Topographic protein profiling of the age-related proteome in the retinal pigment epithelium of Callithrix jacchus with respect to macular degeneration.

In the retinal pigment epithelium (RPE) several factors within the macular compared to peripheral regions cause differences in physiological aging. The molecular mechanisms during aging in the context of topography are not well known. The proteome of RPE of different aged macular-bearing primates Callithrix jacchus was thus analysed with ion mobility mass spectrometry. Macular and periphery of neonate RPE were well differentiated from aged tissues as demonstrated by principal component analysis. This finding was mainly due to proteins involved in major developmental processes and the visual cycle. The distinction of adult from senile tissue and macular from periphery was more subtle. The hypotheses of inflammation increasing with age was supported. High expression levels of proteins related to oxidative stress (e.g., cathepsin B) and chaperones (e.g., HSP90) were detected in aged RPE as confirmed by Western blot and immunohistochemical analysis. Decreased levels of proteins participating in angiostatic properties (e.g., thrombospondin 1) and the integrity of tissue basement membranes with age (e.g., nidogen 1) were in agreement with neovascularization. This study presents targets for further investigations of the mechanisms of the aging process with the aim to elucidate predictive factors for the conversion of physiological aging into pathological conditions. SIGNIFICANCE: The current study characterized the different protein profiles of the retinal pigment epithelium (RPE) of the macula-bearing, non-human primate Callithrix jacchus during life-time. In addition, the subproteomes of macular and peripheral RPE were investigated. Differently expressed proteins described developmental processes in neonate tissue and destructive mechanisms in aged samples. Insights into the physiological aging process of the RPE and its conversion into pathophysiological conditions were gained. They assist in designing therapeutical approaches to counteract age-related diseases of the retina.

Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme.

Photoinduced charge-transfer processes play a key role for novel photovoltaic phenomena and devices. Thus, the development of ab initio methods that allow for an accurate and computationally inexpensive treatment of charge-transfer excitations is a topic that nowadays attracts a lot of scientific attention. In this paper we extend an approach recently introduced for the description of single and double excitations [M. Tassi, I. Theophilou, and S. Thanos, Int. J. Quantum Chem. 113, 690 (2013); M. Tassi, I. Theophilou, and S. Thanos, J. Chem. Phys. 138, 124107 (2013)] to allow for the description of intermolecular charge-transfer excitations. We describe an excitation where an electron is transferred from a donor system to an acceptor one, keeping the excited state orthogonal to the ground state and avoiding variational collapse. These conditions are achieved by decomposing the space spanned by the Hartree-Fock (HF) ground state orbitals into four subspaces: The subspace spanned by the occupied orbitals that are localized in the region of the donor molecule, the corresponding for the acceptor ones and two more subspaces containing the virtual orbitals that are localized in the neighborhood of the donor and the acceptor, respectively. Next, we create a Slater determinant with a hole in the subspace of occupied orbitals of the donor and a particle in the virtual subspace of the acceptor. Subsequently we optimize both the hole and the particle by minimizing the HF energy functional in the corresponding subspaces. Finally, we test our approach by calculating the lowest charge-transfer excitation energies for a set of tetracyanoethylene-hydrocarbon complexes that have been used earlier as a test set for such kind of excitations.

[Impact of age on success rate of lacrimal duct irrigation with silicone tube intubation in connatal lacrimal duct stenosis]. / Einfluss des Operationszeitpunktes auf den langfristigen Erfolg von Tränenwegsoperationen mit Schlauchintubation bei kindlicher Tränenwegsstenose.

BACKGROUND: Irrigation of the lacrimal duct with silicone tube intubation (TWS/S) remains the preferred treatment in persisting connatal lacrimal duct stenosis (kTWS). The timepoint of operation is however discussed controversely. On the one hand, it is recommended to wait for spontaneous opening of the lacrimal duct within the first year of life, on the other hand a later operation may trigger inflammatory changes within the lacrimal duct system influencing the success rate of the operation negatively. The aim of this study was to analyze the best time point of operation regarding the long-term success rate of the operation. PATIENTS/MATERIALS AND METHODS: 411 lacrimal ducts of 316 children with kTWS between 0 and 48 months of age (164 male, 156 female), who had undergone TWS with S because of kTWS at a tertiary eye care centre between 2007-2011 were included in this study. The children were divided into 6 groups of age (0-6, 7-12, 13-18, 19-24, 24-36, > 36 months) at the time of operation. The operative success was retrospectively evaluated after 36 months. The groups were compared and differences in late success rate analyzed statistically. RESULTS: The average success of operation of TWS/S in kTWS was 89 % (366 of 411 lacrimal ducts). The success rate of operation differed between the groups. If operated at the age of 0-6 months the operation was successful in 94 %, at the age 7-12 months in 91 %, between 13-18 months in 90.5 %, from 19-24 months in 88 %, and from 25-36 months in only 84.5 %. The success rate was therewith at the age of 25-36 months significantly lower than at the age of 0-6 months (p < 0.05). CONCLUSION: TWS/S in kTWS has overall a very high rate of success. The success of the operation decreases however in correlation with age at time of operation and shows with > 25 months significantly poorer results than at 0-6 months. The choice of the best time point for operation merits further investigation.

Dysfunctional uveoscleral pathway in a rat model of congenital glaucoma.

UNLABELLED: The purpose of the study was to investigate the presence of the uveoscleral pathway in the normotensive rat (NR) and in a rat model of congenital glaucoma (CGR). We injected the fluorescent tracer 70-kDa dextran rhodamine B in the anterior chamber of four NRs and four CGRs. At 10 and 60 minutes after injection, rats were euthanized by CO2 inhalation and eyes were enucleated. Cryosections were prepared and analyzed using fluorescent microscopy. Hematoxylin-eosin staining and electron microscopy of the anterior chamber angle (ACA) were performed. At 10 minutes after injection, fluorescent tracer was detected in the iris root and ciliary processes of NRs and CGRs. At 60 minutes, NRs showed prominent signal in the suprachoroidal, whereas, in the CGRs, tracer was barely detectable. Histology of the anterior chamber revealed the presence of an open ACA and electron microscopy confirmed the normal structure of the ciliary body in CGRs. CONCLUSIONS: Our results document the presence of an uveoscleral pathway in the normotensive rat. The rat model of congenital glaucoma shows severe impairment of the uveoscleral pathway, suggesting that alterations of the uveoscleral outflow might play a role in the pathogenesis of CG.

Double excitations from modified Hartree Fock subsequent minimization scheme.

Doubly excited states have nowadays become important in technological applications, e.g., in increasing the efficiency of solar cells and therefore, their description using ab initio methods is a great theoretical challenge as double excitations cannot be described by linear response theories based on a single Slater determinant. In the present work we extend our recently developed Hartree-Fock (HF) approximation for calculating singly excited states [M. Tassi, I. Theophilou, and S. Thanos, Int. J. Quantum Chem. 113, 690 (2013)] in order to allow for the calculation of doubly excited states. We describe the double excitation as two holes in the subspace spanned from the occupied HF orbitals and two particles in the subspace of virtual HF orbitals. A subsequent minimization of the energy results to the determination of the spin orbitals of both the holes and the particles in the occupied and virtual subspaces, respectively. We test our method, for various atoms, H2 and polyene molecules which are known to have excitations presenting a significant double excitation character. Importantly, our approach is computationally inexpensive.

[Medical malpractice in ophthalmology]. / Behandlungsfehler in der Augenheilkunde.

BACKGROUND: The increasing number of patients taking action for medical malpractice (MM) is a burden for the medical practitioners accused. After the assessment through an arbitration committee, which is free of cost for the patients,a large number of lawsuits can be avoided. Discussion of patient complaints and analyzing cases of MM is an important concern for the medical community in order to reduce errors in treatment and to contribute to patient safety. MATERIAL AND METHODS: The patient applications to the arbitration committee of the medical association of North-Rhine ("Gutachterkommission Nordrhein") for review of MM in the field of ophthalmology in the years 1999-2010 were analyzed statistically. RESULTS: In the years 1999-2010 a total of 583 cases were related to ophthalmology (3% of all cases) and in 122 cases (21%) MM was recognized by the committee. In 61% of the cases MM was caused by errors in diagnosis, in 24% by errors in processes and in 15% by errors in surgical procedures. CONCLUSIONS: The proportion of ophthalmological cases in the total number of MM cases is low. Most errors in diagnosis are caused by the lack of basic diagnostic on examination procedures. Errors in processes are caused by instrumental errors and deficient communication. An important reason for errors in surgical procedures is a deficient management of complications. A standardized workflow of medical examinations and a quality management can help to avoid MM.

Everolimus improves experimental autoimmune uveoretinitis.

The efficacy and action mechanism of everolimus in the treatment of experimental autoimmune uveoretinitis (EAU) was analyzed. Disease was induced in B10.RIII mice by immunization with human interphotoreceptor-retinoid-binding protein peptide 161-180 (hIRBPp161-180). Everolimus was administered by oral gavage (5 mg/kg/d) beginning either two days before or 14 days after immunization. Everolimus significantly reduced the histopathological uveitis score compared to sham-treated mice. To examine the effect on the antigen-specific immune response, proliferation ([(3)H]-thymidine test) and delayed-type hypersensitivity (DTH) response were measured. Furthermore, content of T-helper-1, -2, and -17 cytokines were analyzed intraocularly (Bead Array) and in cell culture supernatants from splenocytes (sandwich ELISA). To study the effect on the humoral immune response the presence of antigen-specific serum antibodies was tested (indirect ELISA). The DTH, the humoral immune response, the proliferation of splenocytes and the intraocular Th1, Th2, Th17 cytokine content and in vitro production of Th1 and Th17 cytokines were impaired after everolimus treatment. The study of CD4+CD25+FoxP3+ regulatory T cells (T(reg)) in peripheral blood, draining lymph nodes, and spleen by flow cytometry showed an increased number of splenic T(reg) in mice of the everolimus therapy group. Furthermore the T(reg) of these mice had a higher suppressive capacity than cells from sham-treated mice. These results indicate that the immunosuppressive effect of everolimus on EAU was associated with the suppression of pathogenic effector responses and induction of regulatory T cells.

Nicotinamide reduces photodynamic therapy-induced immunosuppression in humans.

BACKGROUND: The immune suppressive effects of topical photodynamic therapy (PDT) are potential contributors to treatment failure after PDT for nonmelanoma skin cancer. Nicotinamide (vitamin B(3) ) prevents immune suppression by ultraviolet radiation, but its effects on PDT-induced immunosuppression are unknown. OBJECTIVES: To determine the effects of topical and oral nicotinamide on PDT-induced immunosuppression in humans. METHODS: Twenty healthy Mantoux-positive volunteers received 5% nicotinamide lotion or vehicle to either side of the back daily for 3 days. Another group of 30 volunteers received 500 mg oral nicotinamide or placebo twice daily for 1 week in a randomized, double-blinded, crossover design. In each study, methylaminolaevulinate cream was applied to discrete areas on the back, followed by narrowband red light irradiation (37 J cm(-2) ) delivered at high (75 mW cm(-2) ) or low (15 mW cm(-2) ) irradiance rates. Adjacent, nonirradiated sites served as controls. Delayed-type hypersensitivity (Mantoux) reactions were assessed at treatment and control sites to determine immunosuppression. RESULTS: High irradiance rate PDT with vehicle or with placebo caused significant immunosuppression (equivalent to 48% and 50% immunosuppression, respectively; both P < 0·0001); topical and oral nicotinamide reduced this immunosuppression by 59% and 66%, respectively (both P < 0·0001). Low irradiance rate PDT was not significantly immunosuppressive in the topical nicotinamide study (15% immunosuppression, not significant), but caused 22% immunosuppression in the oral study (placebo arm; P = 0·006); nicotinamide reduced this immunosuppression by 69% (P = 0·045). CONCLUSIONS: While the clinical relevance of these findings is currently unknown, nicotinamide may provide an inexpensive means of preventing PDT-induced immune suppression and enhancing PDT cure rates.

[Concomitant cellular reactions in optic nerve siderosis existing for 30 years]. / Zelluläre Begleitreaktionen bei seit 30 Jahren bestehender Siderosis N. optici.

Metal foreign bodies located in the optic nerve are a rare clinical picture and sooner or later often associated with vision loss. We report on a patient who had a foreign body in the optic nerve for 30 years. Histochemical analysis of the optic nerve after the requisite enucleation with complete functional loss of the eye revealed amazing results. Even 30 years after entry of the foreign body into the optic nerve neuronal structures with organized axons surrounded by cytoblasts, glial cells, and immunocompetent cells still remoined. These findings hold out hope and may serve as the starting point for regenerative medicine to potentially restore neuronal function.

[Bacteriology of occluded nasolacrimal ducts in infants]. / Bakterielles Keimspektrum bei kindlichen Tränenwegsstenosen.

BACKGROUND: Connatal lacrimal duct stenosis (cLDO) commonly causes purulent bacterial dacyrocystitis. The recommended treatment of choice is up to the sixth month of life a conservative antimicrobiological therapy. After the sixth month lacrimal duct irrigation with silicone tube intubation remains the gold standard. Our purpose was to analyse the current bacterial spectrum in cLDO and to compile a bacterial resistogram in order to specify antimicrobiological therapy. METHODS: 66 samples from the lacrimal duct of 6- to 16-month-old children (41 female, 25 male) were obtained by collecting the refluxing liquids with cotton wool swabs after irrigation of the lacrimal drainage system with sterile saline during lacrimal duct surgery. Cultures were incubated aerobically and anaerobically and the infectious agents were isolated. Sensitivity testing was performed for each isolate, testing 8 different commonly used local antibiotics. Data were statistically analysed using SPSS. RESULTS: Cultures were positive in cLDO in 97 %, showing co-colonisation in 87 % with up to five bacterial strains. Gram-positive bacteria were seen in 72 % of the isolates in cLDO with Streptococcus pneumoniae (31 %) being the most abundant strain, followed by Staphylococcus aureus (13 %) and S. epidermidis (13 %). In 85 % of the samples at least one Gram-negative rod was present, most often Branhamella (12 %), followed by Haemophilus influenzae (11 %). Sensitivity testing revealed chloramphenicol, fusidic acid and ciprofloxacin/levofloxacin to be the most effective drugs in cLDO, whereas erythromycin and gentamycin turned out to be insufficient in treating cLDO. CONCLUSION: Bacterial colonisation plays a crucial role in cLDO, showing a positive culture in 97 % with frequent co-colonisation of several bacterial strains (often in combination with at least one Gram-negative strain). The sampling of a microbiological probe of the lacrimal duct is recommended at least in therapy-refractory cases. Current bacteria in cLDO can be effectively treated with chloramphenicol, fusidic acid and ciprofloxacin. The commonly used antibiotics erythromycin and gentamicin are inappropriate as monotherapeutics.

[Factors influencing the long-term success of lacrimal duct surgery and the prognostic value of dacryocystography]. / Einflussfaktoren auf den langfristigen Erfolg von Tränenwegsoperationen und der prognostische Wert der Dakryozystografie.

BACKGROUND: Irrigation of the lacrimal duct with silicone tube intubation, endoscopic microdrill dacryoplasty and external dacryocystorhinostomy (DCR) are commonly used in lacrimal duct surgery. Dacryocystography (DCG) is one of the standard procedures in preoperative imaging. This study evaluates the influence of individual parameters and the prognostic meaning of preoperative DCG on the success rates after lacrimal duct surgery, in order to predict more precisely the long-term outcome after different operative paradigms. MATERIALS AND METHODS: 145 patients (mean age 60 years; 32 % male) with lacrimal stenosis, who underwent lacrimal duct surgery in the University Eye Hospital Münster during 2002 were included in this retrospective study. Individual parameters (age, gender, preoperative duration of symptoms, lacrimal sac area and operative procedures) were recorded. The lacrimal sac area of each patient was calculated from preoperative DCG imaging. The individual parameters and the prognostic relevance of preoperative DCG were statistically analysed with regards to the long-term success rate after different surgical procedures. Criteria for success were an asymptomatic patient and a successful probing and irrigation of the lacrimal duct system at follow-up at 24 to 36 months after lacrimal duct surgery. RESULTS: With a mean success rate of 79 %, DCR was most effective regarding long-term outcome. Particularly in elderly patients DCG was superior to minimal-invasive procedures. The mean area of the lacrimal sac, calculated from DCG imaging, was 18 mm (2). There was a significant correlation (p = 0.001) between the area of the lacrimal sac and long-term success of DCR. CONCLUSION: Endoscopic microdrill dacryoplasty and DCR have the most successful options in the treatment of lacrimal stenosis. DCG was the most effective procedure in elderly patients. An enlargred lacrimal sac proved to be a positive prognostic factor for the long-term success of DCR.

[Ophthalmological symptoms as key findings in neurosyphilis--diagnosis and therapy]. / Ophthalmologische Symptomatik als Schlüsselbefund der Neurosyphilis--Diagnose und Therapie.

BACKGROUND: The incidence of neurosyphilis, one of the late manifestations of syphilis, is reemerging. Affection of the eye is often associated with the disease. It may present with various clinical symptoms, leading to diagnostic difficulties. In cases of early diagnosis and adequate treatment the prognosis of the disease is good. PURPOSE: The purposes of this study are 1. to analyse clinical manifestations of patients with neurosyphilis on ophthalmological symptoms and 2. to demonstrate the course of the disease and the visual outcome in patients with optic nerve affection in neurosyphilis treated with standard therapy (penicillin G) or adjunct steroids. METHODS: We performed 1. a retrospective analysis of all 23 patients who were treated for neurosyphilis between 2000-2008 at this centre and 2. evaluated a case series of 4 patients with optic nerve affection in neurosyphilis who were treated with penicillin and adjunct methylprednisolone. RESULTS: 91% of the patients with neurosyphilis showed ocular affection in various presentations. The optic nerve was affected in 78%. In 43% ocular symptoms were the exclusive sign of the neurosyphilis. In all patients who were treated with penicillin, visual acuity improved. Adjunct treatment with methylprednisolone resulted in complete visual recovery in two cases. CONCLUSION: Ocular symptoms serve as the key diagnostic findings in neurosyphilis. Treatment of choice is penicillin G. Adjunct treatment with methylprednisolone may improve the visual outcome in patients with optic nerve involvement.

Acute keratoconus induced by hypothyroxinemia during pregnancy.

Keratoconus is a bilateral non-inflammatory corneal ectasia with an incidence of approximately 1 per 2000 in the general population. The etiology of keratoconus is multifactorial, although not completely understood. Several clinical observations suggest that thyroid gland dysfunction is associated with keratoconus pathophysiology. Pregnancy represents a major alteration in the maternal endocrinologic status characterized by modified function of the thyroid gland. We report on a 33-yr-old pregnant women suffering from keratoconus, who presented simultaneously with a remarkable deterioration of the disease during gestation and with thyroid gland dysfunction. Acute keratoconus in this patients coincided with the lowest plasma T4 level reached during pregnancy. During the third trimester of gestation, the keratoconus receded significantly. Here we provide direct evidence in support of a possible linkage between keratoconus and thyroid gland dysfunction, assumed by previous clinical observations. This case report is the first to suggest that changes in maternal thyroid hormone levels during pregnancy can aggravate the progression of keratoconus.

Cholinergic inhibition by botulinum toxin in a rat model of congenital glaucoma raises intraocular pressure.

BACKGROUND: Cholinergic receptors are crucially involved in the regulation of intraocular pressure (IOP). Muscarinic agonists in the trabecular meshwork tissue increase aqueous humour outflow facility by a direct stimulation of ciliary muscle contraction. We investigated the contribution of cholinergic state to IOP regulation. METHODS: Intracameral injections of botulinum toxin A (BTA) were applied in a group with four normotensive rats and a group with four glaucoma rats (genetic glaucoma model). BTA is a potent neurotoxin which inhibits presynaptic cholinergic transmission for 6-8 weeks. The same amount of saline was injected in a third group of four normotensive rats (sham condition). IOP measurements were performed preoperatively, as well as 1, 2 and 4 weeks postoperatively. Afterwards, the rat eyes were removed and subjected to immunhistochemistry and western blotting analysis using antibodies against choline acetyltransferase (CHAT). RESULTS: Mean IOP in both normotensive groups was unaltered compared with the preoperative status. The glaucoma group showed a significant increase in the mean IOP (Student test, p<0.05) and a signal reduction for CHAT by immunolabelling in the trabecular meshwork compared with the other two groups. Western blotting confirmed the decreased expression of CHAT. CONCLUSION: Our results suggest that modification of the cholinergic status in the normotensive eye does not significantly affect the IOP; cholinergic regulation of the ciliary trabecular meshwork may have differential levels of control, apart from the ciliary muscle contraction. Moreover, it seems that differential expression of the muscarinic receptors may be responsible for the decreased trabecular cholinergic state occurring in this rat model of glaucoma.

Reduced expression of the gap junction protein Connexin 43 in keratoconus.

PURPOSE: The purpose of the present study was to examine whether keratoconus, which is a bilateral noninflammatory corneal ectasia with multifactorial aetiology, shows altered expression of Connexin (Cx43). Cx43 is an important gap junction protein that contributes crucially to epithelial and stromal integrity of cornea. METHODS: Eight keratoconic human corneal buttons were examined with immunohistochemistry and Western blotting and compared with eight normal human corneal buttons, to unravel changes in Cx43 expression. RESULTS: All normal corneas exhibited similar epithelial Cx43 expression patterns, with the protein located in the basal epithelial layer. In contrast, some keratoconic corneas showed an altered pattern of immunostaining and Western blotting confirmed a decreased expression of Cx43 in keratoconic corneas. CONCLUSIONS: Our results indicate that a decrease in Cx43 amount together with functional alteration of the protein is associated with keratoconus pathophysiology However, these changes apply only to some of the corneas examined and may not generally account for the development of keratoconus.

Spin contamination for Hartree-Fock, optimized effective potential, and density functional approximations.

In an earlier paper [S. Thanos and A. K. Theophilou J. Chem. Phys. 124, 204109 (2006)], we found an explicit formula for the expansion of a Slater determinant |Phi(M)> in terms of eigenstates of S(2). In this paper, we use the same formula to determine the spin contamination S(con) of the unrestricted single determinant approximations, i.e., Hartree-Fock, optimized effective potential, and density functional theory. We derived an expression which gives S(con) in terms of the overlap of the spatial parts of the spin up and spin down "corresponding" orbitals. It was found that S(con) does not depend on M, the eigenvalue of S(z), at least for the lower order approximations, i.e., when || is large. In this case, the predominant coefficient of the expansion assumes its maximum value when S=M. However, for the class of solutions that || is small, the spin L of the largest coefficient increases with the number of unpaired electrons. We also derived the explicit form of the expansion states.

Implantable visual prostheses.

Visual impairment and blindness is primarily caused by optic neuropathies like injuries and glaucomas, as well as retinopathies like agerelated macular degeneration (MD), systemic diseases like diabetes, hypertonia and hereditary retinitis pigmentosa (RP). These pathological conditions may affect retinal photoreceptors, or retinal pigment epithelium, or particular subsets of retinal neurons, and in particular retinal ganglion cells (RGCs). The RGCs which connect the retina with the brain are unique cells with extremely long axons bridging the distance from the retina to visual relays within the thalamus and midbrain, being therefore vulnerable to heterogeneous pathological conditions along this pathway. When becoming mature, RGCs loose the ability to divide and to regenerate their accidentally or experimentally injured axons. Consequently, any loss of RGCs is irreversible and results to loss of visual function. The advent of micro- and nanotechnology, and the construction of artificial implants prompted to create visual prostheses which aimed at compensating for the loss of visual function in particular cases. The purpose of the present contribution is to review the considerable engineering expertise that is essential to fabricate current visual prostheses in connection with their functional features and applicability to the animal and human eye. In this chapter, 1) Retinal and cortical implants are introduced, with particular emphasis given to the requirements they have to fulfil in order to replace very complex functions like vision. 2) Advanced work on material research is presented both from the technological and from the biocompatibility aspect as prerequisites of any perspectives for implantation. 3) Ultimately, experimental studies are presented showing the shaping of implants, the procedures of testing their biocompatibility and essential modifications to improve the interfaces between technical devices and the biological environment. The review ends by pointing to future perspectives in the rapidly accelerating process of visual prosthetics and in the increasing hope that restoration of the visual system becomes reality.

Bounds on the overlap of the Hartree-Fock, optimized effective potential, and density functional approximations with the exact energy eigenstates.

In this paper, we examine the limits of accuracy of the single determinant approximations (Hartree-Fock, optimized effective potential, and density functional theory) to the exact energy eigenstates of many electron systems. We show that an approximate Slater determinant of S(z)=M gives maximum accuracy for states with S=M, provided that perturbation theory for the spin up minus spin down potential is applicable. The overlap with the exact energy eigenstates with S not equal M is much smaller. Therefore, for the case that the emphasis is on wave functions, one must use symmetry preserving theories, although this is at the expense of accuracy in energy.