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Biomedical subjects

J C Langer

Publications and source records attributed to J C Langer.

At least 109 records · Page 6Linked to original sources

Umbilical fold incision for pyloromyotomy.

A 5-year experience with 100 infants undergoing pyloromyotomy was reviewed. Fifty infants who had a standard right upper quadrant incision were compared with 50 infants in whom an umbilical fold incision was used. The groups did not differ significantly with respect to length of operating time, hospital stay, or intraoperative complications. Wound complications were infrequent and minor in both groups. The umbilical fold incision permits excellent access to the pylorus, while leaving an almost undetectable scar.

Female↗

Etiology of intestinal damage in gastroschisis, II. Timing and reversibility of histological changes, mucosal function, and contractility.

Previous work in the fetal lamb examined the relative effects of amniotic fluid and bowel constriction in the etiology of bowel damage in gastroschisis. The present study used the same model to assess the timing and reversibility of these changes during gestation. Gastroschisis was created at 80 days' gestation, and a tape was placed around the bowel to cause gradual constriction with growth. Lambs were killed at 100 days, 120 days, and term. Bowel damage was assessed using histology, mucosal enzyme activity, and in vitro motility. In an additional "repaired" group, the constrictor was removed at 120 days, a silastic pouch placed over the bowel, and bowel damage assessed at term. Normal fetuses at each gestational age were used as controls. A fibrous peel was observed at all gestational ages. Mucosal villous atrophy and mesenteric venous and lymphatic dilation were mild at 100 and 120 days, but severe at term. These changes were present but mild in repaired animals at term. Mucosal enzyme activity decreased gradually with gestational age; inhibition of maltase activity was maximal at term, and was significantly reversed by repair, whereas inhibition of aminooligopeptidase activity was maximal at 120 days, and was not affected by repair. Protein/DNA, DNA/weight, and protein/weight ratios showed that repaired mucosal cells were significantly more proliferative, smaller, and less mature than control or gastroschisis cells. In vitro motility studies demonstrated a mild decrease in contractility at 100 and 120 days, and a large decrease at term. This deleterious effect at the end of gestation was only partially reversed by repair in utero.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Muscles↗

Correction of congenital diaphragmatic hernia in utero, V. Initial clinical experience.

Review of our experience with 45 cases of prenatally diagnosed congenital diaphragmatic hernia (CDH) confirms that most fetuses (77%) will not survive despite optimal pre- and postnatal care. Polyhydramnios, associated anomalies, early diagnosis, and a large volume of herniated viscera (including liver) are associated with a particularly dismal prognosis. After extensive experimental work demonstrated the efficacy, feasibility, and safety of repair in utero, we attempted to salvage six highly selected fetuses with severe CDH by open fetal surgery. Five had liver incarcerated in the chest: three died at operation because attempts to reduce the liver compromised umbilical venous return. In one, a Goretex diaphragm was constructed around the liver, but the baby died after birth. The last two fetuses, one with incarcerated liver, were successfully repaired. Both demonstrated rapid growth of the lung in utero, had surprisingly good lung function after birth despite prematurity, had the abdominal patch removed at 2 weeks, and subsequently died of nonpulmonary problems (an unrelated nursery accident in one and intestinal complications in the other). The only maternal complication was amniotic fluid leak and preterm labor. All six women are well and four have had subsequent normal children. From this phase I experience, we conclude that fetal surgery appears safe for the mother and her reproductive potential, that fetal CDH repair is feasible in selected cases, and that the fetal lung responds quickly after decompression. However, fetal repair remains a formidable technical challenge.

Adolescent↗

Cervical cystic hygroma in the fetus: clinical spectrum and outcome.

Cervical cystic hygroma is thought by most pediatric surgeons to be an isolated, usually resectable lesion with an excellent prognosis. However, prenatal sonography has revealed a high "hidden mortality" among fetuses with this condition, and most perinatologists consider it to be uniformly fatal. In an attempt to resolve these two differing perspectives, we analyzed 29 cases seen at two centers over 4 years. Of 27 fetuses diagnosed before 30 weeks' gestation, only one survived. Twenty-five of the 27 were aborted; severe hydrops was present in 21 of these 25. Two of the 27, both with stigmata of Noonan's syndrome, underwent spontaneous regression during the second trimester: one died at 2 weeks of age, and the other survived. Successful karyotypes were obtained on 17 fetuses: nine were normal, seven were 45X, and one was trisomy 21. Fetuses with abnormal karyotypes had a lower incidence of polyhydramnios (0% v 67%), additional anomalies (12% v 67%), and consanguinity or a history of abnormal pregnancies (0% v 89%). Two fetuses were diagnosed after 30 weeks' gestation. Neither had hydrops, polyhydramnios, associated anomalies, or an abnormal karyotype. One had a completely normal sonogram at 17 weeks' gestation. Both were operated on within the first 4 days of life; one did well without complications, and the other required a permanent tracheostomy because of extensive hypopharyngeal involvement. A cystic hygroma presenting in the fetus has a different natural history and prognosis from one presenting postnatally. The vast majority of fetal cases are diagnosed before 30 weeks' gestation, and present with hydrops or diffuse lymphangiomatosis. The dismal outlook in this group justifies elective termination in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Studies in fetal wound healing, VI. Second and early third trimester fetal wounds demonstrate rapid collagen deposition without scar formation.

The mechanisms that underlie the lack of scarring in fetal wounds are unknown, but probably relate to the control of collagen fibrillogenesis. The role of collagen in the fetal wound matrix is controversial, and several wound implant models have been used to evaluate collagen deposition in fetal wounds. Unfortunately, these models create an artificial wound environment and may thereby affect the results. In order to study fetal wound collagen deposition in linear wounds without artificially altering the wound environment, we applied a highly sensitive immunohistochemical technique that uses antibodies to collagen types I, III, IV, and VI. We found that collagen was deposited in fetal wounds much more rapidly than in adult wounds. Wound collagen deposition occurred in a normal dermal and mesenchymal pattern in second and early third trimester fetal lambs. These findings are consistent with the observation that the fetus heals rapidly and without scar formation. In contrast, wounds in late gestation fetal lambs showed some evidence of scar formation. Further studies may suggest ways to alter the adult wound so that it heals in a fetal manner.

Animals↗

Gastrointestinal tract obstruction in the fetus.

Surgical advice is often sought when a prenatal diagnosis of gastrointestinal tract obstruction is made. We reviewed our experience with 17 such cases during a 4-year period. Eight fetuses had complete proximal obstruction. Seven of the 8 did well after maternal transport to a perinatal center and prompt neonatal surgery. Six fetuses had distal obstruction with dilated bowel and increased peristalsis. Two died after birth (1 with severe associated anomalies and 1 with short-bowel syndrome), and the other 4 did well. Three fetuses had a false-positive diagnosis of in utero meconium peritonitis. Two died and the other had no postnatal evidence of obstruction. Our data suggest (1) polyhydramnios may not be present early in gestation or with distal obstruction; (2) other anomalies, including a family history of cystic fibrosis, should be sought; (3) dilated bowel with increased peristalsis is diagnostic of fetal gastrointestinal tract obstruction, whereas intra-abdominal calcification and ascites are nonspecific findings; (4) late development of ascites in a fetus with documented obstruction may be an indication for early delivery; and (5) prenatal diagnosis permits appropriate counseling, planned delivery, and prompt postnatal resuscitation and surgery with a good prognosis in most cases.

Abnormalities, Multiple↗

Fetal hydrops and death from sacrococcygeal teratoma: rationale for fetal surgery.

Most sacrococcygeal teratomas diagnosed before birth can be managed by planned delivery and postnatal surgery. However, large tumors early in gestation may result in placentomegaly, hydrops, and fetal death and a preeclampsia-like syndrome in the mother. This chain of events may result from high output cardiac failure in the fetus caused by arteriovenous shunting through the tumor. We recently encountered this situation in a fetus at 21 weeks' gestation and performed fetal surgery in an attempt to reverse the process. Excision of the teratoma resulted in reversal of hydrops, diminution of descending aortic flow on Doppler echocardiography, and decrease in placental thickness. Despite these changes, uterine irritability after hysterotomy resulted in labor and delivery of a nonviable premature infant. This case demonstrates that when fetal sacrococcygeal teratoma becomes very large early in gestation, high output cardiac failure can endanger both fetus and mother. In the future, use of Doppler echocardiography may allow appropriate selection of high-risk fetuses. Intervention to prevent arteriovenous shunting through the tumor may offer these fetuses an improved chance for survival.

Adult↗

Systemic-to-pulmonary artery shunt using the internal mammary artery.

Systemic-to-pulmonary artery shunts may be useful for palliation of cyanotic congenital heart disease. We report the case of a 5-year-old boy in whom the internal mammary artery was used to create a systemic-to-pulmonary artery shunt after failure of a previous Blalock-Taussig shunt. This technique may have distinct advantages in selected cases and should be considered as an alternative during investigation of the older child who requires a systemic-to-pulmonary artery shunt.

Anastomosis, Surgical↗

Etiology of intestinal damage in gastroschisis. I: Effects of amniotic fluid exposure and bowel constriction in a fetal lamb model.

Gastroschisis is often complicated by damage to the herniated small bowel, resulting in motility and absorption disturbances and occasional intestinal necrosis and atresia. To study the pathophysiology of this process, a model of gastroschisis was developed in fetal lambs. At 80 days' gestation, the anterior abdominal wall was partially excised to create a small peritoneal cavity, and the small bowel was extruded through a Silastic ring to create a defect of uniform size. In one experimental group, a tie was placed around the herniated bowel at the level of the abdominal wall to provide gradual constriction as the fetus grew. In a second group, no tie was placed. Control animals had a simple laparotomy and no abdominal wall defect; some also had a constrictor placed around the base of the bowel. The animals were delivered near term, and the bowel was evaluated histologically and by an in-vitro bowel motility assay. Histologic examination showed normal ganglion cells in all groups and no evidence of ischemic injury. A fibrous peel was seen only in bowel exposed to amniotic fluid, with or without a constrictor. Lymphatic and venous dilation, smooth-muscle thickening, and focal mucosal blunting were seen in bowel subjected to chronic obstruction by a constrictor, regardless of whether it was exposed to amniotic fluid. Both constriction of the bowel and amniotic fluid exposure were associated with a decrease in motility; these two effects were independent and additive.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Muscles↗

Diagnosis and incidence of cardiac injury in children with blunt thoracic trauma.

Over a 20-month period, we prospectively studied 41 children with blunt thoracic trauma (BTT) to determine the incidence and morbidity of cardiac injury in this population. Four patients died, and the data were incomplete in 10, leaving 27 for analysis. Serial electrocardiograms (ECG) were abnormal in 36% of the patients studied, serial creatine phosphokinase isoenzyme (CK-MB) ratios were elevated in 31%, echocardiogram showed septal dysfunction in 14%, and pyrophosphate scan showed grade 1 uptake in 14%. There was poor correlation among tests, since only four patients had more than one abnormal test. There was no significant difference in Injury Severity Score or Thoracic Abbreviated Injury Scale between patients with and without abnormal investigations. No patient in the study developed arrhythmias or cardiac failure. In 13 trauma-related deaths undergoing autopsy over the same period, including the four with thoracic trauma, none had evidence of cardiac injury. These results indicate a striking lack of consistency in the diagnosis of posttraumatic cardiac injury in children using standard investigations. The absence of adverse cardiac events in surviving patients and the lack of autopsy evidence of cardiac injury in the trauma deaths suggest that the actual incidence and clinical significance of these lesions in children is lower than generally reported. Children with BTT should be followed clinically, and reliance on screening tests should be avoided.

Adolescent↗

Primary fetal hydrothorax: natural history and management.

Primary fetal hydrothorax presents a wide spectrum of severity ranging from small, harmless effusions, to life-threatening thoracic compression. To define natural history and management, we reviewed 32 cases seen at two large perinatal centers from 1980 to 1987. Spontaneous resolution of the effusions was seen in three fetuses, all of whom survived. Three fetuses were electively terminated. The overall mortality was 53%. In the 24 untreated fetuses, sex and the presence of polyhydramnios did not influence mortality, but hydrops, gestational age less than 35 weeks at delivery, and bilateral effusions were associated with a poor prognosis. Five fetuses underwent in utero decompression. In four, thoracentesis was performed, with rapid reaccumulation of the effusion. All four died from pulmonary insufficiency. In the fifth fetus, a thoracoamniotic shunt permanently decompressed the effusion, with resolution of the hydrops, and delivery of a normal viable infant. We conclude that (1) primary fetal hydrothorax may resolve or progress to hydrops, necessitating close follow-up with ultrasound; (2) pulmonary hypoplasia as a result of undrained large pleural effusions may result in neonatal mortality; (3) the gestational age at both diagnosis and delivery, the development of hydrops, and bilaterality of effusions are important prognostic predictors; and (4) the fetus with large effusions and hydrops has a poor prognosis, and thoracic decompression with a thoracoamniotic shunt may prove life saving.

Female↗

Studies in fetal wound healing: I. A factor in fetal serum that stimulates deposition of hyaluronic acid.

Fetal wound healing without scar formations, fibrosis, or contracture might be accompanied by major differences in the wound extracellular matrix. The matrix of fetal wounds is rich in hyaluronic acid, a glycosaminoglycan found in high concentrations whenever there is tissue proliferation, regeneration, and repair. Although hyaluronic acid is a critical molecule for both embryonic development and wound healing, no factor has yet been identified that modulates hyaluronic acid in a consistent manner. We describe here a substance present in fetal sheep serum that stimulates hyaluronic acid synthesis by cultured fibroblasts. This glycoprotein factor appears to be ubiquitous, present in fetal sheep and bovine serum, reaching a peak in each at 40% of the way through gestation. This factor is also present in amniotic fluid. It might control hyaluronic acid deposition. In turn, hyaluronic acid, by creating an extracellular environment permissive for cell motility and proliferation, might be critical for fetal development. We suggest that the same sequence of events underlie the unique properties observed in fetal wound healing.

Animals↗

Studies in fetal wound healing: II. A fetal environment accelerates fibroblast migration in vitro.

We have used an in vitro model of wound healing using scratches made in a confluent monolayer of fibroblasts. The effects of fetal calf and postnatal calf serum on the migration of fibroblasts were compared. Differences between fetal and calf serum-incubated fibroblasts grown on coverslips were observed within 15 minutes of exposure. Cells in fetal serum began to change both shape and orientation and to move into the trough created by the scratch. The fibroblasts incubated in fetal calf serum completely filled in the trough within 16 hours while those incubated in calf serum did not do so even after 24 hours. We estimate that, at any point, there was a 50% lag time in the migration of the fibroblasts in the presence of postnatal calf serum. This difference in migration and filling was not a function of mitogenesis; the mitogenicity of the two sera were comparable. The results suggest that fibroblast migration in vitro is accelerated by the fetal serum. A similar mechanism may occur in vivo and may underlie the ability of the fetal wound to heal more rapidly.

Animals↗

Studies in fetal wound healing: III. Early deposition of fibronectin distinguishes fetal from adult wound healing.

Wound healing in the fetus proceeds through a series of steps that differ in the fetus and the adult. At each phase of this complex process, there is signaling between the tissue cells and the wound microenvironment, signals that are mediated by and through the extracellular matrix. We postulate that these signals occur earlier in fetal wounds, resulting in more rapid repair. To investigate this, we compared the first 24 hours of wound healing in the rabbit fetus and adult, using antibodies against key extracellular matrix macromolecular components: laminin, fibronectin, and type-specific collagens I, III, IV, and V. Fibronectin was the first matrix component to be deposited, and was visualized as early as four hours after fetal wounding and 12 hours after adult wounding. There was no evidence of new laminin or collagen deposition in either the fetal or adult wounds at any time point examined. The early deposition of fibronectin, a matrix adhesion molecule that provides a scaffolding for epithelial migration, may underlie the rapid reepithelialization observed in fetal wounds.

Animals↗

Appendicovesicostomy: a new technique for bladder diversion during reconstruction of cloacal exstrophy.

Urinary tract diversion in the reconstruction of cloacal exstrophy presents a difficult problem. Many methods have been used, but none has been found to be ideal. We describe a simple technique that incorporates the ileocecal plate in the bladder augmentation, and uses the appendix as a conduit for urinary diversion. This technique offers the advantages of primary closure, effective urinary drainage without tubes, and simplicity of bowel reconstruction with preservation of maximal absorptive surface.

Appendix↗

Biliary appendico-duodenostomy: a nonrefluxing conduit for biliary reconstruction.

Biliary conduits constructed during operations for choledochal cysts or biliary atresia are frequently complicated by reflux of gastrointestinal contents, stasis, and obstruction with resulting cholangitis. We have used the appendix as a biliary conduit for cases of biliary atresia and choledochal cyst, adapting the urologic technique of a tunneled, nonrefluxing anastomosis for reconstruction of the biliary tree--biliary appendico-duodenostomy (BAD). From our preliminary experience with this technique, it appears promising.

Anastomosis, Surgical↗

Studies in fetal wound healing. IV. Hyaluronic acid-stimulating activity distinguishes fetal wound fluid from adult wound fluid.

Recent clinical and experimental evidence suggests that the fetus responds to injury in a fashion fundamentally different from that of the adult. Our initial experience with human open fetal surgery reinforces experimental observations that the fetal wounds heal without the scarring, inflammation, and contraction that often accompany adult wounds. In this study we examine fetal wound fluid in an attempt to elucidate the control mechanisms that endow the fetus with unique healing properties. The extracellular matrix of fetal wounds is rich in hyaluronic acid, a glycosaminoglycan found in high concentrations whenever there is tissue proliferation, regeneration, and repair. We establish that wound fluid from the fetus contains high levels of hyaluronic acid-stimulating activity that may underlie the elevated deposition of hyaluronic acid in the fetal wound matrix. In contrast there was no hyaluronic acid-stimulating activity present in adult wound fluid. Hyaluronic acid, in turn, fosters an extracellular environment permissive for cell motility and proliferation that may account for the unique properties observed in fetal wound healing.

Age Factors↗