Nutrition-induced catch-up growth increases hypoxia inducible factor 1alpha RNA levels in the growth plate

Although catch-up growth is a well-known phenomenon, the local pathways at the epiphyseal growth plate that govern this process remain poorly understood. To study the mechanisms governing catch-up growth in the growth plate, we subjected prepubertal rats to 10 days of 40% food restriction, followed by a renewal of the regular food supply to induce catch-up growth. The animals were weighed daily, and their humeral length was measured at sacrifice. The proximal tibial epiphyseal growth plates (EGPs) were studied, and findings were compared with EGPs from animals fed ad libitum and animals under food restriction. The gene expression profile in the growth plates was examined using DNA microarrays, and the expression levels of selected genes were validated by real-time polymerase chain reaction. To localize gene expression in different growth plate zones, microdissection was used. Protein levels and localization were examined using immunohistochemistry. We showed that the expression level of 550 genes decreased during food restriction and increased during catch-up growth, starting already one day after refeeding. HIF-1alpha, as well as several of its downstream targets, was found among these genes. Immunohistochemistry showed a similar pattern for HIF-1alpha protein abundance. Additionally, HIF-1alpha mRNA and protein levels were higher in the proliferating than in the hypertrophic zone, and this distribution was unaffected by nutritional status. These findings indicate that nutrition has a profound effect on gene expression level during growth plate growth, and suggest an important role for HIF-1alpha in the growth plate and its response to nutritional manipulation.

Comparison of 4% articaine and 0.5% levobupivacaine/2% lidocaine mixture for sub-Tenon's anaesthesia in phacoemulsification cataract surgery: a randomised controlled trial

BACKGROUND/AIMS

[corrected] The aim of this study was to compare the efficacy and safety of 4% articaine with a mixture containing equal volumes of 2% lidocaine and 0.5% levobupivacaine without hyaluronidase for sub-Tenon's anaesthesia in phacoemulsification cataract surgery.

METHODS

The study was a prospective, randomised double-masked clinical trial of 65 patients allocated to receive either 4% articaine or a mixture containing equal parts of 2% lidocaine and 0.5% levobupivacaine. All patients had pre- and postoperative Hess charting to document ocular motility dysfunction. Ocular and eyelid movements were scored at 2 min intervals from 2 to 10 min after injection of the anaesthetic agent, and at the end of surgery. Complications related to injection, including pain, chemosis and subconjunctival haemorrhage, were recorded. Patients rated pain (none/mild/moderate/severe) during surgery. The operating surgeon masked to the anaesthetic agent assessed proptosis/chemosis at the start of the operation and the degree of ocular akinesia and analgesia at the end of surgery.

RESULTS

The articaine group demonstrated a rapid onset of ocular akinesia with a mean time to readiness for surgery (achieving a score of </=5) of 4.0 min compared with 10 min for the lidocaine/levobupivacaine group (p = 0.001). The effectiveness of block was significantly greater in the articaine group at all points (p<0.01). Surgeons rated ocular akinesia to be superior in the articaine group (p<0.001). Patients and surgeons rated the analgesic effect as comparable in either group. Eyelid scores, subconjunctival haemorrhage and chemosis were comparable in either group. Hess chart was performed on all patients pre- and postoperatively. There was no clinically significant motility disturbance in the articaine group, whereas one patient in the lidocaine/levobupivacaine group developed diplopia with abnormal ocular motility on the Hess chart.

CONCLUSION

Articaine (4%) is a safer and a superior anaesthetic agent than a mixture of 2% lidocaine and 0.5% levobupicaine in achieving ocular akinesia for sub-Tenon's block in phacoemulsification cataract surgery.

High expression of RelA/p65 is associated with activation of nuclear factor-kappaB-dependent signaling in pancreatic cancer and marks a patient population with poor prognosis

Activation of nuclear factor-kappaB (NF-kappaB) signaling was observed in pancreatic adenocarcinoma cell lines and tumours. However, information on the expression of RelA/p65, the major transcription activating NF-kappaB subunit, in these carcinomas and possible correlations thereof with NF-kappaB activation and patient survival is not available. To provide this missing translational link, we analysed expression of RelA/p65 in 82 pancreatic adenocarcinomas by immunohistochemistry. Moreover, we measured activation of the NF-kappaB pathway in 11 tumours by quantitative PCR for NF-kappaB target genes. We observed strong cytoplasmic or nuclear expression of RelA/p65 in 42 and 37 carcinomas, respectively. High cytoplasmic and nuclear expression of RelA/p65 had negative prognostic impact with 2-year survival rates for patients without cytoplasmic or nuclear RelA/p65 positivity of 41 and 40% and rates for patients with strong cytoplasmic or nuclear RelA/p65 expression of 22 and 20%, respectively. High RelA/p65 expression was correlated to increased expression of NF-kappaB target genes. The observation that high expression of RelA/p65 is correlated to an activation of the NF-kappaB pathway and indicates poor patient survival identifies a patient subgroup that might particularly benefit from NF-kappaB-inhibiting agents in the treatment of pancreatic cancer. Based on our findings, this subgroup could be identified by applying simple immunohistochemical techniques.

CETUFTIRI, a new combination of UFT with leucovorin (LV), irinotecan, and cetuximab as first-line treatment for patients (pts) with unresectable metastatic colorectal cancer (mCRC): Preliminary results from a multicenter phase II trial

4087

Background: A phase II study (ASCO 2004) established that the combination of UFT (tegafur-uracil) with LV and irinotecan (TEGAFIRI) could be safely administered to pts with unresectable mCRC, with an objective response rate (ORR) of 34% and a median time to progression (TTP) of 5.7 months. We initiated CETUFTIRI, a phase II study, to evaluate the efficacy and tolerability of cetuximab added to TEGAFIRI in chemonaïve pts with unresectable mCRC. Methods: Patients in this single-stage study were aged =18 years, with histologically or cytologically confirmed, bidimensionally measurable mCRC, ECOG performance status 0 or 1, and adequate bone marrow, renal, and hepatic function. EGFR expression was not an inclusion criterion. Treatment consisted of UFT 250 mg/m2/day d1–14, LV 90 mg/day d1–14, and irinotecan 250 mg/m2 d1 every 3 weeks, plus cetuximab 400 mg/m2 week 1 then 250 mg/m2 weekly thereafter. The primary endpoint was ORR and the planned sample size was 61 pts. The study is now closed to accrual. Results: To date, 48 patients are evaluable for safety and 31 are evaluable for efficacy. Patient characteristics (n=48): median age 65 years (range 45–84 years); ECOG PS 0/1: 73/27%; male 65%; tumor sites: colon 69%; rectum 17%; junction 14%; liver metastasis 83%; lung metastasis 46%; other 27%. Adverse events per patient (n=48) after a total of 230 cycles were: grade G3 mucositis 10%; G3/4 neutropenia 10%; G3 nausea/vomiting 8%; G3 asthenia 6%; febrile neutropenia 6%; G3 hypokalemia 6%; G3/4 anemia 4%; G3 diarrhea 2%; acne-like rash G1/2 50% (G3 4%); infusion- related reaction to cetuximab 6%. Two of 31 evaluable pts had a complete response and 11 had a partial response, for an ORR of 42%; 5 pts had stable disease (16%) and 11 pts had progressive disease (35.5%). An independent radiologist review is planned for all 61 pts included up to December 2006. Conclusions: The CETUFTIRI combination seems to have an acceptable toxicity profile with an attractive objective response rate in the first-line treatment of pts with mCRC.

No significant financial relationships to disclose.

Viper bite with continuous defibrination despite adequate treatment with antivenom

A case of envenomation due to viperine snakebite poisoning is presented. Patient showed continuous defibrination, without any other signs of poisoning, which could not be reversed with more than double the usual dose of polyvalent antivenom. This phenomenon could be due to envenomation caused by a snake, probably from Viperidae family, which is not covered by the polyvalent antivenom available in India.

A randomized phase II trial evaluating safety and efficacy of an experimental chemotherapy regimen (CPT-11 + oxaliplatin [IRINOX]) and two standard arms (LV5-FU2 + CPT-11 [FOLFIRI], LV5-FU2 + oxaliplatin [FOLFOX]) in first line metastatic colorectal cancer (MCRC) (FNCLCC Accord 08)

3586

Background: LV5-FU2 + CPT-11 or oxaliplatin (OHP) are standard therapies in first line MCRC. This phase II trial evaluates an experimental regimen of CPT-11 + oxaliplatin, without 5FU. Methods: First line MCRC evaluable patients (pts) were randomized to receive, every two weeks, either: Arm A = OHP 85 mg/m2 d1 followed by CPT-11 180 mg/m2 (IRINOX), or Arm B = simplified LV5-FU2 (leucovorin 200 mg/m2 as a 2 h-infusion d1, 5FU bolus 400 mg/m2 d1, and 5FU continuous infusion 2400 mg/m2 d1–2) and CPT-11 180 mg/m2 d1 (FOLFIRI), or simplified LV5-FU2 and OHP 85 mg/m2 d1 (FOLFOX). Results were combined for the two standard arms (FOLFIRI + FOLFOX). Results: 80 pts were included between 09/2002 and 04/2005, 40 in IRINOX (arm A), 20 each in FOLFIRI and FOLFOX (arm B). Pts characteristics (A:B): M/F = 27/13:29/11; median age (range): 63 (41–76):61 (47–75); PS (0/1/2): 16/21/3:16/22/2; median number of cycles (range): 8.0 (1–16):12 (1–26). Safety data: no toxic death. IRINOX (318 cycles): NCI G3–4 neutropenia, 43.6% (pts), 14.7% (cycles); G3–4 neurotoxicity, 17.9% (pts), 5.0% (cycles); G3–4 diarrhea, 33.3% (pts), 5.3% (cycles). FOLFIRI (238 cycles) and FOLFOX (186 cycles): G3–4 neutropenia, 40% (pts) and 23.8% (pts) respectively (8.8% and 7.6% of cycles); G3–4 neurotoxicity, 0% and 14.3% (pts), 0% and 2.7% (cycles); G3–4 diarrhea 15% and 0% (pts), 2.1% and 0% (cycles). Median relative dose-intensity was 0.86 (0.57–1.0) for CPT-11, 0.86 (0.57 -1.0) for OHP in the IRINOX arm. We observed 21 PR in the IRINOX arm, 19 PR and 2 CR in the 2 control arms, for an ORR = 52.5%, 90% CI (38–66). Median follow-up: 17 months, median PFS for IRINOX: 8.4 months. Conclusions: The combination of CPT-11 and OHP (IRINOX) at these doses, every 2 weeks, appears safe and active in first line MCRC.

[Table: see text]

Human selenoproteins at a glance

The public perception of selenium has changed significantly over the last decades. Originally mainly known for its high toxicity, it was later recognized as an essential trace element and is now (despite its narrow therapeutic window) almost being marketed as a lifestyle drug. Indeed, some clinical and preclinical studies suggest that selenium supplementation may be beneficial in a large number of clinical conditions. However, its mode of action is unresolved in most of these cases. Selenocysteine - identified as the 21st amino acid used in ribosome-mediated protein synthesis - is incorporated in at least 25 specific, genetically determined human selenoproteins, many of which have only recently been discovered. Restoration of normal selenoprotein levels may be - apart from direct supranutritional effects - one possible explanation for the effects of selenium supplements. In this review we provide a brief but up-to-date overview of what is currently known about these 25 acknowledged human selenoproteins and their synthesis.

Antimutagenic and anti-oxidant activities of the non-steroidal anti-inflammatory drug celecoxib

1. Tumors arise and progress through the accumulation of serial genetic changes, including successive mutations, which involve activation of proto-oncogenes and inactivation of tumour suppressor genes, leading to the uncontrolled proliferation of progeny cells. The human body is continuously and unavoidably exposed to structurally diverse chemicals with established carcinogenic activity in animal models and/or mutagenic activity in short-term tests. 2. Celecoxib, a non-steroidal anti-inflammatory drug that specifically inhibits the enzyme cyclo-oxygenase-2, has been reported to be effective against certain types of cancers. The in vitro anti-oxidant and antimutagenic activities of the celecoxib were investigated in the present study using standard procedures. 3. The antimutagenic activity of celecoxib was determined using histidine mutant Salmonella typhimurium strains TA98, TA100, TA102 and TA1535 against directly acting mutagens (sodium azide (NaN3), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), 4-nitro-o-phenylenediamine (NPDA) and doxorubicin) and mutagens needing activation (2-acetamidofluorene (2-AF) and 7,12-dimethylbenz [a] anthracene (DMBA)). 4. Celecoxib inhibited NaN3-, MNNG- and NPDA-induced mutations of TA100. The antimutagenicity of celecoxib (0.2 mg/plate) against the NaN3-induced mutation of TA1535 was 39.8% (P < 0.001). The MNNG-induced mutation of TA1535 was also inhibited by 0.3 mg/plate celecoxib (46.0%; P < 0.05). At concentrations of 0.2 mg/plate, celecoxib significantly inhibited NPDA- and doxorubicin-induced mutations of TA98 by 52.5 and 58.0%, respectively (P < 0.001 and P < 0.05, respectively). 5. The antimutagenic activity of 0.3 mg/plate celecoxib against 2-AF- and DMBA-induced mutations of TA98 was 81.76 and 98.1%, respectively (P < 0.001). 6. The anti-oxidant activity of celecoxib was determined by the inhibition of lipid peroxidation and superoxide and hydroxyl radical-scavenging activities. 7. The IC50 values of celecoxib for hydroxyl radical-scavenging and the inhibition of lipid peroxidation were 1.97 +/- 0.06 and 1.99 +/- 0.05 micromol/mL, respectively. Celecoxib had no superoxide radical scavenging-activity up to a concentration of 2.6 micromol/mL. 8. The in vitro antimutagenic and anti-oxidant activities of celecoxib indicate its possible therapeutic use as a cancer chemopreventive agent.

In vitro and in vivo characterization of smooth small colony variants of Brucella abortus S19

Brucella abortus is known to produce chronic infections in both humans and a variety of animal species. However, the mechanisms underlying the persistence of the bacteria in the presence of an ongoing immune response are still unknown. In this respect we made use of the observation that in vitro grown B. abortus S19 exhibits heterogenicity in colony size when plated onto TS agar, while experimental infection of mice uniformly results in the in vivo selection of the small colony variant. We demonstrate that the spontaneous smooth small colony variant is characterized not only by a slower growth rate in vitro but also by an increased tolerance to hyperosmotic medium and, most importantly, a less effective clearance from spleens and livers of experimentally infected mice. On a molecular level, a gene with homology to a formerly described galactoside transport ATP binding protein (mglA) was differentially expressed in small versus large colonies of B. abortus S19.

Mydriasis due to Datura inoxia

Unilateral, dilated unresponsive pupil may be secondary to a wide range of ocular and neurological disorders. "Gardener's pupil" is a pharmacological mydriasis caused by exposure to plants containing alkaloids. We report a case of mydriasis related to Datura inoxia, and detail a number of plants that have toxic effects. This report emphasises the importance of accurate history taking when evaluating fixed dilated pupil. We recommend that labelling of such poisonous plants should detail the local and systemic effects of accidental exposure, rather than merely the fact that they are poisonous.

Induction of gene expression of xenobiotic metabolism enzymes and ABC-transport proteins by PAH and a reconstituted PAH mixture in human Caco-2 cells

It was shown recently that in epithelial Caco-2 cells the food contaminant benzo[a]pyrene (B[a]P) is metabolized and B[a]P-sulfate metabolites were transported out of the cells. The aim of this study was to investigate whether B[a]P and other polycyclic aromatic hydrocarbons (PAH) such as chrysene, phenanthrene, benzo[k]fluoranthene (B[k]F), dibenzo[a,l]pyrene (DB[a,l]P), and pyrene alone or in a mixture in a ratio as they occur in tobacco smoke have effects on gene expression of intestinal cytochrome P450 enzymes (CYP), Phase II enzymes and ATP-binding cassette (ABC)-transport proteins in the human Caco-2 cells. B[a]P induced its own metabolism. Treatment of the Caco-2 cells with B[a]P, chrysene, B[k]F, or DB[a,l]P induced mRNA expression of CYP1A1 and CYP1B1 specifically as measured by RT-PCR. In contrast, the mRNA expression of the microsomal epoxide hydrolase (mEH) was not affected by PAH. The gene expression of the Phase II enzymes UDP-glucuronosyltransferase 1A6 (UGT1A6) and UGT1A7 was also induced by these PAH but treatment with them had no effect on gene expression of sulfotransferases (SULT) at all. Of the ABC-transport proteins, MDR1 mRNA expression was induced by treatment with carcinogenic PAH, whereas MRP2 mRNA expression was not changed. The mixture of PAH also induced CYP1A1, CYP1B1, UGT1A6, and UGT1A7 mRNA expression. We conclude that B[a]P, chrysene, B[k]F, and DB[a,l]P have specific effects on intestinal CYP1A1, CYP1B1, UGT1A6, and UDP1A7 mRNA expression but no effects on the expression of SULT.

Clinical and laboratory features and response to treatment in patients presenting with vitamin B12 deficiency-related neurological syndromes

AIMS AND OBJECTIVES

To study the clinical and laboratory features of patients admitted with vitamin B12 deficiency-related (B12def) neurological syndromes.

SETTINGS AND DESIGN

A hospital-based retrospective and prospective study conducted at a referral teaching hospital.

MATERIALS AND METHODS

Consecutive patients admitted with vitamin B12 deficiency-related neurological disorders during a three-year period from June 2000 to May 2003 were included. Data regarding clinical and laboratory features were obtained. Follow-up was done at least six months following treatment with parenteral vitamin B12. Chi-square test was used for statistical analysis.

RESULTS

A total of 63 patients (52 males) with a mean age of 46.2 years were studied. The mean duration of symptoms at presentation was 10.3 months. Myeloneuropathy (54%) was the commonest neurological manifestation, followed by myeloneuropathy with cognitive dysfunction (34%), and peripheral neuropathy (9%). Neuropsychiatric manifestations and dementia were observed in 38% and 19% of patients respectively. All the patients had megaloblastic changes in the bone marrow smear. Eleven (17.5%) patients had both hemoglobin and the mean corpuscular volume (MCV) within the normal range. Follow-up after at least six months of therapy with parenteral B12 showed improvement in 54% patients.

CONCLUSIONS

A high index of suspicion of B12def is required in patients presenting with myelopathy, cognitive decline, or neuropathy. A normal hemoglobin or MCV does not exclude B12def; therefore, other tests such as bone marrow smear and serum vitamin B12 assay are essential, as the condition is often reversible with treatment.

Variability in the extent of sensory deficit after sural nerve biopsy

BACKGROUND

Sural nerve biopsy (SNBx) is associated with multiple complications such as paresthesia, pain, or numbness in the sural nerve distribution at the site of biopsy and wound infection. An accurate idea of these adverse events would be useful while taking informed consent from patients.

AIMS

We conducted a prospective study to determine the extent of sensory deficits after SNBx.

SETTINGS AND DESIGN

It is a prospective, hospital-based (tertiary teaching hospital) study.

MATERIALS AND METHODS

All the patients who had SNBx between May 2003 and March 2004 were eligible for inclusion. However, patients with sensory impairment in sural nerve territory or abnormal sural nerve conduction studies prior to the procedure were excluded. SNBx was performed in the ankle region under local anesthesia, and a 3 cm nerve segment was excised. Touch, pain, temperature, vibration and joint position were tested after the nerve biopsy. The extent of sensory deficit was determined. Any other complications, when present were also noted. Follow-up assessment was performed at three months or later.

RESULTS

Fifty patients (26 women) fulfilled the inclusion and exclusion criteria. The mean age was 37.4 (16-63) years. One-two weeks after the SNBx, 46 (92%) patients had sensory deficit along the lateral aspect of the foot at the site of the biopsy, and 48 (96%) patients had sensory impairment extending beyond the outer aspect of the fifth toe. At follow-up, sensory deficit was present in 89% patients and paresthesia in 39%.

CONCLUSIONS

The majority of the patients undergoing SNBx develop persistent sensory deficits, which often extend beyond the typical sural nerve territory.