Primary intraventricular haemorrhage: a rare presenting feature of arteriovenous malformation in children

Two cases of arteriovenous malformation (AVM) of the brain presented with primary intraventricular haemorrhage in eleven and thirteen years old children, respectively. The cases responded favourably to therapy with steroids, anti-epileptic drugs and therapeutic embolisation in the former. Though such presentation accounts for 3% of the adult intracranial bleeds secondary to AVM rupture, the same has not been reported in children.

Mining time-dependent patient outcomes from hospital patient records

We describe REMIND, a data mining framework that accurately infers missing clinical information by reasoning over the entire patient record. Hospitals collect computerized patient records (CPR's) in structured (database tables) and unstructured (free text) formats. Structured clinical data in the CPR's is often poorly recorded, and information may be missing about key outcomes and processes. For instance, for a population of 344 colon cancer patients, important clinical outcomes, such as disease state and its evolution, are stored only as unstructured data (doctors' dictations) in the CPR. Raw evidence (extracted directly from the CPR) is not a good predictor of disease state. Yet by combining this evidence in a principled fashion (using methods from uncertain and temporal reasoning), REMIND accurately infers disease state sequences for recurrence, a complex time-varying outcome, for these patients. These outcomes can now be added back into the CPR in structured form.

Massive aneurysmal bone cyst of the anterior cranial fossa floor--case report

A 19-year-old male patient presented with a midline facial, nose, and forehead hard and bony swelling associated with hypertelorism. Neuroimaging revealed a massive tumor involving the anterior cranial fossa floor, which had occupied and enlarged all paranasal air sinuses, and displaced the orbits outwards and the frontal lobes of the brain superiorly. A basal transcranial route was used for radical resection of the massive and vascular tumor. Histological examination confirmed an aneurysmal bone cyst. Such tumors only rarely involve the cranial bones or paranasal air sinuses.

Prognostic factors for cerebellar astrocytomas in children: a study of 102 cases

OBJECTIVE

To evaluate the prognostic factors influencing the length of survival of pediatric patients with cerebellar astrocytomas.

METHODS

The clinical data of 102 patients under the age of 12 years with cerebellar astrocytomas were retrospectively analyzed. The radiological features, surgical findings, histology and adjuvant radiotherapy were reviewed. Patients were followed up on an outpatient basis. Computerized tomography (CT) scans of the brain were performed to detect recurrence.

RESULTS

The age of the patients at presentation varied from 10 months to 12 years. The mean age at presentation was 7 years and 11 months. The average duration of symptoms was 5.8 months. The clinical features were predominantly related to intracranial hypertension and the location of the tumor. Twenty-six tumors were located in the vermis and 76 in the cerebellar hemisphere. The brain stem was involved in 20 patients. All 102 patients had a preoperative contrast-enhanced CT scan. Midline vermian tumors were predominantly solid and enhancing, whilst the hemispheric tumors were cystic and nonenhancing. The tumors were graded into three subgroups based on histological characteristics: pilocytic astrocytoma, low-grade fibrillary astrocytoma and high-grade fibrillary astrocytoma. Total, radical and subtotal excision, as determined by the surgical impression, were performed in 82, 16 and 4 patients, respectively. Postoperative radiotherapy was administered to 12 patients. CSF diversion was carried out in 11 of 79 cases who had moderate to severe hydrocephalus.

CONCLUSIONS

Our study has shown that the location of the tumor (p < 0.05), histological grade (p < 0.001) and the extent of tumor resection (p < 0.001) have a significant and definitive relationship to the length of survival of pediatric patients with cerebellar astrocytomas. The patient's age (p > 0.05) does not influence the outcome. We could not evaluate the effect of brain stem involvement and adjuvant radiotherapy in our study because of the small sample size.

Effects of humanization and gene shuffling on immunogenicity and antigen binding of anti-TAG-72 single-chain Fvs

One major constraint in the clinical application of murine monoclonal antibodies (MAbs) is the development of a human antimurine antibody response. The immunogenicity of MAbs can be minimized by replacing nonhuman regions with corresponding human sequences. The studies reported in our article were undertaken to analyze the immunoreactivity and the immunogenicity of the CC49 single-chain antibody fragments (scFvs): (i) an scFv construct comprised of mouse CC49 VL and VH (m/m scFv), (ii) a light chain shuffled scFv with human VL (Hum4 VL) and mouse CC49 VH (h/m scFv), and (iii) a humanized scFv assembled from Hum4 VL and CC49 VH complementary determining regions (CDRs) grafted onto a VH framework of MAb 21/28' CL (h/CDR scFv). The CC49 scFvs competed for an antigen binding site with CC49 IgG in a similar fashion in a competition radioimmunoassay and were able to inhibit the binding of CC49 IgG to the antigen completely. The immunogenicity of CC49 scFvs was tested using sera with antiidiotypic antibodies to MAb CC49 obtained from patients treated by CC49 IgG in clinical trials. All tested sera exhibited the highest reactivity to the m/m scFv. However, the sera demonstrated differential reactivities to h/CDR scFv and h/m scFv. Replacement of the mouse chain in h/m scFv and h/CDR scFv decreased or completely averted serum reactivity. Our studies compared for the first time the antigen binding and immunogenicity of different scFv constructs containing the mouse, CDR grafted or human variable chains. These results indicate that the humanized CC49 scFv is potentially an important agent for imaging and therapeutic applications with TAG-72-positive tumors.

Upper and mid-ureteric stones: a prospective unrandomized comparison of retroperitoneoscopic and open ureterolithotomy

OBJECTIVES

To review our experience of retroperitoneoscopic ureterolithotomy (RPUL) and to compare the results with those from open surgery.

PATIENTS AND METHODS

Between March 1994 and mid-December 2000, 55 patients with large (mean 2.1 cm) upper and mid-ureteric calculi, and with normal renal values, underwent RPUL. In 22 patients, earlier attempts with extracorporeal shock wave lithotripsy and ureteroscopy had failed. These patients were compared with 26 (mean stone size 2.4 cm) who underwent open ureterolithotomy during the same period. The two groups had similar distributions for age, sex, stone size and stone location; most stones were calcium-based.

RESULTS

The mean operative duration and blood loss for RPUL and open surgery were 108.8 and 98.8 min, and 58.5 and 50.5 mL, respectively (not significant). The mean analgesic (pethidine) requirement and hospital stay for RPUL and open surgery were 41.1 and 96.9 mg, and 3.3 and 4.8 days, respectively (P<0.001). The duration of convalescence was significantly less after RPUL than open surgery (1.8 weeks vs 3.1). There were 10 conversions, which occurred early in the series, and one significant complication amongst patients who underwent RPUL.

CONCLUSIONS

RPUL is comparable with open surgery for operative duration and blood loss, but the laparoscopic procedure has significant advantages over open surgery for analgesia, hospital stay, recuperation and cosmesis. RPUL is a viable alternative for large upper and mid-ureteric calculi and in those patients where a previous attempt at endourological management has failed. However, the technique requires significant training and experience before good results can be obtained.

Pancreatoblastoma

Pancreatoblastoma is an extremely rare pancreatic tumor in childhood, comprising 0.5% of pancreatic non endocrine tumors. Just over 50 cases have been reported in the literature till 1997. A 10 year-old male child presented with mass abdomen of 9 months duration. USG and CT abdomen showed a large mixed density lobulated mass in abdomen anterior to, and displacing down the portal vein and splenic veins. Exploratory laparotomy revealed a large mass, arising from body and tail of pancreas, not infiltrating the adjacent structures. Complete excision of the mass along with removal of body and tail of pancreas was done. The histopathological examination revealed pancreatoblastoma. He is well without any evidence of disease 6 months after the operation. To the best of our knowledge this is the first case of pancreatoblastoma with a large size (25 x 20 x 15 cm,) weight 2.5 kg, which was localized and where complete excision was possible. The largest size reported in the literature reviews has been around 15 cm. The literature review confirms that an aggressive surgical attack on resectable pancreatoblastoma may often be curative. The role of adjuvant chemotherapy or radiotherapy is still under discussion due to small number of patients treated as yet.

Specific inhibition of cyclooxygenase-2 (COX-2) expression by dietary curcumin in HT-29 human colon cancer cells

Curcumin, a major yellow pigment and active component of turmeric, has been shown to possess anti-inflammatory and anti-cancer activities. Cyclooxygenase (COX)-2 plays an important role in colon carcinogenesis. To investigate the effect of curcumin on COX-2 expression, we treated HT-29 human colon cancer cells with various concentrations of curcumin. Curcumin inhibited the cell growth of HT-29 cells in a concentration- and time-dependent manner. Curcumin markedly inhibited the mRNA and protein expression of COX-2, but not COX-1. These data suggest that a non-toxic concentration of curcumin has a significant effect on the in vitro growth of HT-29 cells, specifically inhibits COX-2 expression, and may have value as a safe chemopreventive agent for colon cancer.

Oxidative stress increases frameshift mutations in human colorectal cancer cells

Chronic inflammation in the gastrointestinal tract increases the risk for development of cancer by an incompletely understood pathway, which may involve microsatellite instability (MSI). Low frequency of MSI referred to as "MSI-L" occurs frequently in chronically inflamed nonneoplastic tissue. In this work, we have tested the hypothesis that oxidative stress may induce the accumulation of frameshift mutations in human microsatellite DNA. Mismatch repair (MMR)-proficient HCT116+chr3 and MMR-deficient HCT116 cells were transfected with pCMV-(CA)13-EGFP, a plasmid that contains a (CA)13 dinucleotide repeat, which disrupts the reading frame of the downstream enhanced green fluorescent protein gene. A dose-dependent increase in frameshift mutations restoring the enhanced green fluorescent protein reading frame was detected in HCT116 by flow cytometry. At 1 mM H2O2, the mutant fraction was 9-fold higher than that in mock-treated control cells. Although demonstrating stability at lower H2O2 concentrations, MMR-proficient HCT116+chr3 cells accumulated mutations at the 1 mM H2O2 level (4.1-fold above mock-treated control). No significant mutations were detected when HCT116 cells were transfected with the pCMV-(N)26-EGFP construct that contains 26 nucleotides in a random sequence. These data indicate that oxidative stress is a potential mutagen leading to accumulation of frameshift mutations and may contribute to MSI in the setting of chronic inflammation.

An unusual periaqueductal glioma: A short report

A rare case of periaqueductal glioma with an unusual radiological picture is presented. A forty-five year old male presented with progressive bilateral third and eighth nerve paresis. Magnetic resonance imaging (MRI) revealed a diffuse periaqueductal tumour with sparing of aqueduct and no hydrocephalus. MRI is a useful adjunct in such a situation for contemplating appropriate modality of treatment.

Multiple giant synovial chondromatosis of the knee

This report describes an unusual presentation of monoarticular synovial chondromatosis of the knee. In this case, multiple giant chondroid nodules presented as a painless soft tissue mass. There was no calcification but bony erosion was seen on MR scan. Such lesions may mimic a malignant neoplasm and pose a diagnostic problem.

Mucin antibodies - new tools in diagnosis and therapy of cancer

Many cancer and diseased cells are distinguished from their normal counterparts by an altered expression of cell-surface epitopes. One family of molecules that show altered expression on tumor cells is mucins (MUC). Unlike normal tissue where MUC exists as heavily glycosylated form, the disease- or tumor-associated MUC molecules are underglycosylated. Such underglycosylation of the core protein in cancer tissues exposes new epitopes on the cell surface that are unique to cancer tissues. Several monoclonal antibodies (Mabs) have been generated against these normal and tumor-associated mucins. Enzymatic fragments of Mabs like F(ab')2 and Fab have shown improved clinical utility for diagnosis, imaging, and therapy of cancer. Genetic-engineering methods have been used to design antibody fragments exhibiting high functional affinity, good tumor localization, and rapid clearance from the blood stream thus minimizing radiation exposure to the normal tissues. Such recombinant fragments have shown encouraging results in preclinical studies using xenografted tumor bearing mice and present a whole new avenue for radioimmunotherapy and diagnosis of cancer.

Pathological laughter as a presenting symptom of petroclival meningioma--case report

A 35-year-old male presented with symptoms of 'pathological laughter' occurring for 6 months and progressive ataxia and right facial nerve paresis for 2 months. Neuroimaging revealed a large petroclival meningioma. The tumor was well defined and only moderately vascular, and could be relatively easily resected. The symptom of pathological laughter disappeared immediately and his gait improved to normal within a week of surgery. Pathological laughter as a presenting symptom of petroclival meningioma is extremely rare. The symptom of pathological laughter may have localizing value.

99mTc-labeled divalent and tetravalent CC49 single-chain Fv's: novel imaging agents for rapid in vivo localization of human colon carcinoma

Radioimmunopharmaceutical agents enabling rapid high-resolution imaging, high tumor-to-background ratios, and minimal immunogenicity are being sought for cancer diagnosis and imaging. Genetic engineering techniques have allowed the design of single-chain Fv's (scFv's) of monoclonal antibodies (mAbs) recognizing tumor-associated antigens. These scFv's show good tumor targeting and biodistribution properties in vivo, indicating their potential as imaging agents when labeled with a suitable radionuclide.

METHODS

Divalent (sc(Fv)(2)) and tetravalent ([sc(Fv)(2)](2)) scFv's of mAb CC49 were evaluated for radioimmunolocalization of LS-174T colon carcinoma xenografts in athymic mice. scFv's were radiolabeled with (99m)Tc by way of the bifunctional chelator succinimidyl-6-hydrazinonicotinate hydrochloride using tricine as the transchelator. The immunoreactivity and in vitro stability of the scFv's were analyzed after radiolabeling. Biodistribution and pharmacokinetic studies were performed to determine the tumor-targeting potential of the radiolabeled scFv's. Whole-mouse autoradiography illustrated the possible application of these (99m)Tc-labeled multivalent scFv's for imaging.

RESULTS

The radiolabeling procedure gave > or =95% radiometal incorporation, with a specific activity of >74 MBq/mg scFv. In solid-phase radioimmunoassay, both sc(Fv)(2) and [sc(Fv)(2)](2) exhibited 75%-85% immunoreactivity, with nonspecific binding between 0.8% and 1.2%. Size-exclusion high-performance liquid chromatography showed sc(Fv)(2) as a 60-kDa protein and [sc(Fv)(2)](2) as a 120-kDa protein. Blood clearance studies showed the elimination half-life of (99m)Tc-labeled sc(Fv)(2) as 144 min and that of [sc(Fv)(2)](2) as 307 min. Whole-body clearance studies confirmed the rapid elimination of scFv's, with half-lives of 184 +/- 19 min for sc(Fv)(2) and 265 +/- 39 min for [sc(Fv)(2)](2) (P < 0.001). At 6 h after administration, the tumor localization was 7.2 +/- 0.7 percentage injected dose per gram of tumor (%ID/g) for (99m)Tc-sc(Fv)(2). (99m)Tc-[sc(Fv)(2)](2) showed a tumor uptake of 19.1 +/- 1.1 %ID/g at the same time; the amount of radioactivity in the tumors was 4-fold higher than in the spleen and kidneys and 2-fold higher than in the liver. Macroautoradiography performed at 6 and 16 h after administration clearly detected the tumor with both scFv's.

CONCLUSION

(99m)Tc-labeled multivalent scFv's show good tumor-targeting characteristics and high radiolocalization indices (tumor-to-background ratio). These reagents, therefore, have the potential for use in clinical imaging studies of cancer in the field of nuclear medicine.

Cloning and characterization of human cathepsin L promoter

Cathepsin L is a lysosomal cysteine protease, which is over-expressed and secreted by malignant cells. It is very potent in degrading collagen, elastin, laminin and other components of the basement membrane and, therefore, has been implicated in tumor invasion and metastasis. The structural portion of the human cathepsin L (hCATL) gene was cloned to elucidate its genomic organization (Chauhan et al., J. Biol. Chem. 218 (1993) 1039). In the present study, a 1.90 kb DNA fragment, containing 1825 bp of the 5' upstream region of hCATL and 75 bases of the first exon of the hCATL, was amplified by PCR from an adaptor ligated placental genomic library. This fragment has been demonstrated to exhibit promoter activity by luciferase reporter assays. Sequence analysis of this fragment revealed the presence of approximately 29 different putative transcription factor binding sites. Several of them like AP-4, GATA-1, Lmo2, CEBPB, MZF-1, NF-AT, etc. were present more than once in this region. However, a consensus CAAT box but no consensus TATA box was found within the 1.0 kb upstream of exon 1. The transcription initiation site of hCATL, using placental total RNA, was mapped to a single adenine residue 289 bases upstream of the ATG codon.

Posterior cranial fossa dermoid in association with craniovertebral and cervical spinal anomaly: report of two cases

Two patients, a 12-year-old girl and an 8-year-old boy, with congenital craniovertebral anomaly and Klippel-Feil syndrome also had a posterior cranial fossa dermoid. The association of these two discrete pathological lesions in the same individual is extremely rare. As both lesions are related to an embryological disorder, issues regarding the possible stage of dysgenesis are analyzed. The treatment options in such cases are discussed.

Evaluation of laparoscopic retroperitoneal surgery in urinary stone disease

PURPOSE

To assess the safety and effectiveness of laparoscopic retroperitoneal surgery and attempt to define its role in the management of urolithiasis.

PATIENTS AND METHODS

Laparoscopic retroperitoneal surgery (LRS) was undertaken in 72 male and 42 female patients with calculous disease from March 1994 to April 2000 for variety of indications that otherwise would have made them candidates for conventional open surgery. Some of these patients were subjected to retroperitoneoscopic ureterolithotomy (RPUL) (40 patients) and retroperitoneoscopic pyelolithomy (RPPL) (7 patients). Retroperitoneoscopic nephrectomy (RPN) and nephroureterectomy (RPNUT) for a nonfunctioning renal unit secondary to renal and or ureteral calculi was done in 53 and 14 patients, respectively. Most of the procedures were performed with three 10-mm ports. In some cases, an additional 5-mm port was used.

RESULTS

The procedure was successful in 75%, 71%, 90.5%, and 86% of cases subjected to RPUL, RPPL, RPN, and RPNUT, respectively. The mean operating time for RPUL was 106.3 minutes and for RPPL was 108.2 minutes, whereas it was 99.7 minutes for RPN and 147 minutes for RPNUT of nonfunctioning kidneys secondary to calculous disease. The major complications encountered were colon injury in one patient with calculous pyonephrosis who had dense adhesions and injury to the external iliac artery in another patient having RPUL. The mean blood loss was 69.8, 127.2, 135.6, and 206.5 mL, respectively, for RPUL, RPPL, RPN, and RPNUT. The average hospital ranged from 3 to 4 days.

CONCLUSIONS

Laparoscopic retroperitoneal surgery has a definite role in the management of patients requiring open surgery for calculous disease. It is safe and feasible in spite of the dense adhesions that are frequently encountered in such patients. Often, previous attempts at treatment with shockwave lithotripsy or endourologic procedures also lead to inflammation and adhesions, making surgery difficult. However, these problems can be dealt with by LRS with good results.

Sinus pericranii in the frontal region: a case report

Sinus pericranii is a rare vascular anomaly. A case of sinus pericranii at the nasion with an orbital extension is presented. The drainage was into the superior sagittal sinus. The pathogenesis is discussed and the literature is reviewed.

Tuning DNA "strings": modulating the rate of DNA replication with mechanical tension

Recent experiments have measured the rate of replication of DNA catalyzed by a single enzyme moving along a stretched template strand. The dependence on tension was interpreted as evidence that T7 and related DNA polymerases convert two (n = 2) or more single-stranded template bases to double helix geometry in the polymerization site during each catalytic cycle. However, we find structural data on the T7 enzyme--template complex indicate n = 1. We also present a model for the "tuning" of replication rate by mechanical tension. This model considers only local interactions in the neighborhood of the enzyme, unlike previous models that use stretching curves for the entire polymer chain. Our results, with n = 1, reconcile force-dependent replication rate studies with structural data on DNA polymerase complexes.

Surgery on anterior foramen magnum meningiomas using a conventional posterior suboccipital approach: a report on an experience with 17 cases

OBJECTIVE

The advantages of a posterior "conventional" suboccipital approach with a midline incision over lateral, anterolateral, and anterior approaches to anteriorly placed foramen magnum meningiomas are discussed.

METHODS

From 1991 to March 2000, 17 patients with foramen magnum meningiomas arising from the anterior or anterolateral rim of the foramen magnum underwent operations in the Department of Neurosurgery at King Edward Memorial Hospital and Seth G.S. Medical College. All patients were operated on in a semi-sitting position by use of a conventional suboccipital approach with a midline incision and extension of the craniectomy laterally toward the side of the tumor up to the occipital condyle.

RESULTS

The patients ranged in age from 17 to 72 years, and the tumors ranged in size from 2.1 to 3.8 cm. The intradural vertebral artery was at least partially encased on one side in eight patients and on both sides in two patients. The brainstem was displaced predominantly posteriorly in each patient. A partial condylar resection was performed in two cases to enhance the exposure. Total tumor resection was achieved in 14 patients, and a subtotal resection of the tumor was performed in the other 3 patients. In one patient, a small part of the tumor was missed inadvertently, and in the other two patients, part of the tumor in relation to the vertebral artery and posterior inferior cerebellar artery was deliberately left behind. After surgery, one patient developed exaggerated lower cranial nerve weakness. There was no significant postoperative complication in the remainder of the patients, and their conditions improved after surgery. The average length of follow-up is 43 months, and there has been no recurrence of the tumor or growth of the residual tumor.

CONCLUSION

From our experience, we conclude that a large majority of anterior foramen magnum meningiomas can be excised with a lateral suboccipital approach and meticulous microsurgical techniques.