Antidiabetic and wound healing effects of smeathxanthone A

Wound healing is a natural and spontaneous phenomenon that takes place in three orderly and timely interactive phases: inflammation, proliferation, and remodelling. Normal wound healing cascade begins immediately following injury. Tissue damage and the activation of clotting factors during the vascular phase stimulate the release of inflammatory mediators, such as prostaglandins and histamine, from cells such as mast cells. The transition from the inflammatory to the proliferative phase, the stage characterized by the filling of the wound with new connective tissues, is orchestrated by macrophages. A decrease in wound size is achieved by a combination of the physiological processes of granulation, contraction, and epithelialization. Reepithelialization phase rebuilds the structure while the remodeling phase involves the final form. Surgery in diabetic patients is associated with slow wound healing process and hence requiring longer hospital stay, higher health care resource utilization, and greater perioperative mortality than nondiabetic subjects. The exact pathogenesis of the poor wound healing process in diabetic patients is not clearly understood, but evidence from studies involving both human and animal models reveal increased rate of infections and several abnormalities in the various phases of wound healing process. With the worldwide diabetes incidence now considered to be increasing in an epidemic proportion, there is a growing need to search for novel drugs to combat diabetes and the associated disorders, such as wound complications. Over 278 natural xanthones belonging to the plant families of Gentianaceae, Guttiferae, Moraceae, Clusiaceae, and Polygalaceae are known to occur. Most xanthones are polyphenols and hence regarded as powerful antioxidants that can offer beneficial health effect either by direct scavenging of reactive oxygen species or by acting as chain-breaking peroxyl radical scavengers. In addition to possessing antioxidant effects, xanthones have also been reported to be hepatoprotective, mutagenic, immunomodulatory, anticomplement, cardioprotective, antitumoral, antidiabetic, anti-inflammatory, antiulcer, and analgesic agents. Smeathxanthone A is a unique xanthone that combines a polyphenolic skeleton with four free hydroxyl groups and a terpenoid geranyl structural moiety. Although the compound has previously been isolated in our laboratories from Garcinia smeathmanii, it has never been investigated for its potential antidiabetic properties. In the present communication, the blood glucose lowering and wound healing effects of smeathxanthone A in diabetic mice are reported

Antioxidant benzophenones and xanthones from the root bark of Garcinia smeathmannii

A new geranylated xanthone (1) was isolated from the root bark extract of Garcinia smeathmannii Oliver along with known guttiferone I, isoxanthochymol, smeathxanthones A and B, and triacontanyl caffeate. The structures of these compounds were elucidated by spectral analysis and by comparison with the reported data. These compounds showed significant antioxidant DPPH radical scavenging activities.   KEY WORDS: Garcinia smeathmanii, Xanthone, Antioxidant  Bull. Chem. Soc. Ethiop. 2006, 20(2), 247-252

Polyanxanthone A, B and C, three xanthones from the wood trunk of Garcinia polyantha Oliv.

Three xanthones, polyanxanthone A (1), B (2) and C (3) have been isolated from the methanol extract of the wood trunk of Garcinia polyantha, along with five known xanthones: 1,3,5-trihydroxyxanthone (4); 1,5-dihydroxyxanthone (5); 1,3,6,7-tetrahydroxyxanthone (6); 1,6-dihydroxy-5-methoxyxanthone (7) and 1,3,5,6-tetrahydroxyxanthone (8). Their structures were determined by means of 1D- and 2D-NMR techniques. Some of the above compounds were screened for their anticholinesterase activity on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes.info:eu-repo/semantics/publishedVersio

A Subset of Patients With Autism Spectrum Disorders Show a Distinctive Metabolic Profile by Dried Blood Spot Analyses

Autism spectrum disorder (ASD) is currently diagnosed according to behavioral criteria. Biomarkers that identify children with ASD could lead to more accurate and early diagnosis. ASD is a complex disorder with multifactorial and heterogeneous etiology supporting recognition of biomarkers that identify patient subsets. We investigated an easily testable blood metabolic profile associated with ASD diagnosis using high throughput analyses of samples extracted from dried blood spots (DBS). A targeted panel of 45 ASD analytes including acyl-carnitines and amino acids extracted from DBS was examined in 83 children with ASD (60 males; age 6.06 ± 3.58, range: 2–10 years) and 79 matched, neurotypical (NT) control children (57 males; age 6.8 ± 4.11 years, range 2.5–11 years). Based on their chronological ages, participants were divided in two groups: younger or older than 5 years. Two-sided T-tests were used to identify significant differences in measured metabolite levels between groups. Näive Bayes algorithm trained on the identified metabolites was used to profile children with ASD vs. NT controls. Of the 45 analyzed metabolites, nine (20%) were significantly increased in ASD patients including the amino acid citrulline and acyl-carnitines C2, C4DC/C5OH, C10, C12, C14:2, C16, C16:1, C18:1 (P: < 0.001). Näive Bayes algorithm using acyl-carnitine metabolites which were identified as significantly abnormal showed the highest performances for classifying ASD in children younger than 5 years (n: 42; mean age 3.26 ± 0.89) with 72.3% sensitivity (95% CI: 71.3;73.9), 72.1% specificity (95% CI: 71.2;72.9) and a diagnostic odds ratio 11.25 (95% CI: 9.47;17.7). Re-test analyses as a measure of validity showed an accuracy of 73% in children with ASD aged ≤ 5 years. This easily testable, non-invasive profile in DBS may support recognition of metabolic ASD individuals aged ≤ 5 years and represents a potential complementary tool to improve diagnosis at earlier stages of ASD development

Modulating RNA structure and catalysis: lessons from small cleaving ribozymes

RNA is a key molecule in life, and comprehending its structure/function relationships is a crucial step towards a more complete understanding of molecular biology. Even though most of the information required for their correct folding is contained in their primary sequences, we are as yet unable to accurately predict both the folding pathways and active tertiary structures of RNA species. Ribozymes are interesting molecules to study when addressing these questions because any modifications in their structures are often reflected in their catalytic properties. The recent progress in the study of the structures, the folding pathways and the modulation of the small ribozymes derived from natural, self-cleaving, RNA motifs have significantly contributed to today’s knowledge in the field

The interface between health systems and vertical programmes in Francophone Africa : the managers' perceptions

Objective  To explores the interface between vertical programmes (VPs) and general health services (GHS) in sub-Saharan Africa. Methods  Using semi-structured interviews, we analysed the perceptions of a selection of experienced mid-level managers of health systems and of VP originating in francophone Africa on the nature and quality of this interface. Results  The respondents acknowledged that VPs lead to both positive and negative effects on the functioning of GHS. The overall result, however, cannot be viewed as a simple summation of the positive effects possibly compensating for the negative ones. Indeed, some of the negative effects have a profound impact on the management and operation of the health care delivery system and may undermine the long-term institutional capacity of the general health systems. The quality and the nature of the interface between VP and GHS strongly vary in time, between settings and programmes. Conclusion  We argue for more systematic monitoring of the interface between VP and GHS, so as to identify and address, in a timely manner, significant disruptive effects and deficiencies in a perspective of systemic capacity building of health systems

The interface between the national tuberculosis control programme and district hospitals in Cameroon: missed opportunities for strengthening the local health system -a multiple case study

BACKGROUND: Tuberculosis remains a major public health problem in sub-Saharan Africa. District hospitals (DHs) play a central role in district-based health systems, and their relation with vertical programmes is very important. Studies on the impact of vertical programmes on DHs are rare. This study aims to fill this gap. Its purpose is to analyse the interaction between the National Tuberculosis Control Programme (NTCP) and DHs in Cameroon, especially its effects on the human resources, routine health information system (HIS) and technical capacity at the hospital level. METHODS: We used a multiple case study methodology. From the Adamaoua Region, we selected two DHs, one public and one faith-based. We collected qualitative and quantitative data through document reviews, semi-structured interviews with district and regional staff, and observations in the two DHs. RESULTS: The NTCP trained and supervised staff, designed and provided tuberculosis data collection and reporting tools, and provided anti-tuberculosis drugs, reagents and microscopes to DHs. However, these interventions were limited to the hospital units designated as Tuberculosis Diagnostic and Treatment Centres and to staff dedicated to tuberculosis control activities. The NTCP installed a parallel HIS that bypassed the District Health Services. The DH that performs well in terms of general hospital care and that is well managed was successful in tuberculosis control. Based on the available resources, the two hospitals adapt the organisation of tuberculosis control to their settings. The management teams in charge of the District Health Services are not involved in tuberculosis control. In our study, we identified several opportunities to strengthen the local health system that have been missed by the NTCP and the health system managers. CONCLUSION: Well-managed DHs perform better in terms of tuberculosis control than DHs that are not well managed. The analysis of the effects of the NTCP on the human resources, HIS and technical capacity of DHs indicates that the NTCP supports, rather than strengthens, the local health system. Moreover, there is potential for this support to be enhanced. Positive synergies between the NTCP and district health systems can be achieved if opportunities to strengthen the district health system are seized. The question remains, however, of why managers do not take advantage of the opportunities to strengthen the health system

Trente ans de lutte antituberculeuse au Cameroun : une alternance entre systèmes d’offre de soins de santé « vertical » et « horizontal »

Position du problème : En Afrique sub-saharienne, la tuberculose reste endémique en dépit des réformes des systèmes de santé et de l’organisation de la lutte antituberculeuse entreprises ces dernières décennies. Méthodes : Nous avons procédé à une étude rétrospective de la lutte antituberculeuse au Cameroun dans la période 1980–2009. Les données ont été collectées à partir des documents et des rapports d’activités sur le contrôle de la tuberculose, et d’entretiens avec des responsables du Programme national de lutte contre la tuberculose. Résultats : L’histoire de la lutte antituberculeuse au Cameroun dans la période 1980–2009 peut se décliner en trois grandes périodes. La première va de 1980 à 1994 et correspond à la mise en œuvre de la politique ‘des soins de santé primaires’. Les soins antituberculeux étaient gratuits, mais centralisés au niveau de services spécialisés. La détection des nouveaux cas a augmenté de façon progressive mais modeste. Dans la deuxième période de 1995 à 2000, la politique de ‘réorientation des soins de santé primaires’ a introduit le recouvrement des coûts et a décentralisé la prise en charge de la tuberculose à toutes les formations sanitaires. En revanche, le Programme national de lutte contre la tuberculose, créé en 1996, a désigné les formations sanitaires – centres de diagnostic et de traitement –, autorisées à offrir les soins antituberculeux. Dans la troisième période, de 2001 à 2009, d’importants appuis venant des initiatives globales de santé ont permis d’augmenter le nombre de centres de diagnostic et de traitement (216 centres en 2009) et d’améliorer significativement la détection de nouveaux cas, qui a malheureusement stagné après 2006. Conclusion : Les indicateurs de prise en charge de la tuberculose au Cameroun n’ont jamais été optimaux entre 1980 et 2009 malgré leur évolution globalement positive. La stratégie des centres de diagnostic et de traitement, nichés essentiellement dans les hôpitaux, semble avoir atteint ses limites intrinsèques. Une meilleure performance de la lutte antituberculeuse nécessitera une décentralisation de la prise en charge vers les centres de santé. Cette décentralisation minutieuse améliorerait l’accès des patients tuberculeux aux soins et une meilleure utilisation de l’expertise technique de l’hôpital pour la prise en charge de la tuberculose.Thirty years of tuberculosis control in Cameroon: Alternating “vertical” and “horizontal” health care delivery systems BACKGROUND: In sub-Saharan Africa, tuberculosis remains endemic despite reforms of health systems and the tuberculosis control organization carried out in the last decades. METHODS: We conducted a retrospective study of tuberculosis control in Cameroon from the period 2009 back to 1980. Data were collected from documents and activity reports of tuberculosis control, and interviews with managers of the National tuberculosis control program. FINDINGS: The history of tuberculosis control in Cameroon from 2009 back to 1980 can be divided into three main periods. The first period, from 1980 to 1994, corresponded to the implementation of the 'primary health care' policy. At that time, tuberculosis case management was delivered free of charge, but centralized in specialized services with a gradual and mild increase in new cases detected. The second period, from 1995 to 2000, was characterized by the implementation of the 'primary health care reorientation' policy that decentralized tuberculosis care to all health facilities, but introduced cost recovery --which came along with a dramatic drop in the number of tuberculosis cases detected. The National tuberculosis control program, established in 1996, entrusted health facilities--especially hospitals--with the responsibility of tuberculosis diagnosis and treatment, and referred to them as tuberculosis diagnosis and treatment centers. During the third period, from 2001 to 2009, owing to major support from global health initiatives, the number of tuberculosis diagnosis and treatment centers was increased (reaching 216 centers in 2009), with a significant increase of new cases detected that peaked in 2006, from where the situation started declining till 2009. CONCLUSION: Tuberculosis control indicators have never been optimal in Cameroon, despite the generally positive trend from 1980 to 2009. The strategy of tuberculosis diagnosis and treatment centers, which are essentially nested within hospitals, seems to have reached its intrinsic limitations. Better performance in tuberculosis control will henceforth require greater decentralization of tuberculosis detection and treatment to health centers. This careful decentralization will improve access for tuberculosis patients and lead to a comprehensive use of hospital technical expertise for tuberculosis care

A systematic review of missed opportunities for improving tuberculosis and HIV/AIDS control in Sub-saharan Africa: what is still missed by health experts?

In sub-Saharan Africa, HIV/AIDS and tuberculosis are major public health problems. In 2010, 64% of the 34 million of people infected with HIV were reported to be living in sub-Saharan Africa. Only 41% of eligible HIV-positive people had access to antiretroviral therapy (ART). Regarding tuberculosis, in 2010, the region had 12% of the world's population but reported 26% of the 8.8 million incident cases and 254000 tuberculosis-related deaths. This paper aims to review missed opportunities for improving HIV/AIDS and tuberculosis prevention and care. We conducted a systematic review in PubMed using the terms 'missed'(Title) AND 'opportunities'(Title). We included systematic review and original research articles done in sub-Saharan Africa on missed opportunities in HIV/AIDS and/or tuberculosis care. Missed opportunities for improving HIV/AIDS and/or tuberculosis care can be classified into five categories: i) patient and community; ii) health professional; iii) health facility; iv) local health system; and v) vertical programme (HIV/AIDS and/or tuberculosis control programmes). None of the reviewed studies identified any missed opportunities related to health system strengthening. Opportunities that are missed hamper tuberculosis and/or HIV/AIDS care in sub-Saharan Africa where health systems remain weak. What is still missing in the analysis of health experts is the acknowledgement that opportunities that are missed to strengthen health systems also undermine tuberculosis and HIV/AIDS prevention and care. Studying why these opportunities are missed will help to understand the rationales behind the missed opportunities, and customize adequate strategies to seize them and for effective diseases control