Relationship between megadose vitamin supplementation and immunological function in a healthy elderly population.

We studied the immunological effects of 'megadose' vitamin or mineral supplementation by comparing the immunological functions of healthy elderly subjects taking large amounts of specific nutrients to similar subjects not on supplements. There was a non-significant trend for those subjects taking megadoses of vitamin C to have increased cell-mediated immune responses as measured in vivo by skin test reactivity but not by in vitro mitogen responses. In addition, subjects taking megadoses of vitamin E or any of several B vitamins (B1, B2, B6, folate and niacin) had lower absolute circulating lymphocyte counts than did the rest of the population. The relative lack of effect of megadose vitamins on immunological function in this population compared to reports of short term trials of mega nutrients raises the possibility that some of the previously reported immuno-enhancing properties of megadose vitamins may be due to a non-specific adjuvant effect that disappears with time.     

烧伤的流行病学、人口统计学及结局特点

老年人的群体在不断扩大，而他们烧伤的发病率和死亡率都要比年轻人高。最近的一项病例回顾研究分析了一家烧伤中心7年来住院患者的资料，结果显示，1557位住院患者中有221位（11％）年龄在59岁以上（含59岁）。其中有97位（44％）是女性，反映出老年患者中女性比例较高。     

Lethal infection by Bordetella pertussis mutants in the infant mouse model.

Different aspects of lethal infection of infant mice with Bordetella pertussis were examined. Mutants deficient in vir-regulated genes were tested for the ability to cause a lethal infection in the infant mouse model. Adenylate cyclase toxin-hemolysin and pertussis toxin were required to cause a lethal infection at low doses. Mixed infection caused by challenging the mice with an equal number of pertussis toxin and adenylate cyclase toxin-hemolysin mutants at a dose at which neither alone was lethal was also unable to cause a lethal infection. Production of the filamentous hemagglutinin and the dermonecrotic toxin was not required to cause a lethal infection. Nine other mutants in vir-regulated genes whose phenotypes have yet to be determined were also tested. Only two of these mutants were impaired in the ability to cause a lethal infection. Expression of fimbriae does not appear to affect the dose required to cause a lethal infection; however, fimbrial expression was correlated with the later stages of a nonlethal, persistent infection. Growth of the bacteria in MgSO4, a condition which reversibly suppresses expression of the genes required for virulence, did not alter the ability of the bacteria to cause a lethal infection. Auxotrophic mutants deficient in leucine biosynthesis were as virulent as the parental strain; however, mutants deficient in methionine biosynthesis were less virulent. A B. parapertussis strain was much less effective in promoting a lethal infection than any of the wild-type B. pertussis strains examined. A persistent infection in the lungs was observed for weeks after challenge for mice given a sublethal dose of B. pertussis, and transmission from infected infants to the mother was never observed.     

Comorbidity of asthma and anxiety and depression in Puerto Rican children

Studies have reported that childhood asthma is associated with internalizing disorders, but most of these studies have used global measures of depressive and anxiety symptoms. The Diagnostic Interview Schedule for Children was administered to a group of 1891 youth ages 4 to 17 and their caregivers in Puerto Rico to determine DSM-IV symptoms and diagnoses. Asthma diagnosis and having had an asthma attack were assessed by parental report. A diagnosis of asthma was associated with having any depressive disorder and one symptom of separation anxiety. An asthma attack was associated with any depressive disorder and any anxiety disorder and, more specifically, with separation anxiety disorder, major depressive disorder, and symptoms of depression, separation anxiety, and generalized anxiety. Possible explanations for the findings are discussed.     

The pattern of function-related regional cerebral blood flow investigated by single photon emission tomography with 99mTc-HMPAO in patients with presenile Alzheimer's disease and Korsakoff's psychosis

Single photon emission tomography (SPET) with the lipophilic blood flow marker 99mTc-hexamethyl propyleneamine oxime (99mTc-HMPAO) has been used to determine regional uptake of radiolabel into brain regions of patients with presenile Alzheimer's disease and Korsakoff's psychosis, and age-matched controls. Using occipital cortical uptake as reference area, the pattern of relative regional cerebral blood flow (rCBF) was determined in other cortical areas and basal ganglia. In Alzheimer's disease, reduction in rCBF occurred most strikingly in posterior temporal and parietal areas. By contrast, in Korsakoff's psychosis, posterior temporal rCBF was maintained, although there was a trend to reduced tracer uptake in other cortical areas. These impairments of flow were correlated with impairments of neuropsychological function. In Alzheimer's disease, left posterior temporal and left parietal regions in particular showed rCBF to be strongly correlated with most aspects of cognitive function. In Korsakoff's psychosis, however, impaired flow in frontal regions was correlated with impaired performance on tests of memory and orientation. The findings in Alzheimer's disease show quantitative parallels with those from studies using Positron Emission Tomography (PET), and extend our understanding of the relationship between cognition and regional brain function in dementia. The findings in Korsakoff's psychosis offer the first direct evidence linking frontal lobe dysfunction with the cognitive impairment seen in the disorder.     

New mutations in MID1 provide support for loss of function as the cause of X-linked Opitz syndrome

Opitz syndrome (OS) is a genetically heterogeneous malformation disorder. Patients with OS may present with a variable array of malformations that are indicative of a disturbance of the primary midline developmental field. Mutations in the C-terminal half of MID1, an RBCC (RING, B-box and coiled-coil) protein, have recently been shown to underlie the X-linked form of OS. Here we show that the MID1 gene spans at least 400 kb, almost twice the distance originally reported and has a minimum of six mRNA isoforms as a result of the alternative use of 5' untranslated exons. In addition, our detailed mutational analysis of MID1 in a cohort of 15 patients with OS has resulted in the identification of seven novel mutations, two of which disrupt the N-terminus of the protein. The most severe of these (E115X) is predicted to truncate the protein before the B-box motifs. In a separate patient, a missense change (L626P) was found that also represents the most C-terminal alteration reported to date. As noted with other C-terminal mutations, GFP fusion constructs demonstrated that the L626P mutant formed cytoplasmic clumps in contrast to the microtubular distribution seen with the wild-type sequence. Notably, however, both N-terminal mutants showed no evidence of cytoplasmic aggregation, inferring that this feature is not pathognomonic for X-linked OS. These new data and the finding of linkage to MID1 in the absence of a demonstrable open reading frame mutation in a further family support the conclusion that X-linked OS results from loss of function of MID1.     

An enzyme-linked immunosorbent assay (ELISA) for the major crustacean allergen, tropomyosin, in food

Shellfish are a common cause of food reactions in hypersensitive individuals and are among the eight foods that account for over 90% of food allergies. At present, the only way to prevent these serious consequences of food allergies is to avoid the foods that trigger the reactions. A sandwich-ELISA kit has been developed for the detection of crustacean meat in food, based on the major heat-stable shellfish allergen, tropomyosin. Tropomyosin was purified from whole prawn (Penaeus latisulcatus) and used to immunize rabbits after confirming its identity by MALDI-TOF MS. A sandwich-ELISA based on the rabbit antibodies takes less than 2 h to perform, including the food extraction, and has a detection limit of 1 ppm crustacean (prawn, lobster), without detectable cross-reactivity with fish or mammalian meat.     

Construction of peptoliposomes for the incorporation of nutrient lipid supplements in insect cell culture media

Summary Nutrient liposomes that incorporate peptones instead of serum proteins can be used for the lipid supplementation of insect cells in lieu of or in addition to vertebrate serum to enhance the growth or differentiation of specific insect cell types in culture. The technique described here for the preparation of nutrient peptoliposomes involves the combination of both natural and synthetic phosphatidyl cholines (containing essential polyunsaturated fatty acids) with appropriate sterols. These are protected against premature oxidation by antioxidants (glutathione, alanine, protein hydrolysates) and antioxidant synergists (citrate, ascorbate, plus other amino acids) in the basal tissue culture medium as well as in the liposomal preparation itself (alphatocopherol acetate and protein hydrolysates). The lipid components are filter sterilized in chloroform and then dried before aqueous sonication, allowing the subsequent formation of a random array of unsized uni- and multilamellar liposomes, which are suitable as direct suppliers of lipid nutrients as well as nutrient carriers for lipid-soluble supplements.     

Fertilization and early embryology: Influence of maternal age on meiotic spindle assembly oocytes from naturally cycling women

To examine the effects of maternal ageing on the meiotic apparatus,we obtained oocytes from naturally cyding women in two age groups,including younger (aged 20–25 years) and older (aged 40–45years) women. Using high- resolution confocal microscopy weobtained a detailed picture of the meiotic spindle and chromosomeplacement during various phases of meiosls. Our data revealedthat the meiotic spindle in older women is frequently abnormal,both with regard to chromosome alignment and the micro- tubulematrix that comprise the meiotic spindle. The spindle in 79%of the oocytes from the older group exhibited abnormal tubulinplacement and one or more chromosomes were displaced from themetaphase plate during the second meiotic division. In contrast,only 17% of the oocytes from the younger age group exhibitedaneuploid conditions. The majority of eggs from this group possesseda well ordered, meiotlc spindle containing chromosomes thatwere fully aligned within a distinct metaphase plate in thespindle. Chromosome management during meiosis is directed bymicrotubule assembly within the spindle. These data suggestthat the regulatory mechanisms responsible for assembly of themeiotic spindle are significantly altered in older women, leadingto the high prevalence of aneuploidy.     

Affective and Behavioral Stress Outcomes in Alzheimer's Caregivers

Few investigations have looked at behavioral stress outcomes in Alzheimer's caregivers. This study documented concentration deficits to examine behavioral outcomes of stress in 33 Alzheimer's Disease (AD) caregivers and in 33 age-, sex-, and race-matched controls. As hypothesized, caregivers showed less persistence than controls in solving problems from a standard test of problem-solving ability. In addition, caregivers tended to make more errors than controls on a standard proofreading task ( p < .09). In AD caregivers, cognitive deficits (represented by lower scores on problem-solving and concentration tasks) may be representative of a broader deficit in concentration that impairs the ability of caregivers to provide for their own needs and the needs of the family member for whom they are caring.