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Search for Drosophila genes encoding a conserved domain present in the achaete-scute complex and myc proteins.

Several genes of the achaete-scute complex (AS-C) of Drosophila melanogaster encode a 60 amino acids long conserved domain which shares a significant homology with a region of the vertebrate myc proteins. Based on these results, the existence of a family of Drosophila genes that would share both this conserved domain and the neurogenic function of the AS-C has been postulated. To test this proposal, we have searched a D. melanogaster genomic library with a probe that encodes the conserved domain. Only under very low stringency hybridization conditions, clones not belonging to the AS-C cross-hybridized with the probe. Those that gave the strongest signals were characterized. Sequencing of the cross-hybridizing regions showed that they had no significant homology with the conserved domain, the sequence similarity extending at the most for 37 nucleotides. Although our results do not conclusively disprove the existence of a family of AS-C-like genes, they indicate that the conservation of the domain would be lower than that found for shared motifs in other families of Drosophila developmental genes.

Amino Acid Sequence↗

Poly(ADP-ribose) polymerase: structural conservation among different classes of animals and its implications.

Poly(ADP-ribose) polymerase cDNAs have been isolated from different classes of animals. Cloning of genes from lower eukaryotes has allowed us to investigate directly the biological functions of poly(ADP-ribosyl)ation in vivo. The conservation of specific regions among mammals, chicken, Xenopus laevis, and Drosophila melanogaster reveals the essential structural elements required for recognition of breaks in DNA and for catalytic activity. Cys, His and basic residues in the zinc-finger consensus region are conserved. The carboxyl terminal region corresponding to an NAD-binding domain is strongly conserved. The dinucleotide-binding consensus sequence and beta 1-alpha A-beta 2, Rossmann fold structure, and beta-sheet structures are completely conserved from mammals to insect. In Drosophila, a putative leucine-zipper motif has been identified, and other poly(ADP-ribose) polymerases also contain an alpha-helical, amphipathic structure in the auto-modification domain. In this article, we review the recent structural analyses of the functional domains of poly(ADP-ribose) polymerase in phylogenetically divergent species, and discuss the implications of structural conservation for its biological functions.

Amino Acid Sequence↗

Conservation of Living Resources in a Changing World

/ Conservation of living resources is no longer parochial in scope; it is a global challenge. Ecological, social, political, and business interests operate in a network that reaches across seas, continents, and nations. Industries, including the electric utility industry, are diversifying in products and expanding into international markets. They soon discover that, while all nations have common goals for their peoples, conservation and environmental issues in less-developed nations have different dimensions and norms than are encountered in Western, affluent societies. In developing countries, survival is more of an issue than quality of life, and burgeoning human numbers have put tremendous pressures on resources including wildlife and its habitats. Human population, urbanization of society, changes in single-species to ecosystem and landscape levels of management, and protectionists and animal rights philosophies are influences with which conservation of resources and the environment must contend. The human condition and conservation efforts are inextricably linked. Examples to demonstrate this fact are given for Project Tiger in India, the jaguar in Latin America, and the Serengeti ecosystem in Kenya and Tanzania.KEY WORDS: Conservation; Global, Developed nations; Developing nations; Wildlife; Habitat

Journal Article↗

Disc degeneration in young patients with isthmic spondylolisthesis treated operatively or conservatively: a long-term follow-up.

The purpose of this long-term follow-up was (1) to investigate disc changes in the olisthetic segment in patients treated conservatively, (2) to compare disc changes above the slipped vertebra in conservatively treated patients with those in operatively treated patients, and (3) to establish possible relations of disc changes to the degree of the slip and to subjective back pain symptoms of the patients. The subjects were 227 patients with isthmic L5 olisthesis diagnosed under 20 years of age (mean 13.8 years) with a mean follow-up of 15.4 (range 5-30) years. Of these, 145 patients had been treated with segmental fusion and 82 had been treated conservatively. At follow-up, standing anteroposterior and lateral radiographs as well as flexion/extension views of the lumbar spine were taken. Disc degeneration was graded semiquantitatively: 0 = normal disc height, 1 = decrease of disc height < 50%, 2 = decrease > or = 50%, and 3 = obliteration of the disc. In the conservatively treated patients degeneration of the olisthetic disc was distributed by grade as follows: O: n = 38, 1: n = 24, 2: n = 14, 3: n = 6. No motion at all was observed in the olisthetic segment in 40 patients (48%) with a mean slip of 30%, segmental motion of 4 degrees-18 degrees was found in 42 patients with a mean slip of 14%. There was a statistically significant association of the degree of slip to the severity of disc degeneration and non-mobility of the segment. Grade 1 degeneration of the L4/5 disc occurred in 25.6% of the conservatively treated patients and in 32% of 48 patients treated with L5-S1 fusion. This correlated with the severity of the slip, but not with pain symptoms or pathologic segmental mobility at the time of follow-up. Out of 84 patients with L4-S1 fusion, in 17% grade 1 degeneration of the L3/4 disc was observed, and 3 out of 13 patients (23%) with L3-S1 fusion had grade 1 degeneration of the disc above the fusion. The disc changes had no correlation with subjective pain symptoms. It is concluded that the natural course of isthmic spondylolisthesis is associated with disc degeneration and spontaneous stabilization of the olisthetic segment. Fusion operations do not significantly increase the rate of disc degeneration in the adjacent disc above the fusion after a mean postoperative follow-up of 13.8 years. No correlation between the number of degenerated discs or the degree of degeneration and subjective low back pain symptoms was found.

Adolescent↗

Role of conservation therapy for invasive lobular carcinoma of the breast.

BACKGROUND: Invasive lobular carcinoma (ILC) accounts for 5% to 10% of all invasive breast cancers. Although breast conservation therapy using local excision and postoperative irradiation is a standard therapy for early invasive ductal breast cancer, the result of this strategy in ILC is not well documented. We sought to determine the rate of locoregional recurrence after breast conservation therapy in patients with ILC. METHODS: A retrospective review of 74 patients with ILC treated with breast conservation therapy at The University of Texas M. D. Anderson Cancer Center (n = 43) or The John Wayne Cancer Institute (n = 31) between 1977 and 1993 was performed. RESULTS: The median age of patients was 60 years, and median follow-up was 56 months (range 1 to 207 months). Thirty-nine patients had American Joint Committee on Cancer stage I disease, 30 had stage IIa disease, and five had stage IIb disease. All patients underwent surgical resection and postoperative radiation therapy. Twelve patients received postoperative adjuvant chemotherapy, and 27 patients were treated with adjuvant hormonal therapy. The 5-year actuarial locoregional recurrence rate was 9.8%, and the median time to recurrence was 77 months (range 41 to 113 months). Patients with positive or close (< or = 1 mm) surgical margins were at increased risk for local recurrence on univariate analysis (p = 0.034). Of the nine patients with breast recurrence, six underwent salvage therapy with total mastectomy and are disease free at the time of this writing, two patients died of distant disease, and one is alive with local disease at the time of this report. The 5-year disease-specific survival rate was 93.7%. CONCLUSIONS: Breast conservation therapy for ILC achieves locoregional control in the majority of patients. However, long-term follow-up of patients is important because many local recurrences following breast conservation therapy are late events.

Adult↗

An analysis of relapsed breast cancer in patients previously treated with breast conserving surgery.

BACKGROUND: Recent advances in breast surgery have focused on breast conserving surgery in combination with radiotherapy. In the present study, we examine by retrospective analysis 105 patients with breast cancer who received breast conserving surgery for factors influencing disease free survival. METHODS: The analysis was performed on 105 patients with breast cancer who received breast conserving surgery in our department, including 38 patients without radiotherapy and 67 patients treated with radiotherapy. The disease-free survival of the patients was analyzed using the Kaplan-Meier method. The relapsed patients were assessed by examining pathological features and gene expression by immunohistochemical staining. RESULTS: There was no significant difference in the disease free survival at 5 years between patients without radiotherapy (89.6%) and with radiotherapy (94.5%). Relapse after breast conserving surgery was found in 6 patients including 4 patients without radiotherapy and 2 patients with radiotherapy. Local relapse and bone metastasis were found in 4 (3.8%) and 2 patients, respectively. Among the 4 local relapses, 1 patient had received radiotherapy and 3 patients had not. There was no significant difference between the type of relapse in terms of lymph node metastasis, hormone receptor, nuclear grade and intraductal component, but more vessel invasion was observed in the 2 cases with bone metastasis. The overexpression of apoptosis and angiogenesis genes such as p53, Bax, Bcl-XL, Bcl-2 and VEGF was not common in the relapsed patients, whereas the overexpression of drug resistance genes, either P-gp or MRP1, was found in the all patients. CONCLUSIONS: Although radiotherapy may reduce the incidence of local relapse and increase disease free survival after breast conserving surgery, the development of an effective adjuvant chemotherapy based on drug resistance markers, is also required.

Adult↗

3D-MR mammography-guided breast conserving surgery after neoadjuvant chemotherapy: clinical results and future perspectives with reference to FDG-PET.

BACKGROUND: Three dimensional MR Mammography (3D-MRM) can detect tumor extension more accurately than mammography or ultrasound. There are two shrinkage patterns observed by 3D-MRM after neoadjuvant chemotherapy. Concentric shrinkage is a good indication for breast conserving surgery. On the other hand, a dendritic pattern was represent ductal spread. Therefore, we developed MRM guided mapping to aid BCS for tumors showing a dendritic pattern. METHODS: Fifteen patients consisting of 8 stage II (T > 3.5 cm) cases and 7 stage IIIa cases aged 39 to 61 years (mean 47-8 years) were treated with AT neoadjuvant chemotherapy with the aim of performing breast conserving surgery. All patients were examined by 3D-MRM before and after neoadjuvant chemotherapy. Breast conserving surgery indications were determined by tumor volume reduction and shrinkage patterns on 3D-MRM. Supine position mapping using MRM was performed for dendritic type tumors. FDG-PET was simultaneously performed for one case with bilateral breast cancer. RESULTS: Breast conserving surgery was performed for 13 of the 15 cases. One case underwent re-operating and mastectomy because of a positive margin. One case had microscopically positive margin and received boost radiation. Therefore, 11 of 15 cases (73.3%) underwent BCS and achieved negative margins under MRM guidance. PET scanning can detect residual tumor and occult metastasis but it is not suitable for mapping because of its spatial resolution. CONCLUSIONS: 3D-MRM is a useful modality to select appropriate cases for breast conserving surgery after neoadjuvant chemotherapy. FDG-PET can also detect residual tumor or occult metastasis but it may not be suitable for mapping. Because both examinations have potential, further evaluation of their clinical efficacy is necessary.

Adult↗

[Cosmetic results of breast conserving therapy for breast carcinoma. Treatment results from the Heidelberg Radiation Clinic in the years 1984 to 1992].

PURPOSE: In this study we retrospectively analyzed local control, survival rate and late cosmetic results of women with early breast cancer receiving breast conserving therapy. PATIENTS AND METHODS: All patients (1984 through 1992) of the Department of Radio-Oncology (University of Heidelberg), who received breast conserving therapy consisting of conservative surgery followed by radiotherapy, were interviewed and asked to come. Subjective estimation of the cosmetic results of therapy was evaluated by means of a questionnaire. Cosmesis, circumferences and temperatures of different mammary regions were assessed and measured. Side effects and late sequelae were valued by the EORTC/RTOG-score. RESULTS: Mean follow-up time of 192 women (pT1: 71.9%, pT2: 28.1%) was 4.5 years (median: 4.0 years). 26.6% of them were nodal positive. Positive nodal status correlated with high tumor grading (p = 0.0001). Ten patients developed distant metastases; one of them subsequent to having suffered a loco-regional failure. Eight loco-regional failures occurred, 3 of them before radiotherapy (salvage). Following radiotherapy altogether 5 loco-regional failures (= 2.6%) were found; 3 women concerning were pre-, 2 postmenopausal. Three of these patients died, in 1 case occurred distant metastasis. Seventeen patients died, 3 of them presenting loco-regional failure, 8 of them showing distant metastasis. Sixty-four women were examined for cosmesis with the following result: a poor result was observed twice, a fair result 13 times, a good result 34 and an excellent result 15 times. Self-assessment was significantly better than observer's assessment. Third-degree late sequelae were found once, second-degree was seen 11 times, first-degree 38 times and no visible late sequelae were observed 14 times. The use of wedges was followed with borderline significance (p = 0.06) either by a better cosmesis and fewer late sequelae. Neither the type of surgery nor the width of the fields nor the quality of radiation (Co60 or 6 MVX) nor boost-application influenced the cosmetic result. Measured circumferences and distances showed no significant differences in the groups of the patients with poor or fair and good or excellent cosmesis. The temperature of the seized and contralateral breast showed no significant difference as well. With increasing distance from primary therapy the cosmetic results deteriorated. CONCLUSION: Breast conserving therapy consisting of conservative surgery followed by radiotherapy causes predominantly excellent to good cosmetic results combined with an acceptable amount of late side effects. The decreased rate of good and excellent cosmetic long-term results is biological interesting and requires further studies.

Aged↗

Operative or conservative treatment of the acutely torn anterior cruciate ligament in middle-aged patients. A follow-up study of 133 patients between the ages of 40 and 59 years.

In all, 133 patients with an acute rupture of the anterior cruciate ligament (ACL) were reviewed (aged 40 to 59 years). Average follow-up was 29 +/- 10 months. Thirty-one patients underwent conservative therapy, 35 patients were treated by primary suture, while in 67 the primary suture was augmented with the semitendinosus tendon. The patients with primary repair and semitendinosus tendon augmentation showed significantly better results according to OAK and Lysholm scores, the Lachman test, pivot-shift testing, and KT-1000 arthrometer measurements than those treated conservatively or with primary suture. The physical activity level was significantly higher in the patients with augmented ACL repair than in the conservatively treated patients. There was no significant difference between the patients with augmented ACL repair and conservative treatment in the assessment of range of motion, while the patients with primary suture had a significantly greater loss of flexion than those in the other two treatment groups. Increasing age was not found to have a negative effect on either operative or conservative treatment. The results indicate that patients between the ages of 40 and 59 years can be treated successfully by ACL surgery.

Adult↗

[Plastic surgical considerations of conservative weight loss in the treatment of morbid obesity].

BACKGROUND: According to the literature, conservative weight loss seems to be ineffective for morbidly obese subjects. Nevertheless, the significance of nonsurgical strategies for the treatment of morbid obesity is still unclear. PATIENTS: From 1999 to 2003, 197 reconstructive operations were performed on 120 morbidly obese patients. Initial body mass index (BMI) was higher than 35-40, and weight loss exceeded 40% of the original body weight. RESULTS: Gastric banding was performed in 66% of the patients; 34% reduced their body weight by conservative means. Conservative weight loss could be achieved at each level of BMI. CONCLUSION: Conservative weight loss is a valuable option for the treatment of morbid obesity in a selected group of patients. Condiolates candidates for conservative weight loss should be selected carefully by a multidisciplinary team with psychiatric expertise.

Abdominal Wall↗

[Possibilities and limits of functional conservative therapy of acute Achilles tendon ruptures].

According to sonographic criteria, 55 patients underwent surgical treatment with mobilisation in a lower leg plaster or conservative treatment with early mobilisation in heel pad (3 cm) shoes when an acute Achilles tendon rupture (ATR) was diagnosed. The follow-up period in 51 patients was 2.4 years (operated group = 28 patients, conservative group = 23 patients) with clinical examination and testing of isokinetic muscle strength in knee joint flexion. After surgical treatment, minor wound infections occurred in 10.6%. Reruptures occurred in 13% of the conservative group. Following conservative treatment, the rate of stress-related achillodynia was significantly higher (P = 0.019). In the operated group mean isokinetic muscle strength was 13.7% lower than in the uninvolved leg and decreased significantly with non-operative treatment to 75.3% (P = 0.012). We recommend surgical treatment of acute ATR. The indications for conservative treatment depend on the extent of the rupture (measured by ultrasound in the equinus position), the desired level of daily activity and the patient's degree of compliance.

Achilles Tendon↗

[Conservative treatment of idiopathic scoliosis with physical therapy and orthoses].

Opinions differ in the international literature about the efficacy of conservative approaches to scoliosis treatment. Because this divergence of opinion corresponds to a great discrepancy in the standards applied to conservative treatment methods, it is not astonishing that the results of conservative treatment as described in the literature also differ. Scoliosis normally does not have such dramatic effects that immediate surgery would be indicated.Moreover, it is clear from the published literature that it is the functional and physiological impairments of scoliosis patients--including pain, torso deformity, psychological disturbance, and pulmonary dysfunction--which require therapeutic intervention. In Germany the triad of outpatient physiotherapy, intensive inpatient rehabilitation, and bracing has proven effective in conservative scoliosis treatment.Indication, content, and results of the individual treatment procedures are described and discussed. The positive outcomes of this practice validate a policy of offering conservative scoliosis treatment as an alternative to patients, including those for whom surgery is indicated.

Adolescent↗

Highly conserved antigen-presenting function of CD1d molecules.

The lack of polymorphism of nonclassical antigen-presenting molecules has led to the proposal that they may carry out some conserved and essential antigen-presenting function. Although this is a plausible hypothesis, the major histocompatibility complex has undergone dramatic expansions and contractions through evolution, and there is surprisingly little evidence for interspecies conservation of nonclassical class I molecules. The CD1d molecule, by contrast, shows an extremely high degree of functional conservation between mice and humans, with regard to its interaction with the relatively invariant TCRs that are expressed by NK T cells. This conservation for CD1d recognition is observed either in the absence of exogenous Ag or together with a lipoglycan antigen. The close functional and phenotypic conservation of NK T cells, in mammalian species separated by approximately 50 million years, suggests an essential role in the immune system for CD1d recognition by NK T cells.

Animals↗

Bilateral reduction mammaplasty for immediate breast conservation surgery reconstruction and intraoperative radiotherapy: a preliminary report.

BACKGROUND: Breast conservation surgery and postoperative radiotherapy are widely accepted as the treatment of choice for patients with early breast cancer. Despite its oncologic benefits, the radiotherapy may cause unpredictable outcomes in soft tissues, especially in patients undergoing breast reconstruction. Described recently, intraoperative irradiation (IORT) has been indicated for selected patients as an alternative to radiotherapy with fewer adverse local effects. Clinical use of reduction mammaplasty (RM) techniques in oncologic breast surgery has been described previously. However, no previous studies have mentioned its application after breast conservation surgery and IORT. METHODS: The authors used RM to reconstruct a partial breast tissue defect secondary to breast conservation surgery followed by IORT treatment in a 46-year-old patient with an 11-mm invasive ductal carcinoma between the superior internal quadrants of the right breast. RESULTS: Satisfactory breast volume and shape were achieved, and no immediate or late complications were observed. After 2 postoperative years, no evidence of fat necrosis, tumor recurrence, or tissue volume loss was observed. CONCLUSION: The initial data indicate that RM in the setting of breast conservation surgery reconstruction and IORT is feasible. With appropriate patient selection, respecting indications and limitations, RM has its place among the various reconstructive techniques. Additional studies with larger clinical series and longer follow-up periods are necessary to analyze the precise IORT effects in patients submitted to immediate breast conservation surgery reconstruction.

Adult↗

Fracture dislocations of the cervical spine: a review of 106 conservatively and operatively treated patients.

We compared clinical outcomes following conservative treatment of subaxial fracture dislocations of the cervical spine and posterior fusion using bone grafts and interspinous Roger's wiring (Bohlman modification). We reviewed 106 patients: 51 were treated primarily surgically, and 55 treated conservatively served as historical controls. Those patients who neurologically recovered at least one Frankel grade had on average less displacement on discharge (1.3 mm vs 3.1 mm, p=0.04). Although anatomical outcomes were better in the operatively treated group (1.6 mm vs 2.9 mm displacement at end of follow-up, p=0.001), there was no difference in neurological recovery. Late neck pain correlated with residual displacement ( p=0.04) and was more common in the conservatively treated patients ( p=0.01). Time in hospital was shorter in the group with posterior fusions, and complication rates were similar to those found after conservative treatment. A significant number of the conservatively treated patients developed kyphotic deformity, and 29% needed later surgery because of chronic instability or unacceptable anatomical results.

Adolescent↗

Conservative treatment for small intestinal intussusception associated with Henoch-Schönlein's purpura.

PURPOSE: Emergency laparotomy is generally considered the appropriate course of action for small bowel intussusception associated with Henoch-Schönlein's purpura (HSP). In this paper, we define a conservative approach after witnessing spontaneous reduction of ileoileal invagination at laparotomy in a patient with HSP who had been on steroid therapy for renal involvement. METHODS: HSP was diagnosed by the appearance of a purpuric rash without thrombocytopenia. Intussusception was diagnosed by ultrasonography (USG) and plain abdominographs, which showed signs of obstruction, and clinical examination. Barium enema was used to treat ileocolic intussusceptions, and conservative therapy, consisting of nasogastric drainage, steroids, and intravenous fluid administration, was used to treat ileoileal intussusceptions. Emergency laparotomy was performed for the patients unresponsive to therapy within 24 h, those with peritonitis, and those with ileocolic invagination not able to be reduced by barium enema. RESULTS: Six children with an ileoileal intussusception and one with an ileocecal intussusception were studied. The average age was 6 years old. Apart from the initial patient in whom spontaneous reduction was seen at laparotomy, three others required emergency laparotomy; for ileocolic intussusception unable to be reduced by barium enema in one, for ileoileal invagination with peritonitis on admission in one, and for ileoileal intussusception unresponsive to conservative therapy in one. The other three patients were successfully treated by conservative therapy. CONCLUSION: Conservative therapy is feasible for HSP patients with small bowel intussusception as long as the time of onset is known, an ultrasonographic and X-ray diagnosis is confirmed, emergency operating facilities are available, and an experienced pediatric surgical team follows up the patients.

Child↗

Piagetian conservation of discrete quantities in bonobos (Pan paniscus), chimpanzees (Pan troglodytes), and orangutans (Pongo pygmaeus).

This study investigated whether physical discreteness helps apes to understand the concept of Piagetian conservation (i.e. the invariance of quantities). Subjects were four bonobos, three chimpanzees, and five orangutans. Apes were tested on their ability to conserve discrete/continuous quantities in an over-conservation procedure in which two unequal quantities of edible rewards underwent various transformations in front of subjects. Subjects were examined to determine whether they could track the larger quantity of reward after the transformation. Comparison between the two types of conservation revealed that tests with bonobos supported the discreteness hypothesis. Bonobos, but neither chimpanzees nor orangutans, performed significantly better with discrete quantities than with continuous ones. The results suggest that at least bonobos could benefit from the discreteness of stimuli in their acquisition of conservation skills.

Animals↗

The Internally Self-fertilizing Hermaphroditic Teleost Rivulus marmoratus (Cyprinodontiformes, Rivulidae) beta-Actin Gene: Amplification and Sequence Analysis with Conserved Primers.

To determine the ease and feasibility of amplifying the beta-actin gene in fish by the polymerase chain reaction (PCR), genomic DNAs of several fish (Rivulus, Southern top mouth minnow, common fat minnow, oily bitterling, carp, Far Eastern catfish, medaka, and European flounder) were extracted and used as a template with conserved primers, designed on the basis of high amino acid homology (approximately 98% or more). Among them, the self-fertilizing hermaphroditic fish Rivulus marmoratus was chosen for further characterization. After amplification of the Rivulus beta-actin PCR product with Taq polymerase, PCR product was subcloned to pCRII vector. After restriction enzyme mapping of Rivulus beta-actin gene, the amplified insert was sequenced using ALF Express automatic DNA sequencer with conserved internal primers. The R. marmoratus beta-actin gene consists of 1763 bp encoding 375 amino acids including 5 exons and 4 introns. The splicing and acceptance sites of the exon and intron boundaries of the Rivulus beta-actin gene were highly conserved with consensus sequences (GT/AG). The amino acid homology of R. marmoratus beta-actin to other species was high: 98.93% to human; 98.93%, Atlantic salmon; 98.93%, common carp; 98.93%, grass carp; 98.93%, zebrafish; 98.67%, medaka; and 98.40%, sea bream. To determine the expression of the R. marmoratus beta-actin gene in liver and ovary, reverse transcriptase-polymerase chain reaction was carried out with internal primers. In conclusion, these universal primers are successful in the rapid cloning of the fish beta-actin gene by PCR, based on a high homology of the beta-actin gene conserved through evolution. This approach will be applicable to the isolation of other beta-actin homologues in the investigation of phylogenetic comparisons of fish species, along with a possible application to cloning strategy in other conserved genes.

Journal Article↗