Cancer stem cell-like cells derived from malignant peripheral nerve sheath tumors

This study aims to examine whether or not cancer stem cells exist in malignant peripheral nerve sheath tumors (MPNST). Cells of established lines, primary cultures and freshly dissected tumors were cultured in serum free conditions supplemented with epidermal and fibroblast growth factors. From one established human MPNST cell line, S462, cells meeting the criteria for cancer stem cells were isolated. Clonal spheres were obtained, which could be passaged multiple times. Enrichment of stem cell-like cells in these spheres was also supported by increased expression of stem cell markers such as CD133, Oct4, Nestin and NGFR, and decreased expression of mature cell markers such as CD90 and NCAM. Furthermore, cells of these clonal S462 spheres differentiated into Schwann cells, smooth muscle/fibroblast and neurons-like cells under specific differentiation-inducing cultural conditions. Finally, subcutaneous injection of the spheres into immunodeficient nude mice led to tumor formation at a higher rate compared to the parental adherent cells (66% versus 10% at 2.5×10⁵). These results provide evidence for the existence of cancer stem cell-like cells in malignant peripheral nerve sheath tumors.

Neuro-kardio-fazio-kutane Syndrome

Neuro-kardio-fazio-kutane („neuro-cardio-facio-cutaneous“: NCFC) Syndrome wurden in den letzten Jahren als eine Gruppe von angeborenen Erkrankungen definiert, deren phänotypische Überschneidungen eine gemeinsame pathogenetische Grundlage haben. Erkrankungen aus diesem phänotypischen Spektrum gehen mit einer Überfunktion des RAS-MAPK-Signalwegs (RAS: „rat sarcoma“, MAPK mitogenaktivierte Proteinkinase) einher. Zu den neuro-kardio-fazio-kutanen Erkrankungen gehören das Noonan-, das LEOPARD-, das kardio-fazio-kutane („cardio-facio-cutaneous“: CFC) und das Costello-Syndrom, die Neurofibromatose Typ 1 sowie das Legius-Syndrom. Für eine sachgerechte medizinische Diagnostik und Behandlung sowie die notwendige psychosoziale Betreuung von Betroffenen und deren Familien ist das Zusammenwirken verschiedener Fachdisziplinen notwendig.

Comparison of laboratory colonies and field populations of Tamarixia radiata, an ectoparasitoid of the Asian citrus psyllid, using internal transcribed spacer and cytochrome oxidase subunit I DNA sequences

The genetic diversity of Tamarixia radiata Waterston (Hymenoptera: Eulophidae) laboratory colonies derived from collections in China, northern Vietnam, Pakistan, and a mixed colony from Taiwan and southern Vietnam was evaluated using the internal transcribed spacer (ITS) region 1, ITS-2, and the 5' end of the cytochrome oxidase subunit I gene. The strains share the same ITS sequence, consistent with the morphological hypothesis that the collections represent a single species. The COI marker was variable and could distinguish the northern Vietnam and Pakistan colonies from each other and from the other colonies. Comparison of COI sequences from field-collected populations of Puerto Rico, Guadeloupe, and Texas indicates that Florida is not a likely source of the introduction into Puerto Rico but is a likely source of the introduction into Texas.

Bevacizumab induces regression of vestibular schwannomas in patients with neurofibromatosis type 2

Bilateral vestibular schwannomas are the hallmark of neurofibromatosis type 2 (NF2), and these tumors impair hearing and frequently lead to deafness. Neurosurgical intervention, the only established treatment, often damages the vestibular nerve. We report 2 cases in which treatment with bevacizumab (for 3 months in one case and 6 months in the other) induced regression of progressive vestibular schwannomas by more than 40% and substantially improved hearing in the patient treated for 6 months. Bevacizumab therapy may thus provide an effective treatment for progressive vestibular schwannomas in patients with NF2.

CD4-BFFI: a novel, bifunctional HIV-1 entry inhibitor with high and broad antiviral potency

Resistance to antiretroviral drugs is a common problem in the treatment of HIV-1-infected patients. To overcome resistance, we generated a novel, bifunctional HIV-1 entry inhibitor by combining the anti-CD4 monoclonal antibody (mAb) 6314 with a fusion inhibitor similar to T-651 (anti-CD4 mAb based BiFunctional Fusion Inhibitor, CD4-BFFI). CD4-BFFI has potent antiviral activity against a multitude of HIV-1 isolates independent of their co-receptor usage and genetic background. It has higher antiviral potency compared to the fusion inhibitor T-651 or the anti-CD4 mAb 6314 used independently. More importantly, every HIV-1 strain tested was fully inhibited by CD4-BFFI while many strains were only partially inhibited by 6314. CD4-BFFI also retained antiviral potency against virus strains resistant to two fusion inhibitors, a CCR5 antagonist and an anti-CCR5 mAb. Pre-incubation of cells with a saturating concentration of anti-CD4 mAbs reduced the antiviral potency of CD4-BFFI, suggesting that binding of CD4-BFFI to the cell surface via its CD4 mAb portion is required for the antiviral potency of its fusion inhibitor moiety. Collectively, we present a novel HIV-1 inhibitor with a dual mode of action and excellent antiviral potency against wildtype and entry-inhibitor resistant virus strains suggesting that CD4-BFFI may have a high barrier to resistance.

Photodynamic therapy with topical methyl aminolaevulinate for 'difficult-to-treat' basal cell carcinoma

BACKGROUND

Basal cell carcinoma (BCC) may be difficult to treat by conventional means, particularly if the lesions are large or located in the mid-face (H-zone). Photodynamic therapy (PDT) using topical methyl aminolaevulinate (MAL) may be a good noninvasive option for these patients.

OBJECTIVES

To investigate the efficacy and safety of PDT using MAL for BCCs defined as 'difficult to treat', i.e. large lesions, in the H-zone, or in patients at high risk of surgical complications.

METHODS

This was a prospective, multicentre, noncomparative study. Patients were assessed 3, 12 and 24 months after the last PDT treatment. One hundred and two patients with 'difficult-to-treat' BCC were treated with MAL PDT, using 160 mg g(-1) cream and 75 J cm(-2) red light (570-670 nm), after lesion preparation and 3 h of cream exposure. Results Ninety-five patients with 148 lesions were included in the per protocol analysis. The histologically confirmed lesion complete response rate at 3 months was 89% (131 of 148). At 12 months, 10 lesions had reappeared, and therefore the cumulative treatment failure rate was 18% (27 of 148). At 24 months, an additional nine lesions had reappeared, resulting in a cumulative treatment failure rate of 24% (36 of 148). The estimated sustained lesion complete response rate (assessed using a time-to-event approach) was 90% at 3 months, 84% at 12 months and 78% at 24 months. Overall cosmetic outcome was judged as excellent or good in 79% and 84% of the patients at 12 and 24 months, respectively. Follow-up is continuing for up to 5 years.

CONCLUSIONS

MAL PDT is an attractive option for 'difficult-to-treat' BCC. Because of the excellent cosmetic results, the treatment is particularly well suited for lesions that would otherwise require extensive surgical procedures.

[Dacryolithiasis: diagnosis using nasal endoscopy]

PURPOSE

The purpose of this study was to assess the value of two new clinical findings for the diagnosis of dacryolithiasis discovered with nasal endoscopy: anatomical abnormalities of the Hasner valve (HV) and mucopurulent discharge visible at this valve. The value of these findings is compared with other clinical and radiological signs of dacryolithiasis. A hypothesis is developed as to the responsibility of the HV in the formation of dacryolithiasis.

METHOD

This study was prospective and based on 797 operations performed for epiphora: 647 endonasal dacryocystorhinostomies and 150 meatotomies of the HV, with systematic preoperative nasal videoendoscopy. Ninety dacryocystographies (DCGs) and 129 lacrimal computed tomographies (LCT) were preoperatively performed.

RESULTS

Dacryoliths were found in 55 of 797 patients (6.9%). The HV could be examined in 48 patients in the lithiasis group and in 687 patients in the control group. Mucopurulent discharge was observed in 22 patients with lithiasis (45.8%) and in 40 patients (5.8%) (p<10(-6)) of the control group. Anatomical abnormalities of the HV were found in 40 patients with dacryolithiasis (83.3%) as compared to 82 patients ing the control group (11.4%) (p<10(-6)). In 13 patients, the VH was very small (<2 mm), in 12 patients it was very long (>15 mm), and in 15 patients both abnormalities were observed. Other clinical signs were young age (mean, 48.2 years vs 59.1% in the control group) (p<0.05), a history of acute noninfectious dacryocystic retention (38.2% vs 9.5%) (p<10(-5)), partial obstruction of the lacrimal pathway (LP) (61.8% vs 30.5%) (p<10(-5)). The 28 LCTs that were performed in subjects who had lithiasis made it possible to diagnose 19 cases of dacryolithiasis and confirmed abnormalities of the HV causing narrowing of the LP in 20.

CONCLUSION

Dacryolithiasis is frequent and often misdiagnosed. When dacryolithiasis is suspected, a nasal videoendoscopic exam must be done to seek HV abnormalities and mucopurulent discharge at this valve. This latter finding, i.e., the association of mucopurulent discharge with a patent lacrimal system, has high specificity. The finding of numerous anatomical abnormalities of the HV may be an indication that congenital malformation of the HV is the cause of many cases of lithiasis.

A comparison of photodynamic therapy using topical methyl aminolevulinate (Metvix) with single cycle cryotherapy in patients with actinic keratosis: a prospective, randomized study

BACKGROUND

Actinic keratosis (AK) is a very common condition, which has the potential of progressing to squamous cell carcinoma. The present study is a prospective, randomized study comparing the lesion response, cosmetic outcome, patient satisfaction and tolerability of a new treatment modality, photodynamic therapy (PDT), using topical methyl aminolevulinate (Metvix), with the most commonly used standard therapy for AK, cryotherapy.

METHODS

A total of 204 patients with clinically diagnosed AK were randomized to either cryotherapy or PDT. The PDT patients were further assigned to an active or placebo group in a random, double-blind manner. Cryotherapy was performed using liquid nitrogen spray in a single freeze-thaw cycle. PDT was performed using 160 mg/g methyl aminolevulinate cream or placebo, a 3-hour application time, red light (570-670 nm) and a total light dose of 75 J/cm(2). PDT was repeated after 7 days. Two sessions of PDT were undertaken, as a previous study had shown a single session had similar efficacy to cryotherapy. Lesion response was assessed clinically after 3 months (complete response or non-complete response).

RESULTS

The lesion response rate was 91% in the methyl aminolevulinate PDT group, 68% in the cryotherapy group and 30% in the placebo PDT group. Methyl aminolevulinate PDT was statistically significantly better than both cryotherapy and placebo PDT in terms of response rates and cosmetic outcome. Most patients preferred PDT to other treatments.

CONCLUSIONS

PDT with methyl aminolevulinate is an excellent treatment option, particularly for patients with widespread damage or AK lesions in cosmetically sensitive areas.

Quantification of sodium dodecyl sulfate in microliter-volume biochemical samples by visible light spectroscopy

A method for sodium dodecyl sulfate (SDS) quantitation in microliter-volume complex biochemical samples is described. The quantitation is based on the use of a dye, stains-all, the color of which changes from intense fuchsia to yellow upon addition of SDS. We show that this color change is gradual and proportional to the amount of SDS added to the stains-all solution, thus allowing its use to reliably quantitate SDS in biochemical samples by means of a visible light spectrophotometer. A large number of compounds widely used in biochemistry are herein shown not to interfere with the SDS measurement when they are present in the sample at usual biochemical concentrations. Furthermore, linearity between the color change and the amount of SDS present in the sample is never impaired when huge amounts of these compounds are also present, thus making this quantitation method highly reliable with use of a calibration curve. The method allows easy and reliable quantitation of microgram amounts of SDS in microliter-volume biochemical samples.

Controlling electrophoretic trapping of circular DNA by addition of starch preparations to agarose gels

Starch preparations were added to agarose gels to enhance the electrophoretic trapping of circular plasmid DNA. The critical voltages required to trap the open circular (OC) and the supercoiled (SC) forms of a 13.1-kbp plasmid were measured in gels composed of agarose and added starch preparations. Modified starch preparations reduced the critical voltage required to trap the OC form of the plasmid to approximately one-third of the control value (in 1% agarose gels). Amylose (a fraction of starch with a low amount of branching) also reduced the critical voltage to trap the OC form in a similar manner. The critical voltage to trap the SC form of the plasmid was not significantly reduced by the starch preparations. The capacity to trap OC DNA was increased by the addition of higher amounts of the starch preparations added to the gels. Field inversion gel etectrophoresis was used to characterize the length of the traps in the gels. The starch preparations and amylose increased the trap lengths approximately twofold. The increased trap length correlated with the decreased critical voltage required to trap the OC form of the 13.1-kbp plasmid.

ERM-Merlin and EBP50 protein families in plasma membrane organization and function

The ezrin-radixin-moesin (ERM) family of proteins have emerged as key regulatory molecules in linking F-actin to specific membrane proteins, especially in cell surface structures. Merlin, the product of the NF2 tumor suppressor gene, has sequence similarity to ERM proteins and binds to some of the same membrane proteins, but lacks a C-terminal F-actin binding site. In this review we discuss how ERM proteins and merlin are negatively regulated by an intramolecular association between their N- and C-terminal domains. Activation of at least ERM proteins can be accomplished by C-terminal phosphorylation in the presence of PIP2. We also discuss membrane proteins to which ERM and merlin bind, including those making an indirect linkage through the PDZ-containing adaptor molecules EBP50 and E3KARP. Finally, the function of these proteins in cortical structure, endocytic traffic, signal transduction, and growth control is discussed.

Hierarchy of merlin and ezrin N- and C-terminal domain interactions in homo- and heterotypic associations and their relationship to binding of scaffolding proteins EBP50 and E3KARP

The neurofibromatosis 2 tumor suppressor gene product merlin has strong sequence identity to the ezrin-radixin-moesin (ERM) family over its approximately 300-residue N-terminal domain. ERM proteins are membrane cytoskeletal linkers that are negatively regulated by an intramolecular association between domains known as NH(2)- and COOH-ERM association domains (N- and C-ERMADs) that mask sites for binding membrane-associated proteins, such as EBP50 and E3KARP, and F-actin. Here we show that merlin has self-association regions analogous to the N- and C-ERMADs. Moreover, the N-/C-ERMAD interaction in merlin is relatively weak and dynamic, and this property is reflected by the ability of full-length recombinant merlin to form homo-oligomers. Remarkably, the merlin C-ERMAD has a higher affinity for the N-ERMAD of ezrin than the N-ERMAD of merlin. Both the ezrin and merlin N-ERMAD bind EBP50. This interaction with the ezrin N-ERMAD can be inhibited by the presence of the ezrin C-ERMAD, whereas interaction with the merlin N-ERMAD is not inhibited by either C-ERMAD. E3KARP binds tightly to the ezrin N-ERMAD but has little affinity for the merlin N-ERMAD. The implications of these associations and the hierarchies of binding for the function and regulation of merlin and ERM proteins are discussed.

Dynamic combinatorial chemistry

Dynamic combinatorial chemistry is based on the reversible combination of initial building blocks to form dynamic combinatorial libraries. It has recently emerged as an efficient strategy to detect and to evaluate affinity between the library products and a target molecule. In this review, examples from various fields of chemistry and biochemistry are presented and extensively discussed. The last section deals with the practical aspects for implementing this approach.

Gahat: a Napalese cure for urolithiasis?

OBJECTIVES

Gahat (Vigna unguiculata) is a legume used for centuries in Nepal and Pakistan to treat the symptoms associated with urinary calculi. We prospectively evaluated the effect of Gahat consumption on 24-hour urine parameters in an attempt to assess its in vivo effect in normal volunteers.

METHODS

Eight non-stone-forming volunteers collected 24-hour urine specimens while on their routine diets for baseline data. Urine was analyzed for pH, volume, calcium, citrate, phosphate, sodium, magnesium, uric acid, and oxalate. The Gahat was prepared according to local custom. No additives were used to enhance flavor. The pureed mixture (8 ounces) was ingested three times daily for 2 days. Subjects were instructed to maintain their normal diet, including fluid intake and activity during the study period. Twenty-four hours after the start of Gahat intake, a second 24-hour urine collection was initiated while volunteers continued the Gahat. Results of the urine samples before and after Gahat intake were analyzed, using the paired Student t test.

RESULTS

There were no significant differences in urinary electrolytes between the urine samples before and after Gahat intake. Magnesium, urine volume, and uric acid differences approached clinical significance.

CONCLUSIONS

Gahat increased urinary magnesium through an unknown mechanism and had no effect on other routine 24-hour urine electrolytes. The increase in urinary volume is attributed to the increase in fluid consumption by the subjects. If this legume is effective in preventing or dissolving urinary calculi, it may act through mechanisms not identified in 24-hour urine electrolytes.

Endoscopic thoracic sympathectomy for treatment of essential hyperhidrosis syndrome: experience with 650 patients

Patients with essential hyperhidrosis (EH) syndrome may experience subjective suffering and social/occupational challenges. We examined the safety and efficacy of minimally invasive endoscopic surgery for treating EH. Single bilateral incisions, followed by endoscopic thoracic sympathectomy (ETS)-mediated bilateral ablation of the T2 sympathetic ganglia, were used to treat 650 patients with a primary diagnosis of palmar (90%) or facial hyperhidrosis (10%). Palmar and facial hyperhidrosis were resolved in 584 of 585 (>99%) and 62 of 65 (95%) patients, respectively. Surgery required less than 1 hour, and no patient experienced a life-threatening adverse event. Compensatory sweating was observed in 83% of patients and was considered mild or moderate in approximately 67% of those patients. Innovations in ETS have resulted in minimally invasive, highly efficient, safe treatment of EH. Surgery is minimally intrusive to patients, who were usually discharged within 2 hours after surgery and able to resume normal activities within 1 week.