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Operationalizing Local Ecological Knowledge for Aquatic Biodiversity Conservation: A Systematic Review and Management Framework.

Effective conservation and management of aquatic biodiversity is severely constrained by the absence of long-term ecological data in small-scale, tropical, and data-poor fisheries, where roughly one-quarter to one-third of freshwater fish species and 37.5% of elasmobranchs are threatened with extinction once Data Deficient species are accounted for. Conventional monitoring and stock-assessment tools are often financially and technically inaccessible in these systems, leaving managers without the evidence needed to prioritize conservation action or implement precautionary governance. Local Ecological Knowledge (LEK) is a largely underutilized resource for natural resource management that can provide temporal depth, spatial resolution, and species-specific ecological insights unavailable from scientific records. We conducted a systematic review and bibliometric synthesis of 60 peer-reviewed studies (1997-2025) applying LEK to assess fish conservation status, examining how, where, and through what methods this knowledge has been used. Our analysis identifies four complementary pathways through which LEK informs conservation management: reconstructing multi-decadal population changes, documenting spatial contraction and habitat loss, detecting extreme rarity and local extirpation, and characterizing intrinsic sensitivity to exploitation based on life-history traits. Despite growing methodological rigor, freshwater systems and African fisheries remain critically underrepresented, and formal integration of LEK into fisheries governance and biodiversity assessment remains the exception rather than the rule. We propose a practical three-stage framework to operationalize LEK within existing management and conservation systems. Recognizing fishing communities as legitimate co-producers of ecological knowledge is both scientifically necessary and an equity imperative for achieving global biodiversity commitments under the Kunming-Montreal Global Biodiversity Framework.

Biodiversity↗

Outcome of conservative management of small renal stones in prepubertal children.

INTRODUCTION: Renal stones are relatively uncommon in the pediatric population. This study aimed to evaluate the utility of conservative management of small renal stones in prepubertal children. PATIENTS AND METHODS: A retrospective chart review was conducted for children (&#x2264;12 years old) with small renal stones (3-10 mm) from 2016 to 2023 who underwent conservative management. Management included periodic renal ultrasonography, every 6 months, in addition to good hydration. Stones were confirmed by two consecutive ultrasounds. We recorded the patient's demographics and ultrasound findings (stone side, size, laterality, location, number, and associated hydronephrosis). Surgical intervention was indicated if recurrent loin pain, recurrent UTI, or worsening hydronephrosis (obstructing stone). Nephrolithiasis was considered resolved if stones were not visualized on 2 consecutive ultrasounds. Moreover, we evaluated conservative management outcomes for those presented during infancy (<12 months) versus later. RESULTS: We included 52 patients (65renal units) who presented at a median age of 46.1months (5.3-155.1). Seventy-five percent of patients had incidental renal stones. The median stone size was 4 mm (3-10). Forty-six percent of stones were in the lower calyx. The majority (70.8 %) had no hydronephrosis at presentation. During a median follow-up of 39months, 15patients with 17units (26.2 %) were documented stone-free. Ten patients (19.2 %) had symptomatic stone events, all measured &#x2265;4 mm. Of them, 6 patients (6 units) underwent surgical interventions, and 4 patients (4 units) experienced complications. A ROC curve analysis identified a stone size cutoff of 4 mm (sensitivity 100 % and 29 % specificity) that could be associated with symptomatic stone events. Using a multivariate Cox regression model, stone size was the only significantly associated factor with subsequent surgical intervention (p = 0.007). 19 % (10patients,12units) presented during infancy. Notably, the incidence of stone-free rate was significantly higher during infancy compared to older children (58.3 % vs 18.9 %,respectively). DISCUSSION: During a 39-month follow-up, 4 patients developed complications (2recurrent pain and 2 experienced UTI), supporting the safety of conservative management of small renal stones. This study is limited due to its retrospective design and the reliance on ultrasound as the main imaging method. To minimize that, all ultrasound images were carefully reviewed by two pediatric urologists. Moreover, renal stones were confirmed using strict criteria, which required detection in two consecutive ultrasounds. CONCLUSION: Although 26.2 % of units had spontaneously resolved nephrolithiasis, surgical intervention was only required in 11.5%of patients, all of whom had renal stones&#x2265;4 mm. Infants had higher spontaneous resolutions without complications, suggesting that conservative management may be especially effective in this subgroup.

Humans↗

Analysis of TFIIH subunit through isolation of the gene from Schizosaccharomyces pombe corresponding to that of Saccharomyces cerevisiae SSL1, reveals the presence of conserved structural motifs.

We isolated a Schizosaccharomyces pombe (Sz. pombe) gene encoding the counterpart of the TFIIH subunit Homo sapiens (H. sapiens) p44 and Saccharomyces cerevisiae (S. cerevisiae) SSL1, and we named this gene product p47. Contrary to the case of SSL1, which is an essential gene of S. cerevisiae, p47 is not essential for the viability of Sz. pombe. The deduced amino acid sequence revealed that this TFIIH subunit is highly conserved during evolution. Comparison of the primary structures revealed differences in the predicted positions of introns in the Caenorhabditis elegans (C. elegans) gene encoding the p47 counterpart found during the genome project. A charged cluster in the N-terminal region is present in the two yeasts. Two putative zinc-binding motifs, an extended C2H2 zinc finger with a 'C8 motif' and a second putative zinc-binding motif common to the two TFIIH subunits, were also found, the former being completely conserved. The latter motif consists of five cysteine residues and is also present in hp44, SSL1 and another TFIIH subunit, human p34 (hp34). Since one zinc atom can bind to four ligands in zinc-binding motifs, the conservation of cysteine residues was given attention. This motif is completely conserved in p47 homologues derived from the four species. As one cysteine residue is not conserved among the homologues of hp34, the consensus of this motif is concluded to be Cys X2-Cys-X(10,12)-Cys-X2-Cys. This nucleotide sequence has been deposited in the GenBank Data Library under Accession Number AF017646.

Amino Acid Sequence↗

Murine Hoxc-9 gene contains a structurally and functionally conserved enhancer.

Reporter gene analysis of the Hoxc-9 genomic region in transgenic mice allowed us to identify a positional enhancer in the Hoxc-9 intron that drives expression in the posterior neural tube of midgestation mouse embryos in a Hoxc-9-related manner. Sequence comparison to the chicken Choxc-9 intron revealed the existence of two highly conserved sequence elements (CSEs) in a similar spatial arrangement. These structural similarities in the mammalian and avian lineage are mirrored by conserved function of the chicken Choxc-9 intron in transgenic mice. Deletion analysis of the two introns suggests that full activity of both enhancers depends on cooperation between the two CSEs located close to the respective 5' and 3' splice sites. Following the paradigm of phylogenetically conserved developmental control mechanisms, the Hoxc-9 intragenic enhancer was tested in Drosophila. Our data show that the mouse Hoxc-9 enhancer acts in a conserved fashion in transgenic flies, conferring posteriorly restricted reporter gene expression to the developing central nervous system in third instar larvae. This finding indicates that the Hoxc-9 intragenic enhancer is involved in transcriptional regulatory circuits conserved between vertebrates and arthropods.

Animals↗

Conserved region mutations of the p53 gene are concentrated in distal colorectal cancers.

Distal colorectal cancers, especially those in the rectum, are more aggressive and more commonly recurrent than proximal cancers. We studied the possible relationship between p53-gene mutation type and location of the tumour, since mutations in the conserved areas of the p53 gene have been suggested to result in a poorer outcome of colorectal cancer than mutations outside these areas. Exons 5 to 8 of the p53 gene were studied in specimens from 72 colorectal-cancer patients. Polymerase-chain-reaction-amplified products of tumour DNA were analyzed by automated direct sequencing. Of the mutations detected in distal cancers, 71% were located in conserved regions of the gene, while only 42% of the mutations in proximal cancers were in these areas. In rectal cancers, 81% of the mutations were located in conserved regions. The tumours with mutations in the conserved regions were more often poorly differentiated (23%) than those with other mutations (0%). Our results indicate that mutations in the conserved regions of the p53 gene accumulate in distal but not in proximal tumours. This difference may be related to the more aggressive behaviour and to different aetiological factors associated with distal tumours.

Adult↗

The BPI/LBP family of proteins: a structural analysis of conserved regions.

Two related mammalian proteins, bactericidal/permeability-increasing protein (BPI) and lipopolysaccharide-binding protein (LBP), share high-affinity binding to lipopolysaccharide (LPS), a glycolipid found in the outer membrane of gram-negative bacteria. The recently determined crystal structure of human BPI permits a structure/function analysis, presented here, of the conserved regions of these two proteins sequences. In the seven known sequences of BPI and LBP, 102 residues are completely conserved and may be classified in terms of location, side-chain chemistry, and interactions with other residues. We find that the most highly conserved regions lie at the interfaces between the tertiary structural elements that help create two apolar lipid-binding pockets. Most of the conserved polar and charged residues appear to be involved in inter-residue interactions such as H-bonding. However, in both BPI and LBP a subset of conserved residues with positive charge (lysines 42, 48, 92, 95, and 99 of BPI) have no apparent structural role. These residues cluster at the tip of the NH2-terminal domain, and several coincide with residues known to affect LPS binding; thus, it seems likely that these residues make electrostatic interactions with negatively charged groups of LPS. Overall differences in charge and electrostatic potential between BPI and LBP suggest that BPI's bactericidal activity is related to the high positive charge of its NH2-terminal domain. A model of human LBP derived from the BPI structure provides a rational basis for future experiments, such as site-directed mutagenesis and inhibitor design.

Acute-Phase Proteins↗

Molecular cloning of a Schizosaccharomyces pombe cDNA encoding lanosterol synthase and investigation of conserved tryptophan residues.

A Schizosaccharomyces pombe cDNA encoding lanosterol synthase was cloned by complementing a Saccharomyces cerevisiae lanosterol synthase mutant. The predicted 83-kDa protein is 54-58% identical to other lanosterol synthases. The previously known lanosterol synthases contain 229 conserved residues, which should encompass the catalytically essential amino acids. This number is decreased dramatically by including the Sc. pombe lanosterol synthase in the analysis; 42 residues are no longer conserved and therefore are catalytically nonessential. We have begun mutagenic studies to identify catalytic residues from the remaining conserved residues. Mutant Sa. cerevisiae lanosterol synthase genes were generated in which phenylalanine was specifically substituted for conserved tryptophan residues. All of the resultant mutant enzymes retained the ability to complement the Sc. cerevisiae lanosterol synthase mutant, suggesting that these conserved tryptophan residues are not catalytically essential.

Amino Acid Sequence↗

A highly conserved major histocompatibility complex class I-related gene in mammals.

We report here a cDNA sequence of a murine homolog of the human major histocompatibility complex (MHC) class I-related gene, MR1. The analyses revealed unprecedentedly high conservation of MR1 in the alpha1 and alpha2 domains (corresponding to the peptide-binding domains in the classical MHC class I molecules) between human and mouse (predicted amino acid identity: 90 and 89% for the alpha1 and alpha2 domain, respectively), compared to MHC class I and other class I molecules. On the other hand, conservation in the alpha3 domain (73%) is comparable to those of others, suggesting domain-specific conservation of MR1. The localization of the mouse MR1 gene was determined to be chromosome 1H1, which corresponds to the human chromosomal region where the human MR1 gene is located (chromosome 1q25). High conservation of MR1 among mammals suggests that MR1 may be involved in critical conserved biological function(s).

Amino Acid Sequence↗

A conserved cluster of homeodomain binding sites in the mouse Hoxa-4 intron functions in Drosophila embryos as an enhancer that is directly regulated by Ultrabithorax.

The evolutionary conservation of the homeodomains suggests that their in vivo DNA binding sites may also be conserved between vertebrates and invertebrates. The regulatory function of the mouse Hoxa-4 and Hoxb-4 introns were analyzed in Drosophila since they both contain a cluster of three homeodomain binding sites, the HB1 element, which was also found in the introns of other Hox genes ranging from fish to humans as well as in the Ultrabithorax (Ubx) and decapentaplegic (dpp) genes of Drosophila. The enhancer of the Hoxa-4 intron was found to respond to several homeobox genes activating a lacZ reporter gene in particular cells of the epidermis in Drosophila embryos. The enhancer activity was found to be similar to previously described autoregulatory elements of Deformed (Dfd), the Drosophila homolog of Hoxa-4, but additional expression was observed in more posterior segments activated by Ubx and repressed by abdominal-A (abd-A). Point mutations in the homeodomain binding sites in HB1 abolished the enhancer activity. A second site suppression experiment showed that UBX interacts directly with the HB1 element. When the HB1 element in the Hoxa-4 intron was replaced by that of the mesodermal enhancer of dpp, which was previously shown to be directly controlled by Ubx, Ubx-dependent activation was retained, but repression by abd-A was lost. The same result was obtained when the third binding site of HB1 was altered, suggesting that this site is responsible for abd-A-dependent repression. Finally, deletion of potential cofactor binding sites flanking the HB1 element that are also conserved in the medaka, chicken, and mouse genes revealed that they are important for enhancer function in Drosophila and that the Dfd-dependent and the Ubx-dependent expression requires different sites. The evolutionary and functional conservation of the HB1 elements indicates that not only the homeodomains but also some of their in vivo binding sites are conserved between vertebrates and invertebrates.

Animals↗

The complete sequences of the galago and rabbit beta-globin locus control regions: extended sequence and functional conservation outside the cores of DNase hypersensitive sites.

The locus control region (LCR) of mammalian beta-globin genes covers at least 17 kb at the 5' end of the gene cluster and has been implicated in chromatin domain opening, enhancement, and insulation from neighboring sequences. Functional dissection of the LCR has defined the minimal cores for four of the five major DNase hypersensitive sites (HSs) that mark this regulatory region. To examine fully the patterns of conserved sequences in the mammalian homologs to the beta-globin LCR, we determined the complete DNA sequence of the galago beta-globin LCR and completed previously unsequenced regions of the rabbit LCR. Simultaneous alignment of these sequences with the human, goat, and mouse LCRs revealed conserved sequences (phylogenetic footprints) detected using three largely independent methods. The most highly conserved segments are found both within the HS cores and in some but not all regions flanking the cores. These results argue for an extended pattern of well-conserved sequences, many of which lie outside the minimal cores, and we show that a key sequence required for domain opening by the region including HS3 maps about 1 kb 5' to the minimal core. Differential phylogenetic footprints, containing sequences conserved in nonhuman mammals but not in humans, are found primarily around HS3, consistent with some species-specific differences in function that may be important for differences in hemoglobin switching during development.

Animals↗

Effective use of sequence correlation and conservation in fold recognition.

Protein families are a rich source of information; sequence conservation and sequence correlation are two of the main properties that can be derived from the analysis of multiple sequence alignments. Sequence conservation is related to the direct evolutionary pressure to retain the chemical characteristics of some positions in order to maintain a given function. Sequence correlation is attributed to the small sequence adjustments needed to maintain protein stability against constant mutational drift. Here, we showed that sequence conservation and correlation were each frequently informative enough to detect incorrectly folded proteins. Furthermore, combining conservation, correlation, and polarity, we achieved an almost perfect discrimination between native and incorrectly folded proteins. Thus, we made use of this information for threading by evaluating the models suggested by a threading method according to the degree of proximity of the corresponding correlated, conserved, and apolar residues. The results showed that the fold recognition capacity of a given threading approach could be improved almost fourfold by selecting the alignments that score best under the three different sequence-based approaches.

Amino Acid Sequence↗

Complete sequence of Leishmania RNA virus 1-4 and identification of conserved sequences.

In order to understand the coding strategies and identify potential cis-acting sequences in Leishmania RNA virus 1 (LRV1), a complete cDNA sequence was obtained for LRV1-4 and compared to the sequence reported for LRV1-1. The results show that the 5' end of LRV1 is conserved at the nucleotide level while open reading frames (ORFs) 2 and 3 are conserved at the amino acid level. A simple translation initiation consensus sequence is conserved at the 5' end of ORF2 but absent from ORF3, consistent with a possibility that ORF3 is expressed as a gag-pol fusion protein. Comparison of secondary structure predictions obtained for both isolates identified nucleotide sequences capable of forming conserved stem-loops at the virus termini and in the putative frameshift region between ORF2 and ORF3. Although direct evidence is lacking, the appearance of compensatory nucleotide substitutions suggests that the structures may form in vivo. Possible functions for the conserved structures are discussed.

Amino Acid Sequence↗

HomologyPlot: searching for homology to a family of proteins using a database of unique conserved patterns.

A new database of conserved amino acid residues is derived from the multiple sequence alignment of over 84 families of protein sequences that have been reported in the literature. This database contains sequences of conserved hydrophobic core patterns which are probably important for structure and function, since they are conserved for most sequences in that family. This database differs from other single-motif or signature databases reported previously, since it contains multiple patterns for each family. The new database is used to align a new sequence with the conserved regions of a family. This is analogous to reports in the literature where multiple sequence alignments are used to improve a sequence alignment. A program called HomologyPlot (suitable for IBM or compatible computers) uses this database to find homology of a new sequence to a family of protein sequences. There are several advantages to using multiple patterns. First, the program correctly identifies a new sequence as a member of a known family. Second, the search of the entire database is rapid and requires less than one minute. This is similar to performing a multiple sequence alignment of a new sequence to all of the known protein family sequences. Third, the alignment of a new sequence to family members is reliable and can reproduce the alignment of conserved regions already described in the literature. The speed and efficiency of this method is enhanced, since there is no need to score for insertions or deletions as is done in the more commonly used sequence alignment methods. In this method only the patterns are aligned. HomologyPlot also provides general information on each family, as well as a listing of patterns in a family.

Amino Acid Sequence↗

Residential water consumption, motivation for conserving water and the continuing tragedy of the commons.

This paper explores the effect of the perception of externalities (PE) on residential water consumption. Externalities occur when individuals make decisions that harm others, without concern for the impact or feeling a need to compensate for the harm. The aim of this study was to investigate whether PE affects people's motivation to conserve water, and, consequently, the practice of residential water consumption. Two hundred eighty Mexican citizens responded to a questionnaire investigating how they perceived that other individuals in their community wasted water. Respondents were also asked about their motives to conserve water, and direct observations of individual water consumption were recorded. Results were processed within a structural equations model, which revealed that motives to conserve water significantly inhibit water consumption. Since the perception of extemalities also inhibits conservation motives, the resulting effect of PE on water consumption is positive. This result means that the more people perceive that others waste water, the less their conservation motives, and, therefore, the more their own water consumption.

Adult↗

Effectiveness of voluntary habitat stewardship in conserving grassland: case of operation burrowing owl in Saskatchewan.

There have been no published performance evaluations of nongovernmental, voluntary habitat stewardship programs. The Operation Burrowing Owl (OBO) stewardship program, initiated in 1987, was evaluated for its effectiveness in conservation of grassland habitat during 1986-1993. The 108 OBO sites from 1987 to 88 and 98 randomly selected non-OBO sites that were grassland in 1986 in the Regina-Weyburn, Saskatchewan study area were classified by size and agricultural soil suitability. By 1993, 41 (38%) of the 108 OBO sites had been withdrawn from the program. The 1986 area of grassland was compared with grassland area calculated from digitized 1993 LANDSAT imagery. A correction for satellite inaccuracies was determined. Grassland retention in 1993 was significantly higher at OBO sites (66%) than at random sites (49%), demonstrating that the OBO voluntary program effectively conserved habitat. Also, grassland retention was significantly lower on sites with better agricultural soils, and for sites <12 ha in size. Site type (OBO or random), size and their interaction, followed by agricultural soil suitability, had the greatest effects on grassland retention. During an era of accelerated grassland loss, OBO strongly and positively (statistically significant) affected conservation of grassland sites most at risk: sites <12 ha in size and with good to excellent agricultural soils. This suggests that grassland conservation efforts focus on vulnerable sites (small size and/or good agricultural soils) to provide nesting habitat for burrowing owls. Our study demonstrates that a voluntary stewardship program can significantly increase conservation of habitat.

Agriculture↗

Do open-cycle hatcheries relying on tourism conserve sea turtles? Sri Lankan developments and economic-ecological considerations.

By combining economic analysis of markets with ecological parameters, this article considers the role that tourism-based sea turtle hatcheries (of an open-cycle type) can play in conserving populations of sea turtles. Background is provided on the nature and development of such hatcheries in Sri Lanka. The modeling facilitates the assessment of the impacts of turtle hatcheries on the conservation of sea turtles and enables the economic and ecological consequences of tourism, based on such hatcheries, to be better appreciated. The results demonstrate that sea turtle hatcheries serving tourists can make a positive contribution to sea turtle conservation, but that their conservation effectiveness depends on the way they are managed. Possible negative effects are also identified. Economic market models are combined with turtle population survival relationships to predict the conservation impact of turtle hatcheries and their consequence for the total economic value obtained from sea turtle populations.

Animals↗

Influence of targets and assessment region size on perceived conservation priorities.

We used an existing conservation opportunity area (OA) data layer for four contiguous ecological subsections within the Ozark Highlands to quantitatively evaluate the influence of conservation targets and assessment region size on conservation priorities. OAs are natural and seminatural land-cover patches that are away from roads and away from patch edges. To evaluate the influence of targets, we assigned a priority score to each OA polygon for each of five different conservation targets, including land-cover patch size, landform representation, target vertebrate richness, target breeding bird richness, and target land cover. The top-scoring OAs for each target were added to an OA selection set for that target until 50% of the study area was chosen. These five OA selection sets were overlain to quantify overlap in priorities. Only 1.6% of the study area, or 2.1% of all OA polygons, was selected by all five targets. To evaluate the influence of assessment region size, we compared results of priority ranking of OAs relative to the entire study area against a merged set of priority rankings established separately relative to each of the four subsections within the study area. When high-priority OAs were added until 25% of the region was within the selection set for each of the five targets, the sets based on the whole study area versus each subsection evaluated separately overlapped from 45.4% to 81.9%. Thus, perceived priorities of conservation assessments are strongly influenced both by the targets that are evaluated and by the size of the assessment region.

Conservation of Natural Resources↗

Building the capacity of grassroots conservation organizations to conduct participatory evaluation.

Stakeholder participation has become a key factor in the success of grassroots conservation and natural resource management programs. Yet the majority of program evaluations are conducted by external consultants for the purposes of accountability, rather than program improvement. Too often, systematic evaluations of conservation programs are not conducted at all. The objective of this study was to build the capacity of a grassroots conservation organization to conduct participatory evaluation, involving project stakeholders in the design, implementation, and use of evaluation. The study applied a conceptual model for participatory evaluation to the Wildlife Clubs of Kenya (WCK), the largest grassroots conservation program for youth in Africa, involving more than one million youth since 1968. Seven trainings in participatory evaluation were conducted with WCK staff, teachers, and community members. The 120 participants, representing nine WCK regions with 800 clubs, showed a significant increase in attitudes and knowledge regarding evaluation, as reflected by mean test scores before and after training. To institutionalize evaluation at WCK, existing organizational practices were assessed and used as a foundation for developing an evaluation system. Based on club competitions, a new evaluation initiative was launched called the WCK Incentive Program. Participants in all seven workshops identified indicators and sources of evidence for this evaluation system, which now serves as a basis for rewarding outstanding performance in WCK. This study revealed the importance of incentives for evaluation, the need to build on existing structures to promote organizational learning, and the necessity for the conservation community to commit resources to capacity building in participatory evaluation.

Animals↗