Localized molecular orbital description of nitrogen lone pairs

The Boys localization procedure is applied to several molecules possessing nitrogen lone pairs. The Boys structures show a tendency for the N lone pairs to participate in bonding to nearby electron sinks. For example, the Boys structure for planar formamide has two equivalent tau-bond orbitals between the carbonyl carbon and nitrogen atoms. The change in this description with variation of geometry at nitrogen is treated, and analogous Edmiston-Ruedenberg localizations on formamide are included for comparison.

Safety and anticoagulation effect of a low-dose combination of warfarin and aspirin in clinically stable coronary artery disease. Coumadin Aspirin Reinfarction (CARS) Pilot Study Group

The hypothesis that the combination of low-dose aspirin and warfarin therapy is more effective than aspirin alone in secondary prophylaxis after myocardial infarction is to be examined in the Coumadin Aspirin Reinfarction Study. This pilot study addressed the safety and anticoagulation effect of a fixed, low-dose combination in 114 patients (aged 64 +/- 8 years, 85% men) with stable coronary artery disease receiving 3 mg of warfarin plus 80 mg of aspirin daily for 8 weeks. The international normalized ratio (INR) was measured within 72 hours of initial therapy, and weekly. Of the 110 patients with evaluable INRs, 87 patients (79%) maintained the 3 + 80 mg combination, 19 (17%) had the dose reduced to 1 mg warfarin + 80 mg aspirin, and 4 (4%) discontinued therapy because of a confirmed INR of > or = 4.5. At steady state, patients had INRs of 1.48 +/- 0.41 (3 + 80 mg group) and 1.21 +/- 0.23 (1 + 80 mg group), and inter- and intra-patient variability (estimated by the mean of the between- and within-patient SDs at steady state) was 0.49 +/- 0.08 and 0.13 +/- 0.14, respectively. There was no apparent effect of age on INR distribution. Microscopic hematuria was the most frequent (20%) adverse clinical event, but was unrelated to the INR. Three patients required discontinuation of therapy because of bleeding events (persistent hematuria and epistaxis). A fixed low-dose combination of warfarin and aspirin results in a predictable and stable increase in the INR in a large proportion of patients with coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adiposis dolorosa (Dercum's disease): liposuction as an effective form of treatment

The clinical picture of adiposis dolorosa makes a lasting impression on the examining physician. The patient is typically an obese, asthenic woman who appears to have a low pain threshold. She has an unusual distribution of fatty tumors, and her complaint of pain in these tumors seems out of proportion to the physical findings. Alcoholism, emotional instability, and depression are common, and narcotic pain medicine is frequently requested. The patient is easily dismissed as a malingerer after a brief examination. However, liposuctioning of the painful fatty tumors appears to be both practical and effective. While adiposis dolorosa is an unusual disease, it is one that plastic surgeons can recognize and treat.

Late revision of fibular malunion in ankle fractures

Eleven patients with fibular malunion after ankle fracture healed with stiff, painful joints and radiographic evidence of fibular malunion, diastasis of the ankle mortice, and talar tilt. Reconstruction was performed by mobilizing the fibula (by osteotomy or through the old fracture site), lengthening the fibula, and restoring the ankle mortice anatomically. The operation was done three months to three years after the initial fracture in patients ranging in age from 26 to 52 years. The average follow-up period was 3.3 years. Radiographically, seven patients had the ankle joint restored anatomically. Four patients had residual talar tilt. On clinical assessment, eight patients were rated as good, two fair and improving, and one poor resulting in fusion. Good functional results were maintained at long-term follow-up examination. The factors that determined the success of the revision were the duration of the malunion, the quality of the reduction achieved, and the condition of the articular cartilage at the time of revision. Late correction of the malunited fibula with diastasis of the ankle mortice is an effective means of salvaging function in a joint otherwise destined to be stiff and painful.

Clonazepam therapy in reading epilepsy

A 19-year-old man had reading-induced epilepsy; generalized seizures were preceded by myoclonus of the jaw. Although reading epilepsy is usually refractory to anticonvulsant therapy, treatment with clonazepam resulted in complete control of the involuntary movements precipitated by reading.

Tetracycline therapy for acne: incidence of vaginitis

We have noted an incidence of vaginitis of 5 percent in women of childbearing age taking tetracycline for acne. We believe that tetracycline is a remarkably safe medication, and that the incidence of side effects from its use is low especially when instruction is given to the patient regarding its proper ingestion.

Anterior mediastinotomy

The indications and techniques for performing the operation of anterior mediastinotomy are described. In the years 1966-71, 116 anterior mediastinotomies were done. The results of these are presented.

In 36 patients the operation was done to provide a histological diagnosis in benign conditions. In 51 patients, with probable carcinoma but normal bronchoscopy, mediastinotomy was done to establish a diagnosis and assess operability; 43 had involved mediastinal nodes proven on histology. In a further 29 patients, with positive bronchoscopic biopsies, mediastinotomy was done to assess operability alone. In all, 14 patients (17·5%) were judged suitable for thoracotomy. Of these, nine had operable disease while five were found to be inoperable.

The incidence of complications of the operation was low (11%). These were mostly minor, There were no deaths. Most patients, after anterior mediastinotomy alone, were fit for discharge 48 to 72 hours after the operation.

The value of an operation that provides both diagnosis and assessment of mediastinum, lung, and pleura is discussed. The operation of anterior mediastinotomy is compared with mediastinoscopy and, in our opinion, the superiority of the former is demonstrated.

Early warning of rejection?

The urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), beta-galactosidase (GAL), beta-glucosidase (GLU), and alkaline phosphatase (AP) was studied in 83 patients with renal allografts. Thirty of these patients had stable graft function and their urinary enzyme levels provided a range of normal values. Urinary lactic dehydrogenase (LDH) was estimated in 29 normal subjects and in 11 patients with renal allografts. Serum values for the five enzymes were also obtained. Urinary NAG excretion was abnormally high in 16 out of 17 (94%) episodes of acute rejection. The other urinary enzymes were raised less frequently. In nine patients studied before the onset of rejection urinary NAG activity rose up to three weeks before changes in other tests of renal function. Serum enzyme levels were not found to be of value in the diagnosis of rejection.

Prolapse of the ileum through the rectum and anal canal

A case of prolapse of the ileum through a tear in the rectal wall and the anus is presented and 11 previous cases found in the literature are reviewed. The aetiology and the management of the condition are discussed.

Hydrocortisone arthropathy--an experimental investigation

Images