Trimers Conjugated to Fibrin Hydrogels Promote Salivary Gland Function

New strategies for tissue engineering have great potential for restoring and revitalizing impaired tissues and organs, including the use of smart hydrogels that can be modified to enhance organization and functionality of the salivary glands. For instance, monomers of laminin-111 peptides chemically conjugated to fibrin hydrogel (L_1pM-FH) promote cell cluster formation in vitro and salivary gland regeneration in vivo when compared with fibrin hydrogel (FH) alone; however, L_1pM-FH produce only weak expression of acinar differentiation markers in vivo (e.g., aquaporin-5 and transmembrane protein 16). Since previous studies demonstrated that a greater impact can be achieved when trimeric forms were used as compared with monomeric or dimeric forms, we investigated the extent to which trimers of laminin-111 chemically conjugated to FH (L_1pT-FH) can increase the expression of acinar differentiation markers and elevate saliva secretion. In vitro studies using Par-C10 acinar cells demonstrated that when compared with L_1pM-FH, L_1pT-FH induced similar levels of acinar-like cell clustering, polarization, lumen formation, and calcium signaling. To assess the performance of the trimeric complex in vivo, we compared the ability of L_1pM-FH and L_1pT-FH to increase acinar differentiation markers and restore saliva flow rate in a salivary gland wound model of C57BL/6 mice. Our results show that L_1pT-FH applied to wounded mice significantly improved the expression of the acinar differentiation markers and saliva secretion when compared with the monomeric form. Together, these positive effects of L_1pT-FH warrant its future testing in additional models of hyposalivation with the ultimate goal of applying this technology in humans.

Three cases of digital ischemia successfully treated with cilostazol

Three patients were evaluated for refractory digital ischemia. The first patient presented with chronic, post-traumatic, unremitting, cold, painful, right fourth and fifth fingers. The symptoms had failed to improve despite topical nitroglycerin and a calcium channel blocker. Baseline digital plethysmography documented impaired perfusion within the affected digits. Cilostazol (Pletal) was added to the medical regimen and at the 8-week follow-up the fourth and fifth fingers were warm with repeat plethysmography displaying normal perfusion. A second patient had CREST syndrome-associated painful bilateral index finger ulcerations that had evolved despite taking a calcium channel blocker. Consequently the patient was started on cilostazol and within 4 weeks the digital ulcerations and pain had resolved. The third patient with traumatic right fifth digital arterial thrombosis was seen for persistent pain and cyanosis in spite of undergoing thrombolysis and subsequent anticoagulation with vasodilator therapy. Digital plethysmography established fixed ischemia within the fifth finger; subsequently, cilostazol was prescribed. Four weeks later the digital pain and cyanosis had essentially resolved. A follow-up plethysmographic waveform documented restored perfusion. Although approved for the treatment of intermittent claudication, cilostazol was successfully utilized in the setting of severe digital ischemia.

Phenanthrene degradation in soils co-inoculated with phenanthrene-degrading and biosurfactant-producing bacteria

Contaminant sorption within the soil matrix frequently limits biodegradation. However, contaminant bioavailability can be species-specific. This study investigated bioavailability of phenanthrene (PHE) to two PHE-degrading bacteria (Pseudomonas strain R and isolate P5-2) in the presence of rhamnolipid biosurfactant and/or a biosurfactant-producing bacterium, Pseudomonas aeruginosa ATCC 9027. Pseudomonas strain R mineralized more soil-sorbed PHE than strain P5-2, but in aqueous cultures the rate and extent of PHE mineralization by P5-2 exceeded that by P. strain R. In Fallsington sandy loam (fine-loamy, mixed, active, mesic Typic Endoaquult) (high PHE-sorption capacity) the addition of rhamnolipid increased PHE mineralization by P. strain R. Phenanthrene mineralization in soils inoculated with P5-2 was minimal and no enhancement in PHE degradation was observed when biosurfactant was added. Co-inoculation of Fallsington sandy loam with the biosurfactant producer did not affect PHE mineralization by isolate P5-2, but significantly enhanced PHE mineralization by P. strain R. The enhancement of PHE mineralization could not be explained by P. aeruginosa-mediated PHE degradation. The addition of rhamnolipid at concentrations above the critical micelle concentration (CMC) resulted in enhanced PHE release from test soils. These results suggest that the PHE-degrading strains were able to access different pools of PHE and that the biosurfactant-enhanced release of PHE from soils did not result in enhanced biodegradation. The results also demonstrated that bacteria with the catabolic potential to degrade sorbed hydrophobic contaminants could interact commensally with surfactant-producing strains by an unknown mechanism to hasten the biodegradation of aromatic hydrocarbons. Thus, understanding interactions among microbes may provide opportunities to further enhance biodegradation of soil-bound organic contaminants.

Calciphylaxis: a favorable outcome with hyperbaric oxygen

A 66-year-old female with diabetes mellitus and end-stage renal disease presented with painful bilateral lower extremity livedo reticularis and necrotic ulcerations. Her distal lower extremity pulses were intact and plethysmographic studies confirmed relatively normal large vessel arterial perfusion. Extensive laboratory analysis was remarkable for an elevated calcium x phosphorous product and parathyroid hormone level. An ulcer biopsy revealed small vessel medial calcinosis, and calciphylaxis was subsequently diagnosed. Despite aggressive wound debridements, antibiotics and subtotal parathyroidectomy, her ulcers failed to improve significantly prompting a trial of hyperbaric oxygen therapy. After 7 weeks of hyperbaric treatments, her ulcers had essentially healed.

Ultrasound-guided compression closure of postcatheterization pseudoaneurysms during concurrent anticoagulation: a review of seventy-seven patients

PURPOSE

Data from our institution and elsewhere have demonstrated that ultrasound-guided compression closure (UGCC) is an effective method of treating postcatheterization pseudoaneurysms. Whereas patients receiving anticoagulation do not have as high a success rate as those not receiving anticoagulants, there have been no large series evaluating the factors associated with success or failure in patients receiving anticoagulation. The purpose of this study is to determine whether uninterrupted anticoagulation interferes with successful UGCC of pseudoaneurysms and to identify factors associated with success or failure.

METHODS

From May 1991 to September 1994, 238 cases of attempted UGCC of pseudoaneurysms were performed in our vascular laboratory. Only patients who received uninterrupted heparin, warfarin, or both at the time of pseudoaneurysm compression were eligible for inclusion into the study. Seventy-seven patients were identified who met the study criteria.

RESULTS

Successful pseudoaneurysm compression was obtained in 56 (73%) patients, whereas 21 (27%) patients had a failed UGCC. In the successfully treated group, seven (12.5%) required between two to three compression attempts to induce sustained thrombosis. There was no statistical difference in age, sex, sheath size, days after procedure, location of pseudoaneurysm, or number of chambers in the pseudoaneurysm between those patients who had a successful repair and those who did not. If the pseudoaneurysm was less than 4 cm in diameter, 51 of 65 patients (78%) had a successful repair compared with 5 of 12 patients (42%) with a pseudoaneurysm of 4 cm or greater (p = 0.013). There was no statistical difference between success and failure in patients receiving warfarin alone (3.73 mean international normalized ratio, 72% success rate), heparin alone (mean activated partial thromboplastin time of 63 seconds, 92% success rate), or heparin and warfarin (mean activated partial thromboplastin time of 70 seconds, mean international normalized ratio of 4, success rate of 67%). No arterial or venous thrombosis occurred during pseudoaneurysm compression.

CONCLUSION

Successful UGCC of pseudoaneurysms occurred in a large percentage of patients receiving full-dose, uninterrupted anticoagulation. The only factor influencing success was the size of the pseudoaneurysm.

Flashlamp-excited dye laser therapy of idiopathic vulvodynia is safe and efficacious

OBJECTIVE

The management of chronic vulvovaginal pain, not explicable on specific histologic grounds, presents a major problem in referral centers for lower genital tract diseases.

STUDY DESIGN

This article reports on a two-step protocol in a sample of 175 medical nonresponders, drawn from a 2-year cohort of 725 women with vulvovaginal pain. The first maneuver was the use of a flashlamp-excited dye laser to selectively photocoagulate symptomatic subepithelial blood vessels in 168 women; the second was the microsurgical removal of chronically painful Bartholin's glands in 52 women not responsive or not suited to flashlamp-excited dye laser photothermolysis.

RESULTS

Dye laser response rates were independent of whether patients manifested macroscopic foci of painful erythema ("vestibular adenitis") or just colposcopically apparent hyperemia-ectasia of the individual blood vessels ("pruritic papillomatosis") (56% vs 45% after a single surgical procedure; 76% vs 65% after serial retreatment; p not significant). Conversely, response rates were much lower among women in whom pressure on the Bartholin's glands produced sharp, lancinating pain (15% vs 66% after a single surgical procedure; 22% vs 93% after serial retreatment; p < 0.001). Forty-two (85%) of 50 patients with flashlamp-excited dye laser failure had deep pain; however, the impasse to progress was broken by gland removal. Final response rates were 92.5% (complete response 62%; partial response 30%) in the "surface-only" group and 80.3% in the "surface-plus-deep" group (chi 2 = 14.9; p < 0.001). The major complication was acute bacterial cellulitis, occurring in the first postoperative week. Modification of the treatment protocol to include topical antibiotics with an occlusive dressing reduced the cellulitis rate from 17.2% to 2.5%. In four women (1.8%) Koebner-like exophytic condylomas also developed within 1 month of flashlamp-excited dye laser surgery.

CONCLUSION

The availability of a safe, efficacious, and relatively noninvasive treatment should reduce the need for resective surgery in most patients with idiopathic vulvodynia.