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As the common carp Cyprinus carpio and African catfish Clarias gariepinus affect biotic assemblages in aquatic ecosystems through their benthivory, their introduction has been considered an environmental concern. We compare the effects of common carp and African catfish on adjacent trophic level assemblages of plankton, periphyton, benthic macroinvertebrates and native tilapia in a pond ecosystem at the National Aquaculture Center, Zomba, Malawi. Four treatments were involved in the study: ponds with common carp (T1), ponds with African catfish (T2), ponds with both common carp and African catfish (T3), and ponds lacking both common carp and African catfish (T4). In all treatments, the endemic Shire tilapia Oreochromis shiranus was also present as part of the local macrofauna. Results showed that T1 had the most abundant phytoplankton but the lowest periphyton, zooplankton and benthic macroinvertebrate abundance and diversity. T4 had the least phytoplankton but the most abundant and diverse zooplankton, periphyton and benthic macroinvertebrates. There was no significant difference between T2 and T3 (both intermediate to T1 and T4) in terms of phytoplankton, periphyton and benthic macroinvertebrate abundance and diversity. Better water quality regime and increased biomass of native tilapia fish were observed in T3 ponds. We conclude that the farming of common carp in aquatic ecosystems containing African catfish may not adversely affect the environment and that the polyculture of African catfish and common carp can be adopted as a management strategy to mitigate the potential adverse effects of common carp.

Background To date, lactate dehydrogenase ( LDH) and S100B remain the most useful biomarkers for follow-up of melanoma patients. In recent years, indoleamine 2,3-dioxygenase ( IDO), an immunosuppressive enzyme, has been proposed as a new potential tumour biomarker for melanoma. However, further studies are needed to confirm the usefulness of IDO expression as an independent prognostic factor. Objective To explore the potential association between serum IDO levels and melanoma stage at diagnosis and recurrence, and to compare the results to those obtained with LDH and S100B. In addition, we also investigated a possible cut off for IDO level as a prognostic factor for overall survival. Methods IDO, LDH and S100B levels were measured in serum samples of 186 patients in all melanoma stages at diagnosis and twice a year thereafter. A cut-off point for IDO levels was calculated using receiver operating characteristic curves to explore the association between these levels and the likelihood of lymphatic spread. Survival curves were estimated for patient groups stratified by IDO level (higher or lower than the cut off), using the Kaplan-Meier method. Results At diagnosis, serum IDO levels were significantly higher in stages IB, II, III and IV, whereas S100B levels were significantly higher in stages III and IV, and LDH levels were only higher in stage IV. In relapsed patients, significant increases were found in levels of all three markers. Finally, overall survival was significantly longer in patients with IDO levels below a cut off of 1.65 μM at diagnosis than in those with higher levels (91.3 vs. 71.0% at 36 months). Conclusion In melanoma patients, serum IDO levels are significantly associated with disease stage, relapses and overall survival. These results indicate IDO could be a useful serum prognostic marker for melanoma. [ABSTRACT FROM AUTHOR]

Background: Recent evidence suggests that the alpha1-antitrypsin [AT] gene may play a role in the pathogenesis of the fibromyalgia syndrome [FMS]. The objective of the present study is to compare the AT gene frequency between FMS patients and the general population [GP] from the central region of the Asturias Province in Northern Spain. Method: The AT proteinase inhibitor phenotypes were characterized by isoelectric focusing on serum from a cohort of 250 individual FMS subjects, who fulfilled the American College of Rheumatology criteria for FMS, and on serum from a control cohort of 1,111 GP subjects. The FMS subjects [238 females and 12 males] were enlisted from an outpatient hospital clinic setting. The mean age of the FMS cohort was of 49.02 years. The GP control cohort [45 percent males and 55 percent females] was enrolled using an epidemiological technique of simple random sampling in the general population from the same region of Asturias. The GP sample size was 1,111, the mean age was of 46.2 years. Mean outcome measures were AT-PI phenotyping characterization [performed by isoelectric focusing] and AT serum concentration [measured by nephelometry]. Results: Calculated mean allele frequencies for PI*S and PI*Z [the two most frequent AT deficiency alleles] were 64 [95 percent confidence interval [CI]: 45-90] and 40 [CI: 25-62] per 1,000, respectively, for the FMS cohort, as compared with 100 [CI: 88-113] and 19.7 [CI: 14.5-26.6] per 1,000 for the GP cohort. Calculated prevalences [Hardy-Weinberg statistics formula] were 1/14 in FMS versus 1/29 in GP for MZ; 1/195 in FMS versus 1/254 in GP for SZ; and 1/625 in FMS versus 1/2,573 in GP for ZZ. For PI*Z, the calculated odd ratio among FMS versus GP was 2.06 [CI: 1.16-3.63]. A binomial proof [contrast hypothesis] stated that FMS AT-Z gene frequency differed significantly from the GP Z gene frequency [P = 0.007]. Conclusion: The most common AT severe-deficient allele [i.e., PI*Z] has been found with a two-fold higher frequency in the FMS cohort than in the GP cohort. The high odds ratio found for PI*Z indicates a significant difference for PI*Z frequency in the FMS cohort as compared with the GP cohort. Our findings suggest that AT deficiency might play an important role in FMS development and clinical expression in, at least, a subset of FMS subjects. [ABSTRACT FROM AUTHOR]

River impoundment is usually accompanied with consequences of alteration in the hydrological system and change in the biodiversity composition of the ecosystem. This study investigated the impact of the dams built on Challawa (that is, Challawa George-Dam) and Kano (that is, Tiga Dam) on the fish biodiversity of the reservoir and below-dam sections of the two rivers. Fish sampling was done using long lines, Malian traps, cast and gill nets from stations on the reservoir and below-dam sections of the rivers. Ten fish species were identified from the reservoir and the below-dam sections of Challawa River belonging to nine families and four orders. Fish communities of the reservoir and below-dam sections of Kano River consisted of 28 species belonging to 12 families and 7 orders. Results of the Shannon diversity index (H' ) indicated that the two reservoirs have relatively higher fish species diversity measures (that is, Challawa=1.948 & Kano=2.294) than the below-dam parts (that is, Challawa=1.833 & Kano=2.247) of their respective rivers. Non-metric Multidimensional Scaling (NMDS) analysis produced two-dimensional maps with stress values of 0.0554 and 0.0537, an indication that the model provided good representation of the original data in reduced-dimensional space. The ordination map indicated wide dissimilarities between fish communities of the impounded and below-dam sections. Furthermore, a one-way analysis of similarity indicated significant difference (P=0.0001) and high dissimilarities (R=0.643) between fish communities in the two sections of Challawa River and also in Kano River (P=0.001, R=0.929). Analysis of Similarity Percentage indicated 74.45% of the dissmilarities between fish communities in the two sections were cummulatively contributed by four species in Challawa River and 72.18% by five species in Kano River. The distinct differences in fish abundance and richness between the two sections is ascribed to increased ecosytem productivity often associated with the inundated portion of dammed river. It is recommended that more water flow across the dams should be encouraged as a mitigating measure to boost basin sizes of the rivers at the below-dam sections. [ABSTRACT FROM AUTHOR]

Oreochromis karongae is one of the three key Tilapia species locally known as 'Chambo' which is endemic to Lake Malawi. The species is favored by consumers and due to high demand its catches have significantly declined over time. Aquaculture holds the potential to supplement catches as well as produce seed for restocking purposes. However, seed production of O.karongae in artificial hatcheries has registered little success due to high egg and fry mortalities. Therefore, a study was conducted to compare the apparent effectiveness of three chemical egg disinfectants in an attempt to improve hatching success and reduce fry mortality in O. karongae in an artificial re-circulating incubation system at the National Aquaculture Center, Domasi, Malawi. Batches of 200 stage II eggs were immersed for 5 minutes in 50ml solutions of (1) 50mg/l Potassium Permanganate, (2) 500mg/l Formalin, (3) 1000mg/l Sodium Chloride, (4) 5000mg/l Sodium Chloride, while treatment (5) was a control without any chemical treatment. Each treatment was replicated three times in 1.2 L plastic incubation jars with continuous water flow rate of 0.17 l/s operated at 10% daily water replacement. There was significantly low total mortality and high hatchability in treatments (1), (2) and (3) than (4) and (5) (p<0.05). The results provided evidence that pre-incubation egg treatment using chemicals has potential to significantly reduce mortalities and increase fry production in an artificial re-circulating incubation system. It is recommended, based on the findings that lower concentrations of sodium chloride, being a safer and less toxic chemical can be used for disinfecting O.karongae eggs. Future studies should focus on undertaking a toxicity test with various levels of the chemical disinfectants to identify optimum doses. This should be coupled with microbiological assays to validate the apparent effectiveness found in this study and identify the key microbial species that are responsible for mortalities during incubation of O.karongae eggs in a re-circulating system. [ABSTRACT FROM AUTHOR]

In Africa, antibiotic residue investigations in animal food have primarily been focused on meat, neglecting farmed fish. This cross-sectional study conducted in Dar es Salaam, Tanzania, aimed to assess sulphonamide and tetracycline residues in farmed fish, comparing levels with Codex Alimentarius Commission's acceptable daily intake (ADI) and maximum residue limits (MRLs). A total of 84 farmed fish were sampled and analysed in the presence of tetracycline and sulphonamide residues. All samples were positive for sulphonamide residues (100%; n  = 84), and 2.4% ( n = 2) were positive for tetracycline and consequently also positive for both compounds. Tetracycline levels were below ADI and MRL, 28.5% ( n  = 24) surpassed the ADI, and 6% ( n  = 5) of the samples exceeded the MRL for sulphonamide. Regular monitoring of antibiotic residues in aquaculture products is crucial to mitigate health risks and expanding assessments to include other commonly used compounds is warranted.

Investigating the determinants of the reproductive biology of fishes is an essential component of fisheries research. Tilapia breeding patterns were investigated to determine the impact of non-native Oreochromis niloticus on the native congeneric Oreochromis macrochir in the upper Kabompo River in the Northwest of Zambia using the gonadosomatic index and the sex ratios. Oreochromis niloticus was the most abundant fish caught (221, 63.5%) than O .  macrochir (127, 36.5%). Results showed that the overall gonadosomatic index means of O .  macrochir in both sections were similar. Oreochromis macrochir bred in December and February-March, with no reproduction in June. However, O .  niloticus in the invaded section indicated all year reproduction through reduced spawning in May-June, with increased spawning activity in February-March. The sex ratio (females: males) was 1:1.3 and 1:1.7 for O .  niloticus and O .  macrochir , respectively, and both significantly deviated from the sex ratio of 1:1 (ꭓ 2  = 8.42 and 9.37, p  < .05). Our study has revealed that O .  niloticus was able to spawn across all sampled months with a 23% higher breeding population than O .  macrochir , which might explain the suppression in the abundance of native O .  macrochir . Due to the superior breeding patterns of O .  niloticus , fisheries, wildlife, and aquaculture practitioners need to make contingency plans to alleviate its impacts further downstream of the Kabompo River., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Invasive alien species have been revealed to drastically alter the structure of native communities; however, there is scarce information on whether taxonomic and functional spaces occupied by native species are equally filled by exotic species. We investigated the diversity of native species to understand the impact of exotic Oreochromis niloticus in the upper Kabompo River, northwest of Zambia using taxonomic and functional diversity indices. To achieve this, two tests were performed (Test 1, compared natives in invaded and uninvaded sections; Test 2, compared natives in invaded section). A total of 17 species were collected for functional diversity computation, out of which fourteen (14) functional trait measurements linked to feeding, locomotion, and life history strategy were taken. Findings revealed that taxonomic and functional diversity values changed with invasion in both tests. Taxonomic diversity was 15% more in invaded than uninvaded sections in Test 1 and was not consistent across sampling points of invaded section in Test 2. Invaded areas were taxonomically less diverse, but functionally diverse in both tests. The analysis of similarity and nonmetric multidimensional scaling revealed no difference in Bray-Curtis similarity assemblages in both tests. Our findings revealed that exotic species more often occupy unfilled gaps in the communities often occupied by the native species; this is achieved by occupying functional spaces. Overall, changes in taxonomic and functional diversity of native species documented here partially confirmed impacts of O . niloticus invasion. Therefore, we recommend a multifaceted approach to assess cumulative impacts of invasion on native species., Competing Interests: None declared., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Local adaptation to the littoral and pelagic zones in two cichlid haplochromine fish species from Lake Kivu was investigated using morphometrics. Cranial variation and inferred jaw mechanics in both sexes of the two species across the two habitat types were quantified and compared. Comparisons of littoral versus pelagic populations revealed habitat-specific differences in the shape of the feeding apparatus. Also, kinematic transmission of the anterior jaw four-bar linkage that promotes greater jaw protrusion was higher in the pelagic zone than in the littoral zone for both species. Inferred bite force was likewise higher in pelagic zone fish. There were also sex-specific differences in craniofacial morphology as males exhibited longer heads than females in both habitats. As has been described for other cichlids in the East African Great Lakes, local adaptation to trophic resources in the littoral and pelagic habitats characterizes these two Lake Kivu cichlids. Similar studies involving other types of the Lake Kivu fishes are recommended to test the evidence of the observed trophic patterns and their genetic basis of divergences., Competing Interests: The authors have no conflict of interest to declare., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Tooth shape is used to differentiate between morphologically similar species of vertebrates, including fish. This study aimed to quantify tooth shape of three sympatric species: Haplochromis kamiranzovu , H. insidiae , and H. astatodon endemic to Lake Kivu, whose existing identification criteria are currently only qualitative. A quantitative tooth shape analysis was performed based on digitized tooth outline data with a subsequent elliptic Fourier analysis to test for differences among the three species. We looked at crown shape and size differences within H. kamiranzovu and H. insidiae at geographical, habitat, and gender levels. No comparison at habitat level was done for H. astatodon because it is found only in littoral zone. The analysis revealed significant tooth shape differences among the three species. Haplochromis astatodon had a significantly longer major cusp height and a longer and larger minor cusp than that of H. insidiae. It had also a longer major cusp height and a longer and larger minor cusp than that of H. kamiranzovu . Tooth shape differences of H. kamiranzovu and H. insidiae species were not significantly different between littoral and pelagic fish ( p  > .05) while differences were significant between southern and northern Lake Kivu populations ( p  < .05). Tooth sizes in H. kamiranzovu and H. insidiae were significantly different, both in height and width as well as in their ratios, and this was true at sex and geographic levels ( p  < .05), but not at habitat level ( p  > .05). Tooth shape was also significantly different with sharp teeth for males compared with females of southern populations versus northern ones. These shape- and size-related differences between sexes suggest differences in the foraging strategies toward available food resources in the lake habitat. Further research should explain the genetic basis of the observed pattern., Competing Interests: The authors have no conflict of interest to declare., (© 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Background: To date, lactate dehydrogenase (LDH) and S100B remain the most useful biomarkers for follow-up of melanoma patients. In recent years, indoleamine 2,3-dioxygenase (IDO), an immunosuppressive enzyme, has been proposed as a new potential tumour biomarker for melanoma. However, further studies are needed to confirm the usefulness of IDO expression as an independent prognostic factor., Objective: To explore the potential association between serum IDO levels and melanoma stage at diagnosis and recurrence, and to compare the results to those obtained with LDH and S100B. In addition, we also investigated a possible cut off for IDO level as a prognostic factor for overall survival., Methods: IDO, LDH and S100B levels were measured in serum samples of 186 patients in all melanoma stages at diagnosis and twice a year thereafter. A cut-off point for IDO levels was calculated using receiver operating characteristic curves to explore the association between these levels and the likelihood of lymphatic spread. Survival curves were estimated for patient groups stratified by IDO level (higher or lower than the cut off), using the Kaplan-Meier method., Results: At diagnosis, serum IDO levels were significantly higher in stages IB, II, III and IV, whereas S100B levels were significantly higher in stages III and IV, and LDH levels were only higher in stage IV. In relapsed patients, significant increases were found in levels of all three markers. Finally, overall survival was significantly longer in patients with IDO levels below a cut off of 1.65 μM at diagnosis than in those with higher levels (91.3 vs. 71.0% at 36 months)., Conclusion: In melanoma patients, serum IDO levels are significantly associated with disease stage, relapses and overall survival. These results indicate IDO could be a useful serum prognostic marker for melanoma., (© 2016 European Academy of Dermatology and Venereology.)

Breast cancer incidence and mortality rates are similar in low resource settings like Tanzania. Structural and sociocultural barriers make late presentation typical in such settings where treatment options for advanced stage disease are limited. In the absence of national programmes, stand-alone screening campaigns tend to employ clinical models of delivery focused on individual behaviour and through a disease specific lens. This paper describes a case study of a 2010 stand-alone campaign in Tanzania to argue that exclusively clinical approaches can undermine screening efforts by premising that women will act outside their social and cultural domain when responding to screening services. A focus on sociocultural barriers dictated the approach and execution of the intervention. Our experience concurs with that in similar settings elsewhere, underscoring the importance of barriers situated within the sociocultural milieu of societies when considering prevention interventions. Culturally competent delivery could contribute to long-term reductions in late stage presentation and increases in treatment acceptance. We propose a paradigm shift in the approach to stand-alone prevention programmes.

Background and Objective: Head and neck squamous cell carcinoma (HNSCC) is a malignant tumor of epithelial origin, which currently represents a major socio-sanitary problem since about 500,000 new cases are reported worldwide every year. In Spain, the HNSCC incidence exceeds 40 cases out of 100.000 individuals/year. HNSCC mortality is closely related to both local relapse and regional or distant lymphatic metastasis. Any reliable tumor-specific biomarker to predict preoperatively HNSCC relapse or lymphatic spread is not currently available. To date, several diagnostic procedures (imaging technologies, biochemical markers) have not shown enough potential to predict the presence of lymph node metastasis. There are new tumor markers related to the metastatic spread that have not been yet evaluated in HNSCC. The main goals of the present study was to determine an specific and reliable serum biomarkers pattern for HNSCC diagnosis, and to predict the HNSCC evolution before surgical therapy by developing appropriate biomarkers related to local relapse and lymphatic metastasis., Material and Method: Thirty nine serum samples of HNSCC patients were collected during every neoplasm resection. Another 10 serum samples were collected from healthy individuals as a control group. Selected serum biomarkers were: soluble E-cadherine, metalloproteinases (MMP) 2, MMP-9, active MMP-13; and Ac anti-p53., Results: High serum levels of soluble E-cadherine, MMP-9, active MMP-13, and presence Ac anti-p53 were found to be significantly different from those in the control group. There was a statistic association with MMP-2 levels below 290 ng/ml and poor survival. We also found significant differences between active MMP-13 (levels > 685 pg/ml) and the presence of anti-p53 antibodies with the presence of lymph node metastasis. The multimarker analysis using both tumor markers provided the better sensibility (76%) and specifity (100%) values., Conclusions: The combined determination and valuation of tumor markers could improve the potential diagnosis of lymph node metastasis in HNSCC.

The apparent inter-lake morphological similarity among East African Great Lakes' cichlid species/genera has left evolutionary biologists asking whether such similarity is due to sharing of common ancestor or mere convergent evolution. In order to answer such question, we first used Geometric Morphometrics, GM, to quantify morphological similarity and then subsequently used Amplified Fragment Length Polymorphism, AFLP, to determine if similar morphologies imply shared ancestry or convergent evolution. GM revealed that not all presumed morphological similar pairs were indeed similar, and the dendrogram generated from AFLP data indicated distinct clusters corresponding to each lake and not inter-lake morphological similar pairs. Such results imply that the morphological similarity is due to convergent evolution and not shared ancestry. The congruency of GM and AFLP generated dendrograms imply that GM is capable of picking up phylogenetic signal, and thus GM can be potential tool in phylogenetic systematics.