A how-to guide for a precision medicine approach to the diagnosis and treatment of Alzheimer's disease

Article purpose

The clinical approach to Alzheimer's disease (AD) is challenging, particularly in high-functioning individuals. Accurate diagnosis is crucial, especially given the significant side effects, including brain hemorrhage, of newer monoclonal antibodies approved for treating earlier stages of Alzheimer's. Although early treatment is more effective, early diagnosis is also more difficult. Several clinical mimickers of AD exist either separately, or in conjunction with AD pathology, adding to the diagnostic complexity. To illustrate the clinical decision-making process, this study includes de-identified cases and reviews of the underlying etiology and pathology of Alzheimer's and available therapies to exemplify diagnostic and treatment subtleties.

Problem

The clinical presentation of Alzheimer's is complex and varied. Multiple other primary brain pathologies present with clinical phenotypes that can be difficult to distinguish from AD. Furthermore, Alzheimer's rarely exists in isolation, as almost all patients also show evidence of other primary brain pathologies, including Lewy body disease and argyrophilic grain disease. The phenotype and progression of AD can vary based on the brain regions affected by pathology, the coexistence and severity of other brain pathologies, the presence and severity of systemic comorbidities such as cardiac disease, the common co-occurrence with psychiatric diagnoses, and genetic risk factors. Additionally, symptoms and progression are influenced by an individual's brain reserve and cognitive reserve, as well as the timing of the diagnosis, which depends on the demographics of both the patient and the diagnosing physician, as well as the availability of biomarkers.

Methods

The optimal clinical and biomarker strategy for accurately diagnosing AD, common neuropathologic co-morbidities and mimickers, and available medication and non-medication-based treatments are discussed. Real-life examples of cognitive loss illustrate the diagnostic and treatment decision-making process as well as illustrative treatment responses.

Implications

AD is best considered a syndromic disorder, influenced by a multitude of patient and environmental characteristics. Additionally, AD existing alone is a unicorn, as there are nearly always coexisting other brain pathologies. Accurate diagnosis with biomarkers is essential. Treatment response is affected by the variables involved, and the effective treatment of Alzheimer's disease, as well as its prevention, requires an individualized, precision medicine strategy.

The tauopathies

Tauopathies are a clinically and neuropathologically heterogeneous group of neurodegenerative disorders, characterized by abnormal tau aggregates. Tau, a microtubule-associated protein, is important for cytoskeletal structure and intracellular transport. Aberrant posttranslational modification of tau results in abnormal tau aggregates causing neurodegeneration. Tauopathies may be primary, or secondary, where a second protein, such as Aß, is necessary for pathology, for example, in Alzheimer's disease, the most common tauopathy. Primary tauopathies are classified based on tau isoform and cell types where pathology predominates. Primary tauopathies include Pick disease, corticobasal degeneration, progressive supranuclear palsy, and argyrophilic grain disease. Environmental tauopathies include chronic traumatic encephalopathy and geographically isolated tauopathies such as the Guam-Parkinsonian-dementia complex. The clinical presentation of tauopathies varies based on the brain areas affected, generally presenting with a combination of cognitive and motor symptoms either earlier or later in the disease course. As symptoms overlap and tauopathies such as Alzheimer's disease and argyrophilic grain disease often coexist, accurate clinical diagnosis is challenging when biomarkers are unavailable. Available treatments target cognitive, motor, and behavioral symptoms. Disease-modifying therapies have been the focus of drug development, particularly agents targeting Aß and tau pathology in Alzheimer's disease, although most of these trials have failed.

Antiviral Essential Oils Incorporated in Nanocarriers: Strategy for Prevention from COVID-19 and Future Infectious Pandemics

BACKGROUND

Coronavirus has become a life-threatening disease and it is caused by severe acute respiratory syndrome (SARS). This new strain of coronavirus is not completely understood and to date, there is no treatment for coronavirus. Traditional ayurvedic medicines, mainly essential oils and Chinese herbs, have always played a vital role in the prevention and treatment of several epidemics and pandemics. In the meantime, guidelines of the ministry of AYUSH (Ayurveda, yoga, unani, siddha and homoepathy) include a traditional medicinal treatment for flu and fever and also recommended to boost immunity to prevent the spread of coronavirus. It is not possible to find which essential oil will offer the best level of protection. However, it is likely to assume that some essential oils are likely to offer a measurable level of defense in the same way they do with many other known viruses.

METHODS

Literature relevant to various essential oils having antiviral activity has been collected and compiled. Various nanocarriers of essential oils have also been stated. The database was collected using various search engines such as J-Gate, Google Scholar, Sci-Hub, PubMed, ScienceDirect, etc. Results: Essential oils contain active constituents such as phenolic compounds, terpenoids, alkaloids, phenyl propanoids, etc., which are responsible for their biological properties such as antiviral, antibacterial, antimicrobial, antioxidant activities and many more. However, the use of essential oils has always been limited due to poor solubility, solvent toxicity, volatility and low solubility. Many nanotechnology based carriers especially, liposomes, dendrimers, nanoparticles, nanoemulsion and microemulsion, etc. have been evidenced to overcome limitations associated with essential oils.

CONCLUSION

Several essential oils possess potent antiviral activity and are characterized by fewer side effects and are safe for human use. The nanocarrier systems of these oils have proved the potential to treat viral and bacterial infections. Lay Summary: Current COVID-19 era demands traditional treatment for immunity boost up as support therapy. Traditional ayurvedic medicines, mainly essential oils and Chinese herbs, have always played a vital role in the prevention and treatment of several epidemics and pandemics. Therefore, authors have summarized various essential oils having antiviral activity in current manuscript. Various nanocarriers of essential oils have been reported. Essential oils contain active constituents such as phenolic compounds, terpenoids, alkaloids, phenyl propanoids, etc., which are responsible for their biological properties such as antiviral, antibacterial, antimicrobial, antioxidant activity. However, the use of essential oils has always been limited due to poor solubility, solvent toxicity, volatility and low solubility. Many nanotechnology based carriers especially, liposomes, dendrimers, nanoparticles, nanoemulsion and microemulsion, etc. have been evidenced to overcome limitations associated with essential oils. The nanocarrier systems of these oils have proved the potential to treat viral and bacterial infections.

Influence of weather patterns and air quality on ecological population dynamics of ectoparasites in goats

Ectoparasitism has a damaging impact on the economy of goat production in India, but the factors influencing its distribution and dynamics are less explored. The present study was designed to investigate the influence of environmental factors like weather and air quality parameters on the occurrence of different types of ectoparasites in goats of two agro-climatic regions of India, viz. the Upper Gangetic Plain (UGP) and the Western Himalayas (WH). The prevalence survey for ectoparasitism among goats was conducted during the four distinct climatic seasons (winter, summer, monsoon, autumn) in both regions. The season-wise data of weather parameters (maximum and minimum temperature, relative humidity in morning and evening, sunrise and sunset time, mean daily temperature and relative humidity, daily variation in temperature and relative humidity, and day length) and air quality parameters (air quality index (AQI), particulate matter 2.5 μm (PM_2.5), particulate matter 10 μm (PM₁₀)) of both regions were analyzed in relation with the ectoparasitic prevalence pattern of corresponding regions. The results depict a noticeable correlation between the studied parameters and seasonal variation in the occurrence of each type of ectoparasites. This outcome on the interaction of studied parameters and ectoparasitism is intriguing and it opens a huge scope for future studies on the biometeorological aspects of host-parasite ecological interplay and evolutionary biology. The better understanding of climatological aspects of ectoparasite occurrences helps goat farmers in formulating appropriate timely intervention strategies for the economic control of ectoparasites, which in turn tackles ectoparasiticidal drug resistance and reduces threat of vector-borne diseases.

Awareness of Aromatherapy in Healing Stress and Body Pain among Dental Students

Aromatherapy is a style of practice in medicine where essential oils or other scents are used. These are either applied or directly inhaled to attain therapeutic benefit. Also they are used either by distillation with water or steam, or from the epicarp of citrus fruits by a mechanical process or by dry distillation. The mechanism of action in aromatherapy is unknown, but recent studies have shown that aromatherapy is also beneficial for a few health problems. A range of essential oils are found to possess various degrees of antimicrobial activity and are believed to own antiviral, nematicidal, antifungal, insecticidal, and antioxidant properties. Hence this treatment is also known as essential oil therapy. At the current situation of COVID -19 there is a prevalence of stress due to lockdown. This mental stress can adversely affect the physical and mental well-being of each and every individual. In order to overcome this stress this aroma therapy can be used. The main aim of the study is to assess the awareness of the use of aromatherapy in healing stress and body pain. This was a cross sectional study conducted among the dental students through a questionnaire. The questionnaire consisted of 10 questions and was circulated among the student population. The statistical analysis was done with the help of SPSS software version 2.0. The results concludes that most of the participants are aware of aromatherapy and the found it beneficial in healing stress and body pain.

Comparative Study on the Effectiveness of Aerobic and Resistance Exercise among South Indian Population

These days people are more about how they look and are giving lots of importance to fitness. Aerobic exercise improves cardiovascular adaptations that increases the peak of oxygen consumption and increases the strength. This is more preferred than resistance exercise as it can be done at home. This study was a prospective observational study. The pros were easy to create. It has gathered large data, it is economical and it has quick interpretation. The cons were the homogeneous population and its survey fatigue. To minimize the sampling bias we have to minimize error in questions and avoid loading questions.  This study contains 15 self-structured questionnaires which validated the study design, general population, methodology and its survey questionnaire are the internal validity. From the data analysis, the results showed that  95% feel it is good to do aerobics everyday and 5% feel it is not good to do aerobics everyday. 85% prefer walking is a good exercise and 15% prefer walking is not a good exercise. 85% feel aerobics tones our body, 15% feel aerobics does not tone our body. The aim of my study is to compare the effectiveness of aerobic and resistance exercise among the South Indian population.

Cognitive Impairment in Aging Physicians: Current Challenges and Possible Solutions

Aging physicians are at a higher risk of cognitive impairment, undermining patient safety and unraveling physicians' careers. Neurologists, occupational health physicians, and psychiatrists will participate in both health system policy decisions and individual patient evaluations. We address cognitive impairment in aging physicians and attendant risks and benefits. If significant cognitive impairment is found after an appropriate evaluation, precautions to confidentially support physicians' practicing safely for as long as possible should be instituted. Understanding that there is heterogeneity and variability in the course of cognitive disorders is crucial to supporting cognitively impaired, practicing physicians. Physicians who are no longer able to practice clinically have other meaningful options.

Heterogeneity of Alzheimer's disease: consequence for drug trials?

BACKGROUND

Alzheimer's disease is a heterogenous disorder with multiple phenotypes and genotypes, although they eventually converge to a final common clinicopathological endpoint. However, Alzheimer's disease drug trials do not account for the heterogeneity of the disease in trial design, impeding development of effective drugs.

DISCUSSION

Alzheimer's disease drug trials commonly have wide inclusion criteria that subsume multiple subtypes of the condition, with varying genotypes, phenotypes, and clinical courses. The outcome variables used in many trials may not be sensitive for the particular disease subtype and trials may not follow patients for the appropriate length of time necessary for the subtype of disease. Methods of stratifying treatment trial design to account for disease heterogeneity using algorithms incorporating demographics, neuroimaging, genetics, and clinical phenotypes, as well as more tailored outcome measures, are proposed to allow for personalized, precision medicine in Alzheimer's disease therapeutics development. Approaching Alzheimer's disease as a heterogenous disorder will likely improve yield in the search for effective treatments for the condition.

Th1/Th2 immune responses and oxidative stress in caprine flea allergy dermatitis

Flea allergy dermatitis (FAD) is the common, often neglected skin disease of goats caused mainly by Ctenocephalides felis. This study aimed to evaluate the immuno-oxidative pathobiology of FAD in goats. Twelve goats from the same herd were divided into two groups of six animals each. The group I (FAD) included animals with natural flea infestation and severe dermatitis lesions. The group II (Healthy control) animals were free from any parasitic infestation. To assess the pathological changes, the markers of oxidative stress (lipid peroxidation, reduced glutathione and total antioxidant capacity), and immune status (Tumour necrosis factor alpha, Interleukin 10, Transforming growth factor beta 1 and Th1/Th2 cytokine ratio) were evaluated from the blood and the serum samples. Remarkable oxidative stress and severe inflammatory response with Th2 cytokine dominance were observed in flea infested animals. Highly antigenic agents of fleas, either secretory or excretory or structural, induced severe inflammatory responses and significant oxidative stress in caprine FAD. Massive release of cytokines may be responsible for severe skin inflammation and lesions in FAD in contrast to other Th2 dominant ectoparasitic skin conditions of goats'.

Utilization of Euryale ferox Salisbury seed shell for removal of basic fuchsin dye from water: equilibrium and kinetics investigation

Euryale ferox Salisbury (E. ferox) is an environmentally and economically important wetland macrophyte.

A Comparison of Practice Pattern and Outcome of Twice-weekly and Thrice-weekly Hemodialysis Patients

Renal replacement therapy (RRT) options and practice varies in countries worldwide and is influenced by patients' choice, nephrologists' practice patterns, health system, payer practice, public policy, and socioeconomic factors. In India, hemodialysis (HD) remains the dominant RRT modality, and the practice is largely influenced by socioeconomics of the region of practice since third party payer is limited. Resource stretch to maximize outcome benefit is essential and HD session twice weekly is an improvized and cost-effective clinical practice. However, within the country, the patient characteristics, practice patterns, and outcomes of twice-weekly HD compared against patients dialyzed thrice weekly remain unclear. We did a retrospective analysis of patients who underwent twice- and thrice-weekly HD in a single center under similar settings. The patients on thrice a week dialysis were older and with a higher proportion of diabetics and were insured by private payers. Weight gain, ultrafiltration rates, blood pressures, and hemoglobin remained more favorable in the thrice-weekly patients. There was no significant difference in the hospitalization rates or mortality rates in the two groups. Patients who undergo twice-weekly HD have poorer intermediate measures of the outcome; although, morbidity and survival were not different in a small study population with short follow-up. The small sample size and the short duration of follow-up may limit the scope of findings of our study.

CD151-A Striking Marker for Cancer Therapy

Cluster of differentiation 151 (CD151) is a member of the mammalian tetraspanin family, which is involved in diverse functions such as maintaining normal cellular integrity, cell-to-cell communication, wound healing, platelet aggregation, trafficking, cell motility and angiogenesis. CD151 also supports de novo carcinogenesis in human skin squamous cell carcinoma (SCC) and tumor metastasis. CD151 interacts with α3β1 and α6β4 integrins through palmitoylation where cysteine plays an important role in the association of CD151 with integrins and non-integrin proteins. Invasion and metastasis of cancer cells were diminished by decreasing CD151 association with integrins. CD151 functions at various stages of cancer, including metastatic cascade and primary tumor growth, thus reinforcing the importance of CD151 as a target in oncology. The present review highlights the role of CD151 in tumor metastasis and its importance in cancer therapy.

Open-label, short-term, repetitive transcranial magnetic stimulation in patients with Alzheimer's disease with functional imaging correlates and literature review

BACKGROUND

Accumulating evidence suggests repetitive transcranial magnetic stimulation (rTMS) may be beneficial in ameliorating cognitive deficits in Alzheimer's disease (AD).

METHODS

AD patients received four high-frequency rTMS sessions over the bilateral dorsolateral prefrontal cortex (DLPFC) over two weeks. Structured cognitive assessments were administered at baseline, at 2 weeks after completion of rTMS, and at 4 weeks post treatment. At these same times, tolerant patients underwent functional magnetic resonance imaging (fMRI) while performing structured motor and cognitive tasks. We also reviewed literature regarding the effects of rTMS on cognitive function in AD.

RESULTS

A total of 12 patients were enrolled, eight of whom tolerated the fMRI. Improvement was seen in Boston Diagnostic Aphasia Examination tests of verbal and non-verbal agility 4 weeks post-treatment. The fMRI analysis showed trends for increased activation during cognitive performance tasks immediately after and at 4 weeks post-treatment. Our literature review revealed several double-blind, sham-controlled studies, all showing sustained improvement in cognition of AD patients with rTMS.

CONCLUSIONS

There was improvement in aspects of language after four rTMS treatments, sustained a month after treatment cessation. Our results are consistent with other studies and standardization of treatment protocols using functional imaging may be of benefit.

Current attitudes on self-use and prescription of hormone therapy among New York City gynaecologists

OBJECTIVE

The results of the Women's Health Initiative studies dramatically altered hormone therapy use around the world. In countries outside the United States, self-use in physicians remained unaltered while prescription use declined, implying that physicians may not concur with the findings. We wished to explore prevailing attitudes among American physicians by examining New York City obstetrician-gynaecologists' self-use and prescription use of hormone therapy.

STUDY DESIGN

All board-certified obstetrician-gynaecologists in New York City were invited to complete and return a detailed, previously validated questionnaire concerning hormone therapy use.

RESULTS

Two hundred and nine questionnaires were returned, for a response rate of 12% (209/1797). Gynaecologists agreed with the findings from the Women's Health Initiative studies regarding indications and contraindications to hormone therapy use. Even so, three-quarters of female gynaecologists and female partners of male gynaecologists (74%; 67/91) use or have previously used hormone therapy. However, only 27.3% (21/77) of male gynaecologists and 12.3% (14/114) of female gynaecologists recommend hormone therapy to all menopausal women regardless of contraindications. Gynaecologists remain divided in their attitude toward hormone therapy; 30% of gynaecologists felt that hormone therapy use generally prolonged women's lives, 36% felt it was not useful in prolonging women's lives, and 33% were unsure.

CONCLUSION

Since the publication of the Women's Health Initiative findings, New York City gynaecologists prescribe hormone therapy to fewer patients. However, they continue to self-use hormone therapy at much higher rates, even as they seem to concur with Women's Health Initiative recommendations, contributing to the ongoing controversy surrounding the validity of the Women's Health Initiative findings.

Which presidents are most memorable?

BACKGROUND/RATIONALE

Episodic memory loss is a hall-mark of Alzheimer's disease (AD), with recall of recent events becoming progressively difficult. A commonly used tool, the recollection of US presidents, was assessed in evaluating episodic versus semantic memory loss among AD patients compared with spouse controls.

METHODS

A total of 36 patients (12 men, 24 women) with possible or probable AD were asked to "give the names of 5 US presidents" and concurrently administered the Mini-Mental State Examination (MMSE). Twenty-three spouses (12 men, 11 women) were controls. The year 1980 demarcated "remote" versus "recent" presidents.

RESULTS

Patients were older, had lower MMSE scores (P < .001), and recalled fewer presidents than controls (P < .005), after controlling for age. Among patients, men were more educated than women (P < .05) and recalled more presidents (P < .001). No gender differences were observed in controls.

CONCLUSIONS

Patients with AD preferentially recalled remote presidents, supporting retention of semantic memory in this group. There were no gender differences between groups.

Prevalence of memory loss complaints and other symptoms associated with the menopause transition: A community survey

BACKGROUND

Complaints of memory loss are increasingly noted as part of the constellation of symptoms experienced in the menopause transition. Studies evaluating such complaints in this population have yielded varying results.

OBJECTIVE

The aim of this study was to determine if complaints of memory loss are a component of the menopause transition and a part of the menopausal symptom complex in a population of women not selected for menopausal symptoms.

METHODS

Faculty members of a Long Island, New York, school district were asked to participate ina survey of menopausal symptoms. Demographic data were analyzed using chi(2) statistics. The presence or absence of memory complaints, hot flashes/night sweats, vaginal dryness, depression, reduced libido, and incontinence were analyzed as dichotomous variables in a logistic regression analysis after adjusting for demographic differences.

RESULTS

Seventy-two percent (375/521) of the faculty members in the school district were eligible;of these, 217 (58%) completed the survey. After excluding pregnant women, those with hysterectomies or other nonmenopausal causes of amenorrhea, and those aged <30 or >60 years, 151 women were included in the analysis. Of these, 103 (68%) were experiencing natural menopause or perimenopause and 48 (32%) had no changes in menstrual cycle (the comparison group). The menopausal women were significantly older than the women in the comparison group (mean [SD] 51.2 [5.0] years vs 39.6 [7.2] years; P < 0.001), and they were more likely to be white than the women in the comparison group (P < 0.001). Menopausal women were several-fold more likely to complain of memory loss (odds ratio [OR], 3.2; 95% CI, 1.2-8.8; P < 0.02), hot flashes/night sweats (OR, 4.3; 95% CI, 1.4-13.3; P < 0.01), and reduced libido (OR, 4.5; 95% CI, 1.3-15.7; P < 0.02) than were women in the comparison group, after adjusting for differences in age and race. There were no significant differences in the prevalence of depression, vaginal dryness, or incontinence.

CONCLUSIONS

In our exploratory survey, complaints of memory loss were a part of the symptom complex of the menopause transition, as were hot flashes and reduced libido. Longitudinal followup of women with these symptoms may be helpful in understanding the menopause transition in women.

Ovarian sex cord tumour with annular tubules diagnosed by fine needle aspiration cytology--a case report

Sex cord tumor with annular tubules (SCTAT) is a rare ovarian neoplasm with distinctive morphological features whose cytological features have rarely been described. We report a case of SCTAT diagnosed on fine needle aspiration cytology (FNAC) with a brief review of literature. A 35 year old female presented with recurrent abdominal mass. Fine needle aspiration was done under ultra sound guidance. Cytology smears showed three dimensional tubular structures, metachomatic hyaline masses and uniform neoplastic cells dispersed and in cohesive clusters. Cell block study showed the characteristic simple and complex tubules leading to the diagnosis. The cytological findings of a rare ovarian neoplasm are described, which is only the third such report in English literature. The cytologic features of ovarian SCTAT are as distinctive as its histologicfeatures. Cell block study brings out the distinctive architecture of the tumor and helps in differentiating it from other closely related tumors.

A comparison of family history of psychiatric disorders among patients with early- and late-onset Alzheimer's disease

OBJECTIVE

Both early-onset Alzheimer's Disease (EOAD) and late-onset Alzheimer's Disease (LOAD) present with cognitive and psychiatric features. Some studies suggest that EOAD patients are more likely than LOAD patients to have psychiatric symptoms. If this is true, relatives of EOAD patients with a similar clinical presentation may be more likely to be misclassified as having a primary noncognitive psychiatric disorder rather than a dementing disorder. Family history studies may underestimate familial aggregation of EOAD.

METHODS

The authors compared the presence of psychiatric symptoms in parents and siblings of 131 EOAD patients (diagnosed at or before age 60), with the parents and siblings of 131 LOAD patients (diagnosed at or after age 65). Early onset Alzheimer's Disease and LOAD patients were matched for diagnosis (probable versus possible AD), gender, and ethnic group. Logistic regression analysis was performed on the outcome variable of patient group (EOAD, LOAD) with family history of psychiatric symptoms as the risk factor, adjusting for family size and patient's education.

RESULTS

There was a nearly two and one-half-fold increase in family history of psychiatric symptoms among EOAD patients when compared with LOAD patients (RR = 2.4; 95% C.I. 1.2-4.7).

CONCLUSIONS

The authors found preliminary evidence of a higher prevalence of a history of psychiatric symptoms among relatives of EOAD patients when compared to LOAD patients. This may be due to differential misclassification of AD, a syndromic disorder with both noncognitive psychiatric and cognitive deficits in relatives of EOAD patients. Alternatively, shared genetic or other familial etiologies may underlie subtypes of EOAD and some psychiatric disorders.

The role of routine laboratory studies and neuroimaging in the diagnosis of dementia: a clinicopathological study

OBJECTIVE

To determine the neuropathological diagnoses of longitudinally followed patients with potentially reversible causes of dementia and to examine the results of the "dementia work-up," especially neuroimaging, by comparison with the pathological diagnosis.

DESIGN

A neuropathologic series of 61 consecutive patients, with review of clinical, laboratory, neuroimaging, and pathological results.

RESULTS

Of the 61 patients, forty-eight (79%) had a clinical diagnosis of probable or possible Alzheimer's disease (AD). Compared with the pathological diagnosis, the sensitivity and specificity of the clinical diagnosis of AD were 96% and 79%, respectively. Of the 61 patients, 9 had abnormal laboratory tests, the correction of which did not improve the subsequent course. These patients were found to have AD8 and frontotemporal dementia on pathology. In two patients, neuroimaging was helpful in the clinical diagnoses of frontotemporal dementia and progressive supranuclear palsy (PSP). Neuroimaging revealed cerebrovascular disease in 18 patients, only two of whom were suspected clinically. Pathology confirmed AD in 17 and PSP in 1 of these patients. Sensitivity and specificity for the clinical diagnosis of cerebrovascular disease in comparison with pathology were 6% and 98%, respectively. With the added information from neuroimaging, that sensitivity increased to 59% and specificity decreased to 81%.

CONCLUSIONS

All cases with abnormal laboratory or neuroimaging results had AD or some other neurodegenerative disease on pathology. The "dementia work-up" did not reveal any reversible causes for dementia in this group of patients. Neuroimaging may have a role, especially in the diagnosis of possible AD with concomitant cerebrovascular disease.

Approaches to memory loss in neuropsychiatric disorders

Many neuropsychiatric disorders affect memory. Brain regions important in the neuroanatomic substrate of memory include the hippocampus, and sections of the frontal, temporal, and parietal cortices and the thalamus. Acetylcholine and many other neurotransmitters and neuromodulators including dopamine, glutamate, GABA, the catecholamines, and estrogen modulate cognitive function. Treatment approaches to memory loss typically use Alzheimer's dementia as the template, and are discussed in this report.

Novel presenilin 1 mutations associated with early onset of dementia in a family with both early-onset and late-onset Alzheimer disease

Two children of an adult with early-onset, autopsy-confirmed Alzheimer disease (AD) developed dementia in their late 20s and were subsequently found to have novel mutations in codon 434 of the presenilin 1 (PS1) gene on chromosome 14, a G-to-T substitution at nucleotide 1548 and a C-to-G substitution at nucleotide 1549. The younger of the 2 children had AD confirmed at postmortem examination. The disease course in these 3 individuals was characterized by cognitive and behavioral problems accompanied by myoclonus, seizures, and aphasia within 5 years after onset. Two grandparents had clinically diagnosed AD with stroke beginning at ages 78 and 66 years, but neither had a PS1 mutation. No other living family member was demented, nor did any other family member have the PS1 mutation. We conclude that the affected parent of the proband was a likely recent founder for these novel mutations in PS1. The family demonstrates the clinical and genetic heterogeneity of AD. Arch Neurol. 2000;57:1454-1457

Validity of family history for the diagnosis of dementia among siblings of patients with late-onset Alzheimer's disease

We examined 180 siblings of 127 probands with probable or possible Alzheimer's dementia (AD) in a family study of AD. The overall sensitivity of a simple family history questionnaire was 64% and the specificity was 84%. Sensitivity improved 90-100% with minimal decline in specificity when we considered clinic-based vs. population survey patients. Higher education among informants and the availability of a spouse or a sibling as informant significantly increased sensitivity. Awareness of such factors may improve the yield of the family history in AD using a simple questionnaire.

Familial aggregation of Alzheimer disease among whites, African Americans, and Caribbean Hispanics in northern Manhattan

BACKGROUND

Alzheimer disease (AD) aggregates in families.

OBJECTIVE

To compare the familial aggregation and lifetime risk of AD to the age of 90 years in the first-degree relatives of patients with AD and unrelated controls among Caribbean Hispanics, African Americans, and whites in Washington Heights, Manhattan, New York, NY.

METHODS

Family history of AD and demographic information were obtained from informants of 435 patients with probable or possible AD concerning 1577 siblings and parents and from 1094 controls without dementia concerning 3952 siblings and parents.

RESULTS

Lifetime risk of AD to the age of 90 years was 25.9% in relatives of patients and 19.1% in relatives of controls. Rate ratio (RR) for AD in relatives of patients compared with relatives of controls was 1.5 overall (95% confidence interval [CI], 1.2-1.9), and was greater for siblings (RR, 1.8; 95% CI, 1.2-2.5) than for parents (RR, 1.2; 95% CI, 0.9-1.8). Within ethnic groups, RR for AD among relatives was significantly elevated in whites (RR, 2.0; 95% CI, 1.2-3.3) and Hispanics (RR, 1.5; 95% CI, 1.1-2.1), but the difference did not reach statistical significance in African Americans (RR, 1.4; 95% CI, 0.7-2.7). Risk of AD was greater among relatives who were women compared with men (RR, 1.5; 95% CI, 1.2-1.9).

CONCLUSIONS

Familial aggregation of AD was increased among families of patients compared with those of controls in all 3 ethnic groups. Risk of AD was highest among siblings and women relatives.

A clinicopathological comparison of community-based and clinic-based cohorts of patients with dementia

OBJECTIVES

To compare the sensitivity and specificity of the clinical diagnosis of Alzheimer disease, the distribution of pathological causes, and the demographic and clinical characteristics of 2 different groups of patients with dementia.

DESIGN

Retrospective clinicopathological study.

SETTING

A memory disorder clinic in a university hospital and a multiethnic community.

PATIENTS

Sixty-three patients from a memory disorder clinic and 26 patients from a large community-based study who underwent autopsy after clinical evaluation.

MAIN OUTCOME MEASURES

Differential distribution of clinical and pathological findings, with clinicopathological correlations.

RESULTS

Clinic patients were younger at diagnosis, more educated, and more likely to be white. Of the 63 clinic patients we evaluated, 29 (46%) had a pathological diagnosis of definite AD, 15 (24%) had a diagnosis of mixed AD, and 19 (30%) had a diagnosis of another type of dementia. The pathological diagnoses in the community patients were distributed as follows: 6 (23%) had definite AD, 6 (23%) had mixed AD, 6 (23%) had cerebrovascular disease, and 8 (31%) had another type of dementia. The difference in distribution of pathological diagnoses between these 2 groups was only significant for cerebrovascular diseases. For patients seen at the clinic, the sensitivity of the clinical diagnosis of AD was 98% and the specificity was 84%; for the community group, the sensitivity was 92% and the specificity was 79%.

CONCLUSIONS

The difference in sensitivity and specificity of clinical diagnosis was not statistically significant between the groups of clinic patients and community patients. Dementia associated with cerebrovascular disease was more prevalent in the community sample. This difference may be attributable to clinical and demographic differences between the 2 groups.

The insulin-like growth factor binding protein superfamily: new perspectives

The insulin-like growth factor (IGF) binding proteins (IGFBPs) were initially identified as carrier proteins for IGF-I and IGF-II in a variety of biologic fluids. Their presumed function was to protect IGF peptides from degradation and clearance, increase the half-life of the IGFs, and deliver them to appropriate tissue receptors. The concept of IGFBPs as simple carrier proteins has been complicated, however, by a number of observations: 1) the six IGFBPs vary in their tissue expression and their regulation by other hormones and growth factors; 2) the IGFBPs are subjected to proteolytic degradation, thereby altering their affinities for the IGFs; 3) IGFBP-3 and IGFBP-5, in addition to binding IGFs, also can associate with an acid-labile subunit, thereby increasing further the half-life of the IGFs; 4) in addition to modifying the access of IGF peptides to IGF and insulin receptors, several of the IGFBPs may be capable of increasing IGF action; 5) some of the IGFBPs may be capable of IGF-independent regulation of cell growth; 6) some of the IGFBPs are associated with cell membranes or possibly with membrane receptors; and 7) some of the IGFBPs have nuclear recognition sites and may be found within the nucleus. Additionally, a number of cDNAs identified recently have been found to encode proteins that bind IGFs, but with substantially lower affinities than is the case with IGFBPs. The N-terminal regions of the predicted proteins are structurally homologous to the classic IGFBPs, with conservation of the cysteine-rich region. These observations suggest that these low-affinity binders are members of an IGFBP superfamily, capable of regulating cell growth by both IGF-dependent and IGF-independent mechanisms.insulin-like growth factor, insulin-like growth factor binding proteins.

Influence of APOE genotype on familial aggregation of AD in an urban population

OBJECTIVE

To examine the influence of the proband's APOE genotype on AD among first-degree relatives in a community-based study of African Americans, whites, and Caribbean Hispanics.

METHODS

History of AD and demographic information were obtained on 1,073 siblings and parents of 312 patients with AD and 2,722 siblings and parents of 802 nondemented controls. APOE genotyping was performed on all 1,114 patients and controls.

RESULTS

A higher proportion of patients with AD (35%) than controls (27%) had one or more APOE-epsilon4 alleles (p = 0.03). When compared with relatives of controls without an APOE-epsilon4 allele, the risk for AD was increased in first-degree relatives of both patients (rate ratio [RR] = 1.9, 95% confidence interval [CI] = 1.2 to 3.1) and controls (RR = 1.8, 95% CI = 1.2 to 2.6) with one or more APOE-epsilone alleles, regardless of ethnic group. There was a similar trend of increased risk in relatives of patients without an APOE-epsilon4 allele, but this was limited to Hispanics and African Americans.

CONCLUSIONS

The presence of an APOE-epsilon4 allele increases risk for AD among first-degree relatives, regardless of the probands' disease status, among all ethnic groups. Relatives of patients without an APOE-epsilon4 allele were also at increased risk for AD among Hispanics and African Americans, suggesting that other genes or risk factors may influence risk.

Alois Alzheimer, neuroscientist (1864-1915)

Little is known about the person behind the eponymous dementia, Alois Alzheimer. We wished to study his life and contributions to the field of neuroscience. All cited articles about Alzheimer by his contemporaries and selected correspondence by him was translated from German. Additional personal information was obtained from his granddaughter. Alois Alzheimer made seminal contributions to the field of neuroscience, not only through his own research but also through the numerous scientists and physicians whom he taught. His contributions made a lasting impact not only in the area of Alzheimer disease but also other aspects of brain disease. In addition, he emerges as a complex person who coped successfully with numerous personal and career-related dilemmas that remain relevant in the academic environment today.

Truncated forms of the insulin-like growth factor II (IGF-II)/mannose 6-phosphate receptor encompassing the IGF-II binding site: characterization of a point mutation that abolishes IGF-II binding

Complete understanding of the functional significance of insulin-like growth factor II (IGF-II) binding by the IGF-II/mannose-6-phosphate (Man-6-P) receptor requires mapping and ultimately mutational analysis of the receptor's IGF-II binding domain. Recent advances have localized the IGF-II binding site to extracytoplasmic repeats 10-11. To improve resolution of the binding site map, a nested set of epitope-tagged, truncated forms of the human IGF-II/Man-6-P receptor were transiently expressed in COS-7 cells. The IGF-II binding properties of truncated receptors immunoprecipitated from cell lysates and conditioned media were determined by affinity cross-linking. From the largest truncated receptor, encompassing extracytoplasmic repeats 8-11 (M(r) 68 K), through the smallest, comprised primarily of repeat 11 (M(r) 23 K), all were able to bind and cross-link to IGF-II. As a group, the truncated receptors had similar affinities for IGF-II, but with relative binding affinities 5-to 10-fold lower than those of full-length receptors. A point mutation substituting threonine for isoleucine at residue 1572, located in the NH2-terminal half of repeat 11, completely abolished IGF-II binding. We conclude that repeat 11 of the IGF-II/Man-6-P receptor's extracytoplasmic domain contains the minimal elements required for binding and cross-linking to IGF-II, and that lle1572 and other residues within the NH2-terminal half of repeat 11 are particularly important for IGF-II interaction.