Cdk12 maintains the integrity of adult axons by suppressing actin remodeling.

The role of cyclin-dependent kinases (CDKs) that are ubiquitously expressed in the adult nervous system remains unclear. Cdk12 is enriched in terminally differentiated neurons where its conical role in the cell cycle progression is redundant. We find that in adult neurons Cdk12 acts a negative regulator of actin formation, mitochondrial dynamics and neuronal physiology. Cdk12 maintains the size of the axon at sites proximal to the cell body through the transcription of homeostatic enzymes in the 1-carbon by folate pathway which utilize the amino acid homocysteine. Loss of Cdk12 leads to elevated homocysteine and in turn leads to uncontrolled F-actin formation and axonal swelling. Actin remodeling further induces Drp1-dependent fission of mitochondria and the breakdown of axon-soma filtration barrier allowing soma restricted cargos to enter the axon. We demonstrate that Cdk12 is also an essential gene for long-term neuronal survival and loss of this gene causes age-dependent neurodegeneration. Hyperhomocysteinemia, actin changes, and mitochondrial fragmentation are associated with several neurodegenerative conditions such as Alzheimer's disease and we provide a candidate molecular pathway to link together such pathological events.

Anal endosonography and fistulography for fistula-in-ano.

PURPOSE: In this study, a comparison was made of the accuracy and clinical usefulness of anal endosonography and fistulography in the preoperative classification of fistulas-in-ano. MATERIALS AND METHODS: A total of 113 patients with a clinical diagnosis of cryptoglandular fistula-in-ano who were awaiting surgery were included in this retrospective review. Patients were preoperatively investigated by anal endosonography and/or modified fistulography by inserting a Foley catheter into the rectum and a metal ring close to the anus. The catheter and ring served as radiopaque anal markers. Fistula classification obtained by the two diagnostic modalities was compared with surgical classification as the criterion standard. RESULTS: Endoanal ultrasound and fistulography identified 82.8% and 100% of primary tracks, 79% and 74.2% of internal openings, 98% and 91.8% of secondary tracks and 92.9% and 87.8% of abscesses, respectively. CONCLUSIONS: Anal endosonography and fistulography with radiopaque markers are important complements to surgical exploration for investigating anal sepsis and may be of value to the surgeon in planning a therapeutic strategy.

The retinoblastoma gene product in acute myeloid leukemia: a possible involvement in promyelocytic leukemia.

The retinoblastoma susceptibility gene in leukemia and lymphoma has been investigated using different approaches involving either gene or protein analysis. In this study, a novel method, which evaluates the functional status of the retinoblastoma gene product by a binding assay to an in vitro-translated viral oncoprotein, has been applied to leukemic cells from acute myeloid leukemia patients. One hundred twenty-two cases were considered, and 42 of them were also analyzed by Western blot. Results obtained with the two methods were comparable, with the exception of few cases, where the retinoblastoma protein appeared detectable but unable to bind to the viral oncoprotein. The retinoblastoma protein has been found defective mostly in the M3 promyelocytic subtype.

The diabetic milieu modulates the advanced glycation end product-receptor complex in the mesangium by inducing or upregulating galectin-3 expression.

Nonenzymatic glycation has been implicated in the pathogenesis of the dysregulated tissue remodeling that characterizes diabetic glomerulopathy, via the formation of advanced glycation end products (AGEs) and their binding to cell surface receptors. Several AGE-binding proteins have been identified so far, including p60, p90, and the adhesive and growth-regulating lectin galectin-3 (Gal-3), the components of the so-called AGE-receptor complex. This study aimed to evaluate the mesangial expression of the AGE-receptor complex and its modulation by the diabetic milieu, both in vivo, in non-diabetic versus streptozotocin-induced diabetic rats, and in vitro, in mesangial cells exposed to either normal glucose (NG) levels (5.5 mmol/l), as compared with high glucose (HG) levels (30 mmol/l) and iso-osmolar mannitol (M), or to native bovine serum albumin (BSA), as compared with glycated BSA with AGE formation (BSA-AGE) and glycated BSA in which AGE formation was prevented by aminoguanidine (BSA-AM). In vivo, Gal-3 protein and mRNA were not detectable in glomeruli from nondiabetic rats until 12 months after initiating the study. On the contrary, in diabetic rats, Gal-3 expression was observed at 2 months of disease duration, and it increased thereafter. Both p60 and p90 immunoreactivities were observed at the glomerular level with slightly increased expression of p90, but not p60, in diabetic versus nondiabetic animals. In vitro, Gal-3 was not detectable in mesangial cells cultured in NG (although it became evident after a certain number of passages in culture), whereas Gal-3 was detectable in cells grown on BSA. Prolonged exposure (2-4 weeks) of mesangial cells to HG but not to M, as well as growing cells on BSA-AGE and, to a lesser extent, BSA-AM, induced or significantly increased the expression of Gal-3, both protein (up to 2.65-fold) and mRNA (up to 3.10-fold) and its secretion in the medium (by approximately 50%). Both p60 and p90 were demonstrated in mesangial cells under NG conditions, and the expression of p90, but not p60, was upregulated by approximately 20% by HG or BSA-AGE. These results indicate that 1) under basal conditions, Gal-3, unlike p90 and p60, is not detectable in the mesangium but becomes expressed with aging and 2) the diabetic milieu induces or upregulates Gal-3 production, whereas it increases only slightly the expression of p90, but not p60. Gal-3 expression or overexpression may modulate the AGE-receptor-mediated events by modifying the function of the AGE-receptor complex. Additionally, it may exert direct effects on tissue remodeling by virtue of its adhesive and growth-regulating properties.

Accelerated diabetic glomerulopathy in galectin-3/AGE receptor 3 knockout mice.

Several molecules were shown to bind advanced glycation end products (AGEs) in vitro, but it is not known whether they all serve as AGE receptors and which functional role they play in vivo. We investigated the role of galectin-3, a multifunctional lectin with (anti)adhesive and growth-regulating properties, as an AGE receptor and its contribution to the development of diabetic glomerular disease, using a knockout mouse model. Galectin-3 knockout mice obtained by gene ablation and the corresponding wild-type mice were rendered diabetic with streptozotocin and killed 4 months later, together with age-matched nondiabetic controls. Despite a comparable degree of metabolic derangement, galectin-3-deficient mice developed accelerated glomerulopathy vs. the wild-type animals, as evidenced by the more pronounced increase in proteinuria, extracellular matrix gene expression, and mesangial expansion. This was associated with a more marked renal/glomerular AGE accumulation, indicating it was attributable to the lack of galectin-3 AGE receptor function. The galectin-3-deficient genotype was associated with reduced expression of receptors implicated in AGE removal (macrophage scavenger receptor A and AGE-R1) and increased expression of those mediating cell activation (RAGE and AGE-R2). These results show that the galectin-3-regulated AGE receptor pathway is operating in vivo and protects toward AGE-induced tissue injury in contrast to that through RAGE.

Apolipoprotein E polymorphism as a risk factor for vascular disease in diabetic patients.

OBJECTIVE: To examine the prevalence of cardiovascular disease in diabetic patients as a function of apolipoprotein (apo) E polymorphism. RESEARCH DESIGN AND METHODS: The apo E phenotypes and plasma lipid, lipoprotein, and apo levels were determined for 517 Italian diabetic patients. The prevalence of cardiovascular disease (defined as ischemic heart disease [HD] and/or peripheral vascular disease and/or cerebrovascular disease) was assessed as a function of apo E polymorphism at entry and after 4 years. RESULTS: The occurrence of vascular disease did not differ significantly between diabetic patients in the various categories of apo E phenotype either at entry into the study or after 4 years. When expressed as a percentage of patients with disease, we observed--for E2, E3, and E4 carriers, respectively--at entry: IHD, 20.0% (n = 14), 21.0% (n = 79), and 21.5% (n = 14); and macroangiopathy, 24.3% (n = 17), 29.3% (n = 110), and 24.6% (n = 16). Apo E polymorphism did not make a significant contribution to multiple logistic regression models designed to identify the factors associated with the occurrence of vascular disease in diabetic patients. CONCLUSION: Apo E polymorphism and, notably, the apo E4 allele cannot be universally considered as a particular risk factor for cardiovascular disease in diabetic patients.

Role of galectin-3 as a receptor for advanced glycosylation end products.

The advanced glycosylation end product (AGE)-binding proteins identified so far include the components of the AGE-receptor complex p60, p90 and galectin-3, receptor for advanced glycosylation end products (RAGE), and the macrophage scavenger receptor types I and II. Galectin-3 interacts with beta-galactoside residues of several cell surface and matrix glycoproteins through the carbohydrate recognition domain and is also capable of peptide-peptide associations mediated by its N-terminus domain. These structural properties enable galectin-3 to exert multiple functions, including the modulation of cell adhesion, the control of cell cycle, and the mRNA splicing activity. Moreover, in macrophages, astrocytes, and endothelial cells, galectin-3 has been shown to exhibit a high-affinity binding for AGEs; the lack of a transmembrane anchor sequence or signal peptide suggests that it associates with other AGE-receptor components rather than playing an independent role as AGE-receptor. In tissues that are targets of diabetic vascular complications, such as the mesangium and the endothelium, galectin-3 is not expressed or only weakly expressed under basal conditions, at variance with p90 and p60 but becomes detectable with aging and is induced or up-regulated by the diabetic milieu, which only slightly affects the expression of p90 or p60. This (over)expression of galectin-3 may in turn modulate AGE-receptor-mediated events by modifying the function of the AGE-receptor complex, which could play a role in the pathogenesis of target tissue injury. Up-regulated galectin-3 expression may also exert direct effects on tissue remodeling, independently of AGE ligands, by virtue of its adhesive and growth regulating properties.

Blood pressure self-measurement in the elderly: differences between automatic and semi-automatic systems.

Arterial hypertension is the most common cardiovascular risk factor in the elderly. Its clinical control emphasises the problem of the systems used for monitoring: clinical measurement by the physician, home self-monitoring, ambulatory monitoring, etc. In particular, in the elderly population, the self-monitoring of blood pressure can present further problems associated with their situation. In our study we evaluated, in an elderly population, the differences in the self-recording of blood pressure with automatic and semi-automatic equipment using a mercury sphygmomanometer by a physician as a 'gold standard' control. We studied 28 elderly subjects using a rigid protocol for the self-measurement of their blood pressure. Our results show that automatic equipment is significantly more precise and easier to use than semiautomatic equipment in home self-measurement of blood pressure in elderly people.

Effect of lonidamine on the mitochondrial potential in situ in Ehrlich ascites tumor cells.

The effect of lonidamine (LND) on the mitochondrial membrane potential, in situ, of Ehrlich ascites tumour cells was investigated by using the safranine method. LND, because of its ability to inhibit electron transport from endogenous substrates to respiratory carriers, induced a de-energization of mitochondria. Addition of glucose to rotenone-treated cells induced mitochondrial membrane potential as shown by the spectral shift similar to that which occurred upon energization of mitochondria. The build-up of membrane potential in rotenone-treated cells was due to glycolytically-generated ATP because the response to glucose was abolished by LND which inhibited the glycolysis of neoplastic cells by affecting the mitochondria bound hexokinase.

The mild hypertension enigma.

This study examines the problem of the correlation between mild arterial hypertension and cardiovascular damage. The authors examine the results of the most important trials carried out and, on the basis of their evaluations, suggest the need to review the current clinical policy of considering mild arterial hypertension as an important risk factor directly related to cardiovascular disease. Since the therapeutic trials carried out on mild hypertension did not substantially reduce the total and cardiac mortality rate, it seems to be probable that arterial hypertension is a progression acceleration marker of atheromatous disease. According to this theory, a therapy which aims merely at returning the pressure values to normal limits will probably not change the natural course of the atheromatous process.

Permanent cardiac pacing and thromboembolic risk in elderly patients.

In patients undergoing permanent cardiac pacing, the maintenance of atrial contractility is important to ensure adequate ventricular filling and to guarantee an optimal ventricular ejection capacity. The appropriate pacing mode, assuring a suitable mechanical atrioventricular coupling, prevents the onset of atrial fibrillation and contributes to reduction of the risk of subsequent systemic and pulmonary thromboembolic episodes. We examined 461 patients (266 males and 195 females, aged between 52 and 97 years, average age 76.5 +/- 18) paced for conduction disturbances of various degrees and etiology. Of them, 323 patients received ventricular demand pacemaker (VVI group, average age 77.9 years); 138 underwent dual chamber pacing (DCP group, average age 75.2 years), 117 of the latter received universal demand pacing (DDD) and 21 atrial synchronous ventricular demand pacing (VDD). The patients were subsequently divided into two age-groups: Group A (/= 75 years, 287 patients). According to pacing mode and successive development of stable atrial fibrillation (AF), we analysed the occurrence of systemic and/or pulmonary thromboembolic episodes and the incidence of fatal events. During our study, performed from January 1986 to August 1993, 70 embolic episodes were observed in the VVI group and six in the DCP group. Eighty-four patients with VVI units developed AF during follow-up, compared with only five patients in the DCP group. Our data indicate that VVI patients have a higher incidence of AF, embolic complications and cerebrovascular mortality, in comparison with the DCP group. VVI pacing should be avoided, especially in older patients, when atrial rhythmical activity is present.

On the interrelationship between serum parathormone levels and osteoporosis in old humans.

Seventy-eight persons (51 females, 29 males) of an average age of slightly higher than 65 yr were studied, suffering mostly from cardiovascular diseases or various degrees of osteo-arthropathies. The so-called compacta index was calculated from the values of the external and internal diameters measured radiologically in the central region of the left-hand second metacarpus. Serum parathormone levels were assayed by radioimmunological methods. Furthermore, a series of other parameters regarding the composition of the serum have been recorded. Statistical analysis of the data obtained revealed no correlation between the serum parathormone level and the compacta index actually found in the patients. Therefore, one can conclude that the senile bone-loss has no common aetiopathogenetic basis with the uraemic osteodystrophies or all other forms of increased parathormone production. The serum levels of parathormone did not increase with aging; on the contrary, as it is known for other hormones, they display a decreasing tendency. However, this decrease proved to be statistically insignificant. Otherwise, the age- and sex-related alterations of the bone mass observed in the patients studies agree with the general knowledge.

The effects of a rehabilitation program with mnemotechniques on the institutionalized elderly subject.

After having screened the cognitive functions in 103 institutionalized elderly subjects in Terni, a sample affected by mnemic deficit was obtained so as to verify the use of mnemotechniques on the same. Generally the findings show an improvement in cognitive performance in those treated which leads to suppose that our patients were affected by apparent cognitive deficits rather than real ones, supporting in any case the use of neuropsychological rehabilitative treatment in institutionalized subjects.

The Camerano study on hypertension: the problem of arterial hypertension in the elderly.

The Camerano study on arterial hypertension (AH) was a cross-sectional study, carried out on a large population sample in a small town in central Italy. The main goal was to reveal both the prevalence and certain characteristics of AH in the population examined. The main results, can be summarized as follows: (i) The occurrence of AH in the old (65-74 years) and very old (> or = 75 years) groups was 43.3 and 57.4%, respectively. (ii) isolated systolic hypertension (ISH) was found in 1.7, 23.6 and 3.9% in the adult, old and very old subjects, respectively. (iii) The association of AH with some of the more common cardiovascular risk factors (dyslipidemia, hyperglycemia, obesity, etc.) was significant for all the risk factors in the adult group, while in the old group there was a significant association only with the body mass index. (iv) Blood pressure (BP) values during the medical visits were evaluated, and adult versus old subjects were compared, but no significant differences were found.

An EEG power index (eyes open vs. eyes closed) to differentiate Alzheimer's from vascular dementia and healthy ageing.

EEG differential power patterns between Alzheimer's (AD, 50 patients) and vascular (VaD, 37 patients) dementia and between these two and 36 healthy ageing subjects, were studied in the 6.5-12 Hz band of the ongoing EEG recorded during the rest eyes closed (REC) and eyes open (REO) conditions. From the EEGs (16 electrodes, 10-20 international system except for Fz, Cz, Pz), a 6.5-12 Hz band, wider than the alpha range (alpha-like), was chosen and processed to include the highest theta frequencies characterising the occipital dominant activity in dementia. A global and occipital EEG Power Index (PI) was calculated and used considering the absolute powers during REC and REO. The MANOVA was used to compare the figures. Bearing in mind that the higher the PI value the greater the difference between the 6.5-12 Hz EEG band powers of REC vs. REO, the results were as follows: (i) in the patients with Alzheimer's and vascular dementia the global and occipital PIs were significantly lower than those in controls; (ii) in the patients with Alzheimer's dementia the same PIs were significantly lower that those of the patients with VaD; (iii) healthy elderly subjects showed significantly lower powers in the 6.5-12 Hz frequencies at T5 and O1 in REO as compared to dementia patients. The pathophysiological implications and the clinical applications of these results are discussed.

The influence of age and sex on nutritional parameters in subjects aged 60 years and over.

The nutritional assessment of the elderly shows several interpretative difficulties due to the lack of standard parameters. Moreover chronic age-related diseases can interfere with the physiological nutritional status. Anthropometric (triceps skinfold, arm muscle area, total body muscle mass, fat mass and Body Mass Index (BMI)), biochemical (serum prealbumin, transferrin, ceruloplasmin, total protein and albumin) and immunological (serum lymphocytes) parameters were measured in 583 out-patients aged 60 years or over selected on the basis of clinical and biochemical criteria and with BMI /= 75) for each sex. The F-test analysis for all anthropometric parameters except BMI showed significant differences with respect to age (P < 0.05) and sex (P < 0.05). Among biochemical parameters, prealbumin showed a significant difference for age (P < 0.05) and sex (P < 0.05) (males, 30.3 +/- 8.2; females, 29.1 +/- 7.5) while ceruloplasmin showed a significant difference for sex only (P < 0.05) (males, 40.9 +/- 9.3; females, 43.8 +/- 8.2). When the biochemical mean values obtained in this study were compared with those utilized in the daily routine of the hospital central laboratory, ceruloplasmin and prealbumin resulted in significantly higher (P < 0.05) while total protein and albumin were significantly lower values (P < 0.05).

[The problem of hypercholesterolemia in the aged]. / Il problema dell'ipercolesterolemia nell'anziano.

This paper deals with the problems of hypercholesterolaemia in the elderly. We have significant results that show an important relationship between serum cholesterol and cardiovascular diseases in the adult, but the same has not yet been definitely established for the elderly. After examination of the available data, the Authors suggest that--after a through clinical evaluation--the elderly should also be treated given that there are data to suggest and hypothesize the positive action of a hypolipemic diet until at least the age of seventy five years. The therapy, whenever possible, could be dietetic; but from relevant results obtained, used together with HMG-CoA reductase inhibitors, these drugs are a good therapeutic approach to the problem, also in the elderly. To support this opinion, the Authors show the results obtained with the use of Simvastatin in a group of old patients.

Neuroendocrine-thymus interactions. I. In vitro modulation of thymic factor secretion by thyroid hormones.

Several in vivo experimental and clinical studies suggest that the production of thymic hormones, such as thymulin (Zn-FTS), is modulated by thyroid hormones. It was not determined in these studies, however whether such modulation is exerted directly on the thymic epithelial cells which synthesize and secrete thymic hormones. In order to discriminate between direct and indirect modulation, the effect of thyroid hormones on the in vitro production of thymulin by whole thymic organ culture, as detected by the rosette inhibition assay, has been investigated. Donors of thymuses were young 6N-propyl-2 thiouracil (PTU)-treated hypothyroid Balb/c mice and normal littermates. Thymuses from hypothyroid mice were shown to produce concentrations in vitro nearly undetectable of thymic hormone, when compared to thymuses from normal mice. The in vitro addition of triiodothyronine (T3) caused a complete recovery of the thymic hormone production by thymuses from hypothyroid mice and an increased synthesis even by normal thymuses over control values. The complete blockade of in vitro thymic hormone production with cycloheximide, which inhibits mRNA and protein synthesis but not thyroid hormone permissive actions, suggests that the T3 induced increment of thymic hormone level in the supernatant is due to de novo synthesis. Furthermore, the number of thymulin-producing cells, as detected by immunofluorescence using a specific antithymulin monoclonal antibody, which is quite low in thymuses from hypothyroid mice, is completely regained after in vitro incubation with T3. These findings support the idea that the modulation of thyroid hormones on thymic endocrine activity is directly exerted at thymic level.

[The coronal anatomy of the pelvis at rest and under straining]. / Anatomia coronale della pelvi a riposo e sotto sforzo.

Twenty-five subjects with no pelvic floor dysfunctions at defecography were examined with direct coronal CT scans of the pelvis at rest and on straining. Three compartments with different characteristics were delimited by two planes-the anterior one being tangent to the ischiatic foramen and the posterior one to the ischial tuberosities. At rest, the average length of the levator ani muscle and the surface of the supralevator space were significantly lower posteriorly than in the other two compartments (48.3 mm +/- 7.9; 48.8 mm +/- 7; 42.6 mm +/- 9.4, p < 0.05 and 70.6 cm2 +/- 7.5; 66.9 cm2 +/- 11.2; 27.2 cm2 +/- 4.8, p < 0.01, respectively). On straining, maximum muscle lengthening occurred posteriorly, as indicated by similar average values (63.7 mm +/- 12.7; 63.3 mm +/- 9.5 and 60.5 mm +/- 14) and the corresponding increase (+12.5%) in the supralevator space occurred in the middle compartment (73.8 cm2 +/- 7.6; 75.3 cm2 +/- 11.6 and 30.2 cm2 +/- 5.2). To conclude, our method proved reliable enough (intra- and interobserver correlation index > 80%) and promising for future clinical applications and studies of pelvic floor dysfunctions.