Camptocormia: a biomechanical analysis. A case report.

Although camptocormia, a conversion disorder associated with the disability of severely forward-bent posture, has been reported in the literature, to date there has been no report of a detailed kinematic or biomechanical analysis of this disability. Presented is a 47-yr-old male engineer with severely forward-bent posture during walking. One year ago, after playing tennis, he developed low back pain followed by a sensation that to walk comfortably he had to assume a forward-bent posture.

What's Different About Syncope in the Aged?

Syncope is a common and highly morbid syndrome with unique features in the elderly population. Syncope in the elderly is more likely due to the accumulation of multiple pathological conditions which threaten cerebral oxygen delivery, then to single diseases. Furthermore, age-related changes in blood pressure homeostasis make older patients more susceptible to hypotension during situational stresses such as posture change, eating a meal, or taking medications.

THE MECHANISM OF ENZYME-INHIBITOR-SUBSTRATE REACTIONS : ILLUSTRATED BY THE CHOLINESTERASE-PHYSOSTIGMINE-ACETYLCHOLINE SYSTEM.

The mechanism of enzyme-inhibitor-substrate reactions has been analyzed from a theoretical standpoint and illustrated by data from the system cholinesterase-physostigmine-acetylcholine. This treatment is by no means limited to a single system but should be generally applicable to others of similar type. Competitive enzyme-inhibitor-substrate systems show the same characteristic "zones of behavior" already demonstrated for non-competitive systems by Straus and Goldstein.

THE EFFECT OF CARBON DIOXIDE TENSION ON THE METABOLISM OF CEREBRAL CORTEX AND MEDULLA OBLONGATA.

Manometric measurements were made of oxygen uptake (Q(O(O2) )) and aerobic lactic acid output (Q(G)) by slices of cerebral cortex and medulla oblongata of the cat in the presence of mixtures of 1, 5, and 20 volumes per cent of carbon dioxide in oxygen. The concentrations of NaHCO(3) and NaCl in the medium were varied to maintain constant pH and sodium ion concentrations. The calcium ion concentration was 0.

ZONE BEHAVIOR OF ENZYMES : ILLUSTRATED BY THE EFFECT OF DISSOCIATION CONSTANT AND DILUTION ON THE SYSTEM CHOLINESTERASE-PHYSOSTIGMINE.

1. The kinetics of the reversible combination of one enzyme center with one molecule of a substrate or inhibitor is treated as a true bimolecular instead of a pseudomonomolecular reaction. The general equations describing such a reaction are presented and analyzed algebraically and graphically.

THE EFFECT OF CARBON DIOXIDE TENSION ON TISSUE METABOLISM (RETINA).

The metabolism of rat retina was found to be sensitive to the concentration of the carbon dioxide-bicarbonate buffer system. Increasing the carbon dioxide from 1 per cent to 5 per cent at constant pH nearly doubled both respiration and glycolysis. Increasing the carbon dioxide at constant pH from 5 per cent to 20 per cent had no effect on glycolysis, but depressed the Q(O(O2) ) from 31 to 19.

THE EFFECT OF LOW OXYGEN TENSION ON TISSUE METABOLISM (RETINA).

Lactic acid production by rat retina in a medium containing phosphate was studied chemically. One half as much lactic acid was found as in a medium containing bicarbonate. In our experience the rate of respiration in a phosphate medium was sensitive to oxygen tension, for it was 38 per cent lower at 10 per cent and 51 per cent lower at 5 per cent oxygen than at 100 per cent oxygen.

DEMONSTRATION OF AGGLUTININS FOR BARTONELLA BACILLIFORMIS.

1. Methods of preparing a satisfactory antigen having been developed, a technique for performing an agglutination test with B. bacilliformis is made available.

FATAL INFECTION OF IRRADIATED WHITE MICE WITH EUROPEAN TYPHUS BY THE INTRA-ABDOMINAL ROUTE.

A fatal infection of irradiated white mice with the Breinl strain of European typhus has been established and passed serially for 22 passages by the intra-abdominal route. Rickettsiae were abundant and easily demonstrable in the moribund or dead mice. The mortality of irradiated mice infected with passage material (peritoneal washings or blood) was nearly 100 per cent as contrasted to no mortality in the control mice given the same dose of x-ray (450 R) and the same volume of fluid intra-abdominally.

STUDIES ON THE MECHANISM OF RECOVERY IN PNEUMOCOCCAL PNEUMONIA : I. THE ACTION OF TYPE SPECIFIC ANTIBODY UPON THE PULMONARY LESION OF EXPERIMENTAL PNEUMONIA.

A uniformly fatal lobar pneumonia was produced in white rats by inoculation of the left main bronchus with virulent Type I pneumococci suspended in mucin. All of the animals succumbed in less than 5 days, half of them dying within 48 hours. In only 5 of 40 rats was the lesion confined to the left lung, and all but one developed pleurisy, pericarditis, or both.

THE PROLONGED COEXISTENCE OF VACCINIA VIRUS IN HIGH TITRE AND LIVING CELLS IN ROLLER TUBE CULTURES OF CHICK EMBRYONIC TISSUES.

1. The virus of vaccinia in so called roller tube cultures of mixed embryonic chick tissue rapidly increases to maximal titre. 2.