Protective effect of Withaferin-A on tumour formation in 7,12-dimethylbenz[a]anthracene induced oral carcinogenesis in hamsters

With an aim to investigate the protective effect of Withaferin-A on 7,12-dimethylbenz[a]anthracene (DMBA) induced oral carcinogenesis in Syrian golden hamsters, tumour incidence, tumour volume and tumour burden and status of detoxication agents, lipid peroxidation and antioxidants in DMBA administered (3 times/week for 14 weeks) hamsters were assessed. Hundred percent tumour formation in DMBA alone administered animal was observed. Oral administration of Withaferin-A (20 mg/kg body weight) to DMBA administered animals for 14 weeks completely prevented the tumour incidence, tumour volume and tumour burden. Also, Withaferin-A showed significant anti-lipid peroxidative and antioxidant properties and maintained the status of phase-I and phase-II detoxication agents during DMBA-induced oral carcinogenesis. The results thus indicate that the protective effect of Withaferin-A is probably due to its anti-lipid peroxidative and antioxidant functions as well as modulating effect on carcinogen detoxication during DMBA-induced oral carcinogenesis.

Transobturator mesh for cystocele repair: a short- to medium-term follow-up using 3D/4D ultrasound

OBJECTIVE

Anterior colporrhaphy has been shown to have limited medium-term success rates in cystocele repair. Many clinicians use mesh implants, but their safety and efficacy are controversial. We therefore performed an external surgical audit using three- and four-dimensional pelvic floor ultrasound to study the short- to medium-term results of transobturator mesh placement.

METHODS

Forty-six women who had undergone transobturator mesh anterior repair using the Perigee(TM) system were invited back for a follow-up appointment conducted by two non-surgeons. The appointment consisted of a standardized interview, clinical examination using the International Continence Society Pelvic Organ Prolapse Quantification system (ICS POP-Q) and translabial ultrasound examination.

RESULTS

The mean follow-up time was 10 (range, 2-24) months. There had been no major intra- or postoperative complications. Thirty-six (78%) patients were subjectively satisfied with the outcome of the procedure. Cystocele recurrence (Stage 2 or 3) was observed in six (13%) patients. There were three (6.5%) cases of mesh erosion. On translabial ultrasound, we observed cystocele recurrence dorsal to the mesh in five women, associated with a marked change in mesh axis on Valsalva, implying dislodgment of the superior anchoring arms. The mesh was measured at a mean of 21 (range, 8.8-37.3; SD, 7.0) mm in length.

CONCLUSIONS

At 10-month follow-up the Perigee procedure seems to be safe and effective for cystocele repair, with a satisfaction rate of 78%. In some women recurrence may occur due to dislodgment of the superior anchoring arms.

Consolidated five-year experience with laparoscopic inguinal hernia repair

INTRODUCTION

After the introduction of laparoscopic hernia repair to the National Health Service (NHS), we studied the benefits and practicality of carrying out this specialised hernia repair technique in a District General NHS hospital.

METHODS

Patients with groin hernia were stratified into groups for day-surgery or inpatient care based on Trust guidelines. Patients underwent laparoscopic trans-abdominal pre-peritoneal (TAPP) inguinal hernia repair by a single consultant surgeon. Patients were followed-up in the clinic. All data were collected prospectively on a structured proforma. Postal questionnaire was sent to 100 randomly selected patients who had surgery more than two years ago and responses were evaluated.

RESULTS

A total of 830 hernias were operated upon in 572 patients, aged between 16 and 89 years. Three hundred and twelve patients had the operation as a day-case procedure, and the remaining 260 were treated as inpatients. Incidental hernias were discovered in 19.1% of patients, and were treated simultaneously.

CONCLUSION

The laparoscopic tension-free TAPP method of hernia repair, as done here, is cost-effective and efficacious. Most patients can be treated as day-cases. A low recurrence rate (0.36%) with low morbidity makes it an attractive method for routine treatment of groin hernias in the NHS.

Force-frequency relation in frog-ventricle is dependent on the direction of sodium/calcium exchange in diastole

AIM

Force of contraction increases with stimulus-frequency in mammalian and amphibian hearts under control conditions. Here, we have analysed the mechanism of the force-frequency relation (FFR) in frog-ventricle.

METHODS

Circular strips of frog-ventricle were subjected to field-stimulation with frequencies in the range 0.03-0.2 Hz and force recorded on a chart-recorder. In another protocol, varying rest-periods were imposed while the preparation beat steadily at 0.2 Hz and the effect of rest on post-rest beat amplitude was noted.

RESULTS

Under control conditions, a positive FFR and a rest-induced decay of contraction amplitude (RID) were seen in the frequency range 0.03-0.2 Hz. With cadmium, nifedipine, nickel (40 micromol L(-1)), ryanodine and adrenaline (all drugs at 10 micromol L(-1) concentration, except nickel), the positive FFR and RID seen under control conditions persisted. When the bathing solution contained ouabain (10 micromol L(-1)) or low external sodium (40 mmol L(-1)), or high external calcium (5 mmol L(-1)), the FFR turned negative in the frequency range stated above and there were rest-induced potentiations (RIP).

CONCLUSION

When the conditions favour a net leak of calcium in diastole from intracellular stores via the calcium-extrusive mode of sodium-calcium exchanger (NCX), FFR is positive. An increase in frequency lessens the diastolic interval and therefore the diastolic calcium leak, thereby augmenting force. On the other hand, interventions which favour the calcium-acquisitive mode of NCX during diastole, changed the pattern of RID to RIP and converted FFR from positive to negative. With net diastolic calcium uptake, there is better store-filling and therefore higher force at lower frequencies.

Micronuclei and cell proliferation as early biological markers of ortho-phenylphenol-induced changes in the bladder of male F344 rats

ortho-Phenylphenol (OPP) and its sodium salt, sodium ortho-phenylphenate (SOPP), are widely used fungicides and antibacterial agents known to cause tumors in the bladders of male F344 rats. Previous studies in our laboratory have shown that micronuclei and cell proliferation were induced in the bladders of treated rats by a high dose of OPP. In our present studies, we investigated the relationship in dose response between these two biomarkers and previously reported tumor formation in the bladders of male F344 rats. Significant non-linear increases in micronuclei (MN) and BrdU-labeling were seen in the bladder cells of rats treated with the 8000 and 12,500 ppm doses of OPP and at 20,000 ppm SOPP. CREST anti-kinetochore staining showed that the micronuclei originated from both chromosomal loss and breakage. In addition, increases in MN were detected in the bladder but not in the bone marrow, underscoring the value of assessing genotoxicity in the target organ. In summary, these studies clearly show that at high doses, OPP and SOPP are genotoxic to the rat bladder. These results also indicate that micronucleus formation and cell proliferation can detect early OPP-induced changes in the rat bladder and may be useful as biomarkers for bladder carcinogens.

Ischemic Steal Syndrome: A Case Series and Review of Current Management

BACKGROUND

Currently over 5000 patients are receiving hemodialysis in Australia, which is an increase by approximately 7% each year. Distal ischemia secondary to the steal syndrome (ISS) is an uncommon but recognized complication. Several methods are now available to manage this problem including ligation, banding, and distal revascularization with interval ligation (DRIL). The aim of this report is to review the experience of the authors on this complication and its management at Royal Perth Hospital.

METHODS

The Vascular Physiology Laboratory Database was used to identify those patients referred for investigation of ISS. Data were collected retrospectively from these patients' files concerning their demographics, graft particulars, and type of interventional procedure. Patients were then recalled to assess long-term patency and current venous access and for postoperative vascular studies.

RESULTS

Eighteen people were identified with ischemic symptoms. The mean age was 66 (range, 44 to 82). Fourteen (77.8%) were men, and 15 (83.3%) were diabetic. Renal failure was secondary to diabetes in 8 patients, hypertension in 3, and a combination of both in 7 patients. Intervention was via the DRIL procedure in 12, ligation in 5, and banding in 1. One patient underwent angioplasty of the ulnar artery before DRIL. At follow-up (between 1 and 12 months), all DRIL bypass were patents. The 5 ligated patients all improved, and the patient who underwent banding thrombosed their graft.

CONCLUSION

The DRIL procedure should be considered the standard operation to manage ISS in that it manages the ischemia while maintaining the functional fistula. It is, however, still necessary to ligate some fistulae and seek alternative access. There are still no preoperative indicators as to who will suffer ISS.

Evaluation of hyperdiploidy in the bladder epithelial cells of male F344 rats treated with ortho-phenylphenol

Ortho-phenylphenol (OPP) is a broad-spectrum fungicide and anti-bacterial agent that has been shown to cause bladder cancer in male F344 rats. An earlier study to investigate the potential role of aneuploidy in OPP-induced bladder carcinogenicity, failed to detect increases in frequencies of hyperdiploidy/polyploidy in treated animals, presumably due to the presence of polyploid cells in the bladder. To overcome this problem, we utilized a novel approach to determine increases in numerical alterations in the slowly dividing replicating cells of the rat bladder following treatment with OPP. Collagenase digestion of the bladder was used to enrich for actively-dividing cells and FISH in conjunction with BrdU was employed to detect hyperdiploidy in the replicating interphase cells. Initial studies were performed using FISH with a chromosome 4 probe. Follow-up studies were conducted with OPP and a positive control, vinblastine sulfate using probes for chromosomes 4 and 19. No significant increases in hyperdiploidy/polyploidy were seen in the replicating bladder cells of the OPP-treated rats using FISH with either the chromosome 4 or 19 probes. As expected, no significant increases in hyperdiploidy were seen in the non-replicating cells. In contrast, highly significant increases in hyperdiploidy/polyploidy, as detected using FISH with probes for either chromosome 4 or 19, were seen in the replicating cells from rats treated with a combination of OPP and vinblastine. The inability to detect increases in hyperdiploidy/polyploidy in the bladder of OPP-treated rats indicates that chromosome gain is unlikely to play a major role in the early genotoxic effects of OPP. However, the increase in hyperdiploidy/polyploidy induced by vinblastine sulfate in OPP-treated rats, clearly demonstrates that this approach using FISH in combination with BrdU is capable of detecting changes in chromosome number even in slowly-dividing tissues, such as the urinary bladder.

Enhancing the in vitro and in vivo detection of aneuploidy by fluorescence in situ hybridization with the use of bromodeoxyuridine as a proliferation marker

Aneuploidy is associated with spontaneous abortions, birth defects, and many types of human cancers. Currently there are few assays developed for the efficient detection of aneuploidy in vivo. However, with the recent availability of chromosome-specific DNA probes for the rat, fluorescence in situ hybridization (FISH) techniques could be used for the rapid and sensitive detection of aneuploidy in different tissue and cell types. In order to develop a system that can detect alterations in chromosome number in rat cells in vitro, we treated cultured rat lymphocytes with three aneugens-noscapine hydrochloride (0-150 microM) and vincristine and vinblastine sulfate (0-0.06 microM). 5-Bromo-2-deoxyuridine (BrdU; 1 microM) was added to the culture medium to allow proliferating and non-proliferating cells to be distinguished. To test this assay under in vivo conditions, 21-day-old male Sprague-Dawley rats were subcutaneously implanted with osmotic pumps that delivered BrdU (approximately 12 mg/kg per day) continuously. These rats were administered vinblastine sulfate (0, 0.5 and 1mg/kg) by intraperitoneal injection. The rat lymphocytes and hepatocytes incorporating BrdU were detected by immuno-fluorescent labeling, and FISH with a rat chromosome 4 probe was performed on the labeled and unlabeled cells. Highly significant increases in hyperdiploidy were seen in the replicating rat lymphocytes treated with noscapine, vincristine or vinblastine in vitro and in the rat hepatocytes treated with vinblastine in vivo. In contrast, no significant increase in hyperdiploidy was observed in the non-replicating cells. These results demonstrate that this BrdU-enhanced FISH assay with chromosome-specific rat probes can be used to efficiently detect numerical chromosomal aberrations in vitro and in vivo in slowly or moderately replicating rat tissues. The combination of BrdU-labeling and FISH allows the scoring of hyperdiploidy to be focused on the actively replicating cells, thereby increasing the sensitivity of the FISH technique.

Detection of micronuclei, cell proliferation and hyperdiploidy in bladder epithelial cells of rats treated with o-phenylphenol

o-Phenylphenol (OPP), a widely used fungicide and antibacterial agent, has been considered to be among the top 10 home and garden pesticides used in the USA. Earlier studies have consistently shown that the sodium salt of OPP (SOPP) causes bladder cancer in male Fischer 344 (F344) rats, whereas OPP has produced variable results. This difference has been attributed to the presence of the sodium salt. To determine cellular and genetic alterations in the rat bladder and the influence of the sodium salt, F344 rats were administered 2% OPP, 2% NaCl and 2% NaCl + 2% OPP in their diet for 14 days. Twenty-four hours before being killed the animals were administered 5-bromo-2'-deoxyuridine (BrdU) by i.p. injection. Bladder cells were isolated, stained with DAPI and scored for the presence of micronuclei and incorporation of BrdU into replicating cells. To determine changes in chromosome number, we used fluorescence in situ hybridization (FISH) with a DNA probe for rat chromosome 4. Significant increases in the frequency of micronuclei and BrdU incorporation were seen in bladder cells of rats from all treatment groups. In contrast, the frequency of hyperdiploidy/polyploidy in treated animals was not increased over that seen in controls. A high control frequency of cells with three or more hybridization signals was seen, probably due to the presence of polyploid cells in the bladder. The presence of polyploid cells combined with cytotoxicity and compensatory cell proliferation makes it difficult to determine whether OPP is capable of inducing aneuploidy in the rat urothelium. In summary, these studies show that OPP can cause cellular and chromosomal alterations in rat bladder cells in the absence of the sodium salt. These results also indicate that at high concentrations the sodium salt can enhance chromosomal damage in the rat urothelium.

Detection of micronuclei, cell proliferation and hyperdiploidy in bladder epithelial cells of rats treated with o-phenylphenol

o-Phenylphenol (OPP), a widely used fungicide and antibacterial agent, has been considered to be among the top 10 home and garden pesticides used in the USA. Earlier studies have consistently shown that the sodium salt of OPP (SOPP) causes bladder cancer in male Fischer 344 (F344) rats, whereas OPP has produced variable results. This difference has been attributed to the presence of the sodium salt. To determine cellular and genetic alterations in the rat bladder and the influence of the sodium salt, F344 rats were administered 2% OPP, 2% NaCl and 2% NaCl + 2% OPP in their diet for 14 days. Twenty-four hours before being killed the animals were administered 5-bromo-2'-deoxyuridine (BrdU) by i.p. injection. Bladder cells were isolated, stained with DAPI and scored for the presence of micronuclei and incorporation of BrdU into replicating cells. To determine changes in chromosome number, we used fluorescence in situ hybridization (FISH) with a DNA probe for rat chromosome 4. Significant increases in the frequency of micronuclei and BrdU incorporation were seen in bladder cells of rats from all treatment groups. In contrast, the frequency of hyperdiploidy/polyploidy in treated animals was not increased over that seen in controls. A high control frequency of cells with three or more hybridization signals was seen, probably due to the presence of polyploid cells in the bladder. The presence of polyploid cells combined with cytotoxicity and compensatory cell proliferation makes it difficult to determine whether OPP is capable of inducing aneuploidy in the rat urothelium. In summary, these studies show that OPP can cause cellular and chromosomal alterations in rat bladder cells in the absence of the sodium salt. These results also indicate that at high concentrations the sodium salt can enhance chromosomal damage in the rat urothelium.

Role of nitric oxide in experimental models of psychosis in rats

The aim of our study was to investigate the effects of the NO precursor L-arginine and the nitric oxide synthase inhibitor N omega-nitro-L-arginine (L-NORAG) on amphetamine-induced stereotypy, haloperidol-induced catalepsy and conditioned avoidance response (CAR) in rats. Amphetamine (3 mg/kg i.p.) was used for the induction of stereotypy, while for the induction of catalepsy and CAR, haloperidol (2 mg/kg i.p.) was used. This study was divided into 2 parts--acute administration of L-arginine (150 mg/kg i.p.) and L-NOARG (50 mg/kg i.p.) and chronic administration of L-arginine (150 mg/kg/day i.p.) and L-NOARG (50 mg/kglday i.p.) for 5 days. We found that L-arginine inhibited amphetamine-induced stereotypy and haloperidol-induced catalepsy, but intensified CAR. On the other hand, L-NOARG intensified stereotypy and catalepsy but inhibited CAR. Also, there was no significant difference between the scores of acute and chronic administration of L-arginine and L-NOARG. It is concluded from our study that nitric oxide produces conflicting results on various models of psychosis. L-arginine might be useful as an antipsychotic without causing extrapyramidal symptoms.

Idiopathic hypothalamic dysfunction with precocious puberty and adipsic hypernatremia first presenting in adolescence

BACKGROUND

Idiopathic hypothalamic dysfunction is a rare syndrome that has been described in young children. This syndrome is characterized by a disturbance of thirst regulation with hypernatremia, hyperosmolarity, and altered hypothalamic function.

PATIENT REPORT

At age 6 years the reported patients presented with precocious puberty, by age 12 years she had hypernatremia presumed secondary to central diabetes insipidus and was treated with DDAVP, and at age 14 was identified to have hyperprolactinemia. At age 19 she presented with serum sodium of 185 mg/dl during an episode of illness associated with dehydration. After hydration, her sodium remained elevated. Arginine vasopressin was measurable but inappropriate to serum sodium, while urinary cyclic AMP response to vasopressin was appropriate.

CONCLUSIONS

This is the first case of precocious puberty identified in association with the more classic features of idiopathic hypothalamic dysfunction, including later-onset hypernatremia, poor thermoregulatory function, obesity, and hyperprolactinemia.