Normal values and regional differences in oesophageal impedance-pH metrics: a consensus analysis of impedance-pH studies from around the world.

OBJECTIVE: Limitations of existing impedance-pH thresholds include small sample size of normative studies, inclusion of artefactual pH drops and incorrect identification of impedance reflux events. We aimed to obtain new impedance-pH thresholds from expert consensus analysis of tracings from a large number of healthy subjects. DESIGN: Of 541 studies performed worldwide using two different systems (Diversatek, USA, and Laborie, Netherlands), 150 tracings with oesophageal diagnoses, behavioural disorders and study-related artefacts were excluded. The remainder studies were subject to two reviewer consensus analysis, in-person or through video conference, consisting of editing meals and pH drops, identification of impedance reflux and postreflux swallow-induced peristaltic wave (PSPW) using strict pre-established criteria and measurement of distal mean nocturnal baseline impedance (MNBI). RESULTS: Consensus analysis was performed in 391 tracings (age 32.7 years, range 18-71, 54.2% female). Normative thresholds were significantly different between Diversatek and Laborie (total acid exposure time: 2.8% and 5%; reflux episodes: 55 and 78; MNBI at 3 cm: 1400 and 1500 ohms, at 5 cm: 1400 and 1800 ohms). Males had higher acid exposure, more reflux episodes and lower MNBI. Significant regional differences were identified, including higher PSPW scores in Western countries, and higher MNBI in Asia using Diversatek, and higher acid exposure in the Netherlands, higher MNBI in Asia and South Africa, and lower MNBI in Turkey using Laborie. CONCLUSION: Normal impedance-pH monitoring thresholds have regional and system-related differences. Clinical interpretation needs to use normal thresholds valid for the system used and world region, following careful editing of the tracings.

Uncovering Risks Associated with Smoking Types and Intensities in Esophageal Cancer within High-Prevalence Regions in Africa: A Comprehensive Meta-analysis.

Tobacco is usually cited among the well-known risk factors of esophageal cancer; nevertheless, the extent of the contribution of the type of smoking and its intensity to the disease has not been comprehensively elucidated in Africa. We searched MEDLINE/PubMed, Excerpta Medica Database, Web of Science, Scopus, Cochrane Library, and African Journals Online studies published before September 2023. The quality of the studies was assessed using the Newcastle-Ottawa scale, and the funnel plot was used for assessing potential publication bias. Meta-analyses were conducted to estimate summary effects using random-effects models. This study included 22,319 participants from 27 studies. The results strongly indicate a significant association between tobacco use and a higher risk of esophageal cancer. The risk of esophageal cancer is notably higher among pipe smokers [OR = 4.68; 95% confidence interval (CI), 3.38-6.48], followed by hand-rolled cigarette smokers (OR = 3.79; 95% CI, 2.68-5.35), in comparison with those who smoked commercially manufactured cigarettes (OR = 2.46; 95% CI, 1.69-3.60). Our findings also showed that the risk of esophageal cancer is highest in people smoking >183 packs per year (OR = 5.47; 95% CI, 3.93-7.62), followed by those smoking 93 to 183 packs per year (OR = 3.90; 95% CI, 3.13-4.86), in comparison with those smoking ≤92 packs per year (OR = 2.90; 95% CI, 2.19-3.84). Our findings strongly show that among the different types of tobacco use in Africa, pipe and hand-roller smokers face a higher risk of esophageal cancer.

HIV infection and esophageal cancer in Sub-Saharan Africa: a comprehensive meta-analysis.

Africa hosts the highest burden of esophageal cancer (49%) and HIV (60%) worldwide. It is imperative to investigate the synergistic impact of these two diseases on African populations. This study conducted an exhaustive computerized search of databases, including Medline/PubMed, Embase, Web of Science, Scopus, Cochrane library, and African Journals Online, to identify eligible studies up to October 2023. HIV infection was the exposure, esophageal cancer risk was the outcome, and healthy subjects with no cancer history served as comparators. Study quality was assessed using the Newcastle-Ottawa scale, and potential publication bias was evaluated through funnel plots and the Egger test. Meta-analyses were conducted using Stata 17.0 software and involved a thorough examination of 98,397 studies. Out of these, eight studies originating from Eastern and Southern Africa, recognized as esophageal cancer hotspots on the continent, met the eligibility criteria. The analysis revealed a non-significant association between HIV infection and esophageal cancer risk (odds ratio = 1.34 [95% confidence interval, 0.85-2.12]; with 0.26 as p-value of overall effects). The Egger test yielded a p-value of 0.2413, suggesting the absence of publication bias. In summary, this systematic review and meta-analysis indicate that there is no established causal link between HIV infection and esophageal cancer risk. However, further research is essential to delve into the potential mechanisms underlying this relationship.

Drinking patterns, alcoholic beverage types, and esophageal cancer risk in Africa: a comprehensive systematic review and meta-analysis.

Africa is the continent most affected by esophageal cancer in the world. Alcoholic beverages are controversially blamed, as esophageal cancer is a rare disease in several other countries ranked in the top 10 for consumption of alcoholic beverages. This study aims to conduct a comprehensive systematic review of published literature, statistically summarizing the strength of the association between drinking patterns and types, and the risk of esophageal cancer in Africa. A computerized search of reputable databases such as Medline/PubMed, EMBASE, Web of Science, and African Journals Online was performed to identify relevant studies published up to September 2023. The quality of the studies was evaluated using the Newcastle-Ottawa scale for case-control studies and the Agency for Healthcare Research and Quality tool for cross-sectional studies. A funnel plot and Egger test were utilized to assess potential publication bias. Meta-analyses were conducted using random-effects models with RevMan 5.3 and Stata software to estimate summary effects. The systematic review identified a total of 758,203 studies, primarily from Eastern and Southern Africa. The pooled samples across all studies comprised 29,026 individuals, including 11,237 individuals with cancer and 17,789 individuals without cancer. Meta-analysis revealed a significant association between alcohol consumption and the risk of esophageal cancer (odds ratio [OR] = 1.81; 95% confidence interval [CI], 1.50-2.19). Further analysis based on the frequency of alcoholic beverage consumption indicated a stronger association with daily (OR = 2.38; 95% CI, 1.81-3.13) and weekly (OR = 1.94; 95% CI, 1.32-2.84) drinkers in contrast to occasional drinkers (OR = 1.02; 95% CI, 0.81-1.29). Additionally, consumption of traditional alcoholic beverages was significantly associated with the risk of esophageal cancer in African populations (OR = 2.00; 95% CI, 1.42-2.82). However, no relationship has been established between the exclusive consumption of non-traditional drinks and the risk of esophageal cancer. In conclusion, the results of this study confirm the hypothesis that daily and weekly drinking patterns, significantly increase the risk of esophageal cancer in Africa, while occasional consumption does not show a significant association. Additionally, the consumption of traditional alcoholic beverages is notably linked to the risk of esophageal cancer in African populations.

Exploring the use of p53 protein expression as an indicator of oesophageal cancer severity from a high incidence rural area of Africa.

Background: The expression of p53 has been associated with the severity of other types of cancer. There is scanty information when it comes to oesophageal cancer. Objective: This study aimed to explore the use of p53 protein expression as an indicator of oesophageal cancer severity from a high-risk incidence in the African rural population. Methods: Fifty-one patients newly diagnosed with oesophageal cancer were recruited from the endoscopic unit at Nelson Mandela Academic Hospital in Mthatha, South Africa. The serological expression of p53 was measured using the ELISA method and the severity of oesophageal cancer expressed in grade was obtained from the histopathology report from patient's oesophageal biopsies. Results: We found that the expression of p53 was equally distributed among the histological grades of cancer with the value of 2495 pg/mL ± 1736 pg/ mL for lower grades and 2520 ± 1539 pg/mL for higher grades. Furthermore, we found that the level of p53 expression was equally distributed in patients from grade 1, 2, 3, and 4. Conclusion: The expression of p53 protein does not vary according to the histological grade of oesophageal cancer in the given population, therefore may not be helpful as a prognostic factor.

Exploring the use of p53 protein expression as an indicator of oesophageal cancer severity from a high incidence rural area of Africa.

Background: The expression of p53 has been associated with the severity of other types of cancer. There is scanty information when it comes to oesophageal cancer. Objective: This study aimed to explore the use of p53 protein expression as an indicator of oesophageal cancer severity from a high-risk incidence in the African rural population. Methods: Fifty-one patients newly diagnosed with oesophageal cancer were recruited from the endoscopic unit at Nelson Mandela Academic Hospital in Mthatha, South Africa. The serological expression of p53 was measured using the ELISA method and the severity of oesophageal cancer expressed in grade was obtained from the histopathology report from patient's oesophageal biopsies. Results: We found that the expression of p53 was equally distributed among the histological grades of cancer with the value of 2495 pg/mL ± 1736 pg/ mL for lower grades and 2520 ± 1539 pg/mL for higher grades. Furthermore, we found that the level of p53 expression was equally distributed in patients from grade 1, 2, 3, and 4. Conclusion: The expression of p53 protein does not vary according to the histological grade of oesophageal cancer in the given population, therefore may not be helpful as a prognostic factor.

Assessment of Vulnerability to the Covid-19 Pandemic in the Central African Sub-region.

OBJECTIVE: This study was aimed at examining the vulnerability of Central Africa to the COVID-19 pandemic. METHODS: Demographic, health, and socio-economic indicators were used to describe the vulnerability. The study period was from December 31st, 2019 to May 31st, 2020 (i.e. 5 months after the start of the pandemic). RESULTS: According to demographic indicators, African populations appear younger than in Europe, Asia, and North America, where evidence showed a higher lethality of COVID-19 and a higher frequency of hospitalization among the elderly. This highlights the protective effect of the age structure of Central African populations. Their populations face significant vulnerability from high morbidity and a considerable deficit in health care facilities and services. Poverty indicators are not in their favour for a sustainable implementation of effective pandemic control measures. Very low literacy rates in some countries, misinformation, and belief in conspiracy theories could affect the community involvement in the response. Several countries are weakened by other humanitarian crises, including conflicts and other epidemics. The early easing of lockdown restrictions in certain countries could worsen the situation. CONCLUSION: In this sub-region, where the largest proportion of the population lives in poverty, poor sanitary conditions, conflicts, and humanitarian crises, the question of standards of prevention could appear to be a luxurious idea relegated to the background. Central African countries need financial and logistical support for a sustainable and effective response. These observations could be easily extrapolated to other sub-Saharan sub-regions.

The protective effect of aqueous extract of Typha capensis rhizomes on cadmium-induced infertility in rats.

Background Typha capensis is one of the medicinal plants commonly used to manage male fertility problems. The objective of the present study was to assess its fertility-promoting effects in a rat model of cadmium-induced infertility. Methods A total of 30 male Wister rats were randomly divided into five groups of six animals each. Animals of group I, which served as control, were administered with cadmium chloride (CdCl2; 2.5 mg/kg) and normal saline (2 mL/kg). Group II was served with 0.5 mL normal saline only. Animals of groups III-V were treated with CdCl2 (2.5 mg/kg) plus T. capensis extract at doses of 100, 200, and 400 mg/kg, respectively. Animals were sacrificed under sedation. Testes and epididymal weights and sperm count were determined. Histological assessment of the testes was conducted. Results T. capensis at any dose did not improve (p > 0.05) testicular and epididymal weights compared with those of the CdCl2-exposed control group. Histology revealed moderate necrosis in the same group. T. capensis modestly increased the sperm count by 14%, 31%, and 35%, for groups treated with the extract at doses 100, 200, and 400 mg/kg, respectively, when compared with the CdCl2 control group, although the differences were not significant statistically (p > 0.05). Conclusions Results of our study demonstrated that T. capensis can neither offer protective effects against oxidative stress nor promote fertility in an animal model of cadmium-induced infertility.

24-Hour Measurement of Gastric pH in Rural South Africa.

Background. Previous studies have established norms of 24-hour gastric pH profiles for western countries. This study was designed to establish the pattern for a rural African population with a high incidence of oesophageal cancer. Methods. After lower oesophageal manometry a probe was placed 10 cm distal to the lower oesophageal sphincter. We carried out 24-hour ambulatory monitoring of gastric pH on 59 healthy subjects. This was satisfactorily completed on 26 female and 18 male (age 21-64, median 35) subjects in the Transkei region of South Africa. Results. The mean 24 hour gastric pH was 2.84 and the mean night-time pH was 3.7. 40 volunteers recorded a night-time pH reaching over 4. 33 volunteers recorded a night-time pH over 7. Night-time alkalinisation was present for 136.4 minutes (25th centile 22.8, 75th centile 208.1) at pH4 or over, and 79.3 (2.5, 122.7) minutes at pH7 or over. Episodes of rapid alkaline rise were 17 (10, 47). 21.1% of these occurred while supine. 35 of 36 tested subjects were positive for H. pylori IgG. Conclusion. Gastric alkalinisation is common in Transkei, at a higher pH than that reported in other studies, and is sustained longer. Nighttime alkalinisation is frequent. This suggests a high level of duodenogastric reflux.

Anti-inflammatory and membrane-stabilizing properties of two semisynthetic derivatives of oleanolic acid.

Acetylation and methylation semisynthesis of oleanolic acid (OA) isolated from Syzygium aromaticum L. yielded two compounds: 3-acetoxyoleanolic acid (3-AOA) and 3-acetoxy, 28-methylester oleanolic acid (3-A,28-MOA). Anti-inflammatory properties of these compounds were assessed using the serotonin and fresh egg albumin-induced inflammatory test models in male Wistar rats weighing 250-300 g. Furthermore, erythrocyte membrane-stabilizing property of these compounds was evaluated in the heat- and hypotonicity-induced in vitro hemolysis test models. The two semisynthetic compounds significantly (p < 0.05) inhibited albumin-induced inflammation better than OA and indomethacin from 1-5 h post administration. Both compounds were membrane stabilizing in heat-induced hemolysis test while only 3-AOA showed membrane-stabilizing effects in a hypotonic milieu. Semisynthesis of OA yielded two compounds which had better in vivo anti-inflammatory and in vitro membrane-stabilizing properties.

Investigation of the antinociceptive and anti-inflammatory properties of Heteromorpha arborescens (Apiaceae).

Heteromorpha arborescens belongs to the family Apiaceae. It is commonly known as the parsley tree. One of its uses in the Eastern Cape Province of South Africa is for the treatment of abdominal pains. The therapeutic effects of the methanolic and aqueous root extracts of H. arborescens were investigated at two dose levels respectively on experimental models of pain and inflammation in rodents. The antinociceptive activity was evaluated using the hot-plate, abdominal constriction and formalin tests. The anti-inflammatory properties of these extracts were assessed using albumin and carrageenan as phlogistic agents. Both extracts produced significant (P<0.05, P<0.01) inhibition of thermal nociception induced by a hot plate. On chemical nociception induced by intraperitoneal acetic acid and subplantar formalin injection, both extracts significantly (P<0.05, P<0.01) decreased the number of writhing episodes and the licking time in a dose dependent manner. Treatment with the extracts at the same doses produced a significant (P<0.05, P<0.01) pain inhibition of the carrageenan induced inflammatory pain. Similarly, both extracts produced a significant (P<0.05, P<0.01) reduction of edema induced by albumin and carrageenan. These results suggest that both extracts of H. arborescens may act by inhibition of the mediators of inflammation. These findings seem to justify the use of the plant in traditional medicine in the management of pain and inflammation related diseases.