Cryopreservation of quince (Cydonia oblonga Mill.)

BACKGROUND

Quince (Cydonia oblonga Mill.) has great potential for utilisation in pharmaceutical and food industries.

OBJECTIVE

The study was to develop an efficient cryopreservation approach for quince.

METHODS

Factors on the survival and regrowth such as cold acclimation, explant type and recovery media composition were assessed. The effectiveness of the resultant protocols for a number of quince cultivars was determined.

RESULTS AND CONCLUSION

Quince shoot tips and nodal sections are successfully cryopreserved. Sustained regrowth of quince Angers A was observed after encapsulation-osmoprotection/dehydration, encapsulation-dehydration and PVS2 vitrification. The highest regrowth rate (80%) was obtained from explants excised from cold hardened shoots and cryopreserved using encapsulation-osmoprotection/dehydration and vitrification protocols. The optimised vitrification protocol in combination with shoot cold hardening and a MS recovery medium without activated charcoal and auxin resulted in satisfactory regrowth of shoots from six quince cultivars. The morphology of acclimatised plants derived from cryopreserved shoots was comparable with non-cryopreserved plants.

Cryopreservation of redwood (Sequoia sempervirens) in vitro buds using vitrification-based techniques

In this study, the efficiency of three vitrification-based cryopreservation techniques, i.e. vitrification, encapsulation-vitrification and droplet-vitrification were compared for cryopreserving Sequoia sempervirens apical and basal buds sampled from in vitro shoot cultures. The effect of cold-hardening of mother-plants and of bud culture medium and sucrose preculture was also investigated. Culture of apical and basal buds sampled from cold-hardened mother-plants on Quoirin and Lepoivre medium with activated charcoal had a positive effect on regrowth. Only droplet-vitrification ensured survival and regrowth after cryopreservation. After cryopreservation, regeneration of apical buds was possible for PVS2 exposure durations between 90 and 180 min but it remained low, with a maximum of 18 percent after 135 min treatment. With basal buds, regeneration after cryopreservation was possible over a larger range of PVS2 treatment durations, between 30 and 180 min. The highest regeneration percentage was slightly higher (22 percent) than that measured with apical buds, and was also achieved after 135 min PVS2 exposure.

Acute and selective regulation of glyceroneogenesis and cytosolic phosphoenolpyruvate carboxykinase in adipose tissue by thiazolidinediones in type 2 diabetes

AIMS/HYPOTHESIS

Regulation of glyceroneogenesis and its key enzyme cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C) plays a major role in the control of fatty acid release from adipose tissue. Here we investigate the effect of rosiglitazone on the expression of genes involved in fatty acid metabolism and the resulting metabolic consequences.

MATERIALS AND METHODS

Rosiglitazone was administered to Zucker fa/fa rats for 4 days and to 24 diabetic patients for 12 weeks, then mRNA expression for the genes encoding PEPCK-C, mitochondrial PEPCK, adipocyte lipid-binding protein, glycerol kinase, lipoprotein lipase and glycerol-3-phosphate dehydrogenase was examined in s.c. adipose tissue by real-time RT-PCR. Glyceroneogenesis was determined using [1-(14)C]pyruvate incorporation into lipids. Cultured adipose tissue explants from overweight women undergoing plastic surgery were incubated with rosiglitazone for various times before mRNA determination and analysis of PEPCK-C protein, activity and glyceroneogenesis.

RESULTS

Rosiglitazone administration to rats induced the expression of the gene encoding PEPCK-C mRNA (PCK1) and PEPCK-C activity in adipose tissue with a resulting 2.5-fold increase in glyceroneogenesis. This was accompanied by an improvement in dyslipidaemia as demonstrated by the decrease in plasma NEFAs and triacylglycerol. In rosiglitazone-treated diabetic patients, PCK1 mRNA was raised 2.5-fold in s.c. adipose tissue. Rosiglitazone treatment of adipose tissue explants from overweight women caused a selective augmentation in PCK1 mRNA which reached a maximum of 9-fold at 14 h, while mRNA for other genes remained unaffected. Experiments with inhibitors showed a direct and transcription-only effect, which was followed by an increase in PEPCK-C protein, enzyme activity and glyceroneogenesis.

CONCLUSIONS/INTERPRETATION

These results favour adipocyte glyceroneogenesis as the initial thiazolidinedione-responsive pathway leading to improvement in dyslipidaemia.

A novel Y243S mutation in the pyruvate dehydrogenase El alpha gene subunit: correlation with thiamine pyrophosphate interaction

We identified a new Y243S mutation in the X-linked E1 alpha-PDH gene in a patient with pyruvate dehydrogenase complex (PDHc) deficiency. The activity in cultured fibroblasts was very low even in the presence of high thiamine pyrophosphate (TPP) concentrations, indicating that the defect could be due to decreased affinity of PDHc for TPP.

Hyperinsulinism and hyperammonemia syndrome: report of twelve unrelated patients

Hyperinsulinism and hyperammonemia syndrome has been reported as a cause of moderately severe hyperinsulinism with diffuse involvement of the pancreas. The disorder is caused by gain of function mutations in the GLUD1 gene, resulting in a decreased inhibitory effect of guanosine triphosphate on the glutamate dehydrogenase (GDH) enzyme. Twelve unrelated patients (six males, six females) with hyperinsulinism and hyperammonemia syndrome have been investigated. The phenotypes were clinically heterogeneous, with neonatal and infancy-onset hypoglycemia and variable responsiveness to medical (diazoxide) and dietary (leucine-restricted diet) treatment. Hyperammonemia (90-200 micromol/L, normal <50 micromol/L) was constant and not influenced by oral protein, by protein- and leucine-restricted diet, or by sodium benzoate or N-carbamylglutamate administration. The patients had mean basal GDH activity (18.3 +/- 0.9 nmol/min/mg protein) not different from controls (17.9 +/- 1.8 nmol/min/mg protein) in cultured lymphoblasts. The sensitivity of GDH activity to inhibition by guanosine triphosphate was reduced in all patient lymphoblast cultures (IC(50), or concentrations required for 50% inhibition of GDH activity, ranging from 140 to 580 nM, compared with control IC(50) value of 83 +/- 1.0 nmol/L). The allosteric effect of ADP was within the normal range. The activating effect of leucine on GDH activity varied among the patients, with a significant decrease of sensitivity that was correlated with the negative clinical response to a leucine-restricted diet in plasma glucose levels in four patients. Molecular studies were performed in 11 patients. Heterozygous mutations were localized in the antenna region (four patients in exon 11, two patients in exon 12) as well as in the guanosine triphosphate binding site (two patients in exon 6, two patients in exon 7) of the GLUD1 gene. No mutation has been found in one patient after sequencing the exons 5-13 of the gene.

Characterization of an in vivo hormonally regulated phosphodiesterase 3 (PDE3) associated with a liver Golgi-endosomal fraction

The biochemical properties of an in vivo hormonally regulated low Km cAMP phosphodiesterase (PDE) activity associated with a liver Golgi-endosomal (GE) fraction have been characterized. DEAE-Sephacel chromatography of a GE fraction solubilized by a lysosomal extract resulted in the sequential elution of three peaks of activity (numbered I, II, and III), while ion-exchange HPLC resolved five peaks of activity (numbered 1, 2, 3, 4, and 5). Based on the sensitivity of the eluted activity to cGMP and selected phosphodiesterase inhibitors, two phosphodiesterase isoforms were resolved: a cGMP-stimulated and EHNA-inhibited PDE2, eluted in DEAE-Sephacel peak I and HPLC peak 2 and a cGMP-, a cilostamide-, and ICI 118233-inhibited PDE3, eluted in DEAE-Sephacel peak III and HPLC peaks 3, 4, and 5. GE fractions isolated after acute treatments with insulin, tetraiodoglucagon, and growth hormone displayed an increase in phosphodiesterase activity relative to saline-injected controls, as did GE fractions from genetically obese and hyperinsulinemic rats relative to lean littermates. In all experimental rats, an increase in PDE3 activity associated with DEAE-Sephacel peak III and HPLC peaks 4 and 5 was observed relative to control animals. Furthermore, in genetically obese Zucker rats, an increase in the sensitivity of PDE activity to cilostamide and in the amount of PDE activity immunoprecipitated by an antibody to adipose tissue PDE3 was observed relative to lean littermates. These results extend earlier studies on isolated hepatocytes and show that liver PDE3 is the main if not sole PDE isoform activated by insulin, glucagon, and growth hormone in vivo.

New splicing-site mutations in the SURF1 gene in Leigh syndrome patients

The gene SURF1 encodes a factor involved in the biogenesis of cytochrome c oxidase, the last complex in the respiratory chain. Mutations of the SURF1 gene result in Leigh syndrome and severe cytochrome c oxidase deficiency. Analysis of seven unrelated patients with cytochrome c oxidase deficiency and typical Leigh syndrome revealed different SURF1 mutations in four of them. Only these four cases had associated demyelinating neuropathy. Three mutations were novel splicing-site mutations that lead to the excision of exon 6. Two different novel heterozygous mutations were found at the same guanine residue at the donor splice site of intron 6; one was a deletion, whereas the other was a transition [588+1G>A]. The third novel splicing-site mutation was a homozygous [516-2_516-1delAG] in intron 5. One patient only had a homozygous polymorphism in the middle of the intron 8 [835+25C>T]. Western blot analysis showed that Surf1 protein was absent in all four patients harboring mutations. Our studies confirm that the SURF1 gene is an important nuclear gene involved in the cytochrome c oxidase deficiency. We also show that Surf1 protein is not implicated in the assembly of other respiratory chain complexes or the pyruvate dehydrogenase complex.

Reproducibility of the clinical criteria (ABCDE rule) and dermatoscopic features (7FFM) for the diagnosis of malignant melanoma

Dermatoscopy improves the sensitivity and the specificity in the diagnosis of melanoma. Although the reproducibility of dermatoscopic features has been the subject of research, no study up to now has compared the reproducibility of dermatoscopic features to the reproducibility of the clinical criteria of the ABCDE rule. For this reason we decided to examine the reproducibility of the clinical ABCDE rule and of our diagnostic dermatoscopic method 7FFM, as well as of the individual criteria of both. A total of 73 dermatologists attended three dermatoscopic courses and examined a set of clinical and dermatoscopic slides of 50 pigmented skin tumors. Agreement % and K value for a kappa statistical analysis have been calculated to evaluate inter-rater reliability. The clinical and the dermatoscopic methods showed similar values of concordance: clinical score 2 mean agreement = 68%, mean K = 0.44; clinical score 3 mean agreement = 73%, mean K = 0.61; 7FFM mean agreement = 83%, mean K = 0.64. The clinical criteria A, B, and C and the dermatoscopic features of our method presented similar values of concordance as well: clinical criteria mean K range 0.35-0.25, dermatoscopic features mean K range 0.62-0.25. The dermatoscopic features of our method 7FFM show a good reproducibility after a short training program, similar to the reproducibility of the clinical criteria of the ABCDE rule for the diagnosis of melanoma.

Effects of growth hormone on growth factors after renal transplantation

Growth retardation occurs frequently in renal transplanted children (RTx) and can be improved by growth hormone (GH) treatment. This study retrospectively examines the insulin-like growth factor-1 (IGF-1) and IGF binding protein (IGFBP) profile of ten growth-retarded children previously given renal allografts, after 1 year of GH treatment period. Ten prepubertal patients (nine boys and one girl) were investigated. They had a mean chronological age (CA) of 11.4 +/- 1.1 years and a mean bone age (BA) of 7.3 +/- 0.9 years. Mean height was -3.9 +/- 0.4 SD units below the mean for CA. The mean body mass index (BMI) was 16.9 +/- 0.6 and the mean inulin clearance was 36.5 +/- 4.9 ml/min/1.73 m2. Recombinant hGH was given at 4 IU/m2/day. Plasma GH, total and free IGF-1, IGFBP-2 and -3 were measured by specific radioimmunoassay (RIA). IGFBPs were characterized by SDS PAGE techniques and ligand and immunoblot analyses. Mean velocity was markedly increased (P < 0.01) after 1 year of GH therapy, expressed as SD score for BA. The range of growth response was wide. The total and free plasma IGF-1 increased (P < 0.01) by about 100% (mean values after GH therapy: 95.9 +/- 2.1 nM and 165 +/- 29 pM, respectively). Plasma IGFBP-3 concentrations increased by about 40% (mean value: 148 +/- 18 pM, P < 0.01), with a concomitant increase in both intact IGFBP-3 and its 30-kDa proteolytic fragment. There was no change in plasma IGFBP-2 concentration. Both mean values of inulin clearance and BMI were unchanged during the treatment. In view of the IGF-1/IGFBP concentration changes, there should have been an even better growth response to GH therapy in these patients. This strongly suggests IGF-1 insensitivity, probably as a result of corticosteroid therapy.

Development of a shoot-tip vitrification protocol and comparison with encapsulation-based procedures for plum (Prunus domestica L.) cryopreservation

Cryopreservation of plum (Prunus domestica L.), cv Regina Claudia, was obtained by a vitrification/one-step cooling procedure of shoot tips from cold-hardened in vitro-grown plants. Best survival (57%) was obtained when the shoot tips were precultured at 4 degree C for 2 days on 0.09 M sucrose-containing Quoirin and Le Poivre medium, loaded for 30 min with a cryoprotectant (2 M glycerol and 0.4 M sucrose), incubated with the PVS2 solution at 0 C for 90 min, and directly plunged into liquid nitrogen. After re-warming in a waterbath at 40 degree C, the shoot tips were washed in a 1.2 M-sucrose MS solution for 20 min and finally plated on a regrowth medium. In comparison with the one-step cooling procedure, both the slow cooling (-0.5 degree C/min up to -45 degree C), and the two-step cooling (-160 degree C for 25 min, then -196 degree C) gave lower percentages of shoot-tip survival. Among the other cryogenic procedures tested, the performance of the encapsulation-vitrification method was similar to the vitrification protocol in terms of shoot-tip regrowth (47.5%), while encapsulation-dehydration was unsatisfactory.

A family of polynuclear cobalt and nickel complexes stabilised by 2-pyridonate and carboxylate ligands

The synthesis and structural characterisation of a series of cobalt and nickel cages are reported. Eight of these structures contain a [M10(mu3-OH)6(eta2, mu3-xhp),(eta2, mu2-O2CR)6]2+ core (where M = Co or Ni; xhp = 6-chloro- or 6-methyl-2-pyridonate: R = Me, Ph, CHMe2, CH2Cl, CHPh2 or CMe3), where the ten metal atoms describe a centred-tricapped-trigonal prism (ttp). The cage contains six hydroxide ligands around the central metal, and the exterior is coated with pyridonate and carboxylate ligands. For four of the cages additional metal centres are found attached to the upper and/or lower triangular faces of the trigonal prism, generating dodeca- and undecanuclear cages. Three further cages are reported that contain a metal core based on an incomplete centred-tetraicosahedron. These cages involve trimethylacetate as a ligand in company with either 6-methyl-2-pyridonate or 6-chloro-2-pyridonate. Comparison of these latter structures with the trigonal prisms reveal that they can be described as a pentacapped-trigonal prism missing one edge. Magnetic studies of three of the nickel cages with trigonal prismatic cores show spin ground states of S = 8, 4 and 2 for Ni12, Ni11 and Ni10 cages, respectively.

Reproducibility of a dermoscopic method (7FFM) for the diagnosis of malignant melanoma

Dermoscopy improves sensitivity in the diagnosis of melanoma. We have developed a new diagnostic dermoscopic method which evaluates only seven dermoscopic features or criteria. We called the method Seven features for melanoma (7FFM). To present and to evaluate the reproducibility of our dermoscopic diagnostic method (7FFM) we held eight dermoscopic courses from 10/4/96 to 04/03/98 in various Italian cities. In fact the reliability of a diagnostic test or method mainly depends on the level of agreement in the interpretation of results among different observers. Only methods with good agreement can be used in clinical practice for the diagnosis of melanoma. Many dermatologists (207) attended one of the eight dermoscopic courses: each course was one-day in length and at the end of the course the participants evaluated a set of 25 dermoscopic slides using our dermoscopic method. Percentages of concordance and K values for a kappa statistical analysis to evaluate inter-rater reliability have been calculated. The method showed a mean percentage of concordance of 85.7%, median 88%, a mean K value of 0.699, median 0.684. These data point to a good agreement level. Our method shows good reproducibility after a short training program.

First prenatal diagnosis of defects in the HsPDX1 gene encoding protein X, an additional lipoyl-containing subunit of the human pyruvate dehydrogenase complex

We have previously reported a genetic study of a neonatal lactic acidosis linked to a pyruvate dehydrogenase complex deficiency due to the absence of the protein X subunit. This rare autosomal recessive disorder is associated with specific deletions in this polypeptide which is encoded by the HsPDX1 gene, located on chromosome 11p1.3. The pathology of the patient was considered to arise from a large homozygous deletion (78del85) found at the 5' end of the HsPDX1 coding sequence. Her heterozygous mother underwent prenatal diagnosis during a subsequent pregnancy. Chorionic villus samples were used for three independent studies: (1) normal levels of the protein X component of the PDH complex were detected by immunoblotting; (2) RT-PCR analysis showed no deletion at the 5' end of the cDNA but the presence of a distinct heterozygous deletion (965del59) at its 3' end inherited from the father; (3) haplotype analysis revealed the presence of the father's mutated allele and the mother's normal allele. It was concluded that the fetus was heterozygous for this separate 3' deletion, so, it was likely to be not affected. This study permitted us to characterize more precisely the genetic abnormalities of the HsPDX1 cDNA occurring in each family's member.

The dermoscopic versus the clinical diagnosis of melanoma

Dermoscopy is an useful technique for the diagnosis of melanoma. All the diagnostic dermoscopic methods developed until now have been tested on dermoscopic slides and the real improvement given by this technique to the clinical diagnosis based upon ABCDE criteria is still unknown. For this reason, we decided to undertake a prospective study to compare the clinical diagnosis made with ABCDE criteria, to the dermoscopic diagnosis, made with the method 7FFM, developed by us. A total of 401 lesions were evaluated clinically and dermoscopically. On the basis of the number of the clinical criteria considered sufficient to diagnose a melanoma, various clinical scores, ranging from 1 to 5, can be obtained; data about the sensitivity of the clinical diagnosis of melanoma suggest that the most often used score is score 3. Our method 7FFM presents a sensitivity and a specificity better than those obtained with score 3: 80% versus 66.6% and 89.1% versus 79.3%. Besides this, we have evaluated if the sensitivity of our method 7FFM in the diagnosis of melanoma can be improved with the adjunct of the clinical criteria or of the clinical scores. The best values of sensitivity 93.3% and predictive value negative 97.3% have been obtained with score 2 plus 7FFM. Our results confirm that our method can be used in the screening of pigmented skin lesions in daily office practice and that an improvement in sensitivity without an excessive sacrifice of specificity can be obtained with the adjunct of the clinical score 2.

The seven features for melanoma: a new dermoscopic algorithm for the diagnosis of malignant melanoma

The clinical diagnosis of melanoma has a mean sensitivity of 67%, dermoscopy or dermatoscopy is a non invasive technique which improves this sensitivity. Our purpose was to create a simple dermoscopic method for the diagnosis of melanoma useful in daily office practice. For this reason a training set of 218 cutaneous pigmented lesions was used and scored for 16 dermoscopic features: for each feature sensitivity, specificity and statistical significance were evaluated. The results were used to create a simple dermoscopic diagnostic method of only seven dermoscopic features (7FFM). The method was used to evaluate a test set of 713 pigmented skin lesions consecutively observed. The diagnostic dermoscopic method developed gave a sensitivity of 94.6%, a specificity of 85.5% and an efficiency of 87.6%. Our method improves the sensitivity in the diagnosis of melanoma and can be used for the screening of pigmented skin lesions.

Activation of a cGMP-stimulated cAMP phosphodiesterase by protein kinase C in a liver Golgi-endosomal fraction

The ability of Ca2+/phospholipid-dependent protein kinase (protein kinase C, PKC) to stimulate cAMP phosphodiesterase (PDE) activity in a liver Golgi-endosomal (GE) fraction was examined in vivo and in a cell-free system. Injection into rats of 4 beta-phorbol 12-myristate 13-acetate, a known activator of PKC, caused a rapid and marked increase in PKC activity (+325% at 10 min) in the GE fraction, along with an increase in the abundance of the PKC alpha-isoform as seen on Western immunoblots. Concurrently, 4 beta-phorbol 12-myristate 13-acetate treatment caused a time-dependent increase in cAMP PDE activity in the GE fraction (96% at 30 min). Addition of the catalytic subunit of protein kinase A (PKA) to GE fractions from control and 4 beta-phorbol 12-myristate 13-acetate-treated rats led to a comparable increase (130-150%) in PDE activity, suggesting that PKA is probably not involved in the in-vivo effect of 4 beta-phorbol 12-myristate 13-acetate. In contrast, addition of purified PKC increased (twofold) PDE activity in GE fractions from control rats but affected only slightly the activity in GE fractions from 4 beta-phorbol 12-myristate 13-acetate-treated rats. About 50% of the Triton-X-100-solubilized cAMP PDE activity in the GE fraction was immunoprecipitated with an anti-PDE3 antibody. On DEAE-Sephacel chromatography, three peaks of PDE were sequentially eluted: one early peak, which was stimulated by cGMP and inhibited by erythro-9 (2-hydroxy-3-nonyl) adenine (EHNA); a selective inhibitor of type 2 PDEs; and two retarded peaks of activity, which were potently inhibited by cGMP and cilostamide, an inhibitor of type 3 PDEs. Further characterization of peak I by HPLC resolved a major peak which was activated (threefold) by 5 microM cGMP and inhibited (87%) by 25 microM EHNA, and a minor peak which was insensitive to EHNA and cilostamide. 4 beta-Phorbol 12-myristate 13-acetate treatment caused a selective increase (2.5-fold) in the activity associated with DEAE-Sephacel peak I, without changing the K(m) value. These results suggest that PKC selectively activates a PDE2, cGMP-stimulated isoform in the GE fraction.

Calcipotriol ointment in nail psoriasis: a controlled double-blind comparison with betamethasone dipropionate and salicylic acid

This double-blind randomized study was designed to compare the efficacy and safety of calcipotriol ointment (50 microg/g) with betamethasone dipropionate (64 mg/g) and salicylic acid (0.03 g/g) ointment in the treatment of nail bed psoriasis. Fifty-eight patients applied the given drug to the affected nails twice a day for 3-5 months, depending on clinical response. Efficacy was assessed monthly on the basis of nail thickness, measured in millimetres. Photographs of the treated nails were taken at baseline, and after 3 and 5 months. Tolerability was assessed at 3 and 5 months. In patients with fingernail psoriasis, after 3 months of treatment subungual hyperkeratosis was reduced from 2.3 +/- 0.1 mm (mean +/- SEM) to 1.5 +/- 0.1 mm (-26.5%) in the calcipotriol group and from 2.3 +/- 0.1 mm to 1.6 +/- 0.1 mm (-30.4%) in the betamethasone dipropionate and salicylic acid group [not significant (NS) between treatments, analysis of variance (ANOVA)]. After 5 months, responders showed a 49.2% reduction in hyperkeratosis in the calcipotriol group (from 2.8 +/- 0.1 mm to 1.4 +/- 0.2 mm) and 51.7% (from 2.1 +/- 0.1 mm to 1.0 +/- 0.1 mm) in the betamethasone dipropionate and salicylic acid group (P < 0.001 from baseline, NS between treatments, ANOVA). In patients with toenail psoriasis, after 3 months of treatment there was an overall reduction in hyperkeratosis from 2.6 +/- 0.1 mm to 2.1 +/- 0.1 mm (-20.1%) in the calcipotriol group and from 3.0 +/- 0.1 mm to 2.3 +/- 0.1 mm (-22. 9%) in the betamethasone dipropionate and salicylic acid group (P < 0.001 from baseline, NS between treatments, ANOVA). By the end of the fifth month there was a 40.7% reduction in hyperkeratosis in the calcipotriol group (from 2.1 +/- 0.1 mm to 1.2 +/- 0.1 mm) and 51.9% in the betamethasone dipropionate and salicylic acid group (from 2.7 +/- 0.1 mm to 1.3 +/- 0.1 mm; P < 0.0001 from baseline, NS between treatments, ANOVA). The results of the study show that calcipotriol is as effective as a combination of a topical steroid with salicylic acid in the treatment of nail psoriasis and represents a safe alternative in the topical treatment of nail psoriasis.