RESUMO
BACKGROUND: This study evaluates endoscopic and quality of life (QoL) outcomes in two groups, composed by both allergic (A) and non-allergic (N-A) adolescents undergoing septoplasty with concurrent turbinate surgery by radiofrequency treated after surgery with nasal spray containing liposomes and vitamins A and E. METHODS: This double-blind randomized study was carried out on 40 patients (22 males, 18 females, mean age 15.5±1.0 years) undergoing septoplasty and volumetric tissue reduction of inferior turbinates by radiofrequency for post-traumatic deformities and severe nasal obstruction. We enrolled 20 subjects with positive skin prick tests and 20 with negative skin prick tests (SPT) to aeroallergens. All subjects underwent the Visual Analogue Scale (VAS) questionnaire and the nasal endoscopy score by Lund and Kennedy (LK) at baseline before surgery (T0) and 15 days (T15) and 21 days (T21) after treatment. After surgery, the nose was not packed and the day after surgery all subjects were randomized into two groups, experimental arm group I (GI) and control arm group II (GII) and given the treatment, nasal spray containing liposomes composed of phospholipids, fatty acids, and vitamin A and E for group I and saline solution (sodium chloride 0.9%) for group II. RESULTS: After therapy, the VAS and LK scores were better (P<0.05) in the investigational than in the control arm in both sub-groups (A and N-A). CONCLUSIONS: Our findings suggested that liposomal, vitamins A and E nasal spray improves the QoL in the early postoperative period, both in A and N-A sub-groups.
Assuntos
Septo Nasal/cirurgia , Rinoplastia/métodos , Conchas Nasais/cirurgia , Vitamina A/administração & dosagem , Vitamina E/administração & dosagem , Adolescente , Método Duplo-Cego , Endoscopia , Feminino , Humanos , Hipersensibilidade/diagnóstico , Hipersensibilidade/imunologia , Lipossomos , Masculino , Obstrução Nasal/cirurgia , Sprays Nasais , Fosfolipídeos/administração & dosagem , Qualidade de Vida , Inquéritos e Questionários , Fatores de Tempo , Resultado do TratamentoRESUMO
The increasing need for biodegradable polymers demands efficient and environmentally friendly extraction methods. In this study, a simple and sustainable method for extracting polyhydroxybutyrate (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate (PHB-co-HV) from Methylocystis hirsuta and a mixed methanotrophic consortium with different biopolymer contents was presented. The extraction of biopolymers with 1,3-dioxolane was initially investigated by varying the biomass-to-solvent ratio (i.e., 1:2 w v-1, 1:4 w v-1, 1:6 w v-1, 1:8 w v-1 and 1:10 w v-1) and extraction time (6, 8 and 10 h) at the boiling point of the solvent and atmospheric pressure. Based on the results of the preliminary tests, and only for the most efficient biomass-to-solvent ratio, the extraction kinetics were also studied over a time interval ranging from 30 min to 6 h. For Methylocystis hirsuta, the investigation of the extraction time showed that the maximum extraction was reached after 30 min, with recovery yields of 87% and 75% and purities of 98.7% and 94% for PHB and PHB-co-HV, respectively. Similarly, the extraction of PHB and PHB-co-HV from a mixed methanotrophic strain yielded 88% w w-1 and 70% w w-1 recovery, respectively, with 98% w w-1 purity, at a biomass-to-solvent ratio of 6 in 30 min.
RESUMO
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) is a biobased and biodegradable polymer that could efficiently replace fossil-based plastics. However, its widespread deployment is slowed down by the high production cost. In this work, the techno-economic assessment of the process for producing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from low-cost substrates, such as methane and valeric acid derived from the anaerobic digestion of organic wastes, is proposed. Several strategies for cost abatement, such as the use of a mixed consortium and a line for reagent recycling during downstream, were adopted. Different scenarios in terms of production, from 100 to 100,000 t/y, were analysed, and, for each case, the effect of the reactor volume (small, medium and large size) on the selling price was assessed. In addition, the effect of biomass concentration was also considered. Results show that the selling price of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) is minimum for a production plant with 100,000 t/y capacity, accounting for 18.4 /kg, and highly influenced by the biomass concentration since it can be reduced up to 8.6 /kg by increasing the total suspended solids from 5 to 30 g/L, This adjustment aligns the breakeven point of PHBV with the reported average commercial price.
Assuntos
Biomassa , Reatores Biológicos , Ácidos Graxos Voláteis , Metano , Poliésteres , Poli-Hidroxibutiratos , Metano/análise , Ácidos Graxos Voláteis/análise , BiopolímerosRESUMO
Due to their excellent properties, polyhydroxyalkanoates are gaining increasing recognition in the biodegradable polymer market. These biogenic polyesters are characterized by high biodegradability in multiple environments, overcoming the limitation of composting plants only and their versatility in production. The most consolidated techniques in the literature or the reference legislation for the physical, chemical and mechanical characterisation of the final product are reported since its usability on the market is still linked to its quality, including the biodegradability certificate. This versatility makes polyhydroxyalkanoates a promising prospect with the potential to replace fossil-based thermoplastics sustainably. This review analyses and compares the physical, chemical and mechanical properties of poly-ß-hydroxybutyrate and poly-ß-hydroxybutyrate-co-ß-hydroxyvalerate, indicating their current limitations and strengths. In particular, the copolymer is characterised by better performance in terms of crystallinity, hardness and workability. However, the knowledge in this area is still in its infancy, and the selling prices are too high (9-18 $ kg-1). An analysis of the main extraction techniques, established and in development, is also included. Solvent extraction is currently the most widely used method due to its efficiency and final product quality. In this context, the extraction phase of the biopolymer production process remains a major challenge due to its high costs and the need to use non-halogenated toxic solvents to improve the production of good-quality bioplastics. The review also discusses all fundamental parameters for optimising the process, such as solubility and temperature.
Assuntos
Biodegradação Ambiental , Poliésteres , Poli-Hidroxialcanoatos , Poli-Hidroxibutiratos , Poliésteres/química , Solventes/química , Hidroxibutiratos/químicaRESUMO
Polyhydroxyalkanoates (PHAs) are biobased and biodegradable polymers that could effectively replace fossil-based and non-biodegradable plastics. However, their production is currently limited by the high production costs, mainly due to the costly carbon sources used, low productivity and quality of the materials produced. A potential solution lies in utilizing cheap and renewable carbon sources as the primary feedstock during the biological production of PHAs, paving the way for a completely sustainable and economically viable process. In this review, the opportunities and challenges related to the production of polyhydroxyalkanoates using methane and volatile fatty acids (VFAs) as substrates were explored, with a focus on poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate). The discussion reports the current knowledge about promising Type II methanotrophs, the impact of process parameters such as limiting nutrients, CH4:O2 ratio and temperature, the type of co-substrate and its concentration. Additionally, the strategies developed until now to enhance PHA production yields were also discussed.
RESUMO
In this work, the potential of a synthetic coculture and a mixed methanotrophic consortium to synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from renewable and waste-based feedstocks was assessed batchwise. Methylocystis parvuscocultivated with Rhodococcus opacus and a Methylocystis-enriched culture previously grown on methane were subjected to nutrient starvation in a medium enriched with valeric acid (30% w w-1 of Ctot) or with a VFAs mixture containing acetic, propionic, butyric, and valeric acids (15% w w-1 of Ctot) under a CH4:O2 or air atmosphere. For all test series, pH was adjusted to 7 after adding the cosubstrates, and a negligible substrate consumption or polymer production was considered the end point of the trial. Results showed that valeric acid promoted PHBV accumulation in both cultures regardless of the atmosphere. Interestingly, the mixture of VFAs supported PHBV accumulation only in the presence of methane. The highest PHBV contents for the coculture and the mixed consortium, equal to 73.7 ± 2.5% w w-1 and 49.6 ± 13% w w-1, respectively, were obtained with methane and the VFAs mixture. This study demonstrates the suitability of cocultures and biobased cosubstrates for the sustainable production of the biodegradable polymer PHBV.
RESUMO
In this work, the potential of Methylocystis hirsuta to simultaneously use methane and volatile fatty acids mixtures for triggering PHBV accumulation was assessed for the first time batchwise. Biotic controls carried out with CH4 alone confirmed the inability of Methylocystis hirsuta to produce PHBV and achieved 71.2 ± 7 g m-3d-1 of PHB. Pure valeric acid and two synthetic mixtures simulating VFAs effluents from the anaerobic digestion of food waste at 35 °C (M1) and 55 °C (M2) were supplied to promote 3-HV inclusion. Results showed that pure valeric acid supported the highest polymer yields of 105.8 ± 9 g m-3d-1 (3-HB:3-HV=70:30). M1 mixtures led to a maximum of 103 ± 4 g m-3d-1 of PHBV (3-HB:3-HV=85:15), while M2 mixtures, which did not include valeric acid, showed no PHV synthesis. This suggested that the synthesis of PHBV from VFAs effluents depends on the composition of the mixtures, which can be tuned during the anaerobic digestion process.
Assuntos
Metano , Eliminação de Resíduos , Alimentos , Ácidos Graxos Voláteis , Hidroxibutiratos , Poli-HidroxibutiratosRESUMO
Orally transmitted Chagas disease (ChD), which is a well-known entity in the Brazilian Amazon Region, was first documented in Venezuela in December 2007, when 103 people attending an urban public school in Caracas became infected by ingesting juice that was contaminated with Trypanosoma cruzi. The infection occurred 45-50 days prior to the initiation of the sampling performed in the current study. Parasitological methods were used to diagnose the first nine symptomatic patients; T. cruzi was found in all of them. However, because this outbreak was managed as a sudden emergency during Christmas time, we needed to rapidly evaluate 1,000 people at risk, so we decided to use conventional serology to detect specific IgM and IgG antibodies via ELISA as well as indirect haemagglutination, which produced positive test results for 9.1%, 11.9% and 9.9% of the individuals tested, respectively. In other more restricted patient groups, polymerase chain reaction (PCR) provided more sensitive results (80.4%) than blood cultures (16.2%) and animal inoculations (11.6%). Although the classical diagnosis of acute ChD is mainly based on parasitological findings, highly sensitive and specific serological techniques can provide rapid results during large and severe outbreaks, as described herein. The use of these serological techniques allows prompt treatment of all individuals suspected of being infected, resulting in reduced rates of morbidity and mortality.
Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/diagnóstico , Surtos de Doenças , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Trypanosoma cruzi/imunologia , Adulto , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Criança , DNA de Protozoário/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Testes de Hemaglutinação , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Venezuela/epidemiologiaRESUMO
The pressing problem posed by plastic pollution has led to other, environmentally friendly alternatives, such as polyhydroxyalkanoates. This work proposes an innovative process to produce poly(3-hydroxybutyrate) by replacing expensive substrates, such as sugars, with methane. A two-step process was simulated: a first fermentation is performed in a continuous mode for 20 days to grow a strain belonging to the genus Methylocystis, while a second semi-continuous and nitrogen-limited fermentation is employed to induce the poly(3-hydroxybutyrate) accumulation within 12 days. The effects of the superficial gas velocity on the mass transfer and the poly(3-hydroxybutyrate) production yields were evaluated. Several scenarios were analyzed to optimize the geometry of the reactors and the methane utilization. The working volume of the reactors, as well as the presence of gas recycling stream, were shown to affect the global yields positively, while improving the aspect ratio from 8 to 19, with equal volume, lowered the fraction of poly(3-hydroxybutyrate) into the biomass by up to 37.5%.
Assuntos
Hidroxibutiratos , Metano , Ácido 3-Hidroxibutírico , Reatores Biológicos , PoliésteresRESUMO
Bacterially produced polyhydroxyalkanoates are valuable substitutes for petrochemical plastics, but their current production capacities are very scarce. Producing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-co-HV) from methane and odd-chain carbon fatty acids could make the production of this biodegradable polymer cost-effective. This study analyzes the main factors affecting methanotrophic growth and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) accumulation, simulating a pilot-scale process based on a double-stage approach. The effects of the nitrogen source and the oxygen partial pressure during a 20 day growth phase were studied; the cosubstrate concentration, the culture selected, and the methane partial pressure were investigated during the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) production stage performed within 15 days under nutrient starvation. Methylocystis parvus OBBP and Methylosinus thricosporum OB3b reached the maximum growth productivities with ammonium as the nitrogen source and oxygen at high partial pressure. The simulation of the PHB-co-HV accumulation revealed that methanotrophs could better accumulate the polymer with low valeric acid concentrations. A methane-abundant gas stream (0.5 atm of methane) could increase process yields up to 0.32 kg m-3 d-1.
RESUMO
BACKGROUND: Deep Neck Infections (DNIs) spread along fascial planes and involve neck spaces. Recently, their incidence has decreased due to the introduction of antibiotics; nevertheless, complications related to DNIs are often life-threatening. OBJECTIVE: The purpose of this article is focused on the identification of predisposing factors of these complications, as well as on the development of a reliable therapeutic algorithm. METHODS: Sixty patients with DNIs were enrolled from 2006 to 2019 for a retrospective study. The exclusion criteria for the present study were cellulitis, small abscesses responding to empiric or specific antibiotic therapy, or involvement of only one deep neck space. During the analysis, the following parameters of interest have been evaluated: gender, age, site of origin, pathways of spread, comorbidities, clinical features, bacteriology data, type of surgical approach required, complications, duration of hospitalization and mortality rate. On admission, microbial swab analysis was performed. RESULTS: Diabetes Mellitus (DM), Chronic Obstructive Pulmonary Disease (COPD), iron deficiency anemia and the involvement of multiple spaces have been associated with a significantly higher risk of developing complications. Most of our patients had polymicrobial infections. All patients underwent surgical drainage. The complication rate had occurred in 56.6% of patients, while death in 18.3%. CONCLUSION: DNIs represent a medical and surgical emergency with potentially serious complications; thus, avoidance of diagnostic delay is mandatory. Our preliminary data suggest the importance of evaluating the extent of infections because the involvement of multiple spaces requires timely surgery due to the higher risk of complications and mortality.
Assuntos
Diagnóstico Tardio , Pescoço , Abscesso/diagnóstico , Abscesso/etiologia , Abscesso/terapia , Algoritmos , Antibacterianos/uso terapêutico , Diagnóstico Tardio/efeitos adversos , Humanos , Pescoço/microbiologia , Pescoço/cirurgia , Estudos RetrospectivosRESUMO
BACKGROUND: Trypanosoma cruzi oral transmission is possible through food contamination by vector's feces. Little is known about the epidemiology and clinical features of microepidemics of orally acquired acute Chagas disease (CD). METHODS: A case-control, cohort-nested, epidemiological study was conducted during an outbreak of acute CD that affected a school community. Structured interviews were designed to identify symptoms and sources of infection. Electrocardiograms were obtained for all patients. Specific serum antibodies were assessed by immunoenzimatic and indirect hemagglutination tests. In some cases, parasitemia was tested directly or by culture, animal inoculation, and/or a polymerase chain reaction technique. RESULTS: Infection was confirmed in 103 of 1000 exposed individuals. Of those infected, 75% were symptomatic, 20.3% required hospitalization, 59% showed ECG abnormalities, parasitemia was documented in 44, and 1 child died. Clinical features differed from those seen in vectorial transmission. The infection rate was significantly higher among younger children. An epidemiological investigation incriminated contaminated fresh guava juice as the sole source of infection. CONCLUSIONS: This outbreak was unique, because it affected a large, urban, predominantly young, middle-class, otherwise healthy population and resulted in an unprecedented public health emergency. Rapid diagnosis and treatment avoided higher lethality. Food-borne transmission of T. cruzi may occur more often than is currently recognized.
Assuntos
Doença de Chagas/epidemiologia , Surtos de Doenças , Adolescente , Fatores Etários , Bebidas/parasitologia , Estudos de Casos e Controles , Doença de Chagas/etiologia , Doença de Chagas/fisiopatologia , Criança , Eletrocardiografia , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/etiologia , Testes de Hemaglutinação , Humanos , Modelos Logísticos , Masculino , Reação em Cadeia da Polimerase , Psidium/parasitologia , Fatores de Risco , Instituições Acadêmicas , Trypanosoma cruzi , População Urbana , Venezuela/epidemiologia , Adulto JovemRESUMO
Laryngectomized patients showed an unconventional response to SARS-CoV-2 viral infection. Here, we describe five different patient cases along with our interpretation of the phenomena and suggestions for their safe management.
RESUMO
Laryngeal cancer (LCa), a neoplasm of the head and neck region, is a leading cause of death worldwide. Surgical intervention remains the mainstay of LCa treatment, but a crucial point is represented by the possible nodal involvement. Therefore, it is urgently needed to develop biomarkers and therapeutic tools able to drive treatment approaches for LCa. In this study, we investigated deregulated microRNAs (miRNAs) in tissues from LCa patients with either lymph node metastases (N+) or not (N-). miRNA expression profiling was performed by a comprehensive PCR array and subsequent validation by RT-qPCR. Results showed a significant decrease of miR-449a expression in N+ compared to N- patients, and miR-133b down-modulation in LCa tissues compared to paired normal ones. Receiver operating characteristic (ROC) curve analysis revealed the potential diagnostic power of miR-133b for LCa detection. According to the validation results, we selected miR-449a for further in vitro studies. Ectopic miR-449a expression in the LCa cell line Hep-2 inhibited invasion and motility in vitro, slowed cell proliferation, and induced the downregulation of Notch1 and Notch2 as direct targets of miR-449a. Collectively, this study provides new promising biomarkers for LCa diagnosis and a new opportunity to use miR-449a for the treatment of nodal metastases in LCa patients.
RESUMO
Adenoid cystic carcinoma (ACC) is a relatively rare tumor that accounts for <1% of all head and neck malignancies. Laryngeal localization of ACC, which is most commonly hypoglottic, is relatively rare, occurring in 0.07-0.25% of all laryngeal tumors. ACC is characterized as a slow-growing tumor with a high recurrence rate, which often causes dyspnea and hoarseness. ACC exhibits a propensity for perineural invasion and thus, patients may experience pain as a late symptom of the disease. Distant metastasis occurs in 35-50% of cases and the lungs are the most common site of metastasis. Tumors are usually diagnosed by physical examination with fiberoscopy and computed tomography of the neck and chest, due to the high rate of lung metastases. The standard therapy for ACC is surgery followed by radiotherapy. In this study, a 70-year-old patient presented with laryngeal ACC, who underwent total laryngectomy with bilateral neck dissection and adjuvant radiotherapy, is presented. Follow-up examination performed 2 years after surgery revealed no evidence of locoregional recurrence or distant metastases. Previously published literature regarding ACC of the larynx was also reviewed.
RESUMO
Basaloid squamous cell carcinoma (BSCC) is a rare, aggressive and distinct variant of squamous cell carcinoma (SCC) of the upper respiratory and digestive tract. We have evaluated disease specific survival (DSS) and overall survival (OS) through Kaplan-Meier method and mortality risk through univariate statistical analysis of Cox in 42 cases of BSCC and other 42 of laryngeal SCC (LSCC) matched for both age and sex. We demonstrated that laryngeal BSCC is a more aggressive tumor than LSCC as is associated to higher nodal recurrence of pathology (5 vs 2 patients, overall risk, OR 2.7), a reduced survival (median survival 34 vs 40 months, OR 3.2 for mortality); in addition, basaloid patients have a higher risk to be affected by second primary tumors (13 vs 3 patients, OR 5.8) and a higher probability to die for this second tumor (Hazard Risk, HR 4.4). The analysis of survival shows an increased mortality risk concurrent with the parameters assessed by univariate analyses that assume a predictive and statistical significance in second tumor and grading in basaloid LSSC.
RESUMO
BACKGROUND AND OBJECTIVES: Hearing impairment (HI) has been previously demonstrated in patients with Parkinson's disease (PD). Pure Tone Audiometry (PTA) gives no information about patients' ability to hear and understand speech. To find out hearing ability and speech discrimination of PD patients, we expanded audiological evaluation by means of speech audiometry (SA). PATIENTS AND METHODS: We screened a series of consecutive PD patients. Severity of motor symptoms and staging were measured by the UPDRS-III and the H&Y scales. Audiometric evaluation consisted of a standardized audiological examination, PTA and SA. Healthy age- and sex-matched subjects were selected as controls. RESULTS: 45 PD patients and 45 healthy controls were enrolled. PTA confirmed our previous finding of high-frequency HI in PD patients. The mean values for the Speech Recognition Threshold were higher in PD patients as compared with controls. PD patients were more likely to have impaired speech discrimination profiles and higher disease stages. Neither the patients nor the controls showed a significant speech-tone dissociation and rollover phenomenon. CONCLUSION: Our results confirmed sensorineural HI in PD patients. Moreover, SA showed impaired speech discrimination abilities in PD patients as compared with control group thus expanding the audiologic findings of PD.
Assuntos
Audiometria de Tons Puros/métodos , Perda Auditiva Neurossensorial/diagnóstico , Doença de Parkinson/diagnóstico , Percepção da Fala/fisiologia , Idoso , Estudos Transversais , Feminino , Perda Auditiva Neurossensorial/epidemiologia , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Doença de Parkinson/fisiopatologiaRESUMO
Oral transmission of Trypanosoma cruzi is a frequent cause of acute Chagas disease (ChD). In the present cross-sectional study, we report the epidemiological, clinical, serological and molecular outcomes of the second largest outbreak of oral ChD described in the literature. It occurred in March 2009 in Chichiriviche de la Costa, a rural seashore community at the central littoral in Venezuela. The vehicle was an artisanal guava juice prepared at the local school and Panstrongylus geniculatus was the vector involved. TcI genotype was isolated from patients and vector; some showed a mixture of haplotypes. Using molecular markers, parasitic loads were high. Eighty-nine cases were diagnosed, the majority (87.5%) in school children 6-15 years of age. Frequency of symptomatic patients was high (89.9%) with long-standing fever in 87.5%; 82.3% had pericardial effusion detected by echocardiogram and 41% had EKG abnormalities. Three children, a pregnant woman and her stillborn child died (5.6% mortality). The community was addressed by simultaneous determination of specific IgG and IgM, confirmed with indirect hemagglutination and lytic antibodies. Determination of IgG and IgA in saliva had low sensitivity. No individual parasitological or serological technique diagnosed 100% of cases. Culture and PCR detected T. cruzi in 95.5% of examined individuals. Based on the increasing incidence of oral acute cases of ChD, it appears that food is becoming one of the most important modes of transmission in the Amazon, Caribbean and Andes regions of America.
RESUMO
Meningioma is a common intracranial tumor involving the meninges. The localization of this type of tumor is rarely extracranial due to its typically low invasive properties. Furthermore, invasion of the middle ear is exceptional. The present study reported a case of meningioma extending into the middle ear from the middle cranial fossa through the tegmen tympani. The clinical and pathological characteristics, as well as the outcome of the patient, were described.
RESUMO
In the present report we describe Trypanosoma cruzi ubiquitin as an antigen to be utilized in the differential diagnosis of Chagas disease and leishmaniasis. Initially, recombinant T. cruzi ubiquitin was evaluated against a panel of sera by phage dot immunoassay, showing a good performance against chagasic sera. However, the presence of a carboxy-terminal tail region encoding a ribosomal protein homologous to a related protein present in the genome of Leishmania sp. gave significant cross-reactivity with leishmanial sera. Therefore, ubiquitin was purified by a simple biochemical protocol and its immunoreactivity was studied by enzyme-linked immunosorbent assay. Analysis of 104 sera indicates that the response to ubiquitin is very sensitive towards chronic chagasic sera (98%) and, more important, highly species-specific, presenting better performance compared to the use of the recombinant protein or the total epimastigote extracts when tested against a panel of leishmanial sera, where out of a total of 70 sera tested, only five sera from the mucocutaneous form of the disease reacted with T. cruzi ubiquitin. On the other hand, Leishmania ubiquitin was not recognized by chagasic sera, but was recognized by sera from different forms of leishmaniasis. These results make ubiquitin an excellent candidate to be used in the differential diagnosis of these two parasitic diseases. The molecular basis for this highly species-specific response is discussed.