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15N and 13C NMR experiments were applied to conduct a comparative study of a cold shock protein (Csp) in two states - lyophilized powder and a protein embedded in a glassy trehalose matrix. Both samples were studied at various levels of rehydration. The experiments used (measuring relaxation rates R 1 and R 1ρ, motionally averaged dipolar couplings and solid state exchange method detecting reorientation of the chemical shift anisotropy tensor) allow obtaining abundant information on the protein structural features and internal motions in a range of correlation times from nanoseconds to seconds. The main results are: (a) the trehalose coating makes the protein structure more native in comparison with the dehydrated lyophilized powder, however, trehalose still cannot remove all non-native hydrogen bonds which are present in a dehydrated protein; (b) trehalose has an appreciable effect on the internal dynamics: the motion of the backbone N-H groups in the nanosecond and microsecond time scales becomes slower while the motional amplitude remains constant; (c) upon adding water to the Csp-trehalose mixture, water molecules accumulate around proteins forming a layer between the protein surface and the trehalose matrix. The protein dynamics become faster, however, not as fast as in the fully hydrated state; (d) the hydration response of dynamics of the NH and CH(CH 2) groups in a protein is qualitatively different: upon increasing protein hydration, the correlation times of the N-H motions become shorter and the amplitude remains stable, and for CH(CH 2) groups the motional amplitude increases and the correlation times do not change. This can be explained by a different ability of the NH and CH(CH 2) groups to form hydrogen bonds. © the Owner Societies 2012.

Mechanical ventilation of newborn infants has been employed in many centers. Because methods for selection of infants and technique and pattern of ventilation have varied, comparisons of results are difficult. This report reviews the history of mechanical ventilation of the neonate and describes a scoring system developed for the selection of newborn infants for intermittent positive-pressure ventilation (IPPV/I). The clinical diagnosis and management of 204 neonates prior to selection for mechanical ventilation are outlined. All infants were hypercapnic, hypoxie, acidotic and/or apneic prior to initiation of IPP/I. Survival of these infants following mechanical ventilation is discussed in relation to the scoring system used for selection for mechanical ventilation.

• Ultrasound and computerized tomographic (CT) methods were used in detecting hydrocephalus and intraventricular hemorrhage (IVH) in three premature infants, with excellent anatomic and pathologic correlation. Ultrasonography may offer an advantageous alternative to CT scanning in evaluating suspected IVH and/or posthemorrhagic hydrocephalus in critically ill infants.

Extract: This study reports the effect of varying specific parameters of mechanical ventilation on aortic PO2 in six infants with severe respiratory distress syndrome. Twenty-seven studies were performed during the first 168 hours of mechanical ventilation. In each study, arterial oxygen partial pressure was found to vary directly with airway pressure and inversely with respiratory rate. No correlation was found between rate and pressure, or PaO2, PaCO2, and pHa. Oxygenation of infants with severe respiratory distress syndrome can be significantly influenced by variation of specific parameters of mechanical ventilation independently of change in aortic carbon dioxide tension. Speculation: Optimal oxygenation during mechanical ventilation of infants with severe respiratory distress syndrome is dependent upon selection of the specific and appropriate pattern of ventilation.

This is a worthwhile attempt to initiate a comprehensive framework for ethical issues at life's outset as they are affected by a burgeoning technology of procreation. Leading authors cover the beginnings of life, organized in sequence: preimplantation, intrauterine , and postnatal . Following this are discussions of perinatal policy in a pluralistic society, ie, comparative anthropolitical perspectives and a discussion of the complexities of translating moral perspectives into social policy. The editorial effort rests on three strong legs—the quality of the contributors, the developmental approach to life's beginning, and the capping section on policy formulation. The "Baby M" case, which pitted interests of the surrogate mother against those of gamete donor and contracting parents, has made familiar the conflicts between the interests of various sorts of "parents." Less discussed are ethical implications in creating multiple embryos. The fact that termination of pregnancy is the preponderantly available intervention after fetal genetic diagnosis is

Hypoxia secondary to apnea has been suggested as one cause of neurological abnormalities in surviving premature infants. If hypoxia is, in part, responsible for brain damage, prevention by a simple and reliable means would be important. Using an impedance plethysmograph incorporating an alarm system the respiratory patterns of 15 normal premature infants and 7 infants recovering from the respiratory distress syndrome (RDS) weighing 862–2552 gm have been continuously monitred for 5–16 days. In 7 infants we obtained simultaneous ECG tracings. The duration of apneic periods >30 s, ECG changes, and arterial blood gases were measured and the appearance of the infant and the nature of the stimulus required to re-initiate respiration was recorded. A total of 217 apneic periods of > 30 s were observed in the 22 infants. 6 infants (3 with healing RDS) had > 10 apneic episodes. Apneic periods began at end expiration and were rare in infants weighing > 1750 g. More frequent apneic periods at higher incubator temperatures were sometimes noted. When simultaneous ECG tracings were obtained marked cardiac slowing was noted within 10–15 s of the onset of apnea. Bradycardia ( 30 s) was associated with suggestive evidence of hypoxia (loss of muscle tone, cyanosis and mottling) whereas apnea of < 20 s duration was not. This study suggests apnea is more frequent than previously noted and is poorly tolerated after 20 s. Utilizing an apnea alarm, hypoxia with resultant brain damage may be prevented. (SPR)