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Biomedical subjects

A J de Jong

Publications and source records attributed to A J de Jong.

At least 19 recordsLinked to original sources

A tomato homologue of the human protein PIRIN is induced during programmed cell death.

Programmed cell death (PCD), with similarities to animal apoptosis, was induced in tomato suspension cells by the topoisomerase I inhibitor camptothecin. Previously, a differential display screening was performed to isolate genes differentially expressed during camptothecin-induced cell death. As a result, the new tomato gene Le-pirin was isolated, whose mRNA levels dramatically increase during camptothecin-induced PCD. Le-pirin mRNA accumulation is also observed when cell death is triggered by the mycotoxin fumonisin-B1, but not when the suspension cells are treated with stress-related compounds such as ethylene, methyl jasmonate or salicylic acid. The caspase inhibitor Z-Asp-CH2-DCB and the calcium channel blocker LaCl3 effectively delayed whereas ethylene greatly stimulated camptothecin-induced PCD and the accumulation of Le-pirin mRNA. The Le-pirin encoded protein shows 56% identity with the human protein PIRIN, a nuclear factor reported to interact with the human oncogene Bcl-3. Human PIRIN stabilizes the formation of quaternary complexes between Bcl-3, the anti-apoptotic transcription factor NF-kappaB and its DNA target sequences in vitro. The isolation of Le-pirin and its implication in plant PCD provides new clues on the role of putative NF-kappaB-associated pathways in plant defence mechanisms.

Amino Acid Sequence↗

Post-streptococcal reactive arthritis: a clinical and serological description, revealing its distinction from acute rheumatic fever.

OBJECTIVE: To follow-up prospectively patients with arthritis after infection with beta-haemolytic streptococci of Lancefield group A (beta HSA), with emphasis on clinical characteristics and serological features. We additionally investigated whether these patients, though often fulfilling the Jones' criteria for acute rheumatic fever (ARF), had a disease with clinical characteristics different from ARF. DESIGN: We performed a systematic prospective observational study of consecutive patients at a Dutch Outpatient Clinic and Department of Rheumatology, with arthritis after throat infection with beta HSA presenting to rheumatologist or internist from September 1992 until September 1996. Main outcome measures were clinical and biochemical characteristics with special reference to carditis. RESULTS: A total of 23 patients (21 Dutch, two Turkish; female/male ratio 15/8; mean (SD) age 42 (14) years) with predominantly non-migratory arthritis were included. A positive throat swab culture was obtained in 17%. All patients showed a significant rise of antistreptolysine-O (ASO; normal < 200 i.u. mL-1) and antideoxyribonuclease-B (anti-DNase-B; normal < 200 i.u. mL-1) titre. The mean (SEM) maximal ASO was 1305 (195) i.u. mL-1, and anti-DNase-B titre 980 (115) i.u. mL-1. Arthritis was present in mean (SEM) 5.4 (0.9) joints: 2.2 (0.7) small, 3.2 (0.4) larger joints. The arthritis was monarticular in 23% of the patients, oligoarticular in 35%, and polyarticular in 43%. Skin abnormalities were present in 12 patients: erythema nodosum in seven patients (30%), and erythema multiforme in five patients (22%). A transient cholestatic hepatitis was found in four patients (17%). In two patients a transient first-degree conduction block was found; however, neither echocardiography nor clinical course supported carditis. All patients were advised to receive monthly penicillin prophylaxis during a period of 2 years. Two patients refused to follow medical advice: in one a non-migratory arthritis recurred 15 months after the first episode of arthritis. CONCLUSION: Commonly, arthritis secondary to beta HSA infection in the Netherlands, a prosperous West-European country with State Welfare, is not accompanied by carditis, contrary to literature on classical ARF. Other factors discriminating it from ARF are the age of onset, the non-migratory character of the arthritis, the high frequency of erythema nodosum and multiforme, as well as the presence of transient hepatitis. As arthritis is the hallmark of this syndrome, post-streptococcal reactive arthritis (PSRA) is the most proper name for this disease entity. Whether penicillin profylaxis is needed in PSRA, as it is in ARF, warrants further prospective investigation.

Adult↗

A clinical and serological comparison of group A versus non-group A streptococcal reactive arthritis and throat culture negative cases of post-streptococcal reactive arthritis.

OBJECTIVE: To identify clinical and serological differences of patients with reactive arthritis after infection with Lancefield group A beta-haemolytic streptococci (GAS), compared with non-group A-that is, group C or G streptococci (NGAS:GCS/GGS), and a group of culture negative or unidentified streptococci (GUS). METHODS: A prospective study of consecutive patients with reactive arthritis after serologically or culture confirmed infection with beta-haemolytic streptococci, presenting to the outpatient department of rheumatology from January 1992 until January 1998. Alternative causes for reactive arthritis were excluded. Main outcome measures were clinical and serological characteristics including antistreptolysine-O (ASO) and antideoxyribonuclease-B (antiDNase-B) antibody titres. RESULTS: 41 patients (female/male ratio 22/19; mean (SD) age 38 (13) years) with reactive arthritis were included. Culture of throat swab was positive in 13 cases (32%): 6 (15%) GAS, 7 NGAS (17%), that is, 5 (12%) GCS, 2 (5%) GGS. In 28 cases throat culture remained negative resulting in a group of unidentified streptococci; antibiotic pre-treatment had been given by the general practitioner in 18 cases (64%). Arthritis was non-migratory, the number of arthritic joints in GAS and NGAS was similar, whereas in NGAS patients fewer joints were involved than in GUS: mean (SEM) 36 swollen joint index: 3.3 (1.0) in NGAS v 5.6 (1.0) in GUS (p<0.005); 28 swollen joint index: 2.9 (1.0) in NGAS v 4.3 (0.8) in GUS (p<0.05). Extra-articular manifestations-that is, erythema nodosum/ multiforme, AV conduction block or hepatitis-were observed after GAS or GUS infection, but not after NGAS infection. ASO and/or antiDNase-B rose significantly in all patients. The maximal titres for ASO and antiDNase-B in 41 PSRA patients were: mean (SEM) 1242 (232) U/l and 890 (100) U/l respectively; the maximal ASO titres were similar in the three groups: mean (SEM) 1125 (185) in GAS, 625 (160) in NGAS (GAS v NGAS: p=0.17), and 1430 (320) U/l in GUS (NGAS v GUS: p=0.10). AntiDNase-B titres were: mean (SEM) 1075 (180) in GAS, 375 (105) in NGAS (GAS v NGAS: p<0.01), and 995 (125) U/l in GUS (NGAS v GUS: p<0.005). ASO: antiDNase-B ratios were: mean (SEM) 0.89 (0.21) in GAS, 2.60 (0.76) in NGAS (GAS v NGAS: p<0.05), and 1.43 (0.28) in GUS (NGAS v GUS: p=0.12). CONCLUSION: Post-streptococcal reactive arthritis occurs not infrequently. Differentiation of PSRA based on the causative streptococcal strain is frequently thwarted by negative throat cultures. Sometimes extra-articular manifestations are present that exclude NGAS as the causative organism. Serologically, lower antiDNase-B titres may be indicative for primary NGAS infection; the ASO/antiDNase-B ratio may be of additive value for differentiation in cases of a negative throat culture: the higher ASO/antiDNase-B ratios suggesting primary NGAS infection. In reactive arthritis, serological monitoring consisting of a simultaneous titration of antiDNase-B and ASO, seems to be of clinical importance to trace GAS induced cases, especially when throat cultures remain negative.

Adult↗

The ipiO gene of Phytophthora infestans is highly expressed in invading hyphae during infection.

The expression of the in planta-induced gene ipiO of the potato late blight pathogen Phytophthora infestans was analyzed during various developmental stages of its life cycle. ipiO mRNA was detected in zoospores, cysts, germinating cysts, and young mycelia, but not in sporangia or in old mycelia grown in vitro. ipiO is not only expressed in stages prior to infection but also during colonization of potato and tomato leaves. In disease lesions, ipiO mRNA was detected in the water-soaked area and the healthy-looking plant tissue surrounding it. In contrast, ipiO mRNA was not found in necrotized tissue or in sporulating areas of a lesion. To determine more precisely the location and time of ipiO gene expression in planta, cytological assays were performed using a P. infestans transformant expressing a transcriptional fusion between the ipiO1 promoter and the beta-glucuronidase (GUS) reporter gene. GUS staining was found specifically in the subapical and vacuolated area of tips of invading hyphae. The histochemical GUS assays demonstrate that ipiO is expressed during biotrophic stages of the disease cycle.

Blotting, Northern↗

Reactive arthritis associated with group C and group G beta-hemolytic streptococci.

OBJECTIVE: Group A beta-hemolytic streptococci (GAS) are known to be capable of evoking sterile arthritis. Reactive arthritis (ReA) has been reported sporadically following primary infection with group C and group G beta-hemolytic streptococci (GCS, GGS). We prospectively studied 4 cases of ReA secondary to throat infection with GCS and GGS. METHODS: Four patients with arthritis secondary to throat infection were seen. Three patients were Dutch, one was Indonesian; female/male ratio was 1/3; mean age was 30 years (range 18-46). Diagnostic evaluation included culture of throat swab and serological screening. RESULTS: All patients presented with a nonmigratory asymmetrical arthritis: monoarthritis in one patient, oligoarthritis in 3. Culture of throat swab was positive in all. Antistreptolysin-O (ASO) titer rose significantly in 2 patients, and anti-DNase-B rose in 2 patients. ASO was maximal (mean 1000 U/ml; range 890-1110) and anti-DNase-B was 395 U/ml (range 290-500). Treatment consisted of feneticillin for 5 days; nonsteroidal antiinflammatory drugs were prescribed on demand. All patients recovered fully in 3 to 12 weeks. CONCLUSION: These cases provide evidence of a benign non-group A streptococcal ReA, i.e., secondary to GCS or GGS. The presence of the organism in the throat along with the elevation of antibody to streptococcal products is important for the diagnosis of GCS/GGS associated ReA. A positive throat culture is needed for differentiation from GAS associated poststreptococcal ReA, because prophylactic measures are effective only in GAS associated sequelae, but not in GCS/GGS associated ReA.

Adolescent↗

Combination of sulphasalazine and methotrexate versus the single components in early rheumatoid arthritis: a randomized, controlled, double-blind, 52 week clinical trial.

To compare the efficacy of sulphasalazine, methotrexate, and the combination of both in patients with early rheumatoid arthritis (RA), not treated with disease-modifying anti-rheumatic drugs previously, we conducted a double-blind, double-dummy, controlled, clinical trial. One hundred and five patients with active, early RA, rheumatoid factor and/or HLA DR1/4 positive were randomized between sulphasalazine (SSZ) 2000 (maximum 3000) mg daily, or methotrexate (MTX) 7.5 (maximum 15) mg weekly, or the combination (COMBI) of both, and were followed up by a single observer for 52 weeks. The mean change over time per patient, including all visits, in Disease Activity Score (DAS) was: SSZ: -1.6 (95% CI -2.0 to -1.2); MTX: -1.7 (-2.0 to -1.4); COMBI: -1.9 (-2.2 to -1.6); the difference week 0-week 52 (SSZ, MTX, COMBI respectively); DAS: -1.8, -2.0, -2.3, Ritchie articular index: -9.2, -9.5, -10.6, swollen joints: -9.2, -12.4, -14.3, erythrocyte sedimentation rate: -17, -21, -28. Nausea occurred significantly more in the COMBI group. The numbers of drop-outs due to toxicity were SSZ 9, MTX 2, COMBI 5. In conclusion, there were no significant differences in efficacy between combination and single therapy, only a modest trend favouring COMBI. The results of MTX and SSZ were very comparable. Nausea occurred more often in the COMBI group: the number of withdrawals due to adverse events did not differ significantly.

Adult↗

A gene encoding a protein elicitor of Phytophthora infestans is down-regulated during infection of potato.

Most species of the genus Phytophthora produce 10-kDa extracellular protein elicitors, collectively termed elicitins. Elicitins induce hypersensitive response in a restricted number of plants, particularly in the genus Nicotiana within the Solanaceae family. A cDNA encoding INF1, the major secreted elicitin of Phytophthora infestans, a pathogen of solanaceous plants, was isolated and characterized. The expression of the corresponding inf1 gene during the disease cycle of P. infestans was analyzed. inf1 was shown to be expressed in mycelium grown in various culture media, whereas it was not expressed in sporangiospores, zoospores, cysts, and germinating cysts. In planta, during infection of potato, particularly during the biotrophic stage, expression of inf1 was down-regulated compared to in vitro. The highest levels of expression of inf1 were observed in in vitro grown mycelium and in late stages of infection when profuse sporulation and leaf necrosis occur. The potential role of INF1 as an elicitor in interactions between P. infestans and Solanum species was investigated. Nineteen lines, representing nine solanaceous species with various levels of resistance to P. infestans, were tested for response to an Escherichia coli expressed INF1. Within the genus Solanum, resistance to P. infestans did not appear to be mediated by a defense response elicited by INF1. However, INF1 recognition could be a component of nonhost resistance of tobacco to P. infestans.

Algal Proteins↗

Characterization of chitinases able to rescue somatic embryos of the temperature-sensitive carrot variant ts 11.

To characterize the acidic endochitinase EP3, able to rescue somatic embryos of the carrot cell line ts11, the enzyme was purified from the medium of wild-type suspension cultures. Peptide sequences, deduced amino acid sequences of corresponding PCR-generated cDNA clones, serological relation and biochemical properties showed that there were at least five closely related chitinases, four of which could be identified as class IV EP3 chitinases with an apparent size of 30 kDa. Two other proteins were identified as a serologically related class I acidic chitinase (DcChitI) of 34 kDa, and a serologically unrelated 29 kDa class II acidic chitinase (DcChitII), respectively. Additional cDNA sequences, Western and Southern analysis showed the presence of a least two, but possibly more, highly homologous class IV EP3 genes in the carrot genome. Two class IV EP3 chitinases were tested and found to be able to increase the number of ts11 globular embryos formed under non-permissive conditions. One of the class IV EP3 chitinases as well as the class I chitinase DcChitI promoted the transition from globular to heart-stage ts11 embryos. The class II endochitinase and a heterologous class IV chitinase from sugar-beet were not active on ts11. This suggests that there are differences in the specificity of chitinases in terms of their effect on plant somatic embryos.

Amino Acid Sequence↗

Purification, immunological characterization and cDNA cloning of a 47 kDa glycoprotein secreted by carrot suspension cells.

A 47 kDa glycoprotein, termed EP4, was purified from carrot cell suspension culture medium. An antiserum raised against EP4 also recognized a protein of 45 kDa that was ionically bound to the cell wall. EP4 was detected in culture media from both embryogenic and non-embryogenic cell lines and was found to be secreted by a specific subset of non-embryogenic cells. Secretion of the 47 kDa glycoprotein by embryogenic cells was not evident. The 45 kDa cell wall-bound EP4 protein was specific for non-embryogenic cells and was shown by immunolocalization to occur in the walls of clustered cells, with the highest levels in the walls separating adjacent cells. In seedlings, EP4 proteins were mainly found in roots. EP4 cDNA was cloned by screening a cDNA library with an oligonucleotide derived from an EP4 peptide sequence. The EP4 cDNA sequence was found to be 55% homologous to ENOD8, an early nodulin gene from alfalfa.

Amino Acid Sequence↗

[Chronic recurrent polychondritis].

In a 71-year-old woman suffering from recurrent fever, dry cough, pain during sighing, hoarseness and later severe inflammation of the cartilage of both auricles 'relapsing polychondritis' was diagnosed. This is a rare disease of cartilage and connective tissue. Most frequent symptoms are inflammation of the auricles and nasal septum, joint disorders and inflammation of eye structures, larynx and trachea. The aetiology may be autoimmunity. The clinical diagnosis can be confirmed by a cartilage biopsy. The disease is recurrent and causes substantial morbidity and mortality. Therapy consists of NSAIDs, steroids, and sometimes immunosuppressive agents.

Aged↗

Signal molecules involved in plant embryogenesis.

In plant embryogenesis, inductive interactions mediated by diffusable signal molecules are most likely of great importance. Evidence has been presented that at late globular stages in plant embryogenesis, perturbation of the polar auxin transport results in abberrant embryo morphology. Rhizobium lipooligosaccharides or Nod factors are a newly discovered class of bacterial molecules that are able to trigger initial steps in root nodule development in legumes. Part of the activity of Nod factors may be directed towards alteration of endogenous plant growth regulator balance. The same bacterial Nod factors promoted the formation of globular embryos in the carrot cell line ts11. Whether there exist plant analogues of the Nod factors and whether these molecules are active as a more universal control system perhaps designed to initiate and or mediate gradients in auxin and cytokinin remains to be determined.

Cell Communication↗

Recurrent and migratory reflex sympathetic dystrophy syndrome.

A case of recurrent reflex sympathetic dystrophy syndrome (RSDS), involving consecutively three extremities in an otherwise healthy adult is described. In a period of four years follow-up she presented three RSDS episodes occurring without precipitating events and involving consecutively both lower legs and the left hand. The RSDS resolved without sequelae after treatment with physiotherapy and diclofenac in an early phase. RSDS is an often unrecognized entity which appears mostly confined to a single limb. Recurrent forms have also been described, sometimes with a migratory pattern. Involvement of upper and lower limbs in the same patient is thought to be infrequent.

Combined Modality Therapy↗

Effect of the cholecystokinin-receptor antagonist lorglumide on pancreatic enzyme secretion stimulated by bombesin, food, and caerulein, giving similar plasma cholecystokinin concentrations in the dog.

This study was undertaken to determine the role of cholecystokinin in pancreatic enzyme secretion stimulated by bombesin and a meal by (a) comparing the pancreatic enzyme output during bombesin infusion and after a meal to output during caerulein infusion and (b) comparing the inhibitory effect of the cholecystokinin-receptor antagonist lorglumide (CR-1409) on enzyme output in response to bombesin and food with the response to caerulein. Bombesin (90 pmol/kg per h) and caerulein (30 pmol/kg per h) were infused into seven dogs in doses giving similar plasma cholecystokinin peak increments as a meal (mean (SEM) 6.8 (0.8), 6.3 (1.2), and 5.7 (0.8) pM, respectively), together with either saline or 2 mg/kg per h of lorglumide. A background infusion of synthetic secretin 20.5 pmol/kg per h was given in each experiment. In addition, gastric acid secretion was determined in the experiments with bombesin and caerulein infusion. Pancreatic protein responses to bombesin (1231 (247) mg/h) and food (1430 (220) mg/h) were similar to the responses to caerulein (1249 (201) mg/h). Lorglumide inhibited pancreatic protein output during stimulation with bombesin by 60%, after the meal by 45%, and during caerulein infusion by 68%. Pancreatic bicarbonate output by bombesin, caerulein, and food was inhibited by lorglumide by 28%, 40%, and 38%, respectively. In contrast, lorglumide significantly increased gastric acid secretion from 1.12 to 7.98 mmol/h during bombesin infusion and from 0.52 to 7.62 mmol/h during caerulein infusion. In conclusion, cholecystokinin plays an important part in the stimulation of pancreatic enzyme secretion by bombesin and a meal in conscious dogs and it is involved in the regulation of gastric acid during stimulation by infusions of caerulein and bombesin.

Animals↗