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B Hamberger

Publications and source records attributed to B Hamberger.

At least 19 recordsLinked to original sources
PubMed2006

The genome of black cottonwood, Populus trichocarpa (Torr. & Gray).

We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

Arabidopsis↗
PubMed2006

Predictors of outcome in patients with papillary thyroid carcinoma.

AIM OF THE STUDY: To evaluate prognostic factors with respect to the outcome in a consecutive series of patients with papillary thyroid carcinoma (PTC) treated at the same institution during a 20-year-period, and to evaluate further the predictive ability of outcome of the pTNM, AMES and MACIS prognostic systems in these patients. MATERIALS AND METHODS: Two hundred and twenty consecutive patients operated on for primary PTC at the Karolinska Hospital between 1980 and 1999 were examined retrospectively. Patient and tumour characteristics at the time of surgery were compared to the patients' outcomes. Univariate and multiple logistic regression analyses were used to identify independently significant prognostic factors with respect to the outcome. In addition, the classification of the patients according to the pTNM, AMES and MACIS prognostic systems were compared to the outcomes. RESULTS: At the end of the follow-up period 201 patients were still alive without disease, 6.5% had died from PTC and 2.5% were alive with persisting disease. In 16 patients, radical surgery could not be performed due to extensive tumour growth and/or distant metastases. Recurrences were detected in 14% of the patients considered as radically operated. The strongest independent predictors for local or distant recurrences and poor clinical outcome were the lack of radical surgery and increasing tumour size. In this investigation MACIS appeared to be the better system, regarding efficacy in predicting the outcome of PTC. CONCLUSION: Removal of all tumour tissue appears most important to a favorable outcome and in our patients MACIS appears the most useful prognostic system taking completeness of resection into account.

Adolescent↗
PubMed2006

Cytochrome P450 mono-oxygenases in conifer genomes: discovery of members of the terpenoid oxygenase superfamily in spruce and pine.

Diterpene resin acids, together with monoterpenes and sesquiterpenes, are the most prominent defence chemicals in conifers. These compounds belong to the large group of structurally diverse terpenoids formed by enzymes known as terpenoid synthases. CYPs (cytochrome P450-dependent mono-oxygenases) can further increase the structural diversity of these terpenoids. While most terpenoids are characterized as specialized or secondary metabolites, some terpenoids, such as the phytohormones GA (gibberellic acid), BRs (brassinosteroids) and ABA (abscisic acid), have essential functions in plant growth and development. To date, very few CYP genes involved in conifer terpenoid metabolism have been functionally characterized and were limited to two systems, yew (Taxus) and loblolly pine (Pinus taeda). The characterized yew CYP genes are involved in taxol diterpene biosynthesis, while the only characterized pine terpenoid CYP gene is part of DRA (diterpene resin acid) biosynthesis. These CYPs from yew and pine are members of two apparently conifer-specific CYP families within the larger CYP85 clan, one of four plant CYP multifamily clans. Other CYP families within the CYP85 clan were characterized from a variety of angiosperms with functions in terpenoid phytohormone metabolism of GA, BR, and ABA. The recent development of EST (expressed sequence tag) and FLcDNA (where FL is full-length) sequence databases and cDNA collections for species of two conifers, spruce (Picea) and pine, allows for the discovery of new terpenoid CYPs in gymnosperms by means of large-scale sequence mining, phylogenetic analysis and functional characterization. Here, we present a snapshot of conifer CYP data mining, discovery of new conifer CYPs in all but one family within the CYP85 clan, and suggestions for their functional characterization. This paper will focus on the discovery of conifer CYPs associated with diterpene metabolism and CYP with possible functions in the formation of GA, BR, and ABA in conifers.

Algorithms↗
PubMed2005

Nimodipine and microsurgery induced recovery of the vocal cord after recurrent laryngeal nerve resection.

Transection of the recurrent laryngeal nerve leads to permanent palsy of the vocal cord. Experimental studies have confirmed that nimodipine increases the pace of axonal regeneration. We present a case of a 19-year-old male, suffering a thyroid cancer disease, who was subjected to unilateral resection of the recurrent laryngeal nerve during surgery. The nerve was repaired with a nerve graft and the patient further treated with nimodipine for 3 months. Evaluation of the patient showed normalization of voice, movement of the vocal cord on the injured side, and electromyography evidence of reinnervation of the larynx muscles at 15 months after surgery.

Adenocarcinoma, Papillary↗
PubMed2003

The management of benign and malignant pheochromocytoma and abdominal paraganglioma.

AIMS: To report treatment and outcome in patients with malignant and benign pheochromocytoma and abdominal paraganglioma. METHODS: Review of clinical and therapeutic features in 85 patients with pheochromocytoma or abdominal paraganglioma between 1976 and 1999. RESULTS: Thirty-nine of 85 patients presented with symptoms other than classical paroxysmal attacks. Paragangliomas were more often malignant (7/15) than pheochromocytomas (7/70). No recurrences have occurred in 71 patients with tumours initially classified as benign after a median follow-up time of 144 months (range 7-287). Nine of 14 patients with tumours classified as malignant have developed metastasis and/or local recurrence. Treatment of malignant tumours with cyclophosphamide, vincristine and dacarbazine (CVD) improved or stabilised the disease in three of four patients. CONCLUSION: Life long follow-up of patients with benign pheochromocytoma is not necessary. Combination chemotherapy (CVD) is a valid option in the treatment of malignant pheochromocytomas and abdominal paragangliomas.

Abdominal Neoplasms↗
PubMed2001

[Hereditary thyroid cancer can be cured by prophylactic surgery].

Multiple endocrine neoplasia type 2 (MEN 2) is a rare syndrome in which the consequences for the patient and family members are considerable. Mutation analysis of the RET proto-oncogene is crucial for decision-making regarding each patient. Today, carriers of MEN 2 mutations should be offered prophylactic thyroidectomy with the potential to eliminate the risk for potentially lethal medullary thyroid carcinoma (MTC). Here, we present the first Swedish experience of such operations performed mainly on the basis of genetic analysis. Twenty patients underwent total thyroidectomy at a mean age of 13.5 (6-43) years. In all cases, either manifest MTC (n = 11) or C-cell hyperplasia was found. So far, no patient has any sign of recurrence or developmental insufficiency at 1-5 years follow-up. As the medical and ethical problems in this group of patients are substantial, and as the operations are performed in otherwise healthy children, they should be treated at centers with adequate multidisciplinary expertise and competence.

Adolescent↗
PubMed2001

In vitro release of aldosterone and cortisol in human adrenal adenomas correlates to mRNA expression of steroidogenic enzymes for genes CYP11B2 and CYP17.

Adenomas of the adrenal cortex cause different disorders depending on the main steroid synthesized and released. The aim of this research is to increase our understanding of the pathophysiology of steroidogenesis in adrenocortical disorders by comparing the release of steroids from adrenocortical adenomas in vitro with the messenger RNA (mRNA) expression of steroid synthesizing enzymes. Fourteen patients with adrenal tumors were included in the present study; nine were diagnosed with primary aldosteronism and three with Cushing's syndrome. Two patients had an adrenal tumor discovered on computed tomography (CT) during workup for an unrelated disease. Serum cortisol, plasma aldosterone, and urinary catecholamines were normal. Tissue was taken for in vitro steroid release, and aldosterone and cortisol in the medium after a 1-hour incubation were determined. Oligonucleotide probes with sequences complementary to mRNAs encoding for the steroid synthesizing enzymes 11 beta-hydroxylase (CYP11B1), 18-hydroxylase (CYP11B2), 17 alpha-hydroxylase (CYP17), and 21-hydroxylase (CYP21) were synthesized (Genset, Paris, France) and in situ hybridization was performed. Moderate expression of CYP11B2 and low expression of CYP11B1 were seen in the zona glomerulosa. The zona fasciculata of the control adrenals expressed a high signal of CYP11B1, whereas the expression of CYP11B2 was very low. There was considerable variation in aldosterone release from the aldosteronomas, whereas the tumors from the Cushing patients showed no detectable release of aldosterone. In contrast, tumors from patients with primary aldosteronism, Cushing's syndrome, and no hyperfunction all had the ability to synthesize and release cortisol in vitro. The highest cortisol release was found in tumors from patients with Cushing's syndrome, but also the nonhyperfunctioning tumors and some of the aldosteronomas released significant amounts of cortisol. The two patients with highest release of aldosterone in vitro showed the highest expression of CYP11B2 and the lowest expression of CYP11B1 and CYP17. The remaining aldosteronomas had low expression of CYP11B2, similar to the two other groups. Expression of CYP11B1 was high as expected in the Cushing adenomas, but also the two nonhyperfunctioning tumors and some of the aldosteronomas showed a moderate expression. Adenomas from Cushing's syndrome, nonhyperfunctioning adenomas, and some of the aldosterone-producing adenomas had moderate to high expression of CYP17. This paper presents new means for functional characterization of adrenocortical tumors. Diagnosis of an aldosteronoma is often difficult, and with the advent of these methods it is possible to determine the functional capacity of a tumor, once it is removed. This is of special interest if the patient remains hypertensive postoperatively, and it is not clear whether the patient indeed had a functioning tumor.

Adrenal Cortex Neoplasms↗
PubMed2000

Expanding role of fine-needle aspiration cytology in thyroid diagnosis and management.

In non-iodine-deficient areas, 4% to 7% of the population are reported to have thyroid abnormalities. Prophylactic operations of these nodules in the thyroid are not indicated and not cost-effective, as at least four of five nodules are colloid goiter and only a few are malignant. The need for a reliable preoperative diagnosis is great, and fine-needle aspiration (FNA) is now considered the first choice during workup for thyroid nodules. The steps in the FNA procedure are clinical examination and localization of the target lesion, aspiration, preparation of smears, and collecting material for ancillary microscopy techniques. All these steps must be exercised to allow optimal use of FNA. It can also be combined with various other methods, such as immunohistochemistry of thyroglobulin and calcitonin, analysis of nuclear DNA, DNA preparation for molecular biology analyses, and magnetic resonance spectra. The accuracy of the clinical routine in our unit was evaluated by studying the 5-year outcomes of almost 4000 FNAs of the thyroid. The results were good, with only a few false-negative and false-positive results; but the problem of differentiating follicular adenoma from follicular carcinoma remains a significant problem. It is now well established that FNA biopsy and cytology is the best modality available for the workup of thyroid nodules and is widely utilized in endocrine surgical centers worldwide.

Biopsy, Needle↗
PubMed1999

Malignant human renin producing paraganglionoma-localization with 123I-MIBG and treatment with 131I-MIBG.

A 22-year-old woman presenting severe hypertension and hypokalaemia is described. Initial evaluation showed a large tumour localized at the position of the left adrenal gland. Subsequent surgery temporarily relieved all signs and symptoms caused by the tumour. The symptoms relapsed after a 2-year disease-free interval. At re-evaluation, the tumour was shown to produce an uncontrolled secretion of renin, thus triggering aldosterone-dependent hypertension. This report describes the diagnosis, treatment and clinical course of this unique patient with a malignant paraganglionoma of adrenal origin.

3-Iodobenzylguanidine↗
PubMed1999

Long term experience after subtotal adrenalectomy for multiple endocrine neoplasia type IIa.

OBJECTIVE: To evaluate the long-term results after subtotal adrenalectomy in patients with multiple endocrine neoplasia type IIa (MEN IIa). DESIGN: Retrospective study. SETTING: University Hospital, Sweden. SUBJECTS: Five patients who underwent partial adrenalectomy between 1985 and 1989. INTERVENTIONS: Subtotal adrenalectomy with a rim of cortical tissue left in situ. MAIN OUTCOME MEASURES: Follow up by interview, measurement of cortisol and catecholamine excretion in urine, and cortisol concentration in serum in response to stimulation with ACTH. RESULTS: Three patients took no corticosteroids regularly, but during upper respiratory tract infections, or periods of severe stress they took 25 mg cortisone acetate daily. This is confirmed by their normal values of 24 hour urinary cortisol excretion and subnormal responses to an ACTH-stimulation test. The fourth and fifth patients had low concentrations of endogenous corticosteroids postoperatively, which is being replaced with 25 mg cortisone acetate daily. Postoperatively all five patients had low urinary adrenaline excretion. CONCLUSION: Subtotal adrenalectomy in patients with MEN IIa resulted in basal endogenous corticosteroids within the reference range in three of five patients. There was no evidence of reduced adrenocortical function with time, nor were there any signs of recurrence of the pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1998

Surgery in Sweden.

Sweden has 9 university and regional hospitals and about 75 county hospitals. These hospitals are funded by counties that directly tax their inhabitants. In addition, the university hospitals use state money for education and research. The private sector performing major surgical procedures is small but slowly increasing. Reorganizations and closings of smaller hospitals are continually occurring, and various organizational models are being tested. Surgical care for inpatients is free for Swedish citizens; however, there is a small fee for outpatient care (US $10-$20 per visit). Education in surgery is changing rapidly with the introduction of new methods. Clinical research closely connected to basic sciences will be of profound importance for future development. The present article is confined mainly to general surgery in Sweden, but it also covers some general aspects of medicine in Sweden.

General Surgery↗
PubMed1998

Quality of life aspects and costs in treatment of Graves' hyperthyroidism with antithyroid drugs, surgery, or radioiodine: results from a prospective, randomized study.

The patients' views and costs of three different forms of treatment for Graves' hyperthyroidism were investigated. The study comprises 174 patients with Graves' hyperthyroidism who were stratified into two age groups: 20 to 34 years and 35 to 55 years. The younger group was randomly assigned to treatment with antithyroid drug plus thyroxine for 18 months or subtotal thyroidectomy, and in the older group iodine-131 was added as a third alternative. The patients' views of their therapy were based on a questionnaire formulated to identify possible differences between the three treatment forms. The costs were assessed by analyzing the official hospital reimbursement system for both outpatient and inpatient costs for a period of 2 years from the day of randomization. The results show that no significant differences in opinion were found between the five treatment groups with regard to any of the questions. Furthermore, only 10% of the patients expressed slight and 3% major hesitation to recommend the treatment form received to a friend with similar disease. Twenty percent of the patients with endocrine ophthalmopathy reported the eye problems to be much more troublesome and 14% somewhat more troublesome than the thyroid problems. The cost proportion between the medical and surgical treatment in the young group was 1:2.5 (1 = 1126 United States dollars [USD]) before and 1:1.3 (1 = 2284 USD) after inclusion of the relapse costs. The proportion between the medical, surgical, and iodine-131 treatment in the older group was 1:2.5:1.6 (1 = 1164 USD) before and 1:1.6:1.4 (1 = 1972 USD) after inclusion of the relapse costs.

Adult↗
PubMed1996

[MIBI-scintigraphy. A simple and reliable method for localization of pathological parathyroid glands].

99Tcm-sestamibi scintigraphy was used to localise enlarged parathyroid glands in 25 patients with primary hyperparathyroidism previously operated in the neck, 20 of whom had recurrent disease and five had previously undergone surgery for thyroid disorders. Of the 18 patients for whom positive scans were obtained, nine were operated on the scan findings being confirmed. Crucial information was provided in two cases of intrathyroidal and one case of intramediastinal localisation of the pathological gland were not operated on as the hypercalcaemia was only marginal or the symptoms were vague. Though preoperative localisation of pathological parathyroid glands is a prerequisite for neck exploration in patients with persistent or recurrent hypercalcaemia due to primary (or secondary) hyperparathyroidism, the procedure is not cost-effective before the initial operation.

Adult↗
PubMed1996

Graves' hyperthyroidism: treatment with antithyroid drugs, surgery, or radioiodine--a prospective, randomized study. Thyroid Study Group.

To analyze the benefits and risks of three common treatments, we randomly assigned 179 patients with Graves' hyperthyroidism as follows: 60 patients, 20-34 yr of age (young adults), received antithyroid drugs for 18 months (medical) or subtotal thyroidectomy (surgical), and 119 patients, 35-55 yr of age (old adults), received medical, surgical, or radioiodine (iodine-131) treatment. The follow-up time was at least 48 months. Antithyroid drugs, surgery, or iodine-131 treatment normalized the mean serum hormone levels within 6 weeks. The risk of relapse was highest in the medically treated young and old adults (42% vs. 34%), followed by that in those treated with iodine-131 (21%) and that in the surgically treated young and old adults (3% vs 8%), respectively. Elevated TSH receptor antibodies at the end of medical therapy or increasing TSH receptor antibodies values after medical or surgical treatment increased the probability of relapse. Development or worsening of ophthalmopathy was not associated with relapse per se. Ninety percent of the subjects in all groups were satisfied with the treatment they received. No significant difference in sick-leave due to Graves' or other diseases was seen during the first 2 yr after initiation of therapy. The increased risk of ophthalmopathy in patients with high serum T3 levels, especially when treated with iodine-131, and the relatively high frequency of relapse after treatment with antithyroid drugs are important factors to consider when selecting therapy for Graves' disease.

Absenteeism↗