The phospholipid composition of the cell membrane influences the spatial and temporal biochemistry of cells. We studied molecular mechanisms connecting membrane composition to cell morphology in the model bacterium Rhodobacter sphaeroides. The peptidoglycan (PG) layer of the cell wall is a dominant component of cell mechanical properties; consequently, it has been an important antibiotic target. We found that the anionic phospholipid cardiolipin (CL) plays a role in determination of the shape of R. sphaeroides cells by affecting PG precursor biosynthesis. Removing CL in R. sphaeroides alters cell morphology and increases its sensitivity to antibiotics targeting proteins synthesizing PG. These studies provide a connection to spatial biochemical control in mitochondria, which contain an inner membrane with topological features in common with R. sphaeroides.

Between January 1965 and August 1977, 122 patients with 135 arterial emboli were treated on the Peripheral Vascular Service at the Ohio State University Hospital. The heart was the source of the embolus in 94 patients (77%), one-third of whom had experienced a myocardial infarct. Thirteen patients died after the operation, which in 102 patients (84%) consisted of embolectomy only, making the hospital mortality 10.6%. Fourteen patients (11.5%) required subsequent amputations during the same hospitalization or on a later admission. The corrected limb salvage rate of 80.9% was unrelated to the length of delay in presentation. Although only 70 patients (57.4%) had palpable distal pulses following operation, 89 (73%) had a functional limb at the time of discharge or on later follow-up. An aggressive approach to the patient with an arterial embolus, regardless of the duration of symptoms, is urged. Embolectomy under local anesthesia is advocated in all cases after prompt correction of fluid and electrolyte imbalance and stabilization of the underlying cardiac disorder, except in patients with frank gangrene and irreversible rigor. In the absence of distal pulses or obvious revascularization, an intraoperative arteriogram is mandatory.

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