P2X receptor-mediated visceral hyperalgesia in a rat model of chronic visceral hypersensitivity

BACKGROUND

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterised by abdominal pain and bloating in association with altered bowel movements. Its pathogenesis and the underlying molecular mechanisms of visceral hyperalgesia remain elusive. Recent studies of somatic and other visceral pain models suggest a role for purinergic signalling mediated by the P2X receptor (P2XR) family.

AIMS

To examine the role of P2XR signalling in the pathogenesis in a rat model of IBS-like visceral hyperalgesia.

METHODS

Visceral hypersensitivity was induced by colonic injection of 0.5% acetic acid (AA) in 10-day-old rats and experiments were conducted at 8 weeks of age. Dorsal root ganglion (DRG) neurons innervating the colon were labelled by injection of DiI (1,1'-dioleyl-3,3,3',3-tetramethylindocarbocyanine methanesulfonate) fluorescence into the colon wall.

RESULTS

Visceral hypersensitivity was reversed by TNP-ATP (2'-(or-3')-O-(trinitrophenyl) ATP), a potent P2X1, P2X3 and P2X2/3 receptor antagonist. Rapid application of ATP (20 microM) induced a fast inactivating current in colon-specific DRG neurons from both control and AA-treated rats. There was a twofold increase in the peak ATP responses in neurons from AA-treated rats. These currents were sensitive to TNP-ATP (100 nM). Under current-clamped conditions, ATP evoked a larger membrane depolarisation in neurons from neonatal AA-treated rats than in controls. P2X3R protein expression was significantly enhanced in colon-specific DRGs 8 weeks after neonatal AA treatment.

CONCLUSIONS

These data suggest that the large enhancement of P2XR expression and function may contribute to the maintenance of visceral hypersensitivity, thus identifying a specific neurobiological target for the treatment of chronic visceral hyperalgesia.

Postoperative flare-up of genital tuberculosis: a clinical reality

We report three cases of flare-up of tuberculosis (TB) following genital surgery. In two cases, both patients developed abdominal distension postoperatively with vomiting and fever following total laparoscopic hysterectomy. Polymerase chain reaction (PCR) analysis of fluid detected and aspirated from the abdomen under ultrasound guidance was positive for Mycobacterium tuberculosis. In another instance, the patient developed abdominal distension with discharge per vaginum following a vaginal hysterectomy. X-ray of the abdomen showed dilated bowel loops and also a pseudo acetabular right hip joint suggestive of TB. PCR analysis of ascitic fluid was positive for TB. All patients responded to anti-tuberculosis treatment.

Intraoperative magnetic resonance imaging in neurosurgery: the Brigham concept

The resection of brain tumors is limited by the surgeon's ability to precisely define margins. To overcome this problem, various neuronavigational tools have been used. The development of image-guided navigation systems represents a substantial improvement in the microsurgical treatment of various intracranial lesions. However, a major drawback of this technology is that they use images acquired preoperatively, on which the surgical planning and intraoperative performance is based. As the intracranial anatomy dynamically changes during a neurosurgical procedure, only intraoperatively acquired images can provide the neurosurgeon with the information needed to perform real-time, image-guided surgery. Because magnetic resonance imaging best delineates the soft-tissue extent of most tumors, it currently remains the superior method for intraoperative image guidance. In this review, we outline the development as well as current and possible future applications of the intraoperative MRI (iMRI) unit at the Brigham and Women's Hospital, Boston, MA.

Immunomodulation against leukemias and lymphomas: a realistic future treatment?

Immunotherapy offers the potential for cure of malignancy without the side effects too commonly seen with conventional chemotherapy. The efficacy of allogenic transplantation and monoclonal antibodies in hematological malignancies illustrate this principle and are now part of routine care. Newer cell based and molecular approaches aimed at stimulating cytotoxic activity against host derived tumor associated antigens are able to 'boost' anti-tumor immunity as judged by immunological assays in vitro. Although clinically meaningful responses were originally less evident, more promising results are now being reported. Our growing understanding of tumor immunology provide rationales for further improvements in the field.

Ulcerative keratitis associated with contact lens wear

To review the microbiological profile of ulcerative keratitis associated with contact lens (CL)-wear, 35 patients with culture-proven CL-associated microbial keratitis were studied between September 1999 and September 2002. Corneal scrapes and CL-care products were collected and were subjected to microbiological evaluation. Gram-negative bacilli alone were recovered from the corneal scrapes of all 35 (100%) patients, all 70 (100%) CL storage case wells and also from CL-care solution of six (17.14%) of the 35 patients. There was a significantly higher number of Pseudomonas aeruginosa (71.43%) isolated from eyes with CL-related keratitis than other bacterial isolates (28.57%) (P<0.001). Microbial contamination of CL storage cases was a great risk for gram-negative bacterial infection among soft CL-wearers.

Comparative bacteriology of acute and chronic dacryocystitis

AIMS

To compare the bacterial aetiology and their in vitroantibacterial susceptibilities of acute and chronic dacryocystitis.

METHODS

A retrospective analysis of patients with clinically diagnosed acute and chronic dacryocystitis who underwent microbiological evaluation presenting between January 2000 and December 2005 was carried out. Mucopurulent discharge through punctum, pus from burst abscess, incision drainage, and lacrimal sac content were taken and subjected to microbiological evaluation.

RESULTS

A total of 1891 patients of dacryocystitis were evaluated and subjected to microbiological evaluation, of which 566 (29.9%) had acute dacryocystitis and 1325 (70.1%) had chronic dacryocystitis. Of 1891 eyes, 1518 (80.3%) had pure bacterial growth and the remaining 373 (19.7%) had no growth. The percentage of culture-positivity was found to be higher in chronic dacryocystitis (90%) than in acute dacryocystitis (57.4%) (P<0.0001). A total of 1612 bacterial isolates were recovered from 325 acute and 1193 chronic dacryocystitis; in 1424 (93.8%) eyes, single bacterial species was isolated, and in the remaining 94 (6.2%) eyes, two bacterial species were isolated. The predominant bacterial pathogen isolated from acute dacryocystitis was Staphylococcus aureus(22.3%) followed by Pseudomonas aeruginosa(21.1%) and from chronic dacryocystitis was coagulase-negative staphylococci (CoNS) (44.2%), S. aureus(10.8%), and Streptococcus pneumoniae(10%). The highest percentage of bacterial isolates were susceptible to gatifloxacin (96.5%), ofloxacin (94.8%), and amikacin (91.1%). The percentage of resistance of bacterial isolates recovered from chronic dacryocystitis to gentamicin (45.7%), tobramycin (50.8%), norfloxacin (50.7%), and ciprofloxacin (30.4%) were found to be higher than that of bacterial isolates from acute infection to gentamicin (24.6%), tobramycin (35%), norfloxacin (36.5%), and ciprofloxacin (19.9%).

CONCLUSION

The proportions of S. aureusand Pseudomonasspp are higher in causing acute dacryocystitis, while the proportion of CoNS is higher in chronic dacryocystitis. The percentages of antibacterial resistant isolates were higher among bacterial species from chronic dacryocystitis.

Uterine artery embolization for symptomatic fibroids with imaging follow up

The aim of this study was to determine the effectiveness of uterine artery embolization (UAE) as a primary treatment method in treatment of symptomatic fibroids, whether there are any preembolization MRI characteristics of fibroid predictive of reduction in volume and assess reduction in uterine and dominant fibroid volumes using ultrasound (US) and MRI. Study was carried out in total of 32 patients aged 25-49 years (mean 40.9 years). Uterine and dominant fibroid volume were determined using US and MRI before UAE, MRI and US at 3 months and US alone at 6 and 12 months post-UAE, supplemented by clinical evaluation at interval of 3, 6 and 12 months. Procedure was carried out through unilateral femoral puncture using poly vinyl alcohol (PVA) particles 355-500 microm in size. All 32 patients had successful procedures. Overall, 25 patients responded, giving a clinical success rate of 78.12%. Mean reduction in volume of uterus and fibroid was 33 and 59.7% and 48.9 and 75.5% on US at 3 and 12 months respectively, and 33.3 and 58.6% on MRI at 3 months. Volume reduction on US and MRI at 3 months was highly correlative. There was no statistical difference in size reduction in volume of fibroids, which were hypointense or hyperintense on T2-weighted image (T2WI) on pre-UAE MRI. Uterine artery embolization leads to good technical success and fibroid volume reduction. Ultrasound alone may be used for follow up of patients post-UAE. Preprocedure signal characteristics on T2WI are not predictors of volume reduction after UAE.

Transcriptional upregulation of human cathepsin L by VEGF in glioblastoma cells

The role of vascular endothelial growth factor (VEGF) on cathepsin L expression was investigated in human glioblastoma cells (U87MG). Our results demonstrate the transcriptional upregulation of cathepsin L expression by VEGF. Transient transfection of U87MG cells with VEGF expression vector significantly increased cathepsin L activity. These results were further corroborated by a parallel increase in the mRNA levels and promoter activity of cathepsin L by VEGF. By deletion analysis, we identified a 47 base pair VEGF response element (VRE) in human cathepsin L promoter. Site directed mutagenesis studies demonstrated that both SP-1 and AP-4 motifs present in this region contribute to VEGF responsiveness. These results prove for the first time that over-expression of VEGF in human glioblastoma cells induces cathepsin L expression at the transcriptional level. This mechanism could be involved in the enhanced tumorogenic potential of these cells.

Genital tuberculosis in Indian infertility patients

OBJECTIVES

To analyze the clinical and laparoscopic features of 40 infertile women with genital tuberculosis.

MATERIALS AND METHODS

This prospective clinical study was carried out at a tertiary care hospital from October 1, 2004, to August 30, 2006, with 150 infertile women in whom there was clinical suspicion of genital tuberculosis. All underwent diagnostic laparoscopy and biopsy for confirmation and other causes of infertility were excluded.

RESULTS

Among the 40 infertile women affected with genital tuberculosis there were cases of primary (n=30) and secondary (n=10) infertility; pelvic pain (n=8); menorrhagia (n=9); oligomenorrhea (n=7); hypomenorrhea (n=8); and primary (n=2) and secondary (n=2) amenorrhea. There were histories of pulmonary (n=9) and abdominal tuberculosis (n=6), ectopic pregnancy (n=4), and antitubercular treatment (n=10) in 10. There were cases of positive Mantoux test results (n=2); endometrial aspiration showing tubercular endometritis (n=10); positive acid-fast bacillus culture results (n=1); and positive polymerase chain reaction results (n=9). Laparoscopic examination revealed abnormally dilated, tortuous, and blocked fallopian tubes (n=13); peritubal and periovarian adhesions (n=18); Fitz Hugh Curtis syndrome (n=15); omental adhesions (n=18); and bowel adhesions (n=15). Hysteroscopy revealed flimsy intrauterine adhesions (n=7). All patients were treated for tuberculosis and 13 were counseled for in-vitro fertilization and embryo transfer or adoption.

CONCLUSION

Genital tuberculosis is common in India and a combination of clinical and laparoscopic diagnoses, along with endometrial histopathologic studies, acid-fast bacillus culture, and polymerase chain reaction assays provides the best available method for the diagnosis of genital tuberculosis in infertile women.

Primitive neuroectodermal tumor of the uterus: a case report

Peripheral primitive neuroectodermal tumor is a rare group of tumors belonging to the Ewing's family of tumors. The female genital tract is a rare site of origin and to date there are 14 reported cases in the literature. We hereby report the 15th case of uterine primitive neuroectodermal tumor in a 24-year-old multipara in the reproductive age group. A 24-year-old multipara presented with pain and mass abdomen. Physical examination revealed a pelvic mass enlarged to 20 weeks size gravid uterus, fixed, tender and hard, occupying the whole pelvis. Magnetic resonance imaging showed a large mass posterior to the uterus. She underwent panhysterectomy and debulking of the tumor. Histopathology confirmed the diagnosis. She developed recurrence of the tumor within a month and is now on chemotherapy.

Fine needle aspiration cytology in reactional and non-reactional leprosy

BACKGROUND

Histopathological evaluation of skin lesions is not feasible in many leprosy endemic areas. Fine needle aspiration cytology (FNAC) is a simpler tool compared to histopathology for the evaluation of the cytomorphology of skin lesions.

AIMS

To study the cytomorphology of leprosy lesions in fine needle aspirates and correlate it with the histopathology.

METHODS

Seventy leprosy patients diagnosed and classified according to Ridley Jopling scale were included. Fine needle aspirates were taken from the lesion followed by a skin biopsy from the same site for histopathological examination after H/E staining.

RESULTS

Borderline leprosy patients with Type I reaction showed significantly large numbers of giant cells, collagen and elastin in their smears as compared to those without reaction. The smears were more heavily cellular with fragmented collagen and elastin along with significant increase in neutrophils in patients with Type II reaction while foamy macrophages with fatty background were common in non-reactional lepromatous leprosy patients. A complete correlation between histopathological and cytomorphological findings was observed in 77.3% of cases.

CONCLUSION

FNAC may be used as an alternative tool to assess leprosy lesions in areas where histopathological services are not readily available.