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PubMed1990

Randomized controlled trial of late in-hospital angiography and angioplasty versus conservative management after treatment with recombinant tissue-type plasminogen activator in acute myocardial infarction.

Although both the European Cooperative Study Group and the Thrombolysis in Myocardial Infarction IIB trial indicated that angiography and angioplasty as routine measures after thrombolytic treatment do not improve clinical outcome in patients with acute myocardial infarction, the potential benefit of angioplasty may have been negated by the fact that the procedure was performed too soon (less than 32 hours) after admission. A similar study was designed in which delayed invasive treatment was compared with conservative treatment in 201 patients with acute myocardial infarction given recombinant tissue-type plasminogen activator. The 97 patients randomized to the invasive group underwent routine coronary angiography and angioplasty 5 +/- 2 days after thrombolytic therapy, whereas the 104 patients randomized to the conservative group underwent angiography only for recurrent postinfarction angina or exercise-induced ischemia. Baseline characteristics of both groups were similar. In the invasive group, 92 patients underwent angiography, 49 angioplasty and 11 coronary artery bypass surgery. In the conservative group, 40 patients experienced early ischemia, 39 underwent angiography, 20 angioplasty and 4 coronary artery bypass surgery. Reinfarction rate and preservation of left ventricular function at discharge or 8 weeks after discharge did not differ in the 2 groups. Total mortality after a mean follow-up of 10 months was 8 of 97 in the invasive and 4 of 104 in the conservative groups (p = 0.15). However, if only patients who died after the timing of the scheduled protocol catheterization in the invasive arm were included, mortality was 5 of 94 and 0 of 100 in the invasive and conservative treatment groups, respectively (p = 0.02). (ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1991

Highly conserved sequences in the 3'-untranslated region of the COL1A1 gene bind cell-specific nuclear proteins.

Sequencing of the 3' untranslated region (3'-UTR) of the human COL1A1 gene revealed numerous putative regulatory motifs and two highly conserved regions flanking the two polyadenylation sites. The conserved regions were separated by about 700 bp of less conserved sequences. The first region consists of almost all the 3'-UTR of the shorter (4.8 kbp) COL1A1 transcript. The second conserved domain includes a motif shared with several collagen genes. Both conserved domains bind cell-specific nuclear proteins suggesting that the 3'-UTR is important for cell specific expression of the COL1A1 gene.

Amino Acid Sequence↗

PubMed1993

Management of severe, early pre-eclampsia: is conservative management justified?

A retrospective analysis was performed to assess the fetal and maternal benefits of allowing women presenting with severe pre-eclampsia between 24 and 32 weeks to continue their pregnancy following treatment of their hypertension. Cases presenting in Oxford (conservative management) and in Birmingham (stabilisation and early intervention) were compared. Patients were considered to require treatment when their systolic blood pressure was > or = 170 mmHg systolic or > or = 110 mmHg diastolic, associated with at least 1+ proteinuria and hyperuricaemia. We compared gestation at delivery, birth weight and neonatal complications for each group, and any maternal morbidity. There were 28 patients in each group. Gestational age at delivery was significantly less in the group managed by early intervention. Those women managed conservatively gained a mean of 9.5 days (range 2-26 days; P < 0.05), and their birthweight was significantly greater (P < 0.05). There was a significant difference between the length of stay in the neonatal intensive care unit between the 2 groups (P < 0.05), the babies of those women managed conservatively staying a mean of 7.4 days less. There were fewer neonatal complications in those cases managed conservatively, the number of newborns with 1 or more complications in the early intervention group being 18 (64.3%), compared with 8 (28.6%) in the expectant management group (P = 0.0001). All of the women in the group managed by early intervention recovered with no severe complications. However, those women managed conservatively had a higher incidence of HELLP (2 cases) and ELLP syndrome (2 cases), 1 case requiring temporary renal dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗

PubMed1989

Alveolar phospholipids, hyperventilation and temperature of conservation of rat lungs.

Hyperventilation has been found to increase the phospholipid content of broncho-alveolar lavage fluids. Had the temperature of conservation of the lungs an influence? Two groups of rats were allowed to ventilate normally (NV), and two groups (HV) were induced to hyperventilate for 1 h by addition of a dead space. After sacrifice, the isolated lungs were kept for 25 min at 37 degrees C (NV37 and HV37), or 10 degrees C (NV10 and HV10), and then washed at the same temperatures. The phospholipid content of lavage fluid was only found to be increased in the HV37 group (P less than 0.05). Neither hyperventilation followed by conservation of lungs at 10 degrees C nor normal ventilation followed by conservation of lungs at 37 degrees C led to an increase in phospholipid content. It was the association of hyperventilation and conservation of lungs at 37 degrees C that led to the increase. In vivo hyperventilation is thought to lead to an equal increase in secretion and reabsorption of alveolar phospholipids, and conservation of the lungs at 37 degrees C was thought to lead to an imbalance between these two processes.

Animals↗

PubMed1986

The 3'-nucleotides of flavivirus genomic RNA form a conserved secondary structure.

The terminal noncoding regions of viral RNA genomes are presumed to contain signal sequences and sometimes also secondary structures involved in regulating viral RNA synthesis. Such signals would be expected to be highly conserved among related viruses. In order to identify replication signal features for flaviviruses we have compared the 3'-terminal nucleotide sequences of West Nile virus (WNV), Saint Louis encephalitis (SLE) virus, and yellow fever virus (YFV) genome RNAs. The existence of a stable 3'-terminal secondary structure was previously predicted by a cDNA sequence obtained from YFV genome RNA. We have confirmed the existence of this structure by direct RNA sequencing methods. Even though the size and shape of the 3'-terminal secondary structure is highly conserved, sequence conservation is restricted to the loop regions of the secondary structure and to 27 nucleotides immediately adjacent to the 5' side of the structure. The regions of conserved sequence represent likely signals for viral polymerase recognition and binding. However, the preservation of the configuration of the secondary structure by a means other than sequence conservation indicate that this structure is important for the survival of the virus. A WNV mutant, which replicates progeny genome RNA more efficiently than parental WNV, was found to have a 3'-genomic sequence identical to that of its parent virus. The sequence change conferring the phenotype of this mutant is therefore located in another region of the genome.

Base Sequence↗

PubMed1992

Variable and conserved structural elements of trypanosome variant surface glycoproteins.

The characterization of B cell epitopes on the trypanosome variant surface glycoprotein (VSG) rests on elucidation of variant specific amino acid sequences that may be exposed or buried as a result of the natural conformation of these molecules in the surface coat. Despite the fact that different VSGs have heterogeneous primary sequences and unique antigenic characteristics, recent high resolution X-ray crystallographic analyses of VSGs have revealed a conserved 3-dimensional structure common to these surface proteins [19]. We took advantage of this conserved structural conformation to help predict which variant subregions of VSG molecules may contain exposed or buried variant specific B cell epitopes. Using Staden data tables, we aligned the deduced amino acid sequence of Trypanosoma brucei rhodesiense LouTat 1 VSG, a molecule that has been characterized immunologically in this laboratory, with 12 other complete VSG sequences including the T. b. brucei MiTat 1.2 VSG that has been characterized in crystallographic studies. Results of this analysis predict that there are eight defined clusters of variant amino acids which may contribute to exposed B cell epitopes, and ten defined clusters of variant amino acids which may contribute to buried B cell epitopes, on all VSG molecules. Interestingly, this analysis also revealed a VSG consensus sequence in which certain conserved motifs are present in all VSGs. The shared elements of VSG sequences corresponded to known secondary structures present in MiTat 1.2, and included groups of conserved amino acids responsible for turns in subregions of the protein, for structural positioning of the variable residues on the exposed surface, and for the dimerization of VSG monomers. Overall, these observations may aid in the targeting and mapping of exposed and buried VSG specific B cell epitopes, and also may offer clues as to elements of the primary sequence that are important for the conserved 3-dimensional structure of antigenically distinct VSG molecules.

Amino Acid Sequence↗

PubMed1983

Environmental adaptation of proteins: strategies for the conservation of critical functional and structural traits.

Comparative studies of lactate dehydrogenases (LDHs) and skeletal muscle actins from vertebrates adapted to widely different temperatures and hydrostatic pressures reveal major conservative trends in protein evolution and adaptation. For enzymes, ligand binding, as estimated by apparent Michaelis constant (Km) values, is strongly conserved at physiological temperatures, pressures, intracellular pH values and osmotic compositions of different organisms. The catalytic rate constants (kcat values) of enzyme homologues are highest for enzymes of low-body-temperature organisms, a trend that can be interpreted in terms of temperature compensation of metabolism. For skeletal muscle actins, the enthalpy and entropy changes accompanying the assembly of filamentous (F) actin from globular (G) actin are highest in high-body-temperature species and especially low in polar and deep-sea fishes. The thermal stability of G-actin is positively correlated with adaptation temperature, except in the case of actins of deep-sea fishes, which are also highly heat stable. Hydrophobic interactions between actin subunits may be of reduced importance in low-body-temperature animals and, especially, in deep-sea fishes. The differences in enthalpy and entropy changes during the G-to-F transformation favor a close conservation of the equilibrium constant for actin assembly under physiological conditions of temperature and pressure for different species. These adaptive patterns in enzymes and actin are likely to reflect changes in protein primary structure. The appropriate values for protein traits such as ligand binding abilities and catalytic rates are also shown to be established by the composition of the low molecular weight constituents of the cytosol. For example, the use of a combination of urea and methylamine solutes for osmoregulation by marine elasmobranchs is shown to be a mechanism which permits the conservation of key protein traits at high osmolarities. The methylamine solutes such as trimethylamine-N-oxide have effects on proteins opposite to those of urea, and at the approximately 2:1 concentration ratio of urea to methylamines, these counteracting effects are virtually complete. Regulation of hydrogen ion activity (pH) also is shown to play a major role in the conservation of critical protein traits. The importance of temperature-dependent pH in ectotherms is discussed in terms of stabilizing binding abilities and maintaining correct regulatory and structural sensitivities of proteins. The buffering capacity of tissues reflects the potential of the tissue for generating acidic end-products during anaerobic metabolism. Skeletal muscle, especially white locomotory muscle of fishes, is highly buffered relative to red locomotory muscle and heart muscle.(ABSTRACT TRUNCATED AT 400 WORDS)

Actins↗

PubMed1996

Conservation of merozoite membrane and apical complex B cell epitopes among Babesia bigemina and Babesia bovis strains isolated in Brazil.

Babesia merozoite polypeptides bear surface exposed and neutralization-sensitive B cell epitopes and have been shown to induce partial protection against experimental challenge. Variation in these epitopes has been examined in a limited number of strains. In this study, utilizing strains of Babesia bovis and Babesia begemina from Matto Grosso do Sul in Brazil, we examined the conservation of epitopes bound by monoclonal antibodies developed against Mexico strains of B. bovis and B. bigemina. Apical complex B-cell epitopes, previously shown to be species-specific but common among otherwise antigenically distinct strains, were also conserved between clones of the Mexico strains and the Matto Grosso do Sul strains of each Babesia species. Mexico strain polypeptides bearing these epitopes were recognized by sera from cattle infected with the Matto Grosso do Sul strains. Two distinct epitopes on the B. bovis neutralization-sensitive merozoite surface antigen-1 (MSA-1) were also conserved between the Mexico Mo7 clone and the Matto Grosso do Sul strain, in contrast to previous studies which demonstrated variability among strains. Sera from cattle with B. bovis infections naturally acquired in Matto Grosso do Sul bound Mexico Mo7 MSA-1, demonstrating that conserved MSA-1 epitopes were recognized by the bovine immune system. Similarly, merozoite surface epitopes on the B. bigemina 45 kDa and 55 kDa glycoproteins were conserved on the Matto Grosso do Sul strain of B. bigemina.

Animals↗

PubMed1995

Conservative therapy of breast cancer in Queensland.

PURPOSE: Primary radiation therapy following breast-conserving surgery has been an accepted alternative to mastectomy in Europe and North America for many years. In Australia, however, the history of breast conservation for early invasive breast cancer is much shorter. The purpose of this study was to evaluate the results of breast conservation in a state-wide Australian radiotherapy service. METHODS AND MATERIALS: Between January 1982 and December 1989, 512 patients were treated with primary radiation therapy after breast conserving surgery. This analysis is based on a review of these patients, all of whom had Stage I or II breast cancer. RESULTS: With a median follow-up of 50 months, the 5-year actuarial rate of overall survival was 84% and disease-free survival was 80%. There have been 22 isolated local recurrences in the breast. The time to an isolated breast recurrence ranged from 12 to 83 months (median, 26 months). The 5-year actuarial rate of an isolated breast recurrence was 4%. The recurrence rate was higher for patients with involved margins (15% vs. 2%, p < 0.01). Local recurrence was also more likely in the presence of extensive ductal carcinoma in situ (DCIS), as opposed to no extensive DCIS (10% vs. 2%, p < 0.01). CONCLUSION: These results affirm that primary radiation therapy after breast conserving surgery in Queensland, has been given with a low rate of local recurrence, comparable to that obtained in other centers.

Actuarial Analysis↗

PubMed1995

Subareolar breast cancer: long-term results with conservative surgery and radiation therapy.

PURPOSE: It has been suggested that patients presenting with breast cancers within 2 cm of the nipple areolar complex represent a relative contraindication to conservative management due to either a compromised cosmetic result associated with sacrifice of the nipple areolar complex, reluctance to include the entire nipple areolar complex in the conedown field, or increased risk of multicentricity. We have reviewed our experience of conservatively treated patients with specific reference to the subset of patients presenting with tumors within 2 cm of the nipple areolar complex. METHODS AND MATERIALS: Between January 1970 and December 1989, 1014 patients with early stage breast cancer were treated at Yale-New Haven Hospital by excisional biopsy with or without axillary lymph node dissection. Of the 1014 charts reviewed, a total of 98 patients fulfilled the criteria of having a central/ subareolar breast cancer. Reexcision was performed on only 16 patients. Following conservative surgery, patients were treated with radiation therapy to the intact breast to a total median dose of 48 Gy with conedown to a total of 64 Gy. adjuvant systemic therapy and regional nodal irradiation were administered as clinically indicated. RESULTS: As of December 1993, the median follow-up for the 98 patients in this study was 9.03 years. The majority of patients had presented with either a palpable mass or a mammographically detected lesion. Three patients presented with Paget's disease, five with nipple discharge, and seven with nipple inversion. Ten of the 98 patients had the nipple areolar complex sacrificed at the time of surgery, while the remaining 88 patients had the entire nipple areolar complex included in the conedown field. Four of these 88 patients had the nipple partially blocked during the electron conedown. There were no significant complications associated with including the entire nipple areolar complex within the conedown field to a median dose of 64 Gy. Six of the 98 patients experienced a local recurrence, three experienced a regional recurrence, and nine experienced distant metastasis. The actuarial 10-year survival (0.79 +/- 0.06), distant disease-free survival (0.88 +/- 0.04) and breast recurrence-free survival (0.84 +/- 0.07) were not significantly different from those patients who presented with cancers in other parts of the breast. CONCLUSIONS: Patients presenting with subareolar breast cancers within 2 cm of the nipple areolar complex are suitable candidates for conservative surgery and radiation therapy. In the majority of patients in this study, the nipple areolar complex did not need to be sacrificed and could be safely included in the electron conedown field with acceptable complications and cosmesis. A subareolar breast cancer does not represent a relative contraindication to conservative management in patients with early stage breast cancer.

Breast Neoplasms↗

PubMed1996

Timing of radiotherapy and chemotherapy following breast-conserving surgery for patients with node-positive breast cancer. International Breast Cancer Study Group.

PURPOSE: A controversy exists regarding whether it is safe to delay radiation therapy until the completion of chemotherapy following breast-conserving surgery for patients with node-positive breast cancer. Within the context of two concurrent randomized clinical trials we had the opportunity to evaluate outcomes for patients who received breast irradiation after completing different durations of chemotherapy. METHODS AND MATERIALS: From July 1986 to April 1993 the International Breast Cancer Study Group (IBCSG) Trial VI randomly assigned 1554 pre/perimenopausal node-positive breast cancer patients to receive cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) for either three consecutive courses on months 1-3, or six consecutive courses on months 1-6, both with or without reintroduction CMF. IBCSG Trial VII randomly assigned 1266 postmenopausal node-positive breast cancer patients to receive tamoxifen for 5 years, or tamoxifen for 5 years with three early cycles of CMF, both with or without three courses of delayed CMF. Both trials allowed a choice of mastectomy, or breast-conserving surgery plus radiation therapy, and both were stratified by type of surgery. Radiotherapy was delayed until the initial block of CMF was completed; 4 or 7 months after surgery for pre/perimenopausal patients, and 2 or 4 months after surgery for postmenopausal patients. Over both trials, 718 eligible patients elected to receive breast-conserving surgery plus radiation therapy: 433 on Trial VI, and 285 on Trial VII. Four-year actuarial total failure rates (failure at any site), risks of developing distant metastases (DM at any time during observation), and overall survival (OS) were estimated using the Kaplan-Meier method. To avoid potential bias due to competing causes of failure, only patients who could be followed for at least 4 years (enrolled prior to July 1, 1990) were used to evaluate the patterns of first relapse site. Crude percents of local failure with or without other sites (LF), distant metastases including regional nodal failure (DM/RNF), or other first events (second primaries/death without recurrence) were estimated for each treatment group. For this report, an intent to treat analysis was performed at a median follow-up of 48 months. RESULTS: No differences were found in the 4-year actuarial total failure rates, risk of developing distant metastases, and overall survival among the two radiotherapy groups of each study. The cumulative incidence of types of first failure and the 4-year crude rates showed no treatment differences in the patterns of site of first event. Estimates for the 4-year crude percent of local failures were 8 and 9% for pre/perimenopausal patients who had radiation therapy at 4 or 7 months after surgery, and 3 and 6% for postmenopausal patients who had radiation therapy at 2 months or 4 months after surgery. CONCLUSIONS: For node positive patients receiving breast-conserving surgery followed by radiation therapy, the incidence of breast recurrence in the conserved ipsilateral breast within 4 years was between 8 and 9% for pre/perimenopausal patients and between 3 and 6% for postmenopausal patients. After 48 months of median follow-up, administering radiation therapy after three or six cycles of CMF for pre/perimenopausal women, or after no cycles or three cycles of CMF for postmenopausal women does not influence overall efficacy or local control in this series.

Adult↗

PubMed1992

Evidence favouring the hypothesis of a conserved 3'-5' exonuclease active site in DNA-dependent DNA polymerases.

The complete amino acid (aa) alignment of the N-terminal domain of 33 DNA-dependent DNA polymerases encompassing the putative segments Exo I, Exo II and Exo III, proposed by Bernad et al. [Cell 59 (1989) 219-228] to form a conserved 3'-5' exonuclease active site in prokaryotic and eukaryotic DNA polymerases, allowed us to identify and/or correct some of the most conserved segments (Exo I, II and III) in certain DNA polymerases. In particular, the aa region of T4 DNA polymerase and other eukaryotic (viral and cellular) DNA polymerases previously proposed as Exo I segment 1, did not align with the Exo I segment of Escherichia coli DNA polymerase I (PolI)-like and protein-primed DNA polymerases; instead, a new conserved region of aa similarity was identified in T4 DNA polymerase and eukaryotic (viral and cellular) DNA polymerases as their corresponding Exo I segment. Therefore, according to our alignment, the recently reported T4 DNA polymerase site-directed mutants, D189A and E191A [Reha-Krantz et al., Proc. Natl. Acad. Sci. USA 88 (1991) 2417-2421], do not correspond to what we now consider the critical Exo I motif of PolI. As discussed in this communication, the functional importance of conserved segments Exo I, Exo II and Exo III is supported by site-directed mutagenesis in PolI, and in phi 29, T7 and delta(Sc) DNA polymerases. Furthermore, genetically selected T4 DNA polymerase mutator mutants form two main clusters, centered in the conserved segment Exo III and in the newly identified Exo I segment.

Amino Acid Sequence↗

PubMed1995

One-year results of the Thrombolysis in Myocardial Infarction (TIMI) IIIB clinical trial. A randomized comparison of tissue-type plasminogen activator versus placebo and early invasive versus early conservative strategies in unstable angina and non-Q wave myocardial infarction.

OBJECTIVES: We report mortality, infarction, revascularization and repeat hospital admission events for 1 year after enrollment and randomization in the Thrombolysis in Myocardial Ischemia (TIMI) IIIB clinical trial. BACKGROUND: The purpose of this trial was to investigate the role of a thrombolytic agent added to conventional medical therapies and to compare an early invasive management strategy to a more conservative early strategy in patients with unstable angina and non-Q wave myocardial infarction. METHODS: There were 1,473 patients enrolled, and they received conventional anti-ischemic medical therapies. They were randomized to therapy with either tissue-type plasminogen activator (t-PA) or placebo and also to an early invasive management strategy with coronary arteriography at 18 to 48 h, followed by revascularization as soon as possible if appropriate, or, alternatively, to an early conservative strategy with arteriography and revascularization reserved for failure of initial therapy to prevent recurrent ischemia. The primary end point was a composite outcome variable and was assessed at 42 days. Patients were then managed entirely at the discretion of their treating physician. Follow-up contacts were made at 1 year. RESULTS: The incidence of death or nonfatal infarction for the t-PA- and placebo-treated groups was similar after 1 year (12.4% vs. 10.6%, p = 0.24). The incidence of death or nonfatal infarction was also similar after 1 year for the early invasive and early conservative strategies (10.8% vs. 12.2%, p = 0.42). A trial of this size should be able to detect differences in relative risk for death or infarction > or = 1.81 with a power of 80% at a significance level (alpha) of 0.01. Revascularization by 1 year was common, but was slightly more common with the early invasive than the early conservative strategy (64% vs. 58%, p < 0.001). This result was related entirely to a small difference in angioplasty rates (39% vs. 32%, p < 0.001) inasmuch as rates of bypass grafting by 1 year were equivalent (30% in each group, p = 0.50). The high rate of revascularization in both strategies was accompanied by comparable clinical status at the 1-year follow-up contact. CONCLUSIONS: In this large study of unstable angina and non-Q wave myocardial infarction, the incidence of death and nonfatal infarction or reinfarction was low but not trivial after 1 year (4.3% mortality, 8.8% nonfatal infarction). An early invasive management strategy was associated with slightly more coronary angioplasty procedures but equivalent numbers of bypass surgery procedures than a more conservative early strategy of catheterization and revascularization only for signs of recurrent ischemia. The incidence of death or nonfatal infarction, or both, did not differ after 1 year by strategy assignment, but fewer patients in the early invasive strategy group underwent later repeat hospital admission (26% vs. 33%, p < 0.001). Either strategy is appropriate for patient management; differences in hospital admissions and revascularization procedures, with their attendant costs, are likely to be minimal.

Adult↗

PubMed1994

Regulatory and coding regions of the segmentation gene hunchback are functionally conserved between Drosophila virilis and Drosophila melanogaster.

The segmentation gene hunchback (hb) is involved in setting up the anterior-posterior axis of the Drosophila embryo. It is expressed maternally and zygotically and it plays a key role in integrating the effects of the anterior and posterior maternal systems. The hb gene from D. virilis has previously been cloned and was shown to be well conserved in its coding region, but less so in its upstream region which shows a more patchy pattern of conserved and diverged sequences. This work deals with the functional conservation of hb between the two species. We have mapped two additional regulatory elements for the expression of hb in the early embryo, namely the enhancer for the maternal expression and the enhancer region for the late blastoderm expression. Fragments containing these two elements, the previously identified bicoid dependent element for the early blastoderm expression of hb and the coding region were taken from D. virilis and tested in the D. melanogaster background. We find that all enhancer elements as well as the coding region are functionally conserved between the two species. Comparison of the upstream sequences that include the enhancer region for the late blastoderm expression reveal seven highly conserved blocks. Some of these contain consensus binding sites for transregulatory factors that are likely to control the respective expression domains.

Amino Acid Sequence↗

PubMed2006

Identifying patients at risk of compromised margins following breast conservation for lobular carcinoma.

BACKGROUND: The association of invasive lobular carcinoma with high rates of compromised margins in breast conservation makes choice of operation for these patients difficult. We sought to identify patients at risk of compromised margins following breast conservation surgery. METHODS: We reviewed all patients with invasive lobular and invasive ductal carcinoma over a 5-year period (1999-2004). The imaging, pathology and surgical details of patients with invasive lobular carcinoma undergoing breast conservation were analyzed. RESULTS: A total of 991 patients with invasive ductal carcinoma and 150 patients with invasive lobular carcinoma were identified. Lobular carcinomas had a compromised margin rate of 49% (n = 38/77) in breast conservation compared to 24% (n = 143/588) of ductal carcinomas (P < .0001). Mammographic size (P = .017), pathological size (P = .01), age (P = .03), multifocality (P < .0001), and lymphovascular invasion (P = .015) were significantly associated with compromised margins. CONCLUSION: Invasive lobular carcinoma has a 49% rate of compromised margins following breast conservation. Mammographic size greater than 1.5 cm and young age were preoperative factors predictive of compromised margins.

Breast Neoplasms↗

PubMed2005

Fibril modelling by sequence and structure conservation analysis combined with protein docking techniques: beta(2)-microglobulin amyloidosis.

Obtaining atomic resolution structural models of amyloid fibrils is currently impossible, yet crucial for our understanding of the amyloid mechanism. Different pathways in the transformation of a native globular domain to an amyloid fibril invariably involve domain destabilization. Hence, locating the unstable segments of a domain is important for understanding its amyloidogenic transformation and possibly control it. Since relative conservation is suggested to relate to local stability, we performed an extensive, sequence and structure conservation analysis of the beta(2)-microglobulin (beta(2)-m) domain. Our dataset include 51 high resolution structures belonging to the "C1 set domain" family and 132 clustered PSI-BLAST search results. Segments of the beta(2)-m domain corresponding to strands A (residues 12-18), D (45-55) and G (91-95) were found to be less conserved and stable, while the central strands B (residues 22-28), C (36-41), E (62-70) and F (78-83) were found conserved and stable. Our findings are supported by accumulating observations from various experimental methods, including urea denaturation, limited proteolysis, H/D exchange and structure determination by both NMR and X-ray crystallography. We used our conservation findings together with experimental literature information to suggest a structural model for the polymerized unit of beta(2)-m. Pairwise protein docking and subsequent monomer stacking in the same manner suggest a fibril model consistent with the cross-beta structure.

Amyloid↗

PubMed2006

The conservative management of facial fractures: indications and outcomes.

BACKGROUND: With little in the published literature on the conservative management of facial fractures we set out to determine whether our current criteria for treatment are valid. METHOD: Two hundred and thirty adult patients with fractures of the facial skeleton were treated conservatively by our unit between February 1997 and January 2003. Their notes were reviewed retrospectively. RESULTS: Most patients were males (76%), the average age was 38 years, and drugs or alcohol were a significant aspect of the history in 30% of the cases. The most common mechanism of injury was assault (47%), followed by falls and sporting injuries. Fifty percent of the fractures involved the orbital or orbito-zygomatic complex, and 55% had associated injuries. Average follow-up was for six weeks (range 0-44 weeks). Most patients were managed conservatively based on our current criteria of un-displaced/minimally displaced fracture (57%); or minimal/no symptoms (24%). At final review, a number had residual symptoms, but only three required corrective surgery. The other reasons for conservative management included patient non-compliance (11%), and medical contraindications (8%). CONCLUSION: Our results support current indications for the conservative management of facial fractures, but emphasise the need for ongoing follow-up of these patients.

Adolescent↗

PubMed2005

Audit of local recurrence rates following 'ultra'-conservative surgery for invasive breast cancer--a boost to the breast?

BACKGROUND: Conservative breast surgery with postoperative radiotherapy and appropriate systemic therapy is associated with similar outcomes when compared with mastectomy. The reported 5 year local recurrence rate varies between 3% and 15%. We prefer a more conservative 'complete' local excision rather than 'wide' local excision combined with post-operative radical radiotherapy and tumour bed boost with the aim of achieving optimal cosmesis. AIMS: Our review was undertaken to assess whether or not this 'ultra' conservative approach was compromising long-term local control. METHODS: Case notes and pathology reports of patients who underwent conservative surgery for breast cancer from January 1983 to February 2001 were accessed for this audit. Patient demographic data and tumour characteristics were noted. The primary outcome data were the number of local recurrences following invasive breast cancer at 5 and 10 years and the distance from the tumour to the closest margin of excision. RESULTS: At 5 and 10 years there were 16/451 and 5/124 local recurrences, with a local recurrence rate of 3.5% (95% CI, 1.7-4.7%) and 4.1% (95% CI, 0.47-6.5%), respectively. Complete data with regards to the closest histological margin of excision were available in 423 patients. One hundred and sixty-five patients (39%) had their tumours excised with a distance of less than 1 mm to the closest margin. Nearly, all tumours (97.8%) were excised with the distance to the closest margin less than 1 cm and 81% with 5 mm or less. CONCLUSION: It is possible to achieve low local recurrence rates after very conservative surgery for breast cancer when this is combined with radical radiotherapy and an additional tumour bed boost.

Adult↗