Antioxidant and lipophilic constituents of Tinospora crispa

TLC autographic assays revealed in the CH(2)Cl(2) extract of Tinospora crispa Miers (Menispermaceae) the presence of three compounds exhibiting antioxidant and radical scavenging properties towards beta-carotene and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. They were isolated and identified as N-CIS-feruloyltyramine, N-trans-feruloyltyramine and secoisolariciresinol. When tested in dilution assays on the reduction of the DPPH radical, these 3 compounds proved to be more active than the synthetic antioxidant butylhydroxytoluene (BHT). Further investigation of the CH(2)Cl(2) extract led to the isolation of vanillin, syringin, the alkaloid N-formylnornuciferin and the diterpene derivatives borapetosides B and C. In addition, a LC/UV/MS analysis enabled the on-line identification of borapetoside F and N-formylannonain.     

Chronic complications and quality of life of patients living with sickle cell disease and receiving care in three hospitals in Cameroon: a cross-sectional study

Background

Sickle Cell Disease (SCD) is associated with chronic multisystem complications that significantly influence the quality of life (QOL) of patients early in their life. Although sub-Saharan Africa bears 75% of the global burden of SCD, there is a paucity of data on these complications and their effects on the QOL. We aimed to record these chronic complications, to estimate the QOL, and to identify the corresponding risk factors in patients with SCD receiving care in three hospitals in Cameroon.

Methods

In this cross-sectional study, a questionnaire was used to collect data from consecutive consenting patients. Information recorded included data on the yearly frequency of painful crisis, the types of SCD, and the occurrence of chronic complications. A 36-Item Short Form (SF-36) standard questionnaire that examines the level of physical and mental well-being, was administered to all eligible participants. Data were analyzed with STATA® software.

Results

Of 175 participants included, 93 (53.1%) were female and 111 (aged ≥14 years) were eligible for QOL assessment. The median (interquartile range, IQR) age at diagnosis was 4.0 (2.0-8.0) years and the median (IQR) number of yearly painful crisis was 3.0 (1.0–7.0). The most frequent chronic complications reported were: nocturnal enuresis, chronic leg ulcers, osteomyelitis and priapism (30.9%, 24.6%, 19.4%, and 18.3% respectively). The prevalence of stroke and avascular necrosis of the hip were 8.0% and 13.1% respectively. The median (IQR) physical and mental scores were 47.3 (43.9–58.5) and 41.0 (38.8–44.6) respectively. Age and chronic complications such as stroke and avascular necrosis were independently associated with poor QOL.

Conclusions

In this population of patients living with SCD, chronic complications are frequent and their QOL is consequently poor. Our results highlight the need for national guidelines for SCD control, which should include new-born screening programs and strategies to prevent chronic complications.

     

MAPK-ERK activation in kidney of male rats chronically fed ochratoxin A at a dose causing a significant incidence of renal carcinoma

Kidney samples of male Fischer 344 (F-344) rats fed a carcinogenic dose of OTA over 7 days, 21 days and 12 months were analysed for various cell signalling proteins known to be potentially involved in chemical carcinogenicity. OTA was found to increase the phosphorylation of atypical-PKC. This was correlated with a selective downstream activation of the MAP-kinase extracellular regulated kinases isoforms 1 and 2 (ERK1/2) and of their substrates ELK1/2 and p90RSK. Moreover, analysis of effectors acting upstream of PKC indicated a possible mobilisation of the insulin-like growth factor-1 receptor (lGFr) and phosphoinositide-dependent kinase-1 (PDK1) system. An increased histone deacetylase (HDAC) enzymatic activity associated with enhanced HDAC3 protein expression was also observed. These findings are potentially relevant with respect to the understanding of OTA nephrocarcinogenicity. HDAC-induced gene silencing has previously been shown to play a role in tumour development. Furthermore, PKC and the MEK-ERK MAP-kinase pathways are known to play important roles in cell proliferation, cell survival, anti-apoptotic activity and renal cancer development.     

Circumvention of nuclear factor kappaB-induced chemoresistance by cytoplasmic-targeted anthracyclines

Nuclear factor kappaB (NF-kappaB) has been implicated in inducible chemoresistance against anthracyclines. In an effort to improve the cytotoxicity of anthracyclines while reducing their cardiotoxic effects, we have developed a novel class of extranuclear-localizing 14-O-acylanthracyclines that bind to the phorbol ester/diacylglycerol-binding C1b domain of conventional and novel protein kinase C (PKC) isoforms, thereby promoting an apoptotic response. Because PKCs have been shown to be involved in NF-kappaB activation, in this report, we determined the mechanism of NF-kappaB activation by N-benzyladriamycin-14-valerate (AD 198) and N-benzyladriamycin-14-pivalate (AD 445), two novel 14-O-acylanthracylines. We show that the induction of NF-kappaB activity in response to drug treatment relies on the activation of PKC-delta and NF-kappaB-activating kinase (NAK), independent of ataxia telengectasia mutated and p53 activities. In turn, NAK activates the IKK complex through phosphorylation of the IKK-2 subunit. We find that neither NF-kappaB activation nor ectopic expression of Bcl-X(L) confers protection from AD 198-induced cell killing. Overall, our data indicate that activation of novel PKC isoforms by cytoplasmic-targeted 14-O-acylanthracyclines promotes an apoptotic response independent of DNA damage, which is unimpeded by inducible activation of NF-kappaB.     

Regulation of alpha-fetoprotein by nuclear factor-kappaB protects hepatocytes from tumor necrosis factor-alpha cytotoxicity during fetal liver development and hepatic oncogenesis

Nuclear factor-kappaB (NF-kappaB) plays a critical role during fetal liver development and hepatic oncogenesis. Here, we have assessed whether NF-kappaB activity is required for murine hepatocellular carcinoma cell survival. We show that adenoviral-mediated inhibition of inhibitor of NF-kappaB kinase-beta (IKK-2) activity in hepatocellular carcinomas derived from transforming growth factor (TGF)-alpha/c-myc bitransgenic mice leads to inhibition of NF-kappaB and promotes tumor necrosis factor (TNF)-alpha-mediated cell death of malignant hepatocytes but not the surrounding peritumorous tissue. Induction of apoptosis is accompanied by inhibition of Bcl-X(L) and XIAP, two pro-survival NF-kappaB target genes. In addition, we have identified the alpha-fetoprotein (AFP) as a novel downstream target of NF-kappaB. We show that repression of IKK-2 activity in hepatocellular carcinomas promotes down-regulation of AFP gene expression. Likewise, genetic disruption of the RelA subunit results in reduced AFP gene expression during embryonic liver development, at a time in which fetal hepatocytes are sensitized to TNF-alpha-mediated cell killing. In this regard, we show that AFP inhibits TNF-alpha-induced cell death of murine hepatocellular carcinomas through association with TNF-alpha and inhibition of TNFRI signaling. Thus, NF-kappaB-mediated regulation of AFP gene expression during liver tumor formation and embryonic development of the liver constitutes a potential novel mechanism used by malignant and fetal hepatocytes to evade immune surveillance.     

Inhibition of CK2 activity by TGF-beta1 promotes IkappaB-alpha protein stabilization and apoptosis of immortalized hepatocytes

Nuclear factor kappaB (NF-kappaB) is an antiapoptotic factor involved in development, regeneration, and neoplastic progression of the liver. Previously, we have shown that stabilization of inhibitor kappaB (IkappaB)-alpha protein following treatment of hepatocytes with transforming growth factor (TGF)-beta1 promoted NF-kappaB repression, which then permitted induction of AP-1/SMAD-mediated liver cell death. Because basal IkappaB-alpha protein turnover is regulated by protein kinase CK2, here we have elucidated the regulation of CK2 kinase activity and its role in control of NF-kappaB levels following treatment with TGF-beta1. We show that both messenger RNA (mRNA) and protein levels of the CK2alpha catalytic subunit are down-regulated following TGF-beta1 stimulation in murine hepatocyte cells. The ensuing inhibition of CK2 kinase activity promotes stabilization of IkappaB protein, which is followed by the shutoff of constitutive NF-kappaB activity and induction of apoptosis. Ectopic expression of CK2alpha inhibits TGF-beta1-induced apoptosis through sustained activation of NF-kappaB. Conversely, expression of a kinase-dead mutant of CK2alpha potentiates TGF-beta1 cell killing. Importantly, we show that hepatocellular carcinomas (HCCs) derived from TGF-beta1 transgenic mice and human HCC cell lines display enhanced CK2 IkappaB kinase activity that contributes in part to an elevated NF-kappaB activity in vivo. In conclusion, inhibition of CK2 expression levels by TGF-beta1 is crucial for the induction of apoptosis of hepatocytes. Circumvention of this process by up-regulation of CK2 activity in transformed cells may contribute to the promotion of TGF-beta1-induced liver carcinogenesis.     

Agenesis of the gallbladder： A dangerously misdiagnosed malformation

Isolated agenesis of the gallbladder is a rare anomaly, often asymptomatic. However, one patient out of four presented with right upper abdominal pain, nausea, and fatty food intolerance. The condition is frequently mistaken with an excluded or sclero-atrophic gallbladder, regardless of the imaging modality used. Consequently, AG often leads to unnecessary and potentially dangerous laparoscopic surgery as described in a few case reports over the last 10 years. The aim of this study is to clarify the diagnostic and therapeutic approach of this unusual pathology. Two cases seen in our institutions were retrospectively reviewed, together with a review of the American and European literature. During laparoscopy, the absence of normal anatomical structures and the impossibility of pulling on the gallbladder to expose and dissect the triangle of Callot increases the risk of iatrogenic injury to biliary or portal structures. Depending on the experiment of the surgeon in laparoscopic procedure, this has to be taken into account to decide a conversion to laparotomy. A high index of suspicion is necessary when interpreting the radiological images. In case of doubt, a MRI-cholangiography is mandatory. Because of possible inherited transmission, relatives with a history of biliary symptoms should be investigated.     

The “least restrictive environment”: From Rhetoric to Practice

During the past 10 years, more and more general hospitals have opened psychiatric units, many of which represent the best of modern hospital psychiatry. Therapeutic success on these units is based on control of admissions as well as on clinical programs. Pressure from the State to admit involuntary patients, recently justified by the doctrine of the “least restrictive environment”, threatens to erode the quality of treatment now being provided. The concept of “least restrictive environment” is ambiguous and sometimes misleading. The treatment of involuntary psychiatric patients in general hospitals, in order to be safe and effective, requires the resolution of legal, clinical, financial, and architectural issues, as well as problems in the relationship between psychiatric units and other areas of the general hospital.