Changes in the muscle strength and functional performance of healthy women with aging

BACKGROUND

Lower limbs antigravity muscles weakness and decreased functional ability have significant role in falling. The aim of this study was to find the effects of aging on muscle strength and functional ability, determining the range of decreasing strength and functional ability and relationship between them in healthy women.

METHODS

Across-section study was performed on 101 healthy women aged 21-80 years. The participants were divided into six age groups. The maximum isometric strength of four muscle groups was measured using a hand-held dynamometer bilaterally. The functional ability was measured with functional reach (FR), timed get up and go (TGUG), single leg stance (SLS), and stairs walking (SW) tests.

RESULTS

Muscle strength changes were not significant between 21-40 years of age, but decreased significantly thereafter. Also, there was a significant relationship between muscle strength and functional ability in age groups.

CONCLUSION

Both muscle strength and functional ability is reduced as a result of aging, but the decrease in functional ability can be detected earlier.

Temporary and permanent level shifts in distortion product otoacoustic emissions following noise exposure in an animal model

BACKGROUND

Noise-induced hearing loss (NIHL) is one of the most common occupational illnesses. Most of the studies on NIHL were conducted at high noise levels that people are rarely exposed to but in industries. The function of the outer hair cells (OHCs) is impaired after exposure to industrial noise. Distortion product otoacoustic emissions (DPOAEs) are useful in examination of noise-induced level shifts.

OBJECTIVE

To assess the function of OHCs by DPOAE temporary and permanent level shifts (TLSdp and PLSdp) in rabbits exposed to white noise at realistic levels typically found in industrial settings over a broad range of frequencies.

METHODS

12 albino rabbits were divided into two groups: the experimental group rabbits which were exposed to 95 dB SPL white noise at 500-8000 Hz for 8 hrs/day for 5 consecutive days, and the control group rabbits with no exposure to noise. The function of OHCs was examined by DPOAE level (Ldp) in different occasions. The study groups were compared for DPOAE temporary and permanent level shifts (TLSdp and PLSdp) to assess the effect of noise on OHCs function.

RESULTS

Noise-induced DPOAE levels (Ldp) were decreased up to 20.65 dB (on day 8) and 18.93 dB (on day 11) at 5888.50 Hz (p = 0.081). TLSdp and PLSdp were significantly decreased up to 17.99 dB and 16.27 dB, respectively in the experimental group. The most and least Ldp were significantly different (p<0.05); they occurred at 5888.50 and 588.00 Hz, respectively. There were significant differences between temporary and permanent threshold shift at various frequencies (p<0.05). These differences were mainly related to 5888.50 Hz compared to other frequencies in each ear (p<0.05).

CONCLUSION

DPOAEs are an attractive tool for obtaining information about small temporary or permanent threshold shifts, even when the pure tone audiogram is normal.

Effect of low-level laser therapy on healing of tenotomized Achilles tendon in streptozotocin-induced diabetic rats

Diabetes mellitus (DM) is associated with musculoskeletal damage. Investigations have indicated that healing of the surgically tenotomized Achilles tendon was considerably augmented following low-level laser therapy (LLLT) in non-diabetic, healthy animals. The aim of the present study was to evaluate the effect of LLLT on the Achilles tendon healing in streptozotocin-induced diabetic (STZ-D) rats via a biomechanical evaluating method. Thirty-three rats were divided into non-diabetic (n = 18) and diabetic (n = 15) groups. DM was induced in the rats by injections of STZ. The right Achilles tendons of all rats were tenotomized 1 month after STZ injections. The two experimental groups (n = 6 for each group) of non-diabetic rats were irradiated with a helium-neon (He-Ne) laser at 2.9 and 11.5 J/cm(2) for ten consecutive days. The two experimental groups of diabetic rats (n = 5 for each group) were irradiated with a He-Ne laser at 2.9 and 4.3 J/cm(2) for ten consecutive days. The tendons were submitted to a tensiometric test. Significant improvements in the maximum stress (MS) values (Newton per square millimeter) were found following LLLT at 2.9 J/cm(2) in both the non-diabetic (p = 0.031) and diabetic (p = 0.019) experimental groups when compared with their control groups. LLLT at 2.9 J/cm(2) to the tenotomized Achilles tendons in the non-diabetic and diabetic rats significantly increased the strength and MS of repairing Achilles tendons in our study.

IL-23 and IL-27 Levels in Macrophages Collected from Peripheral Blood of Patients with Healing Vs Non-Healing Form of Cutaneous Leishmaniasis

BACKGROUND

In this study the level of IL-23 and IL-27 produced by macrophages derived from peripheral blood mononuclear cell culture collected from patients with healing or non-healing form of cutaneous leishmaniasis lesion were compared before and after treatment with live Leishmania to explore whether IL-23 or IL-27 plays any role in healing process of cutaneous lesions induced by L. major.

METHODS

Twenty patients resident in Isfahan Province, with healing or non-healing form of cutaneous leishmaniasis lesion caused by Leishmania major participated in this study. In vitro productions of IL-23 and IL-27 by peripheral blood derived macrophages, before and after stimulation with live L. major (MRHO/IR/75/ER) promastigotes were evaluated using ELISA method. Patient with healing form of lesion received no treatment and patient with non-healing form of lesion received at least 2 courses of glucantime.

RESULTS

The mean production of IL-23 and IL-27 from macrophages of patients with healing form of lesion was significantly higher than patients with non-healing form of lesion. The levels of IL-23 and IL-27 in culture supernatants before and after stimulation in healing form of CL was significantly higher than non- healing form of CL (P < 0.001).

CONCLUSION

IL-23 and IL-27 might play a role in human leishmaniasis and further studies are needed to understand the role of IL-23 and IL-27 in leishmaniasis.

Schwann-like cell differentiation from rat bone marrow stem cells

INTRODUCTION

The main purpose of this study was differentiation of bone marrow stem cells (BMSCs) into Schwann-like cells and to determine the intensity of apoptosis in BMSCs during the differentiation process.

MATERIAL AND METHODS

Bone marrow stem cells were isolated from the femur of adult rats and the identity of the undifferentiated BMSCs was confirmed by the detection of specific cell surface markers. The BMSCs were differentiated by sequential administration of β-mercaptoethanol and all-trans-retinoic acid as pre-inducer factors and a mixture of forskolin, basic fibroblast growth factor, platelet-derived growth factor-AA and heregulin-b1 as inducer factors. The immunocytochemical properties of differentiated Schwann-like cells were examined at a specified time point. Reverse transcription-polymerase chain reaction (RT-PCR) was used to investigate the gene expression of the undifferentiated and differentiated BMSCs. Cell apoptosis and viability were assessed with annexin V and propidium iodide double staining and dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT) assay.

RESULTS

Immunocytochemistry staining and RT-PCR analysis revealed that the induced BMSCs exhibited Schwann cell-specific markers such as S-100, P75 and glial fibrillary acidic protein (GFAP) at the 14(th) day of differentiation. MTT assay and flow cytometry revealed that of the total BMSCs in the differentiation medium, 40% to 50% of the cells died by apoptosis, but the remaining cell population remained strongly attached to the substrate and differentiated.

CONCLUSIONS

These findings indicated that BMSCs could differentiate into Schwann-like cells. As a side effect of differentiation an increased cell death rate was noted and our findings indicate that the principle mode of cell death is by apoptosis.

Margin Status Influence on the Outcome of Patients Treated with Breast Conserving Surgery

BACKGROUND

Breast conserving surgery (BCS) followed by local radiotherapy is the standard treatment for early stage of breast cancer. Margin status may have an important impact on local recurrence and overall survival of patients treated with BCS, but this has not been defined adequately. In this study, we investigated the relationship between microscopic margins and outcome of BCS.

METHODS

Three hundred eighty four patients treated with BCS between 1999 and2010 were included in our study. All surgeries were performed by a single surgical team. Margins were defined as close if surgical margins were less than 2 mm, as free if surgical margins were more than 2 mm and as positive if malignant cells were present in one of the tissue edges. Demographic, clinical, and pathological factors as well as biological markers, recurrence, and survival rates were compared between the close and the free margins groups.

RESULTS

The mean age of patients at the time of diagnosis was 54.2 years. There were 34 (9%) recurrence cases and overall survival was 128.7 months and ten years survival rate was 81%. There was no significant difference between the close and the free margins groups in terms of demographic parameters, tumor characteristics, biological factors (estrogen and progesterone receptor status) and lymphovascular invasion. Also recurrence rate did not differ significantly between these two groups.

CONCLUSION

Our study indicates that there is no significant difference between the patients with close and the free margins in terms of treatment results. There is no clear consensus in the surgeons' community over the definition of acceptable margin width in BCS, so additional studies are required to find the right answer.

Neuroprotective properties of melissa officinalis L. Extract against ecstasy-induced neurotoxicity

OBJECTIVE

The aim of the present study was to investigate the neuroprotective effects of Melissa officinalis, a major antioxidant plant, against neuron toxicity in hippocampal primary culture induced by 3,4-methylenedioxymethamphetamine (MDMA) or ecstasy, one of the most abused drugs, which causes neurotoxicity.

MATERIALS AND METHODS

3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was used to assess mitochondrial activity, reflecting cell survival. Caspase-3 activity assay and Hoechst / propiedium iodide (PI) staining were done to show apoptotic cell death.

RESULTS

A high dose of ecstasy caused profound mitochondrial dysfunction, around 40% less than the control value, and increased apoptotic neuronal death to around 35% more than the control value in hippocampal neuronal culture. Co-treatment with Melissa officinalis significantly reversed these damages to around 15% and 20% respectively of the MDMA alone group, and provided protection against MDMA-induced mitochondrial dysfunction and apoptosis in neurons.

CONCLUSION

Melissa officinalis has revealed neuroprotective effects against apoptosis induced by MDMA in the primary neurons of hippocampal culture, which could be due to its free radical scavenging properties and monoamine oxidase (MAO) inhibitory effects.

Primary biliary cystadenocarcinoma mimicking a complicated hydatid cyst

Cystadenocarcinoma of the liver is a rare neoplasm that originates from hepatobiliary epithelium. Primary location of this tumor is generally intrahepatic and most cases are in the right hepatic lobe. Herein we present a case of intrahepatic cystadenocarcinoma in a 53-year-old man who had been followed up for 8 years as hydatic cyst disease of the liver. He was admitted to our hospital with jaundice and loss of appetite. Ultrasound and computed tomography showed a cystic lesion that looked like type II cyst hidatic. Thereafter magnetic resonance imaging revealed a cystic lesion associated with biliary tree. On diagnostic laparotomy peritoneal infiltrations were observed and pathologic examination revealed a biliary cystadenocarcinoma and peritonitis carcinomatosa was diagnosed. Unfortunately correct diagnosis was extremely late and no curative management was possible.

The contribution of founder mutations to early-onset breast cancer in French-Canadian women

In an ethnically-homogeneous population, it is valuable to identify founder mutations in cancer-predisposing genes. Founder mutations have been found in four breast-cancer-predisposing genes in French-Canadian breast cancer families. The frequencies of the mutant alleles have been measured neither in a large series of unselected breast cancer patients from Quebec, nor in healthy controls. These estimates are necessary to measure their contribution to the hereditary burden of breast cancer in Quebec and to help develop genetic screening policies which are appropriate for the province. We studied 564 French-Canadian women with early-onset invasive breast cancer who were treated at a single Montreal hospital. Patients had been diagnosed at age 50 or less, and were ascertained between 2004 and 2008. We screened all 564 patients for nine founder mutations: four in BRCA1, three in BRCA2 and one each in PALB2 and CHEK2. We also studied 6433 DNA samples from newborn infants from the Quebec City area to estimate the frequency of the nine variant alleles in the French-Canadian population. We identified a mutation in 36 of the 564 breast cancer cases (6.4%) and in 35 of 6443 controls (0.5%). In the breast cancer patients, the majority of mutations were in BRCA2 (54%). However, in the general population (newborn infants), the majority of mutations were in CHEK2 (54%). The odds ratio for breast cancer to age 50, given a BRCA1 mutation, was 10.1 (95% CI: 3.7-28) and given a BRCA2 mutation was 29.5 (95% CI: 12.9-67). The odds ratio for breast cancer to age 50, given a CHEK2 mutation, was 3.6 (95% CI: 1.4-9.1). One-half of the women with a mutation had a first- or second-degree relative diagnosed with breast or ovarian cancer. Thus, it can be concluded that a predisposing mutation in BRCA1, BRCA2, CHEK2 or PALB2 is present in approximately 6% of French-Canadian women with early-onset breast cancer. It is reasonable to offer screening for founder mutations to all French-Canadian women with breast cancer before age 50. The frequency of these mutations in the general population (0.5%) is too low to advocate population-based screening.

Effect of diabetes on median and dorsal raphe nuclei efferent fibers to CA3 hippocampal area in rat

Diabetes Mellitus (DM) is one of the most important metabolic disease causes in many side effects. The decrease of mental abilities and even some form of dementia followed prolonged diabetes has been reported. There are evidences that show hippocampus might be the site of neural involvement in patients with dementia followed diabetes. As hippocampus received main serotonergic efferents from brain stem raphe nuclei include dorsal raphe nucleus (DRN) and median raphe nucleus (MRN), it is possible that these efferent affected by diabetes. We used adult male Wistar rat in this study. Diabetes was induced by i.p. injection of streptozotocin (STZ). After 2, 4 and 6 months, HRP tracing were done for the efferent from DRN & MRN to CA3 of hippocampus. HRP Positive neuron of DRN & MRN and also the distribution of these cells were study by light microscopy. Statistical analysis was done by SPSS software. Microscopic study clearly showed significant decrease in HRP positive cells population in DRN & MRN after prolonged diabetes. Based on our finding ,the changes in the neural connection between serotonergic nuclei and hippocampus followed diabetes might be one of the reasons for dementia in these patients.

The Contribution of Founder Mutations to Early-Onset Breast Cancer in French-Canadian Women

Background: In an ethnically-homogeneous population, it is valuable to identify founder mutations in cancer-predisposing genes. Founder mutations have been found in four breast cancer predisposing genes in French-Canadian breast cancer families. The frequencies of the mutant alleles have not been measured in a large series of unselected breast cancer patients from Quebec, nor in healthy controls. These estimates are necessary to measure their contribution to the hereditary burden of breast cancer in Quebec and to help develop genetic screening policies which are appropriate for the province.Methods: We studied 564 French-Canadian women with early-onset invasive breast cancer who were treated at a single Montreal hospital. Patients had been diagnosed at age 50 or less, and were ascertained between 2004 and 2008. We screened all 564 patients for nine founder mutations; four in BRCA1, three in BRCA2 and one each in PALB2 and CHEK2. We also studied 6433 DNA samples from newborn infants from the Quebec City area to estimate the frequency of the nine variant alleles in the French-Canadian population.Results: We identified a mutation in 36 of the 564 breast cancer cases (6.4%) and in 35 of 6443 controls (0.5%). In the breast cancer patients, the majority of mutations were in BRCA2 (54%). However, in the general population (newborn infants), the majority of mutations were in CHEK2 (54%). The odds ratio for breast cancer to age 50, given a BRCA1 mutation was 10.1 (95% CI: 3.7 to 28) and given a BRCA2 mutation was 29.5 (95% CI: 12.9 – 67). The odds ratio for breast cancer to age 50, given a CHEK2 mutation was 3.6 (95% CI: 1.4 – 9.1). One-half of the women with a mutation had a first or second-degree relative diagnosed with breast or ovarian cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 902.

A gel electrophoresis method for detection of mitochondrial DNA mutation (3243 tRNALeu (UUR)) applied to a Norwegian family with diabetes mellitus and hearing loss

Blood cells of selected patients from a large Norwegian family with maternally transmitted diabetes mellitus, hearing loss and muscular dysfunction were screened for possible A3243G mutation tRNA(Leu (UUR)) in mitochondrial DNA. We selected 7 patients from 3 of the 4 generations of the family and 10 unrelated healthy control subjects for mutation analysis using denaturing gradient gel electrophoresis (DGGE) and both manual and automated DNA sequencing. The A3243G mutation was found in peripheral blood cells of all 7 patients, but in none of the controls. The mutation was in the form of heteroplasmy and the amount of mutant DNA was found to be between 10% and 35% of total mtDNA in individual patients. This is the first report of a Norwegian family with maternally inherited diabetes and hearing loss carrying the A3243G mutation in mitochondrial DNA.

A double-blind, randomized trial of low-dose topiramate vs propranolol in migraine prophylaxis

OBJECTIVE

To assess the efficacy and safety of low-dose topiramate in migraine prophylaxis vs propranolol.

PATIENTS AND METHODS

A randomized, double-blind, clinical trial including 62 patients with frequent migraine headaches (> or = 3 attacks per month) was performed for a period of 8 weeks. The patients were randomly divided into two treatment groups - treated by topiramate 50 mg/day and propranolol 80 mg/day, respectively. The patients were assessed at 0, 4, and 8 weeks of the study. Results - The topiramate group showed a reduction in the mean (+/-SD) of monthly migraine frequency from 6.07 (+/-1.89) to 1.83 (+/-1.39) episodes per month, headache intensity from 7.1 (+/-1.45) to 3.67 (+/-2.1) based on the Visual Analog Scale, and headache duration from 16.37 (+/-7.26) to 6.23 (+/-5.22) hours (P < 0.001). In the patients treated with propranolol, the mean (+/-SD) of monthly headache frequency declined from 5.83 (+/-1.98) to 2.2 (+/-1.67) per month, headache intensity lessened from 6.43 (+/-1.6) to 4.13 (+/-1.94) and headache duration decreased from 15.10 (+/-6.84) to 7.27 (+/-6.46) h (P < 0.001).

CONCLUSION

This study demonstrated that both low-dose topiramate and propranolol could significantly reduce migraine headache frequency, intensity, and duration. However, compared with propranolol, low-dose topiramate showed better results.

Smoking initiation among Iranian adolescents: a qualitative study

In response to the need for effective tobacco prevention programmes in the Islamic Republic of Iran, the present study sought to determine the major risk factors for initiation of smoking by adolescents. A content analysis with a qualitative approach was conducted through 22 in-depth interviews, 2 focus groups (4 and 6 participants in each group) and 30 narratives. The following 3 themes emerged from the analysis as risk factors for initiating smoking by adolescents: personal factors, social factors and beliefs about smoking. Based on these findings, it is recommended that prevention activities should be embedded in a comprehensive approach which aims to change the smoking and parenting behaviour of parents and teachers, and at creating non-smoking policies in schools and other places where young people congregate.

Balance problems after unilateral lateral ankle sprains

Abstract-Ankle ligament injury is the most common injury in athletic activities. This study examined balance problems in athletes with acute lateral ankle sprains. Thirty male athletes aged 20 to 35 years with right dominant side and traumatic ankle sprain were recruited through simple nonprobability sampling. We measured the sway index and limits of stability with the Biodex Balance System under different conditions. Functional balance was evaluated with two clinical tests: the Functional Reach Test and the Star-Excursion Balance Test. The results showed that balance ability in patients with acute lateral ankle sprain was significantly weaker under closed- versus open-eye conditions. Symmetry of weight-bearing on involved and sound limb in bilateral standing was not significantly different, but weight-bearing on the nondominant limb was significantly higher than on the dominant limb. We can conclude that balance problems occur after acute ankle sprains because of proprioception deficits and that the unconscious (reflexive) aspect of proprioception is more severely affected than the conscious (voluntary) aspect.

The effects of simvastatin on functional recovery of rat reperfused sciatic nerve

This study evaluated the effectiveness of simvastatin in protecting sciatic nerve from ischemia-reperfusion (I/R) injury using the model of experimental nerve ischemia. Sixty adult male Sprague-Dawley rats weighing 250-300 g were used. They were divided into ten groups (N = 6 per group). We used ischemia model in these groups. All ischemia groups were rendered ischemic for 3 h. Then followed by reperfusion durations of zero time (0 hR), 3 h (3 hR), 7 days (7 dR), 14 days (14 dR). The treatment group received intravenous simvastatin (1 mg kg(-1)) 1 h before ischemia, while the control group received an equal volume of intravenous vehicle at the same time schedule and route. Behavioral data were obtained immediately before euthanasia. The score was based on coordination, racing reflex, toe spread and reaction to pinch. In simvastatin treated I/R rats we had increase in functional recovery. In conclusion, pre-ischemic administration of simvastatin exhibits neuroprotective properties in I/R nerve injury.

Different organization of base excision repair of uracil in DNA in nuclei and mitochondria and selective upregulation of mitochondrial uracil-DNA glycosylase after oxidative stress

Oxidative stress in the brain may cause neuro-degeneration, possibly due to DNA damage. Oxidative base lesions in DNA are mainly repaired by base excision repair (BER). The DNA glycosylases Nei-like DNA glycosylase 1 (NEIL1), Nei-like DNA glycosylase 2 (NEIL2), mitochondrial uracil-DNA glycosylase 1 (UNG1), nuclear uracil-DNA glycosylase 2 (UNG2) and endonuclease III-like 1 protein (NTH1) collectively remove most oxidized pyrimidines, while 8-oxoguanine-DNA glycosylase 1 (OGG1) removes oxidized purines. Although uracil is the main substrate of uracil-DNA glycosylases UNG1 and UNG2, these proteins also remove the oxidized cytosine derivatives isodialuric acid, alloxan and 5-hydroxyuracil. UNG1 and UNG2 have identical catalytic domain, but different N-terminal regions required for subcellular sorting. We demonstrate that mRNA for UNG1, but not UNG2, is increased after hydrogen peroxide, indicating regulatory effects of oxidative stress on mitochondrial BER. To examine the overall organization of uracil-BER in nuclei and mitochondria, we constructed cell lines expressing EYFP (enhanced yellow fluorescent protein) fused to UNG1 or UNG2. These were used to investigate the possible presence of multi-protein BER complexes in nuclei and mitochondria. Extracts from nuclei and mitochondria were both proficient in complete uracil-BER in vitro. BER assays with immunoprecipitates demonstrated that UNG2-EYFP, but not UNG1-EYFP, formed complexes that carried out complete BER. Although apurinic/apyrimidinic site endonuclease 1 (APE1) is highly enriched in nuclei relative to mitochondria, it was apparently the major AP-endonuclease required for BER in both organelles. APE2 is enriched in mitochondria, but its possible role in BER remains uncertain. These results demonstrate that nuclear and mitochondrial BER processes are differently organized. Furthermore, the upregulation of mRNA for mitochondrial UNG1 after oxidative stress indicates that it may have an important role in repair of oxidized pyrimidines.

Oral adjuvant treatment choices and local recurrence risk in early stage breast cancer

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Background: Among women (W) with early-stage breast cancer (BC) treated with lumpectomy and radiation therapy (RT), those who also receive oral adjuvant therapy (OAT) have a lower risk of local recurrence (LR). The purpose of this study was to evaluate the associations of age (A), race/ethnicity (RE), education (E), socioeconomic status (SS), LR rate, and knowledge about potential side effects (SE) with W’s willingness to receive OAT. Methods: Between 6/05 and 9/05, we asked W with (+) and without (−) BC to participate in an IRB-approved survey. The survey questionnaire presented W with clinical vignettes including information about RT ± 5 years of OAT and the LR and SE associated with treatment options. It then asked W to choose between the treatment options and to rate them, using a time trade-off method, given LR and SE. Results: The distribution of the 161 respondents (55 (+)BC and 106 (−)BC) by A, RE, E, SS is shown in the table below. A and RE were associated with a W’s choice of combined modality treatment (CMT) consisting of RT and OAT, to decrease the risk of LR (p < 0.009 and p < 0.056). Stratified analysis showed an association between CMT and E (p < 0.006) in W (+)BC; A (p < 0.04) and SS (p < 0.04) were associated with CMT choice when SE were described. In W (−) BC, RE (p < 0.02) and SS (p < 0.04) were associated with CMT choice when SE were described. Compared to W who had used oral contraceptive agents (OCA), women who did not use OCA were 45% less likely to trade time to decrease their risk of LR by taking OAT when told about similar SE between OCA and OAT (OR = 0.55, 95% CI 0.28, 1.09), but this association was not statistically significant. Conclusions: W of various A, RE, E and SS who were given information about treatment choices with LR rates chose therapies that gave them the best chance of disease-free survival. For W (+) BC history, level of E significantly influenced the choice to proceed with CMT. A, RE and SS influenced CMT choice when SE were described. W who had used OCA in the past may have been less concerned than others about potential side effects of OAT.

[Table: see text]

No significant financial relationships to disclose.

Herpes Simplex Virus Type II Infection of Ileum Mesothelium: A Case Report and Review of the Literature

Disseminated herpes simplex virus (HSV) infection usually manifests in the immunocompromised. However, anecdotal examples of visceral HSV disease and viremia have complicated type I diabetes. A case of a 53-year-old type I diabetic patient with bowel obstruction one week subsequent to bronchitis is reported. At laparotomy, a perforated segment of ileum was associated with an adhesive peritoneal band. HSV cytopathic atypia and HSV immunohistochemical staining were confined to fibrocytes and mesothelial cells without involvement of the epithelium. Dissemination of symptomatic HSV pneumonia was verified by histology, immunohistochemistry, in situ hybridization, polymerase chain reaction and direct fluorescence antibody. Intravenous acyclovir resolved symptoms. This is a novel documentation of HSV complicating ileal adhesive band disease. Furthermore, this case indicates that the HSV cytopathic effect is not unique to the epithelium. Disseminated infection can manifest in myofibrocytes and mesothelium, distinguishing it from standard epithelial atypia of localized HSV infection.

Properties and functions of human uracil-DNA glycosylase from the UNG gene

The human UNG-gene at position 12q24.1 encodes nuclear (UNG2) and mitochondrial (UNG1) forms of uracil-DNA glycosylase using differentially regulated promoters, PA and PB, and alternative splicing to produce two proteins with unique N-terminal sorting sequences. PCNA and RPA co-localize with UNG2 in replication foci and interact with N-terminal sequences in UNG2. Mitochondrial UNG1 is processed to shorter forms by mitochondrial processing peptidase (MPP) and an unidentified mitochondrial protease. The common core catalytic domain in UNG1 and UNG2 contains a conserved DNA binding groove and a tight-fitting uracil-binding pocket that binds uracil only when the uracil-containing nucleotide is flipped out. Certain single amino acid substitutions in the active site of the enzyme generate DNA glycosylases that remove either thymine or cytosine. These enzymes induce cytotoxic and mutagenic abasic (AP) sites in the E. coli chromosome and were used to examine biological consequences of AP sites. It has been assumed that a major role of the UNG gene product(s) is to repair mutagenic U:G mispairs caused by cytosine deamination. However, one major role of UNG2 is to remove misincorporated dUMP residues. Thus, knockout mice deficient in Ung activity (Ung-/- mice) have only small increases in GC-->AT transition mutations, but Ung-/- cells are deficient in removal of misincorporated dUMP and accumulate approximately 2000 uracil residues per cell. We propose that BER is important both in the prevention of cancer and for preserving the integrity of germ cell DNA during evolution.

Chemosensitization of human renal cell cancer using antisense oligonucleotides targeting the antiapoptotic gene clusterin

BACKGROUND

Renal cell cancer (RCC) is a chemoresistant disease with no active chemotherapeutic agent achieving objective response rates higher than 15%. Clusterin is a cell survival gene that increases in human renal tubular epithelial cells after various states of injury and disease. Downregulation of clusterin, using antisense oligonucleotides (ASO), has recently been shown to increase chemosensitivity in several prostate cancer models. The objectives in this study were to evaluate clusterin expression levels in human RCC and normal kidney tissue, and to test whether clusterin ASO could also enhance chemosensitivity in human RCC Caki-2 cells both in vitro and in vivo.

METHODS

Immunohistochemical staining was used to characterize clusterin expression in 67 RCC and normal kidney tissues obtained from radical nephrectomy specimens. Northern blot analysis was used to assess changes in clusterin mRNA expression after ASO and paclitaxel treatment. The effects of combined clusterin ASO and paclitaxel treatment on Caki-2 cell growth was examined using an MTT assay. Athymic mice bearing Caki-2 tumors were treated with clusterin ASO alone, clusterin ASO plus paclitaxel, and mismatch control oligonucleotides plus paclitaxel, over a period of 28 days with measurement of tumor volumes once weekly over 8 weeks.

RESULTS

Immunohistochemistry of normal and malignant kidney tissue sections of 67 patients demonstrated positive clusterin staining for almost all RCC (98%) and an overexpression, compared to normal tissue, in a majority of RCC (69%). Clusterin ASO, but not mismatch control oligonucleotides, decreased clusterin mRNA expression in Caki-2 cells in a dose-dependent and sequence-specific manner. Pretreatment of Caki-2 cells with clusterin ASO significantly enhanced chemosensitivity to paclitaxel in vitro. Characteristic apoptotic DNA laddering was observed after combined treatment with ASO plus paclitaxel, but not with either agent alone. In vivo administration of clusterin ASO plus paclitaxel acted synergistically to increase apoptosis and significantly delay Caki-2 tumor growth, compared to mismatch control oligonucleotide plus paclitaxel. In addition, TUNEL staining revealed increased apoptotic cells in tumors treated with clusterin ASO plus paclitaxel compared to treatment with either clusterin ASO or paclitaxel alone.

CONCLUSION

These findings confirm that the use of clusterin ASO may be a feasible strategy to enhance chemosensitivity for patients with advanced RCC.

Sequence variation in the human uracil-DNA glycosylase (UNG) gene

Spontaneous deamination of cytosine results in a premutagenic G:U mismatch that may result in a GC-->AT transition during replication. The human UNG-gene encodes the major uracil-DNA glycosylase (UDG or UNG) which releases uracil from DNA, thus, initiating base excision repair to restore the correct DNA sequence. Bacterial and yeast mutants lacking the homologous UDG exhibit elevated spontaneous mutation frequencies. Hence, mutations in the human UNG gene could presumably result in a mutator phenotype. We screened all seven exons including exon-intron boundaries, both promoters, and one intron of the UNG gene and identified considerable sequence variation in cell lines derived from normal fibroblasts and tumour tissue. None of the sequence variants was accompanied by significantly reduced UDG activity. In the UNG gene from 62 sources, we identified 12 different variant alleles, with allele frequencies ranging from 0.01 to 0.23. We identified one variant allele per 3.8kb in non-coding regions, but none in the coding region of the gene. In promoter B we identified four different variants. A substitution within an AP2 element was observed in tumour cell lines only and had an allele frequency of 0.10. Introduction of this substitution into chimaeric promoter-luciferase constructs affected transcription from the promoter. UDG-activity varied little in fibroblasts, but widely between tumour cell lines. This variation did not however correlate with the presence of any of the variant alleles. In conclusion, mutations affecting the function of human UNG gene are seemingly infrequent in human tumour cell lines.

Post-replicative base excision repair in replication foci

Base excision repair (BER) is initiated by a DNA glycosylase and is completed by alternative routes, one of which requires proliferating cell nuclear antigen (PCNA) and other proteins also involved in DNA replication. We report that the major nuclear uracil-DNA glycosylase (UNG2) increases in S phase, during which it co-localizes with incorporated BrdUrd in replication foci. Uracil is rapidly removed from replicatively incorporated dUMP residues in isolated nuclei. Neutralizing antibodies to UNG2 inhibit this removal, indicating that UNG2 is the major uracil-DNA glycosylase responsible. PCNA and replication protein A (RPA) co-localize with UNG2 in replication foci, and a direct molecular interaction of UNG2 with PCNA (one binding site) and RPA (two binding sites) was demonstrated using two-hybrid assays, a peptide SPOT assay and enzyme-linked immunosorbent assays. These results demonstrate rapid post-replicative removal of incorporated uracil by UNG2 and indicate the formation of a BER complex that contains UNG2, RPA and PCNA close to the replication fork.