Real-World Apremilast Use for Treatment of Plaque Psoriasis in Italy: Patient Perspective, Characteristics, and Clinical Outcomes from the DARWIN Study

INTRODUCTION

While several European studies have reported real-world apremilast use, patient-perceived benefits, and treatment satisfaction, local reimbursement criteria for apremilast vary and data from Italy are limited.

METHODS

The cross-sectional DARWIN study enrolled consecutive patients who had initiated apremilast for plaque psoriasis 6 (± 1) months prior to enrolment at a single visit across 24 Italian dermatological sites. Disease severity was assessed using body surface area (BSA) and Physician Global Assessment (PGA). Patient-reported outcomes assessed 6 (± 1) months after apremilast initiation were Dermatology Life Quality Index (DLQI), Patient Benefit Index (PBI), and 9-item Treatment Satisfaction Questionnaire for Medication (TSQM-9).

RESULTS

Of 184 patients enrolled between July 2019 and January 2021, 180 were included in the analysis. At apremilast initiation, median (25th-75th percentile) time since psoriasis diagnosis was 8.6 (3.2-22.2) years; median BSA, 10.0% (5.0-16.0); mean (standard seviation, SD) DLQI total score, 13.5 (8.0). Over half (54.9%) of patients with available data reported psoriasis had a very or extremely large effect on their quality of life (QoL); half reported itching (50.6%) and/or special areas involvement (50.0%). Most (73.9%) had comorbidities and were biologic-naïve (81.5%). The most common reasons for initiating apremilast were lack of efficacy of previous treatment (56.7%) and contraindications to other treatments (44.4%). At 6 (± 1) months, most patients were continuing apremilast and/or reported a Global PBI score ≥ 1 (minimum clinical benefit) (86.1% and 90.0%, respectively); approximately half achieved BSA ≤ 3% and/or DLQI total score ≤ 5 (47.1% and 48.5%); 18.8% achieved PGA = 0; mean (SD) TSQM-9 global treatment satisfaction score was 59.0 (24.8). Apremilast was well tolerated; no new safety signals were identified.

CONCLUSIONS

Patients treated with apremilast for 6 months in Italian clinical practice reported improved QoL, clinically relevant improvements in symptoms, high treatment satisfaction, and high treatment persistence. Our data indicate apremilast is a valuable treatment option for moderate plaque psoriasis.

STUDY REGISTRATION

ClinicalTrials.gov identifier, NCT04031027.

Long-term proactive management of psoriasis with calcipotriol and betamethasone dipropionate foam: an Italian consensus through a combined nominal group technique and Delphi approach

BACKGROUND

Although long-term management of psoriasis is paramount, this approach is challenging in clinical practice. In the recent PSO-LONG trial, a fixed-dose combination of betamethasone dipropionate (BD) and calcipotriol (Cal) foam applied twice a week on non-consecutive days for 52 weeks (proactive treatment) reduced the risk of relapse. However, the role of Cal/BD foam in the long-term management of psoriasis needs further clarifications. The ProActive Management (PAM) program, a nationwide Italian project, aims at reaching a consensus on the role of proactive management of psoriasis.

METHODS

A steering committee generated some statements through the nominal group technique (NGT). The statements were voted by an expert panel in an adapted Delphi voting process.

RESULTS

Eighteen statements were proposed, and the majority of them (14/18) reached a consensus during the Delphi voting. The need to provide long-term proactive topical treatment to reduce the risk of relapse for the treatment of challenging diseases sites or in patients where phototherapy or systemic therapies are contraindicated/ineffective was widely recognized. A consensus was reached about the possibility to associate the proactive treatment with systemic and biological therapies, without the need for dose intensification, thus favoring a prolonged remission. Moreover, the proactive treatment was recognized as more effective than weekend therapy in increasing time free from relapses. Approaches to improve adherence, on the other hand, need further investigation.

CONCLUSIONS

The inclusion in guidelines of a proactive strategy among the effective treatment options will be a fundamental step in the evolution of a mild-moderate psoriasis therapeutic approach.

Tildrakizumab for treatment of moderate to severe psoriasis: an expert opinion of efficacy, safety, and use in special populations

INTRODUCTION

Tildrakizumab is a monoclonal antibody that targets the p19 subunit of IL-23, a crucial cytokine for Th17 cells. Tildrakizumab has been assessed in several Phase I, II, and III clinical trials and is approved for treatment of adults with moderate to severe plaque psoriasis who are indicated for systemic therapy.

AREAS COVERED

The available evidence on the efficacy, safety, and use of tildrakizumab in special populations was evaluated by 14 experts who critically reviewed the current literature.

EXPERT OPINION

Tildrakizumab has good efficacy that lasts for at least 5 years in patients with moderate to severe psoriasis, and appears to be safe and well tolerated in the long-term with no apparent dose-related differences in adverse events, a low incidence of discontinuation due to adverse events, and no evidence of increased risk of malignancies. The safety and the efficacy of tildrakizumab has also been confirmed in special populations such as those with inflammatory bowel disease, cardiovascular disease, metabolic syndrome, and advanced age. Early intervention with IL-23-inhibitors, such as tildrakizumab, may help to control symptoms and change the long-term course of the disease in patients affected by plaque psoriasis, while improving the quality of life and potentially minimizing the risk of developing comorbidities.

Patient satisfaction with calcipotriol/betamethasone dipropionate cutaneous foam for the treatment of plaque psoriasis: The LION real-life multicenter prospective observational cohort study

Topical treatment is the mainstay for mild or moderate psoriasis, but patients are generally little satisfied. Calcipotriol/betamethasone dipropionate (Cal/BD) cutaneous foam has shown to improve signs and symptoms in plaque psoriasis patients. This study assessed patient's satisfaction with Cal/BD foam in a real‐life Italian dermatological clinical practice. A multicenter, 4‐week observational prospective cohort study enrolled, in 17 Italian dermatology clinics, adult patients with plaque psoriasis on the body and/or scalp. Treatment satisfaction was assessed by 9‐item Treatment Satisfaction Questionnaire for Medication (TSQM‐9), preference over previous treatments by Patient Preference Questionnaire (PPQ), and change in disease state by Psoriasis Area Severity Index (PASI). Overall 256 patients were eligible, with a mean (SD) age of 55.6 (15.4) years, 59.4% were males. Psoriasis severity was mild in 52.0% of patients, moderate in 43.3%, and severe in 4.7%. Scalp involvement was present in 36.7% of patients. Previous antipsoriatic treatments had been received by 80.5% of patients. TSQM‐9 median (25th–75th percentile) scores were 83.3 (66.7–88.9) for effectiveness, 77.8 (66.7–88.9) for convenience, and 78.6 (64.3–92.9) for global satisfaction. Mean (SD) PASI value decreased from 7.3 (4.8) to 2.1 (2.7) after 4 weeks. More than 90% of patients previously treated for psoriasis evaluated the Cal/BD foam more effective, easier to use and better tolerated compared to previous topical treatments at PPQ. This observational study provides real‐life evidence of a high level of satisfaction with effectiveness and convenience of the Cal/BD foam in a cohort of plaque psoriasis patients, with an objective improvement in PASI.

Brodalumab for the treatment of moderate-to-severe plaque-type psoriasis: a real-life, retrospective 24-week experience

BACKGROUND

Brodalumab was efficacious and safe in moderate-to-severe plaque-type psoriasis in the AMAGINE trials; published reports under real-life conditions are limited.

OBJECTIVES

To evaluate the effectiveness and safety of brodalumab in patients with moderate-to-severe plaque-type psoriasis in a real-world setting.

METHODS

This observational, retrospective study enrolled adult patients (≥18 years) with moderate-to-severe plaque-type psoriasis who underwent 24 weeks of treatment with brodalumab at 17 Italian dermatological centres. Baseline data included demographics, comorbidities, age of onset and duration of psoriasis and previous treatments. Psoriasis Area and Severity Index (PASI), Physician Global Assessment (PGA), static PGA of Genitalia, Dermatology Life Quality Index and patient satisfaction were assessed at weeks 0, 4, 12 and 24; adverse events were recorded.

RESULTS

Seventy-eight patients (mean age 47.9 years, 71.8% male, average disease duration 16.8 years) were enrolled. A rapid and significant reduction in mean PASI score was observed after 4 weeks of treatment, decreasing further at weeks 12 and 24 (all P < 0.0001 vs. baseline). A higher number of cardiometabolic comorbidities and previous therapies were negatively associated with the achievement of PASI 90 at all assessments. Brodalumab was effective in bio-experienced patients, including those who had failed on anti-interleukin (IL)-17 therapies. Quality of life and patient satisfaction increased significantly during treatment (P < 0.0001 and P < 0.01 vs. baseline, respectively). Treatment was interrupted in 9 (11.5%) patients due to adverse events (n = 4), lack of efficacy (n = 3), lost to follow-up (n = 1) and surgical procedure (n = 1).

CONCLUSIONS

Brodalumab is effective and safe in the treatment of moderate-to-severe psoriasis in a real-world setting, including in patients with failure to anti-IL17 therapies.

Assessing the Beneficial Impact of a Patient Support Program in Secukinumab-Treated Patients with Psoriasis in Italy

PURPOSE

For patients with psoriasis, treatment adherence and persistence are fundamental if therapeutic goals are to be met. Patient Support Programs (PSPs) may be used as a support tool to assist patients and health care professionals optimize treatment and improve disease management.

PATIENTS AND METHODS

In Italy, the PSP PSOLife CARE, which began on the 9th of February 2017 and is ongoing, aimed to support patients with psoriasis under therapy with secukinumab (Cosentyx^®). A team of medical professionals including Dermatologists, Psychologists, Nutritionists, and field Nurses provided outpatient treatment as well as remote support via phone calls. Patients had a standard duration in the Program of 6 months. This report analyzes the data of patients who benefited from the Program from February 2017 to August 2020, for a total observation of 42 months.

RESULTS

We provide here a descriptive report on the benefits of participation in the PSOLife CARE Program for patients with psoriasis and medical professionals involved in their care. Throughout their time in the PSOLife CARE Program, patient satisfaction remained consistently high with sustained improvements observed in all aspects of quality of life (ie emotional, social, physical, and economic). Despite exiting from the Program, most patients continued to adhere to secukinumab. Medical professionals also reported positive outcomes on their interactions with patients, with more than half of those surveyed rating the overall quality of the Program as "Outstanding".

CONCLUSION

By supporting treatment adherence, the PSOLife CARE Program may have empowered patients to better manage their psoriasis, increasing their satisfaction with treatment and quality of life.

Effectiveness of cyclosporine A in patients with moderate to severe plaque psoriasis in a real-life clinical setting in Italy: the TRANSITION study

Background: Cyclosporine A (CsA) is one of the systemic therapeutic options for moderate-to-severe psoriasis, based on its efficacy and rapidity of action. The current study investigated the response to CsA in patients with moderate-to-severe plaque psoriasis.Materials and Methods: TRANSITION was an observational, cross-sectional, multicentre study which evaluated the proportion of partial- and suboptimal-responders among patients with moderate-to-severe plaque psoriasis treated with continuous CsA for ≥12 weeks. Patients demonstrating a Psoriasis Area and Severity Index (PASI) response of ≥90, ≥75 and <90, ≥50 and <75 and <50 were defined as responders, suboptimal-responders, partial-responders, and non-responders, respectively.Results: A total of 196 patients (mean age, 46.6 years; 62.8% males) from 14 sites in Italy were evaluated. At the study visit, the mean (SD) PASI score was 4.2(5.5) compared with 15.3(7.1) prior to the last CsA cycle. For response categories, 39.8%, 22.4%, 16.8%, and 20.9% of patients were responders, suboptimal-responders, partial-responders, and non-responders to CsA treatment. Overall, 28.6% of patients permanently discontinued treatment with CsA (lack of efficacy [10.2%], poor tolerability and voluntary discontinuation [3.6% each], and other [11.7%]).Conclusion: Patients were only partially satisfied with CsA treatment, reporting measurable impact on quality of life. Only 40% patients showed a satisfactory response to CsA.

Secukinumab for Psoriasis in Obese Patients: Minireview and Clinical Experience

Psoriasis (PsO) has been associated with obesity, and its severity increases in obese subjects. The link between psoriatic condition and obesity is based on shared pathophysiological pathways where local and systemic inflammation promote each other; PsO is an inflammatory, immune-mediated disease, and the adipose tissue is the source of proinflammatory adipokines. Moreover, psoriatic arthritis (PsA) is an important comorbidity of PsO that reduces quality of life and makes difficult the patient's management. Treatment of obese subjects with moderate to severe PsO, even more if PsA is present, is challenging because of reduced efficacy of several systemic drugs and increased risk of adverse events. Secukinumab, a monoclonal antibody that selectively binds to and neutralizes interleukin 17A, shows efficacy on PsO in all body weight groups, even in the highest, whose response has a slight downward trend. Clinical features of two obese subjects, affected by PsO and PsA, successfully treated with secukinumab, are described.

Wide local excision vs. Mohs Tübingen technique in the treatment of dermatofibrosarcoma protuberans: a two-centre retrospective study and literature review

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a rare, low-grade mesenchymal skin tumour, characterized by slow infiltrative growth and common local recurrence, with infrequent distant metastases.

OBJECTIVE

The aim of this study is to better clarify clinicopathological characteristics of this tumour and to evaluate the cure rates of Mohs Tübingen technique (MTT) and wide local excision (WLE). Eventually, we perform a literature review to compare our experience with published data.

METHODS

A retrospective review was conducted on 135 patients diagnosed, treated and followed up between 1997 and 2014 at two different institutions. Sixty-two patients underwent to WLE and 73 to MTT. The primary end-points were the following: percentage of recurrences, time to progression and recurrence annual risk rate. Then, the PubMed database was searched for DFSP case series treated with standard surgical resection (SSR), WLE, Mohs' micrographic surgery (MMS) and MTT. The annual risk rate of recurrence calculated and reported for the four separate procedures was pooled to compare them.

RESULTS

Five of the 62 patients with WLE (8.1%) experienced recurrences after a mean follow-up of 4.7 years; the percentage of recurred patients 9 years after MTT was 5.5%, and the annual recurrence risk rate of 0.6%. Pooling these data with those from literature, the recurrence rate varies from 26% to 60% for SSR, from 0% and 41% for WLE, from 0% and 8.3% for MMS and from 0% to 5.5% for MTT. The lowest annual recurrence risk rate was found for MTT.

CONCLUSION

Significantly lower recurrence rates were recorded in patients treated with classic or Tübingen Mohs' technique. To the best of our knowledge, our case series is the widest treated with MTT ever described in the literature; these data may be useful to guide clinicians in the choice of the gold standard treatment for Dermatofibrosarcoma protuberans.

Extemporaneous transposition flap for closing two contiguous surgical excision

The authors present a surgical procedure to remove two contiguous cutaneous lesions using a single transposition flap and suture line without an evident scar. This method is useful when rhomboid surgical exeresis could not represent the best choice to obtain an optimum aesthetic result.

Basal Cell Carcinoma of the Nipple in a Male Patient: A Particular Case Report

Basal cell carcinoma (BCC) is a common skin cancer worldwide. However, BCC of the nipple and areola complex is rare. Men are more affected than women. Most of the cases were treated with simple excision. We report a case of BCC of the right nipple-areola complex in a 75-year-old man, treated with Mohs surgery and simple mastectomy.

Clinical series of patients with cutaneous melanoma followed-up at the Novara Melanoma Centre from 1983 to 2009: description of the cohort and prognostic factors

AIM

The aim of this study was to review our experience with regards to patients with cutaneous melanoma diagnosed from 1983 to 2009, followed-up in our Dermatological Department of Novara.

METHODS

A retrospective study of 762 patients diagnosed with cutaneous melanoma in the Dermatological Department of Novara between 1983 and 2009 was conducted. Information was extracted from our melanoma patient database. The database included demographical, clinical and pathological variables of the patient. Clinical and pathological factors predicting survival were analyzed using the Kaplan-Meier curves and the Log-Rank Test (univariate analysis).

RESULTS

Staging (American Joint Committee on Cancer 2001) of patients (P=0.000), Breslow thickness (P=0.000), primary ulceration and regression of the lesion (P=0.000), type of first (P<0.039) and second recurrence (P<0.011) were strongly correlated with overall and disease free survival. Sentinel lymph node biopsy was not correlated with disease free survival (P=0.153), it influences only overall survival (P=0.007) CONCLUSION: Our results confirms that sentinel node biopsy, Breslow thickness, ulceration, regression, staging, first and second recurrence are important variable for overall survival and disease free survival, sentinel lymph node status influence only overall survival instead.

Selective release of cytokines, chemokines, and growth factors by minced skin in vitro supports the effectiveness of autologous minced micrografts technique for chronic ulcer repair

A new effective surgical procedure to repair chronic ulcers called minced micrografts technique has been recently reported. The technique consists in spreading a finely minced skin sample upon the wound bed. In this study, we investigate the in vitro release of cytokines (interleukin-6, tumor necrosis factor-α, interleukin-1α, and granulocyte-colony stimulating factor), chemokines (monocyte chemoattractant protein-1 and growth-related oncogene-α), and growth factors (platelet-derived growth factor, basic fibroblast growth factor, vascular endothelial growth factor, hepatocyte growth factor, and nerve growth factor) by minced (referred to as the minced sample) vs. not minced (referred to as the whole sample) human skin biopsy samples from the same donor. Factor release in the culture medium at different time points was detected using a multiplexed protein assay. The minced sample, which could behave like the skin fragments used in vivo in the autologous minced micrografts technique, expressed higher levels of tumor necrosis factor-α, interleukin-1α, platelet-derived growth factor, and basic fibroblast growth factor, and lower levels of interleukin-6, monocyte chemoattractant protein-1, growth related oncogene-α, and vascular endothelial growth factor compared with the whole sample. In conclusion, mincing of healthy skin may allow appropriate regulation of the inflammatory phase of wound healing and could induce overexpression of some growth factors, which facilitates the proliferative phase of healing.

Pigmented basal cell carcinomas in Gorlin syndrome: two cases with different dermatoscopic patterns

We describe two nonconsanguineous white patients with multiple pigmented basal cell carcinomas (BCCs) that were histopathologically confirmed. The first patient had calcification of the cerebral falx, multiple keratocysts in the jaw, and other malformations of the cranial and finger bones. The second patient presented with multiple dermoid cysts, calcification of the cerebral falx, keratocysts of the mandible, and agenesis of left kidney. Both patients had palmar pits. Both denied any family history of cutaneous tumours. On dermatoscopic examination of patient 1, multiple, bluish, confluent and large globules were seen. The second patient had blue ovoid globules, arborizing vessels, and areas shaped like maple leaves and spoke-wheels. Based on the clinical and radiological features we diagnosed both patients as having Gorlin syndrome (GS). To our knowledge, there are no previous reports of white patients with GS showing only pigmented BCCs. The dermatoscopic patterns were different in the two patients, and to our knowledge, this is the first report of a patient with GS showing a spoked-wheel dermatoscopic pattern.

[Dermatofibrosarcoma protuberans: surgical treatment using the Tübingen technique (31 cases)]

BACKGROUND

Dermatofibrosarcoma protuberans is a rare cutaneous sarcoma that progresses slowly. Although it exhibits pronounced local aggressiveness, it rarely metastasises. The condition is difficult to treat on account of asymmetric and unpredictable growth as well as the frequency of relapse. Treatment is primarily surgical.

PATIENTS AND METHODS

We report 31 cases of dermatofibrosarcoma protuberans operated at the Dermatology Clinic of Novara between 1997 and 2004 using the Tübingen technique. An immunohistochimical study was performed and screening was carried out for possible extension of the neoplasm into muscle.

RESULTS

Muscular involvement was seen in 4 cases. No relapses were seen over a median survival period of 3 years and no patients were lost to follow-up.

DISCUSSION

The Mohs technique is the surgical method of reference and allows tumour eradication with sparing of healthy tissue. The Tübingen method constitutes an alternative approach requiring fewer histological sections. The results obtained in our series were good and no relapses were seen over a median survival period of 3 years.

Activation of caspase-8 triggers anoikis in human neuroblastoma cells

Cells require appropriate interaction with extracellular matrix proteins mediated by integrins to grow, differentiate and survive. Many cell types including nervous cells undergo anoikis, a substrate-dependent apoptosis, when adhesion is impaired. Resistance of tumors to cytotoxic drugs is probably due to disturbed apoptosis programs. The proteolytic enzymes caspases are the main executioners of apoptosis. It was reported that caspase-8 expression is deficient in some neuroblastoma cells. We demonstrated that human neuroblastoma cell line SK-B-BE, differentiated with retinoic acid, expressed caspases 3, 8 and 9. Caspases 8 and 3, but not caspase-9 were activated in SK-N-BE cells cultured in suspension or on aspecific adhesive substrate. Cell positive to caspase-8 were classified into four stages, by morphometric and densitometric parameters. The use of the specific caspase-8 inhibitor Z-IETD-FMK dramatically reduced apoptosis, demonstrating that caspase-8 is the upstream initiator caspase during SK-N-BE cells anoikis. Among matrix proteins, type I collagen is the most effective and fibronectin the least in delaying anoikis. The activation of caspases 8 and 3 by unligated integrins was dependent on the state of neuronal differentiation, since the most differentiated cell was the most vulnerable to anoikis. These data show that activation of caspase-8 is specifically required to promote anoikis in SK-N-BE neuroblastoma cells.

Thysanoptera dermatitis

Thysanoptera dermatitis is caused by the bite of small (1-2 mm) insects (generally thrips). Thrips usually feed on the juices of vegetables but if they reach human skin they can suck the epidermal lymph after biting. The cutaneous lesions formed are small pink and itchy papules localized mainly on the trunk and the arms. Diagnosis is only possible by demonstrating that the insect is present inside one of the lesions of the skin. Thysanoptera dermatitis is often misdiagnosed as mosquito bites. Although self-resolving in a few days, Thysanoptera dermatitis should be known not only for the cultural and scientific training of the dermatologist but also to add more detailed diagnostic information to the generic diagnosis of 'entomodermatosis' and to confirm the benign evolution of the bites.

Extension cutanée d’un chordome

INTRODUCTION

Chordomas are rare extradural bone tumors arising from notochord remnants, the embryonic structure forming the original axis of the spine. They represent 0.1p. 100 of all intra-cranial tumors. The chordoma is a locally malignant cancer that tends to invade the surrounding tissues. Its localization in the skin is exceptional.

OBSERVATION

A 56 year-old man developed a nut-sized vegetating nodule on the nasal groove. This lesion appeared a few months following surgery for a frontoglabellar relapse of a chordoma that had developed six years earlier at the base of the skull.

DISCUSSION

We report this case because of the rareness of cutaneous involvement and the particular conditions in which it occurred. It may have been due to tumoral seeding during the previous surgical interventions.

FLICE/caspase-8 activation triggers anoikis induced by β1-integrin blockade in human keratinocytes

β1-integrin protects keratinocyte stem cells (KSC) from cell-detachment apoptosis (`anoikis'). Here we show that caspase-8 active protein is detected in both young transit amplifying (TA) cells and TA cells, but not in KSC. On suspension, caspases are activated earlier in young TA than in KSC, whereas anti-β1-integrin neutralizing antibody accelerates caspase activation in both KSC and young TA. Caspases 8 and 10 are the first caspases to be activated whereas caspase-8 inhibitor zIETD-fmk delays the activation of Bid, caspase-9 and caspase-3. However, the caspase-9 inhibitor zLEDH-fmk does not block the activation of caspase-8, Bid, caspase-10 and caspase-3. Moreover, caspase-8, but not caspase-9 inhibitor partially prevents keratinocyte anoikis. As FLIP inhibits caspase-8 processing, we retrovirally infected HaCaT keratinocytes with c-FLIPL. Anti-β1-integrin fails to activate caspase-8, Bid, caspase-9 and to induce the release of cytochrome c in c-FLIPL overexpressing keratinocytes. Finally, overexpression of c-FLIPL partially prevents anoikis in both suspended and anti-β1 integrin-treated cells. Taken together, these results indicate that the extrinsic apoptotic pathway triggered by caspase-8 predominates in keratinocyte anoikis. However, the release of cytochrome c and the later activation of caspase-9 seem to suggest that the intrinsic mitochondrial pathway may intervene as a positive feedback loop of caspase activation.

Keratinocytes enriched for stem cells are protected from anoikis via an integrin signaling pathway in a Bcl-2 dependent manner

Because inhibition of integrin signaling induces apoptosis, we investigated whether keratinocytes expressing beta1 and alpha6beta4 integrins (enriched for stem cells) are protected from cell death. Keratinocytes rapidly adhering to type IV collagen expressed highest levels of beta1 and alpha6beta4 and of the anti-apoptotic stem cell marker p63. Apoptotic cells were significantly higher in slowly adhering than in rapidly adhering keratinocytes. Anti-beta1 integrin caused a significant increase in apoptotic cells, while it decreased Bcl-2 levels in stem keratinocytes. Bax and Bad proteins were higher in slowly adhering than in rapidly adhering cells. By contrast, Bcl-2, Bcl-x and Mcl-1 proteins were highest in rapidly adhering keratinocytes and nearly absent in slowly adhering cells. After addition of anti-beta1 integrin, the apoptotic rate was significantly higher in HaCaT cells not expressing Bcl-2 than in controls. These results indicate that keratinocytes enriched for stem cells are protected from apoptosis via beta1 integrin, in a Bcl-2 dependent manner.

Image sharpness and contrast transfer in coherent confocal microscopy

Confocal microscopes provide clear, thin optical sections with little disturbance from regions of the specimen that are not in focus. In addition, they appear to provide somewhat greater lateral and axial image resolution than with non-confocal microscope optics. To address the question of resolution and contrast transfer of light microscopes, a new test slide that enables the direct measurement of the contrast transfer characteristics (CTC) of microscope optics at the highest numerical aperature has been developed. With this new test slide, the performance of a confocal scanning laser microscope operating in the confocal reflection mode and the non-confocal transmission mode was examined. The CTC curves show that the confocal instrument maintains exceptionally high contrast (up to twice that with non-confocal optics) as the dimension of the object approaches the diffraction limit of resolution; at these dimensions, image detail is lost with non-confocal microscopes owing to a progressive loss of image contrast. Furthermore, we have calculated theoretical CTC curves by modelling the confocal and non-confocal imaging modes using discrete Fourier analysis. The close agreement between the theoretical and experimental CTC curves supports the earlier prediction that the coherent confocal and the incoherent non-confocal imaging mode have the same limit of resolution (defined here as the inverse of the spatial frequency at which the contrast transfer converges to zero). The apparently greater image resolution of the coherent confocal optics is a consequence of the improved contrast transfer at spacings which are close to the resolution limit.

Biosynthesis of isochorismate in Klebsiella pneumoniae: origin of O-2

The shikimate metabolites are key precursors to a large number of natural products, including aromatic amino acids. Chorismic acid is an important branch point in the biosynthetic pathway to aromatic amino acids. Chorismic acid is also unique among natural products since it is the only compound known to undergo an enzymatic Claisen rearrangement. A metabolite of chorismic acid, isochorismic acid, first observed in Aerobacter aerogenes differs in its chemical structure by the location of the hydroxyl group and the double bonds. Isochorismic acid is a precursor to a growing number of shikimate-derived metabolites. Isochorismic acid has also been postulated to be an intermediate of m-carboxyaromatic amino acids, implying another enzymatic Claisen rearrangement. In this publication, we have isolated isochorismate synthase and found that on lyophilization the enzyme is stable for at least 6 months at -20 degrees C. Incubation of chorismate with this preparation in water enriched with 18O led to incorporation of one atom of 18O as proven from the fast atom bombardment mass spectra of the HPLC purified derived isochorismate.

Structure of D-prephenyllactate. A carboxycyclohexadienyl metabolite from Neurospora crassa

A novel natural product structurally related to prephenate and arogenate was isolated from a mutant of Neurospora crassa. This D-beta-(1-carboxy-4-hydroxy-2,5-cyclohexadiene-1-yl)-lactic acid is herein given the trivial name of D-prephenyllactate. The new metabolite is even more acid labile than is prephenate and is quantitatively converted to phenyllactate at mildly acidic pH. The structure characterization of prephenyllactate was performed using spectroscopic techniques (ultraviolet, 1H NMR, 13C NMR, two-dimensional heteronuclear experiments and mass spectrometry). Circular dichroism proved conclusively the R configuration of the asymmetric carbon at C-8 of prephenyllactate. Enzymatic utilization of prephenyllactate by cyclohexadienyl dehydratase and by cyclohexadienyl dehydrogenase from Klebsiella pneumoniae was demonstrated.