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Carnitine palmitoyltransferase (CPT) II deficiency, an inherited disorder of mitochondrial long-chain fatty-acid (LCFA) oxidation, results in two distinct clinical phenotypes, namely, an adult (muscular) form and an infantile (hepatocardiomuscular) form. The rationale of this phenotypic heterogeneity is poorly understood. The adult form of the disease is commonly ascribed to the Ser-113-Leu substitution in CPT II. Only few data are available regarding the molecular basis of the infantile form of the disease. We report herein a homozygous A-2399-C transversion predicting a Tyr-628-Ser substitution in a CPT II-deficient infant. In vitro expression of mutant cDNA in COS-1 cells demonstrated the responsibility of this mutation for the disease. Metabolic consequences of the SER-113-Leu and Tyr-628-Ser substitutions were studied in fibroblasts. The Tyr-628-Ser substitution (infantile form) resulted in a 10% CPT II residual activity, markedly impairing LCFA oxidation, whereas the Ser-113-Leu substitution (adult form) resulted in a 20% CPT II residual activity, with out consequence on LCFA oxidation. These data show that CPT II activity has to be reduced below a critical threshold in order for LCFA oxidation in fibroblasts to be impaired. The hypothesis that this critical threshold differs among tissues could provide a basis to explain phenotypic heterogeneity of CPT II deficiency.

Hereditary neuropathy with liability to pressure palsies (HNPP) is commonly associated with a 1.5-megabase deletion on chromosome 17p11.2-12. We analyzed the phenotypic expression of the deletion in 39 HNPP patients from 16 families carrying the deletion. Two-thirds of the individuals had episodes of acute mononeuropathy, often involving nerve territories of the upper limbs or brachial plexus; however, 41% of affected subjects were unaware of their disease, and 25% were almost or totally free of symptoms; one-third complained of chronic symptoms and four older patients had a picture of polyneuropathy. Electrophysiologic abnormalities differed among affected subjects, ranging from conduction abnormalities localized at common entrapment sites to diffuse conduction slowing, usually more evident at entrapment sites; patients from one family had preeminent proximal involvement. The spectrum of phenotypic expression of deletion-associated HNPP appears to be broader than previously thought. The prevalence of the disease is probably underestimated, and the availability of molecular diagnosis should increase disease detection.

Carnitine palmitoyltransferase II deficiency (CPT II) is an autosomal recessive disorder and the most frequent cause of hereditary myoglobinuria. We report the case of a young man who presented a severe fever-induced episode of rhabdomyolysis and myoglobinuria resulting in acute renal failure. Cultured skeletal muscle cells have been used for the biochemical and molecular characterization of the defect in this patient. Immunoblot analysis revealed reduced steady-state level of CPT II protein. A PCR-based method detected the common Ser113Leu substitution only in one allele, suggesting that the patient is a compound heterozygote for this common mutation and a different as yet unidentified mutation.

Deficiency of carnitine palmitoyltransferase type II (CPT II) is a clinically heterogeneous autosomal recessive disorder of lipid metabolism. The most common mutation in the CPT II gene is the S113L mutation, which substitutes leucine for serine at amino acid position 113. We studied an inbred family with three affected cousins with CPT II deficiency and found the S113L mutation to be present in a homozygous state in all three patients. Pedigree analysis traced the S113L mutation back to one common ancestor. Although the patients in this family have an identical genotype at the CPT II locus, their clinical picture ranges from asymptomatic to lethal.

This paper reports on results of a formal comparison of data excerpted from 3 different data sources regarding patients cared for in Italian Intensive Care Units (ICU) in 1992. The analysis was carried out in order to assess whether the administrative data routinely collected for reimbursement and policy issues are valid when compared with data from epidemiologic studies. First, using data from the Central Service for Health Planning (SCPS) a general description of the whole national scenario is shown. All the Italian data from 265 Italian hospitals having at least one ICU were analyzed. In these hospitals there were 2,357 ICU beds (4.3 beds/1000 inhabitants, with large regional variability). About 100,000 cases were identified (1% of all the hospital admissions received ICU care at some moment during the stay), with an overall hospital mortality rate of 17%. This estimate was largely different from those obtained from GiViTI data base (5100 patients from a national sample of 114 ICUs), where mortality rates were always higher (25 and 30%, for ICU and hospital mortality). Second, a more detailed analyses and comparison was carried out in the subsample of cases admitted in the Hospitals of the Regione Lombardia. In this case, beside the data from SCPS (No = 20580) and from GiViTI (No = 1121), the Regional data-base formed by all the discharge from 41 hospitals having at least one ICU were available (NO = 16674), allowing a formal comparison between estimates obtained from 3 different sources. In this sub-sample, although administrative data showed a good capability and satisfactory accuracy to describe the volume and socio-demographic and clinical characteristics of the cases when compared with GiViTI estimates, still a systematic underestimate of the overall ICU and hospital mortality was present. Moreover, an unexpected high rate of cases were apparently discharged alive from ICU (16.5 versus 32.6% in GiViTI). Tentative explanations and implications of these phenomena are discussed in the text. Finally, in the Lombardia sub-sample a formal description of the case-mix using the Diagnosis Related Group (DRG) system was carried out in order to identify strengths and limitations of this approach when adopted in the ICU setting. Overall, when data are analyzed according to the kind of Major Diagnostic Category (MDC), 75% of all cases were concentrated in 5 alone, with very peculiar concentration in some specific categories. For example, 45% of all the hospital admissions related to the multiple trauma were actually admitted in the ICU setting. At DRG level, fifty of the 493 DRGs available explained 65% of all the cases, showing an unexpected capability of this system to detect the ICU case-mix. The most represented surgical DRG was the number 107 (Coronary Arterial Bypass Graft, without catheterization) and the corresponding medical was the 28 (Cerebro Vascular Accident, excluding TIA).

Kennedy's disease, or spinal and bulbar muscular atrophy (SBMA), is a rare X-linked motoneuron disorder with variable signs of androgen insensitivity. It is associated with the expansion of a trinucleotide CAG repeat within the androgen receptor (AR) gene. We here report our clinical and molecular findings in two Italian families with Kennedy's disease. The increased size of the CAG repeat was demonstrated in four affected males and seven carrier females.

Background & Aims: Increasing evidence indicates that inherited susceptibility is important in the pathogenesis of colorectal neoplasia. The aim of this study was to clarify whether having only one first-degree relative with colorectal cancer increases the risk of developing adenomatous polyps and whether total colonoscopy is an appropriate screening measure in these patients., Methods: The frequency of such a history was evaluated in 397 asymptomatic patients who underwent total colonoscopy. Of these patients, 155 had colorectal polyps and the remaining 242 did not have polyps., Results: Among polyp cases, 27 of 155 (17.4%) had a positive history; among those without polyps, 12 of 242 (5.0%) had a positive history. Alternatively expressed, 27 of 39 patients (69%) with family history and 128 of 358 patients (36%) without family history had adenomas. The estimated risk for polyps associated with family history was 1.9. Among polyp cases, 14 of 27 patients (51.9%) with family history and 32 of 128 patients (25.0%) without family history had only proximal polyps (chi 2 test; P = 0.006; odds ratio, 3.2), In the same groups, frequency of high-grade dysplasia was 8 of 27 patients (29.6%) and 16 of 128 patients (12.5%), respectively (chi 2 test; P = 0.04; odds ratio, 2.9)., Conclusions: Relative to subjects with no family history, asymptomatic patients with one first-degree relative with colorectal cancer had nearly double the risk of developing adenomatous polyps, greater frequency of severely dysplastic lesions, and significantly higher frequency of proximal polyp location. This suggests that total colonoscopy screening is indicated in these subjects.

Carnitine palmitoyltransferase (CPT) II deficiency is the most common inherited disorder of lipid metabolism affecting skeletal muscle. To facilitate the identification of disease-causing mutations in the CPT II gene (CPT1), we have established the genomic organization of this gene. CPT1 spans approximately 20 kb of 1p32 and is composed of five exons ranging from 81 to 1305 bp. The sequences of the exon--intron boundaries were determined for each exon and conformed to the consensus splice junction sequences. The 5' and 3' untranslated regions in exon 1 and 5, respectively, were also determined, including the polyadenylation signal and the polyadenylation site. The mature transcript is predicted to be 3090 nt in length. CPT1 exons from CPT II-deficient patients were amplified and directly sequenced. Two novel disease-causing mutations were identified and characterized. The first mutation was a C-665-to-A transversion in exon 1 resulting in a proline-to-histidine substitution at residue 50 of the protein (P50H). This amino acid substitution occurs within a leucine-proline motif that is highly conserved in acyltransferases from different species. The mutation was detected in both alleles of patient 05SB of Italian ancestry, and in one allele of patients 11EG, 38PG, and 26FD of Italian, Dutch, and French ancestry, respectively. The second mutation was a rare G-2173-to-A transition in exon 5 causing an aspartic-acid-to-asparagine substitution at amino acid 553 (D553N) and the generation of a new MseI site. The mutation was detected only in one allele of patient 15MB, of Italian ancestry, who was also heterozygous for the common S113L substitution. Transfection experiments in COS cells demonstrated that both mutations drastically depressed the catalytic activity of CPT II. Biochemical characterization of P50H mutant CPT II in cultured cells from patient 05SB showed that the mutation does not affect substrate binding sites. Finally, immunoblot analysis demonstrated that both mutations were associated with markedly reduced steady-state level of the protein, thus indicating decreased stability of the mutant CPT II.

We have identified two partially overlapping genomic clones that contain part of the 5' regulatory region of the human carnitine palmitoyltransferase II gene. The 1.2 kb region upstream the transcription start site, as defined by primer extension experiments, shows promoter activity when inserted upstream of a reporter gene and contains a putative insulin responsive element.

During the last ten years, interest has been focussed on occupational exposure in thermoelectric power plants (i.e., coal dust, polycyclic aromatic hydrocarbons, dioxin, dielectric liquids, PCB's, asbestos, etc.), although available evidence on its effects on the health status of the occupational population are far from being definitive. A retrospective cohort study was carried out to investigate the association between exposure to risk factors and mortality for cancer in three thermoelectric power plants located in the north-east of Italy. The three plants studied started with oil and coal but since 1968 they utilized mostly coal as fuel. In spite of the different fuel used at the beginning, the production process has been fairly constant since the main conversion from oil to coal with a substantial increase in power production. A total of 1,772 male workers were included in the total study cohort and followed-up from 1968 to 1987, with a total of 22,090 person-years of exposure. Eighty percent of the cohort began to work in the plant before 30 years of age, and had a mean period of employment of 9.5 years. The cohort was completely traced to the end of the follow-up period by using an original computer system based on personal fiscal codes. Causes of death were ascertained in the municipalities where the deaths occurred and coded according to the International Classification of Disease, IX Revision. During the study period 68 deaths were observed with an SMR for all causes of death equal to 0.79.(ABSTRACT TRUNCATED AT 250 WORDS)

Mitochondrial diseases are heterogeneous and characterized by a primary defect of the mitochondrial energy output. Genetic defects of mitochondrial energy enzymes may be due to either nuclear DNA gene mutations or mitochondrial DNA (mtDNA) mutations. Among hereditary defects of nuclear-encoded mitochondrial enzymes, carnitine palmitoyltransferase II (CPT-II) deficiency and pyruvate dehydrogenase complex (PDHC) deficiency are of major interest to the neurologist. Several mutations in the CPT-II gene as well as in the X-linked E1 alpha subunit gene of PDHC have been reported and associated with different clinical phenotypes. mtDNA-related syndromes include mitochondrial encephalomyopathies (e.g. MELAS, MERRF, NARP, MIMyCa, etc.), 'pure' encephalopathies (e.g. LHON) and a few syndromes involving only non-neurological systems (e.g. Pearson's pancreas-bone marrow syndrome or diabetes mellitus). Three kinds of molecular lesions have been identified in mtDNA-related disorders: point mutations of protein-encoding mtDNA genes (mit- mutations), point mutations of mtDNA-tRNA genes (syn- mutations) and large-scale rearrangements of mtDNA (rho- mutations). Point mutations (mit- and syn+) are usually maternally inherited, while single large-scale mtDNA rearrangements are usually sporadic. Furthermore, mendelian traits leading to either qualitative or quantitative abnormalities of mtDNA (i.e. multiple mtDNA deletions and tissue-specific mtDNA depletion, respectively) are the first examples of genetic dysfunction of nuclear-mitochondrial communication. In most cases, the molecular detection of the known defects of mtDNA can be carried out by non-invasive techniques, thus making it an easy and relatively inexpensive procedure in the differential diagnosis of the mitochondrial disorders, a rapidly expanding area of clinical neurology.

Objectives: 1) to compare complexity and severity of the case-mix in the public and private sector, overall and across individual hospitals, and to examine their relative efficiency, by contrasting DRG and/or stage specific average length of stay (ALOS); 2) to assess the impact of a new contractual scheme based on a preassigned number of beddays for a restricted list of specific conditions., Data Sources: Discharge data on 940.670 admissions to 101 public hospitals and 185.161 admissions to 55 private hospitals in the Regione Lombardia in 1990, assigned to HCFA-DRGs, 8th version and to stages and substages of principal and unrelated diagnostic categories, based on Disease Staging., Result: The spread of the case-mix is higher in the private sector, which also shows a higher concentration of admissions across hospital for specific medical and surgical conditions. The proportion of more advanced stages of disease is higher in the public sector, for most of the most frequent diagnostic categories. Obstetric care, including abortion, is the largest single public sector activity, while it is virtually not existent in the private sector. Elective surgical procedures, including ENT, cataract and varicose veins surgery make up a substantial proportion of the private hospitals' case load. DRGs-specific ALOS is longer in public hospitals for the most frequent surgical DRGs, mainly due to their preoperative LOS. The net impact of the proposed contractual scheme will save substantial proportion of beddays for most of the conditions considered, except cataract and varicose veins surgery.

Sex crimes represent an important category of crimes. Physicians have to deal with them when treating victims in the emergency room. Forensic scientists, on their side, try to collect any trace of physical contact between victim and aggressor (sperm, fibres, etc.). But their success is largely dependent on the quality of the first intervention. Crucial evidence can be damaged or lost. Collaboration between physician and forensic scientist is essential when dealing with sex crimes to provide victims with the medical care they need, while using every piece of evidence which will allow the identification of the authors.

Carnitine palmitoyltransferase (CPT) II deficiency is the most common inherited disorder of lipid metabolism affecting skeletal muscle. We have identified a missense mutation (Ser113Leu) in one patient with the classical muscular symptomatology. Transfection experiments in COS cells demonstrate that the mutation drastically depresses the catalytic activity of CPT II. The mutation results in normal synthesis but a markedly reduced steady-state level of the protein, indicating decreased stability of mutant CPT II. The Ser113Leu mutation is the most frequent cause of CPT II deficiency. The mutation can be detected easily by restriction analysis enabling molecular diagnosis of most patients and identification of heterozygous carriers.

Deficiency of carnitine palmitoyltransferase II (CPTase II; palmitoyl-CoA:L-carnitine O-palmitoyltransferase, EC 2.3.1.21) is a clinically heterogeneous autosomal recessive disorder of energy metabolism. We studied the molecular basis of CPTase II deficiency in an early-onset patient presenting with hypoketotic hypoglycemia and cardiomyopathy. cDNA and genomic DNA analysis demonstrated that the patient was homozygous for a mutant CPTase II allele (termed ICV), which carried three missense mutations: a G-1203----A transition, predicting a Val-368----Ile substitution (V368I); a C-1992----T transition, predicting an Arg-631----Cys substitution (R631C); and an A-2040----G transition, predicting a Met-647----Val substitution (M647V). Genomic DNA analysis of family members showed that the mutations cosegregated with the disease in the family. However, screening of 59 healthy controls demonstrated that both the V368I and M647V mutations are sequence polymorphisms with allele frequencies of 0.5 and 0.25, respectively. By contrast, the R631C substitution was not detected in 22 normal individuals or in 12 of 14 CPTase II-deficient patients with the adult muscular form. Notably, 2 adult CPTase II-deficient patients were heterozygous for the ICV allele, thus suggesting compound heterozygosity for this and a different mutant allele. The consequences of the three mutations on enzyme activity were investigated by expressing normal and mutated CPTase II cDNAs in COS cells. The R631C substitution drastically depressed the catalytic activity of CPTase II, thus confirming that this is the crucial mutation. Interestingly, the V368I and M647V substitutions, which did not affect enzyme activity alone, exacerbated the effects of the R631C substitution. Biochemical characterization of mutant CPTase II in patient's cells showed that the mutations are associated with (i) severe reduction of Vmax (approximately 90%), (ii) normal apparent Km values, and (iii) decreased protein stability.

We have investigated the biogenesis of the biotin-binding alpha-subunit of propionyl-CoA carboxylase (alpha PCC) in cultured Buffalo rat liver cells. Cells were pulse-labeled with [35S]methionine, and the newly synthesized alpha PCC was immunoprecipitated with anti-alpha PCC antibodies and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Biotinylation of the alpha-subunit was detected by a mobility-shift assay following incubation with avidin. In the presence of biotin and the uncoupler, 2,4-dinitrophenol (DNP), alpha PCC precursor accumulated in the cytosol and was quantitatively biotinylated. Subsequent removal of the uncoupler in a "chase" protocol allowed the accumulated precursor to be translocated into mitochondria and cleaved to its mature form. When cells were grown in biotin-depleted medium and labeled in the presence of DNP, no biotinylation of the cytosolic precursor was observed. Nonetheless, the accumulated precursor was efficiently imported into mitochondria and cleaved to mature alpha PCC upon removal of the uncoupler. In parallel experiments in the absence of DNP, non-biotinylated mature alpha PCC accumulated in mitochondria; following addition of biotin, the apo-alpha PCC was converted rapidly to its holo-form. We conclude that both the alpha PCC precursor and its mature counterpart are competent for biotinylation and that biotinylated and nonbiotinylated alpha PCC precursor are competent for import by mitochondria.

A European approach for resource management and strategic planning has been implemented in the HOSCOM project of AIM by defining information standards needed across countries, as well as a methodology to measure resources and costs at the institutional and interinstitutional level. A Euro Health Data Base (EHDB) has been obtained in order to test data availability and comparability as well as to validate models through macrocomparisons using case-mix (DRG's, refined grouping, disease staging) and microcomparisons based on three diseases (cardiac valve replacement, diabetes mellitus and hip fracture). The EHDB's presently based on 274 164 medical record summaries sampled from 7 countries allowed us to build prototypes (using Clipper, Prolog and SQL) in order to export uniform aggregates in the different countries, with standard software tools for statistical comparisons. It showed the present feasibility of using case-mix based on the European Minimum Basic Data Set (MBDS) and the difficulty of obtaining uniform data on resources and costs other than length of stay across countries. Medical data confidentiality was assured but not yet population-based representativity. Given the present state of the EHDB, problems have been clearly identified in order to be solved by international research and development projects in the near future.

We have cloned and sequenced a cDNA encoding human liver carnitine palmitoyltransferase (CPTase; palmitoyl-CoA:L-carnitine O-palmitoyltransferase, EC 2.3.1.21), an inner mitochondrial membrane enzyme that plays a major role in the fatty acid oxidation pathway. Mixed oligonucleotide primers whose sequences were deduced from one tryptic peptide obtained from purified CPTase were used in a polymerase chain reaction, allowing the amplification of a 0.12-kilobase fragment of human genomic DNA encoding such a peptide. A 60-base-pair (bp) oligonucleotide synthesized on the basis of the sequence from this fragment was used for the screening of a cDNA library from human liver and hybridized to a cDNA insert of 2255 bp. This cDNA contains an open reading frame of 1974 bp that encodes a protein of 658 amino acid residues including 25 residues of an NH2-terminal leader peptide. The assignment of this open reading frame to human liver CPTase is confirmed by matches to seven different amino acid sequences of tryptic peptides derived from pure human CPTase and by the 82.2% homology with the amino acid sequence of rat CPTase. The NH2-terminal region of CPTase contains a leucine-proline motif that is shared by carnitine acetyl- and octanoyltransferases and by choline acetyltransferase. The gene encoding CPTase was assigned to human chromosome 1, region 1q12-1pter, by hybridization of CPTase cDNA with a DNA panel of 19 human-hamster somatic cell hybrids.

The activity of 34 general practitioners (GP) working in solo practices in six Local Health Units were assessed, as a preliminary step of a main study, to evaluate and possibly improve the quality of GP professional performance using peer review and feed-back information. A wide interpractice variation was observed in patient visit and patient visiting rates, drug and test prescribing, in- and out-patient referrals, as well as in the composition of the practice case-mix. The extent of interpractice variation for relevant actions in the process of care was unchanged after adjusting for case-mix, suggesting that case-mix differences have little effect in explaining differences among physicians' overall pattern of care and health care resource consumptions.

The aims of this study were to determine the diagnostic effectiveness of fasting and postprandial serum bile acid determinations in liver diseases, and to compare results with those of conventional liver function tests. In 322 patients with biopsy-proved liver disease and 93 healthy subjects, fasting and postprandial (2 hr) serum levels of cholic, chenodeoxycholic, and lithocholic acid conjugates and conventional liver function tests were evaluated. Data were subjected to variance and discriminant and factor analyses. Fasting serum bile acids were higher in patients when compared to controls and were significantly higher in severe than in mild liver diseases. Determination of cholic plus lithocholic acid provided the highest discrimination capacity. The percent of correct allocation was 75.4% for conventional liver function tests, 70.1% for fasting serum bile acids and increased to 79.6% when liver function tests plus serum bile acids were considered. Postprandial percentages were always lower than fasting. Factor analysis identified two factors possibly related to cytolysis and protein synthesis. The serum bile acid concentrations highly correlated with both factors. We conclude that serum bile acid determinations increase the diagnostic and discriminant capacities of liver function tests and are more sensitive and discriminant when obtained in fasting than postprandially.

Human muscle mitochondria reduced either NADP+ or NAD+ in the presence of L-malate and Mn2+ or Mg2+. After polyacrylamide slab gel electrophoresis and agarose gel isoelectrofocusing, two bands were seen in mitochondrial extract, one strictly NADP+-dependent and the other reacting with either NAD+ or NADP+. The two mitochondrial malic enzymes were separated by DEAE-Sepharose chromatography. The NAD+/NADP+-dependent enzyme was purified 1600-fold with a final yield of 34% and a final specific activity of 32.9 units/mg of protein by employing affinity chromatography on Agarose-ATP. SDS electrophoresis revealed a single band having an apparent Mr = 64,000. Estimates of the native apparent molecular weight upon gel filtration yielded a value of 140,300. Kinetic characterization showed that succinate and ATP were activator and inhibitor, respectively. In the absence of succinate the Km values for malate, NAD+ and NADP+ were 3.7, 0.13 and 0.78 mM, respectively; in the presence of succinate the Km value for malate was 1.9 mM. ATP was found to be an inhibitor competitive with malate, with a Ki (ATP) of 0.2 mM. This is the first report to show that mammalian skeletal muscle mitochondria contains two distinct malic enzymes, one active with either NAD+ or NADP+ and the other active only with NADP+.

The prevalence of gallstone disease (cholelithiasis and previous cholecystectomy for gallstones) in the population of the town of Sirmione, Italy, examined by ultrasonography, was 6.7% in men and 14.6% in women, ranging from 18 to 65 yr of age (overall prevalence = 11%). The prevalence of cholelithiasis in the same age span was 6.9% (4.5% in men and 8.9% in women). Prevalence of cholelithiasis increased with age in both sexes. Twenty-two percent of gallstone subjects suffered from biliary pain vs. 2% of subjects without gallstones. No difference was observed in the frequency of nonspecific symptoms between subjects with and without gallstones. Of the 132 gallstone subjects, 108 (82%) were not aware of having gallstones prior to the study. Prevalence of gallstone disease was found to be higher in obese and hypertriglyceridemic subjects and to increase with the number of pregnancies.

We have cloned and sequenced cDNAs encoding the alpha-subunit of rat liver propionyl-CoA carboxylase (PCC), a biotin-dependent, mitochondrial matrix protein. The full-length cDNA spans 3327 base pairs, has a long (895 base pairs) 5'-untranslated region, and encodes a protein of 721 amino acids. In vitro transcription and translation of the full-length rat alpha-PCC cDNA produces a product which is immunoprecipitable with antibodies specific to PCC and has the same apparent molecular weight as in vivo synthesized alpha-PCC. Rat liver alpha-PCC precursor is not quantitatively biotinylated when synthesized in a cell-free rabbit reticulocyte system. Nevertheless, when incubated with isolated rat liver mitochondria in vitro, the precursor is imported and proteolytically cleaved to its mature form. A sequence comparison of rat liver alpha-PCC and other biotinylated polypeptides reveals the absolute conservation of three glycines and one valine in the region surrounding the biotinylated lysine residue. This pattern of conserved residues is also present in lipoylated proteins, where lipoic acid is similarly, covalently attached to a lysine residue. A possible functional role for the conserved glycine residues and further sequence similarity surrounding the site of biotinylation and lipoylation is discussed.

Recurrence is a major problem in the medical treatment of gallstones but its extent is still uncertain. The aim of this study was to determine the magnitude of this event and to assess the effectiveness of a postdissolution treatment in preventing it. We evaluated the long-term recurrence rate after 96 confirmed dissolutions observed in 86 subjects (71 women, 15 men) over a 12-yr follow-up period. A low-dose postdissolution treatment (ursodeoxycholic acid, 300 mg/day) was administered to 36 subjects, whereas in the remaining 60 cases no postdissolution treatment was given. By actuarial life-table analysis, the cumulative proportion of gallstone recurrence was 12.5% at the first year, rising to 61% at the 11th year. Postdissolution treatment was effective in reducing the frequency of gallstone recurrence (p = 0.0067), but this was mainly related to its effect on younger subjects (less than or equal to 50 yr old). In older subjects the recurrence rate was unaffected by treatment. The probability of gallstone recurrence was significantly higher in subjects with multiple stones before dissolution treatment than in those who had had solitary stones (p = 0.0091). No other factor predictive of gallstone recurrence could be identified.

1. An NADP+-dependent malic enzyme was purified 7940-fold from the cytosolic fraction of human skeletal muscle with a final yield of 55.8% and a specific activity of 38.91 units/mg of protein. 2. The purification to homogeneity was achieved by ammonium sulfate fractionation, DEAE-Sepharose chromatography, affinity chromatography on NADP+-Agarose, gel filtration on Sephacryl S-300 and rechromatography on the affinity column. 3. Either Mn2+ or Mg2+ was required for activity: the pH optima with Mn2+ and Mg2+ were 8.1 and 7.5, respectively. The enzyme showed Michaelis-Menten kinetics. At pH 7.5 the apparent Km values with Mn2+ and Mg2+ for L-malate and NADP+ were 0.246 mM and 5.8 microM, and 0.304 mM and 5.8 microM, respectively. The Km values with Mn2+ for pyruvate, NADPH and bicarbonate were 8.6 mM, 6.1 microM and 22.2 mM, respectively. 4. The enzyme was also able to decarboxylate malate in the presence of NAD+. At pH 7.5 the reaction rate was approximately 10% of the rate in the presence of NADP+, with a Km value for NAD+ of 13.9 mM. 5. The following physical parameters were established: s0(20.w) = 10.48, Stokes' radius = 5.61 nm, pI = 5.72 Mr of the dissociated enzyme = 61,800. The estimates of the native apparent Mr yielded a value of 313,000 upon gel filtration, and 255,400 with f/fo = 1.33 by combining the chromatographic data with the sedimentation measurements. 6. The electron microscopy analysis of the uranyl acetate-stained enzyme revealed a tetrameric structure. 7. Investigations to detect sugar moieties indicated that the enzyme contains carbohydrate side chains, a property not previously reported for any other malic enzyme.

A child with myopathy and systemic carnitine deficiency died at age 8 years in an acute metabolic attack. He had glutaric aciduria type II, and his cultured fibroblasts contained normal activity of four different acyl CoA dehydrogenases, but there was deficiency of electron transfer flavoprotein:ubiquinone oxidoreductase (ETF-QO). This enzyme is thought to reduce coenzyme Q in the respiratory chain, funneling reducing equivalents from seven flavoproteins in the beta-oxidation of acyl CoAs. There was massive urinary excretion of the short-chain acylcarnitines that accumulated in mitochondria as a result of the ETF-QO defect. Carnitine therefore acts as a buffer for excessive accumulation of intramitochondrial acyl CoAs, and defective beta-oxidation can cause carnitine insufficiency.

Cholesterol gallstones are dissolved in man by chenodeoxycholic acid (CDCA) and ursodeoxycholic acid (UDCA). To test the comparative efficacy of these two cholelitholytic bile acids, 223 gallstones patients were randomly treated with either UDCA or CDCA at two different doses: 7 to 8 mg per kg per day and 14 to 15 mg per kg per day. Efficacy and factors influencing dissolution (dose, size of the stones, and time) were evaluated after 3, 6, and 12 months of treatment. UDCA was significantly more efficacious than was CDCA after 3 and 6 months of treatment, whereas after 12 months, no significant differences were observed. UDCA was equally effective at high and low doses, both on small and large stones. CDCA was significantly more effective at high doses and on small stones. Seventy-four per cent of the total dissolutions with UDCA and 42% with CDCA occurred within the first 6 months of treatment. Diarrhea and hypertransaminasemia occurred only in the CDCA-treated patients. We conclude that UDCA seems to be the bile acid of choice in dissolving cholesterol gallstones.