[Neuropsychiatric symptomatology in post-COVID syndrome. Intervention proposal and referral from primary care]. / Sintomatología neuropsiquiátrica en el síndrome post-COVID. Propuesta de manejo y derivación desde atención primaria.

SARS-CoV-2 infection is a multiorgan disease with a wide spectrum of clinical manifestations, including neurological and psychiatric, which are expressed in all stages of the disease and often has long-term symptoms, called post-COVID syndrome. Among the neuropsychiatric symptoms derived from this syndrome, in this article we focus on headache, cognitive impairment, taste and smell alterations, depression, anxiety and sleep disorders. Intervention algorithms for these symptoms in primary care establishing criteria for referral to specialized care are proposed.

Development and chemical characterization of biodegradable polymeric implants containing sirolimus for the treatment of malignant solid tumors.

The use of sirolimus and its analogs has been evaluated in studies aimed at combating several types of cancer; however, because of the limited bioavailability of the drug, the search for new forms of administration is required. Biodegradable polymeric implants containing sirolimus were developed and assessed as an alternative method of drug administration. Implants containing 25 % (w/w) sirolimus were prepared employing the polymer matrices chitosan, polycaprolactone and poly(lactic-co-glycolic acid) (PLGA) in two proportions: PLGA 50:50 and PLGA 75:25. Thermal analysis techniques such as thermogravimetry and differential scanning calorimetry, combined with x-ray diffraction were used to characterize and evaluate the compatibility of the constituents of the formulation. No incompatibilities were found between the components, but drug amorphization was observed in all samples. Implants made from the polymers chitosan and PCL may accelerate the degradation of SRL when these polymers are dissolved in methanol at 50 °C. HPLC analysis showed that the implant prepared with PLGA 75:25 did not present degradation products and maintained its appropriate drug content, even when dissolved in methanol and heated to 50 °C. Therefore, it represents the most suitable biodegradable polymer for use in implants developed for the treatment of malignant solid tumors. However, it is still necessary to further study the drug effects after amorphization of the crystal and also to perform stability and solubility analysis.

Comparison of cytotoxicity, genotoxicity and immunological inflammatory biomarker activity of several endodontic sealers against immortalized human pulp cells.

AIM: To establish an SV40 T-Ag-transfected cell line of human pulp-derived cells in order to compare the cytotoxicity, genotoxicity and to investigate the activities of immunological biomarkers of several endodontic sealers. METHODOLOGY: Primary human pulp cells and transfected cells were cultured. Cell morphology and proliferation were analysed, and the expression of cell-specific gene transcripts and proteins was detected by RT-PCR and immunohistochemistry. Transfection of human pulp-derived cells resulted in an immortalized cell line retaining phenotypic characteristics from the primarily cells tested. The SV40 T-Ag-transfected cells were cultured and stimulated by sealers (Apexit Plus, Real Seal, AH Plus, and EndoREZ) to evaluate the cytotoxicity and genotoxicity by MTT and MTN assays, respectively. Immunological inflammatory biomarkers (IL6, IL8 and TNF-α) were determined by ELISA assay. The differences between median values were statistically analysed using Kruskal-Wallis and Dunn's tests at 5% significance level. RESULTS: The cytotoxicity assay revealed that multimethacrylate (Real Seal) was the most cytotoxic sealer (P < 0.05) and exhibited the highest inflammatory potential against the SV40 T-Ag-transfected cells (P < 0.05). All root canal sealers tested were able to stimulate the immortalized pulp cells to produce IL-6, IL-8 and TNF-α, with differences in relation to the control group (P < 0.05). Higher levels of IL-6, IL-8 and TNF-α were found in cell supernatant after stimulation with multimethacrylate (Real Seal) compared to all other sealers tested (P < 0.05). No differences were found comparing epoxy resin-based sealer (AHPlus), single-methacrylate sealer (EndoREZ) and calcium hydroxide-based sealer (Apexit Plus), regardless of the cytokine investigated (all P > 0.05). CONCLUSIONS: A SV40 T-Ag-transfected cell line of human pulp-derived cells was established. The methacrylate resin-based sealer (Real Seal) exhibited the greatest cytoxicity and inflammatory potential against immortalized pulp cells compared to an epoxy resin-based sealer (AH Plus), a methacrylate-based sealer (EndoRez) and a calcium hydroxide-based sealer (Apexit).

Public resource usage in health systems: a data envelopment analysis of the efficiency of health systems of autonomous communities in Spain.

OBJECTIVES: The efficiency in the management of public resources is one of the main pillars of the welfare state. The objective of this work is to analyze the efficiency of the public resources that regional governments in Spain (Autonomous Communities (AC)) invest in health systems (HS). STUDY DESIGN: A dataset from of the Ministry of Health, Social Services and Equality of Spain has been used, which contains the most important indicators from the National HS. The following variables have been chosen in this study: the health care expenses per resident, the percentage of this investment that is forwarded to labour expenses, frequency of hospital care services, frequency of specialized external health care services and, primary health care services in medicine and nursing per resident. METHODS: To this end, Data Envelopment Analysis (DEA) is applied, which enables researchers and managers to obtain measurements of efficiency of the analyzed regions, and to propose corrective steps to achieve efficiency for inefficient HS. Moreover, the super-efficiency measurement is shown for a constant and a variable scale. RESULTS: The results show that there are three groups of AC, first a group composed by six HS that are globally efficient, a second group composed by eight HS that are globally inefficient, and a third group composed by three HS that are efficient in some terms and their efficiency can be improved. CONCLUSIONS: It is concluded that DEA is an appropriate method for evaluating efficiencies of health systems and giving the adjustments for the application of economic, social and organizational policies to improve their efficiencies.

Goat milk during iron repletion improves bone turnover impaired by severe iron deficiency.

The effect of goat or cow milk-based diets, with either normal Fe content or an Fe overload, on bone turnover and the mineralization process was studied in control and anemic rats during chronic Fe repletion. One hundred eighty male Wistar rats were studied during a pre-experimental period of 40 d in which they were randomly divided into 2 groups, a control group receiving the AIN-93G diet with normal Fe content (45 mg/kg of diet) and the Fe-deficient group receiving the AIN-93G diet with low Fe content (5mg/kg of diet) for 40 d. After the pre-experimental period, the rats were fed for 10, 30, or 50 d with goat or cow milk-based diets with a normal Fe content (45 mg/kg of diet) or an Fe overload (450 mg/kg of diet). In anemic rats, goat milk with normal Fe content increased levels of the biomarker of bone formation N-terminal propeptides of type I procollagen and diminished parathyroid hormone levels after only 10 d of supplying this diet, indicating the beginning of restoration of the bone demineralization induced by the anemia, which was not observed with cow milk. After 30 d of supplying the milk-based diets with normal Fe content or an Fe overload, biomarkers of bone formation and bone resorption were not different between control and anemic rats, indicating that the bone demineralization induced by the Fe-deficiency anemia had recovered, although the process of stabilization of bone turnover began earlier in the animals fed goat milk. In addition, a higher Ca deposit was observed in femur, which positively affects bone mineralization, as well as an increase of Fe in sternum, which indicates that the hematopoietic process essentially recovered earlier on the goat milk diet compared with the cow milk diet.

Risk factors, pre-morbid functioning and episode correlates of neurological soft signs in drug-naive patients with schizophrenia-spectrum disorders.

BACKGROUND: There is a lack of consistent evidence regarding associations of neurological soft signs (NSS) with illness-related variables in schizophrenia. This study examined NSS in first-episode psychotic patients with respect to their factor structure and associations with risk factors, pre-morbid characteristics, psychopathology and spontaneous extrapyramidal syndromes. METHOD: First-episode, drug-naive patients with schizophrenia-spectrum disorders (n=177) were assessed for NSS using the Neurological Evaluation Scale, and its 26 constituting items were factor analysed. The identified neurological dimensions were then entered into hierarchical regression models as outcome dependent variables of a set of predictors including risk factors (familial loading for schizophrenia, obstetric complications), pre-morbid characteristics (neurodevelopmental delay, symptoms of attention deficit-hyperactivity disorder, pre-morbid functioning), psychopathological domains (reality distortion, disorganization, negative symptoms, mania, depression, catatonia) and spontaneous extrapyramidal syndromes (parkinsonism, dyskinesia, akathisia). RESULTS: Five neurological domains were identified: sequencing, release signs, sensory integration, abnormal movements and coordination. Multivariate analyses showed independent associations (p<0.01) of sequencing with familial liability to schizophrenia, deterioration of pre-morbid adjustment and parkinsonism; release signs with obstetric complications, catatonic symptoms and parkinsonism; sensory integration with familial liability to schizophrenia; abnormal movements with familial liability to schizophrenia, obstetric complications, parkinsonism and dyskinesia; and coordination with neurodevelopmental delay. The empirically derived factors explained additional variance over and above that explained by subscale scores across the examined variables. CONCLUSIONS: Familial liability to schizophrenia, obstetric complications, neurodevelopmental delay, deterioration in pre-morbid functioning and observable motor disorders appear to contribute independently to domains of neurological dysfunction. The findings support a neurodevelopmental model of NSS in schizophrenia.

GAPD and tubulin are suitable internal controls for qPCR analysis of oral squamous cell carcinoma cell lines.

The selection of housekeeping genes is critical for gene expression studies. To address this issue, four candidate housekeeping genes, including several commonly used ones, were investigated in oral squamous cell carcinoma cell lines. A simple quantitative RT-PCR approach was employed by comparing relative expression of the four candidate genes within two cancerous cell lines (HN6 and HN31) and one noncancerous cell line (HaCaT) treated or not with EGF and TGF-beta1. Data were analyzed using ANOVA followed by the NormFinder software program. On this basis, stability of the candidate housekeeping genes was ranked and non statistical differences were found using ANOVA test. On the other hand, the NormFinder was able to show that GAPD and TUBB presented the less variable results, representing appropriated housekeeping genes for the samples and conditions analyzed. In conclusion, this study suggests that the GAPD and the TUBB represent adequate normalizers for gene profiling studies in OSCC cell lines, covering, respectively, high and low expression levels genes.

Biofilm microbial communities of denture stomatitis.

INTRODUCTION: Denture stomatitis is a common lesion that affects denture wearers. Its multifactorial etiology seems to depend on a complex and poorly characterized biofilm. The purpose of this study was to assess the composition of the microbial biofilm obtained from complete denture wearers with and without denture stomatitis using culture-independent methods. METHODS: Samples were collected from healthy denture wearers and from patients with denture stomatitis. Libraries comprising about 600 cloned 16S ribosomal DNA (rDNA) bacterial sequences and 192 cloned eukaryotic internal transcribed spacer (ITS) region sequences, obtained by polymerase chain reactions, were analyzed. RESULTS: The partial 16S rDNA sequences revealed a total of 82 bacterial species identified in healthy subjects and patients with denture stomatitis. Twenty-seven bacterial species were detected in both biofilms, 29 species were exclusively present in patients with denture stomatitis, and 26 were found only in healthy subjects. Analysis of the ITS region revealed the presence of Candida sp. in both biofilms. CONCLUSION: The results revealed the extent of the microbial flora, suggesting the existence of distinct biofilms in healthy subjects and in patients with denture stomatitis.

Bacterial diversity in aphthous ulcers.

INTRODUCTION: Recurrent aphthous ulcers are common lesions of the oral mucosa of which the etiology is unknown. This study aimed to estimate the bacterial diversity in the lesions and in control mucosa in pooled samples using a culture-independent molecular approach. METHODS: Samples were collected from ten healthy individuals and ten individuals with a clinical history of recurrent aphthous ulcers. After DNA extraction, the 16S ribosomal RNA bacterial gene was amplified by polymerase chain reaction with universal primers; amplicons were cloned, sequenced and matched to the GenBank database. RESULTS: A total of 535 clones were analyzed, defining 95 bacterial species. We identified 62 putative novel phylotypes. In recurrent aphthous ulcer lesions 57 phylotypes were detected, of which 11 were known species. Control samples had 38 phylotypes, five of which were already known. Only three species or phylotypes were abundant and common to both groups (Gemella haemolysans, Streptococcus mitis strain 209 and Streptococcus pneumoniae R6). One genus was found only in recurrent aphthous ulcer samples (Prevotella) corresponding to 16% of all lesion-derived clones. CONCLUSION: The microbiota found in recurrent aphthous ulcers and in the control groups diverged markedly and the rich variety of genera found can provide a new starting point for individual qualitative and quantitative analyses of bacteria associated with this oral condition.

Efeito do ultra-som e do d-pantenol na regeneracao tegumentar / Effect of ultrasound and dexpanthenol on wound healing

Estudar os efeitos dos tratamentos com ultra-som (US) e d-pantenol (d-p) na reparacao tegumentar em ratos por meio de analise histoetrica e histopatologica. Metodo: foram utilizados 50 ratos wistar, anestesiados por Thionembutal sodico (50 mg/kg), dos quais foi retirado 1cm2 de pele na rehiao dorsal, sendo que 25 foram submetidos a tratamento diario por 7 dias e 25 por 14 dias. Os grupos experimentais (n=5) foram: controle (C), gel (G), US (3MHz, 0,1 W/cm2, 1 minuto, modo continuo), d-p na concentracao de (10 por cento) e US+d-p. seccoes de 6 um de espessura da lesao foram procesados para coloracao em Hematoxilina-Eosina. A re-epitelizacao e o numero de fibroblastos e leucocitos foram obtidos num processador de imagens (Software Imagem Pro-Plus) e analisados pelo teste ANOVA, seguido de Tukey para comparacao da medias. Resultados: a re-epitelizacao dos grupos US(1869,6+-238,4 um) e US+d-p(2167,7+-232 um) foi maior (p<-0,05) em relacao ao C(987,7+-146,8 um), mas nao diferiram entre si. O numero de fibroblastos no grupo US (419+-37) com sete dias de tratamento foi significativamente maior em relacao aos demais grupos: (C:250+-17), (d-p:296+-49) e (US+d-p:274+-18). No grupo US, tratado por sete dias, a media de leucocitos (134+-15) foi menor (p<-0,05) em relacao ao C (253+-37), d-p (222+-29) e US+d-p (153+-14), evidenciando seu efeito na fase inicial do processo inflamatorio. Conclusoes: o US acelera o processo de reparo, bem como associado ao d-p. Porem, essa associacao dos tratamentos, US+d-p, n'ao mostrou resultados significativos em relacao ao tratamento com US isolado

Goat milk feeding causes an increase in biliary secretion of cholesterol and a decrease in plasma cholesterol levels in rats.

The hypocholesterolemic effect of goat milk with respect to cow milk observed in a previous study led us to examine the influence of goat and cow milk in the diet on certain aspects of biliary physiology in normal rats. The fat content in all diets was 10% but the lipid quality was varied: the standard diet was based on virgin olive oil, and the other 2 diets included fat obtained from lyophilized cow milk and goat milk. We characterized the bile secretion, including biliary phospholipid, cholesterol, and bile acid outputs, the interrelation between bile acids and bile lipids, and the lithogenic index. The consumption of goat milk in the diet, compared with that of cow milk, caused an increase in the biliary secretion of cholesterol together with a decrease in plasma cholesterol concentration, whereas values for bile phospholipids, biliary acid concentrations, and the lithogenic index remained normal. Moreover, consumption of this type of milk decreased plasma triglyceride concentration and therefore had a positive effect, similar to that of olive oil (standard diet), on the lipid metabolism; hence, it may be recommended for consumption by the general population.

Evaluation of the ultrasound influence in the cutaneous penetration of d-panthenol: test in vitro.

BACKGROUND: d-panthenol is a popular additive in cosmetic and pharmaceutical preparations. However, in order for this vitamin to provide skin benefits, it must penetrate the stratum corneum. OBJECTIVE: To verify the penetrability of d-panthenol in the skin and evaluate the effect of ultrasound on the cutaneous penetration of this vitamin. METHODS: The diffusion cell technique with pig skin as the membrane, distilled water as the receptor solution, and a hydrophilic d-panthenol gel were used for the research. The experimental groups were gel + d-panthenol (10%) and gel + d-panthenol (10%) + ultrasound. The receptor solution was collected at predetermined times and the amount of d-panthenol was determined by using a spectrophotometer at 406 nm. RESULTS: Ultrasound resulted in a statistically significant increase (P < 0.05) in the penetration of d-panthenol at 2, 60, and 240 min. CONCLUSION: d-panthenol penetration through the pig's skin is enhanced through the use of ultrasound.

Efeito do ultra-som na permeacao cutanea do tiratricol: analise histologica / Effect of ultrasound on the tiratricol skin permeation: histologic analysis

O objetivo deste trabalho foi estudar o efeito do ultra-som na permeacao cutanea do tiratricol, farmacio lipolitico muito utilizado no tratamento mesoterapico para celulite. Trata-se, porem, de metodo invasivo, razao do interesse pela aplicacao topica. Os tratamentos topicos foram realizados no dorso de cinco suinos(Landrace x Large White), machos, com 50 dias, em areas de 8cm :C-controle, G-gel (carbpol 940), G+US-gel +ultra-som, G+T-gel+tiratricol (20mg/3 de gel), G+T+US-gel+tiratricol+ultra-som, e M- mesoterapia, tratados diariamente por 15 dias. O protocolo do US foi: 3 MHz, 0,2 W/cm, continuo. Apos processamento histologico em parafina com coloracao por HE, usando-se ocular milimetrada (Zeiss), forma feitas medidas histometricas da pele, analisadas pela (ANOVA) com teste de DUNNET a 5(por cento) (p>,0,05) de significancia. Essa analise mostrou espessamento na epiderme, em razao do poder hidratente do gel, o que nao ocorreu no tratamento com mesoterapia. A hipoderme das areas tratadas por mesoterapia sofreu reducao significativa em sua espessura (33,8(por cento), p<0,05), assim como as areas tratadas por gel + tiratricol + US (23,5 (por cento), p<0,05), o que nao ocorreu com o tiratricol isoladamente (6,08 por cento, p>0,05). Concluiu-se que o US aumentou a permeacao do tiratricol

Beneficial effect of goat milk on bioavailability of copper, zinc and selenium in rats.

We studied the effects of dietary inclusion of freeze-dried goat and cow milk on the utilization of copper, zinc and selenium, and on the metabolic fate of copper and zinc, in rats using a standard (non-milk) control diet recommended by the American Institute of Nutrition and diets based on goat or cow milk. For animals given the goat milk diet, the apparent digestibility coefficient (ADC) of copper is similar to that obtained with the standard diet and higher than that in animals given the cow milk diet. The copper balance was higher among the rats given the goat milk and the standard diets than among those given cow milk. The ADC and retention of zinc and selenium were higher for the goat milk diet than for the other two diets. The copper content in the kidneys and in the femur was greater when the animals consumed a goat milk diet than a cow milk diet. Zn deposits in femur, testes, liver, kidney, heart and longissimus dorsi muscle were greatest with the goat-milk diet, followed by the standard diet and were lowest for the rats given cow-milk diet. This study shows that the goat-milk has an important and beneficial effect on the bioavailability of copper, zinc and selenium.

Study of nutritive utilization of protein and magnesium in rats with resection of the distal small intestine. Beneficial effect of goat milk.

The search for diets to improve the nutritive utilization of protein and magnesium in malabsorption syndrome led us to study goat milk, because of its particular nutritional characteristics, and to compare it with cow milk, which is most commonly consumed. We studied the nutritive utilization of protein and magnesium in transected rats (control) and in rats with resection of 50% of the distal small intestine. The diets used were the standard diet recommended by the American Institute of Nutrition and diets based on lyophilized goat or cow milk. The consumption of goat milk produces better protein efficiency ratio and food conversion efficiency values, particularly in rats with intestinal resection, together with a higher nutritive utilization of protein. Magnesium apparent digestibility coefficient is not modified by intestinal resection in rats fed with goat milk-based diet, on the contrary to the standard and cow milk diets. Magnesium apparent digestibility coefficient is greater for the goat milk group, which is reflected in the greater quantity of this mineral stored in bone. These results demonstrate the beneficial effect of goat milk on the nutritive utilization of protein and on magnesium bioavailability, especially in animals with resection of the distal small intestine.

Beneficial effect of goat milk on nutritive utilization of iron and copper in malabsorption syndrome.

The search for diets that improve the digestive and metabolic use of iron and copper in malabsorption syndrome led us to study goat milk for particular nutritional characteristics and compare it with cow milk, which is usually supplied. We studied the metabolism of iron and copper in transected rats (control) and in resected rats (resection of 50% of the distal small intestine). The diets used were the standard diet recommended by the American Institute of Nutrition and diets based on goat or cow milk. Intestinal resection reduced the apparent digestibility coefficient (ADC) of iron in the three diets tested. In the transected and resected rats, the ADC of iron was highest with the goat milk diet, followed by the standard diet and lowest with the cow milk diet. The ADC of copper was not affected by intestinal resection in the animals fed the goat milk diet, and was higher than that in the two groups of animals fed the other diets. Intestinal resection reduced the ADC of copper with the standard diet and the cow milk diet. When both groups of animals were fed the goat milk diet, the deposit of iron in the organs was greater than with those fed the cow milk diet and similar to that in those animals given the standard diet. The copper content in the kidneys was lower in the resected than in the transected animals, except in the case of those fed the goat milk diet, in which it was similar to that of the control (transected) rats. This study shows the beneficial effect of goat milk, with respect to cow milk, on the metabolism of iron and copper in control rats, especially those with malabsorption syndrome.

[Affective disorders: analysis of their comorbidity in the more frequent psychiatric disorders]. / Trastornos afectivos: análisis de su comorbilidad en los trastornos psiquiátricos más frecuentes.

Comorbidity is defined as the presence of two or more independent diseases in the same subject. This paper reviews the comorbidity of affective disorders with other mental disorders. We focus on the disorders of anxiety, schizophrenia, dependence on psychoactive substances, eating disorders, personality disorders and obsessive-compulsive disorder. To this end, we have carried out an extensive review that has taken account of numerous studies, as well as of different diagnostic orientations (categorical or dimensional). In general the presence of affective symptoms and/or disorders in the context of other mental pathologies is high. Moreover, comorbidity has a high transcendence with respect to clinical prognosis (worse response to treatments, greater symptomatic persistence, greater tendency to chronicity and greater risk of mortality) and the social consequences (decline in work performance and greater use of resources). Nonetheless, we must bear in mind that the analysis of the comorbidity of affective disorders in other mental disorders is complex and controversial, not only because of its high frequency, but also because of the existence of symptomatic overlap, scarcity of signs and pathognomonic symptoms, variability of diagnostic criteria, applied methodological differences, as well as a scarcity of longitudinal and prospective studies.

Digestive utilization of goat and cow milk fat in malabsorption syndrome.

We studied the effects of goat and cow milk fat on the digestive utilization of this nutrient and on some of the biochemical parameters that are related to the metabolisim of lipids, using rats with a resection of 50% of the distal small intestine and control animals (transected). The fat content in all the diets was 10% but the lipid quality was varied: the standard diet was based on olive oil, while the other two diets included fat obtained from lyophilized goat milk and cow milk, respectively. The digestive utilization of the fat was lower in the resected animals than in the transected ones for all three diets studied. In both resected and transected animals. the apparent digestibility coefficient (ADC) of the fat was greater with the standard diet (olive oil) than with diets whose fat content was provided by goat or cow milk. The digestive utilization of the fat was greater in the transected and resected rats receiving a diet of goat's milk (rich in medium-chain triglycerides) than those given a cow-milk-based diet and more closely approached the values obtained for olive oil. The consumption of goat milk reduced levels of cholesterol while levels of triglycerides, HDL, GOT and GPT remained with in the normal ranges, for both transected and resected animals. The advantageous effect of goat milk on the metabolisim of lipids with respect to cow milk suggests that the former should be included in the diet in eases of malabsorption snydrome.

[Assessment of auditory behaviour and neuropsychomotor development of low weight infants]. / Avaliação do comportamento auditivo e neuropsicomotor em lactentes de baixo peso ao nascimento.

UNLABELLED: PURPOSES AND METHODS: The aims of this study were: to detect moderate to profound hearing loss in high risk infants for deafness, to follow up their auditory development (localization of the sound source- Hear Kit - Downs, 1984); and their neuropsychomotor development during the two first years of life. All subjects were submitted to cerebral ultra sound assessment. RESULTS: An infant with a suspected hearing loss was identified and nine infants presented neuropsychomotor development delay. In a transversal analysis of the hearing assessment data it was verified that infants in this study presented different response than the referred in the American literature. CONCLUSIONS: It was concluded that 5% of the infants were delayed in localizing the sound source. Medical peech and hearing follow up during the two first years of life of high risk infants for deafness is important and advisable.

Effect of epithelial debridement on human cornea proteoglycans.

Corneal transparency is attributed to the regular spacing and diameter of collagen fibrils, and proteoglycans may play a role in fibrillogenesis and matrix assembly. Corneal scar tissue is opaque and this opacity is explained by decreased ultrastructural order that may be related to proteoglycan composition. Thus, the objectives of the present study were to characterize the proteoglycans synthesized by human corneal explants and to investigate the effect of mechanical epithelial debridement. Human corneas unsuitable for transplants were immersed in F-12 culture medium and maintained under tissue culture conditions. The proteoglycans synthesized in 24 h were labeled metabolically by the addition of (35)S-sulfate to the medium. These compounds were extracted by 4 M GuHCl and identified by a combination of agarose gel electrophoresis, enzymatic degradation with protease and mucopolysaccharidases, and immunoblotting. Decorin was identified as the main dermatan sulfate proteoglycan and keratan sulfate proteoglycans were also prominent components. When the glycosaminoglycan side chains were analyzed, only keratan sulfate and dermatan sulfate were detected (approximately 50% each). Nevertheless, when these compounds were (35)S-labeled metabolically, the label in dermatan sulfate was greater than in keratan sulfate, suggesting a lower synthesis rate for keratan sulfate. (35)S-Heparan sulfate also appeared. The removal of the epithelial layer caused a decrease in heparan sulfate labeling and induced the synthesis of dermatan sulfate by the stroma. The increased deposit of dermatan sulfate proteoglycans in the stroma suggests a functional relationship between epithelium and stroma that could be related to the corneal opacity that may appear after epithelial cell debridement.