Ileocecectomy is definitive treatment for advanced appendicitis

Although appendectomy is the most commonly performed emergency operation septic complications of appendectomy remain a major source of morbidity. Historically, advanced appendicitis has been treated by appendectomy with cecostomy and/or drainage tubes. Our objective was to evaluate the use of ileocecal resection for the immediate treatment of advanced appendicitis. We examined the cases of all patients undergoing ileocecal resection for appendicitis from August 1989 through April 2000. There were 92 patients (60 male and 32 female) with a median age of 34 (range 6-71). Abdominal pain was present in 98 per cent of patients with duration of 5.1+/-0.6 days. Right lower quadrant tenderness was present in 91 per cent with accompanying right lower quadrant mass in 30 per cent. Temperature on admission was 38.0+/-0.1 degrees C with a white blood cell count of 15,300+/-500. Preoperative radiological studies included abdominal X-rays (33), contrast enemas (two), CT scans (41), and abdominal ultrasound (17); these studies yielded a correct preoperative diagnosis in 89 per cent. Previous appendectomy had been performed in six patients with failed percutaneous drainage of intra-abdominal abscesses in five. There were 94 cecal resections performed in 92 patients. The extent of surgical resection varied between patients and ranged from partial cecectomy (34) to ileocecectomy (55) to ileocecectomy with diverting ileostomy (five). Intra-abdominal abscesses were present at operation in 46 cases (50%), and drains were placed in 38 (41%). Skin incisions were packed open in most cases (65); there was skin closure in 27. There was no mortality encountered in this period. There were 25 complications in 23 patients (25%). Complications included postoperative abscess (10; 11%), wound infection (10; 11%), partial small bowel obstruction (two) and pulmonary embolus (one). Reoperation was required in seven patients and CT-guided percutaneous drainage in five patients. Anastomic leaks occurred in two cases of partial cecectomy and required conversion to ileocecectomy. Mean hospital stay was 10.5+/-1.0 days with adjusted hospital costs of $31,689+/-3018. We conclude that definitive treatment of advanced appendicitis can be performed by resection of the involved areas of the ileocecum. This can be accomplished with a primary anastomosis obviating the need for ileostomy and secondary operation. This aggressive surgical approach may reduce infectious complications and reduce hospital costs.

Surgical diverticulitis: treatment options

Acute diverticulitis requiring surgical intervention has conventionally been treated by resection with colostomy or delayed resection with primary anastomosis at a second admission. Our objective was to determine the outcome for treatment of diverticulitis with resection and primary anastomosis during the same hospitalization. We conducted a retrospective review of patients (n = 74) undergoing surgery for diverticulitis. Groups included: 1) resection with primary anastomosis (n = 33), 2) resection with colostomy followed by a takedown colostomy (n = 32), and 3) delayed resection with primary anastomosis at a second admission (n = 9). Despite local perforation primary anastomosis was often performed unless patients were clinically unstable or had fecal contamination. The operation was urgent in five (15%) patients in Group 1 as compared with 26 patients (88%) in Group 2. Serious intra-abdominal complications occurred in two patients (6%) in Group 1 as compared with nine patients (28%) in Group 2 and one patient (11%) in Group 3. Postoperative abscesses occurred in two patients in Group 1, five patients in Group 2, and one patient in Group 3. We have shown that resection with primary anastomosis for acute diverticulitis--even in selected patients requiring urgent operation--can be safely performed during the same hospital admission with a low complication rate.

Identification of optimal lung volume during high-frequency oscillatory ventilation using respiratory inductive plethysmography

OBJECTIVES

First, to define the relationships between critical opening and closing pressures and oxygenating efficiency, and second, to address whether respiratory inductive plethysmography (RIP) could be used to monitor changes in thoracic volume that follow changes in mean airway pressure during high- frequency oscillatory ventilation (HFOV).

DESIGN

Prospective, interventional animal study.

SETTING

University research laboratory.

SUBJECTS

Five anesthetized, paralyzed, and ventilated pigs.

INTERVENTIONS

The animals were ventilated by using HFOV after lung injury. Pre- and post-HFOV pressure-volume curves were obtained by supersyringe. A pressure-volume curve was constructed during HFOV as mean airway pressure was increased from 10 to 40 cm H(2)O and then weaned back down to the minimum sustainable. Hemodynamic and oxygenation data were obtained at each data point.

MEASUREMENTS AND MAIN RESULTS

RIP-derived thoracic volumes correlated with known lung volumes during supersyringe (r(2) =.78, p <.00001). During HFOV, three of five animals had an identifiable critical opening pressure of the lung, and four of five had an identifiable critical closing pressure. No consistent relationship between critical opening and critical closing pressures was observed. During the weaning phase of HFOV, a relative decrease in RIP-measured volume of >10% predicted the decrease in oxygenation associated with reaching the critical closing pressure.

CONCLUSIONS

The ability of RIP to detect optimal lung volume during the weaning of mean airway pressure may allow clinicians to more directly monitor lung volume changes during HFOV and use the lowest possible airway pressures after lung recruitment.

Bovine pericardial patch angioplasty in carotid endarterectomy

Patch angioplasty during carotid endarterectomy (CEA) has been shown to reduce the incidence of both early and late complications. Controversy continues, however, over the ideal patch material. Bovine pericardium (Vascu-Guard Biovascular Inc., Saint Paul, MN) offers an attractive alternative to other patch materials because of its handling and suturing characteristics that are similar to that of autogenous material. This study examines the perioperative and midterm results of bovine pericardial patch angioplasty during CEA. We studied 112 patients who underwent 129 CEAs with bovine pericardial patch angioplasty during an 18-month period. Data were collected regarding demographics, operative indications, perioperative complications, and the occurrence of late adverse outcomes based primarily on follow-up arterial duplex studies. Among this group there were 63 male (56%) and 49 female (44%) patients whose mean age was 71.8 +/- 9.1 years. In these patients there was the typical distribution of atherosclerotic risk factors. Seventy-four patients (66%) had symptomatic disease preoperatively and the remaining 38 patients (34%) were asymptomatic. Temporary cranial nerve palsy occurred in three patients (2%). There were no perioperative strokes, acute occlusions, bleeding episodes requiring reoperation, or deaths. The patients were followed up to 54 months postoperatively with a mean follow-up time of 41.7 +/- 4.4 months. During this period two patients (2%) developed three significant restenoses (70-99%). All required reoperation. There were no asymptomatic occlusions, infections, aneurysms, or rupture. These data demonstrate that bovine pericardial patch angioplasty during CEA is associated with a low incidence of both perioperative and midterm adverse outcomes.

A structural account of substrate and inhibitor specificity differences between two naphthol reductases

Two short chain dehydrogenase/reductases mediate naphthol reduction reactions in fungal melanin biosynthesis. An X-ray structure of 1,3,6,8-tetrahydroxynaphthalene reductase (4HNR) complexed with NADPH and pyroquilon was determined for examining substrate and inhibitor specificities that differ from those of 1,3,8-trihydroxynaphthalene reductase (3HNR). The 1.5 A resolution structure allows for comparisons with the 1.7 A resolution structure of 3HNR complexed with the same ligands. The sequences of the two proteins are 46% identical, and they have the same fold. The 30-fold lower affinity of the 4HNR-NADPH complex for pyroquilon (a commercial fungicide that targets 3HNR) in comparison to that of the 3HNR-NADPH complex can be explained by unfavorable interactions between the anionic carboxyl group of the C-terminal Ile282 of 4HNR and CH and CH(2) groups of the inhibitor that are countered by favorable inhibitor interactions with 3HNR. 1,3,8-Trihydroxynaphthalene (3HN) and 1,3,6,8-tetrahydroxynaphthalene (4HN) were modeled onto the cyclic structure of pyroquilon in the 4HNR-NADPH-pyroquilon complex to examine the 300-fold preference of the enzyme for 4HN over 3HN. The models suggest that the C-terminal carboxyl group of Ile282 has a favorable hydrogen bonding interaction with the C6 hydroxyl group of 4HN and an unfavorable interaction with the C6 CH group of 3HN. Models of 3HN and 4HN in the 3HNR active site suggest a favorable interaction of the sulfur atom of the C-terminal Met283 with the C6 CH group of 3HN and an unfavorable one with the C6 hydroxyl group of 4HN, accounting for the 4-fold difference in substrate specificities. Thus, the C-terminal residues of the two naphthol reductase are determinants of inhibitor and substrate specificities.

International connections among midwives

Women's health throughout the world is adversely affected by low status and literacy, poor nutrition, environmental toxins, violence, and other social, cultural, and economic factors. The majority of maternal deaths and disability occur in the developing nations of the world, such as Africa, where being born female is often a tragedy. The International Confederation of Midwives and the American College of Nurse-Midwives have nearly a century of commitment to making pregnancies and births safer and women's lives better. The shared vision of women as persons who are due full human rights guides the efforts of nurses and midwives in their global efforts of working with women and childbearing families and promoting health for all.

Rapid accumulation of phosphatidylinositol 4,5-bisphosphate and inositol 1,4,5-trisphosphate correlates with calcium mobilization in salt-stressed arabidopsis

The phosphoinositide phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P(2)] is a key signaling molecule in animal cells. It can be hydrolyzed to release 1,2-diacyglycerol and inositol 1,4,5-trisphosphate (IP(3)), which in animal cells lead to protein kinase C activation and cellular calcium mobilization, respectively. In addition to its critical roles in constitutive and regulated secretion of proteins, PtdIns(4,5)P(2) binds to proteins that modify cytoskeletal architecture and phospholipid constituents. Herein, we report that Arabidopsis plants grown in liquid media rapidly increase PtdIns(4,5)P(2) synthesis in response to treatment with sodium chloride, potassium chloride, and sorbitol. These results demonstrate that when challenged with salinity and osmotic stress, terrestrial plants respond differently than algae, yeasts, and animal cells that accumulate different species of phosphoinositides. We also show data demonstrating that whole-plant IP(3) levels increase significantly within 1 min of stress initiation, and that IP(3) levels continue to increase for more than 30 min during stress application. Furthermore, using the calcium indicators Fura-2 and Fluo-3 we show that root intracellular calcium concentrations increase in response to stress treatments. Taken together, these results suggest that in response to salt and osmotic stress, Arabidopsis uses a signaling pathway in which a small but significant portion of PtdIns(4,5)P(2) is hydrolyzed to IP(3). The accumulation of IP(3) occurs during a time frame similar to that observed for stress-induced calcium mobilization. These data also suggest that the majority of the PtdIns(4,5)P(2) synthesized in response to salt and osmotic stress may be utilized for cellular signaling events distinct from the canonical IP(3) signaling pathway.

Effects of ultraviolet-A exposure on ultraviolet-B-induced accumulation of specific flavonoids in Brassica napus

Many plant species are able to acclimate to changes in ultraviolet-B radiation (UVB) (290-320 nm) exposure. Due to the wide range of targets of UVB, plants have evolved diverse repair and protection mechanisms. These include increased biosynthesis of UVB screening compounds, elevated antioxidant activity and increased rates of DNA repair. We have shown previously that Brassica napus L. cv Topas plants can acclimate quite effectively to environmentally relevant increases in UVB through the accumulation of specific flavonoids in the leaf epidermis. However, B. napus was found to lose other flavonoids when plants are exposed to ultraviolet-A radiation (UVA) (320-400 nm) and/or UVB (Wilson et al. [1998] Photochem. Photobiol. 67, 547-553). In this study we demonstrate that the levels of all the extractable flavonoids in the leaves of B. napus plants are decreased in a dose-dependent manner in response to UVA exposure. Additionally, the accumulation of the extractable flavonoids was examined following a shift from photosynthetically active radiation (PAR) + UVA to PAR + UVB to assess if preexposure to UVA affected UVB-induced flavonoid accumulation. UVA preexposures were found to impede UVB-induced accumulation of some flavonoids. This down regulation was particularly evident for quercetin-3-O-sophoroside and quercetin-3-O-sophoroside-7-O-glucoside, which is interesting because quercetins have been demonstrated to be induced by UVB and correlated with UVB tolerance in some plant species. The photobiological nature of these UVA-mediated effects on flavonoid accumulation implies complex interactions between UVA and UVB responses.

Density-labelling of cell wall polysaccharides in cultured rose cells: comparison of incorporation of 2H and 13C from exogenous glucose

Labelling with stable isotopes has under-exploited potential for studies of polysaccharide endotransglycosylation in vivo. Ideally, the labelled polysaccharides should have the highest possible buoyant density. Although [13C6]glucose has previously been used as a precursor, it was unclear whether 2H would be efficiently incorporated from [2H]glucose or lost as D2O. Rose (Rosa sp.) cell-suspension cultures efficiently incorporated 13C from D-[13C6,2H7]glucose into wall polysaccharides with negligible dilution from atmospheric 12CO2. Also, approximately 70% of the 2H atoms in D-[13C6,2H7]glucose were retained during polysaccharide biosynthesis. This shows that relatively few cycles of intermediary metabolism leading to the release of D2O occurred before sugar residues were incorporated into wall polysaccharides. In agreement with these observations, isopycnic centrifugation in caesium trifluoroacetate gradients showed that the hydrated buoyant density of xyloglucan synthesised by rose cells growing on [13C6,2H7]glucose and [13C6]glucose was 3.7 and 2.6% higher, respectively, than in isotopically non-labelled cultures. Thus, [13C,2H]glucose-feeding enabled a 42% better resolution of 'heavy' from 'light' xyloglucan than [13C]glucose-feeding.

Isolation and characterization of senescence-induced cDNAs encoding deoxyhypusine synthase and eucaryotic translation initiation factor 5A from tomato

Full-length cDNA clones encoding deoxyhypusine synthase (DHS) and eucaryotic initiation factor 5A (eIF-5A) have been isolated from a cDNA expression library prepared from tomato leaves (Lycopersicon esculentum, cv. Match) exposed to environmental stress. DHS mediates the first of two enzymatic reactions that activate eIF-5A by converting a conserved lysine to the unusual amino acid, deoxyhypusine. Recombinant protein obtained by expressing tomato DHS cDNA in Escherichia coli proved capable of carrying out the deoxyhypusine synthase reaction in vitro in the presence of eIF-5A. Of particular interest is the finding that DHS mRNA and eIF-5A mRNA show a parallel increase in abundance in senescing tomato flowers, senescing tomato fruit, and environmentally stressed tomato leaves exhibiting programmed cell death. Western blot analyses indicated that DHS protein also increases at the onset of senescence. It is apparent from previous studies with yeast and mammalian cells that hypusine-modified eIF-5A facilitates the translation of a subset of mRNAs mediating cell division. The present study provides evidence for senescence-induced DHS and eIF-5A in tomato tissues that may facilitate the translation of mRNA species required for programmed cell death.

Characterization of plasma membrane domains enriched in lipid metabolites

A subpopulation of plasma membrane vesicles enriched in membrane lipid metabolites has been isolated from petals of carnation flowers and leaves of canola seedlings. This was achieved by immunopurification from a microsomal membrane preparation using region-specific antibodies raised against a recombinant polypeptide of the plasma membrane H(+)-ATPase. The properties of this subpopulation of vesicles were compared with those of purified plasma membrane isolated by partitioning in an aqueous dextran-polyethylene glycol two-phase system. The lipid composition of the immunopurified vesicles proved to be clearly distinguishable from that of phase-purified plasma membrane, indicating that they represent a unique subpopulation of plasma membrane vesicles. Specifically, the immunopurified vesicles are highly enriched in lipid metabolites, including free fatty acids, diacylglycerol, triacylglycerol and steryl and wax esters, by comparison with the phase-purified plasma membrane. These findings can be interpreted as indicating that lipid metabolites generated within the plasma membrane effectively phase-separate by moving laterally through the plane of the membrane to form discrete domains within the bilayer. It is also apparent that these domains, once formed, are released as vesicles into the cytosol, presumably by microvesiculation from the surface of the plasmalemma. Such removal may be part of normal membrane turnover.

Restructuring of wall-bound xyloglucan by transglycosylation in living plant cells

Xyloglucan endotransglycosylases (XETs) cleave and then re-join xyloglucan chains and may thus contribute to both wall-assembly and wall-loosening. The present experiments demonstrate the simultaneous occurrence in vivo of two types of interpolymeric transglycosylation: "integrational" (in which a newly secreted xyloglucan reacts with a previously wall-bound one) and "restructuring" (in which one previously wall-bound xyloglucan reacts with another). Xyloglucans synthesised by cultured rose (Rosa sp.) cells in "heavy" or "light" media (with [13C,2H]glucose or [12C,1H]glucose, respectively) had buoyant densities of 1.643 and 1.585 g ml-1, respectively, estimated by isopycnic centrifugation in caesium trifluoroacetate. To detect transglycosylation, we shifted heavy rose cells into light medium, then supplied a 2-h pulse of L-[1-3H]arabinose. Light [3H]xyloglucans were thus secreted into heavy, non-radioactive walls and chased by light, non-radioactive xyloglucans. At 2 h after the start of radiolabelling, the (neutral) [3H]xyloglucans were on average 29% heavy, indicating molecular grafting during integrational transglycosylation. The [3H]xyloglucans then gradually increased in density until, by 11 h, they were 38% heavy. This density increase suggests that restructuring transglycosylation reactions occurred between the now wall-bound [3H]xyloglucan and other (mainly older, i.e. heavy) wall-bound non-radioactive xyloglucans. Brefeldin A (BFA), which blocked xyloglucan secretion, did not prevent the increase in density of wall-bound [3H]xyloglucan (2-11 h). This confirms that restructuring transglycosylation occurred between pairs of previously wall-bound xyloglucans. After 7 d in BFA, the 3H was in hybrid xyloglucans in which on average 55% of the molecule was heavy. Exogenous xyloglucan oligosaccharides (competing acceptor substrates for XETs) did not affect integrational transglycosylation whereas they inhibited restructuring transglycosylation. Possible reasons for this difference are discussed. This is the first experimental evidence for restructuring transglycosylation in vivo. We argue that both integrational and restructuring transglycosylation can contribute to both wall-assembly and -loosening.

Fragrance volatiles of developing and senescing carnation flowers

Thirteen major volatiles of the carnation flower fragrance signature have been identified by GC/MS. Of these, ten, hexanal, (2E)-hexenal, 1-hexanol, 2-hexanol, 3-hexen-1-ol, nonanal, benzaldehyde, benzyl alcohol, benzyl benzoate and caryophyllene, were quantified. The steady-state levels of these ten volatiles change independently as the flowers develop and senesce, suggesting that their synthesis is developmentally regulated. In addition, the chemical composition of the fragrance signature in naturally senesced flowers proved to be very different from that for flowers that had been induced to senesce prematurely by treatment with ethylene. Thus, senescence-related changes in carnation floral scent appear not to be directly regulated by ethylene. From cellular fractionation studies, it is evident that all of the volatiles, except 2-hexanol, are present in both membranous and cytosolic compartments, suggesting that their synthesis is membrane-associated and that they subsequently partition into the cytosol in accordance with partition coefficients.

Optimizing intrapulmonary perfluorocarbon distribution: Fluoroscopic comparison of mode of ventilation and body position

OBJECTIVE

Partial liquid ventilation with the perfluorochemical, perflubron, has been shown to improve lung mechanics and enhance gas exchange in the treatment of severe acute lung injury. However, the most effective strategy to provide optimal intrapulmonary distribution of perflubron has not been fully accessed. The objective of this study was to examine the effect of body position (supine vs. rotational) and mode of ventilation (conventional mechanical ventilation [CMV] vs. high-frequency oscillatory ventilation [HFOV]) on perflubron distribution and oxygenation improvement.

DESIGN

Prospective, randomized, animal trial.

SETTING

Research laboratory at a university medical center.

SUBJECTS

Twenty healthy piglets (4.5-6.6 kg).

INTERVENTIONS

Subjects underwent repetitive saline lavage to achieve a uniform degree of lung injury and then were randomized to either CMV or were converted to HFOV. Within each ventilator group, animals were randomized to supine positioning (S) or rotational positioning with alternation between supine and prone position (R) during incremental dosing of three 5-mL/kg doses of perflubron.

MEASUREMENTS AND MAIN RESULTS

Arterial blood gas tensions, hemodynamic variables, and the oxygenation index were recorded after each dose of 5 mL/kg. Lateral cinefluoroscopic images after each dose were digitized for computer analysis of density. A density index was calculated for a 2-cm2 window in three dorsal and three ventral lung regions. Uniformity of distribution was calculated by comparing the mean density among the six regions. Oxygenation improvements were compared between groups. There were no significant differences in hemodynamic variables or gas exchange after lung injury in the four groups. Rotational positioning produced significantly more uniform perflubron distribution during both CMV and HFOV. This effect was independent of the mode of ventilation. The mean ventral density index was affected by rotating position and HFOV mode of ventilation after 10 mL/kg of perflubron, and rotating position was affected only after 15 mL/kg of perflubron. There was a significant reduction in the oxygenation index from baseline to end lavage in both CMV groups, as well as all of the animals that were rotated.

CONCLUSION

Perflubron is more uniformly dispersed when dosed in a rotational fashion with alternation between supine and prone position during incremental dosing. This effect is independent of mode of ventilation. There was no relationship between oxygenation improvements and nondependent perflubron distribution. CMV and rotating dosing both led to a significant decrease in the oxygenation index after a 15 mL/kg dose of perflubron. This information has important impact on the future development of dosing strategies and clinical trial design.

Porcelain gallbladder is not associated with gallbladder carcinoma

The surgical management of porcelain gallbladder is based on studies performed in 1931 and 1962, which indicated a correlation between porcelain gallbladder and carcinoma. We sought to evaluate the characteristics of patients with porcelain gallbladder and the risk for gallbladder carcinoma. The medical records of 10,741 cholecystectomies performed between 1955 and 1998 were reviewed and recorded. The pathology slides were evaluated for evidence of calcification and gallbladder carcinoma. Fifteen (0.14%) of 10,741 specimens were porcelain gallbladders. Ten patients (67%) had symptoms suggestive of biliary colic or cholecystitis. Five (33%) were asymptomatic and diagnosed incidentally. All specimens demonstrated chronic cholecystitis and partial calcification of the gallbladder wall. Nine (60%) had cholelithiasis. None had gallbladder carcinoma by recent review of pathologic material. During this same period 88 (0.82%) patients had gallbladder carcinoma, none of which showed calcification of the wall. This report represents the largest modern review of porcelain gallbladders. No carcinoma was identified among patients with porcelain gallbladder. In addition no patient with gallbladder carcinoma had calcified gallbladder. With a better understanding of the natural history of the porcelain gallbladder the current management of these patients may change.

The second naphthol reductase of fungal melanin biosynthesis in Magnaporthe grisea: tetrahydroxynaphthalene reductase

Mutants of Magnaporthe grisea harboring a defective gene for 1,3, 8-trihydroxynaphthalene reductase retain the capability to produce scytalone, thus suggesting the existence of a second naphthol reductase that can catalyze the reduction of 1,3,6, 8-tetrahydroxynaphthalene to scytalone within the fungal melanin biosynthetic pathway. The second naphthol reductase gene was cloned from M. grisea by identification of cDNA fragments with weak homology to the cDNA of trihydroxynaphthalene reductase. The amino acid sequence for the second naphthol reductase is 46% identical to that of trihydroxynaphthalene reductase. The second naphthol reductase was produced in Esherichia coli and purified to homogeneity. Substrate competition experiments indicate that the second reductase prefers tetrahydroxynaphthalene over trihydroxynaphthalene by a factor of 310; trihydroxynaphthalene reductase prefers trihydroxynaphthalene over tetrahydroxynaphthalene by a factor of 4.2. On the basis of the 1300-fold difference in substrate specificities between the two reductases, the second reductase is designated tetrahydroxynaphthalene reductase. Tetrahydroxynaphthalene reductase has a 200-fold larger K(i) for the fungicide tricyclazole than that of trihydroxynaphthalene reductase, and this accounts for the latter enzyme being the primary physiological target of the fungicide. M. grisea mutants lacking activities for both trihydroxynaphthalene and tetrahydroxynaphthalene reductases do not produce scytalone, indicating that there are no other metabolic routes to scytalone.

Inhaled nitric oxide reduces the need for extracorporeal membrane oxygenation in infants with persistent pulmonary hypertension of the newborn

OBJECTIVE

We previously reported improved oxygenation, but no change, in rates of extracorporeal membrane oxygenation (ECMO) use or death among infants with persistent pulmonary hypertension of the newborn who received inhaled nitric oxide (NO) with conventional ventilation, irrespective of lung disease. The goal of our study was to determine whether treatment with inhaled NO improves oxygenation and clinical outcomes in infants with persistent pulmonary hypertension of the newborn and associated lung disease who are ventilated with high-frequency oscillatory ventilation (HFOV).

DESIGN

Single-center, prospective, randomized, controlled trial.

SETTING

Newborn intensive care unit of a tertiary care teaching hospital.

PATIENTS

We studied infants with a gestational age of > or =34 wks who were receiving mechanical ventilatory support and had echocardiographic and clinical evidence of pulmonary hypertension and hypoxemia (PaO2 < or =100 mm Hg on FIO2 = 1.0), despite optimal medical management Infants with congenital heart disease, diaphragmatic hernia, or other major anomalies were excluded.

INTERVENTIONS

The treatment group received inhaled NO, whereas the control group did not. Adjunct therapies and ECMO criteria were the same in the two groups of patients. Investigators and clinicians were not masked as to treatment assignment, and no crossover of patients was permitted.

MEASUREMENTS AND MAIN RESULTS

Primary outcome variables were mortality and use of ECMO. Secondary outcomes included change in oxygenation and duration of mechanical ventilatory support and supplemental oxygen therapy. Forty-two patients were enrolled. Baseline oxygenation and clinical characteristics were similar in the two groups of patients. Infants in the inhaled NO group (n = 21) had improved measures of oxygenation at 15 mins and 1 hr after enrollment compared with infants in the control group (n = 20). Fewer infants in the inhaled NO group compared with the control group were treated with ECMO (14% vs. 55%, respectively; p = .007). Mortality did not differ with treatment assignment.

CONCLUSIONS

Among infants ventilated by HFOV, those receiving inhaled NO had a reduced need for ECMO. We speculate that HFOV enhances the effectiveness of inhaled NO treatment in infants with persistent pulmonary hypertension of the newborn and associated lung disease.

Co-association of cytochrome f catabolites and plastid-lipid-associated protein with chloroplast lipid particles

Distinguishable populations of lipid particles isolated from chloroplasts of yellow wax bean (Phaseolus vulgaris L. cv Kinghorn Wax) leaves have been found to contain plastid-lipid-associated protein (J. Pozueta-Romero, F. Rafia, G. Houlné, C. Cheniclet, J.P. Carde, M.-L. Schantz, R. Schantz [1997] Plant Physiol 115: 1185-1194). One population is comprised of plastoglobuli obtained from sonicated chloroplasts by flotation centrifugation. Higher density lipid-protein particles isolated from chloroplast stroma by ultrafiltration constitute a second population. Inasmuch as the stromal lipid-protein particles contain plastid-lipid-associated protein, but are distinguishable from plastoglobuli in terms of their lipid and protein composition, they appear to be plastoglobuli-like particles. Of particular interest is the finding that plastoglobuli and the higher density lipid-protein particles both contain catabolites of the thylakoid protein, cytochrome f. These observations support the view that there are distinguishable populations of plastoglobuli-like particles in chloroplasts. They further suggest that the formation of these particles may allow removal of protein catabolites from the thylakoid membrane that are destined for degradation as part of normal thylakoid turnover.

Prospective evaluation of early versus delayed laparoscopic cholecystectomy for treatment of acute cholecystitis

Although laparoscopic cholecystectomy (LC) is known to be safe in the treatment of acute cholecystitis (AC), the optimal timing of laparoscopic intervention remains controversial. The objective of this study is to prospectively compare the safety and cost effectiveness of early versus delayed LC in AC. Our study population consisted of 43 patients presenting with AC (localized tenderness, white blood cell count >10.0 or temperature >38.0 degrees C, and ultrasound confirmation) who were prospectively randomized to early versus delayed LC during their first admission. Exclusion criteria included a history of peptic ulcer disease or evidence of gallbladder perforation. All patients were treated with bowel rest and antibiotics (piperacillin 2 g intravenous piggyback every 6 hours). Early treatment patients underwent LC as soon as the operating schedule allowed. Delayed treatment patients received anti-inflammatory medication (indomethacin 50 mg per rectum every 12 hours) in addition to bowel rest and antibiotics and underwent operation after resolution of symptoms or within 5 days if symptoms failed to resolve. Early LC was performed in 21 patients, whereas 22 patients underwent delayed LC. There was no difference in age, temperature, or white blood cell count on admission between groups. Early LC slightly reduced operative time and conversion rate. There was no difference in complications. Estimated blood loss was significantly lower in those receiving early LC. There was also a significant reduction in total hospital stay and hospital charges with early LC. We conclude that delay in operation combined with anti-inflammatory medication showed no advantage with regard to operative time, conversion, or complication rate. Furthermore, early laparoscopic intervention significantly reduced operative blood loss, hospital days, and hospital charges.