Genomic structure of an attenuated quasi species of HIV-1 from a blood transfusion donor and recipients

A blood donor infected with human immunodeficiency virus-type 1 (HIV-1) and a cohort of six blood or blood product recipients infected from this donor remain free of HIV-1-related disease with stable and normal CD4 lymphocyte counts 10 to 14 years after infection. HIV-1 sequences from either virus isolates or patient peripheral blood mononuclear cells had similar deletions in the nef gene and in the region of overlap of nef and the U3 region of the long terminal repeat (LTR). Full-length sequencing of one isolate genome and amplification of selected HIV-1 genome regions from other cohort members revealed no other abnormalities of obvious functional significance. These data show that survival after HIV infection can be determined by the HIV genome and support the importance of nef or the U3 region of the LTR in determining the pathogenicity of HIV-1.

Implantation of stimulated homologous macrophages results in partial recovery of paraplegic rats

Postinjury recovery in most tissues requires an effective dialog with macrophages; however, in the mammalian central nervous system, this dialog may be restricted (possibly due to its immune-privileged status), which probably contributes to its regeneration failure. We circumvented this by implanting macrophages, pre-exposed ex vivo to peripheral nerve segments, into transected rat spinal cord. This stimulated tissue repair and partial recovery of motor function, manifested behaviorally by movement of hind limbs, plantar placement of the paws and weight support, and electrophysiologically by cortically evoked hind-limb muscle response. We substantiated these findings immunohistochemically by demonstrating continuity of labeled nerve fibers across the transected site, and by tracing descending fibers distally to it by anterograde labeling. In recovered rats, retransection of the cord above the primary transection site led to loss of recovery, indicating the involvement of long descending spinal tracts. Injection of macrophages into the site of injury is relatively non-invasive and, as the cells are autologous, it may be developed into a clinical therapy.

Complementary signaling pathways regulate the unfolded protein response and are required for C. elegans development

The unfolded protein response (UPR) is a transcriptional and translational intracellular signaling pathway activated by the accumulation of unfolded proteins in the lumen of the endoplasmic reticulum (ER). We have used C. elegans as a genetic model system to dissect UPR signaling in a multicellular organism. C. elegans requires ire-1-mediated splicing of xbp-1 mRNA for UPR gene transcription and survival upon ER stress. In addition, ire-1/xbp-1 acts with pek-1, a protein kinase that mediates translation attenuation, in complementary pathways that are essential for worm development and survival. We propose that UPR transcriptional activation by ire-1 as well as translational attenuation by pek-1 maintain ER homeostasis. The results demonstrate that the UPR and ER homeostasis are essential for metazoan development.

Diabetes, Alzheimer disease, and vascular dementia: a population-based neuropathologic study

OBJECTIVE

To investigate the relation of diabetes to dementia, Alzheimer disease (AD), and vascular dementia (VaD), through analyses of incidence, mortality, and neuropathologic outcomes in a prospective population-based study of the oldest old.

METHODS

The Vantaa 85+ study included 553 residents living in the city of Vantaa, Finland, and aged ≥85 years on April 1, 1991. Survivors were reexamined in 1994, 1996, 1999, and 2001. Autopsies were performed in 291 persons who died during the follow-up (48% of total population). Diabetes was assessed according to self-report, medical record of physician-diagnosed diabetes, or use of antidiabetic medication. Macroscopic infarcts were identified from 1-cm coronal slices of cerebral hemispheres, 5-mm transverse brainstem slices, and sagittal cerebellum slices. Methenamine silver staining was used for β-amyloid, methenamine silver-Bodian staining for neurofibrillary tangles, and modified Bielschowsky method for neuritic plaques. Cox proportional hazards and multiple logistic regression models were used to analyze the association of diabetes with dementia and neuropathology, respectively.

RESULTS

Diabetes at baseline doubled the incidence of dementia, AD, and VaD, and increased mortality. Individuals with diabetes were less likely to have β-amyloid (hazard ratio [HR] [95% confidence interval (CI)] was 0.48 [0.23-0.98]) and tangles (HR [95% CI] 0.72 [0.39-1.33]) but more likely to have cerebral infarcts (HR [95% CI] 1.88 [1.06-3.34]) after all adjustments.

CONCLUSION

Elderly patients with diabetes develop more extensive vascular pathology, which alone or together with AD-type pathology (particularly in APOE ε4 carriers) results in increased dementia risk.

Consensus guidelines for the conduct and reporting of clinical trials in systemic light-chain amyloidosis

This manuscript summarizes the recommendations that emerged from the first Roundtable on Clinical Research in Immunoglobulin Light-chain Amyloidosis (AL), a meeting sponsored by the Amyloidosis Foundation (Clarkston, MI, USA) to develop a consensus of experts on a modern framework for clinical trial design and drug development in AL. Recent diagnostic and technical advances in AL, and updated consensus guidelines for assessing hematologic and organ responses, enable us to define study populations, appropriate end points, and other criteria for all phases of clinical research. This manuscript provides a framework for the design and conduct of systematic collaborative clinical research in AL to encourage more rapid testing of therapies and to expedite new drug development and approval.

The diagnosis and management of dry eye: a twenty-five-year review

PURPOSE

To review the advances in the diagnosis, pathogenesis, and management of dry eye disease in the past 25 years.

METHODS

Literature review.

RESULTS

The preocular tear film is a hydrated mucus gel that contains soluble antimicrobial proteins and growth factors that protect and support the ocular surface. The final common pathway in dry eye is a perturbation of the integrated ocular surface/lacrimal gland reflex unit. Diagnostic tests evaluating tear composition and clearance appear to show stronger correlation with the severity of ocular irritation symptoms and keratoconjunctivitis sicca (KCS) than the conventional Schirmer tests. KCS is a condition of abnormal differentiation and mucus production by the ocular surface epithelium that results in a poorly lubricated, abnormally permeable ocular surface that has increased susceptibility to environmental insults. Chronic subclinical ocular surface inflammation appears to play a key role in the pathogenesis of KCS. New therapeutic strategies are aimed at reducing the ocular surface inflammation of dry eye disease.

CONCLUSIONS

There has been a tremendous increase in knowledge regarding dry eye disease in the past 25 years that has resulted in improved diagnostic classification and new targeted therapies.

Nephrotoxic potential of Bence Jones proteins

BACKGROUND

The renal manifestations of diseases associated with the production of monoclonal light chains--myeloma (cast) nephropathy, light-chain deposition disease, and amyloidosis AL--result from the deposition of certain Bence Jones proteins as tubular casts, basement-membrane precipitates, or fibrils, respectively. For unknown reasons, the severity of the renal manifestations of these diseases varies greatly from patient to patient. We employed an experimental in vivo model to determine the pathologic importance of various Bence Jones proteins.

METHODS

Mice were injected intraperitoneally with 300 mg of Bence Jones protein from 40 patients with multiple myeloma or amyloidosis AL and killed 48 hours later. The mouse kidneys were examined by light and electron microscopy, and light-chain deposits were identified immunohistochemically with highly specific antihuman light-chain antiserum.

RESULTS

Of the 40 different human Bence Jones proteins studied, 26 were deposited in the mouse kidneys predominantly as tubular casts, basement-membrane precipitates, or crystals; no light-chain deposits were detected in the kidneys of the mice that received the other 14 Bence Jones proteins. Of the 18 patients for whom renal tissue was available for study, the findings in 14 were comparable to those in the mice. Furthermore, the proteins obtained from 22 of the 27 patients whose serum creatinine concentrations equaled or exceeded 168 mumol per liter (1.9 mg per deciliter) were deposited in the mouse kidneys, whereas protein deposition occurred after the injection of proteins from only 4 of the 13 patients with serum creatinine concentrations below 168 mumol per liter. The repeated injection of Bence Jones proteins from two patients who had amyloidosis AL resulted in deposition of the protein in the mouse kidneys as amyloid.

CONCLUSIONS

Particular Bence Jones proteins are primarily responsible for producing the distinctive types of protein deposition in renal tissue and the clinical manifestations that occur in patients with light-chain-associated diseases. This experimental model has potential value for the identification of nephrotoxic or amyloidogenic light chains.

Long-term outcome of keratolimbal allograft with or without penetrating keratoplasty for total limbal stem cell deficiency

PURPOSE

To evaluate the long-term outcome of ocular surface reconstruction, including keratolimbal allograft (KLAL) and amniotic membrane transplantation (AMT) with or without penetrating keratoplasty (PKP), in patients with nonambulatory vision secondary to total limbal stem cell deficiency (LSCD).

DESIGN

Retrospective, non-comparative interventional case series.

PARTICIPANTS

Thirty-nine eyes in 31 consecutive patients with total LSCD, as defined by impression cytology, who had a preoperative best-corrected visual acuity of less than 20/200 and a minimum follow-up of 12 months. Patients were divided into three groups: group 1 (16 eyes) with chemical burns, group 2 (9 eyes) with Stevens-Johnson syndrome (SJS), and group 3 (14 eyes) with other causes of LSCD, including ocular cicatricial pemphigoid, atopic keratoconjunctivitis, and aniridia.

INTERVENTION

All patients underwent KLAL and AMT by one surgeon (SCGT). If needed, PKP was performed at the same surgical setting using tissue from the same donor.

MAIN OUTCOME MEASURES

Cumulative rates of survival of ambulatory vision (> or = 20/200), survival of KLAL, survival of PKP, and incidence of complications.

RESULTS

Fifty-three KLAL with AMT procedures were performed in 39 eyes, of which 23 eyes received simultaneous PKP at the time of the first KLAL. The mean follow-up was 34.0 +/- 21.5 months (range, 12-117.6). The mean period of ambulatory vision was 23.9 +/- 20.9 months (range, 0-104). The overall survival of ambulatory vision was 53.6% at 3 years and 44.6% at 5 years. The survival of ambulatory vision was significantly worse in SJS compared with other causes (67%, 81%, and 92% for groups 1, 2, and 3, respectively; P = 0.06 for group 1 versus 2, P = 0.0008 for group 1 versus 3). KLAL performed alone resulted in higher survival of ambulatory vision at 2 years (86.1% +/- 9.1%) compared with KLAL with PKP (46.9% +/- 10.6%, P = 0.100). The survival of PKP was significantly worse in SJS compared with the other causes (20.0% +/- 17.9% compared with 55.6% +/- 11.7%, respectively, P = 0.028). After 2 years, the survival of the second KLAL was better than that of the first: 68.2% +/- 15.4% compared with 27.3% +/- 13.4%, respectively (P = 0.041).

CONCLUSIONS

Ambulatory vision for a period of more than 2 years can be achieved by KLAL with or without PKP in eyes with severe ocular surface disorders caused by total LSCD. However, a progressive decline of the visual outcome and graft survival is evident with time. Performing PKP simultaneously with KLAL may be associated with a less favorable outcome. The failure of KLAL is associated with the loss of donor cells in the recipient. Augmentation of ocular surface defense is essential in securing the success of KLAL and PKP. Future modifications of the surgical procedure and of the immune suppressive protocols may improve survival of the allogeneic grafts and the final visual outcome.

Amniotic membrane transplantation after extensive removal of primary and recurrent pterygia

OBJECTIVE

To evaluate the postoperative outcome and the recurrence rate after extensive removal of primary and recurrent pterygia combined with amniotic membrane transplantation.

DESIGN

A noncomparative interventional case series.

PARTICIPANTS

Fifty-four eyes in 54 subjects with either primary (n = 33) or recurrent (n = 21) pterygia operated on by one surgeon (SCGT).

INTERVENTION

All subjects were operated on for pterygia with an extensive excision of the lesion followed by amniotic membrane transplantation and intraoperative injection of a depot corticosteroid.

MAIN OUTCOME MEASURES

Cumulative rates of conjunctival (grade 3) and corneal (grade 4) recurrence and incidence of complications.

RESULTS

The mean follow-up was 12.8 +/- 4.3 months for primary and 14.3 +/- 4.9 months for recurrent pterygia. The true recurrence rate (grade 4) was 3.0%, 9.5%, and 5.6% for primary, recurrent, and all pterygia, respectively. The cumulative proportion of recurrence-free eyes at 12 months was 0.90 +/- 0.06 for primary and 0.69 +/- 0.11 for recurrent pterygia (P = 0.047, log-rank test). Removal of the semilunar fold was associated with longer survival times (P = 0.063) and decreased failure rate (P = 0.046). A similar success rate was achieved in double-head pterygia (1 recurrence in 11 eyes).

CONCLUSIONS

Amniotic membrane transplantation is an effective and safe procedure for pterygium surgery, with a relatively low recurrence rate for both primary and recurrent pterygia. It can be a useful alternative to conjunctival autograft when a large conjunctival defect has to be covered, such as in primary double-head pterygia and in large recurrent pterygia.

Monoclonal immunoglobulin deposition disease: light chain and light and heavy chain deposition diseases and their relation to light chain amyloidosis. Clinical features, immunopathology, and molecular analysis

Monoclonal immunoglobulin deposition occurs in tissues as Congo Red binding fibrils in light chain amyloidosis, as less structured deposits in light chain deposition disease, and as similar but distinct deposits in light and heavy chain deposition disease. The nonamyloid forms were found in 13 patients who had evidence of plasmacytic dyscrasia by the immunohistochemical detection of immunoglobulin light chains of kappa or lambda class (with or without staining for a single heavy chain isotype) and by the absence of amyloid P component in tissue sections that did not show the birefringence characteristic of amyloid after Congo Red staining. All but two of the patients presented with proteinuria with or without azotemia. Clinical syndromes involving other organ systems were less common but occasionally severe. Four patients had overt multiple myeloma. Three others had hypercalcemia and mild bone marrow plasmacytosis but no lytic lesions. Analyses of immunoglobulin synthesis in bone marrow cells from seven patients showed excess light chains in all and incomplete light chains or heavy chain fragments in six, regardless of whether an intact monoclonal protein or related subunit was in the serum or urine. The fibrillar (amyloidotic) and nonfibrillar forms of monoclonal immunoglobulin deposition occur either in overt multiple myeloma or in the course of less neoplastically aggressive plasmacytic dyscrasias. Bone marrow cells from patients with either type produce immunoglobulin fragments that are related to those deposited in the affected tissues.

Suppression of interleukin 1alpha and interleukin 1beta in human limbal epithelial cells cultured on the amniotic membrane stromal matrix

AIMS

Amniotic membrane (AM) transplantation reduces inflammation in a variety of ocular surface disorders. The aim of this study was to determine if AM stroma suppresses the expression of the IL-1 gene family in cultured human corneal limbal epithelial cells.

METHODS

Human corneal limbal epithelial cells were cultured from limbocorneal explants of donor eyes on plastic or on the AM stroma. Transcript expression of IL-1alpha, IL-1beta, IL-1 receptor antagonist (RA), and GAPDH was compared with or without addition of lipopolysaccharide to their serum-free media for 24 hours using RNAse protection assay (RPA). Their protein production in the supernatant was analysed by ELISA.

RESULTS

Expression of IL-1alpha and IL-1beta transcripts and proteins was significantly reduced by cells cultured on the AM stromal matrix compared with plastic cultures whether lipopolysaccharide was added or not. Moreover, expression of IL-1 RA by cells cultured in the lipopolysaccharide-free medium was upregulated by AM stromal matrix. The ratio between IL-1 RA and IL-1alpha protein levels in AM cultures was higher than in plastic cultures.

CONCLUSIONS

AM stromal matrix markedly suppresses lipopolysaccharide induced upregulation of both IL-1alpha and IL-1beta. These data may explain in part the effect of AM transplantation in reducing ocular surface inflammation, underscoring the unique feature of the AM as a substrate for tissue engineering.

Serum cholesterol changes after midlife and late-life cognition: twenty-one-year follow-up study

BACKGROUND

Longitudinal studies have shown that high serum total cholesterol (TC) at midlife is a risk factor for dementia/Alzheimer disease. The significance of TC later in life is unclear.

OBJECTIVE

To investigate changes in serum TC from midlife to late life and their relationship with late-life cognition.

METHODS

Participants of the Cardiovascular Risk Factors, Aging and Dementia study were derived from random, population-based samples previously studied in a survey in 1972, 1977, 1982, or 1987. After an average follow-up of 21 years, 1,449 individuals aged 65 to 79 were reexamined in 1998.

RESULTS

Serum TC levels decreased in most individuals. High midlife TC represented a risk factor for more severe cognitive impairment later in life, and the values were significantly different between the control, mild cognitive impairment, and dementia groups. There were no significant differences in serum TC at reexamination. A moderate decrease in serum TC from midlife to late life (0.5 to 2 mmol/L) was significantly associated with the risk of a more impaired late-life cognitive status, even after adjusting for age, follow-up time, sex, years of formal education, midlife cholesterol, changes in body mass index, APOE epsilon4 genotype, history of myocardial infarction/stroke/diabetes, and lipid-lowering treatment.

CONCLUSIONS

The relationship between serum total cholesterol (TC) and dementia seems to be bidirectional. High midlife serum TC is a risk factor for subsequent dementia/Alzheimer disease, but decreasing serum TC after midlife may reflect ongoing disease processes and may represent a risk marker for late-life cognitive impairment.

Regulation of MMP-9 production by human corneal epithelial cells

The matrix metalloproteinases, MMP-2 and MMP-9, are known to be critical extracellular-remodeling enzymes in wound healing and other diseases of the ocular surface. This study investigated the regulation of MMP-2 and MMP-9 in human corneal epithelial cells by growth factors and pro-inflammatory cytokines (IL-1beta and TNF-alpha) they are exposed to, and by doxycycline, a medication used to treat ocular surface disease. Primary human corneal epithelial cell cultures were treated with one of the following cytokines (IL-1alpha, IL-1beta, IL-6, IL-8, TNF-alpha) or growth factors (EGF, HGF, KGF, PDGF-BB, TGF-alpha, TGF-beta), with or without their corresponding inhibitors. The conditioned media were collected after 24 hr for gelatin zymography and MMP-9 activity assay. Total RNA was extracted from the cells treated for 6 hr and was subjected to RT-PCR and Northern hybridization. Between the two gelatinases, MMP-2 and MMP-9, detected by zymography, the 92 kDa MMP-9 in the conditioned medium was markedly up-regulated by the pro-inflammatory cytokines, IL-1beta and TNF-alpha. The MMP-9 protein and activity were dose-dependently stimulated by IL-1beta or TNF-alpha at 0.1, 1.0 and 10 ng ml(-1). This up-regulation was nearly abolished by neutralizing antibodies (IL-1beta and TNF-alpha) and by IL-1 receptor antagonist. Semi-quantitative RT-PCR and Northern hybridization disclosed that the MMP-9 transcript was also markedly up-regulated in a dose-dependent manner by IL-1beta and TNF-alpha. Doxycycline (10 microg ml(-1)) suppressed MMP-9 protein level and activity, but not its mRNA, that was stimulated by IL-1beta and TNF-alpha (1 ng ml(-1)). In contrast, the 72 kDa MMP-2 was not significantly modulated by any of these cytokines. In conclusion, production of MMP-9 is stimulated by the pro-inflammatory cytokines, IL-1beta and TNF-alpha. These factors may play a role in the pathogenesis of MMP-9 mediated corneal matrix degradation. The efficacy of doxycycline in treating ocular surface diseases may be related to its ability to suppress MMP-9 production in the corneal epithelium.

Treatment of recalcitrant recurrent corneal erosions with inhibitors of matrix metalloproteinase-9, doxycycline and corticosteroids

PURPOSE

To review the efficacy of inhibitors of matrix metalloproteinase-9, corticosteroids, and doxycycline for treatment of recalcitrant recurrent corneal erosion.

METHODS

Retrospective, clinic-based, interventional case series. The medical records of seven consecutive patients who were treated between January 1995 to January 2000 for recurrent corneal erosion who had not responded to conventional therapy were reviewed. Treatment of seven eyes of seven patients consisted of oral doxycycline (50 mg, two times a day) for 2 months along with a topical corticosteroid (either methylprednisolone 1%, prednisolone acetate 1%, or fluoromethalone 0.1%) three times a day, for 2 to 3 weeks. The effects of doxycycline and methylprednisolone on metalloproteinase-9 activity in human corneal epithelial cultures were evaluated by gelatin zymography and a commercial metalloproteinase-9 activity assay kit.

RESULT

Fingernail injury in three of the seven eyes was the most common form of corneal injury. There was no evidence of epithelial basement membrane or corneal stromal dystrophy in any of the patients, although epithelial microcysts were observed in the involved area in three patients. One eye had intact elevated corneal epithelium that showed abnormal diffuse staining with fluorescein dye, and six eyes had a corneal epithelial defect at the time of presentation. In all seven eyes, pain resolved and epithelial defects healed within 2 to 10 days after initiation of therapy. No recurrence was observed during an average follow-up period of 21.9 months (range, 1.5 to 60 months). Methylprednisolone and doxycycline each produced a statistically significant decrease in amount and activity of metalloproteinase-9 in conditioned media of human corneal epithelial cultures.

CONCLUSIONS

Therapy with a combination of medications that inhibit metalloproteinase-9 produced rapid resolution and prevented further recurrence of cases of recurrent corneal erosions that were unresponsive to conventional therapies.

Bence Jones proteins and light chains of immunoglobulins. Preferential association of the V lambda VI subgroup of human light chains with amyloidosis AL (lambda)

An antiserum prepared against a lambda-Bence Jones protein from a patient (SUT) who had multiple myeloma and amyloidosis had specificity for lambda-light chains of the chemically defined variable (V) region lambda-chain subgroup lambda VI. Sequence analyses of protein SUT and of five other lambda-light chains recognized immunologically as of the V lambda VI subgroup revealed that all six proteins had the N-terminal sequence characteristic for prototype lambda VI proteins. The isotypic nature of the V lambda VI subgroup was demonstrated immunochemically: lambda VI molecules were detected among light chains isolated from the IgG proteins of each of 12 normal individuals and lambda VI antigenic determinants were also detectable on the intact IgG proteins. The frequency of lambda VI molecules among lambda-type light chains is estimated to be approximately 5% based on the finding that 5 of 91 lambda Bence Jones proteins were of the V lambda VI subgroup. Proteins of the V lambda VI subgroup, in contrast to those of the other five chemically-classified lambda chain subgroup, appear to be preferentially associated with the amyloid process as evidenced by the fact that all six lambda VI proteins were obtained from patients with amyloidosis AL and, in addition, 5 of 42 lambda-type monoclonal immunoglobulins from patients with primary or myeloma-associated amyloidosis were classified by immunodiffusion analyses as having lambda VI-type light chains.

Nerve growth factor is preformed in and activates human peripheral blood eosinophils

BACKGROUND

Recent studies have shown that nerve growth factor (NGF) is produced by and can act on several immune-inflammatory cells.

OBJECTIVES

The objective of this study was to study the effects of NGF on human peripheral blood eosinophils and assess whether these cells produce and store NGF.

METHODS

Eosinophils were purified by negative immunoselection (magnetic cell sorting systems, purity 98% to 100%) from 13 subjects (9 to 26 years old) with mild blood eosinophilia, mainly of allergic origin. Eosinophils were incubated with NGF (50 to 1000 ng/mL), and supernatants were collected for measurement of eosinophil peroxidase (EPO, 20 minutes, colorimetric enzymatic assay) and IL-6 (12 hours, ELISA). Eosinophil viability was evaluated by Trypan blue test (days 2, 3, and 4). NGF content in freshly isolated eosinophils, after ultrasound disruption, was determined with a 2-site immunoenzymatic assay. The presence of mRNA for NGF was evaluated by reverse transcription PCR.

RESULTS

NGF caused EPO release (highly significant at 1000 ng/mL NGF). IL-6 release from eosinophils was not higher than IL-6 spontaneously released into culture medium alone. NGF did not significantly affect the number of viable eosinophils. NGF was found in the eosinophil sonicates (1.5 to 17.8 pg/mL per 106 cells). Similarly, mRNA for NGF was detected by reverse transcription PCR in the freshly isolated eosinophils.

CONCLUSIONS

NGF activates human peripheral blood eosinophils from subjects with mild eosinophilia to selectively release inflammatory mediators. Eosinophils store and produce NGF. Therefore the capability of NGF to induce a secretory response and its production and storage by circulating human eosinophils suggest a possible role for NGF in conditions associated with eosinophilia, including allergic disease.

Thermodynamic instability of human lambda 6 light chains: correlation with fibrillogenicity

Certain types of human light chains have the propensity to deposit pathologically as amyloid fibrils as evidenced by the preferential association of monoclonal lambda 6 proteins with AL amyloidosis. However, the molecular features that render such proteins amyloidogenic have not been elucidated. Based upon the demonstrated relationship between the thermodynamic stability of light chains and their propensity to aggregate in vitro, we have initiated studies where the thermodynamic properties and fibrillogenic potential of two recombinant (r) V lambda 6 molecules were compared. The first protein was generated from cDNA cloned from marrow-derived plasma cells from a patient (Wil) who had AL amyloidosis and renal amyloid deposits; the second was from a patient (Jto) with multiple myeloma in whom the lambda 6 protein was deposited not as amyloid but in the form of renal tubular casts. The thermodynamic stabilities of rV lambda 6Wil and -Jto were determined from chaotropic and thermal denaturation studies. Based upon the Delta GH2O, Delta H, Delta G25 degrees C, Tm, and Cm values, the rV lambda 6Wil was less stable than its nonamyloidogenic counterpart, rV lambda 6Jto. Measurement of fibril formation using a novel in vitro fibril forming assay demonstrated that although both rV lambda 6 proteins formed fibrils in vitro, Wil had a shorter lag time and exhibited faster kinetics under physiologic conditions. Comparative amino acid sequence analyses of these two components and other lambda 6 amyloid-associated light chains revealed that the Jto protein had certain primary structural features that we posit contributed to its increased stability and thus rendered this protein nonamyloidogenic. Our studies provide the first evidence that stabilizing interactions within the V L domain can influence the kinetics of light chain fibrillogenicity.

Amniotic membrane grafts for nontraumatic corneal perforations, descemetoceles, and deep ulcers

PURPOSE

To describe the clinical outcome of amniotic membrane transplantation (AMT) for nontraumatic corneal perforations, descemetoceles, and deep ulcers.

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

Thirty-four eyes of 33 consecutive patients operated on for nontraumatic corneal perforations or descemetoceles at four academic departments of ophthalmology. Associated autoimmune disorders included rheumatoid arthritis (n = 6), Stevens-Johnson syndrome (n = 3), ocular cicatricial pemphigoid (n = 2), systemic lupus erythematosus (n = 1), and one eye with Mooren's ulcer, as well as neurotrophic, or exposure keratopathy (n = 10), postinfectious nonhealing ulcers (n = 6), and postsurgery (n = 5).

INTERVENTION

Three or four layers of amniotic membrane (AM) were applied over the ulcer bed and anchored with 10-0 nylon interrupted or running sutures. A large AM piece was used as a patch to cover the entire corneal surface.

MAIN OUTCOME MEASURES

Formation of anterior chamber depth, epithelialization of the AM grafts, and stability of the corneal stromal thickness.

RESULTS

The mean follow-up period was 8.1 +/- 5.7 (ranging from 2-23) months. A successful result was observed in 28 of 34 eyes (82.3%). Of the successful cases, 23 eyes needed one AMT procedure, whereas 5 eyes needed two procedures to achieve a successful result. In five eyes, a subsequent definitive surgical procedure such as penetrating keratoplasty or lid surgery was needed. Failure was observed in six eyes with rheumatoid arthritis, neurotrophic keratopathy, or graft melting.

CONCLUSIONS

AMT is an effective method for managing nontraumatic corneal perforations and descemetoceles. It can serve as either a permanent therapy or as a temporizing measure until the inflammation has subsided and a definitive reconstructive procedure can be performed. This treatment option is also beneficial in those countries where corneal tissue availability is limited.

Antibody-mediated resolution of light chain-associated amyloid deposits

Primary light-chain-associated (AL) amyloidosis is characterized by the deposition in tissue of monoclonal light chains as fibrils. With rare exception, this process is seemingly irreversible and results in progressive organ dysfunction and eventually death. To determine whether immune factors can effect amyloid removal, we developed an experimental model in which mice were injected with amyloid proteins extracted from the spleens or livers of patients with AL amyloidosis. Notably, the resultant amyloidomas were rapidly resolved, as compared to controls, when animals received injections of an anti-light-chain monoclonal antibody having specificity for an amyloid-related epitope. The reactivity of this monoclonal antibody was not dependent on the V(L) or C(L) isotype of the fibril, but rather seemed to be directed toward a beta-pleated sheet conformational epitope expressed by AL and other amyloid proteins. The amyloidolytic response was associated with a pronounced infiltration of the amyloidoma with neutrophils and putatively involved opsonization of fibrils by the antibody, leading to cellular activation and release of proteolytic factors. The demonstration that AL amyloid resolution can be induced by passive administration of an amyloid-reactive antibody has potential clinical benefit in the treatment of patients with primary amyloidosis and other acquired or inherited amyloid-associated disorders.

Chemical typing of amyloid protein contained in formalin-fixed paraffin-embedded biopsy specimens

The human amyloidoses represent a heterogeneous group of disorders characterized by the deposition of fibrillar protein in vital organs. Given the fact that at least 20 different molecules can form fibrils, the unambiguous identification of the type of amyloid deposited is critical to the correct diagnosis and treatment of patients with these disorders. Heretofore, this information has been inferred from particular clinical features of the disease, ancillary laboratory tests, and results of immunohistochemical analyses. However, to establish unequivocally the kind of protein that is deposited as amyloid, it is necessary to determine its chemical composition through amino acid sequencing or mass spectroscopy of material extracted from fibrillar deposits. We have developed a micromethod whereby such studies can be performed readily using sections of formalin-fixed, paraffin-embedded biopsy specimens. The ability to identify precisely the nature of the tissue deposits has diagnostic, therapeutic, and prognostic implications for patients with amyloid-associated disorders.

Is clinical depression distinct from subthreshold depressive symptoms? A review of the continuity issue in depression research

Resolving whether subthreshold depressive symptoms exist on a continuum with unipolar clinical depression is important for progress on both theoretical and applied issues. To date, most studies have found that individuals with subthreshold depressive symptoms resemble cases of major depressive disorder along many important dimensions (e.g., in terms of patterns of functional impairment, psychiatric and physical comorbidity, familiality, sleeping EEG, and risk of future major depression). However, such manifest similarities do not rule out the possibility of a latent qualitative difference between subthreshold and diagnosable depression. Formal taxonomic analyses, intended to resolve the possibility of a latent qualitative distinction, have so far yielded contradictory findings. Several large-sample latent class analyses (LCA) have identified latent clinical and nonclinical classes of unipolar depression, but LCA is vulnerable to identification of spurious classes. Paul Meehl's taxometric methods provide a potentially conservative alternative way to identify latent classes. The one comprehensive taxometric analysis reported to date suggests that self-report depression symptoms occur along a latent continuum but exclusive reliance on self-report depression measures and incomplete information regarding sample base rates of depression makes it difficult to draw strong inferences from that report. We conclude that although most of the evidence at this time appears to favor both a manifest and latent continuum of unipolar depression symptomatology, several important issues remain unresolved. Complete resolution of the continuity question would be speeded by the application of both taxometric techniques and LCA to a single large sample with a known base rate of lifetime diagnosed depressives.

Amniotic membrane transplantation for reconstruction of the conjunctival fornices

PURPOSE

To describe the clinical outcome of amniotic membrane transplantation (AMT) for fornix reconstruction in a variety of ocular surface disorders.

DESIGN

Noncomparative interventional case series.

PARTICIPANTS

Seventeen eyes in 15 patients with symblepharon. Four eyes had ocular-cicatricial pemphigoid, two eyes had symblepharon after pterygium excision, four eyes had chemical or mechanical trauma, two eyes had strabismus surgery, two eyes (one patient) had Stevens-Johnson syndrome, one eye had toxic epidermal necrolysis, and two eyes (one patient) had chronic allergic conjunctivitis.

INTERVENTION

The subconjunctival scar tissue was dissected from the episclera, and the freed conjunctival flap was recessed to the fornix. A layer of amniotic membrane (AM) was applied to cover the exposed episclera. The fornical edge of the membrane was anchored with sutures passing through the full thickness of the lid.

MAIN OUTCOME MEASURES

A deep conjunctival fornix, lack of motility restriction.

RESULTS

The mean follow-up period was 37 +/- 24 months (range, 9-84 months). Complete fornix reconstruction was demonstrated in 12 of 17 eyes (70.6%), whereas 2 eyes had a partial success, and 3 eyes (3 patients) had recurrence of symblepharon with restricted motility. In eyes that demonstrated partial success or failure, the underlying etiology was either an autoimmune disorder or a recurrent pterygium. The most successful outcome was observed in eyes with symblepharon associated with trauma.

CONCLUSIONS

AMT is an effective method of fornix reconstruction for the repair of symblepharon in a variety of ocular surface disorders. Future modifications, including an epithelial cellular component on the AM (conjunctival autograft or ex vivo expanded epithelial stem cells) may improve the outcome of this surgical procedure.

Involvement of wound-associated factors in rat brain astrocyte migratory response to axonal injury: in vitro simulation

The poor ability of mammalian central nervous system (CNS) axons to regenerate has been attributed, in part, to astrocyte behavior after axonal injury. This behavior is manifested by the limited ability of astrocytes to migrate and thus repopulate the injury site. Here, the migratory behavior of astrocytes in response to injury of CNS axons in vivo was simulated in vitro using a scratch-wounded astrocytic monolayer and soluble substances derived from injured rat optic nerves. The soluble substances, applied to the scratch-wounded astrocytes, blocked their migration whereas some known wound-associated factors such as transforming growth factor-beta 1 (TGF-beta 1), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), and heparin-binding epidermal growth factor in combination with insulin-like growth factor-1 (HB-EGF + IGF-1) stimulated intensive migration with consequent closure of the wound. Migration was not dominated by proliferating cells. Both bFGF and HB-EGF + IGF-1, but not TGF-beta 1, could overcome the blocking effect of the optic nerve-derived substances on astrocyte migration. The induced migration appeared to involve proteoglycans. It is suggestive that appropriate choice of growth factors at the appropriate postinjury period may compensate for the endogenous deficiency in glial supportive factors and/or presence of glial inhibitory factors in the CNS.

Cholesterol as a risk factor for Alzheimer's disease - epidemiological evidence

Although dementia is usually a late-life syndrome, it is now well known that pathological changes begin quite early in adulthood, outside the classical age borders of geriatric specialties. In order to design effective preventive strategies, adequate information can only be gathered by taking a life-long view of Alzheimer's disease (AD). Dementia risk is the result of exposure to both harmful and protective factors along the life course, and these factors, as well as their impact on the individual's health status, change over time. This review aims at presenting current epidemiological data on serum cholesterol levels and dietary fat intake as risk factors for dementia/AD, and at discussing the reasons and significance of contradictions between various studies. Reducing dementia risk may be possible by influencing the serum lipid profile. A more detailed characterization of the mechanisms behind the association of cholesterol (in both serum and brain) with dementia/AD, mechanisms about which little is currently known, would allow a better translation of research findings into clinical practice.

Toward cell therapy using placenta-derived cells: disease mechanisms, cell biology, preclinical studies, and regulatory aspects at the round table

Among the many cell types that may prove useful to regenerative medicine, mounting evidence suggests that human term placenta-derived cells will join the list of significant contributors. In making new cell therapy-based strategies a clinical reality, it is fundamental that no a priori claims are made regarding which cell source is preferable for a particular therapeutic application. Rather, ongoing comparisons of the potentiality and characteristics of cells from different sources should be made to promote constant improvement in cell therapies, and such comparisons will likely show that individually tailored cells can address disease-specific clinical needs. The principle underlying such an approach is resistance to the notion that comprehensive characterization of any cell type has been achieved, neither in terms of phenotype nor risks-to-benefits ratio. Tailoring cell therapy approaches to specific conditions also requires an understanding of basic disease mechanisms and close collaboration between translational researchers and clinicians, to identify current needs and shortcomings in existing treatments. To this end, the international workshop entitled "Placenta-derived stem cells for treatment of inflammatory diseases: moving toward clinical application" was held in Brescia, Italy, in March 2009, and aimed to harness an understanding of basic inflammatory mechanisms inherent in human diseases with updated findings regarding biological and therapeutic properties of human placenta-derived cells, with particular emphasis on their potential for treating inflammatory diseases. Finally, steps required to allow their future clinical application according to regulatory aspects including good manufacturing practice (GMP) were also considered. In September 2009, the International Placenta Stem Cell Society (IPLASS) was founded to help strengthen the research network in this field.