A Weight of Evidence approach to support the assessment of the quality of Manila clam farming sites in a coastal lagoon.

Aquaculture productivity in coastal lagoons is endangered by a complex interplay of anthropogenic and environmental factors, amplified by the effects of climate change in these sensitive areas. To reach a more comprehensive assessment of farming sites quality, a quantitative Weight of Evidence approach (QWoE) is applied for the first time to data collected at four Manila clam (R. philippinarum) farming sites in the Venice lagoon (Italy). This included sediment quality, chemical bioaccumulation, and biological responses. Results revealed a greater hazard for sites closer to the open sea. In these areas, the combination of sediment characteristics and a higher frequency of salinity and temperature stress could explain the alterations measured at a transcriptional and biomarker level. The findings demonstrate that a QWoE approach that integrates multiple sources of evidence should also include physicochemical conditions in order to better understand the impacts of human activities and other stressors on clam aquaculture productivity.

Guideline Application in Real world: multi-Institutional Based survey of Adjuvant and first-Line pancreatic Ductal adenocarcinoma treatment in Italy. Primary analysis of the GARIBALDI survey.

BACKGROUND: Information about the adherence to scientific societies guidelines in the 'real-world' therapeutic management of oncological patients are lacking. This multicenter, prospective survey was aimed to improve the knowledge relative to 2017-2018 recommendations of the Italian Association of Medical Oncology (AIOM). PATIENTS AND METHODS: Treatment-naive adult patients with pancreatic adenocarcinoma were enrolled. Group A received adjuvant therapy, group B received primary chemotherapy, and group C had metastatic disease. The results on patients accrued until 31 October 2019 with a mature follow-up were presented. RESULTS: Since July 2017, 833 eligible patients of 923 (90%) were enrolled in 44 Italian centers. The median age was 69 years (range 36-89 years; 24% >75 years); 48% were female; 93% had Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1; group A: 16%, group B: 30%; group C: 54%; 72% Nord, 13% Center, 15% South. In group A, guidelines adherence was 68% [95% confidence interval (CI) 59% to 76%]; 53% of patients received gemcitabine and 15% gemcitabine + capecitabine; median CA19.9 was 29 (range 0-7300; not reported 15%); median survival was 36.4 months (95% CI 27.5-47.3 months). In group B, guidelines adherence was 96% (95% CI 92% to 98%); 55% of patients received nab-paclitaxel + gemcitabine, 27% FOLFIRINOX, 12% gemcitabine, and 3% clinical trial; median CA19.9 was 337 (range 0-20220; not reported 9%); median survival was 18.1 months (95% CI 15.6-19.9 months). In group C, guidelines adherence was 96% (95% CI 94% to 98%); 71% of patients received nab-paclitaxel + gemcitabine, 16% gemcitabine, 8% FOLFIRINOX, and 4% clinical trial; liver and lung metastases were reported in 76% and 23% of patients, respectively; median CA19.9 value was 760 (range 0-1374500; not reported 9%); median survival was 10.0 months (95% CI 9.1-11.1 months). CONCLUSIONS: The GARIBALDI survey shows a very high rate of adherence to guidelines and survival outcome in line with the literature. CA19.9 testing should be enhanced; nutritional and psychological counseling represent an unmet need. Enrollment to assess adherence to updated AIOM guidelines is ongoing.

Effects of environmental concentrations of the fragrance amyl salicylate on the mediterranean mussel Mytilus galloprovincialis.

Amyl salicylate (AS) is a fragrance massively used as a personal care product and following the discharged in wastewaters may end up in the aquatic environment representing a potential threat for the ecosystem and living organisms. AS was recently detected in water of the Venice Lagoon, a vulnerable area continuously subjected to the income of anthropogenic chemicals. The lagoon is a relevant area for mollusc farming, including the Mediterranean mussels (Mytilus galloprovincialis) having an important economic and ecological role. Despite high levels of AS occurred in water of the Lagoon of Venice, no studies investigated the possible consequences of AS exposures on species inhabiting this ecosystem to date. For the first time, we applied a multidisciplinary approach to investigate the potential effects of the fragrance AS on Mediterranean mussels. To reach such a goal, bioaccumulation, cellular, biochemical, and molecular analyses (RNA-seq and microbiota characterization) were measured in mussels treated for 7 and 14 days with different AS Venice lagoon environmental levels (0.1 and 0.5 µg L-1). Despite chemical investigations suggested low AS bioaccumulation capability, cellular and molecular analyses highlighted the disruption of several key cellular processes after the prolonged exposures to the high AS concentration. Among them, potential immunotoxicity and changes in transcriptional regulation of pathways involved in energy metabolism, stress response, apoptosis and cell death regulations have been observed. Conversely, exposure to the low AS concentration demonstrated weak transcriptional changes and transient increased representation of opportunistic pathogens, as Arcobacter genus and Vibrio aestuarianus. Summarizing, this study provides the first overview on the effects of AS on one of the most widely farmed mollusk species.

Chemotherapy toxicity and activity in patients with pancreatic ductal adenocarcinoma and germline BRCA1-2 pathogenic variants (gBRCA1-2pv): a multicenter survey.

BACKGROUND: Germline BRCA1-2 pathogenic variants (gBRCA1-2pv)-related pancreatic ductal adenocarcinoma (PDAC) showed increased sensitivity to DNA cross-linking agents. This study aimed at exploring safety profile, dose intensity, and activity of different chemotherapy regimens in this setting. PATIENTS AND METHODS: gBRCA1-2pv PDAC patients of any age and clinical tumor stage who completed a first course of chemotherapy were eligible. A descriptive analysis of chemotherapy toxicity, dose intensity, response, and survival outcomes was performed. RESULTS: A total of 85 gBRCA1-2pv PDAC patients treated in 21 Italian centers between December 2008 and March 2021were enrolled. Seventy-four patients were assessable for toxicity and dose intensity, 83 for outcome. Dose intensity was as follows: nab-paclitaxel 72%, gemcitabine 76% (AG); cisplatin 75%, nab-paclitaxel 73%, capecitabine 73%, and gemcitabine 65% (PAXG); fluorouracil 35%, irinotecan 58%, and oxaliplatin 64% (FOLFIRINOX). When compared with the literature, grade 3-4 neutropenia, thrombocytopenia, and diarrhea were increased with PAXG, and unmodified with AG and FOLFIRINOX. RECIST responses were numerically higher with the three- (81%) or four-drug (73%) platinum-containing regimens that outperformed AG (41%) and oxaliplatin-based doublets (56%). Carbohydrate antigen 19.9 (CA19.9) reduction >89% at nadir was reported in two-third of metastatic patients treated with triplets and quadruplets, as opposed to 33% and 45% of patients receiving oxaliplatin-based doublets or AG, respectively. All patients receiving AG experienced disease progression, with a median progression-free survival (mPFS) of 6.4 months, while patients treated with platinum-containing triplets or quadruplets had an mPFS >10.8 months. Albeit still immature, data on overall survival seemed to parallel those on PFS. CONCLUSIONS: Our data, as opposed to figures expected from the literature, highlighted that platinum-based regimens provoked an increased toxicity on proliferating cells, when dose intensity was maintained, or an as-expected toxicity, when dose intensity was reduced, while no change in toxicity and dose intensity was evident with AG. Furthermore, an apparently improved outcome of platinum-based triplets or quadruplets over other regimens was observed.

Amino-nanopolystyrene exposures of oyster (Crassostrea gigas) embryos induced no apparent intergenerational effects.

Early life stages (ELS) of numerous marine invertebrates mustcope with man-made contaminants, including plastic debris, during their pelagic phase. Among the diversity of plastic particles, nano-sized debris, known as nanoplastics, can induce effects with severe outcomes in ELS of various biological models, including the Pacific oyster Crassostrea gigas. Here, we investigated the effects of a sub-lethal dose (0.1 µg mL-1) of 50 nm polystyrene nanobeads (nano-PS) with amine functions on oyster embryos (24 h exposure) and we assessed consequences on larval and adult performances over two generations of oysters. Only a few effects were observed. Lipid analyses revealed that first-generation (G1) embryos exposed to nano-PS displayed a relative increase in cardiolipin content (+9.7%), suggesting a potential modification of mitochondrial functioning. G1-larvae issued from exposed embryos showed decreases in larval growth (-9%) and lipid storage (-20%). No effect was observed at the G1 adult stage in terms of growth, ecophysiological parameters (clearance and respiration rates, absorption efficiency), or reproductive outputs (gonadic development, gamete quality). Second generation (G2) larvae issued from control G1 displayed a significant growth reduction after G2 embryonic exposure to nano-PS (-24%) compared to control (as observed at the first generation), while no intergenerational effect was detected on G2 larvae issued from G1 exposed embryos. Overall, the present experimental study suggests a low incidence of a short embryonic exposure to nano-PS on oyster phenotypes along the entire life cycle until the next larval generation.

[Permanent environmental disinfection techniques in hospital settings with infectious risk]. / Tecniche di disinfezione ambientale permanente negli ambienti ospedalieri a rischio infettivo.

While the world's economies avoid the COVID-19 pandemic blockade, there is an urgent need for technologies aimed at reducing the transmission of COVID-19 in confined spaces such as hospital environments. Although the cleaning and disinfection procedures now have rather complex and sophisticated weapons, they do not seem to be sufficient to continuously maintain low levels of environmental microbiological contamination. This result can now be achieved through the cross-use, in space and time, of improved, more efficient and effective technologies. This result can now be achieved through the cross-use, in space and time, of improved technologies. This work highlights the possibility of crossing and cooperation of different disinfection techniques, such as to keep the microbial and viral load low over time.

Epidemiology of HPV-related female cancers in the Umbria region of Italy: pre-vaccination period.

The authors describe the incidence and mortality rates of human papillomavirus (HPV)-related female cancers in Umbria (Italy) in the pre-vaccination period from 1978-2008. Joinpoint regression was applied on age-adjusted incidence and mortality rates to evaluate temporal trends. Mouth and pharynx cancers incidence and mortality trends decreased about three percent per year. For anus and anal canal cancer, incidence and mortality trends presented a non-significant decrease. For malignant neoplasm of vulva, a significant change was found in incidence trend: the annual percentage change decreased from 2001 (- 1.8%). Mortality trend showed a non-significant decrease. Incidence and mortality rates from vaginal cancer were non-significantly decreased. For malignant neoplasm of cervix uteri, incidence rates showed a significant decrease by 2.1% per year. Mortality rates decreased as well, although non-significantly. HPV-related cancers consistently decreased in Umbria. This trend may be a consequence of safer sexual behavior. For cervical cancer, a combination of opportunistic and programmed screening led to a much-reduced disease burden. It is expected that the implementation of vaccination in the future will lead to a further decrease of HPV-related cancer incidence and mortality.

Baseline elevated leukocyte count in peripheral blood is associated with poor survival in patients with advanced non-small cell lung cancer: a prognostic model.

PURPOSE: We aimed to investigate the prognostic significance of several baseline variables in stage IIIB-IV non-small cell lung cancer to create a model based on independent prognostic factors. METHODS/RESULTS: A total of 320 patients were treated with last generation chemotherapy regimens. The majority of patients received treatment with cisplatin + gemcitabine or gemcitabine alone if older than 70 years or with an ECOG performance status (PS) = 2. Performance status of 2, squamous histology, number of metastatic sites >2, presence of bone, brain, liver and contralateral lung metastases and elevated leukocyte count in peripheral blood were all statistically significant prognostic factors in univariate analyses whereas the other tested variables (sex, stage, age, presence of adrenal gland and skin metastases) were not. Subsequently, a multivariate Cox's regression analysis identified PS 2 (P < 0.001, hazard ratio 2.57), elevated leukocyte count (P < 0.001, hazard ratio 1.79), squamous histology (P = 0.005, hazard ratio 1.45) and presence of brain metastases (P = 0.035, hazard ratio 1.5) as independent prognostic factors for poor survival. Patients were assigned to one of three risk groups according to the cumulative risk defined as the sum of simplified risk scores of the four independent prognostic factors. Low-, intermediate- and high-risk patients achieved a median survival of 10.2 months (95% confidence interval (CI) 8.9-11.6), 5.1 months (95% CI 4.0-6.2) and 2.8 months (95% CI 0.5-5.2), respectively. The high-risk group encompassed PS 2 patients with two or three adjunctive unfavourable independent prognostic factors. CONCLUSIONS: Performance status, white blood cells count, histology and brain metastases resulted in our series prognostic factors of survival in NSCLC patients treated with chemotherapy at a multivariate analysis. Leukocyte count resulted the stronger factor after performance status. If prospectly validated, the proposed prognostic model could be useful to stratify performance status 2 patients in specific future trials.

Antiphospholipid antibodies in patients with cancer.

Antiphospholipid antibodies are generally associated with Antiphospholipid Syndrome, which can occur as a primary disorder or may be secondary to connective tissue disease or tumour. The presence of antiphospholipid antibodies in patients with tumour disease is responsible for thrombotic complications. In a population of 53 tumor patients with positive carcinoembryonic antigen CEA, carbohydrate antigen CA19.9, CA125 and CA15.3 markers, IgM and IgG anticardiolipin and antiphosphatidylinositol were detected by solid-phase immunoassays. Our results show that moderate or high levels of antiphospholipid antibodies are present in a great number of patients with CEA and CA19.9 markers, suggesting a specific association with gastroenteric tumors. By testing for antiphosphatidylinositol antibodies, many patients not evidenced by the standard anticardiolipin assay were found to be antiphospholipid-positive. The analysis of antiphosphatidylinositol antibodies as a diagnostic tool in gastroenteric cancer to highlight patients with the risk of thromboembolic complications is discussed.

Low levels of serum cholesterol/phospholipids are associated with the antiphospholipid antibodies in monoclonal gammopathy.

A decrease in cholesterol blood level, not due to a decrease synthesis by the liver, has been observed in patients suffering from tumors. In this work cholesterol blood was evaluated in patients affected by monoclonal gammopathy who were not subjected to any treatment. The blood of 25 patients were analyzed for protein and lipid content. Patients were divided according to the gamma protein content into three groups, and it was demonstrated that the group with high levels of gamma proteins presented a strong decrease in blood cholesterol and phospholipids. In these patients the presence of antibodies against phospholipids by using cardiolipin and phosphatidylinositol as antigens has also been demonstrated. The antibodies were rare in patients with a low content of gamma proteins and normal level of lipids, but the frequency was more than 80% in patients with low blood lipid levels.

Prolonged gemcitabine infusion in advanced non-small-cell lung cancer with stable disease after gemcitabine 30-min infusion.

BACKGROUND: Although 30-min gemcitabine infusion has become the standard administration, pre-clinical and clinical studies have suggested the possibility that an infusion rate of 10 mg/m(2) per minute may be more effective. The main objective of this study was to investigate whether the pursuance of gemcitabine, administered at a prolonged infusion rate, was able to convert stable disease to objective response after two or three cycle of standard administration. The secondary end-point was the evaluation of the new schedule toxicity. PATIENTS AND METHODS: Thirty-eight patients, with stage IIIA-B and IV NSCLC already treated by two or three cycles of 30-min gemcitabine infusion, alone or in combination with cisplatin, were enrolled: 26 patients (aged <70 years) were treated with cisplatin 80 mg/m(2) on day 1 plus gemcitabine 1200 mg/m(2) over 120 min on day 1 and 8 every three weeks and 12 patients (aged > or =70 years) were treated with gemcitabine alone 1200 mg/m(2) over 120 min on day 1 and 8 every three weeks, for two courses. Simon's two stage minimax design was applied to calculate the sample size. Assuming p(0) (low conversion rate) 5%, p(1) (target conversion rate of interest) 20%, alpha error 0.05, beta error 0.10 a total of 29 evaluable patients had to be accrued during stage 1. In case at least one objective response was observed, a further nine evaluable patients had to be enrolled into the study during stage 2. The regimen was considered promising if > or =4 objective responses out of 38 evaluable patients were observed. RESULTS: Thirty-eight patients were evaluable for response and in five patients (with stable disease after two courses of gemcitabine 30' infusion) a partial response was observed (conversion rate 13.1%, 95% confidence interval 4.4-28%). Toxicities were more frequently observed with cisplatin plus 120-min gemcitabine infusion: grade 3-4 neutropenia, thrombocytopenia and anaemia in 28, 22 and 16% of the courses, respectively. CONCLUSIONS: The prolongation of gemcitabine infusion time is able to convert stable disease to partial response in 13% of the cases. The haematological toxicity seems enhanced with cisplatin plus gemcitabine prolonged infusion.

Increased dose-intensity of gemcitabine in advanced non small cell lung cancer (NSCLC): a multicenter phase II study in elderly patients from the "polmone toscano group" (POLTO).

Gemcitabine is usually administered at a planned dose-intensity (DI) from 750 to 800 mg/m2/week. Preclinical data have suggested a possible dose-response relationship of gemcitabine. A multicenter phase II study was conducted to evaluate the activity in terms of no progression rate (complete responses+partial responses+stable diseases) of gemcitabine administered at an increased DI (1000 mg/m2/week) in elderly advanced non-small-cell lung cancer (NSCLC) patients. Secondary endpoints were to evaluate tolerability, progression free survival and overall survival. Elderly (age>or=70 years) chemo-naive advanced NSCLC patients, ECOG PS 0-2, were treated with intravenous gemcitabine 1500 mg/m2 intravenous (30 min infusion) on days 1 and 8 every 21 days for four courses. One hundred and twenty-two patients with a median age of 75 years (range 70-84) entered the study. The following grade 3 (NCI-CTC) haematological toxicities were reported (percent of patients): neutropenia 2.4%, thrombocytopenia 1.6%, anaemia 2.4%. No grades 3-4 non-haematological toxicities were observed. Among 111 evaluable patients 52 (46.8%) no progressions, 17 (15.3%) partial responses (WHO criteria), 35 (31.5%) stable diseases and 59 (53.2%) progressions were observed. Median time to progression was 3.2 months and median duration of survival was 5.4 months. The overall 1-year survival rate was 27%. Although increased dose-intensity of gemcitabine in elderly NSCLC patients is feasible without severe toxicities, this does not seem to be associated with an increased activity and efficacy in comparison to standard gemcitabine regimens with lower dose-intensities.

CTNS mutations in African American patients with cystinosis.

Cystinosis, an autosomal recessive lysosomal storage disorder, is rarely diagnosed in African Americans. The disease results from mutations in the gene CTNS; at least 55 such mutations have been reported. By far the most common is a 57,257-bp deletion of Northern European origin encompassing most of the CTNS gene. We performed mutation analysis on DNA from four African American patients with cystinosis. In one individual with classical, nephropathic cystinosis, we identified a new molecular defect, i.e., a homozygous GT-->CC substitution at the +5 position of IVS 5 of CTNS (IVS 5+5 GT-->CC). The out-of-frame splicing of exon 5 creates a null allele consistent with the patient's severe phenotype. Two patients were heterozygous and one homozygous for the common 57-kb deletion allele, reflecting the admixture of African and Northern European gene pools in North America. The two African Americans heterozygous for the 57-kb deletion were also hemizygous for a 928G-->A change, associated with ocular or nonnephropathic cystinosis. These two individuals are the only known African Americans with ocular cystinosis. We conclude that the diagnosis of cystinosis should be entertained in African Americans with symptoms of the disease, and that mutation analysis for the 57-kb deletion should be considered in this group of patients.

Ocular nonnephropathic cystinosis: clinical, biochemical, and molecular correlations.

Ocular nonnephropathic cystinosis, a variant of the classic nephropathic type of cystinosis, is an autosomal recessive lysosomal storage disorder characterized by photophobia due to corneal cystine crystals but absence of renal disease. We determined the molecular basis for ocular cystinosis in four individuals. All had mutations in the cystinosis gene CTNS, indicating that ocular cystinosis is allelic with classic nephropathic cystinosis. The ocular cystinosis patients each had one severe mutation and one mild mutation, the latter consisting of either a 928 G-->A (G197R) mutation or an IVS10-3 C-->G splicing mutation resulting in the insertion of 182 bp of IVS10 into the CTNS mRNA. The mild mutations appear to allow for residual CTNS mRNA production, significant amounts of lysosomal cystine transport, and lower levels of cellular cystine compared with those in nephropathic cystinosis. The lack of kidney involvement in ocular cystinosis may be explained by two different mechanisms. On the one hand (e.g. the G197R mutation), significant residual cystinosin activity may be present in every tissue. On the other hand (e.g. the IVS 10-3 C-->G mutation), substantial cystinosin activity may exist in the kidney because of that tissue's specific expression of factors that promote splicing of a normal CTNS transcript. Each of these mechanisms could result in minimally reduced lysosomal cystine transport in the kidneys.

CTNS mutations in an American-based population of cystinosis patients.

Nephropathic cystinosis is an autosomal recessive lysosomal storage disease characterized by renal failure at 10 years of age and other systemic complications. The gene for cystinosis, CTNS, has 12 exons. Its 2.6-kb mRNA codes for a 367-amino-acid putative cystine transporter with seven transmembrane domains. Previously reported mutations include a 65-kb "European" deletion involving marker D17S829 and 11 small mutations. Mutation analysis of 108 American-based nephropathic cystinosis patients revealed that 48 patients (44%) were homozygous for the 65-kb deletion, 2 had a smaller major deletion, 11 were homozygous and 3 were heterozygous for 753G-->A (W138X), and 24 had 21 other mutations. In 20 patients (19%), no mutations were found. Of 82 alleles bearing the 65-kb deletion, 38 derived from Germany, 28 from the British Isles, and 4 from Iceland. Eighteen new mutations were identified, including the first reported missense mutations, two in-frame deletions, and mutations in patients of African American, Mexican, and Indian ancestry. CTNS mutations are spread throughout the leader sequence, transmembrane, and nontransmembrane regions. According to a cystinosis clinical severity score, homozygotes for the 65-kb deletion and for W138X have average disease, whereas mutations involving the first amino acids prior to transmembrane domains are associated with mild disease. By northern blot analysis, CTNS was not expressed in patients homozygous for the 65-kb deletion but was expressed in all 15 other patients tested. These data demonstrate the origins of CTNS mutations in America and provide a basis for possible molecular diagnosis in this population.

Three new mutations in a gene causing Hermansky-Pudlak syndrome: clinical correlations.

Hermansky-Pudlak syndrome (HPS) consists of oculocutaneous albinism, a platelet storage pool deficiency, and ceroid lipofuscinosis. HPS is common in northwest Puerto Rico, where affected individuals are homozygous for a 16-bp duplication in the gene HPS. Two other homozygous frameshift mutations in HPS were previously identified among non-Puerto Rican patients. Eighteen non-Puerto Rican HPS families were studied and HPS mutations in three of them identified. One mutation, T322insC, has been previously described. However, three additional mutations, E133X, T322delC, and S396delC, have not been reported. Two families exhibited compound heterozygosity for these mutations, although most previously reported HPS patients have been homozygous for a particular mutation. All the newly described mutations were associated with decreased or undetectable levels of HPS RNA by Northern blot analysis of fibroblasts, and all had significant pigment dilution. To date, all mutations in HPS result in a truncated protein, suggesting that the C-terminal portion of the HPS protein is functionally important.

Genetic defects and clinical characteristics of patients with a form of oculocutaneous albinism (Hermansky-Pudlak syndrome).

BACKGROUND: Hermansky-Pudlak syndrome is characterized by oculocutaneous albinism, a storage-pool deficiency, and lysosomal accumulation of ceroid lipofuscin, which causes pulmonary fibrosis and granulomatous colitis in some cases. All identified affected patients in northwest Puerto Rico are homozygous for a 16-bp duplication in exon 15 of a recently cloned gene, HPS. We compared the clinical and laboratory characteristics of these patients with those of patients without the 16-bp duplication. METHODS: Forty-nine patients -- 27 Puerto Ricans and 22 patients from the mainland United States who were not of Puerto Rican descent -- were given a diagnosis on the basis of albinism and the absence of platelet dense bodies. We used the polymerase chain reaction to determine which patients carried the 16-bp duplication. RESULTS: Twenty-five of the Puerto Rican patients were homozygous for the 16-bp duplication, whereas none of the non-Puerto Rican patients carried this mutation. Like the patients without the duplication, the patients with the 16-bp duplication had a broad variation in pigmentation. Nine of 16 adults with the duplication, but none of the 10 without it, had a diffusing capacity for carbon monoxide that was less than 80 percent of the predicted value. High-resolution computed tomography in 12 patients with the 16-bp duplication revealed minimal fibrosis in 8, moderate fibrosis in 1, severe fibrosis in 1, and no fibrosis in 2. Computed tomography in eight patients without the duplication revealed minimal fibrosis in three and no fibrosis in the rest. Inflammatory bowel disease developed in eight patients (four in each group) between 3 and 25 years of age. CONCLUSIONS: The 16-bp duplication in exon 15 of HPS, which we found only in Puerto Rican patients, is associated with a broad range of pigmentation and an increased risk of restrictive lung disease in adults.

Normal brain myelination in a patient homozygous for a mutation that encodes a severely truncated methionine adenosyltransferase I/III.

Two isozymes of mammalian methionine adenosyltransferase, MAT I and MAT III, are expressed solely in adult liver. They are, respectively, tetramers and dimers of a single subunit encoded by the gene MAT1A. A third isozyme, MAT II, contains a catalytic subunit encoded by a separate gene, MAT2A, and is expressed in a variety of tissues, including (to a slight extent) adult liver. Based on a recent finding that 2 children with isolated hypermethioninemia and brain demyelination were homozygous for MAT1A mutations predicted to produce severely truncated proteins, and devoid of activity when expressed, it was concluded that complete lack of MAT I/III activity may be associated with neurological symptoms and demyelination. We now report that a 43-year-old man with persistent isolated hypermethioninemia, previously demonstrated to have deficient MAT activity in his liver, has normal brain myelination on MRI and normal neurological function, despite being homozygous for a 539 TG insertion in exon V of MAT1A, so that the gene is predicted to encode a protein of only 184 rather than the normal 395 amino acids. This patient's exon V mutation was demonstrated by SSCP analysis and verified by sequencing. Both parents are heterozygous for the same insertion. This suggests that MAT1A mutations producing severely truncated proteins do not necessarily produce brain demyelination. This finding has relevance to a previously reported 4-year-old girl who was also homozygous for the 539insTG mutation. Finally, our patient's 7% residual hepatic MAT activity, measured at 1 mM methionine, may reflect the hepatic activity of the more ubiquitous enzyme form, MAT II.

Characterization of a melanosomal transport system in murine melanocytes mediating entry of the melanogenic substrate tyrosine.

In this study, we identify a transport system for tyrosine, the initial precursor of melanin synthesis, in the melanosomes of murine melanocytes. Melanosomes preloaded with tyrosine demonstrated countertransport of 10 microM [3H]tyrosine, indicating carrier-mediated transport. Melanosomal tyrosine transport was saturable, with an apparent Km for tyrosine transport of 54 microM and a maximal velocity of 15 pmol of tyrosine/unit of hexosaminidase/min. Transport was temperature-dependent (Ea = 7.5 kcal/mol) and showed stereospecificity for the l-isomer of tyrosine. Aromatic, neutral hydrophobic compounds (such as tryptophan and phenylalanine), as well as the small, bulky neutral amino acids (such as leucine, isoleucine, and methionine) competed for tyrosine transport. Tyrosine transport was inhibited by the classical system L analogue, 2-aminobicyclo[2.2.1]heptane-2-carboxylic acid and by monoiodotyrosine, but not by cystine, lysine, glutamic acid, or 2-(methylamino)-isobutyric acid. Tyrosine transport showed no dependence on Na+ or K+, and did not require an acidic environment or the availability of free thiols. These results demonstrate the existence of a neutral amino acid carrier in murine melanocyte melanosomes which resembles the rat thyroid FRTL-5 lysosomal system h. This transport system is critical to the function of the melanosome since tyrosine is the essential substrate required for the synthesis of the pigment melanin.

Intravenous cysteamine therapy for nephropathic cystinosis.

A 4-y-old boy with nephropathic cystinosis and gastrointestinal dysmotility of unknown etiology was treated with i.v. cysteamine over a period of 10 mo. Thirty minutes after a dose of 10 mg/kg cysteamine free base, the leukocyte cystine value had fallen from 11.9 to 4.9 nmol of half-cystine/mg of protein. When cysteamine was given every 6 h, the leukocyte cystine concentration, measured 5-7 h after a dose, decreased with increasing cysteamine doses up to 17 mg/kg; at this dose the cystine value was 1.1 nmol of half-cystine/mg of protein, or 9% of the untreated value. Oral administration of approximately 16 mg/kg per dose every 6 h to this patient over the previous 3 y achieved similar leukocyte cystine depletion, to 1.2 nmol of half-cystine/mg of protein. The plasma cysteamine concentration 30 min after a dose of 10 mg/kg was 71 microM; 5-7 h after a dose of up to 20 mg/kg, the concentration was below 5 microM. Dimethylsulfide was elevated in the breath and urine of this boy after, but not before, the initiation of i.v. cysteamine therapy. Ten months after the start of therapy, the patient tolerated 250 mg (14 mg/kg) every 8 h. Adverse effects of this treatment included lethargy and increased nausea and vomiting when a schedule of therapy every 6 h was attempted. This investigation demonstrates that cysteamine given through a central venous catheter is effective in reducing leukocyte cystine levels.