Plasma atrial natriuretic peptide levels in children with cardiac diseases: correlation with cGMP levels and haemodynamic parameters

In children with various forms of cardiac diseases (aged 2 months to 16 years) significantly higher plasma atrial natriuretic peptide (ANP; range 36-680, median 247 pg/ml) and cyclic 3'5'-guanosine monophosphate (cGMP; range 0.2-46, median 8.2 pmol/ml) levels were found than in control children (p less than 0.0001). In control children (aged 4 months to 17 years) plasma ANP and cGMP levels were measured in the range of 2.4-98 pg/ml and of 0.2-2.8 pmol/ml, respectively. There was a linear correlation between the two parameters in children with cardiac diseases (r = 0.62, p less than 0.01). Children with elevated mean right atrial pressure (i.e., greater than 6 mm Hg) showed significantly higher plasma ANP levels than children with normal atrial pressure (p less than 0.01). However, there was only a weak linear correlation between mean right atrial pressure and plasma ANP levels (r = 0.48, p less than 0.01). Plasma ANP levels from right atrium, pulmonary artery, left atrium and left ventricle were significantly higher than those from vena cava (p less than 0.05). Analysis of ANP-like immunoreactive material by high performance liquid chromatography suggested that alpha-ANP is the major form of circulating ANP in blood of children with cardiac diseases.     

Fluctuations in peripheral serum testosterone levels within a day, with age and by sexual stimulation in male beagle dogs bred indoors

Fluctuations in serum levels of testosterone (T) within a day, both with age and as a result of sexual stimulation, were examined in male beagle dogs. Eighty male dogs aged between 3 months and 16 years and bred in our laboratory were used under strictly controlled breeding conditions (temperature: 22 +/- 1 degree C, relative humidity: 55 +/- 5%, lighting time: 8:00 a.m.-8:00 p.m.). The level of T was measured by an RIA method. In order to examine the fluctuation in T level within a day, blood samples were obtained at 0:00, 6:00, 12:00 and 18:00 in each of five dogs aged 1.7 and 2.1 years. T levels fluctuated with a regular pattern that was lowest at 12:00, and increased to a peak at 18:00-6:00, thereafter decreasing until 12:00. In order to examine the change in T level with age, blood samples were obtained at 9:00, 12:00 and 16:00 from 70 dogs aged between 3 months and 16 years. The regular diurnal pattern of T level was usually seen, and the levels at 12:00 were always low and did not fluctuate at any age except for 6 months, and 13, 14 and 16 years. The T level at 9:00 increased to reach a peak at 4 years, whereas that at 16:00 did so at 2 years. T levels at 9:00 were significantly higher at 4-12 and 14 years than at 3 months, and were higher at 4 years than at 9 months.(ABSTRACT TRUNCATED AT 250 WORDS)     

外源基因转染导致小鼠体细胞过快衰老 及p16INK4a表达水平变化

对小鼠胎儿成纤维细胞进行外源基因转染时发现, 外源基因转染后的小鼠体细胞染色体端粒的长度以每代47 bp碱基缩短; 在转染后的衰老细胞中, 或细胞随着增龄, p16^INK4a 5′-调控区DNA甲基化程度逐渐降低; 利用RT-PCR与Northern blot证明, 衰老细胞与年轻细胞中的p16^INK4a基因的表达水平存在显著差异, 传代45代的细胞和外源基因转染后的衰老细胞p16^INK4a基因的表达水平大约是原代细胞的12~16倍, 而原代细胞与20代细胞间的差异很小。外源基因转染后的衰老细胞核移植后能支持克隆胚胎的体外早期发育。     

Detection of Mycoplasma fermentans in saliva sampled from infants, preschool and school children, adolescents and adults by a polymerase chain reaction-based assay.

Attempts were made to detect Mycoplasma fermentans in saliva sampled from 201 subjects (108 males and 93 females) aged from 4 months to 59 years by a polymerase chain reaction-based assay. M. fermentans was detected in saliva from 110 (54.7%) of 201 subjects, and 10 (28.6%) of 35 subjects aged from 4 months to 3 years. Of ten positive subjects, three were aged from 16 to 23 months and five were from 26 to 31 months. The incidence tended to increase with age up to the teens. The incidence was significantly greater in teenagers than in subjects aged from 7 to 12 years, but there was no significant difference in the incidence between the group of teenagers and each of the groups of subjects older than the teenagers. Thus, it was suggested that M. fermentans colonized the mouth at the age of about 16 months up to the age of 19 years.     

Restored immune cell functions upon clearance of senescence in the irradiated splenic environment

Some studies show eliminating senescent cells rejuvenate aged mice and attenuate deleterious effects of chemotherapy. Nevertheless, it remains unclear whether senescence affects immune cell function. We provide evidence that exposure of mice to ionizing radiation (IR) promotes the senescent‐associated secretory phenotype (SASP) and expression of p16^INK4a in splenic cell populations. We observe splenic T cells exhibit a reduced proliferative response when cultured with allogenic cells in vitro and following viral infection in vivo. Using p16‐3MR mice that allow elimination of p16^INK4a‐positive cells with exposure to ganciclovir, we show that impaired T‐cell proliferation is partially reversed, mechanistically dependent on p16^INK4a expression and the SASP. Moreover, we found macrophages isolated from irradiated spleens to have a reduced phagocytosis activity in vitro, a defect also restored by the elimination of p16^INK4a expression. Our results provide molecular insight on how senescence‐inducing IR promotes loss of immune cell fitness, which suggest senolytic drugs may improve immune cell function in aged and patients undergoing cancer treatment.     

Development of binuclearity and DNA-polyploidization in the growing mouse liver

Summary Suspensions of intact liver cells were prepared from 36 male NMRI mice of different age after perfusion of the liver with ice-cold calcium- and magnesium-free phosphate buffer (CMF). The suspensions of the isolated hepatocytes were smeared on slides, fixed, hydrolized and stained by fluorescent acriflavine-Schiff-Feulgen reaction. The number of nuclei per cell was determined in a phase-contrast microscope. Quantitative fluorescent cytophotometric measurements of nuclear Feulgen-DNA were performed on individual nuclei. At the age of 0.5 month, 55% of the hepatocytes were found to be mononuclear, 45% binuclear. In the animal groups aged 1 month, 1.5 months, 3 months, 6 months and 12 months, the percentage of binuclear hepatocytes remained constant at about 80%. Very few liver cells with 3 or 4 nuclei were detected. Feulgen-DNA-measurements revealed a predominance of 2c and 4c nuclei at ages 1 month and 1.5 months with logarithmic increase of 8c nuclei and a decrease of the 2c nuclei. From 1.5 months on 16c nuclei were found, which never exceeded 8%. When total DNA-ploidy of the hepatocytes was calculated similar kinetics at a higher ploidy level were observed. 2c hepatocytes existed in small percentages at very young ages up to 1.5 months, but were also occasionally found in older animals. With increasing age the number of 16c hepatocytes increased logarithmically with a concomitant decrease of the 4c hepatocytes. The percentage of 8c liver cells remained more or less constant. Few hepatocytes with a 32c total DNA content were found in mice aged 3 months and older. In one-year-old mice the mean DNA-ploidy was calculated to be 5.8c per liver nucleus and 10.0c per whole hepatocyte.Supported by Deutsche Forschungsgemeinschaft, Grant No Bo 395/5     

Effects of ageing on morphology,amylase release,cytosolic Ca2+ signals and acyl lipids in isolated rat parotid gland tissue

Xerostomia (oral dryness sensation) is due to dryness of the oral cavity and it is more prevalent in the elderly. This study investigated the effect of ageing on parotid gland structure and function of control (2-6 months) and aged (12, 16-18 and 22-24 months) rats employing light microscopic, colorimetric, gas chromatographic and microspectrofluorimetric methods to investigate the morphological changes of the parotid glands, amylase release, endogenous lipid distribution and cytosolic free calcium levels, respectively. When compared to controls, age-related changes were apparent in glands obtained from rats aged 16-18 and 22-24 months, which included reduced acinar cell distribution, enlarged parotid ducts with fatty and connective tissue and mast cell infiltrations. Parotid acini from 12, 16-18 and 22-24-month-old glands showed significant (p < 0.05) age-related decreases in amylase release, compared to controls when challenged with acetylcholine (ACh). No change in basal calcium signals was observed in parotid acini from 2-6 to 16-18-month-old-animals. However, stimulation of 16-18-month-old parotid acini with 10(-5)M ACh resulted in a significant (p < 0.001) decrease in both peak and plateau phases of the cytosolic Ca2+ signal when compared to control. Gas chromatography of de novo and essential acyl lipids revealed no changes in the amount of either acyl lipid group in glands obtained from 2-6 to 22-24-month-old animals. Lipid analysis of phospholipid associated acyl chains showed a higher relative proportion of linoleic acid in older glands. The results reveal that ageing is associated with marked and distinct morphological changes including infiltrations of lipids and mast cells of the parotid gland and decreases in amylase release and cytosolic Ca2+ signals.     

Age- and gender-dependent obesity in individuals with 16p11.2 deletion

Recurrent genomic imbalances at 16p11.2 are genetic risk factors of variable penetrance for developmental delay and autism.Recently,16p11.2 (chr16:29.5 Mb-30.1 Mb) deletion has also been detected in individuals with early-onset severe obesity.The penetrance of 16p11.2deletion as a genetic risk factor for obesity is unknown.We evaluated the growth and body mass characteristics of 28 individuals with 16p11.2(chr16:29.5 Mb-30.1 Mb) deletion originally ascertained for their developmental disorders by reviewing their medical records.We found that nine individuals could be classilied as obese and six as overweight.These individuals generally had early feeding and growth difficulties,and started to gain excessive weight around 5-6 years of age.Thirteen out of the 18 deletion carriers aged 5 years and older (72％) were overweight or obese,whereas only two of 10 deletion carriers (20％) younger than five were overweight or obese.Males exhibited more severe obesity than females.Thus,the obesity phenotype of 16p11.2 deletion carriers is of juvenile onset,exhibited an age.and gender-dependent penetrance.16p11.2 deletion appears to predispose individuals to juvenile onset obesity and in this case are similar to the well-described Prader-Willi syndrome (PWS).Early detection of this deletion will provide opportunity to prevent obesity.     

p16(INK4A) immunohistochemical overexpression in premalignant and malignant oral lesions infected with human papillomavirus.

Human papillomavirus (HPV) is believed to promote the oncogenic process, and the correlation between viral oncoproteins and dysfunction of p16(INK4A) tumor suppressor protein in oral lesions is controversial. To test the hypothesis that anogenital HPV types participate in disruption of the regulation of p16(INK4A) suppressor protein in oral lesions, we analyzed 46 oral biopsy specimens for the presence of HPV 6/11 and 16/18 by in situ hybridization (ISH) and for p16(INK4A) expression by immunohistochemistry (IHC). Eighteen (39%) of the 46 oral lesions were HPV-positive and 28 (61%) were HPV-negative. HPV 6/11 DNA was found in 5 (11%) and HPV 16/18 in 13 (28%) of 46 biopsies. Nine of the 18 HPV-positive oral lesions (50%), assessed by catalyzed signal amplification coupled to ISH (CSA-ISH), gave high-intensity p16(INK4A) immunostaining. Focal and diffuse patterns were observed in 11/13 (77%) lesions with HPV 16/18, focal immunopositivity in 3/5 (80%) with HPV 6/11, and negative or sporadic p16-labeling in 18/28 (64%) without the presence of HPV DNA. These results showed a strong association between overexpression of p16 protein and malignant oral lesions, mainly those infected by HPV 16/18. We can conclude that high-risk HPV types are associated with p16 overexpression, and p16 may serve as a biomarker in oral cancer related to high-risk HPV infection.     

Long‐term repopulation of aged bone marrow stem cells using young Sca‐1 cells promotes aged heart rejuvenation

Reduced quantity and quality of stem cells in aged individuals hinders cardiac repair and regeneration after injury. We used young bone marrow (BM) stem cell antigen 1 (Sca‐1) cells to reconstitute aged BM and rejuvenate the aged heart, and examined the underlying molecular mechanisms. BM Sca‐1⁺ or Sca‐1^? cells from young (2–3 months) or aged (18–19 months) GFP transgenic mice were transplanted into lethally irradiated aged mice to generate 4 groups of chimeras: young Sca‐1⁺, young Sca‐1^?, old Sca‐1⁺, and old Sca‐1^?. Four months later, expression of rejuvenation‐related genes (Bmi1, Cbx8, PNUTS, Sirt1, Sirt2, Sirt6) and proteins (CDK2, CDK4) was increased along with telomerase activity and telomerase‐related protein (DNA‐PKcs, TRF‐2) expression, whereas expression of senescence‐related genes (p16^INK4a, P19^ARF, p27^Kip1) and proteins (p16^INK4a, p27^Kip1) was decreased in Sca‐1⁺ chimeric hearts, especially in the young group. Host cardiac endothelial cells (GFP^?CD31⁺) but not cardiomyocytes were the primary cell type rejuvenated by young Sca‐1⁺ cells as shown by improved proliferation, migration, and tubular formation abilities. C‐X‐C chemokine CXCL12 was the factor most highly expressed in homed donor BM (GFP⁺) cells isolated from young Sca‐1⁺ chimeric hearts. Protein expression of Cxcr4, phospho‐Akt, and phospho‐FoxO3a in endothelial cells derived from the aged chimeric heart was increased, especially in the young Sca‐1⁺ group. Reconstitution of aged BM with young Sca‐1⁺ cells resulted in effective homing of functional stem cells in the aged heart. These young, regenerative stem cells promoted aged heart rejuvenation through activation of the Cxcl12/Cxcr4 pathway of cardiac endothelial cells.     

Repair of senescent myocardium by mesenchymal stem cells is dependent on the age of donor mice

Myocardial infarction is one of the leading causes of mortality in aged people. Whether age of donors of mesenchymal stem cells (MSCs) affects its ability to repair the senescent heart tissue is unknown. In the present study, MSCs from young (2 months) and aged (18 months) green fluorescent protein expressing C57BL/6 mice were characterized with p16^INK4a and β‐gal associated senescence. Myocardial infarction was produced in 18‐month‐old wild‐type C57BL/6 mice transplanted with MSCs from young and aged animals in the border of the infarct region. Expression of p16^INK4a in MSCs from aged animals was significantly higher (21.5%± 1.2, P < 0.05) as compared to those from young animals (9.2%± 2.8). A decline in the tube‐forming ability on Matrigel was also observed in aged MSCs as well as down‐regulation of insulin‐like growth factor‐1, fibroblast growth factor (FGF‐2), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) compared to young cells. Mice transplanted with young MSCs exhibited significant improvement in their left ventricle (LV) systolic and diastolic function as demonstrated by dp/dt_max, dp/dt_min, P_max. Reduction in the LV fibrotic area was concomitant with neovascularization as demonstrated by CD31 and smooth muscle actin (SMA) expression. Real‐time RT‐PCR analysis for VEGF, stromal cell derived factor (SDF‐1α) and GATA binding factor 4 (GATA‐4) genes further confirmed the effect of age on MSC differentiation towards cardiac lineages and enhanced angiogenesis. These studies lead to the conclusion that repair potential of MSCs is dependent on the age of donors and the repair of senescent infarcted myocardium requires young healthy MSCs.     

Serum thyroid hormone concentrations during growth and puberty in Carora dairy heifers of Venezuela

The aim of this study was to characterize changes in serum concentrations of triiodothyronine (T(3)) and thyroxine (T(4)) in relation to growth and the onset of puberty in Carora heifers, a Venezuelan dairy breed. Heifers aged 7 to 16 months were grouped retrospectively according to puberty status into 4 groups: Pubertal (control group; n = 12) and nonpubertal (n = 8) contemporary (born during the same week) heifers, pubertal (n = 7.) and nonpubertal (n = 7) noncontemporary (born in different months) heifers. A split-plot model with repeated measures over Months 7 to 16 of age was used. Control heifers attained puberty at 290 +/- 5 kg body weight (BW) between 13 and 14 months of age. Significant (P < 0.01) interactions of birth time of year and puberty status were detected in BW and serum concentrations of T(3), but only interaction of birth time of year was found in T(4). A transient but significant (P < 0.05) decrease in T(3) secretion was seen in pubertal contemporary and noncontemporary (101 +/- 4 and 113 +/- 4 ng/d1, respectively) heifers at Month 12 of age, a change which could be critical to the onset of puberty. Significant (P < 0.05) positive correlation was found between BW and T(3). In summary, thyroid hormone secretion changed across the months of growing and around the onset of puberty in Carora heifers.     

131I]metaiodobenzylguanidine therapy in 20 patients with malignant pheochromocytoma.

Twenty patients, 16 male and 4 female (aged 11-76 years), with metastatic pheochromocytoma were treated in our Institution between 1985 and 1990. Metastases occurred in all patients: at presentation in 11 patients, with a 10 to 30 month delay in 7 patients, and 9 and 28 years later respectively in 2 patients. Catecholamines hyperproduction was present in all patients. Metaiodobenzylguanidine (MIBG) uptake was found in 16 patients after a diagnostic dose and only after a therapeutic dose in 1 patient. Surgery was performed on primary tumor (18 patients) and on distant metastases (10 patients). 131I-MIBG therapy was performed in 11 patients, 9 of whom were evaluable. The cumulative activity ranged from 3.7 to 26.3 GBq (100 to 711 mCi) in 1 to 6 courses. We observed symptomatic improvement (5 patients) and partial tumor response in 2 patients, which lasted for 28 and 9 months respectively, terminating with a rapidly progressing disease involving the bone marrow. Stabilisation was observed in 3 patients. Moderate myelosuppression occurred in 4 patients. Fifteen patients died with a median survival of 16 months (range 3-60). Response to therapy was poor and further evaluation of the presently available therapeutic approaches is needed.     

The 5′-flanking region of the E1 α form of the murine p16 (MTS1) gene

We have PCR-amplified and sequenced the immediate (841 bp) 5′-flanking region of murine p16^INK4a (MTS1, CDKN2) tumor suppressor gene. Comparing to recently published 5'-flanking region of the human α form of p16^INK4a, homologies were found in several regions of murine p16^INK4a-α putative promoter sequence.     

5-Fluorouracil or gemcitabine combined with adenoviral-mediated reintroduction of p16INK4A greatly enhanced cytotoxicity in Panc-1 pancreatic adenocarcinoma cells

BACKGROUND: Pancreatic cancer is one of the most lethal of all the common gastrointestinal malignancies. Although surgery offers the best chance for survival, it is not appropriate for all cases. The only adjuvant treatment to show promise is chemotherapy. Hence new treatments are urgently sought. We previously reported that adenoviral (Ad)-mediated delivery of p53 (Adp53) and p16(INK4A) (Adp16) significantly inhibited the growth of pancreatic cancer cell lines and established subcutaneous pancreatic tumours in nude mice (Ghaneh P, et al. Adenovirus mediated transfer of p53 and p16INK4A results in pancreatic cancer regression in vitro and in vivo. Gene Ther 2001; 8: 199-208). In this study we examine whether combining Ad-mediated delivery of p53 or p16(INK4A) with clinically relevant chemotherapeutic drugs has therapeutic potential for pancreatic cancer. METHODS AND RESULTS: Four pancreatic adenocarcinoma cell lines were evaluated for their sensitivity to 5-fluorouracil (5-FU) and gemcitabine and two of these, Suit-2 and Panc-1, were chosen for combination experiments because they showed moderate and poor sensitivity, respectively, to 5-FU and gemcitabine. We found no evidence for enhanced cytotoxicity when either cell line was transduced with Adp53 before or after incubation with chemotherapeutic drugs. In contrast, incubation of Panc-1 cells with either 5-FU or gemcitabine followed by Ad-mediated overexpression of p16(INK4A) resulted in a substantial reduction in cell viability under conditions where the drugs alone had minimal cytotoxicity. Incubation of Suit-2 cells with 5-FU followed by Ad-mediated overexpression of p16(INK4A) also resulted in a significant reduction in cell viability. This, however, was observed only with higher concentrations of 5-FU and viral vector. Cell cycle analysis of Panc-1 cells showed that the combination of cytotoxic drugs and Adp16 resulted in an increase in the sub-G1 population suggesting an increase in apoptosis. Dual labelling of these cells with annexin V and propidium iodide (PI) confirmed that the combination of 5-FU and Adp16 resulted in a significant increase in early apoptotic cells (annexin V positive and PI negative) compared with controls. Moreover, overexpression of p16(INK4A) was associated with a reduction in pRb levels in these cells-high levels of pRb have been proposed to contribute to chemoresistance in pancreatic cancer cells. CONCLUSIONS: We have shown that the currently used chemotherapeutic drugs for pancreatic adenocarcinoma combined with restoration of p16(INK4A) expression hold promise for the adjuvant treatment of this disease. Importantly, the combination facilitated the use of chemotherapeutic drugs at lower concentrations than would otherwise be effective.     

TP53 and p16INK4A, but not H-KI-Ras, are involved in tumorigenesis and progression of pleomorphic adenomas

The putative role of TP53 and p16(INK4A) tumor suppressor genes and Ras oncogenes in the development and progression of salivary gland neoplasias was studied in 28 cases of pleomorphic adenomas (PA), 4 cases of cystic adenocarcinomas, and 1 case of carcinoma ex-PA. Genetic and epigenetic alterations in the above genes were analyzed by Polymerase Chain Reaction/Single Strand Conformational Polymorphism (PCR/SSCP) and sequencing and by Methylation Specific-PCR (MS-PCR). Mutations in TP53 were found in 14% (4/28) of PAs and in 60% (3/5) of carcinomas. Mutations in H-Ras and K-Ras were identified in 4% (1/28) and 7% (2/28) of PAs, respectively. Only 20% (1/5) of carcinomas screened displayed mutations in K-Ras. p16(INK4A) promoter hypermethylation was found in 14% (4/28) of PAs and 100% (5/5) carcinomas. All genetic and epigenetic alterations were detected exclusively in the epithelial and transitional tumor components, and were absent in the mesenchymal parts. Our analysis suggests that TP53 mutations and p16(INK4A) promoter methylation, but not alterations in the H-Ras and K-Ras genes, might be involved in the malignant progression of PA into carcinoma.     

p16INK4a and p14ARF methylation as a potential biomarker for human bladder cancer

Promoter hypermethylation is one of the putative mechanisms underlying the inactivation of negative cell-cycle regulators. We examined whether the methylation status of p16(INK4a) and p14(ARF), genes located upstream of the RB and p53 pathway, is a useful biomarker for the staging, clinical outcome, and prognosis of human bladder cancer. Using methylation-specific PCR (MSP), we examined the methylation status of p16(INK4a) and p14(ARF) in 64 samples from 45 bladder cancer patients (34 males, 11 females). In 19 patients with recurrent bladder cancer, we examined paired tissue samples from their primary and recurrent tumors. The methylation status of representative samples was confirmed by bisulfite DNA sequencing analysis. The median follow-up duration was 34.3 months (range 27.0-100.1 months). The methylation rate for p16(INK4a) and p14(ARF) was 17.8% and 31.1%, respectively, in the 45 patients. The incidence of p16(INKa) and p14(ARF) methylation was significantly higher in patients with invasive (>or=pT2) than superficial bladder cancer (pT1) (p=0.006 and p=0.001, respectively). No MSP bands for p16(INK4a) and p14(ARF) were detected in the 8 patients with superficial, non-recurrent tumors. In 19 patients with tumor recurrence, the p16(INK4a) and p14(ARF) methylation status of the primary and recurrent tumors was similar. Of the 22 patients who had undergone cystectomy, 8 (36.4%) manifested p16(INKa) methylation; p16(INK4a) was not methylated in 23 patients without cystectomy (p=0.002). Kaplan-Meier analysis revealed that patients with p14(ARF) methylation had a significantly poorer prognosis than those without (p=0.029). This is the first study indicating that MSP analysis of p16(INK4a) and p14(ARF) genes is a useful biomarker for the pathological stage, clinical outcome, and prognosis of patients with bladder cancer.