Introduction: Osteonecrosis of the femoral head (ONTF) is a debilitating condition. Several treatments have been proposed with controversial results. The aim of our study was to evaluate treatment by surgical drilling...Introduction: Osteonecrosis of the femoral head (ONTF) is a debilitating condition. Several treatments have been proposed with controversial results. The aim of our study was to evaluate treatment by surgical drilling coupled with in situ cancellous grafting. Materials and methods: Our study was a case-control study conducted at Brazzaville University Hospital from 1st January 2018 to 31 December 2023. It compared two groups of patients with ONTF: non-operated (13 patients, 20 hips) and operated (22 patients, 35 hips). We used the visual digital scale (VDS) for pain assessment, the Merle D’Aubigne-Postel (MDP) scoring system for clinical and functional assessment, and the evolution of necrosis. Results: The group of non-operated patients had a mean age of 35.69 ± 3.4 years, no improvement in pain with an EVN above seven at the last recoil and a mean global MDP score falling from 12.7 before offloading to 10.13 at one year. The group of patients operated on had a mean age of 37.86 ± 7.02 years, a significant reduction in pain (p = 0.00004) and a significantly increased MDP score (p = 0.0034). A comparison of the two groups of patients showed significant stabilization of the necrotic lesions in the operated patients (p = 0.00067), with better satisfaction in the same group. Conclusion: Surgical drilling combined with grafting in the treatment of early-stage ONTF has improved progress in our series. The technique is reproducible and less invasive. It has made it possible to delay unfavorable progression and, consequently, hip replacement surgery.展开更多
Background: Knee osteoarthritis is a frequent, debilitating, and degenerative condition. It is the most common operative indication for surgical arthroscopy. Hypothesis: Arthroscopy allows painless treatment of knee o...Background: Knee osteoarthritis is a frequent, debilitating, and degenerative condition. It is the most common operative indication for surgical arthroscopy. Hypothesis: Arthroscopy allows painless treatment of knee osteoarthritis and functional recovery. Patients and Methods: Our study was conducted in a private medical center in the city of Brazzaville in Congo, during the period from September 2020 to February 2023. It was prospective and based on patients with mechanical knee pain caused by osteoarthritis. A mobile arthroscopy device was used. The IKDC and KOOS scores allowed the evaluation of the treatment. Results: Our work involved 15 men and 7 women, with an average age of 39.9 years. Knee osteoarthritis was classified as type 2 according to Ahlbäck in 26 cases (70.27%) and type 3 in 11 cases (29.73%). In 7 patients, arthroscopy revealed lesions not visualized on MRI. Joint lavage was performed in all cases, synovial debridement in 17 cases (45.94%), and extraction of cartilaginous foreign bodies in 10 cases (27.03%). 20 patients were very satisfied with the surgery and 2 moderately satisfied. The EVA, subjective IKDC and KOOS scores were acceptable on a long-term follow-up. Discussion: Arthroscopy is a modern surgical technique for the management of intra-articular lesions of the knee. It relieves pain and stabilizes the degenerative process. A mobile arthroscopy device used here was preferred because of the low cost of installation and production.展开更多
Aim: To evaluate the anesthetic management of neurosurgical patients in University Hospital of Brazzaville. Materials and methods: We performed a transversal and descriptive study during the period from January to Jun...Aim: To evaluate the anesthetic management of neurosurgical patients in University Hospital of Brazzaville. Materials and methods: We performed a transversal and descriptive study during the period from January to June 2015 into operating room of the University Hospital of Brazzaville. 60 cases of anesthesia have been analyzed. Results: The neurosurgery represented 2.88% of the activity of the operating room in University Hospital of Brazzaville. The average age was 44.7 ± 18.36 years old. The sex ratio was 1.07. The scheduled interventions have concerned 83.4% of cases. Surgical indications were concerned the spine degenerative disease and spinal trauma in 40% and 18.3% of cases respectively. The patients classified ASA I and II were most represented in 40% and 46.7% of cases respectively. General anesthesia was used in 98.4% of cases. The peroperative complications were represented by arterial hypotension (31.7%), hemorrhage (11.7%), bradycardia (5%), difficult intubation (3.3%) and one case of peroperative cardiac arrest. The blood transfusion rate was 18.7%. The stay in ICU concerned 8.3% of the cases. We recorded three cases (5%) of death in our series. Conclusion: The neuroanesthesia knows an evolution in our country because of increasing number of neurosurgeons;it’s necessary to train medical staff in her practice.展开更多
<b><span style="font-family:Verdana;">Aim: </span></b><span style="font-family:""><span style="font-family:Verdana;">To determine etiological, the...<b><span style="font-family:Verdana;">Aim: </span></b><span style="font-family:""><span style="font-family:Verdana;">To determine etiological, therapeutic aspects and issues of AGP in intensive care unit (ICU) at University Hospital of Brazzaville (UHB). </span><b><span style="font-family:Verdana;">Materials and Methods: </span></b><span style="font-family:Verdana;">It was a retrospective and descriptive study carried out from January to December 2016 in ICU at UHB. We collected completed medical records of patients admitted and operated for AGP regardless of age or sex. The parameters studied were age, sex, admission’s reasons, etiologies, management, post-operative complications, length of hospital and mortality. Data were treated in Excel 2010 and Epi info 2007. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">Thirty-one complete medical records were identified (mean age: 40.6 ± 22.0 years). The sex ratio was 2.4. Shock was the most common reason for admission with 67.7% of the cases. The etiologies of AGP w</span></span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> dominated by gastroduodenal perforating ulcer (41.9%) followed </span><span style="font-family:Verdana;">by </span><span style="font-family:""><span style="font-family:Verdana;">complicated appendicitis (19.4%). The management of all patients was medico-surgical. The bi antibiotic ceftriaxone-metronidazole was administered in 29 patients (93.6%). 18 patients (59.1%) received vasopressor therapy. The complications had occurred among 9 patients </span><i><span style="font-family:Verdana;">i.e.</span></i><span style="font-family:Verdana;"> 29% of the cases;parietal suppurations represented 44.5% of the complications. The average length of hospitalization was 5.2 ± 4.6 days. The overall mortality was 41.9%. </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">In our study, the most frequent etiologies were gastroduodenal perforating ulcer and complicated appendicitis. They affected young patients. The complications were dominated by parietal suppurations. The mortality rate was high.展开更多
This article analyses the determinants of young women’s participation in the labour market. For this purpose, the Employment Policy Enhancement Survey (EAPE), conducted by the Laboratoire de Recherches et d’Etudes E...This article analyses the determinants of young women’s participation in the labour market. For this purpose, the Employment Policy Enhancement Survey (EAPE), conducted by the Laboratoire de Recherches et d’Etudes Economiques et Sociales (LARES) in collaboration with CERDI in 2018 was used as the database. The results of Gallant and Nychka’s (1987) semi-nonparametric procedure show that health status, household size, marital status, and educational attainment are explanatory factors of young women’s labour market participation in Congo.展开更多
The soil seed bank is an important source of restoration and resilience of disturbed ecosystems. This study evaluates the regeneration potential through the soil seed bank of the shrub savannas of Nguela and Mbe in or...The soil seed bank is an important source of restoration and resilience of disturbed ecosystems. This study evaluates the regeneration potential through the soil seed bank of the shrub savannas of Nguela and Mbe in order to predict the eventual dynamics. Three plots of 0.25 ha subdivided into four sub-plots of 0.015 ha have been installed in each savannah. In total, 48 samples of each savannah, i.e. 96 samples of both savannas, have been taken from the soil layers, 0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm. Species diversity and abundance of the soil seed bank have been assessed after germination. The results reveal 167 seedlings belonging to 23 species in the Mbe savannah and 144 seedlings belonging to 14 species in the Nguela savannah. The total densities of the germinated seeds were respectively 463.63 seeds/m<sup>2</sup> and 400 seeds/m<sup>2</sup>. Nevertheless, the 20 cm deep layers have illustrated themselves compared to the superficial layers with densities of 16.29 seeds/m<sup>2</sup> and 21.66 seeds/m<sup>2</sup>, respectively, in the savannas of Mbe and Nguela. Herbaceous species largely dominated, with percentages of 91% and 100%, respectively, in the savannas of Mbe and Nguela. Alone, the Trema orientalis (L.) Blume species has been identified as woody species in the Mbe savannah. The greatest specific richness has been obtained in the first five centimeters of soil, with 21.73% and 28.57% of exclusive species, respectively, in the savannas of Mbe and Nguela. The results reveal that restoration through the soil seed bank would be limited to a single woody species found (T. orientalis). Consequently, the study suggests silvicultural interventions based on planting or enrichment techniques for sustainably managed savannas exposed to anthropogenic disturbances.展开更多
The soil seed bank is a key indicator of natural regeneration and/or forests resilience after disturbances. This study evaluates the soil seed bank characteristics in two Marantaceae forests plots of Ouesso Forest Ind...The soil seed bank is a key indicator of natural regeneration and/or forests resilience after disturbances. This study evaluates the soil seed bank characteristics in two Marantaceae forests plots of Ouesso Forest Industry (IFO) in north of the Republic of Congo. In each plot, 12 samples were taken per soil layers (0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm deep). Diversity and abundance seed were estimated after germination of soil samples. The results revealed 101 seedlings belonging to 17 species for plot 1 and 129 seedlings belonging to 15 species for plot 2. The average densities of germinated seeds were respectively 281 seedling/m<sup>2</sup> and 358 seedling/m<sup>2</sup>. There were no significant differences (p > 0.05) between the mean densities of the two plots. Herbaceous species dominated with percentages of 71% and 73%, respectively in plot 1 and plot 2. Both plots showed potential of regeneration from the soil seed bank. However, this potential seems higher in plot 2. Pioneer taxa were more abundant in the soil seed bank of plot 1 (4 woody pioneer species) than in plot 2 (1 woody pioneer species). The highest species richness was obtained in the first two soil layers (0 - 5 cm and 5 - 10 cm depth) while 25% of species were exclusively found in the deepest layer (15 - 20 cm) in plot 2. The study suggests silvicultural interventions based on planting or enrichment techniques for contribute to sustainable management of Marantaceae forests that could prevent the growth and development of seedlings.展开更多
The soil seed bank is considered as an important mechanism for the natural regeneration, resilience and conservation of the forests after disturbances. This study evaluates the characteristics of the soil seed bank in...The soil seed bank is considered as an important mechanism for the natural regeneration, resilience and conservation of the forests after disturbances. This study evaluates the characteristics of the soil seed bank in two post-logging plots of Loundoungou-Toukoulaka Forest Management Unit: one plot exploited in 2008 and another exploited in 2021. In each study plot, 40 samples were collected per soil layer (0 - 5 cm, 5 - 10 cm, 10 - 15 cm, 15 - 20 cm and 20 - 25 cm depth). The species diversity and abundance of the soil seed bank were estimated after soil samples were brought to germination. The results demonstrated that 347 seedlings belonging to 37 species in the plot exploited in 2008 and 418 seedlings belonging to 27 species in that exploited in 2021 germinated during 20 weeks of monitoring. The total densities of the seedlings identified were respectively 1446 seedlings/m<sup>2</sup> and 1742 seedlings/m<sup>2</sup>. The plot exploited in 2021 presented a higher proportion of herbaceous species (93.78%) compared to that exploited in 2008 (82.71%). Two pioneer species were recorded in the plot exploited in 2008. These are Macaranga barteri (0.29%) in the 0 - 5 cm layer and Musanga cecropioides (2.31%) up to 20 cm deep. On the other hand, in the plot exploited in 2021, Macaranga spinosa (0.96%) in the 0 - 5 cm layer and M. cecropioides (0.96%) up to 20 cm deep were identified. In the plot exploited in 2008, the 20 - 25 cm layer demonstrated important proportions in woody species (9%), these are in particular Rubiaceae sp.4 and Nauclea diderrichii. While that exploited in 2021, presented 19% of woody species, namely the species of Rubiaceae sp.4, Rubiaceae sp.5 and N. diderrichii, greatly exceeding the proportions obtained in the 15 - 20 cm layer of the two plots. Nonetheless, N. diderrichii was the only commercial species recorded with densities of 108 seedlings/m<sup>2</sup> and 4 seedlings/m<sup>2</sup>, respectively in the plot exploited in 2008 and that exploited in 2021. Commercial tree species are poorly represented in the soil seed bank. Consequently, the study suggests that to improve the natural regeneration of the commercial species, silvicultural interventions based on planting techniques in the exploited plots should be more effective in order to sustainably manage these production forests.展开更多
Natural regeneration is the basis of a dynamic and demographic balance of plant populations. The objective of this study was to assess the natural regeneration potential of woody species along secondary roads post-log...Natural regeneration is the basis of a dynamic and demographic balance of plant populations. The objective of this study was to assess the natural regeneration potential of woody species along secondary roads post-logging abandoned since 2008 and 2018. In the two Annual Allowable Cuts (AAC 2008 and AAC 2018), 24 regenerating sub-plots (i.e. 12 sub-plots for AAC 2008 and 12 sub-plots for AAC 2018) with a unit area of 5 m × 5 m were delimited with a total area of 0.06 ha (i.e. 0.03 ha for each AAC). The abundance and diversity of woody species were respectively inventoried and estimated. Two estimators of the specific richness were used to estimate the floristic diversity of each Annual Allowable Cuts (AAC). The results reveal globally 88 woody species in the AAC 2008 and 241 woody species in the AAC 2018, with respective average densities of 2933 stem/ha and 8033 stem/ha. There was a very highly significant difference between the mean densities of the two AAC (Kruskal-Wallis test;H = 2.36, p-value < 0.000). The results also highlight a great diversity and a relatively high abundance of woody species in the 2018 AAC compared to the 2008 AAC. Also, the spatial structuring of the sub-plots on the basis of Principal Component Analysis (PCA) demonstrates that the floristic composition of the two AAC is globally different. The study suggests silvicultural interventions and the long-term assessment of regenerating woody species along abandoned secondary roads in order to guarantee the sustainable management of their population.展开更多
Objective: To determine the role of CD4+ and CD8+ T lymphocytes in the onset of stroke in people living with HIV. Methodology: This was a descriptive, cross-sectional study from January to July 2019, in the neurology ...Objective: To determine the role of CD4+ and CD8+ T lymphocytes in the onset of stroke in people living with HIV. Methodology: This was a descriptive, cross-sectional study from January to July 2019, in the neurology department of loandjili general hospital, including any patient hospitalized for a first episode of stroke confirmed by brain scan. The study variables were: age, sex, CRP value, serum T cell CD4+, CD8+. The statistical analysis was carried out using the EPI info 7 software. Results: Twenty stroke patients were included. The relative frequency of HIV was 20%. The risk factors were potentiated by immunosuppression of CD4+ T cells. Sixty percent (60%) of the patients had a CD4+ count < 200/mm<sup>3</sup> and the mean CD4+ count was ±191/mm<sup>3</sup>. Stroke was the predominant mechanism of injury with a frequency of 70%, the only injury mechanism of stroke in patients with CD8+ T cell count > 800/mm<sup>3</sup> (p = 0.04). Conclusion: Risk factors are potentiated by TCD4+ lymphocyte immunosupression, also CD8+ lymphocytes of immune system activation marker are a cardiovascular risk factor for living people with HIV.展开更多
<strong>Introduction:</strong> The role of immunosuppression of TCD4<sup>+</sup> lymphocytes in the onset of stroke in people living with HIV has been reported in numerous studies examining the...<strong>Introduction:</strong> The role of immunosuppression of TCD4<sup>+</sup> lymphocytes in the onset of stroke in people living with HIV has been reported in numerous studies examining the co-morbidity of stroke and HIV. Objective: To determine the correlation between the viral load and the type of stroke. <strong>Methodology:</strong> This was a 7-month cross-sectional descriptive study carried out in the Neurology Department of Loandjili General Hospital in Pointe-Noire. The study population consisted of patients living with HIV who had a stroke confirmed by brain scan. The sero-immunological investigation consisted of looking for T lymphocyte typing from two kits: a CD4<sup>+</sup> T lymphocyte typing reagent kit (BD FACS Presto TM) and a GeneXpert kit for viral load (Xpert<sup><span style="color:#000000;font-family:Roboto, "white-space:normal;background-color:#D46399;">®</span></sup>HIV-1 Viral Load). The database was made from the 2010 version of Microsoft Excel. <strong>Results:</strong> We included 16 patients living with HIV, 56% of whom were women with a sex ration of 0.78. The mean age was 56.92 ± 11.21. The mean number of TCD4<sup>+</sup> lymphocytes was 413.44 ± 677.95/mm<sup>3</sup>;minimum: 93/mm<sup>3</sup>;maximum: 2854/mm<sup>3</sup>. The mean viral load was 17,996.31 ± 20,982.22/mm<sup>3</sup>;minimum: 1002/mm<sup>3</sup>;maximum: 67,229/mm<sup>3</sup>. No significant difference between the viral load and the occurrence of the stroke (p = 0.13). <strong>Conclusion:</strong> Our study did not show a causal link between viral load, immunosuppression of TCD4<sup>+</sup> lymphocytes and the onset of stroke.展开更多
文摘Introduction: Osteonecrosis of the femoral head (ONTF) is a debilitating condition. Several treatments have been proposed with controversial results. The aim of our study was to evaluate treatment by surgical drilling coupled with in situ cancellous grafting. Materials and methods: Our study was a case-control study conducted at Brazzaville University Hospital from 1st January 2018 to 31 December 2023. It compared two groups of patients with ONTF: non-operated (13 patients, 20 hips) and operated (22 patients, 35 hips). We used the visual digital scale (VDS) for pain assessment, the Merle D’Aubigne-Postel (MDP) scoring system for clinical and functional assessment, and the evolution of necrosis. Results: The group of non-operated patients had a mean age of 35.69 ± 3.4 years, no improvement in pain with an EVN above seven at the last recoil and a mean global MDP score falling from 12.7 before offloading to 10.13 at one year. The group of patients operated on had a mean age of 37.86 ± 7.02 years, a significant reduction in pain (p = 0.00004) and a significantly increased MDP score (p = 0.0034). A comparison of the two groups of patients showed significant stabilization of the necrotic lesions in the operated patients (p = 0.00067), with better satisfaction in the same group. Conclusion: Surgical drilling combined with grafting in the treatment of early-stage ONTF has improved progress in our series. The technique is reproducible and less invasive. It has made it possible to delay unfavorable progression and, consequently, hip replacement surgery.
文摘Background: Knee osteoarthritis is a frequent, debilitating, and degenerative condition. It is the most common operative indication for surgical arthroscopy. Hypothesis: Arthroscopy allows painless treatment of knee osteoarthritis and functional recovery. Patients and Methods: Our study was conducted in a private medical center in the city of Brazzaville in Congo, during the period from September 2020 to February 2023. It was prospective and based on patients with mechanical knee pain caused by osteoarthritis. A mobile arthroscopy device was used. The IKDC and KOOS scores allowed the evaluation of the treatment. Results: Our work involved 15 men and 7 women, with an average age of 39.9 years. Knee osteoarthritis was classified as type 2 according to Ahlbäck in 26 cases (70.27%) and type 3 in 11 cases (29.73%). In 7 patients, arthroscopy revealed lesions not visualized on MRI. Joint lavage was performed in all cases, synovial debridement in 17 cases (45.94%), and extraction of cartilaginous foreign bodies in 10 cases (27.03%). 20 patients were very satisfied with the surgery and 2 moderately satisfied. The EVA, subjective IKDC and KOOS scores were acceptable on a long-term follow-up. Discussion: Arthroscopy is a modern surgical technique for the management of intra-articular lesions of the knee. It relieves pain and stabilizes the degenerative process. A mobile arthroscopy device used here was preferred because of the low cost of installation and production.
文摘Aim: To evaluate the anesthetic management of neurosurgical patients in University Hospital of Brazzaville. Materials and methods: We performed a transversal and descriptive study during the period from January to June 2015 into operating room of the University Hospital of Brazzaville. 60 cases of anesthesia have been analyzed. Results: The neurosurgery represented 2.88% of the activity of the operating room in University Hospital of Brazzaville. The average age was 44.7 ± 18.36 years old. The sex ratio was 1.07. The scheduled interventions have concerned 83.4% of cases. Surgical indications were concerned the spine degenerative disease and spinal trauma in 40% and 18.3% of cases respectively. The patients classified ASA I and II were most represented in 40% and 46.7% of cases respectively. General anesthesia was used in 98.4% of cases. The peroperative complications were represented by arterial hypotension (31.7%), hemorrhage (11.7%), bradycardia (5%), difficult intubation (3.3%) and one case of peroperative cardiac arrest. The blood transfusion rate was 18.7%. The stay in ICU concerned 8.3% of the cases. We recorded three cases (5%) of death in our series. Conclusion: The neuroanesthesia knows an evolution in our country because of increasing number of neurosurgeons;it’s necessary to train medical staff in her practice.
文摘<b><span style="font-family:Verdana;">Aim: </span></b><span style="font-family:""><span style="font-family:Verdana;">To determine etiological, therapeutic aspects and issues of AGP in intensive care unit (ICU) at University Hospital of Brazzaville (UHB). </span><b><span style="font-family:Verdana;">Materials and Methods: </span></b><span style="font-family:Verdana;">It was a retrospective and descriptive study carried out from January to December 2016 in ICU at UHB. We collected completed medical records of patients admitted and operated for AGP regardless of age or sex. The parameters studied were age, sex, admission’s reasons, etiologies, management, post-operative complications, length of hospital and mortality. Data were treated in Excel 2010 and Epi info 2007. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">Thirty-one complete medical records were identified (mean age: 40.6 ± 22.0 years). The sex ratio was 2.4. Shock was the most common reason for admission with 67.7% of the cases. The etiologies of AGP w</span></span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> dominated by gastroduodenal perforating ulcer (41.9%) followed </span><span style="font-family:Verdana;">by </span><span style="font-family:""><span style="font-family:Verdana;">complicated appendicitis (19.4%). The management of all patients was medico-surgical. The bi antibiotic ceftriaxone-metronidazole was administered in 29 patients (93.6%). 18 patients (59.1%) received vasopressor therapy. The complications had occurred among 9 patients </span><i><span style="font-family:Verdana;">i.e.</span></i><span style="font-family:Verdana;"> 29% of the cases;parietal suppurations represented 44.5% of the complications. The average length of hospitalization was 5.2 ± 4.6 days. The overall mortality was 41.9%. </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">In our study, the most frequent etiologies were gastroduodenal perforating ulcer and complicated appendicitis. They affected young patients. The complications were dominated by parietal suppurations. The mortality rate was high.
文摘This article analyses the determinants of young women’s participation in the labour market. For this purpose, the Employment Policy Enhancement Survey (EAPE), conducted by the Laboratoire de Recherches et d’Etudes Economiques et Sociales (LARES) in collaboration with CERDI in 2018 was used as the database. The results of Gallant and Nychka’s (1987) semi-nonparametric procedure show that health status, household size, marital status, and educational attainment are explanatory factors of young women’s labour market participation in Congo.
文摘The soil seed bank is an important source of restoration and resilience of disturbed ecosystems. This study evaluates the regeneration potential through the soil seed bank of the shrub savannas of Nguela and Mbe in order to predict the eventual dynamics. Three plots of 0.25 ha subdivided into four sub-plots of 0.015 ha have been installed in each savannah. In total, 48 samples of each savannah, i.e. 96 samples of both savannas, have been taken from the soil layers, 0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm. Species diversity and abundance of the soil seed bank have been assessed after germination. The results reveal 167 seedlings belonging to 23 species in the Mbe savannah and 144 seedlings belonging to 14 species in the Nguela savannah. The total densities of the germinated seeds were respectively 463.63 seeds/m<sup>2</sup> and 400 seeds/m<sup>2</sup>. Nevertheless, the 20 cm deep layers have illustrated themselves compared to the superficial layers with densities of 16.29 seeds/m<sup>2</sup> and 21.66 seeds/m<sup>2</sup>, respectively, in the savannas of Mbe and Nguela. Herbaceous species largely dominated, with percentages of 91% and 100%, respectively, in the savannas of Mbe and Nguela. Alone, the Trema orientalis (L.) Blume species has been identified as woody species in the Mbe savannah. The greatest specific richness has been obtained in the first five centimeters of soil, with 21.73% and 28.57% of exclusive species, respectively, in the savannas of Mbe and Nguela. The results reveal that restoration through the soil seed bank would be limited to a single woody species found (T. orientalis). Consequently, the study suggests silvicultural interventions based on planting or enrichment techniques for sustainably managed savannas exposed to anthropogenic disturbances.
文摘The soil seed bank is a key indicator of natural regeneration and/or forests resilience after disturbances. This study evaluates the soil seed bank characteristics in two Marantaceae forests plots of Ouesso Forest Industry (IFO) in north of the Republic of Congo. In each plot, 12 samples were taken per soil layers (0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm deep). Diversity and abundance seed were estimated after germination of soil samples. The results revealed 101 seedlings belonging to 17 species for plot 1 and 129 seedlings belonging to 15 species for plot 2. The average densities of germinated seeds were respectively 281 seedling/m<sup>2</sup> and 358 seedling/m<sup>2</sup>. There were no significant differences (p > 0.05) between the mean densities of the two plots. Herbaceous species dominated with percentages of 71% and 73%, respectively in plot 1 and plot 2. Both plots showed potential of regeneration from the soil seed bank. However, this potential seems higher in plot 2. Pioneer taxa were more abundant in the soil seed bank of plot 1 (4 woody pioneer species) than in plot 2 (1 woody pioneer species). The highest species richness was obtained in the first two soil layers (0 - 5 cm and 5 - 10 cm depth) while 25% of species were exclusively found in the deepest layer (15 - 20 cm) in plot 2. The study suggests silvicultural interventions based on planting or enrichment techniques for contribute to sustainable management of Marantaceae forests that could prevent the growth and development of seedlings.
文摘The soil seed bank is considered as an important mechanism for the natural regeneration, resilience and conservation of the forests after disturbances. This study evaluates the characteristics of the soil seed bank in two post-logging plots of Loundoungou-Toukoulaka Forest Management Unit: one plot exploited in 2008 and another exploited in 2021. In each study plot, 40 samples were collected per soil layer (0 - 5 cm, 5 - 10 cm, 10 - 15 cm, 15 - 20 cm and 20 - 25 cm depth). The species diversity and abundance of the soil seed bank were estimated after soil samples were brought to germination. The results demonstrated that 347 seedlings belonging to 37 species in the plot exploited in 2008 and 418 seedlings belonging to 27 species in that exploited in 2021 germinated during 20 weeks of monitoring. The total densities of the seedlings identified were respectively 1446 seedlings/m<sup>2</sup> and 1742 seedlings/m<sup>2</sup>. The plot exploited in 2021 presented a higher proportion of herbaceous species (93.78%) compared to that exploited in 2008 (82.71%). Two pioneer species were recorded in the plot exploited in 2008. These are Macaranga barteri (0.29%) in the 0 - 5 cm layer and Musanga cecropioides (2.31%) up to 20 cm deep. On the other hand, in the plot exploited in 2021, Macaranga spinosa (0.96%) in the 0 - 5 cm layer and M. cecropioides (0.96%) up to 20 cm deep were identified. In the plot exploited in 2008, the 20 - 25 cm layer demonstrated important proportions in woody species (9%), these are in particular Rubiaceae sp.4 and Nauclea diderrichii. While that exploited in 2021, presented 19% of woody species, namely the species of Rubiaceae sp.4, Rubiaceae sp.5 and N. diderrichii, greatly exceeding the proportions obtained in the 15 - 20 cm layer of the two plots. Nonetheless, N. diderrichii was the only commercial species recorded with densities of 108 seedlings/m<sup>2</sup> and 4 seedlings/m<sup>2</sup>, respectively in the plot exploited in 2008 and that exploited in 2021. Commercial tree species are poorly represented in the soil seed bank. Consequently, the study suggests that to improve the natural regeneration of the commercial species, silvicultural interventions based on planting techniques in the exploited plots should be more effective in order to sustainably manage these production forests.
文摘Natural regeneration is the basis of a dynamic and demographic balance of plant populations. The objective of this study was to assess the natural regeneration potential of woody species along secondary roads post-logging abandoned since 2008 and 2018. In the two Annual Allowable Cuts (AAC 2008 and AAC 2018), 24 regenerating sub-plots (i.e. 12 sub-plots for AAC 2008 and 12 sub-plots for AAC 2018) with a unit area of 5 m × 5 m were delimited with a total area of 0.06 ha (i.e. 0.03 ha for each AAC). The abundance and diversity of woody species were respectively inventoried and estimated. Two estimators of the specific richness were used to estimate the floristic diversity of each Annual Allowable Cuts (AAC). The results reveal globally 88 woody species in the AAC 2008 and 241 woody species in the AAC 2018, with respective average densities of 2933 stem/ha and 8033 stem/ha. There was a very highly significant difference between the mean densities of the two AAC (Kruskal-Wallis test;H = 2.36, p-value < 0.000). The results also highlight a great diversity and a relatively high abundance of woody species in the 2018 AAC compared to the 2008 AAC. Also, the spatial structuring of the sub-plots on the basis of Principal Component Analysis (PCA) demonstrates that the floristic composition of the two AAC is globally different. The study suggests silvicultural interventions and the long-term assessment of regenerating woody species along abandoned secondary roads in order to guarantee the sustainable management of their population.
文摘Objective: To determine the role of CD4+ and CD8+ T lymphocytes in the onset of stroke in people living with HIV. Methodology: This was a descriptive, cross-sectional study from January to July 2019, in the neurology department of loandjili general hospital, including any patient hospitalized for a first episode of stroke confirmed by brain scan. The study variables were: age, sex, CRP value, serum T cell CD4+, CD8+. The statistical analysis was carried out using the EPI info 7 software. Results: Twenty stroke patients were included. The relative frequency of HIV was 20%. The risk factors were potentiated by immunosuppression of CD4+ T cells. Sixty percent (60%) of the patients had a CD4+ count < 200/mm<sup>3</sup> and the mean CD4+ count was ±191/mm<sup>3</sup>. Stroke was the predominant mechanism of injury with a frequency of 70%, the only injury mechanism of stroke in patients with CD8+ T cell count > 800/mm<sup>3</sup> (p = 0.04). Conclusion: Risk factors are potentiated by TCD4+ lymphocyte immunosupression, also CD8+ lymphocytes of immune system activation marker are a cardiovascular risk factor for living people with HIV.
文摘<strong>Introduction:</strong> The role of immunosuppression of TCD4<sup>+</sup> lymphocytes in the onset of stroke in people living with HIV has been reported in numerous studies examining the co-morbidity of stroke and HIV. Objective: To determine the correlation between the viral load and the type of stroke. <strong>Methodology:</strong> This was a 7-month cross-sectional descriptive study carried out in the Neurology Department of Loandjili General Hospital in Pointe-Noire. The study population consisted of patients living with HIV who had a stroke confirmed by brain scan. The sero-immunological investigation consisted of looking for T lymphocyte typing from two kits: a CD4<sup>+</sup> T lymphocyte typing reagent kit (BD FACS Presto TM) and a GeneXpert kit for viral load (Xpert<sup><span style="color:#000000;font-family:Roboto, "white-space:normal;background-color:#D46399;">®</span></sup>HIV-1 Viral Load). The database was made from the 2010 version of Microsoft Excel. <strong>Results:</strong> We included 16 patients living with HIV, 56% of whom were women with a sex ration of 0.78. The mean age was 56.92 ± 11.21. The mean number of TCD4<sup>+</sup> lymphocytes was 413.44 ± 677.95/mm<sup>3</sup>;minimum: 93/mm<sup>3</sup>;maximum: 2854/mm<sup>3</sup>. The mean viral load was 17,996.31 ± 20,982.22/mm<sup>3</sup>;minimum: 1002/mm<sup>3</sup>;maximum: 67,229/mm<sup>3</sup>. No significant difference between the viral load and the occurrence of the stroke (p = 0.13). <strong>Conclusion:</strong> Our study did not show a causal link between viral load, immunosuppression of TCD4<sup>+</sup> lymphocytes and the onset of stroke.