An improved method for isolation of RNA from rat femur

BACKGROUND

RNA isolation from ossified bone is a difficult and time-consuming process which often results in poor recovery of RNA. The yield is limited and might not be suitable for gene quantification studies by real time PCR.

METHODOLOGY

The present study demonstrates RNA extraction from rat femur utilizing the silica column along with the trizol reagent. Quality of RNA was assessed by agarose gel analysis and its suitability for real-time PCR analysis was determined by β-actin Ct values.

RESULTS

The RNA isolated using silica columns in conjugation with trizol reagent resulted in higher yield of RNA and purity (A260/280=2.04; yield =1545.73 µg/ml) compared to the trizol method alone (A260/280=1.85; yield =571.2 µg/ml). Ct value of β actin obtained from RNA isolated by trizol method was higher than the Ct value obtained by trizol in conjugation with the column method (31.41 and 15.41 respectively).

CONCLUSION

Combination of trizol along with silica column resulted in better quality and improved yield of RNA suitable for gene quantification by Real time PCR.

Transplantation Efficacy of Human Ciliary Epithelium Cells from Fetal Eye and Lin-ve Stem Cells from Umbilical Cord Blood in the Murine Retinal Degeneration Model of Laser Injury

A number of degenerative conditions affecting the neural retina including age-related macular degeneration have no successful treatment, resulting in partial or complete vision loss. There are a number of stem cell replacement strategies for recovery of retinal damage using cells from variable sources. However, literature is still deficit in the comparison of efficacy of types of stem cells. The purpose of the study was to compare the therapeutic efficacy of undifferentiated cells, i.e., lineage negative stem cells (Lin-ve SC) with differentiated neurosphere derived from ciliary epithelium (CE) cells on retinal markers associated with laser-induced retinal injury. Laser-induced photocoagulation was carried out to disrupt Bruch’s membrane and retinal pigmented epithelium in C57BL/6 mouse model. Lineage negative cells were isolated from human umbilical cord blood, whereas neurospheres were derived from CE of post-aborted human eyeballs. The cells were then transplanted into subretinal space to study their effect on injury. Markers of neurotropic factors, retina, apoptosis, and proliferation were analyzed after injury and transplantation. mRNA expression was also analyzed by real-time polymerase chain reaction at 1 week, and 3-month immunohistochemistry was evaluated at 1-week time point. CE cell transplantation showed enhanced differentiation of rods and retinal glial cells. However, Lin-ve cells exerted paracrine-dependent modulation of neurotrophic factors, which is possibly mediated by antiapoptotic and proliferative effects. In conclusion, CE transplantation showed superior regenerative outcome in comparison to Lin-ve SC for rescue of artificially injured rodent retinal cells. It is imperative that this source for transplantation may be extensively studied in various doses and additional retinal degeneration models for prospective clinical applications.

Human Fetal Pigmented Ciliary Epithelium Stem Cells have Regenerative Capacity in the Murine Retinal Degeneration Model of Laser Injury

BACKGROUND

Retinal degeneration and related eye disorders have limited treatment interventions. Since stem cell therapy has shown promising results, ciliary epithelium (CE) derived stem cells could be a better choice given the fact that cells from eye niche can better integrate with the degenerating retina, rewiring the synaptic damage.

OBJECTIVE

To test the effect of human fetal pigmented ciliary epithelium-derived neurospheres in the mouse model of laser-induced retinal degeneration.

METHODS

C57 male mice were subjected to retinal injury by Laser photocoagulation. Human fetal pigmented ciliary epithelium was obtained from post-aborted human eyeballs and cultured with epidermal growth factor (rhEGF) and fibroblast growth factor (rhFGF). The six day neurospheres were isolated, dissociated and transplanted into the subretinal space of the laser injured mice at the closest proximity to Laser shots. Mice were analyzed for functional vision through electroretinogram (ERG) and sacrificed at 1 week and 12 week time points. Retinal, Neurotropic, Apoptotic and proliferation markers were analysed using real-time polymerase chain reaction (PCR).

RESULTS

The CE neurospheres showed an increase in the expression of candidate genes analyzed in the study at 1 week time point, which sustained for longer time point of 12 weeks.

CONCLUSION

We showed the efficacy of human CE cells in the regeneration of retinal degeneration in murine model for the first time. CE cells need to be explored comprehensively both in disease and degeneration.

Conventional radiotherapy and intensity-modulated radiotherapy in carcinoma vulva: An experience from a tertiary medical center of India

Context

Vulvar cancer is one of the uncommon gynecological malignancies. Multimodality treatment with surgery, radiotherapy, and chemotherapy are required for treatment of the disease.

Aims

The aim of the study was to evaluate clinical outcome in patients of carcinoma vulva, treated at our institution.

Subjects and Methods

This was a retrospective-cohort study done in 50 patients with squamous cell carcinoma of the vulva, treated at our institution from January 2008 to December 2014. Data were analyzed on the basis of age, stage, type of treatment received, and treatment-related toxicity. Disease-free survival and overall survival were estimated.

Statistical Analysis Used

Kaplan-Meier survival analysis and Chi-square test were used for statistical analysis.

Results

Majority of the patients (52%) had presented with Stage III disease. Thirty-six of 50 patients underwent surgery: simple vulvectomy - 2, radical vulvectomy - 34, bilateral inguinal lymph node dissection was done in 32 patients, and 1 patient underwent ipsilateral-inguinal lymph node dissection. Among 40 patients who received radiotherapy and eight patients received palliative radiotherapy. Seventeen patients underwent intensity-modulated radiotherapy (IMRT) and 15 patients received conventional radiotherapy. Significantly less Grade 2 or more skin toxicity (P = 0.003) observed in patients who underwent IMRT. Among non-IMRT group, eight patients required treatment break during radiation. At a median follow-up time of 25.5 months, median overall survival was 31 months and median disease-free survival was 25 months. About 42% patients were alive and free of disease at last follow-up.

Conclusions

Modified radical vulvectomy with inguinal lymph node dissection followed by radiotherapy is the mainstay of management of locally advanced carcinoma vulva. Using IMRT, we could minimize the treatment related radiation toxicity and treatment breaks.

Resveratrol restores the level of key inflammatory cytokines and RANKL/OPG ratio in the femur of rat osteoporosis model

Resveratrol's effect on bone mineral density (BMD) and expression of cytokines in ovariectomized rats (postmenopausal osteoporosis model) was studied. The study was conducted on 3-month-old Sprague-Dawley rats that were (a) sham-operated, (b) ovariectomized, (c) ovariectomized and treated with β-estradiol (487.5 µg/kg weight/day), and (d) ovariectomized and treated with resveratrol (625 µg/Kg body weight/day). The treatment was for 4 weeks. After sacrifice BMD and gene expression (RANKL, OPG, IL-23, and IL-17A, IL-1β, and TNFα) were measured in tibia and femur respectively. Resveratrol could restore RANKL/OPG ratio, slightly increase BMD, and moderately but significantly reduce IL-23, IL-17A, IL-1β, and TNF-α cytokine expression levels.

Determination of an optimal dosing schedule for combining Irinophore C™ and temozolomide in an orthotopic model of glioblastoma

Our laboratory reported that Irinophore C™ (IrC™; a lipid-based nanoparticulate formulation of irinotecan) is effective against an orthotopic model of glioblastoma (GBM) and that treatment with IrC™ was associated with vascular normalization within the tumor. Here, the therapeutic effects of IrC™ when used in combination with temozolomide (TMZ) in concurrent and sequential treatment schedules were tested. It was anticipated that IrC™ engendered vascular normalization would increase the delivery of TMZ to the tumor and that this would be reflected by improved treatment outcomes. The approach compared equally efficacious doses of irinotecan (IRN; 50 mg/kg) and IrC™ (25 mg/kg) in order to determine if there was a unique advantage achieved when combining TMZ with IrC™. The TMZ sensitive U251MG(O) cell line (null expression of O-6-methylguanine-DNA methyltransferase (MGMT)) modified to express the fluorescent protein mKate2 was inoculated orthotopically into NOD.CB17-SCID mice and treatment was initiated 14 days later. Our results demonstrated that IrC™ and TMZ administered concurrently resulted in optimal treatment outcomes, with 50% long term survivors (>180 days) in comparison to 17% long term survivors in animals treated with IRN and TMZ or TMZ alone. Indeed, the different treatments resulted in a 353%, 222% and 280% increase in median survival time (MST) compared to untreated animals for, respectively, IrC™ combined with TMZ, IRN combined with TMZ, and TMZ alone. When TMZ was administered after completion of IRN or IrC™ dosing, an increase in median survival time of 167-174% was observed compared to untreated animals and of 67% and 74%, respectively, when IRN (50 mg/kg) and IrC™ (25mg/kg) were given as single agents. We confirmed in these studies that after completion of the Q7D×3 dosing of IrC™, but not IRN, the tumor-associated vascular was normalized as compared to untreated tumors. Specifically, reductions in the fraction of collagen IV-free CD31 staining (p<0.05) and reductions in tumor vessel diameter were observed in tumors from IrC™-treated animals when compared to tumors from untreated or IRN treated animals. Analysis by transmission electron microscopy of the ultra-structure of tumors from IrC™-treated and untreated animals revealed that tumor-associated vessels from treated animals were smaller, more organized and exhibited a morphology comparable to normal blood vessels. In conclusion, optimal treatment outcomes were achieved when IrC™ and TMZ were administered concurrently, whereas IrC™ followed by TMZ treatment given sequentially did not confer any therapeutic advantage.

Scrub typhus in pregnancy: a case series

Scrub typhus, an acute febrile illness caused by Rickettsia and transmitted by mites, is a re-emerging endemic zoonosis in the Asia Pacific region. It is an uncommon entity and very few cases of this disease in pregnant women have been reported. We present a series of six such cases collected over 1 year with poor feto-maternal outcome in 50%.

Mean gestation at delivery and histological chorioamnionitis correlates with early-onset neonatal sepsis following expectant management in pPROM

This prospective observational study was carried out in India among 100 women with preterm pre-labour rupture of membranes (pPROM) between 26(0/7)-33(0/7) weeks on expectant management in order to correlate early-onset neonatal sepsis (EONS) with various features of chorioamnionitis. The incidence of pPROM during the study period of 1.5 years was 7%. The mean gestation at pPROM was 30(6/7) ± 1.8 weeks and at delivery was 32(1/7) ± 1 weeks. Features of chorioamnionitis in the form of clinical, microbiological, histological or a combination of these were observed in 70/100 women. Clinical chorioamnionitis was seen in 16%, bacterial isolates were present in 30% on cervical swab and in 39% on placental membrane culture and 19% had histological chorioamnionitis. EONS was present in 23/97 (24%). Clinical chorioamnionitis (p = 0.069), bacterial isolates on cervical swab (p = 0.56) or placental membranes (p = 0.39) were not found to predict EONS; whereas histological chorioamnionitis (p = 0.002) and lower gestation at delivery (p = 0.013) were significantly associated with EONS.

Vascular endothelial growth factor (VEGF) induced proliferation of human fetal derived ciliary epithelium stem cells is mediated by jagged-N cadherin pathway

The pigmented ciliary epithelium (PCE) of mammalian eye harbors resident population of stem cells that lie in apposition with endothelial cells which release vascular endothelial growth factor (VEGF) that may influence the fate and function of these stem cells in ways that remain unclear. We examined the role of VEGF in proliferation of PCE stem cells and expression of Notch, Jagged, N-Cadherin and β-Catenin which are known to maintain proliferation state of neural stem cells. We cultured human PCE cells obtained from 12-20 weeks old fetal eyes. The neurospheres were analyzed for the proliferation capacity of PCE stem cells in presence of VEGF on 3,6 and 9 day. Real time PCR was used to quantitate the mRNA expression of above mentioned genes on PCE derived neurospheres on 3,6 and 9 day. We found increased number of neurospheres when PCE stem cells were stimulated with VEGF along with epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) than EGF and bFGF. BrdU immunostaining was done to analyze the proliferation of CE cells and presence of neural and retinal progenitor markers such as Nestin and Pax6 were also investigated. An increased Notch and Jagged mRNA was observed on 6(th) day in VEGF, EGF and bFGF treated PCE cells as compared to 0,3 and 9 day. A similar pattern was noticed with N-cadherin and β-catenin mRNA levels. These findings may clarify the role of VEGF on PCE stem cell proliferation with possible involvement of Notch, Jagged, N-cadherin and β-Catenin. The data may suggest importance of harvesting 6(th) day neurospheres for transplantation purposes in preclinical investigations pertaining to retinal degenerative diseases, however, additional studies are needed to substantiate the findings.

Intrapartum antibiotics and risk factors for early onset sepsis

OBJECTIVE

To determine the independent risk factors for early onset neonatal sepsis (EONS) in a setting where the policy is to use intrapartum antibiotic prophylaxis (IAP) for known risk factors.

DESIGN

Prospective cohort study.

SETTING

Level III neonatal unit in a developing country.

PATIENTS

Consecutive mother-infant dyads (gestation < or =34 weeks) with no major neonatal malformations.

INTERVENTIONS

Thirteen putative maternal and neonatal risk factors and use of IAP were assessed. Neonates were followed until 72 h of life for signs of EONS. Blood cultures were drawn on clinical suspicion of EONS and/or prior to starting prophylactic antibiotics for high risk asymptomatic neonates.

MAIN OUTCOME

Culture-proven EONS (onset at <72 h).

RESULTS

601 mother-infant dyads were enrolled (mean (SD) gestation=31.8 (2) weeks; mean (SD) birth weight 1559.4 (452) g). The best fitted multivariable logistic regression model had six independent risk factors (adjusted OR (95% CI)): vaginal examinations > or =3 (9.5 (3 to 31)), clinical chorioamnionitis (8.8 (2 to 43)), birth weight <1500 g (2.8 (2 to 5)), male sex (2.7 (2 to 5)), gestation <30 weeks (2 (1 to 4)) and no IAP (2 (1.04 to 4)). Regression coefficients were converted into scores of 6, 6, 3, 3, 2 and 2, respectively. Internal prediction accuracy was 86.5% and c statistic was 0.75 (95% CI 0.70 to 0.81, p<0.001).

CONCLUSIONS

Vaginal examinations > or =3, clinical chorioamnionitis, birth weight <1500 g, male sex, gestation <30 weeks and no intrapartum antibiotics were independent risk factors for EONS among preterm infants of < or =34 weeks' gestation.

Obstetric morbidity and the diagnostic dilemma in pregnancy in rudimentary horn: retrospective analysis

BACKGROUND

Pregnancy in rudimentary horn of uterus, a form of ectopic gestation, is associated with significant rates of morbidity and mortality. Despite the recent advances in the ultrasonography, diagnosis of cornual pregnancy still remains elusive; with confirmatory diagnosis usually made during laparotomy. The aim of the present study is to analyze the obstetric implications and the diagnostic dilemma of rudimentary horn pregnancy.

MATERIALS AND METHODS

Records of women diagnosed with ectopic pregnancy in the rudimentary horn, during the years 2004 to 2008, managed in a referral hospital in northern India; were reviewed for their diagnostic difficulties and the associated morbidity.

RESULTS

During the four year study period, rudimentary horn pregnancies accounted for 12 pregnancies. Non communicating horn accounted for 75% of the cases. The mean age of women at presentation was 26 +/- 5.11 years and the period of gestation at diagnosis varied between 10 and 34 weeks. Preruputure diagnosis was possible only in two cases and sensitivity of ultrasonographic diagnosis was 33.3%. Laprotomy with excision of rudimentary horn and salpingectomy was done in all cases. Multiple blood transfusions were required in 83.3% of women.

CONCLUSION

Management of pregnancy in a rudimentary uterine horn continues to be a challenge to this day. Maintaining a higher degree of alertness, especially in high risk groups by emergency staff is required to prevent the morbidity, as they may present with acute uterine rupture in pregnancy.

Amelioration of chronic relapsing experimental autoimmune encephalomyelitis (cr-eae) using thymoquinone - biomed 2009

Axonal damage, demylination and inflammation of the central nervous system are the major pathological features of the human multiple sclerosis (MS). MS is thought to be due to abnormal T cell mediated immune response. Oxidative stress plays an important role in the advancement of MS. The management of oxidative stress by outlining central role of reduced glutathione. In our experiment we used Experimental autoimmune encephalomyelitis (EAE) animal model that mimic human MS and tested the effect of Thymoquinone (TQ), an oil constituent of Nigella Sativa also known as black seed. Thirty female mice of strain C57BL/6J and aged between 6 to 12 weeks were placed into 3 groups of 10 and were given Myelin Oligodendrocyte Glycoprotein (MOG) subcutaneously (SC) to induce EAE. Group A was the control group. Group B received MOG (SC) and TQ intraperiotoneally (IP) from day 1 till day 50. Group C received MOG (SC) and TQ (IP) on the appearance of first sign and symptoms of chronic relapsing EAE (CR-EAE). All Mice were examined daily for behavioral deficits and all euthanized and sacrificed on day 50. Preliminary result showed that TQ due to its antioxidant effect is almost 90% preventive and 50% curative in CR-EAE. This result could assist further studies on the mechanism of action of TQ in CR-EAE and explore the possibility of treating the human chronic relapsing multiple sclerosis phase.

12. Disclosure of medical errors: A view through a global lens

There are ongoing efforts worldwide to minimize the occurrence of medical errors. However, the issue of honest disclosure of a medical error to the patient or their family has been relatively unattended. We have previously reported the Canadian provincial initiatives encouraging open disclosure of a critical event and have suggested its integration into a ‘no-fault’ model. In the absence of uniform policies directing appropriate disclosure of a medical error, substantial scope exists for breaching the patient’s trust if errors during the process of care are not disclosed. We reviewed the various medical error disclosure initiatives across the globe to analyze the progress made in this key area. In 2001, the United States (US) Joint Commission on Accreditation of Healthcare Organizations (JCAHO) mandated an open disclosure of any critical event during care to the patient or their families. This was deemed as an essential accreditation standard for the institution. In Australia, the Australian Council for Safety and Quality in Health Care integrates the disclosure process with a risk management analysis towards investigating the critical event. In New Zealand, the patients suffering a medical error are rehabilitated and compensated through a no-fault, state-funded compensation scheme. The National Health Services (NHS) of the United Kingdom directs the doctors and managers to inform a patient of an act of negligence or omission that causes harm. The NHS scheme offers a remedial package to the patient including an apology and financial compensation in return for the patients waiving their right to litigate. The Canadian provincial initiatives, though similar in content, remain isolated because of their non-mandatory nature and absence of federal or provincial laws on disclosure. In Conclusion, we suggest that a uniform national policy centered on addressing errors in a non-punitive manner and respecting the patient’s right to an honest disclosure be implemented. Kalra J, Massey KL, Mulla A. Disclosure of medical error: policies and practice. Journal of the Royal Society of Medicine 2005; 98(7): 307-09. Hebert PC, Levin AV, Robertson G. Bioethics for clinicians: 23. Disclosure of medical error. CMAJ 2001; 164(4):509-13. Mazor KM, Simon SR, Gurwitz JH. Communicating with patients about medical errors: a review of the literature. Arch Intern Med. 2004; 164(15):1690-7.

19. Prevalence of diagnostic discordance: A retrospective analysis of autopsy findings and clinical diagnoses

The prevalence of medical error in health care systems has compromised the quality of health care delivery. The research on medical errors in hospitalized population has consistently revealed high rates of misdiagnosis. Autopsy examination has been an established tool for quality assurance programs. The objective of this study was to determine the discrepancy rates between clinical and autopsy findings in patients admitted to various hospitals (Royal University hospital, RUH; St. Paul’s hospital, SPH; Saskatoon city hospital, SCH) of Saskatoon Health Region. A retrospective record review of the medical and autopsy charts was carried out for all the deceased adult in-patients admitted during the years 2002, 2003, and 2004. All autopsies were carried out either in the morgue of RUH or at SPH hospital. A total of 3416 in-patient deaths were registered during the study period. Autopsies were performed on 206 of the deceased resulting in an autopsy rate of 6%. In accordance with selection criteria, 158 cases were included for this study. The mean age of subjects was 66.6 ± 15.2 years with a range of 16 – 94 years. The total concordance rate in this study between clinical and autopsy diagnoses was 75.3%. The discordance rate was 20.9% and in 3.8% of the study population a conclusive clinical or autopsy diagnoses was not finalized. The concordance and discordance rate between clinical diagnoses and autopsy findings when compared between the patients of two hospitals (RUH and SPH) were not significantly different. These results suggest that despite the technical advances in medical and diagnostic modalities, there still persists a significant discordance in clinical and autopsy diagnoses. Our study confirms the wide prevalence of diagnostic discrepancies in the health care system and emphasizes the value of autopsy as an effective quality improvement and educational tool with a strong impact on quality management. Roosen J, Frans E, Wilmer A, Knockaert DC, Bobbaers H. Comparison of premortem clinical diagnoses in critically ill patients and subsequent autopsy findings. Mayo Clin Proc 2000; 75:562-67. Sonderegger-Iseli K, Burger S, Muntwyler J, Salomon F. Diagnostic errors in three medical eras: a necropsy study. Lancet 2000; 10355:2027-31. Kalra J. Medical Error: An Introduction to Concepts. Clinical Biochemistry 2004;37:1043-51.

Congenital vesicovaginal fistula with transverse vaginal septum and ectopic ureter opening in proximal vagina: case report and brief review

Congenital vesicovaginal fistula is an extreme rarity. We report on a case of a 22-year-old lady who presented with menouria and infertility. On evaluation, she was found to have congenital vesicovaginal fistula, a nonfunctioning right kidney with ectopic ureter and transverse vaginal septum. Abdominal repair of the fistula, right nephroureterectomy, and excision of the vaginal septum was performed.

Intraarterial urokinase produces significant attenuation of infarction volume in an embolic focal ischemia model

A number of models of focal ischemia have been created to mimic acute middle cerebral artery (MCA) occlusion. In the present series of experiments, we report our observations on the thrombin model of MCA occlusion and the neuroprotective effects of intraarterial thrombolysis with two doses of urokinase (2500 and 5000 units/kg). In all experiments male Wistar rats were used and the animals were allowed to recover for 48 h before assessment of neurobehavioral performance on a four-point scale. The extent of cerebral hemispheric damage was calculated as the percentage of brain infarction using TTC staining. Occlusion of the MCA was effected by the introduction of an autologous blood clot into the internal carotid artery (ICA) approximately 2 mm from the origin of the MCA. This clot was formed by the drawing of 10 microl of blood into a bovine thrombin (20 microg per animal) containing intraarterial catheter, which was inserted into the right ECA. After standing for 15 min to allow clot formation, the catheter was advanced gently through the ICA to the site of injection. MCA occlusion produced a consistent large infarction in all animals. Urokinase infusion (i.a. ) was started 2 h after arterial occlusion in the initial series. In animals treated with low dose urokinase infusion there was mild protection. Animals treated with high dose urokinase infusion showed a highly significant improvement in the motor recovery and a decrease in the extent of infarction compared to control animals. In the final group, the infusion of urokinase was delayed for 3 h. While producing protection in some animals, it also produced intracerebral hemorrhage in two of eight animals. Thus delay of infusion to 180 min increased the risk of hemorrhage. This model may in the future be used to test the protective effects of combination therapy with thrombolysis and neuroprotective medications.

Increased oxidative stress in rat liver and pancreas during progression of streptozotocin-induced diabetes

1. Oxygen free radicals have been suggested to be a contributory factor in complications of diabetes mellitus. There are many reports indicating the changes in parameters of oxidative stress in diabetes mellitus. In this study we aimed to identify whether oxidative stress occurs in the liver and pancreas in the initial stages of development of diabetes. 2. We therefore investigated the lipid peroxide level (thiobarbituric acid-reactive substances, TBARS) and activities of antioxidant enzymes [superoxide dismutase (SOD), catalase and glutathione peroxidase] in liver and pancreas of control and streptozotocin-induced diabetic rats at various stages of development of diabetes. 3. Male Sprague-Dawley rats were divided into two groups: group I, control (n = 42) and group II, diabetic (n = 42). Each group was further subdivided into seven groups consisting of six rats each. Rats in these subgroups were studied at weekly intervals (0 to 6 weeks). Plasma glucose levels, TBARS levels and activities of antioxidant enzymes were measured in liver and pancreas at various time intervals. 4. There was a significant (P < 0.05) and progressive increase in TBARS levels of liver and pancreas in the diabetic group. Total SOD and Cu-Zn-SOD activity increased (P < 0.05) with progression of diabetes while Mn-SOD activity showed no significant change in either tissue. Catalase and glutathione peroxidase activities increased significantly (P < 0.05) in liver and pancreas. 5. Immunohistochemical study of pancreatic islet revealed a decrease in the expression of insulin with progression of diabetes. However, glucagon and somatostatin showed an increase in immunoreactivity and a difference in their distribution pattern. 6. The findings of the present study suggest that oxidative stress starts at early onset of diabetes mellitus and increases progressively. In conclusion, the structural damage to these tissues or complications of diabetes mellitus may be due to oxidative stress.

Cardiac depression and cellular injury in hemorrhagic shock and reinfusion: role of free radicals

We investigated the effect of hemorrhagic shock and reinfusion on the cardiac function and contractility, plasma CK and CK-MB activity and lactate concentration, oxyradical-producing activity of polymorphonuclear leukocytes (PMNL-CL), cardiac chemiluminescence (LV-CL), antioxidant enzyme activity [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX)] and malondialdehyde (MDA) concentration in anesthetized dogs to determine the role of oxyradicals in cardiac depression and cellular injury in hemorrhagic shock and reinfusion. The dogs were assigned into three groups: I (sham), 4 h duration; II (S + R), 2 h of shock followed by reinfusion for 2 h; III (SOD + S + R), as II but pretreated with PEG-SOD. Hemorrhagic shock was produced by withdrawal of blood to maintain the mean arterial pressure at 50 +/- 5 mm Hg. Cardiac function and contractility were depressed during hemorrhagic shock. Plasma CK, CK-MB and lactate increased during shock. Following reinfusion after 2 h of shock hemodynamic parameters and plasma lactate tended to return towards control values. Plasma CK and CK-MB, PMNL-CL and cardiac MDA, total-, Mn- and CuZn-SOD activity increased while LV-CL decreased. In spite of the increase in the antioxidant reserve, there was oxidative damage. Pretreatment with SOD attenuated the deleterious effects of shock and reinfusion on the cardiovascular function, plasma CK, and CK-MB, PMNL-CL, cardiac MDA, SOD, and LV-CL. Protection was incomplete for cardiovascular function and plasma CK and CK-MB. These results suggest that oxyradicals may partly be involved in the deterioration of cardiovascular function and cellular injury during hemorrhagic shock and reinfusion.

Prevention of Hypercholesterolemic Atherosclerosis by Garlic, an Antixoidant

BACKGROUND: Investigations of the effects of high cholesterol diet in the presence and absence of garlic on the genesis of atherosclerosis, the blood lipid profile, aortic tissue lipid peroxidation product malondialdehyde, chemiluminescence, a marker for antioxidant reserve and activity of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase were made in rabbits. METHODS AND RESULTS: Four groups of 10 rabbits each were studied: group 1 was given regular rabbit chow, group 2 was given rabbit chow diet supplemented with garlic powder (300 mg twice daily orally), group 3 was given 1% cholesterol diet, group 4 was given 1% cholesterol diet supplemented with garlic powder (300 mg twice daily orally). Blood concentration of triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol were measured before and after 4 and 10 weeks of experimental diets. The aorta was removed at the end of protocol (10 weeks) for assessment of atherosclerotic changes (gross and microscopic), malondialdehyde concentration, chemiluminescence, and activity of antioxidant enzymes. Total cholesterol, low density-lipoprotein cholesterol and ratio of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol and ratio of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol increaserd in group 3 and 4; the increase was smaller in group 4 than in in group 3 although not significant. Serum high-density lipoprotein cholesterol decreased to a similar extent in groups 3 and 4. Serum triglyceride and very low-density lipoprotein cholesterol remained unchanged in group 3 but increased in group 4. These values were significantly higher than those in group 1. Garlic in rabbits with control diet decreased the levels of triglyceride and very low density lipoprotein but did not affect the levels of total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol and the ratio of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol. There was an increase in aortic tissue malondialdehyde, chemiluminescence, and activities of catalase and glutathione peroxidase in group 3 compared with those in group 1. Levels of aortic malondialdehyde, chemiluminescence, catalase, and glutathione peroxidase were lower in group 4 compared with group 3; however, values for malondialdehyde and chemiluminescence were lower and that of catalase and glutathione peroxidase were higher in group 4 compared with group 1. Superoxide dismutase activity was similar in all the four groups. Malondialdehyde, chemiluminescence, and activity of catalase of aortic tissue decreased while activity of glutathione peroxidase increased in group 2. Atherosclerotic changes were lower in group 4 compared with group 3. Histologic changes were practically similar in groups 3 and 4. CONCLUSIONS: Increased levels of malondialdehyde, chemiluminescence, and antioxidant enzymes associated with development of atherosclerosis suggests a role for oxygen free radicals in the pathogenesis of hypercholesterolemic atherosclerosis. The protection afforded by garlic was associated with decrease in aortic malondialdehyde and chemiluminescence inspite of no change in serum cholesterol. These findings suggest that oxygen free radicals are involved in the genesis and maintenance of hypercholesterolemic atherosclerosis and that use of garlic can be useful in preventing the development of hypercholesterolemic atherosclerosis.

Antioxidant defense system in diabetic kidney: a time course study

Oxygen free radicals (OFRs) have been suggested to be a contributory factor in complications of diabetes mellitus. In the present study, we investigated the lipid peroxide level measured as thiobarbituric acid reactive substances (TBARS) and activities of antioxidant enzymes viz., [superoxide dismutase (SOD), catalase (CAT) and glutathione-peroxidase (GSH-Px)] in the kidney of streptozotocin induced diabetic rats at various stages of development of diabetes. Sprague Dawley rats were divided into two groups: group I, control (n = 42) and group II, diabetic (n = 42). Each group was further subdivided into seven groups each consisting of six rats. Rats in subgroups were studied at weekly intervals (0 to 6 weeks). Blood glucose levels were estimated at the time of sacrifice. TBARS levels and activity of antioxidant enzymes were measured in kidney. The levels of TBARS in the diabetic group increased initially, dropped to baseline level after 2 weeks and then progressively increased at 5th and 6th week (p < 0.05). There was an increase in catalase activity at first week after that it decreased as compared to control group. However, GSH-Px activity in the diabetic group increased after 1 week and then remained at the same level except a small drop in the 2nd week. Total SOD and CuZn-SOD activity increased significantly in diabetic kidney as compared to controls at all time intervals, while Mn-SOD activity showed no change. The present findings suggest that oxidative stress accompanies at early onset of diabetes mellitus and the susceptibility of the kidney to oxidative stress during the early stages may be an important factor in the development of diabetic nephropathy.

Time course study of oxidative stress in aorta and heart of diabetic rat

1. Oxygen free radicals have been suggested to be a contributory factor in complications of diabetes mellitus. In the present study, we investigated the lipid peroxide level [thiobarbituric acid-reactive substances (TBARS)] and activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) in aorta, heart and blood of control and streptozotocin-induced diabetic rats at various stages of development of diabetes (0 to 6 weeks). 2. There was no change in the TBARS levels of aorta, heart and blood in the control group. A significant (P < 0.05) increase in TBARS levels of aorta, heart and blood was observed in the diabetic group. 3. There were no significant changes in the activities of superoxide dismutase, catalase and glutathione peroxidase in the aorta, heart and blood of control rats at all time intervals. In the diabetic group, there was a significant (P < 0.05) increase in the activity of superoxide dismutase and glutathione peroxidase in aorta from the fourth week onwards while the activity of catalase increased at all time intervals. In the heart of diabetic rats, the activity of total superoxide dismutase and Cu-Zn-superoxide dismutase increased significantly (P < 0.05) from the second week onwards while activity of Mn-superoxide dismutase decreased at the fourth week and increased at the sixth week. The activity of catalase and glutathione peroxidase increased significantly (P < 0.05) at all time intervals. In the blood, the activity of superoxide dismutase and glutathione peroxidase increased from the third week while catalase activity increased from the fourth week. 4. The present findings suggest that oxidative stress starts at early onset of diabetes mellitus and increases progressively.

Glucose-induced decrease in glutamate levels in ischemic human brain by in-vivo microdialysis

Glutamate is one of the principal neurotoxins in the pathogenesis of ischemic neuronal injury. Elevated glutamate levels in ischemia have been well documented in many animal stroke models. Recent work in humans also shows a similar trend. We have used our acute focal ischemic model of the human brain to study the response of glutamate levels by in vivo microdialysis during ischemia using two different perfusates. The addition of 30 mM of glucose to the perfusate attenuated the percentages of dialysate glutamate levels from 4.27 +/- 1.7 to 1.34 +/- 0.47 (P < 0.001) during partial ischemia and from 21.42 +/- 6.05 to 7.25 +/- 1.43 (P < 0.05) with total ischemia. The pre-ischemic values of glutamate were similar with the two perfusates. These results indicate that the ischemia-induced rise in glutamate is attenuated by exogenous glucose delivery in the human stroke model.

Evaluation of monoaminergic neurotransmitters in the acute focal ischemic human brain model by intracerebral in vivo microdialysis

The release of neurotransmitters principally glutamate during cerebral ischemia has been extensively studied. It is well recognized that ischemia induced release of glutamate plays a key role in "excitotoxic" neuronal death. The role of monoaminergic neurotransmitters is however unclear. The purpose of this study was to evaluate the extracellular norepinephrine, 3,4-dihydroxyphenylacetic acid (DOPAC), 5-hydroxyindoleacetic acid (5-HIAA) and serotonin (5-HT) under varied degrees of ischemia in the acute focal ischemic model of the human brain by in-vivo microdialysis. The ischemic response of these amines was correlated with the glutamate levels. Our study concludes that these amines and metabolites can be detected in the human "stroke" model. No marked fluctuations were noted in the levels of norepinephrine and DOPAC. However, significant changes to partial and total ischemia were noted in the extracellular levels of 5-HIAA and 5-HT. These compounds showed a dramatic increase with the onset of ischemia with higher detectable levels in the partial ischemic state in comparison to the total ischemic dialysate levels. The exact role played by the differential increase in the levels of 5-HT to the other catecholamines in the pathogenesis of ischemic neuronal damage remains unclear and warrants further study.

Oxidative stress as a mechanism of cardiac failure in chronic volume overload in canine model

We investigated the effects of chronic volume overload in the absence or presence of vitamin E supplements on the cardiac function and contractility, cardiac malondialdehyde (MDA)--a lipid peroxidation product--cardiac antioxidant enzyme activity and antioxidant reserve in canine model. The dogs were divided into three groups of seven dogs each: group I, control; group II, mitral regurgitation (MR) of 4 months duration; and group III, MR of 4 months duration receiving vitamin E (40 U/kg/daily) orally. MR was created by detaching two or more chordae tendinae to raise left atrial pressure to 2.5 to three times normal. MR produced a decrease in the index of myocardial contractility with little change in myocardial function. Decrease in myocardial (left and right ventricles) contractility was associated with an increase in cardiac MDA, and a decrease in cardiac antioxidant reserve and antioxidant enzyme activity. Prevention of volume overload-induced decrease in myocardial contractility by vitamin E was associated with a decrease in cardiac MDA and an increase in cardiac antioxidant reserve and glutathione peroxidase activity towards control levels. Superoxide dismutase and catalase activity remained depressed in vitamin E-treated group. The results indicate that chronic volume overload decreases the contractility of both right and left ventricles and is associated with oxidative stress in both ventricles. These results support the hypothesis that oxygen free radicals are involved in the chronic volume overload-induced cardiac depression.

Effects of probucol on hypercholesterolemia-induced changes in antioxidant enzymes

Effects of high cholesterol diet (0.5% and 1%) on the activity of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px)] in the aortic tissue of rabbits were investigated in the absence or presence of probucol (0.5 gm/kg daily, orally). Five groups of ten rabbits each were studied. Group I, regular rabbit chow diet; Group II, chow + 0.5% cholesterol; Group III, chow + 0.5% cholesterol+probucol; Group IV, chow + 1% cholesterol and Group V, chow + 1% cholesterol+probucol. The aorta was removed at the end of 4 months for measurement of the antioxidant enzymes. An increase in activity of aortic antioxidant enzymes was noted in cholesterol-fed rabbits (Groups II and IV), being similar for SOD and catalase but higher for GSH-Px in Group IV as compared to Group II. Probucol was ineffective in altering this cholesterol-induced increase in enzyme activity except in Group III where it increased the activity of GSH-Px. These results suggest that aortic antioxidant enzymes are affected in hypercholesterolemia and that probucol is ineffective in altering the aortic antioxidant enzyme activity except GSH-Px activity which increased in 0.5% cholesterol-fed rabbits. The protective effects of probucol against hypercholesterolemic atherosclerosis may be partly due to an increase in the GSH-Px activity at low levels of hypercholesterolemia. At higher levels of hypercholesterolemia, the protective effects of probucol could be due to its antioxidant activity.

Lipid peroxidation and activity of antioxidant enzymes in diabetic rats

We hypothesized that oxygen free radicals (OFRs) may be involved in pathogenesis of diabetic complications. We therefore investigated the levels of lipid peroxidation by measuring thiobarbituric acid reactive substances (TBARS) and activity of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT)] in tissues and blood of streptozotocin (STZ)-induced diabetic rats. The animals were divided into two groups: control and diabetic. After 10 weeks (wks) of diabetes the animals were sacrificed and liver, heart, pancreas, kidney and blood were collected for measurement of various biochemical parameters. Diabetes was associated with a significant increase in TBARS in pancreas, heart and blood. The activity of CAT increased in liver, heart and blood but decreased in kidney. GSH-Px activity increased in pancreas and kidney while SOD activity increased in liver, heart and pancreas. Our findings suggest that oxidative stress occurs in diabetic state and that oxidative damage to tissues may be a contributory factor in complications associated with diabetes.

Paraneoplastic hypercalcemia associated with uterine papillary serous carcinoma

Hypercalcemia associated with endometrial carcinoma is rare. We report a patient with serous papillary endometrial carcinoma with paraneoplastic hypercalcemia due to parathyroid hormone-related peptide (PTHrP). To the best of our knowledge this is the first report of hypercalcemia due to PTHrP in this type of tumor.

GABA concentrations in the striatum following repetitive cerebral ischemia

GABAergic neurons in the striatum are very sensitive to the effects of ischemia. The progressive decline in striatal GABA following transient forebrain ischemia in gerbils may be secondary to either a decreased production or an increase in reuptake mechanisms or both. The current experiment was designed to evaluate release of GABA by stimulation with K+ or inhibition of its uptake with nipecotic acid or their combination (K+ nipecotic) after repetitive forebrain ischemia in gerbils by in-vivo microdialysis on Days 1, 3, 5, and 14 following the insult. Infusion of nipecotic acid or potassium chloride, resulted in a significant increase in extracellular GABA. This response was significantly decreased in the post-ischemic animals. The synergistic effect of increased GABA concentrations by the infusion of nipecotic acid + potassium chloride seem in the controls was not evident in the post-ischemic animals. In conclusion, though there is a reduction in the extracellular GABA concentrations in the first week following an ischemic insult, restorative mechanisms are operative in the second week as seen by the increasing GABA concentrations.

The differential effect of alloantigen-blocking antibodies on unprimed and memory T helper cells

Responsiveness to recall antigens by memory and naive T helper cells is different. To study whether such a difference is also applicable to affinity for allorecognition, we analyzed the effect of an IgG MLR blocking antibody separated from sera of patients with known kidney transplant chronic rejection on primed and unprimed CD4+ T cell alloreactivity. The results show that addition of the IgG fraction inhibits the patient's own unprimed T helper cell responses to a panel of four different alloantigens as well as a third-party mixed lymphocyte response. The same IgG fraction inhibited third-party naive T helper cell, but not autologous unprimed T helper cell, proliferation to adherent anti-CD3 antibody, which suggests that the mechanism of inhibitory action of the IgG is allogeneic-dependent. This IgG also did not induce inhibition of any of the T helper cell clone responsiveness, raised from the same or other patients, when stimulated with the same alloantigens used for unprimed cell alloactivation. Differential responses of naive and memory CD4+ T cells to alloantigens may explain some differences between the in vivo and in vitro systems and why allograft rejection can proceed in the presence of allogeneic blocking antibodies.

Amonafide: An active agent in the treatment of previously untreated advanced breast cancer--a cancer and leukemia group B study (CALGB 8642)

Amonafide is a new imide derivative of naphthalic acid. The drug had demonstrated significant activity in preclinical studies and some activity in Phase I trials. The drug is extensively metabolized and detected in plasma and urine. Its toxicity has previously been correlated to the formation of an active metabolite, N-acetyl-amonafide. Amonafide was chosen for inclusion in the Cancer and Leukemia Group B (CALGB) master metastatic breast cancer protocol. CALGB 8642 randomizes previously untreated metastatic breast cancer patients either to one of several Phase II agents given for up to four cycles and then followed by standard cyclophosphamide-doxorubicin-5-fluorouracil, or to immediate treatment with standard cyclophosphamide-doxorubicin-5-fluorouracil. The end point of CALGB 8642 is to assess the difference in survival, toxicity, and overall response when limited exposure to Phase II agents precedes standard chemotherapy. This report deals only with amonafide as a Phase II agent. Comparisons with the cyclophosphamide-doxorubicin-5-fluorouracil arm will not be addressed. Patients had to have histologically documented measurable breast cancer and a performance status of 0-1. Patients could not have had prior chemotherapy for metastatic disease. Prior adjuvant chemotherapy was permitted. Patients could not have visceral crisis. Amonafide was given at 300 mg/m2/day i.v. for 5 days, and repeated at 21-day intervals for a maximum of four cycles. Escalation and reduction in dose was mandated dependent on hematotoxicity or lack thereof. Toxicity was primarily hematological and bimodal: 32% had grade 3 or 4 leukopenia and 24% had grade 3 or 4 thrombocytopenia; 22% had no leukopenia and 44% had no thrombocytopenia. The response rate was 18%, including one complete response. When response was analyzed by hematological toxicity, there was a 35.7% response if patients had leukopenia grade 3/4 (versus 8.3%, P = 0.08). There was a 50% response if patients had thrombocytopenia grade 3/4 (versus 7.1%, P = <0.01). We conclude that amonafide is somewhat active in previously untreated breast cancer patients. There may be a steep dose-response curve, based on the significant correlation between myelosuppression and response. Rates of responses in patients adequately dosed (i.e., with significant hematotoxicity) with amonafide ranged from 35 to 50%. Further studies will incorporate individualized dosing based on pretreatment acetylator phenotyping.