycles. Thirty-five patients had stage IIIB and 33 stage IV disease (14 with visceral metastases).

RESULTS

All patients were evaluable for response on an intent to treat basis. Overall, 21 complete and 38 partial responses have been recorded for an 87% ORR (95% CI = 76-94%). Fourteen CRs and 19 PRs have been registered in the 35 patients with locally advanced disease for a 94% ORR (95% CI = 81-99%) while 7 CRs and 19 PRs were observed in the 33 patients with metastatic disease for a 79% ORR (95% CI-61-91%). Surgery was performed in 33/35 women with locally advanced disease. Four of these patients (11%) showed no invasive cancer on pathologic examination, and in an additional 8 patients tumor < 1 cm was found in the breast. Only 4/33 patients who underwent surgery relapsed. The projected one-year RFS was greater than 80%. At an 11-month median follow-up (range, 3-19), 11 patients had progressed and 5 had died among the 33 patients with metastatic disease, the median progression-free survival in this group being 14 months. Severe hematologic toxicity was uncommon, grade 3-4 neutropenia and thrombocytopenia occurring in 32% and 4% of patients, respectively. Only 2 episodes of neutropenic sepsis were registered. Packed red blood cell transfusions were required in 7 patients. Vomiting, diarrhoea, mucositis and skin toxicity were severe in 6%, 9%, 10%, and 9% of patients, respectively. Peripheral neuropathy was observed in 47% of patients.

CONCLUSIONS

The weekly PET administration is a well tolerated and very effective approach in advanced breast cancer patients. It can produce a 40% clinical complete response rate, with a more than 10% pCR rate in patients with T4 disease, and an about 80% ORR in those with distant metastases. A phase III trial comparing PET with a standard every 3 weeks epirubicin-taxol administration is underway.

Comparative genomic hybridization (CGH) in dogs--application to the study of a canine glial tumour cell line

Recurrent chromosome aberrations are associated with many human cancers. Detailed cytogenetic analysis of tumors has benefited enormously from the development of molecular cytogenetic techniques based on fluorescence in situ hybridization (FISH). Comparative genomic hybridization (CGH) is a recently developed FISH technique that allows a rapid and comprehensive identification of imbalanced genomic material in tumour DNA. Comparative genomic hybridisation has been used widely in human medicine to evaluate losses and gains of tumour DNA isolated from a variety of sources, including fresh samples, cell-culture material and archival specimens, and has been instrumental in identifying sites in the human genome which contain genies involved in tumour development and progression. This report describes the first application of CGH in the dog, illustrated by the analysis of DNA isolated from a canine glial tumour cell line.

Towards achieving small-incision cataract surgery 99.8% of the time

A surgical approach designed to reliably attain the modern goal of small incision cataract surgery 99.8% of the time is described. Phacoemulsification as well as a manual small incision technique is utilised to achieve the desired outcome as often as possible and for all types of cataracts. The logic, and required surgical steps are described and illustrated. This surgical technique allows the advantages of small incision surgery to be reliably achieved. The method is flexible and allows decisions and steps to be modified depending on the skill and comfort zone of the individual surgeon.

Fludarabine induced intestinal pseudo-obstruction: case report and literature review

Intestinal pseudo-obstruction is a recognized but rare complication of chemotherapy. Vinca alkaloids and cytarabine have been reported to be associated with intestinal pseudo-obstruction. We report a case of fludarabine induced severe intestinal pseudo-obstruction in a 66-year-old man suffering from non-Hodgkin's lymphoma, and describe our successful management of this with a combination of parasympathomimetic and mechanical decompression, after failure of conservative management.

The role of central corneal thickness in the diagnosis of glaucoma

PURPOSE

To determine the effect of central corneal thickness (CCT) on applanation tonometry and any resultant misclassification of normals as ocular hypertension.

METHOD

The central corneal thickness was measured using the ultrasound pachometer in 50 normals, 25 glaucoma and 23 ocular hypertensive patients. The student's "t" test was used to determine any significant difference in CCT between the three groups.

RESULTS

There was a statistically significant difference in the mean CCT of the ocular hypertensives (0.574 +/- 0.033 mm) as compared to the glaucomas (0.534 +/- 0.030 mm) and normals (0.537 +/- 0.034 mm). Applying the described correction factor for corneal thickness, 39% of eyes with ocular hypertension were found to have a corrected IOP of 21 mmHg or less.

CONCLUSIONS

Increased corneal thickness in ocular hypertension may lead to an overestimation of IOP in 39% of cases. Measurement of central corneal thickness is advisable when the clinical findings do not correlate with the applanation IOP.

Incidence of and risk factors for hallucinations and delusions in patients with probable AD

OBJECTIVE

To examine the incidence of and risk factors for hallucinations and delusions associated with patients clinically diagnosed with probable AD.

BACKGROUND

Estimates of the incidence of psychosis in AD range widely from 10% to 75%. The risk factors for psychosis of AD are not known, although multiple studies indicate that AD patients with psychosis demonstrate greater cognitive and functional impairment.

METHODS

The authors conducted psychiatric evaluations of 329 patients with probable AD from the University of California at San Diego Alzheimer's Disease Research Center to determine the incidence of hallucinations and delusions. They examined data from annual clinical and neuropsychological evaluations to determine whether there were specific risk factors for the development of hallucinations and delusions.

RESULTS

Using Cox survival analyses, the cumulative incidence of hallucinations and delusions was 20.1% at 1 year, 36.1% at 2, 49.5% at 3, and 51.3% at 4 years. Parkinsonian gait, bradyphrenia, exaggerated general cognitive decline, and exaggerated semantic memory decline were significant predictors. Age, education, and gender were not significant predictors.

CONCLUSIONS

The authors found a relatively high incidence of hallucinations and delusions in patients diagnosed with probable AD and suggest that specific neurologic signs, cognitive abilities, and accelerated decline may be predictive markers for their occurrence.

Zoo-FISH analysis of dog chromosome 5: identification of conserved synteny with human and cat chromosomes

Conserved segments of synteny between the human genome and chromosome 5 (CFA 5) of the domestic dog (Canis familiaris) have been identified by reciprocal chromosome painting analysis. A CFA 5 paint probe was applied to human metaphase spreads, revealing distinct hybridisation sites on human (HSA) chromosomes 1, 11, 16, and 17. Paint probes for these human chromosomes were then hybridised to dog metaphase spreads, identifying the regions of CFA 5 with which homology is shared with the corresponding human chromosome. Application of the CFA 5 paint probe to metaphase spreads of the domestic cat (Felis catus, FCA) demonstrated hybridisation to cat chromosomes C1, D1, E1, and E2. Dog PCR primers for type 1 markers known to lie in the corresponding regions of HSA 11, 16, and 17 were used to isolate dog BAC clones representing four genes. Fluorescence in situ hybridisation analysis confirmed their localisation to CFA 5 and suggested that two of the conserved segments lie in opposing orientations on CFA 5, compared to the human chromosome concerned. A third segment appears to lie in the same orientation on both human and dog chromosomes. No suitable gene markers were available for analysis of the fourth segment. The significance of these findings is discussed with reference to current and future dog genome mapping efforts.

Developing child abuse prevention, identification, and treatment systems in Eastern Europe

Although the dissolution of the Soviet Union in 1989 brought a welcome end to the Cold War, the subsequent reestablishment of independent Eastern European countries revealed a host of problems. Among these was frequent child abuse and neglect, although lack of epidemiological data precluded any accurate estimate of prevalence. In an effort to address the problem of child abuse within this rapidly changing sociopolitical environment, the Children's Mental Health Alliance and the Soros Foundation organized the Eastern European Child Abuse and Child Mental Health Project in 1995. The authors describe the development of this multidisciplinary initiative involving collaboration with professionals from 17 countries in Eastern Europe. They highlight the goals, principles, and major phases of the project, as well as some of the challenges involved in its implementation.

Immunology of DNA vaccines: CpG motifs and antigen presentation

DNA vaccines elicit high levels of specific cytotoxic T lymphocytes and antibody production in numerous animal models. However, the specific immunological events which lead to this effective immune response remain unclear. Presentation of DNA-encoded antigens is particularly intriguing as there is now evidence to suggest that this occurs via both endogenous intracellular and cross-presentation. Further, it has been observed that many plasmid DNA vectors used in DNA vaccination contain CpG motifs--sequences of bacterial DNA which induce pro-inflammatory cytokines in various cells--and which thus provide a novel adjuvant for injected antigens. In this review we will discuss the effects these bacterial DNA sequences have on cells of the immune system, the immune response generated after DNA vaccination and the mechanisms by which DNA-encoded antigens are likely to be presented.

Human papillomavirus type, proliferative activity, and p53: potential markers of aggressive papillomatosis

CONTEXT

The predictive value of nuclear proliferation antigen (Ki-67), tumor suppressor gene product p53, and human papillomavirus type has not been evaluated for outcome of laryngeal papilloma.

OBJECTIVE

This study was designed to determine whether immunohistochemical analysis of Ki-67 and p53 and human papillomavirus typing by polymerase chain reaction are able to identify patients with a more aggressive course of laryngeal papillomatosis.

DESIGN

Immunohistochemistry and polymerase chain reaction were performed on archival, paraffin-embedded, laryngeal papillomatosis biopsy specimens at the time of diagnosis, at an intermediate time during treatment, and at the last procedure available. Staining indexes for Ki-67 and p53 were determined, and human papillomavirus type was analyzed for all biopsies.

PATIENTS

Twelve patients with recurrent laryngeal papillomatosis for at least 5 years were selected from patients treated at our institution during the last 20 years.

MAIN OUTCOME MEASURES

Separate analyses were conducted comparing average Ki-67 and p53 indexes against disease outcome, viral type, or average number of procedures per year. Associations were analyzed between virus type, average number of procedures per year, outcome, and histology.

RESULTS

No statistically significant associations were noted in Ki-67 or p53 indexes and outcome. Weak associations were noted for p53 indexes and procedures per year and virus type. Weak associations also were noted between virus type and development of neoplasia.

CONCLUSIONS

Our observations suggest that human papillomavirus typing may be helpful in identifying patients with aggressive recurrent laryngeal papillomatosis. The weak association between p53 indexes and procedures per year and virus type may have some predictive value in identifying aggressive lesions.

Subtrochanteric corrective osteotomy for the endoprosthetic treatment of high hip dislocation. Treatment and mid-term results with a cementless straight stem

Total hip arthroplasty is problematical in the case of high dislocation. To reposition the hip, a femoral shortening osteotomy is necessary in order to prevent damage to the neurovascular structures. This paper describes the implantation of a cementless straight stem in 15 patients using a simple technique with a simultaneous, derotating and shortening osteotomy. Femur fractures, pseudoarthroses, stem loosening, paresis and deep infections were not found. One socket loosening was revised. Fourteen patients had good or very good results in the Merle d'Aubigne score after a median of 4.3 (range 2-5.6) years of follow-up. The surgical technique described enables the initial stable fixation of a standard prosthesis without additional osteosynthesis. Additional advantages include a shorter duration of surgery, a lower complication rate and a more rapid consolidation of the osteotomy.

Differentiated dendritic cells expressing nuclear RelB are predominantly located in rheumatoid synovial tissue perivascular mononuclear cell aggregates

OBJECTIVE

Differentiated dendritic cells (DC) and other antigen-presenting cells are characterized by the nuclear location of RelB, a member of the nuclear factor kappaB/Rel family. To characterize and enumerate differentiated DC in rheumatoid arthritis (RA) peripheral blood (PB), synovial fluid (SF), and synovial tissue (ST), the expression and location of RelB were examined.

METHODS

RelB protein expression and cellular location were determined in RA PB, SF, and ST by flow cytometry and immunohistochemical analysis of purified cells or formalin-fixed tissue. DNA-binding activity of RelB was determined by electrophoretic mobility shift-Western immunoblotting assays.

RESULTS

Circulating RA PBDC resembled normal immature PBDC in that they did not express intracellular RelB protein. In RA ST serial sections, cells containing nuclear RelB (nRelB) were enriched in perivascular regions. A mean +/- SD of 84 +/- 10% of these cells were DC. The remaining nRelB+,HLA-DR+ cells comprised B cells and macrophages. Only 3% of sorted SFDC contained nRelB. However, RelB present in the nucleus of these SFDC was capable of binding DNA, and therefore capable of transcriptional activity.

CONCLUSION

Circulating DC precursors differentiate and express RelB after entry into rheumatoid ST. Differentiated DC can thus be identified by immunohistochemistry in formalin-fixed ST. Signals for DC maturation may differ between RA ST and SF, resulting in nuclear location of RelB predominantly in ST. This is likely to have functional consequences for the DC in these sites.

Allelic frequencies of host genetic variants influencing susceptibility to HIV-1 infection and disease in South African populations

OBJECTIVES

Limited information is available on the prevalence in African populations of host genetic polymorphisms conferring resistance to HIV-1 infection and disease. The objective of this study was to determine the allelic frequencies in South African populations of the chemokine receptor gene variants CCR5delta32, CCR5m303 and CCR2b-641 and the CXCR4 ligand gene variant SDF1-3'A.

METHOD

Cross-sectional study to determine the prevalence of these gene variants in South African subjects of African and European descent.

RESULTS

The CCR5delta32 genetic variant is rare in individuals of African origin, having an allelic frequency of 0.1% (n = 1247) compared with 9.8% (n = 144) in Caucasians. The CCR5m303 mutation was not detected in Africans (n = 687), whereas an allelic frequency of 0.9% (n = 145) was identified in Caucasians. The frequency of CCR2b-641 allele was 13.1% (n = 180) in Africans, which was significantly higher that the 7.2% (n = 146) detected in Caucasians. Finally the allelic frequency of the SDF1-3'A gene variant was only 1.0% (n = 198) in Africans compared with 19.8% (n = 145) in Caucasians.

CONCLUSIONS

These results indicate that genetic polymorphisms conferring resistance to HIV-1 infection are rare in the South African Black population. Except for the CCR2b-641 gene variant, individuals of African origin also had a much lower prevalence of genetic variants associated with prolonged disease progression.

Surface markers and transendothelial migration of dendritic cells from elderly subjects

Age-related changes of immune functions have been extensively investigated in both humans and animal models; nevertheless, the literature on potential alterations of dendritic cells, potent antigen presenting cells responsible for initiating immune responses, with aging is very scarce. We studied the immuno-phenotype of peripheral blood dendritic cells of elderly and young subjects by three-color flow cytometry. In addition, the capacity of transendothelial migration, an important step in inflammatory reactions, of peripheral blood dendritic cells of elderly subjects was investigated in an in vitro model. The expression of HLA-DR in the peripheral blood dendritic cells of the elderly subjects was significantly decreased when compared to the young control subjects. The expression of various other surface markers was similar in the young and elderly subjects. The ability of transendothelial migration of dendritic cells was found to be unimpaired in the elderly subjects. Both in the young and elderly subjects a significantly higher expression of CD29, CD86, HLA-DR, and HLA-DQ in the dendritic cells that had migrated through the endothelium in comparison to nonadherent, nonmigrating cells was found. In the migrating dendritic cells of the elderly subjects a significantly increased expression of CD11c was observed, whereas the expression of CD54 was significantly enhanced in the migrating dendritic cells of the young subjects only. In conclusion, our results demonstrate intact functions and a normal immunophenotype of dendritic cells derived from elderly subjects. Dendritic cells thus seem to be functional and therefore are not responsible for the well-known decline of T cell functions with aging.

Differential expression of osteonectin/SPARC during human prostate cancer progression

The precise mechanism(s) involved in invasion and metastasis of prostate cancer (CaP) is poorly understood. Osteonectin [ON (also known as SPARC or BM-40)] is an antiadhesive protein known to be involved in cell-matrix interactions, migration, and angiogenesis. In this report, we studied the expression of ON in human prostate cell lines, primary tumors, and metastatic foci of CaP. Reverse transcription-PCR and nonradioactive in situ hybridization (ISH) techniques were used to determine ON gene expression. Immunohistochemistry was carried out using the polyclonal antibody LF37 and/or the monoclonal antibody ON-mAb. Low to moderate levels of ON mRNA and protein were observed in glandular epithelial cells of normal tissue as well as a few primary CaPs. However, high levels of ON mRNA and protein were observed in most of the CaP metastatic foci, both osseous and nonosseous. This correlated well with our findings that multiple different CaP cell lines including four CaP cell lines derived from metastases show high levels of ON gene expression. Furthermore, ISH analyses and cell-specific reverse transcription-PCR evaluation showed that both the luminal and basal cells express the ON gene. We conclude that the differential pattern of ON expression suggests that it may play an important role in the progression of CaP.

A prospective trial of lansoprazole triple therapy for pediatric Helicobacter pylori infection

BACKGROUND

Triple therapy with a proton-pump inhibitor and two antibiotics is widely used in the treatment of Helicobacter pylori infection in adults. Experience with such therapy in the pediatric population is limited. This was a prospective, nonrandomized, open-label trial to evaluate safety and efficacy of a combination of lansoprazole, clarithromycin, and amoxicillin in symptomatic children with H. pylori infection.

METHODS

Children with H. pylori gastritis diagnosed by endoscopy performed for persistent nausea, vomiting, recurrent abdominal pain, and diarrhea with consistent histology were treated with the regimen of 0.45 mg/kg per day lansoprazole divided into two doses (maximum dose, 15 mg twice daily), amoxicillin 40 mg/kg per day in two doses (maximum dose, 1.0 g twice daily), and 250 mg clarithromycin twice daily (<10 years old) or 500 mg twice daily (>10 years old) for 2 weeks. Pre- and posttreatment endoscopic biopsy specimens were graded for the severity of gastritis and H. pylori density by a blinded pathologist. A questionnaire for assessing the severity of symptoms at the time of initial and second endoscopy were completed by patient and/or parent.

RESULTS

Thirty-two children (age range, 1-25 years; mean age, 11 years; 19 females, 13 males) were treated with this regimen during an 18-month period. H. pylori organisms with varying grades of gastritis were present in tissue specimens of all patients. Only 28 children had follow-up endoscopy, which showed eradication of H. pylori in 15 (54%) children. Histologic symptoms of gastritis improved after therapy in the whole group. Overall, symptoms of vomiting, abdominal pain, diarrhea, anorexia, and halitosis significantly improved (P < 0.05). Minor adverse effects of therapy occurred in 25% of patients.

CONCLUSIONS

Symptoms, histologic, and endoscopic findings improved after triple therapy in children with H. pylori gastritis; however, eradication of bacteria was achieved in only 56% of children.

A comparison of neonatal and adult multiorgan failure in a rat model

BACKGROUND/PURPOSE

To establish a neonatal animal model of multiorgan failure (MOF) for the histological study of the sequence and severity of neonatal MOF in comparison to a model of adult MOF.

METHODS

Neonatal and adult Sprague-Dawley rats received a single intraperitoneal injection of the inflammatory agent Zymosan. Rats were weighed; randomly killed on days 1 through 6; and heart, lung, liver, kidney, spleen, and ileocecum harvested for histological examination.

RESULTS

Neonatal animals receiving Zymosan showed a significant increase in total body weight not seen in adults. The sequence and severity of MOF-induced organ damage were strikingly different in adult and neonatal animals. Mild lung damage was seen as early as day 1 in adult rats receiving Zymosan. This progressed to moderate damage by day 2 and severe damage by day 6. Lungs of neonatal rats receiving Zymosan showed only mild damage by day 4, which had progressed no further by day 6. Mortality rate was not significantly different between adult and neonatal animals receiving Zymosan.

CONCLUSIONS

Zymosan can be used in a neonatal animal model to incite MOF. In the neonatal animal model of MOF there is (1) substantial early capillary leak as shown by increased body weight; (2) a unique progression of organ involvement-liver, kidney, lung compared with adult animals with MOF-lung, liver, kidney; and (3) relative sparing of the lung from injury. These findings are consistent with previous clinical observations of a difference in neonatal and adult MOF.

Weekly docetaxel plus gemcitabine or vinorelbine in refractory advanced breast cancer patients: a parallel dose-finding study. Southern Italy Cooperative Oncology Group (SICOG)

PURPOSE

The objective of this study was to determine the docetaxel MTD when combined with gemcitabine or vinorelbine in advanced breast cancer patients who had received previous anthracycline-based chemotherapy for advanced disease.

PATIENTS AND METHODS

Advanced breast cancer patients aged between 18 and 70 with ECOG PS 0-2 who had not responded to, or had relapsed after, first-line anthracycline-based chemotherapy, were randomized to receive either gemcitabine 1000 mg/m2 or vinorelbine 25 mg/m2 in combination with escalating doses of docetaxel (starting from 30 mg/m2), all on days 1 and 8 every three weeks. Escalation was stopped if > 33% of patients treated at a given dose level showed DLT at the first cycle.

RESULTS

A total of 34 patients with locally advanced (8) or metastatic disease (26) were treated, for a total of 94 cycles delivered. Nineteen patients received docetaxel in combination with gemcitabine and 15 with vinorelbine. All patients had been pretreated with anthracyclines, and 24 of 34 had also received weekly dose-dense paclitaxel. A docetaxel dose of 40/m2 proved to be safe when combined on days 1 and 8 with gemcitabine, while a dose of 35 mg/m2 was tolerated in combination with vinorelbine. Overall, nine episodes of DLT, all of them neutropenia, occurred at the first cycle. Considering all 94 cycles, grades 3 or 4 neutropenia and thrombocytopenia occurred in 15 (44%), and 7 (20%) patients. Non-hematologic toxicity was mild, except for three cases of grade 2 peripheral neuropathy. All patients were assessed for response on an 'intent-to-treat' basis. Overall, five partial responses were recorded (docetaxel + gemcitabine = 3 and docetaxel + vinorelbine = 2), for a 15% (95% CI: 5%-31%) overall response rate. Only 1 of 24 (4%) patients who had received weekly dose-dense paclitaxel responded to treatment.

CONCLUSIONS

The weekly docetaxel administration in combination with either gemcitabine or vinorelbine is a well-tolerated treatment for heavily pretreated advanced breast cancer patients. This approach, although sometimes capable of achieving a major response, does not seem advisable in advanced breast cancer patients refractory to both anthracyclines and paclitaxel.

Estrogen replacement therapy for treatment of mild to moderate Alzheimer disease: a randomized controlled trial. Alzheimer's Disease Cooperative Study

CONTEXT

Several reports from small clinical trials have suggested that estrogen replacement therapy may be useful for the treatment of Alzheimer disease (AD) in women.

OBJECTIVE

To determine whether estrogen replacement therapy affects global, cognitive, or functional decline in women with mild to moderate AD.

DESIGN

The Alzheimer's Disease Cooperative Study, a randomized, double-blind, placebo-controlled clinical trial conducted between October 1995 and January 1999.

SETTING

Thirty-two study sites in the United States.

PARTICIPANTS

A total of 120 women with mild to moderate AD and a Mini-Mental State Examination score between 12 and 28 who had had a hysterectomy.

INTERVENTIONS

Participants were randomized to estrogen, 0.625 mg/d (n = 42), or 1.25 mg/d (n = 39), or to identically appearing placebo (n = 39). One subject withdrew after randomization but before receiving medication; 97 subjects completed the trial.

MAIN OUTCOME MEASURES

The primary outcome measure was change on the Clinical Global Impression of Change (CGIC) 7-point scale, analyzed by intent to treat; secondary outcome measures included other global measures as well as measures of mood, specific cognitive domains (memory, attention, and language), motor function, and activities of daily living; compared by the combined estrogen groups vs the placebo group at 2, 6, 12, and 15 months of follow-up.

RESULTS

The CGIC score for estrogen vs placebo was 5.1 vs 5.0 (P = .43); 80% of participants taking estrogen vs 74% of participants taking placebo worsened (P = .48). Secondary outcome measures also showed no significant differences, with the exception of the Clinical Dementia Rating Scale, which suggested worsening among patients taking estrogen (mean posttreatment change in score for estrogen, 0.5 vs 0.2 for placebo; P = .01).

CONCLUSIONS

Estrogen replacement therapy for 1 year did not slow disease progression nor did it improve global, cognitive, or functional outcomes in women with mild to moderate AD. The study does not support the role of estrogen for the treatment of this disease. The potential role of estrogen in the prevention of AD, however, requires further research.

Luminal contents of benign and malignant prostatic glands: correspondence to altered secretory mechanisms

Recent changes in tissue fixation strategy, using glutaraldehyde, have clarified the secretory mechanisms of the normal prostate identifying cytoplasmic prostatic secretory granules, structures not preserved by formalin fixation. This normal secretory mechanism was absent in most adenocarcinomas, depicting an important metabolic change in transformed prostate cells. The current study further investigates differences between benign and malignant prostate secretion and relates them to the production of corpora amylacea by benign glands and crystalloids or mucin by cancer. In all normal prostate cells examined (6 cases), prostate secretory granules (PSG) were approximately 1-microm, brightly eosinophilic granules filling the cytoplasm of secretory cells and released in packets by a specialized apocrine cell structure. After apocrine decapitation and luminal dispersal, some of the cytoplasmic and PSG remnants condensed to form eosinophilic bodies (EB) with a glycoprotein rim and central protein core. EB were observed adsorbing and layering onto the surface of prostatic corpora amylacea representing their chief mode of enlargement. Biochemical analysis and x-ray diffraction studies confirmed sulfated glycosaminoglycans of similar structure as the main constituent of both PSG and corpora amylacea. Peripheral zone amphiphilic "dark cell" carcinoma (9 cases) contained almost no PSG, and showed neither apical decapitation nor EB formation, but mucin secretion was frequently detected. Crystalloids that share the same staining characteristics and sulfur content as PSG and corpora amylacea were identified in 3 selected "clear cell" carcinomas, all of which showed at least focal PSG secretion. The recognition of these differing secretory mechanisms and their deviation from normal further defines the histological criteria and spectrum of prostate malignancy.

A mathematical model for storage and recall functions in plants

In plantlets of Bidens pilosa L., under severely limiting environmental conditions the growth of the buds at the axil of the cotyledons (cotyledonary buds) is asymmetric (i.e. one of the buds starts growing before the other one), this asymmetry being oriented by the pricking of one of the cotyledons (i.e. pricking one cotyledon increases the probability that the bud at the axil of the other cotyledon be the first to start to grow). As long as the plant apex (i.e. the terminal bud) is present, the growth of the cotyledonary buds is inhibited (apical dominance), but the souvenir of the asymmetric message caused by sub-optimal environmental conditions and the orientation given by the cotyledon pricking is always present in the plant and can be revealed by removing the apex. Depending on the conditions for removing the plant apex and/or on the application of a variety of symmetrical treatments (e.g. thermal treatment, symmetrical pricking treatments, etc.) the stored asymmetry will either take effect (the bud at the axil of the non-pricked cotyledon will be the first to start to grow more often than the other one) or not (both buds will have equal chance to be the first to start to grow). This has been termed 'recalling' the stored asymmetry. By combining several successive symmetrical treatments, it is possible to reversibly switch on and off the recall function several times. This recall of the stored plant-asymmetry is analogous to the evocation function of a memory system. In this paper, we will present first a discrete logical version of the observed interaction structure between the main components of the bud growth system, then a continuous differential version, taking into account the main features of the observed experimental reality and trying to explain this phenomenology. The interaction structure of both the discrete and the continuous models presents similar positive and negative feedback circuits, necessary condition for observing multistationarity and stability.