Beta mercaptolactate-cysteine disulfide: analog of cystine in the urine of a mentally retarded patient.

beta-Mercaptolactate-cysteine disulfide, a hitherto undescribed analog of cystine, was isolated from the urine of a mentally retarded patient. The propertis of this substance are described, and its structure is confirmed by mass spectrometry and by partial synthesis.

The effect of ketorolac on anteroposterior knee laxity after anterior cruciate ligament reconstruction.

UNLABELLED: This study investigated the effect of ketorolac on anteroposterior laxity after anterior cruciate ligament (ACL) reconstruction. A total of 168 ACL reconstructions performed between July 2003 and November 2004 were reviewed. The 6-week KT-1000 manual maximum differences between the ACL-reconstructed knee and nonoperative knee were compared for patients who received ketorolac and those who did not. Mean manual maximum difference in anterior displacement was 0.6 mm in the ketorolac group and -0.6 mm in the non-ketorolac group (P=.03). When bone-patellar tendon grafts were analyzed as a separate group, mean manual maximum difference was 0.5 mm in the ketorolac group and -1.4 mm in the non-ketorolac group (P=.007). When hamstring grafts were analyzed separately, mean manual maximum difference was 0.7 mm in the ketorolac group and 0.4 mm in the non-ketorolac group (P=.59). The use of ketorolac during bone-patellar tendon autograft ACL reconstruction was associated with increased AP laxity at 6 weeks postoperatively. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Sanfilippo syndrome type D: identification of the first mutation in the N-acetylglucosamine-6-sulphatase gene.

Mucopolysaccharidosis type IIID is the least common of the four subtypes of Sanfilippo syndrome. It is caused by a deficiency of N-acetylglucosamine-6-sulphatase, which is one of the enzymes involved in the catabolism of heparan sulphate. We present the clinical, biochemical, and, for the first time, the molecular diagnosis of a patient with Sanfilippo D disease. The patient was found to be homozygous for a single base pair deletion (c1169delA), which will cause a frameshift and premature termination of the protein. Accurate carrier detection is now available for other members of this consanguineous family.

Prenatal diagnosis of lysosomal storage diseases.

The prenatal diagnosis of lysosomal storage disorders can be achieved, once the diagnosis is confirmed in the index case, by a variety of techniques including analysis of amniotic fluid, asay of enzymic activity in cultured amniotic fluid cells, cultured chorionic villus cells and by direct assay of activity in chorionic villus samples. These studies can be accompanied by ultrastructural observations which give an independent means of diagnosis. In some instances molecular genetic studies for mutation detection or linkage analysis are appropriate for prenatal diagnosis. Pseudodeficiencies of some of the lysosomal enzymes, which cause no clinical problems, can complicate the initial diagnosis particularly in metachromatic leucodystrophy where the pseudodeficiency is more common than the disease itself. Mutation analysis as well as enzyme assay is necessary not only in the index case but also in the parents before the same techniques are applied to a sample for prenatal diagnosis. A large number of lysosomal storage disorders may present as fetal hydrops and the diagnosis can be established at this late stage by fetal blood sampling and examination by microscopy as well as by biochemical assay of the appropriate enzyme or metabolite in amniotic fluid. All prenatal diagnoses in which an affected fetus is indicated should have confirmation of the diagnosis as soon as possible to reassure anxious parents, and to act as audit of the laboratory's competence to undertake prenatal diagnosis. A combined approach to prenatal diagnosis involving biochemical, molecular genetic and morphological studies is recommended.

Cardiac sarcoplasmic reticulum. Effects of an atherogenic diet during the neonatal and juvenile period.

The effect on the cardiac sarcoplasmic reticulum of an atherogenic (1% cholesterol) diet fed during the neonatal vs the juvenile period of life was studied in Yorkshire swine. Male piglets were randomly assigned at birth to 1 of 4 groups: group I (control), group II (lactation feeding), group III (juvenile period feeding) and group IV (lactation and juvenile feeding). All animals were killed at 55 weeks of age and cardiac sarcoplasmic reticulum (SR) isolated for assay of calcium uptake, Ca2+-Mg2+ ATPase activity, and lipid analysis by thin-layer chromatography and gas chromatography. The amount of cholesterol/mg SR protein and the cholesterol/phospholipid ratio were higher in the animals fed during lactation (groups II and IV) and lower in those fed only during the juvenile period (group III). Phospholipid fatty acid patterns as measured by gas chromatography were unaltered in any group. Calcium uptake was markedly diminished in all experimental conditions: group II 47%, group III 65% and group IV 96%. Compared to the observed changes in calcium transport, the ATP hydrolytic activity was relatively less affected. Only in group IV a significant decrease (41%) was seen. Groups II and III show no change in ATP hydrolytic activity. The decrease in calcium uptake and altered cholesterol/phospholipid ratio without effect on ATP hydrolytic activity is consistent with an uncoupling of calcium transport related to the atherogenic diet in early life.

Effect of tissue culture storage on the in vivo survival of canine osteochondral allografts.

In vitro studies in our laboratory have shown that the biomechanical and biochemical characteristics of osteochondral grafts can be preserved for as long as 28 days under tissue culture conditions. This study represents an attempt to extend these results to an in vivo model. In adult mongrel dogs, either an autograft, a fresh allograft, or a stored allograft was placed in a standardized defect on the weight-bearing surface of the medial femoral condyle. The stored grafts were kept at 4 degrees C in tissue culture medium for 14 days prior to implantation. The animals were killed at 12 weeks. Cartilage from the contralateral knee served as a control. The modulus and permeability of the cartilage were assessed with confined compression creep tests. The collagen and glycosaminoglycan contents were measured, and the cartilage was analyzed histologically with hematoxylin and eosin and safranin O stains. Grossly, the cartilage appeared viable at harvest. The histologic results were similar in the treatment groups, with the same spectrum of mild degenerative changes being noted in each group. The glycosaminoglycan content was significantly less in the autograft group than in its control group and than in the fresh allograft group. The glycosaminoglycan content did not differ significantly between fresh and stored allografts. The collagen content, modulus, and permeability did not differ either between experimental and control groups or between graft types. Our results support the conclusion that osteochondral allografts can be stored for as many as 14 days without significantly affecting the results of the procedure.

A high performance liquid chromatography method for the analysis of 35S-cystine: application to the diagnosis of cystinosis.

An HPLC method for the measurement of radioactively labelled cystine is described. This method has been applied to studies of the uptake and retention of 35S-cystine by cultured cells. Radioactive cystine was measured, as a proportion of the non-protein labelled products in cultured cells incubated with medium containing 35S-cystine. Cells from healthy individuals contained less than 7% cystine whereas cells from cases of cystinosis contained at least 19% cystine. The method has been applied to the prenatal diagnosis of cystinosis. The use of flow radioactivity detection provides the advantages of rapid diagnosis and quantitation of metabolites.

Pre- and postnatal diagnosis of patients with CLN1 and CLN2 by assay of palmitoyl-protein thioesterase and tripeptidyl-peptidase I activities.

Palmitoyl-protein thioesterase (PPT) and tripeptidyl-peptidase I (TPP-I) activities were measured in leucocytes and fibroblasts. Fourteen patients were confirmed as having late infantile neuronal ceroid lipofuscinosis due to a deficiency of TPP-I activity. This included one patient with a milder and more protracted form of the disease. In addition this enzyme deficiency was found in a clinically normal younger sibling of a patient. Of particular importance was the finding of normal TPP-I activity in two patients who had been diagnosed as having classical late infantile neuronal ceroid lipofuscinosis. A deficiency of PPT was confirmed retrospectively in stored fibroblasts from two patients who had already died having been diagnosed with infantile neuronal ceroid lipofuscinosis. Palmitoyl-protein thioesterase or TPP-I activities were measured in chorionic villi and cultured chorionic villi cells in three pregnancies. The enzyme results were confirmed by mutational analysis if the mutations were known, or, in the case of the pregnancy at risk for infantile neuronal ceroid lipofuscinosis by electron microscopy of the chorionic villi. Our results show that assay of PPT and TPP-I is reliable in the diagnosis of patients with mutations in the CLN1 and CLN2 genes. It is imperative to assay these enzymes in all patients to confirm the diagnosis and ensure accurate genetic counselling of other family members. Once an enzyme deficiency has been confirmed reliable prenatal diagnosis is available even if both mutations have not been detected.

The effects of transection of the anterior cruciate ligament on healing of the medial collateral ligament. A biomechanical study of the knee in dogs.

The effect of concurrent injury to the anterior cruciate ligament on the healing of injuries of the medial collateral ligament was studied in dogs. In Group I, isolated transection of the medial collateral ligament was performed; in Group II, transection of the medial collateral ligament with partial transection of the anterior cruciate ligament; and in Group III, complete transection of both the medial collateral ligament and the anterior cruciate ligament. The three groups of animals were examined six and twelve weeks postoperatively with respect to varus-valgus rotation of the knee and tensile properties of the femur-medial collateral ligament-tibia complex. The varus-valgus rotation of the knee was found to be the largest in Group-III specimens at all time-periods and was 3.5 times greater than the control values at twelve weeks. Group-I and Group-II specimens also showed large varus-valgus rotations at time zero, but the rotations returned to the control values by twelve weeks. For the structural properties of the femur-medial collateral ligament-tibia complex, the values for ultimate load for Groups I and II reached the control values by twelve weeks, while that for Group III remained at only 80 per cent of the control value. Both energy absorbed at failure and linear stiffness for all three groups were less than those for the controls at six weeks, and only linear stiffness returned to the control values by twelve weeks. For the mechanical (material) properties of the healed ligament substance, the values for modulus and tensile strength were markedly lower than the control values for all groups at six weeks. By twelve weeks, the tensile strength of Group-I specimens had increased to 52 per cent of the control value, while those of Groups II and III were only 45 and 14 per cent, respectively. Our results demonstrate that healing of the transected medial collateral ligament is adversely affected by concomitant transection of the anterior cruciate ligament. Both varus-valgus rotation and mechanical properties of the healed ligament failed to recover in knees that had combined transection of the anterior cruciate and medial collateral ligaments. The structural properties of the femur-medial collateral ligament-tibia complex in tension recovered more rapidly as a consequence of the large mass of reparative tissue that formed in the medial collateral ligament of the anterior cruciate-deficient knees.

Perioperative nutrition and postoperative complications in patients undergoing spinal surgery.

STUDY DESIGN: The authors undertook a three-part study to better understand the impact of perioperative nutritional status on postoperative complications in patients undergoing spinal surgery. In preliminary Parts I and II, the authors targeted two groups of patients who are particularly nutritionally challenged. In Part III, they studied a large group of consecutive patients undergoing routine lumbar spinal fusion. OBJECTIVES: To determine whether preoperative nutritional status was a significant predictor of postoperative complications in patients undergoing elective lumbar spinal fusion. SUMMARY OF BACKGROUND DATA: In Part I, 27 patients treated surgically for vertebral osteomyelitis were divided into two groups based on their preoperative nutritional status. Twenty-four of the 26 postoperative complications were in the malnourished group (P < 0.001). In Part II, 15 (75%) of 20 patients treated surgically for spinal cord injury were found to become malnourished in the postoperative period. Seventeen complications were noted, all in the malnourished group (P = 0.001). METHODS: One hundred fourteen consecutive patients undergoing selective lumbar decompression and fusion were identified and their records reviewed. In addition to preoperative nutritional status, data gathered included age, sex, height, weight, past medical history, steroid use, alcohol use, tobacco use, type of bone graft (allograft vs. autograft), history of previous lumbar surgery, number of levels fused, and use of spinal instrumentation. RESULTS: Eleven of 13 postoperative infectious complications (10 deep wound infections) were noted in the malnourished group (P < 0.001). By stepwise logistic regression analysis, preoperative nutritional status was an extremely significant independent predictor of postoperative complications in patients undergoing elective lumbar spinal fusion (P = 0.0018). CONCLUSIONS: The prevalence data in our study population suggest that a large number (25%) of patients undergoing elective lumbar spine surgery are nourished inadequately at surgery. This number is higher (42%) in older patients. The authors recommend that close attention be paid to the perioperative nutritional status of patients undergoing lumbar spinal surgery. Patients with suboptimal nutritional parameters should be supplemented and replenished before elective surgery.

Effect of altrenogest and Lutalyse on parturition control, plasma progesterone, unconjugated estrogen and 13,14-dihydro-15-keto-prostaglandin F2 alpha in sows.

To investigate control of parturition time, 154 sows farrowing 220 litters at three locations were treated with altrenogest and Lutalyse (PG). The four treatment groups were: 1) no treatment (control group); 2) an im injection of 15 mg of PG at 1000 on d 111, 112 or 113 of gestation (d 0 = first day of estrus and gestation); 3) altrenogest (20 mg X sow-1 X d-1) fed twice daily for 4 d starting on d 109, 110 or 111; and 4) altrenogest and an injection of PG at 1000 on the day after the last feeding of altrenogest. Control sows at the University of Delaware (UD), University of Maryland (UM) and USDA, Beltsville Agricultural Research Center (BARC) had mean gestation lengths of 113.5, 114.2 and 115.7 d and live pigs/litter were 10.5, 11.0 and 7.4, respectively. Altrenogest started by d 110 prevented unscheduled early farrowing and increased (P less than .01) gestation length by 1.7 and 1.1 d, respectively, at UD and UM, but had not effect at BARC. The time from PG to parturition was 24.3, 22.6 and 34.4 h, respectively, at UD, UM and BARC. More sows at UD and UM farrowed between 0700 and 1700 on the expected day of parturition after injection of PG (59.3%) than with no PG (20.7%; P less than .05). The high incidence of small litters (less than six pigs) from sows inseminated with frozen semen at BARC resulted in negative correlations of live pigs/litter with gestation length (r = -.533, P = .0001) and with time from PG injection to birth of first pig (r = -.425, P = .017); these correlations were not significant at UD and UM where only natural service was used.(ABSTRACT TRUNCATED AT 250 WORDS)