Edge enhancement of ECG-gated cardiac images using directional masks

ECG-gated images were processed by a computer using a nonlinear digital filter and directional masks to improve delineation of cardiac chamber boundaries and identification of the aortic and mitral valve planes. This technique proved to be satisfactory in 30 patients with documented coronary or valvular heart disease.     

Mesh migration into the bladder after TEP repair: a rare case report

Mesh migration after laparoscopic inguinal hernia repair is an unusual complication. We report a case of a 45-year-old man with persistent discharging of abdominal wall sinus after total extraperitoneal inguinal hernia repair. The patient underwent exploration and excision of the sinus tract with removal of the embedded mesh. A part of the mesh had migrated into the urinary bladder. Partial cystectomy with excision of wall containing the mesh was performed.     

A rare psoas hernia: endoscopic diagnosis and management

Of the various traumatic injuries associated with blunt abdominal trauma, traumatic hernias form a rare and small group. We present a case report of a hernia in the psoas muscle in a 26-year-old lady diagnosed during extraperitoneal repair for inguinal hernia. The hernia was managed laparoscopically by reduction of contents and mesh placement over the defect. This is the first such case reported in the literature till date.     

Prophylactic bilateral mastectomy: patterns of practice

BACKGROUND: Many women who are at an elevated risk of developing breast carcinoma choose prophylactic mastectomy to decrease their risk. We conducted a population-based study to review the indications for, and patterns of practice of prophylactic mastectomy in Ontario, Canada, since 1991. METHODS: A medical chart review was conducted at 33 hospitals that were identified as having conducted at least one prophylactic mastectomy. All bilateral mastectomy patients with no diagnosis of invasive or in situ breast carcinoma were eligible. RESULTS: The number of prophylactic bilateral mastectomies performed varied from 6 to 19. The mean age of women undergoing prophylactic mastectomy was 43.5 years. Eighty percent of the women had prophylactic mastectomy performed because of a family history of breast carcinoma (89 of 99) or because of a known BRCA1 or BRCA2 mutation (10 of 99). Twenty percent of the women had no family history, but had the surgery for other benign breast conditions. Women with a family history of breast carcinoma were much more likely to have a total mastectomy (89%) than a subcutaneous mastectomy (11%). Sixty percent of the women had reconstructive surgery following mastectomy. CONCLUSIONS: Prophylactic mastectomy is not performed on a large scale. The introduction of genetic testing for BRCA1 and BRCA2 has the potential to change the patterns of practice for prophylactic mastectomy.     

Cavernous haemangioma in the interpeduncular cistern: case report and review of literature

A rare case of a cavernous haemangioma in the interpeduncular cistern is reported. The patient, forty-five year old male presented with excruciating left sided trigeminal neuralgia and diplopia for the past one year. Examination revealed left third and fifth nerve paresis. Magnetic resonance imaging showed a well-defined, lobulated tumour in the interpeduncular cistern. The tumour was totally excised through a subtemporal route. Histology of the tumour revealed a cavernous haemangioma. Extracerebral location for a cavernous haemangioma is rare. An interpeduncular cavernous haemangioma has never been reported earlier in literature. The clinical and radiological features are discussed and relevant literature is briefly 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.