Long-lived alphaMUPA transgenic mice show reduced SOD2 expression, enhanced apoptosis and reduced susceptibility to the carcinogen dimethylhydrazine

Calorie restriction (CR) extends the life span of various species through mechanisms that are as yet unclear. Recently, we have reported that mitochondrion-mediated apoptosis was enhanced in alphaMUPA transgenic mice that spontaneously eat less and live longer compared with their wild-type (WT) control mice. To understand the molecular mechanisms underlying the increased apoptosis, we compared alphaMUPA and WT mice for parameters associated with SOD2 (MnSOD), a mitochondrial antioxidant enzyme that converts superoxide radicals into H(2)O(2) and is also known to inhibit apoptosis. The SOD2-related parameters included the levels of SOD2 mRNA, immunoreactivity and enzymatic activity in the liver, lipid oxidation and aconitase activity in isolated liver mitochondria, and the sensitivity of the mice to paraquat, an agent that elicits oxidative stress. In addition, we compared the mice for the levels of SOD2 mRNA after treatment with bacterial lipopolysaccharides (LPS), and for the DNA binding activity of NFkappaB as a marker for the inflammatory state. We extended SOD2 determination to the colon, where we also examined the formation of pre-neoplastic aberrant crypt foci (ACF) following treatment with dimethylhydrazine (DMH), a colonic organotypic carcinogen. Overall, alphaMUPA mice showed reduced basal levels of SOD2 gene expression and activity concomitantly with reduced lipid oxidation, increased aconitase activity and enhanced paraquat sensitivity, while maintaining the capacity to produce high levels of SOD2 in response to the inflammatory stimulus. alphaMUPA mice also showed increased resistance to DMH-induced pre-neoplasia. Collectively, these data are consistent with a model, in which an optimal fine-tuning of SOD2 throughout a long-term regimen of reduced eating could contribute to longevity, at least in the alphaMUPA mice.     

The effects of subdiaphragmatic vagotomy on circadian corticosterone rhythmicity in rats with continuous or restricted food access

Plasma corticosteroid circadian periodicity was determined in three groups of individual adult male rats. Categories were: postsubdiaphragmatic vagotomy, sham-operated, and controls. Blood was sampled every 4 hours over a 48-hour period with ad lib feeding and after a 13-day period on daytime (0930–1330) restriction of food and water availability. Plasma corticosterone circadian periodicity was normal under ad lib conditions in control, sham-operated, and vagotomized animals. Under food-restricted conditions, both the sham-operated and vagotomized animals exhibited the 12-hour shift in the circadian peak of plasma corticosterone levels that we have previously described in normal animals under such conditions. There were no differences between groups in the total amount of food and water consumed or the percentage of nocturnal food intake on an ad lib feeding schedule. Both vagotomized and sham-operated animals manifested reductions in food intake under conditions of food restriction, although vagotomized consumed less than sham-operated animals. The present data indicate that an intact vagus nerve is not necessary for the establishment of circadian periodicity of plasma corticosterone levels or the shift in the periodicity of corticosteroid secretion produced by a restricted feeding regimen.     

Effect of histamine infusion on circulating methionine-enkephalin and catecholamine concentrations

In 5 normal adult men, histamine was infused i.v. for 5 min at 20 micrograms/kg/h and at 80 micrograms/kg/h on two occasions one week apart. Diastolic blood pressure fell and heart rate, plasma adrenaline and noradrenaline all rose in a dose-dependent manner, but plasma methionine-enkephalin (Met-Enk) concentrations were unchanged. These results indicate that while Met-Enk may be co-stored with catecholamines (CAs) in the adrenal medulla in at least this paradigm, circulating concentrations of CAs may be altered without similar changes in plasma Met-Enk immunoreactivity.     

涎腺腺样囊性癌高、低转移细胞系基因表达谱及基质金属蛋白酶表达差异

目的筛选与涎腺腺样囊性癌转移相关的候选基因，并对其中的候选基因进行初步的验证。方法用限制片段差异显示PCR技术（restriction fragments differential display PCR, RFDD-PCR）建立涎腺腺样囊性癌高、低转移细胞株（ACC-M、ACC-2）的表达谱。对两个表达谱的片段进行比较，通过生物信息学的分析，初步筛选出候选基因。用半定量逆转录PCR技术对筛选出的基因进行初步验证。结果RFDD-PCR方法共获得5420个基因片段，其中包含12个基质金属蛋白酶（matrix metalloproteinase，MMP）基因。半定量逆转录PCR方法发现MMP2、MMP7、MMP9、MMP14、MMP15、MMP24在ACC-M和ACC-2中的表达存在明显差异。结论构建了ACC-M和ACC-2细胞株的表达谱，为寻找目的基因奠定了基础。发现MMP2、MMP7、MMP9和MMP15与涎腺腺样囊性癌的发生、发展、转移有关，不同肿瘤细胞的转移能力可能与不同的MMPs家族基因相关。     

Multipoint linkage mapping of the Xq25-q26 region in a family affected by the X-linked lymphoproliferative syndrome

We have performed, in a large Swiss family, a study of linkage between various DNA markers in the Xq24-27 region and the locus for the X-linked lymphoproliferative syndrome (XLP). Our results indicated that the marker DXS37 in Xq25-q26 is genetically linked to the XLP syndrome. The multipoint linkage analysis showed that the disease locus is distal to DXS11, but proximal to the hypoxanthine phosphoribosyl-transferase gene (HPRT).     

The cholesteryl ester transfer protein (CETP) locus as a candidate gene in abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is a relatively common disease of the elderly presenting as progressive dilatation of the abdominal aorta. The condition shows a pronounced tendency to cluster in families, indicating a genetic component in the disease aetiology. We have screened the cholesteryl ester transfer protein (CETP) gene, which has been proposed as a candidate gene in AAA, by means of SSCP, DNA sequencing and restriction analysis in a cohort of patients with AAA and a matching control group drawn from the Irish population. The analysis has demonstrated sequence variation at four sites in the CETP gene: an A-T transversion in exon 9 (producing a Lys309-Stop codon substitution), a G-A transition in exon 14 (producing a conservative Va1421-Ile substitution), a C-T transition in intron 12 and a G-A transition in intron 15. None of the last three sites corresponded with sites of functional significance in the protein, suggesting that this reflects neutral polymorphism at the CETP locus. Furthermore, the frequencies of these four polymorphisms in the AAA patient and control groups were not significantly different. These data therefore suggest that CETP may be excluded as a candidate gene in abdominal aortic aneurysm.     

Epidemiology of molluscum contagiosum using genetic analysis of the viral DNA

The molecular epidemiology of molluscum contagiosum virus (MCV) infections was investigated by restriction endonuclease analysis of the genomes of 222 separate isolates collected from 147 patients living in Germany (33 patients), Hong Kong (6 patients), and Scotland (108 patients). MCV type 1 (MCV-1) caused 96.6% of the infections, and MCV type 2 (MCV-2) caused 3.4%. However, isolates from four of the 142 MCV-1-infected patients and two of the five MCV-2-infected patients showed minor differences in their DNA restriction patterns because of the loss of a single or very few recognition sites for the enzymes used. No genome variations were detected amongst isolates collected from different sites or on several occasions from individual patients or from closely related patients. Southern blot hybridization revealed a high level of relatedness between MCV-1 and 2. No differences were seen in the appearance or anatomical localization of lesions caused by either virus type. In particular, there was no preferred genital localization for MCV-2 infections.     

Approximately 80% of Japanese osteoarthritic patients fall out of the safety range in restricted kinematically-aligned total knee arthroplasty in an analysis of preoperative long-leg radiograms

BackgroundRestricted kinematically-aligned total knee arthroplasty (KA-TKA) is a reasonable modification to avoid the alignment outlier that may cause implant failure. However, despite a noted high incidence of constitutional varus in Japanese individuals, there has been no investigation into how many knees require the restriction in restricted KA-TKA (RKA-TKA) among Japanese patients. Therefore, we conducted a study using preoperative long-leg radiograms.MethodsWe studied long-leg radiographs of 228 knees in 114 consecutive patients. The numbers of knees within the safety range and their corrective osteotomy angle in the restriction algorithms advocated by Almaawi et al. (2017) and MacDessi et al. (2020) were evaluated.ResultsAccording to the algorithms used by Almaawi et al. and MacDessi et al., out of 228 knees, 46 (20%) and 39 (17%) fell within the safety range, respectively. The mean correction angles of the hip-knee-ankle angle, lateral distal femoral angle and medial proximal tibial angle were 2.8 ± 3.4°, 0.4 ± 1.4° and 2.4 ± 2.8° in the algorithm used by Almaawi et al., while they were −4.9 ± 4.7°, 1.1 ± 2.5° and −6.0 ± 3.4° in the algorithm used by MacDessi et al. Most of the knees needed to be restricted in order to perform RKA-TKA, regardless of the algorithm used.ConclusionsBased on a preoperative analysis of long-leg radiograms in a Japanese population, most knees fall out of the safety range in RKA-TKA. Surgeons must consider whether to allow component outlier or to perform corrective osteotomy that likely requires soft tissue release.     

Behavioral and physiologic responses to caloric restriction in mice

The purpose of the review is to highlight the influences of ambient temperature (T(a)) and caloric restriction (CR) on metabolism, cardiovascular function and behavior in mice. Standard vivarium ambient temperatures (T(a)?23 degrees C) are a mild cold stress for mice requiring elevated metabolic rate and food intake. Increasing T(a) into the zone of thermoneutrality (TMN?29-33 degrees C) markedly reduces food intake, metabolic rate, heart rate (HR) and blood pressure in mice. Mice are members of a diverse, yet unique group of homeothermic animals that respond to thermal and energetic challenges by allowing body temperature (T(b)) to fall to less than 31 degrees C, a condition known as torpor. In mice housed at standard T(a), torpor is induced by a single night of fasting or a few days of CR. The mechanisms responsible for initiating torpor are related to reduced caloric availability, but do not require leptin. Mice housed at TMN and subjected to CR exhibit physiologic reductions in metabolic rate and HR, but do not appear to enter torpor. Finally, mice exhibit differential locomotor activity responses during CR that depends on T(a). At standard T(a), mice display increased light-phase home-cage activity with CR. This response is virtually eliminated when CR is performed at TMN. We suggest that researchers using mice to investigate energy homeostasis and cardiovascular physiology carefully consider the influence of T(a) on physiology and behavior.