Senile Individuals Research Articles

유산균] 프로바이오틱 유산균

불가리아 사람들이 장수하는 것은 요구르트를 많이 섭취하여 유산균이 장내의 독소 생성 세균을 억제하기 때문이라고 한다. 젊을 때는 사람의 장 내용물 1 g당 100억 마리 이상의 <TEX>$Bifidobacterium$</TEX>이 살지만 노쇠하거나 병들면서 줄어들고 <TEX>$Clostridium$</TEX> 등의 유해균이 많아진다. 그래서 인공적으로 장내의 비피도박테리움을 증가시키면 유해세균이 억제되어 건강하고 장수한다고 한다. 이를 위하여 섭취하는 미생물을 probiotic 미생물이라고 하며, 주로 유산균이 사용된다. 프로바이오틱 미생물은 항생제와 같이 유해균을 죽이는 것이 아니라 유해균과 공생하면서 유해균을 억제하여 건강을 증진, 즉 숙주(사람)를 증생(增生)시킨다. 그래서 유산균을 주체로 하는 프로바이오틱 미생물과 그 제품은 변비, 설사, 장염, 혈중 콜레스테롤, 암 등을 예방 내지 치료하고 정장(淨腸) 작용으로 건강을 향상시킨다고 하여 시장이 계속 확대되고 있다. 그러나 국내 프로바이오틱스 제품은 종균을 대부분(90%) 수입하여 사용하므로 한국인의 체질에 적합하지 않을 가능성이 있다. 그래서 E사는 자체 개발한 미생물로 제품을 생산하고 있다. 본 논문에서는 유산균을 주체로 하는 프로바이오틱 미생물과 제품의 효과와 특성, 종류, 시장 등 전반적인 면을 살펴 보았다. It is said that the reason Bulgarians enjoy longevity is that they have a lot of yogurt, whose <TEX>$Lactobacillus$</TEX> controls intestinal poison-producing germs. In young individuals, the number of bifidobacteria exceeds 10 billion per 1 g of intestinal content, but this number decreases for older or senile individuals, who have a larger number of harmful microorganisms such as <TEX>$Clostridium$</TEX>. In addition, it is well known that artificially increasing intestinal bifidobacteria can help control harmful microorganisms and thus facilitate a healthier and longer life. The microorganisms used for artificial spawn are referred to as probiotic microorganisms, and in general, lactic acid bacteria(LAB) are used. Unlike antibiotics, which kill harmful microorganisms, probiotic microorganisms coexist with and control them, while improving the health of the individual, that is, they can improve and invigorate host cells. Because probiotic microorganisms and its products based on LAB are known to help prevent and treat constipation, diarrhea, intestinal inflammation, and blood cholesterol and generally improve health through the purification of intestines, its market has been continuously expanding. Korea imports approximately 90% of spawn and uses them. It is likely that they are not appropriate for Korean's physical condition. Thus, considering this problem into account, Entecbio, a biotech firm in Korea, has produced various products by using its proprietary microorganisms. In this paper, the effects, characteristics, and kinds of products from based on proprietary microorganisms, with its prospect for market, etc., are generally examined.

¿Existe la enfermedad de Alzheimer en todos los primates? Afección de Alzheimer en primates no humanos y sus implicaciones fisiopatológicas (I)

IntroductionMany publications consider that Alzheimer's disease (AD) is exclusive to the human species, and that no other animal species suffers from the disease. However, various studies have shown that some species can present with some of the defining characteristics of the human disease, including both neuropathological changes and cognitive-behavioural symptoms. DevelopmentIn this work, the results published (PubMed) on senile brain changes in non-human primates of different degrees of evolution, are reviewed. The neuropathological changes associated with the accumulation of amyloid or highly phosphorylated tau protein are rare outside the primate order, but in all the sub-orders, families, genera and species of non-human primates that have been studied, some senile individuals have shown amyloid accumulation in the brain. In fact, in some species the presence of these deposits in senility is constant. Changes related to the accumulation of tau protein are always of very little significance, and have been detected only in some non-human primate species, both little evolved and highly evolved. In different species of non-human primates, some types of cognitive-behavioural changes are more common in some senile individuals when compared with both normal adult individuals and other senile individuals of the species. The importance of determining the longevity of the species in different habitats (natural habitats, new habitats, semi-captivity, captivity) is stressed in these studies. ConclusionsMorphological, histochemical and cognitive-behavioural features similar to those observed in elderly humans are present in senile non-human primates. Moreover, other characteristics seen in non-human primates could be indicative of a pathological «Alzheimer type» ageing.

Vulnerability of small and medium-sized prey mammals in relation to their habitat preferences, age classes and locomotion types in the temperate Monte Desert, Argentina

In this study we examined predation by small felids upon small and medium-sized prey mammals in the central region of the Monte Desert. We analyzed the degree of vulnerability of prey mammals in relation to their habitat use patterns, modes of locomotion and age classes. Medium and small rodents were the predominant prey in the diet of small cats. The most consumed small mammal was Akodon molinae, which inhabits areas of dense cover, while species occurring in open habitats such as Eligmodontia typus were less consumed. Among medium-sized mammals, Galea leucoblephara that depends on patches with high plant cover for refuge was more consumed than Microcavia australis that lives in colonies and displays a complex set of antipredator strategies. Prey selectivity on small rodents showed that E. typus, which uses bipedal locomotion and an erratic escape behaviour, was consumed in greater proportion than its availability. We suggest that although its specialized locomotory mode would diminish predator attacks, its preference for open habitats would increase the probability of predator–prey encounter. Consumption of small mammals focuses mostly on adult individuals. However, we found a significant consumption of senile individuals of A. molinae, which points out that vulnerability tends to be high towards the age of maturity in this species.

Changes in the structure of a savanna forest over a six-year period in the Amazon-Cerrado transition, Mato Grosso state, Brazil

Abstract Vegetation changes in transition zones are still poorly studied. Changes in the vegetation structure of a savanna forest (cerradão) were assessed in the Amazon-Cerrado transition (14º42'2.3"S; 52º21'2.6"W), eastern Mato Grosso, within a period of six years (2002, 2005 and 2008). In 2002, fifty plots of 10 × 10 m were set up, where all trees with DSH30 ≥ 5 cm were measured; in 2005 and 2008 the plots were re-inventoried. In 2008, 84 species from 70 genera and 37 families were sampled; absolute density was 1,998 individuals/ha and basal area was 25.95 m2.ha-1. On the one hand, the absolute density of live individuals decreased from 2005 to 2008 (2,066 individuals/ha); on the other hand, the basal area increased in 2008 compared to 2005 (23.56 m2.ha-1) and 2002 (1,884 individuals/ha and 21.38 m2.ha-1). The species with the highest importance value in the period were Hirtella glandulosa, Tachigali vulgaris and Xylopia aromatica. Except for these three species, all other species underwent hierarchic changes in the importance value, indicating that most species frequently alternate. Community structure exhibited changes throughout the period; hence, we suggest investigations on the role of T. vulgaris in these changes, since environmental conditions caused by gap opening from the fall of senile individuals of this pioneer species with a short life cycle may contribute to community dynamics.

Dendritic Pathology and Spinal Loss in the Visual Cortex in Alzheimer's Disease: A Golgi Study in Pathology

ABSTRACTAlzheimer's disease is a neurodegenerative disorder characterized by progressive decline in memory, loss of professional skills, impairment of judgement and behavior, and decline in social performances. In terms of neuropathology, the morphological hallmarks of the disease are the accumulation of alpha–beta peptide and the neurofibrillary degeneration, associated with synaptic alterations, involving mostly the dendritic spines. This study is based on the morphological analysis of 10 brains, 5 of which were obtained from patients who suffered from Alzheimer's disease and 5 from nondemented senile individuals used as control group. The segments taken in major from the occipital lobe were studied with the use of Golgi method, as well as Gallyas’ and Bielschowski’ s staining methods. In most of the pyramidal cells in the affected brains, there seems to be important spine loss and extensive dendrite pathology. Apical dendrites are distorted and tortuous. Horizontal dendritic arborization is severely decreased leading to an amputated, bell-shaped cell soma. Senile plaques have been often revealed, and neurofibrillary changes have also been noticed.

Changes in Apoptosis and Cell Proliferation in Human Pineal Gland during Aging

Immunohistochemical analysis of the expression of proapoptotic protein P53 and proliferation protein Ki-67 in human pineal gland showed that in people over 60 years pinealocyte proliferation is virtually absent. Moreover, pinealocyte apoptosis is more pronounced in elderly, whereas in senile and long-living individuals its intensity decreases.

Reactive hypertrophy of synaptic varicosities within the hippocampus of prion-infected mice

Prion diseases are characteristically accompanied by extensive synaptic pathology that can occur during the preclinical phase of the disease and, in animal models, correlates with the first decline of hippocampus-dependent cognitive functions. This pathology is defined by abnormally shaped synapses in which the postsynaptic membrane modifies its curvature and potentially engulfs the juxtaposed presynaptic membrane. Using the intrahippocampally injected ME7 prion model, we further detailed the structural alterations of the population of ostensibly intact synaptic compartments within the hippocampus during this period of extensive synaptic loss. A disease stage-dependent increase in the average PSD (postsynaptic density) area, the average length of the active zone and the average number of synaptic vesicles indicated that the synapses that were visualized as the animal progressed to end-stage disease were undergoing hypertrophy. Similar findings in samples from AD (Alzheimer's disease) patients, aged and senile individuals, and animal models of neurodegenerative diseases suggest synaptic swelling as synaptic loss is initiated and/or compensatory reaction to counteract the synaptic loss.

Microdesgaste dentário em Procyon cancrivorus (Cuvier, 1798) (Mammalia, Procyonidae)

For this study, the Procyon cancrivorus m1, m2, PM4 and M1 teeth were analyzed by scanning electron microscopy in order to observe dental microwear patterns. Tooth of subadult, adult and senile individuals were studied. The results showed different microwear signs with pits and cross scratches abundance. The combination of pits and cross scratches suggests a microwear pattern related to omnivorous diet. The dental microwear may become a useful tool for the species food web analyses and assist the studies about diet

Value of waist circumference, body mass index and hyperinsulinaemia in identifying metabolic syndrome

To investigate the significance of waist circumference (WC), body mass index (BMI) and hyperinsulinaemia A (HIns) in evaluating metabolic syndrome (MS). Clinical data from middle-aged and senile individuals (middle-senile group) who received glucose tolerance test after diabetes mellitus screening and a group of subjects who received annual oral glucose tolerance test (OGTT) for diabetes mellitus screening (adult group) were collected. Data were collected by use of special messengers, input into a computer data base and analyzed using SAS 5.0 software by expert staff. Abnormal WC and BMI were determined according to International Diabetes Federation (IDF) and Chinese Diabetes Society (CDS) criteria. HIns was ascertained if fasting insulin (FIns) ⩾ 15 mU/L, and/or 2-hour insulin after a glucose challenge was (2hPIns) ⩾ 80 mU/L. Abnormalities in WC, BMI and HIns were all found to be risk factors for abnormal glucose metabolism, hypertension and dyslipidemia. In the middle-senile group, the abnormality rate of WC and HIns as well as the overall insulin level were significantly higher than those in the adult group. The abnormality rate of BMI was higher in the adult group, and HIns was mostly seen in impaired glucose test (IGT) and normal glucose test (NGT). The concordance rate of WC and BMI diagnostic criteria for evaluating obesity in the middle-senile and adult groups were 77.5% and 74.3%, respectively. When only the WC criterion was used for evaluating the existence of insulin resistance, there was a 28.2%missed diagnosis rate for MS patients. WC, BMI and HIns were all risk factors for abnormal glucose metabolism, hypertension and dyslipidemia. There was differing prevalence in the different populations. The combination of WC, BMI and HIns might be more helpful in identifying MS at early stage.

Morfometria do miocárdio humano em indivíduos senis

To carry out a quantitative assessment in human myocardium cells of senile individuals, in right, left and septal ventricular regions. Five hearts from corpses of individuals without heart diseases, of both sexes, with age between 67 and 87 years old were used. The following parameters were assessed: myocyte unit cross section area (myoc. a(o)); myocyte unit perimeter length (myoc. l(o)); myocyte unit volume (myoc. v(o)); myocyte volumetric density (myoc. V(v)); number of myocytes per volume unit (Nmm 3myoc.). The t-test of Student was used in statistic analysis. The analysis of differences (p < 0.05) among right (RV), left (LV) and septal (S) ventricular regions of human heart showed that myoc. a(o) values were lower in RV (1.51 +/- 0.10 microm2) and in S (1.55 +/- 0.07 microm2) in relation to LV (1.84 +/- 0.24 microm2). Values of myoc. l(o) were also shown lower in S (5.11 +/- 0.46 microm) comparing to LV (6.2 +/- 0.97 microm). Likewise, myoc. v(o) and myoc. V(v) showed lower values in RV (88.75 +/- 25.37 microm3; 0.39 +/- 0.03%) in relation to LV (122.41 +/- 16.31 microm3; 0.41 +/- 0.01%). Results obtained show that there may be changes in dimensions of left ventricular wall myocyte cell during senescent stage. However, those differences are subtle and seem to mean the adjustment of tissue to functional changes that install along life.

Effects of age on elements of insulin-signaling pathway in central nervous system of rats.

Insulin resistance is known to play a pivotal role in type 2 diabetes. Senile individuals, besides being prone to insulin resistance and, consequently, to type 2 diabetes, manifest diseases of the central nervous system (CNS) that may be influenced by disturbances of insulin signaling in the brain, such as memory impairment, Parkinson disease, and Alzheimer disease. We investigated the expression and response to insulin of elements involved in the insulin-signaling pathway in the forebrain cortex and cerebellum of rats ages 1 d to 60 wk. The protein content of insulin receptors and SRC homology adaptor protein (SHC) did not change significantly along the time frame analyzed. However, insulin-induced tyrosine phosphorylation of the insulin receptor and SHC, and the association of SHC/growth factor receptor binding protein-2 (GRB2) decreased significantly from d 1 to wk 60 of life in both types of tissues. Moreover, the expression of SH protein tyrosine phosphatase-2 (SHP2), a tyrosine phosphatase involved in insulin signal transduction and regulation of the insulin signal, decreased significantly with age progression, in both the forebrain cortex and the cerebellum of rats. Thus, elements involved in the insulin-signaling pathway are regulated at the expression and/or functional level in the CNS, and this regulation may play a role in insulin resistance in the brain.

Gallbladder hypomotility (GBH) is not essential for the development of gallstones (GS) in senile individuals

Gallbladder hypomotility (GBH) is not essential for the development of gallstones (GS) in senile individuals

Life Cycle of Paramecium bursaria Syngen 1 in Nature

ABSTRACT. Studies were completed on the natural population density of Paramecium bursaria syngen 1 and on the life cycle stages to which the individuals belonged. Green paramecia were collected from two streams once every 20 days for over one year: 413 individuals on 26 collection dates in Mikumarikyo stream and 83 individuals on 23 collection dates in Momijidani‐gawa stream. Individuals in nature did not maintain at a steady density but fluctuated greatly depending on the month. It seems that conjugation occurred from April to June in the Mikumarikyo stream and from May to June in the Momijidani‐gawa stream. The appearance of individuals with mating ability might be related closely to increasing population so that sexual reproduction probably occurred near the peak of the population density. The 413 individuals from Mikumarikyo stream were examined to determine their position within the life cycle; 309 (74%) were immature, 55 (13%) were adolescent, and 49 (12%) were mature. No senile individuals were observed. The fraction of individuals with mating ability was generally less than 30% at any collection. Four mating types were observed occurring with about equal frequencies in mature individuals. The results show the frequencies of the recessive genes for mating types (a and b) are higher than for dominant genes (A and B). Of 83 individuals from Momijidani‐gawa stream, 44 (52%) were immature, 21 (25%) were adolescent, and 18 (21%) were mature. Again, no senile individuals were observed. Because only two mating types were found, II and III (genotypes aaB‐ and aabb), it seems possible that the dominant gene A was rare or absent in the Momijidani‐gawa population.

Death, Dying, and the Biological Revolution: Our Last Quest For Responsibility by Robert M. Veatch

BOOK REVIEWS 155 Death, Dying, and the Biological Revolution: Our Last Quest For Responsibility . By RoBERT M. VEATCH. New Haven and London: Yale University Press, 1976. Pp. 323 including index and bibliography. This book's three major themes are: (I) establishing the category difference between technical questions of medical feasibility and ethical questions of moral legitimacy; (2) defining ' death ' and ' dying ' so as to elucidate the difference between medical treatments which support life and those which "prolong dying "; and (3) showing the difficulty of articulating a public policy-not to mention an established medical ethic-about the dying and the recently dead in a society so pluralistic as almost to be antinomian. Veatch knows that these are questions of the first complexity, and avoids stating his views as dogma, occasionally leaving his own opinion on the issues unclear. Properly, he also avoids mechanically spinning out theorems based on axioms of ethics. The book's greatest value is the critical sensitivity with which it exposes and dissects the levels of these problems. Relations between ethics, policy, and medical feasibility are often uneasy, and Veatch appreciates this fact. He is also well-informed concerning both recent law on the topics and the current state of the medical art. The most philosophically interesting section is Veatch's analysis of four competing definitions of ' death '. His novel position is that it is as morally offensive to treat dead individuals as living as it traditionally has been to treat the living as though they were dead. His choice of definition is the " irreversible loss of capacity for social interaction "; his justification for this choice, in contrast to the " capacity for bodily integration ", is the neurologic fact that the autonomic, medullary controls for fluid circulation and for some reflexes (e.g. yawning) can persist in a person whose EEG is irreversibly isoelectric for what Veatch calls the higher functions, such as thought, reason, and emotion. (His note on " permanent back ward psychotics or senile individuals " needs amplification, though, since they aren't brain stem cases and equally clearly have no capacity for social interaction.) His meticulous analysis of the medical and legal options in defining death supports his thesis, put rhetorically: "How could medical research possibly discover that death should be pronounced when brain function rather than heart function has stopped irreversibly? " (Italics added). The book's focus-especially seen in chapters 3, 4, and 5-is on the results of this definition of death in the realm of public policy. He begins with an exploration of some of the concurrent problems: active vs. passive euthanasia, " slippery slope " consequences, and " extraordinary " medical intervention. His decisive move is to recast all these arguments from the perspective of the patient who acts as agent in his own behalf. "... To view the moral 156 BOOK REVIEWS issue from the standpoint of rights and obligations of the patients rather than from the moral alternatives of physicians ... changes the character of the discussion. The consequences are predictable. The patient (or his agent) should decide what interventions are acceptable, whether extended respiratory support for a cerebrally dead patient is "extraordinary", and so on. Veatch is in the " reasonable man " camp with this sort of guideline, and as many reasonable man theorists are, he is compelled quickly to admit legal recourse in deciding" reasonableness " (and, similarly, " grave burdensomeness " of treatments). Given the spectrum of judicial good sense and lack of it which Veatch recounts, one wonders how the practical consequences of his principle will improve on current policy. He reviews the refusal-of-treatment cases, including the Jehovah's Witness blood transfusion cases and the Down's syndrome infants with intestinal blockages, and discusses the Quinlan matter most astutely, concluding, in parallel with the New Jersey Supreme Court, that "refusal of death-prolonging treatments should be seen as radically different from and normally more reasonable than refusal of lifesaving treatments." (As noted above, Veatch appreciates that " gravely burdensome treatment " has almost as much of a subjective element as does the "reasonableness " of a refusal.) While Veatch's section on definitions of death suggests that patients choose between cardiopulmonary, bodily-integrative, and social-competence definitions , but not outside these, no such guide for " reasonableness...

Internal Fixation Versus Nontreatment of Hip Fractures in Senile Patients

Institutionalized senile patients with hip fractures have a high mortality regardless of whether treatment consists of internal stabilization or is non-operative. In an effort to select the best therapeutic approach in this type of patient, 150 patients were examined in 3 comparable groups. In the first group of 50 patients treatment consisted of surgical stabilization of the fracture. In the second group of 45 patients treatment was non-operative; mortality in these 2 groups was over 50% at the end of 16 weeks. In an effort to improve this degree of risk we transferred 53 patients from the psychiatric hospital to a general hospital for prompt internal stabilization of the hip fractures. There was a striking decrease in mortality to 28% in the third group. We have concluded that under optimal conditions, prompt surgical stabilization of hip fractures in elderly senile individuals offers them the best opportunity of surviving the injury and is preferable to nontreatment.

The Consequences of Predation and Competition upon the Demography of Gambusia manni (Pisces: Poeciliidae)

Krumholz (1963) proposed that predation and competition affected the survivorship and fertility schedules of Gambusia manni at Bimini, Bahamas. He showed that in predator exposed populations the sex ratio was lower, no senile individuals were present, the number of offspring per brood was higher and that in males there was a definite shift in the size at maturity. He was unable to explain the shift in the size at maturity by use of the predation and competition hypothesis. New information on the forces affecting maturity in the poeciliid fishes (Borowsky, 1973) is used to demonstrate that this unexplained demographic variable can be plausibly explained by the predation-competition hypothesis. I demonstrate that the size at maturity is functionally related to the presence of an adult male and that maturation is delayed until a juvenile exceeds the adult male in size.

The development of thyroid neoplasia in old age in the amazon molly, Poecilia formosa

In a previous paper we have described the appearance of a thyrotrophin sensitive thyroid neoplasm in an few senile individuals from a laboratory population of guppies, Lebistes reticulatus (Peters). Material has now been examined from the closely related species, Poecilia formosa, the Amazon molly, in which the incidence of thyroid neoplasms in the senile fish of our clones approaches 100%. The spontaneous growth seen in the old mollies was large, occupying much of the pharyngeal region. It was formed of three zones; at the center were inactive follicles with flattened epithelial cells, enclosing a dense, uneroded colloid. Peripherally, there was an area which microfollicles predominated and, the follicular epithelial cells frequently were swollen and balloon-like. The outermost area of the growth contained many afollicular groups of epithelial cells, lying amongst a great deal of loose connective tissue. The thyroid tissue was invasive, destroying muscle and bone. We have suggested that the spontaneous thyroid neoplasia in old P. formosa and L. reticulatus arise in a similar way. They develop as a result of the inability of the aging thyroid to respond to thyrotrophic hormone. Under continued pituitary stimulation the thyroid cells greatly proliferate and hypertrophy, and form a neoplasia. The appearance is described of massive thyroid growths which were experimentally induced by the injection into young mollies of cells with damaged DNA. There were striking differences between the induced and the spontaneous thyroid growths. The neoplasia of old fish was highly variable in structure, but the induced neoplasia had a regular appearance. Neoplastic tissue closely resembled normal thyroid tissue—but the growth was exuberant and highly invasive. We suggest that the differences between the neoplasm of old age and the induced neoplasm may reflect a different hormonal status.

Lipoid Pneumonia Caused By Methenamine Mandelate Suspension

Two senile individuals with dysphagia developed lipoid pneumonia subsequent to the administration of methenamine mandelate (Mandelamine) suspension, 250 mg methenamine mandelate/teaspoon. Methenamine suspension forte (double strength) contains oil of sesame (USP) and hydrogenated castor oil. Methenamine mandelate suspension contains these two ingredients plus champagne cider oil. Methenamine mandelate should be given to dysphagic patients in the form of crushed tablets mixed with semisolid food.

Identification of the cells in the adenohypophysis of the puffer, Fugu niphobles (Jordan et Snyder).

In order to elucidate the details of the hypophysis of the puffer, Fugu niphobles, histological and cytological studies were performed on specimens collected at rocky beaches and specimens kept experimentally in dilute sea water. This species is known well as a marine fish by having a peculiar spawning habit and ascending behavior toward the river. The neurohypophysial ramifications penetrate extensively into the entire adenohypophysis, especially into the pars distalis. The adenohypophysis is divisible into three portions: the rostral and proximal pars distalis, and pars intermedia. The rostral pars distalis consists mainly of three glandular cells. They are lead hematoxylin (PbH)-positive acidophil (A1 cell), aldehyde fuchsin (AF)-positive and periodic acid Schiff (PAS) reaction-positive basophil (B1 cell), and the small chromophobe (C cell) cells. The proximal pars distalis includes two cell types: the dorsally shifted orangenophil (A2 cell) and more ventrally shifted, AF- and PAS-positive polyhedral cell (B2 cell). There are two types of cells in the pars intermedia: they are larger, PbH-positive acidophil (I1 cell) and smaller, weak PAS-positive chromophobe (I2 cell) cells. Two other strange cell types are also encountered in the adenohypophysis of some of the senile individuals. The C cells of the fish kept in 1/6 dilute sea water exhibit a marked hypertrophy in comparison with those of the fish kept in normal sea water. Some of the A1 cells are also activated by dilute salinity.

Effects of sacbrood virus on adult honey‐bees

SUMMARYMuch sacbrood virus accumulates in the brains of infected bees, especially of drones, without causing symptoms. However, infected individuals fly earlier in life than healthy bees and most infected foragers fail to collect pollen, as do bees briefly anaesthetized with CO2. The few infected bees that gather pollen contaminate their loads with much sacbrood virus. Infection does not shorten the lives of drones, or of workers that have been deprived of pollen, but it much shortens the prolonged lives of workers that have eaten pollen. Infected workers, healthy workers deprived of pollen, and senile individuals are unable to maintain the usual metabolic rates of bees at temperatures below 35oC, or to resist chilling.