Purification, Crystallization, and Preliminary Crystallographic Studies of Human As(III) S-Adenosylmethionine Methyltransferase (hAS3MT).

Exposure to environmental arsenic is associated with serious of health issues such as cancer, diabetes and developmental delays in infants and children. In human liver, As(III) S-adenosylmethionine methyl transferase (hAS3MT) (EC 2.1.1.137) was proposed to be an detoxification process by methylation of inorganic arsenite into pentavalent methyl MAs(V) and dimethyl arsenite DMAs(V). More recently the first product was shown to be highly toxic and potentially carcinogenic trivalent methylarsenite (MAs(III)). Our studies are designed to elucidate the mechanism of AS3MT and its contribution to arsenic-related diseases. Here, we report the first crystallization and preliminary X-ray diffraction analysis of the human AS3MT enzyme. The crystals belong to the monoclinic P1211 space group with unit cell parameters of a = 135.03 Å, b = 260.44 Å, c = 279.03 Å, α = 90.00°, ß = 93.36°, γ = 90.00°.

Expanding the role of radiographers in reporting suspected lung cancer: A cost-effectiveness analysis using a decision tree model.

INTRODUCTION: To assess whether an enhanced role for radiographers in reporting lung cancer chest radiographs is cost-effective. METHODS: Costs and outcomes of chest radiograph reporting by reporting radiographer or by a radiologist were compared using a decision tree model. The model followed patients from an initial chest radiographs for suspected lung cancer to the provision of cancer care in positive cases. Sensitivity and specificity of reporting for radiographers and radiologists were derived from a recent trial. Treatment costs and quality adjusted life expectancy were estimated over five years for those diagnosed. Deterministic and probabilistic sensitivity analyses were used to test the robustness of inference to parameter uncertainty. RESULTS: For 1000 simulated patients, radiographer reporting decreased detection costs by £8500 and detected 10.3 more cases at initial presentation. After including treatment costs and outcomes, radiographer reporting remained cheaper than radiologist reporting and resulted in 1.4 additional QALYs per 1000 screened patients. Probabilistic analysis indicated a 98% likelihood that radiographer reporting is cheaper and more effective than radiologist reporting after inclusion of treatment costs and outcomes. CONCLUSION: Radiographer reporting is a cost-effective alternative to radiologist reporting in lung cancer diagnosis. Further work is needed to support the adoption of radiographer's reporting pathway in diagnosis of lung cancer suspected patients.

A prospective observational study of the use of desflurane anesthesia in Indian adult inpatients undergoing surgery: The Registry in India on Suprane Emergence registry.

BACKGROUND AND AIMS: Limited registry studies are available on the use of anesthetic agents. This registry was conducted to evaluate emergence outcomes in Indian adult patients undergoing surgery with desflurane anesthesia. MATERIAL AND METHODS: This multicenter, prospective, non-interventional, observational study (Registry in India on Suprane Emergence [RISE] registry) included adult inpatients who received desflurane as general anesthetic for surgical procedure of ≥2 h. Patients were stratified by age into three groups: ≥18-40 years, ≥41-65 years, and >65 years. Data on patients' demographics, practice, and usage pattern of medications were collected. The primary efficacy outcomes were time to extubation, time to response to verbal command, and time to orientation. RESULTS: Of 236 patients screened, 201 (≥18-40 years, n = 70; ≥41-65 years, n = 65; >65 years, n = 66) were enrolled in the study. Mean time to extubation observed in ≥18-40 years group was 7.2 ± 4.1 min, ≥41-65 years was 11.6 ± 8.99 min, and >65 years was 12.0 ± 10.5 min. Mean time to response to verbal command was 7.4 ± 4.3 min for ≥18-40 years, 10.9 ± 8.5 min for ≥41-65 years, and 10.0 ± 5.4 min for >65 years. Mean time to orientation was 13.0 ± 7.0 min for ≥18-40 years, 16.1 ± 12.0 min for ≥41-65 years, and 17.0 ± 8.6 min for >65 years. Incidence of nausea and retching/vomiting was observed in 8% of patients each in the postoperative period, and these complications were seen more in the >65 years age group. Overall, desflurane treatment maintained hemodynamic stability and no major airway events were reported. CONCLUSIONS: The RISE registry data suggest that desflurane-based anesthesia provides early recovery with stable hemodynamics without any airway adverse events, in a wide variety of surgical procedures.

Malignant orbital teratoma in a neonate: A clinicopathological case report.

Teratoma of the orbit is rare; very few cases have been published in literature. A case of orbital teratoma in a neonate is presented where the proptosis was massive enough to obscure the eyeball. Clinically, the diagnosis of teratoma was considered. As there was no possibility of salvaging the eye, exenteration of the orbit was done. Orbital teratomas are generally benign. Histopathological examination revealed the features of malignant teratoma.

AN AUDIT OF THE CURRENT PRACTICES OF AIRWAY MANAGEMENT IN PATIENTS UNDERGOING SURGERY FOR ATLANTO-AXIAL DISLOCATION IN A SINGLE INSTITUTION.

BACKGROUND: Patients with atlanto axial dislocation (AAD) undergo stabilisation procedures under general anesthesia. Airway management in these patients is difficult as cervical spine movements during laryngoscopy can worsen spinal cord damage. Though multiple airway devices are used to intubate the trachea of these patients, there is no evidence of superiority of one technique over another. This retrospective study was designed to audit the practice of airway management during surgery for AAD over a 5 year period, starting from 2006 till 2011. METHODS: Patients' demographics, airway intervention techniques, types of surgical procedures, postoperative neurological and respiratory deterioration were recorded from the case files. Association between the types of airway interventions and the postoperative neurological and respiratory deterioration were analysed. RESULTS: One hundred and six patients underwent surgery for AAD during the study period. Sixty one percent of the patients were intubated with the help of a fiberoptic bronchoscope (FOB) and among them 15% received general anesthesia to facilitate FOB. Eighteen patients developed neurological deterioration and 15 patients developed respiratory weakness requiring ventilation postoperatively. Congenital AAD patients had higher chances for extubation at the end of surgery when intubated using FOB (p = 0.007). Among the AAD patients, female gender had significantly higher incidence of neurological deterioration compared to males. CONCLUSION: In the current audit, there was no correlation between the perioperative variables and postoperative respiratory and neurological deterioration. Most of the respiratory problems occurred between 2-5 postoperative days stressing the need for extended intensive postoperative monitoring of these patients.

Solitary fibrous tumor of the tentorium: a case report.

The authors describe the clinical and pathological features of a solitary fibrous tumor of the tentorium, a rare location for the tumor in the CNS. A 52-year-old lady presented to the neurosurgical services with headache of four months and vertigo of one and a half months duration. On examination, she had left-sided cerebellar signs and bilateral papilloedema. Cranial MR imaging showed an enhancing tumor based on the left tentorium. Clinical impression was a meningioma. The patient underwent left suboccipital craniectomy. The tumor was firm and vascular, extending above the tent through a defect. Total excision was achieved. The correct diagnosis of solitary fibrous tumor could be made only by histopathology. Solitary fibrous tumors of the tentorium, though rare, should be included in the differential diagnosis of dural based masses.

Pulse-plethysmographic variables in hemodynamic assessment during mannitol infusion.

Plethysmographic signal using pulse oximetry may be used to assess fluid status of patients during surgery as it resembles arterial pressure waveform. This will avoid placement of invasive arterial lines. This study was designed to find out whether intravascular volume changes induced by mannitol bolus in neurosurgical patients are detected by variations in arterial pressure and plethysmographic waveforms and also to assess the strength of correlation between different variables derived from these two waveforms. The time difference between the onset of arterial and plethysmographic waveforms as means of significant hemodynamic changes was also evaluated. Forty one adult ASA I and II neurosurgical patients requiring mannitol infusion were recruited. Arterial line and plethysmographic probe were placed in the same limb. Digitized waveforms were collected before, at the end, and 15, 30 and 60 min after mannitol infusion. Using MATLAB, the following parameters were collected for three consecutive respiratory cycles,-systolic pressure variation (SPV), pulse pressure variation (PPV), plethysmographic peak variation (Pl-PV), plethysmographic amplitude variation (Pl-AV) and blood pressure-plethysmographic time lag (BP-Pleth time lag). Changes in above parameters over the study period were studied using repeated measure analysis of variance. Correlation between the parameters was analysed. SPV and Pl-PV showed significant increase at 15, 30 and 60 min compared to end of mannitol infusion (P < 0.01 for SPV; P < 0.05 for Pl-PV). PPV and Pl-AV showed significant increase only at 30 min (P < 0.05). The correlation between ∆SPV-∆Pl-PV, ∆PPV-∆Pl-AV and ∆SPV-∆BP-Pleth time lag were significant (r = 0.3; P < 0.01). SPV and time lag had no significant interaction. Pl-PV correlates well with SPV following mannitol infusion and can be used as an alternative to SPV. (BP-Pleth) time-lag promises to be an important parameter in assessing the state of peripheral vascular resistance and deserves further investigation.

Primary myxopapillary ependymoma of the fourth ventricle with cartilaginous metaplasia: a case report and review of the literature.

Myxopapillary ependymoma (MPE), which is a benign histological subtype of ependymoma, is found predominantly in the cauda equina region. It occurs rarely in the brain and mostly as a metastatic deposit from a spinal lesion. The occurrence of primary intracranial MPE is exceptional, with only 11 cases reported to date. We report an additional case of intracranial MPE, which is the third reported case in the fourth ventricle. The tumor manifested in a 50-year-old lady, who presented with features of raised intracranial pressure. A gross total resection of the tumor was achieved. Histologically, the tumor had characteristic features of MPE with focal metaplastic cartilaginous deposit. On further evaluation, there was no evidence of a primary tumor in the spinal cord. Intracranial MPE needs further evaluation by craniospinal MRI to exclude an unrecognized primary in the spinal region, which could warrant surgical attention.

Primary diffuse leptomeningeal gliomatosis.

A 20-year-old woman with a history of seizures presented symptoms of walking difficulties for the past six months. Clinical examination was suggestive of a craniovertebral junction anomaly. A cerebrospinal fluid study showed mild protein elevation with no evidence of an infective pathology. Craniospinal MRI revealed diffuse nodular leptomeningeal enhancement of the brain and spinal cord. Histopathological examination was suggestive of a low-grade glioma, and the patient was diagnosed with primary diffuse leptomeningeal gliomatosis. So far, the patient has survived for more than 110 months without aggressive therapy.

Lidocaine infiltration of the scalp does not completely abolish increased intraocular pressure due to skull pin insertion.

Insertion of skull pins results in haemodynamic perturbations, which can be blunted by local anaesthetic infiltration of the pin sites. No study has assessed the effects on intraocular pressure. General anaesthesia was induced in 71 patients undergoing cervical spine surgery with attachment of Gardner Wells tongs to the skull. Skull pins were attached five minutes after induction following either saline (group I, 35 patients) or lidocaine (group II, 36 patients) infiltration of scalp. Intraocular pressure, mean arterial pressure and heart rate were recorded before (baseline), immediately after, and 60 s following pin insertion and analysed statistically. Insertion of pins increased intraocular pressure in both groups (from 8.4+/-2.7 to 14.2+/-3.0 mmHg in group I, and from 8.8+/-2.3 to 12.7+/-2.7 mmHg in group II, P < 0.001), which persisted even at 60 s but the increase was significantly greater in group I. Insertion of pins significantly increased blood pressure in group I only. We conclude that lidocaine infiltration at the skull pin sites for Gardner Wells tong attachment fails to completely abolish increased intraocular pressure.

Inadvertent insertion of nasogastric tube into the brain.

An unusual case of a nasogastric (Ryle's) tube inserted in the brain in a patient having severe head injury with skull base fractures is reported here along with a brief review of literature. A 35 years male was referred from a peripheral institute following head trauma with endotracheal tube and nasogastric tube in situ. A CT scan of the brain showed multiple skull base fractures and a high parietal extradural hematoma. It also revealed that the nasogastric tube had inadvertently found its way into the brain through the lamina cribrosa of the ethmoid bone. The tube was removed under aseptic conditions in the operation theatre but the patient expired on day 2 of admission due to the head injuries sustained.