Ureaplasma urealyticum and chronic lung disease in very low birth weight infants during the exogenous surfactant era.

BACKGROUND: An association between recovery of Ureaplasma urealyticum from the respiratory tract of very low birth weight (VLBW) infants (< or =1500 g) and later chronic lung disease (CLD) was reported by several authors before the routine use of exogenous surfactant (SURF). We sought to assess whether this relation persists in the era of routine SURF. METHODS: We prospectively studied a cohort of 105 VLBW infants who required mechanical ventilation at < 12 h of age. Tracheal aspirates for U. urealyticum culture were obtained before administration of SURF or antibiotics. Clinicians were unaware of U. urealyticum status. Chest radiographs at 28 days were reviewed by a single pediatric radiologist, blinded to U. urealyticum status. Sample size was predetermined to detect a 30% increase in CLD among those with U. urealyticum recovery from tracheal culture (U. urealyticum-positive) with alpha <0.05 and beta <0.20. RESULTS: Of the study infants 22 were U. urealyticum-positive and 83 were U. urealyticum-negative. No differences were found between the groups for birth weight, gestational age, gender, inborn, antenatal or postnatal steroid use, SURF therapy, non-U. urealyticum infection, necrotizing enterocolitis, patent ductus arteriosus, intraventricular hemorrhage or cystic periventricular leukomalacia. At 28 days U. urealyticum-positive patients were significantly more likely to have CLD than U. urealyticum-negative [15 of 22 (68%) vs. 30 of 83 (36%); P < 0.02]. The U. urealyticum-positive patients also required significantly longer courses of supplemental oxygen and mechanical ventilation. No significant differences were found for CLD at 36 weeks postconception or duration of hospitalization, although type II error could not be excluded for these secondary endpoints. CONCLUSIONS: Respiratory U. urealyticum at or shortly after birth remains associated with CLD at 28 days despite routine use of SURF. Controlled trials of anti-Ureaplasma therapy in U. urealyticum-positive VLBWs as soon after birth as possible may determine whether CLD, duration of respiratory support and attendant costs can be decreased.

Neutral points in an atmosphere-ocean system. 1: Upwelling light field.

We have developed a Monte Carlo code that utilizes the complete Stokes vector to examine the structure of the degree of linear polarization in the complete observable solid angle at any level in an atmosphere-ocean system. By performing these calculations we are able to compute the positions of neutral points in the upwelling light above and beneath the ocean surface. The locations of these points in a single-scatter calculation and a Monte Carlo treatment are shown for various conditions. The presence of aerosols in the atmosphere and hydrosols in the ocean was found to have an effect on the location of these neutral points.

Streptococcus mitis infection in newborns.

Although neonatal infections caused by Streptococcus viridans have been suggested to be less severe than those caused by classic neonatal pathogens, little is known about neonatal infections caused by specific species within this group of bacteria. We report six infants who had S. mitis isolated from blood culture. All were infected at < or = 3 days of age; five of the mothers had perinatal risk factors for neonatal sepsis. Five infants were preterm and three had birth weights < or = 2500 gm. Hematologic abnormalities were common. Two died as a result of the infection. Antibiotic susceptibility testing of four isolates revealed resistance to penicillin and ampicillin in three and resistance to gentamicin in two. In vivo resistance was not observed. S. mitis is not part of normal skin flora, should not be assumed to be a contaminant, and can cause severe neonatal disease. If S. mitis or S. viridans are recovered from a normally sterile body site and the patient fails to improve with penicillin therapy, it seems prudent to switch to vancomycin until susceptibility results are available.

Association of isoimmune thrombocytopenia and neonatal hyperinsulinism/hypoglycemia.

Neonatal hyperinsulinism and hypoglycemia have a well-established association with maternal Rh isoimmunization. We report herein an infant who presented with significant neonatal hypoglycemia that was found to be secondary to hyperinsulinism and who also had thrombocytopenia secondary to maternal platelet isoimmunization.

Gastric "pseudolymphoma" with restricted light chain expression in a patient with obscure gastrointestinal blood loss.

We present a case report of a gastric "pseudolymphoma" (GL) that exhibits restricted light chain expression and, therefore, illustrates the dilemma encountered when histologically benign lesions have phenotypic abnormalities suggesting malignancy. For many years this lesion has been considered usually benign; however, recent reports such as this one demonstrate immunologic signs of monoclonality in an otherwise histologically benign lesion. This finding challenges our assumptions as to the nature of this lesion and our definition of cancer. The lesion also displays "Castleman-like" features (angiofollicular hyperplasia) as well as "common inflammatory" germinal centers. In addition we briefly review the literature.

Synthesis and characterization of an affinity label for brain receptors to psychotomimetic benzomorphans: differentiation of sigma-type and phencyclidine receptors.

Brain sigma-type receptors and phencyclidine receptors are thought to mediate the psychotomimetic effects of benzomorphans and phencyclidine in humans. Recently, we reported the characterization of a selective sigma receptor ligand, 1,3-di-o-tolyl-guanidine (DTG), that shows negligible crossreactivity with phencyclidine receptors. Here we describe the synthesis and characterization of an isothiocyanate derivative of DTG, di-o-tolyl-guanidine-isothiocyanate (DIGIT). Guinea pig brain membranes treated with nanomolar doses of DIGIT followed by extensive washing exhibit a dose dependent reduction of [3H]DTG and (+)[3H]3-(3-hydroxyphenyl)-N-(1-propyl)piperidine [+)[3H]3-PPP) binding to sigma receptors. Binding of radiolabelled ligands for phencyclidine, mu-opioid, benzodiazepine and dopamine-D2 receptors is not affected by membrane treatment with DIGIT, indicating specificity of the affinity label for sigma-type receptors. Treatment of DIGIT-derivatized membranes with 2 M NaCl does not result in recovery of sigma binding activity, suggesting that DIGIT's interaction with sigma receptors is not of an ionic nature. Equilibrium saturation binding experiments show that the inhibition of [3H]DTG binding to sigma receptors by DIGIT pretreatment of membranes is attributable to an irreversible reduction in the affinity (increase in Kd) of sigma receptors for DTG. The finding that sigma receptors are irreversibly modified by DIGIT whereas phencyclidine receptors are not affected suggests that sigma receptors are physically separate from phencyclidine receptors. The availability of a selective affinity label for the sigma receptor should facilitate the purification of the receptors and the characterization of sigma-type pharmacological effects in vivo and in vitro.

Acute acalculous cholecystitis complicating abdominal aortic aneurysm resection.

Acute acalculous cholecystitis developed in six patients recovering from repair of an abdominal aortic aneurysm. All patients were men with significant concurrent medical illnesses, and three patients had undergone operation for a ruptured aneurysm. Symptoms appeared at a mean of 3 weeks postoperatively and consisted of right upper quadrant pain, fever, leukocytosis, and slight elevation of liver function test results. Treatment consisted of cholecystostomy (three patients) or cholecystectomy (three patients), with an overall mortality rate of 50%. When cholecystitis is suspected after aortic aneurysm repair, early confirmation of the diagnosis should be obtained with ultrasound or a technetium hepatobiliary scan and cholecystostomy or cholecystectomy undertaken if the patient does not rapidly improve with medical management.

Adenocarcinoma of the small intestine.

Sixty-five patients with adenocarcinoma of the small intestine were encountered over a 31 year period. The duodenum was the most common location, with a decreasing frequency distally. Associated malignancies were present in a fourth of the patients. Presenting signs and symptoms were vague and related to either obstruction or bleeding. Barium contrast examination and endoscopy for duodenal tumors were the primary diagnostic modalities. Curative treatment was wide resection of bowel and mesentery for jejunal and ileal tumors and pancreaticoduodenectomy for duodenal tumors. Favorable prognosticators included jejunal location, absence of nodal metastases, and a well-differentiated grade. Stage for stage, the prognosis of patients with adenocarcinoma of the small intestine parallels that of patients with adenocarcinoma of the colon. With greater awareness of this tumor, it is possible that earlier detection will lead to improved overall survival.

Management of cholelithiasis in patients with abdominal aortic aneurysm.

Gallstones were detected in 42 of 865 patients with abdominal aortic aneurysm (4.9%). Eighteen patients underwent concomitant aneurysm resection and cholecystectomy. Eleven patients had aneurysmectomy without cholecystectomy. Thirteen patients underwent cholecystectomy alone. There were no significant increases in operative mortality, duration of operation, or length of hospital stay when cholecystectomy was added to aneurysm resection. However, there was one instance of prosthetic infection which occurred in a patient who did not have his graft retroperitonealized prior to cholecystectomy, and who also underwent gastrostomy and drainage of the liver bed. There have been no graft complications in the remaining 17 consecutive patients who had their graft retroperitonealized prior to cholecystectomy. Nine of 11 patients who underwent aneurysmectomy without cholecystectomy experienced an episode of acute cholecystitis during a mean follow-up period of 2.9 years. Two of these episodes occurred in the immediate postoperative period and one patient died of biliary sepsis. On the basis of these findings, concomitant aneurysmectomy and cholecystectomy is advised in those patients with cholelithiasis undergoing aortic aneurysm resection providing no contraindications exist.

Improved arterial portography in portal hypertension during reactive mesenteric hyperemia induced by preceding 2-minute balloon occlusion of the superior mesenteric artery.

The value of performing arterial portography during reactive hyperemia was investigated in four dogs with presinusoidal cirrhosis, stable portal hypertension in excess of 20 cm of water, and extensive porto-systemic venous collaterals, and compared to tolazoline (1 mg/kg) and control studies. With SMA balloon occlusion the maximum decrease in portal flow and pressure occurred between 1 and 2 minutes. During reactive hyperemia following immediately the release of a 2-minute SMA occlusion, portal flow and pressure increased from pre-occlusion values (mean +/- 1 SE, n:4) of 15 +/- 2 ml per min per kg and 25 +/- 1 cm H2O to 32 +/- 5 ml per kg and 40 +/- 2 cm H2O. With reactive hyperemia both significant higher peak iodine concentrations in the portal blood and significant improvement in visualization of the portal system and porto-systemic venous collaterals occurred when compared to tolazoline or control angiograms. With reactive hyperemia both peak blood iodine concentrations and maximum opacification of the portal vein occur 2 to 3 and 4 to 6 seconds earlier than with tolazoline or in controls, respectively. Compared to controls, tolazoline increased peak iodine concentrations in portal vein significantly and improved visualization of the portal system and collaterals in 7 of 12 examinations. Judged from the experience in peripheral arteriography, performance of angiography during reactive hyperemia appears to be a very safe procedure. However, the use of balloon catheters carries additional risks particularly when not properly used.

Vascularity of gastrointestinal staple lines demonstrated with silicone rubber injection.

Gastrointestinal stapling devices were applied across canine small intestine, and then the blood supply of the stapled segments was immediately filled with silicone rubber. After tissue clearing and microdissection, the outstanding vascularity of the staple lines was clearly demonstrated. The B configuration of the closed staple allows blood vessels of substantial size to pass through it. This might make staple technique especially advantageous whenever vascularity is critical.

Carcinoma of the extrahepatic bile ducts.

The records of patients with carcinoma of the extrahepatic bile ducts, including the ampulla of Vater, operated on at the University of Rochester Medical Center between 1960 and 1980 were reviewed. All 47 patients had similar manifestations and laboratory findings; percutaneous transhepatic cholangiography and endoscopic retrograde cholangiopancreatography were the two studies that consistently localized the tumor. Seven of eight patients with carcinoma of the ampulla underwent pancreaticoduodenectomy. At this writing five are alive and well without evidence of recurrence (a mean of 47 months). Twenty-three tumors were located at or proximal to the confluence of the right and left hepatic ducts; 16 were distal to this point. The six patients with distal lesions that were resected had a mean survival time of 14 months; the mean survival time was 7 months for the six patients in whom the operation was restricted to drainage of the proximal duct. Of the group of patients subjected to exploratory surgery and biopsy only, none survived longer than a month. Resection was carried out in only one patient for a proximal lesion; this patient died 28 months after the operation. Patients with proximal lesions who underwent drainage procedures lived an average of 7.6 months. In all groups several was longer in patients without metastases at the time of operation. The survival time after the resection was significantly longer than that associated with drainage, which suggests a more aggressive approach to these lesions.

Corrosive jejunitis due to ingestion of nitric acid.

Corrosive damage to the small bowel is not common; stasis of acid in the stomach usually prevents extensive jejunal damage. The case presented herein is unusual because the patient had a gastroenterostomy and sustained extensive injury of the jejunum after ingesting acid. The patient survived but developed a jejunal stricture that eventually required resection.

Effect of sphincteroplasty on gallbladder function and bile composition.

The effect of sphincteroplasty on bile concentration and composition and on gallbladder function was investigated in the dog. Gallbladder and hepatic bile samples were analyzed for cholesterol, phospholipid (lecithin), bile salt concentration and individual bile salt content. Motor function was studied by cholecystokinin-cholecystography with changes in gallbladder volume computed from the radiographs. All bile samples were cultured and at the conclusion of the experiments, the gallbladders were histologically examined. Sphincteroplasty did not alter biliary cholesterol concentration but the concentration of lecithin and bile salts decreased in gallbladder bile and increased in hepatic bile (p less than .001). These changes depict a trend toward greater lithogenicity for gallbladder bile and lesser lithogenicity for hepatic bile. Postoperative analysis of individual bile salts in gallbladder bile showed an increase in monohydroxy and dihydroxy bile salts and a decrease in trihydroxy bile salts (p less than .001). This tendency has been shown to be conducive to gallstone formation. The concentrating ability of the gallbladder was partially eliminated by sphincteroplasty but gallbladder filling and motor response to stimulation by cholecystokinin was not affected. All gallbladders demonstrated histologic changes of chronic inflammation and all developed a significant bacterial flora following sphincteroplasty. It is concluded that cholecystectomy should always be performed following transduodenal sphincteroplasty not because of any resultant abnormality of motor function, as has previously been held, but because of the resultant abnormality of gallbladder pathophysiology.

Evaluation of Raw Milk Quality Tests.

A study was done to evaluate raw milk quality tests in an attempt to answer some questions regarding values or standards by which milk acceptance is determined. Initially, of 315 individual producer samples, 226 (72%) had proteolytic psychrotrophs. More than 90% of these psychrotrophs were of the genus Pseudomonas . All samples were obtained from four dairy companies processing milk in Georgia. One dairy had individual producers whose milk samples contained a large percentage of thermoduric psychrotrophs. "Bitter" flavors were more prevalent in samples collected from this dairy than in samples from the other three dairies. The degree of measurable proteolysis (Hull value) was directly correlated with the incidence of the naturally occurring "bitter" flavor. The mean Hull value for milk from this dairy (30.62 µg/ml) was 12-14 µg higher than the other three means. The mean Hull value for the "bitter" samples was 46 µg/ml.

Diagnostic laparotomy for fever or abdominal pain of unknown origin.

Diagnostic laparotomy performed on twenty-four patients with FUO and twenty-seven patients with obscure abdominal pain resulted in a positive yield of 87 and 82 per cent, respectively. No deaths occurred in either group and the complication rate was minimal. These findings indicate that it is appropriate to include laparotomy in the armamentarium for diagnosis of the cause of FUO and abdominal pain.