[Translated article] Clinical and Histopathologic Features of Subungual Melanoma in 57 Mexican Patients: A 5-Year Cohort Study.

Although subungual melanoma is uncommon, it is associated with worse outcomes than melanomas in other locations and accounts for 1% to 23% of all melanomas, depending on the population. The aim of this study was to describe the clinical and histopathologic features of subungual melanoma in a Mexican population. We identified 303 patients with melanoma, and of these, 19% (57 patients with a median age of 71 years) had subungual melanoma. The main sites affected were the lower limbs (52.6%) and the toe (75.4%). The most common histologic subtype was acral lentiginous melanoma (50.9%). Median Breslow thickness was 3 mm, and stage IA tumors were the most common (in 28.1% of patients). Recurrence and metastasis occurred in 19.3% and 8.8% of patients, respectively. The clinical and histopathologic features identified are similar to those described in the literature. Early diagnosis and treatment are crucial for improving prognosis.

Clinical and Histopathologic Features of Subungual Melanoma in 57 Mexican Patients: A 5-Year Cohort Study. / Características clínicas e histopatológicas de melanoma subungueal en 57 pacientes mexicanos: una cohorte de 5 años.

Although subungual melanoma is uncommon, it is associated with worse outcomes than melanomas in other locations and accounts for 1% to 23% of all melanomas, depending on the population. The aim of this study was to describe the clinical and histopathologic features of subungual melanoma in a Mexican population. We identified 303 patients with melanoma, and of these, 19% (57 patients with a median age of 71 years) had subungual melanoma. The main sites affected were the lower limbs (52.6%) and the toe (75.4%). The most common histologic subtype was acral lentiginous melanoma (50.9%). Median Breslow thickness was 3 mm, and stage IA tumors were the most common (in 28.1% of patients). Recurrence and metastasis occurred in 19.3% and 8.8% of patients, respectively. The clinical and histopathologic features identified are similar to those described in the literature. Early diagnosis and treatment are crucial for improving prognosis.

Clinical, molecular, and immune correlates of the Immunotherapy Response Score in patients with advanced urothelial carcinoma under atezolizumab monotherapy: analysis of the phase II IMvigor210 trial.

BACKGROUND: In the advanced urothelial carcinoma (aUC) scenario there are no consistent immune checkpoint blockade predictive biomarkers. Recently a novel pan-tumor molecular tissue-based biomarker, the Immunotherapy Response Score (IRS), has been proposed. We conducted a retrospective study to validate the prognostic/predictive utility of the IRS in patients with aUC under atezolizumab monotherapy and to characterize its underlying molecular/immune features in the context of the IMvigor210 phase II trial. PATIENTS AND METHODS: This is a post hoc pooled analysis of 261 patients with available clinical, molecular, and immune tumor data treated with atezolizumab monotherapy in the IMvigor210 phase II clinical trial. Efficacy endpoints were overall survival (OS), disease control rate (DCR), and overall response rate (ORR). Survival estimates were calculated by the Kaplan-Meier method, and groups were compared with the log-rank test. The Cox proportional hazards regression model was used to evaluate factors independently associated with OS. Factors associated with disease control (DC) and response were tested with logistic regression in univariable and multivariable analyses. Comparisons between patient and disease characteristics were carried out using chi-square or Fisher's exact tests. All P values were two-sided, and those <0.05 were considered statistically significant. RESULTS: High IRS was significantly associated with a better OS in univariable [hazard ratio (HR) = 0.49, P < 0.001] and multivariable (HR = 0.60, P = 0.018) analyses. DCR and ORR were significantly higher among high IRS patients (DCR for high IRS versus low IRS patients: 57% versus 32%, P < 0.001; ORR: 42% versus 10%, P < 0.001). High IRS patients presented a higher probability of DC and response in univariable [DC: odds ratio (OR) = 2.72, P < 0.001; response: OR = 3.92, P < 0.001] and multivariable (DC: OR = 2.72, P < 0.001; response: OR = 3.92, P < 0.001) analyses. CONCLUSIONS: This study validates IRS as a strong independent prognostic and predictive biomarker for OS and DC/response in patients with aUC treated with atezolizumab monotherapy in the IMvigor210 phase II clinical trial.

Preoperative oral practices and incidence of postoperative complications in hospital medical-surgical procedures: A meta-analysis.

BACKGROUND:  Oral decay prior to a hospital medical-surgical procedure is a risk factor for the development of postoperative complications. However, perioperative oral practices as a protective factor have not been studied. This review aims to evaluate the effectiveness of perioperative oral practices in the reduction of risk of developing postoperative complications in in-hospital medical surgical procedures. MATERIAL AND METHODS: This review and meta-analysis was conducted according to Cochrane guidelines. Medline, Scopus, Scielo, and Cochrane were consulted. Articles of the previous 10 years concerning adult patients undergoing perioperative oral practices prior to hospital medical-surgical procedures, were included. Data of the type of perioperative oral practice, type of postoperative complication and measures of effect on the development of complications were extracted. RESULTS: Of a pool of 1470 articles, 13 were included for systematic review and 10 for meta-analysis. The most common perioperative oral procedures were focalized approach (FA), referred to only the elimination of infectious foci in the oral cavity and comprehensive approach (CA), referred to a integral approach of the patient's oral health, both of which were mainly performed in oncologic surgeries, both were effective in the reduction of postoperative complications (RR=0.48, [95% CI 0.36 - 0.63]). The most reported postoperative complication was postoperative pneumonia. CONCLUSIONS: Perioperative oral management proved to be a protective factor against the development of postoperative complications.

Experience and Utility of the Protocol Kidney Biopsy in the First Year of Kidney Transplantation.

BACKGROUND: Protocol kidney biopsy (PKB) in kidney transplant is a useful tool for graft monitoring because the subclinical detection of histologic lesions helps to modulate immunosuppression. We analyze our experience. METHODS: We performed a descriptive study that analyzed the PKB results at the fourth to sixth month and the first year post transplant of patients with kidney transplant followed in our hospital between January 2015 and June 2021. RESULTS: A total of 100 patients and 134 biopsy results were included, of which 71 were obtained between the fourth and sixth month and 63 at the first year. The mean age was 57.8 years, and 66% were men. Unknown etiology was the most common underlying kidney disease (31%), followed by diabetes mellitus (15%) and polycystic kidney disease (14%). A total of 80% had panel-reactive antibody < 50%. Induction therapy consisted of thymoglobulin (51%) and basiliximab (49%), and maintenance therapy consisted of corticosteroids and tacrolimus (100%), mycophenolate mofetil (82%), and mammalian target of rapamycin inhibitor (18%). Of the total of the PKB results (n = 134), 19 episodes of subclinical rejection (14%) and 10 with borderline changes (7.4%) were observed. Regarding other findings, there were cases of nephrocalcinosis (4.4%), immunoglobulin A nephropathy (2.2%), and BK nephropathy (1.5%). The PKB brought about a change in the therapeutic attitude in 45 cases (33%) of the total number of biopsies, the most frequent change being the administration of boluses of methylprednisolone (12.6%) and the change to mammalian target of rapamycin inhibitor (8.9%). CONCLUSIONS: In our experience, PKB is a useful tool for monitoring and evaluating histologic changes without clinical expression in the kidney graft, allowing us to adapt the treatment during the first year of kidney transplant.

Comparative analysis of the expression of metalloproteases (MMP-2, MMP-9, MMP-11 and MMP-13) and the tissue inhibitor of metalloprotease 3 (TIMP-3) between previous negative biopsies and radical prostatectomies. / Análisis comparativo de la expresión de metaloproteasas (MMP-2, MMP-9, MMP-11 y MMP-13) y del inhibidor tisular de la metaloproteasa 3 (TIMP-3) entre las biopsias previas negativas y las prostatectomías radicales.

Metalloproteases (MMPs) and tissue inhibitor of metalloprotease-3 (TIMP-3) have been associated to the risk of having cancer and tumor aggressiveness. When facing the difficulties of prostate cancer diagnosis, the expression of MMPs and TIMP-3 in negative biopsies could be helpful to evaluate a diagnostic suspicion. Our objective is to carry out a comparative study of the expression of MMPs and TIMP-3 in previous negative biopsies and radical prostatectomies (RP). MATERIAL AND METHODS: Retrospective analysis of a hospital-based cohort including 21 patients with suspicion of prostate carcinoma, whose expressions of MMP-2, 9, 11 and 13 and TIMP-3 were evaluated by immunohistochemistry in the tumor area from previous negative biopsies and RP. RESULTS: Immunohistochemical staining values (Score) for MMPs (-11 and -13) and TIMP-3 showed no significant differences when comparing the areas of negative biopsies where tumors subsequently developed with those of the RP. However, we did observe a significant difference in the increased expression of MMP-2 (P=.002) and MMP-9 (P=.001) in the tumor area of the RP with respect to the corresponding area of the previous negative biopsy. CONCLUSIONS: Our data indicate a higher overall expression of MMP-2 and MMP-9 in the tumor area of the RP compared to the corresponding areas of the negative previous biopsy, which seems to be associated to the process of malignant transformation.

Advanced-stage mycosis fungoides: role of the signal transducer and activator of transcription 3, nuclear factor-κB and nuclear factor of activated T cells pathways.

BACKGROUND: The malignant mechanisms that control the development of cutaneous T-cell lymphoma (CTCL) are beginning to be identified. Recent evidence suggests that disturbances in specific intracellular signalling pathways, such as RAS-mitogen-activated protein kinase, T-cell receptor (TCR)-phospholipase C gamma 1 (PLCG1)-nuclear factor of activated T cells (NFAT) and Janus kinase (JAK)-signal transducer and activator of transcription (STAT), may play an essential role in the pathogenesis of CTCL. OBJECTIVES: To investigate the mechanisms controlling disease development and progression in mycosis fungoides (MF), the most common form of CTCL. METHODS: We collected 100 samples that were submitted for diagnosis of, or a second opinion regarding, MF between 2001 and 2018, 80% of which were in the early clinical stages of the disease. Formalin-fixed paraffin-embedded tissues were used for histological review and to measure the expression by immunohistochemistry of surrogate markers of activation of the TCR-PLCG1-NFAT, JAK-STAT and NF-κB pathways. Folliculotropism and large-cell transformation were also examined. RESULTS: NFAT and nuclear factor kappa B (NF-κB) markers showed a comparable activation status in early and advanced stages, while STAT3 activation was more frequent in advanced stages and was associated with large-cell transformation. Consistently with this observation, STAT3 activation occurred in parallel with MF progression in two initially MF-negative cases. A significant association of NFAT with NF-κB markers was also found, reflecting a common mechanism of activation in the two pathways. Genomic studies identified nine mutations in seven genes known to play a potential role in tumorigenesis in T-cell leukaemia/lymphoma, including PLCG1, JAK3 and STAT3, which underlies the activation of these key cell-survival pathways. A higher mutational allele frequency was detected in advanced stages. CONCLUSIONS: Our results show that STAT3 is activated in advanced cases and is associated with large-cell transformation, while the activation of NFAT and NF-κB is maintained throughout the disease. These findings could have important diagnostic and therapeutic implications. What's already known about this topic? Mycosis fungoides is characterized by a clonal expansion of T cells in the skin. The mechanisms controlling disease development and progression are not fully understood. What does this study add? An association of the nuclear factor of activated T cells and nuclear factor kappa B pathways was found, which could reflect a common mechanism of activation. These pathways were activated in early and advanced stages at the same level. Signal transducer and activator of transcription 3 activation was associated with large-cell transformation and was more frequent in advanced stages. A genomic analysis of cutaneous T-cell lymphoma-associated genes was performed. Nine mutations were detected. What is the translational message? These results could have important implications for the treatment of MF in the near future.

Characterization of the European Sea Bass (Dicentrarchus labrax) Gonadal Transcriptome During Sexual Development.

The European sea bass is one of the most important cultured fish in Europe and has a marked sexual growth dimorphism in favor of females. It is a gonochoristic species with polygenic sex determination, where a combination between still undifferentiated genetic factors and environmental temperature determines sex ratios. The molecular mechanisms responsible for gonadal sex differentiation are still unknown. Here, we sampled fish during the gonadal developmental period (110 to 350 days post fertilization, dpf), and performed a comprehensive transcriptomic study by using a species-specific microarray. This analysis uncovered sex-specific gonadal transcriptomic profiles at each stage of development, identifying larger number of differentially expressed genes in ovaries when compared to testis. The expression patterns of 54 reproduction-related genes were analyzed. We found that hsd17ß10 is a reliable marker of early ovarian differentiation. Further, three genes, pdgfb, snx1, and nfy, not previously related to fish sex differentiation, were tightly associated with testis development in the sea bass. Regarding signaling pathways, lysine degradation, bladder cancer, and NOD-like receptor signaling were enriched for ovarian development while eight pathways including basal transcription factors and steroid biosynthesis were enriched for testis development. Analysis of the transcription factor abundance showed an earlier increase in females than in males. Our results show that, although many players in the sex differentiation pathways are conserved among species, there are peculiarities in gene expression worth exploring. The genes identified in this study illustrate the diversity of players involved in fish sex differentiation and can become potential biomarkers for the management of sex ratios in the European sea bass and perhaps other cultured species.

Neuroprotective effects of phytochemicals on dopaminergic neuron cultures. / Efecto neuroprotector de fitoquímicos en cultivo de neuronas dopaminérgicas.

INTRODUCTION: Parkinson's disease is a progressive neurodegenerative disorder characterised by a loss of dopaminergic neurons in the substantia nigra pars compacta, which results in a significant decrease in dopamine levels and consequent functional motor impairment. DEVELOPMENT: Although its aetiology is not fully understood, several pathogenic mechanisms, including oxidative stress, have been proposed. Current therapeutic approaches are based on dopamine replacement drugs; these agents, however, are not able to stop or even slow disease progression. Novel therapeutic approaches aimed at acting on the pathways leading to neuronal dysfunction and death are under investigation. CONCLUSIONS: In recent years, such natural molecules as polyphenols, alkaloids, and saponins have been shown to have a neuroprotective effect due to their antioxidant and anti-inflammatory properties. The aim of our review is to analyse the most relevant studies worldwide addressing the benefits of some phytochemicals used in in vitro models of Parkinson's disease.

Real-world data on the efficacy and safety of weekly oral vinorelbine in breast cancer patients previously treated with anthracycline or taxane-based regimens.

PURPOSE: To evaluate the efficacy and safety of oral weekly vinorelbine 60 mg/m2 for metastatic breast cancer (MBC) in patients previously treated with anthracyclines or taxanes in routine clinical practice. MATERIALS AND METHODS: Fifty-five patients were enrolled in a prospective multicentre study conducted in Spain. Women ≥ 18 years of age with locally advanced breast cancer who were not candidates for surgical treatment with a radical intention or patients with stage IV disease, and who had received a prior taxane or anthracycline regimen were eligible for participation. RESULTS: Median age was 67 years. Median progression-free survival was 3.7 months (95% CI 2.5-4.9), median overall survival 10 months (95% CI 6.6-13.5), and overall response rate and clinical benefit rate were 29.1% and 49.1%, respectively. Main grade 3 and 4 toxicities were neutropenia 9.1%, febrile neutropenia 3.6% and constipation 3.6%. In total, 86% of the patients received complete treatment without delays or dose reduction. Moreover, HER2-positive patients who received oral vinorelbine concomitantly with trastuzumab showed better response (complete response: HER2-positive 14.3% vs. HER2-negative 0%; partial response: HER2-positive 42.9% vs. HER2-negative 25.6%; p = 0.008), better disease control rate (HER2-positive 100% vs. HER2-negative 46.2%; p = 0.011), and better values for the remaining analysed variables than HER2-negative patients. CONCLUSION: Our study provides real-world data on the use of oral weekly vinorelbine, which proves an effective and well-tolerated regimen for MBC patients previously treated with taxanes or anthracyclines. Patients with HER2-positive disease could also benefit from this treatment in combination with trastuzumab.

A case of unusual histiocytic colitis in a chronic alcoholic obese patient with ankylosing spondylitis.

A 64 year-old Caucasian man was first investigated 21 years ago for persistent diarrhoea. A colonoscopy revealed an erosive pancolitis with unusual vacuolated macrophages. Characteristics of ulcerative colitis or Crohn's disease were absent. Similar findings were observed consistently over the following years. A treatment with Sulfasalazine, Methotrexate or Budesonide was efficient. Histiocytic colitis is rare, and the various causes and different diagnoses are reviewed. The cause for the chronic pancolitis in this obese chronic alcoholic remains unknown at the time of writing. Links to the dyslipidaemia and chronic ankylosing spondylitis presented by the patient are possible hypotheses worth investigating further.

Decanethiol functionalized silver nanoparticles are new powerful leishmanicidals in vitro.

We evaluated, for the first time, the leishmanicidal potential of decanethiol functionalized silver nanoparticles (AgNps-SCH) on promastigotes and amastigotes of different strains and species of Leishmania: L. mexicana and L. major isolated from different patients suffering from localized cutaneous leishmaniasis (CL) and L. mexicana isolated from a patient suffering from diffuse cutaneous leishmaniasis (DCL). We recorded the kinetics of promastigote growth by daily parasite counting for 5 days, promastigote mobility, parasite reproduction by CFSE staining's protocol and promastigote killing using the propidium iodide assay. We also recorded IC50's of promastigotes and amastigotes, therapeutic index, and cytotoxicity by co-culturing macrophages with AgNps-SCH or sodium stibogluconate (Sb) used as reference drug. We used Sb as a reference drug since it is used as the first line treatment for all different types of leishmaniasis. At concentrations 10,000 times lower than those used with Sb, AgNps-SCH had a remarkable leishmanicidal effect in all tested strains of parasites and there was no toxicity to J774A.1 macrophages since > 85% were viable at the concentrations used. Therapeutic index was about 20,000 fold greater than the corresponding one for Sb treated cells. AgNps-SCH inhibited > 80% promastigote proliferation in all tested parasites. These results demonstrate there is a high leishmanicidal potential of AgNps-SCH at concentrations of 0.04 µM. Although more studies are needed, including in vivo testing of AgNps-SCH against different types of leishmaniasis, they can be considered a potential new treatment alternative.

Preoperative factors associated with technical difficulties of laparoscopic cholecystectomy in acute cholecystitis. / Factores prequirúrgicos asociados con dificultades técnicas de la colecistectomía laparoscópica en la colecistitis aguda.

OBJECTIVE: To identify preoperative factors associated with surgical time and conversion of the laparoscopic cholecystectomy (LC) to open surgery in subjects with acute cholecystitis (AC). METHOD: We developed a cross-sectional study that included 99 subjects older than 17 years with definitive diagnosis of AC who had undergone to LC. Preoperative variables such as clinical data, laboratory markers and ultrasound findings as wall thickness, the size of the major calculus and the presence of: perivesicular fluid, multiple cholelithiasis, biliary mud or microlithiasis were registered. We consider indirect measures of technical difficulties of LC the total surgical time and the need for conversion to open surgery. We used the square chi and Mann-Whitney U test to stablish the correlation between preoperative variables and the technical difficulties of LC. We build ROC curves of the variables with significant statistical association (p ≤0.05 and 95% confidence interval [95%CI]) to determine the cut-off points of better sensitivity and specificity to predict conversion of LC to open surgery. RESULTS: A gallbladder wall thickness ≥6mm detected by ultrasound has a sensitivity of 87.5% and a specificity of 62.6% with OR 11.71 (95%CI: 1.38-99; p = 0.008) for predict conversion to open surgery. There was no relationship between surgical time and the preoperative evaluated variables. CONCLUSION: The gallbladder wall thickness detected by the ultrasound is associated with the need of conversion of LC to open surgery in subjects with AC, furthermore this finding could warn the surgeon on the complexity with a particular patient.

First report of linezolid dependence in methicillin-resistant Staphylococcus aureus.

Linezolid is used to treat infections caused by methicillin-resistant Staphylococcus aureus (MRSA). We describe the first report of linezolid dependence in MRSA. The strain was isolated from a respiratory sample of a cystic fibrosis patient, and it showed a thymidine-dependent small-colony variant phenotype. The effect was not related to any known mechanisms implicated in S. aureus resistance to linezolid. The clinical significance of this phenomenon needs further investigation.

Comparison between transthoracic lung ultrasound and a clinical method in confirming the position of double-lumen tube in thoracic anaesthesia. A pilot study.

OBJECTIVE: To compare the ability of lung ultrasound and a clinical method in the confirmation of a selective bronchial intubation by left double-lumen tube in elective thoracic surgery. MATERIAL AND METHODS: A prospective and blind, observational study was conducted in the setting of a university hospital operating room assigned for thoracic surgery. A single group of 105 consecutive patients from a total of 130, were included. After blind intubation, the position of the tube was confirmed by clinical and ultrasound assessment. Finally, the fiberoptic bronchoscopy confirmation as a reference standard was used to confirm the position of the tube. Under manual ventilation, by sequentially clamping the tracheal and bronchial limbs of the tube, clinical confirmation was made by auscultation, capnography, visualizing the chest wall expansion, and perceiving the lung compliance in the reservoir bag. Ultrasound confirmation was obtained by visualizing lung sliding, diaphragmatic movements, and the appearance of lung pulse sign. RESULTS: The sensitivity of the clinical method was 84.5%, with a specificity of 41.1%. The positive and negative likelihood ratio was 1.44 and 0.38, respectively. The sensitivity of the ultrasound method was 98.6%, specificity was 52.9%, with a positive likelihood ratio of 2.10 and a negative likelihood ratio of 0.03. Comparisons between the diagnostic performance of the 2 methods were calculated with McNemar's test. There was a significant difference in sensitivity between the ultrasound method and the clinical method (P=.002). Nevertheless, there was no statistically significant difference in specificity between both methods (P=.34). A p value<.01 was considered statistically significant. CONCLUSION: Lung ultrasound was superior to the clinical method in confirming the adequate position of the left double-lumen tube. On the other hand, in confirming the misplacement of the tube, differences between both methods could not be ensured.

Cultivo de cepas de levaduras de suelo trumao en ®vinaza¼ / Cultivation of yeast strains of the trumao soil in ®vinasse¼

30 cepas de levaduras aisladas desde un suelo trumao (Hapludans) usado como pradera en rotación, se cultivaron individualmente (100 µl = a 102 ufc delevaduras/mL) en matraces con 50 mL de ®vinaza¼, estos fueron incubados en un agitador orbital a 150 rpm, 23 °C por 5 días, luego de la incubación el contenido de cada matraz se centrifugo a 3.500 rpm por 20 min., a los pellet obtenidos se les determino: el peso seco (PS); fosforo total (FT) por digestión ácida y posterior lectura a 400 nm; proteínas totales (PT) por colorimetría Biuret a 595 nm y lípidos totales (LT) mediante el método colorimétrico de la sulfo-fosfo vainillina a 520 nm. Las 30 cepas de levaduras crecieron en la vinaza. El mayor PS lo registro la cepa 25 (331 g de levadura L-1 de ®vinaza¼). FT lo registro la cepa 28 (4,8 mg g-1 de levadura seca). PT lo registro la cepa 24 (25,90 mg g-1 de levadura seca) y LT lo registro la cepa 18 (287,4 mg g-1 de levadura seca).

Thirty strains of yeast isolated from a volcanic ash soil (Hapludans), used as pasture rotation, were individually cultured (100 µl = 102 cfu of yeast cells mL-1) in flasks with 50 mL of ®vinasse¼, these were incubated at 23 °C for 5 day, after incubation the contents of each flask was centrifuged at 3500 rpm for 20 min, the pellet obtained was determined: dry weight (DW); total phosphorus (FT) by acid digestion and later reading at 400 nm; total protein (TP) by Biuret at 595 nm and total lipid (TL) by the colorimetric method of the sulfo-phospho-vanillin at 520 nm. The Thirty strains of yeast grown on vinasse. The best DW, was determined for strain 25 (331 g yeast L-1 ®vinasse¼). FT was determined for strain 28 (4,8 mg g-1 dry yeast). TP was determined for strain 24 (25, 90 mg g-1 dry yeast) and TL was determined for strain18 (287, 4 mg g-1 dry yeast).

Caveolin-1 in cell migration and metastasis.

Caveolin-1 is a member of the caveolin family that has been ascribed a dual role in cancer. In early stages of disease the protein functions predominantly as a tumor suppressor, whereas at later stages, caveolin-1 expression is associated with tumor progression and metastasis. Here, some mechanisms associated with caveolin-1-dependent tumor suppression will be briefly discussed before focusing on the role of this protein and particularly phosphorylation of tyrosine-14 in promoting cell migration, invasion and metastasis. Models are provided summarizing possible explanations for these dramatic changes in function, as well as mechanisms by which this may be achieved.

Recovery from experimental parkinsonism by semaphorin-guided axonal growth of grafted dopamine neurons.

Cell therapy in animal models of Parkinson's disease (PD) is effective after intrastriatal grafting of dopamine (DA) neurons, whereas intranigral transplantation of dopaminergic cells does not cause consistent behavioral recovery. One strategy to promote axonal growth of dopaminergic neurons from the substantia nigra (SN) to the striatum is degradation of inhibitory components such as chondroitin sulphate proteoglycans (CSPG). An alternative is the guidance of DA axons by chemotropic agents. Semaphorins 3A and 3C enhance axonal growth of embryonic stem (ES) cell-derived dopaminergic neurons in vitro, while Semaphorin 3C also attracts them. We asked whether intranigral transplantation of DA neurons, combined with either degradation of CSPG or with grafts of Semaphorin 3-expressing cells, towards the striatum, is effective in establishing a new nigrostriatal dopaminergic pathway in rats with unilateral depletion of DA neurons. We found depolarization-induced DA release in dorsal striatum, DA axonal projections from SN to striatum, and concomitant behavioral improvement in Semaphorin 3-treated animals. These effects were absent in animals that received intranigral transplants combined with Chondroitinase ABC treatment, although partial degradation of CSPG was observed. These results are evidence that Semaphorin 3-directed long-distance axonal growth of dopaminergic neurons, resulting in behavioral improvement, is possible in adult diseased brains.

Behavioral characterization of non-copulating male mice.

Non-copulating (NC) males are those animals that do not mate in spite of repeated testing with sexually receptive females. They have been observed in several species including rats and mice. The present experiment was designed to perform a detailed behavioral characterization of NC male mice. Thus, we evaluated their sexual incentive motivation for a sexually receptive female or a sexually active male, olfactory preference for volatile and non-volatile odors from females or males, and olfactory discrimination between female and male volatile odors and food related odors (milk versus vinegar). We compared the activity of the accessory olfactory system (AOS) in copulating (C) and NC males in response to estrous bedding using the induction of Fos-immunoreactivity (Fos-IR) as a measure of neuronal activation. We also determined if estradiol or dopamine treatment could induce sexual behavior in NC males. Finally, we compared the testis weight and the number of penile spines in C, NC, and gonadectomized males. In the sexual incentive motivation test C males spend significantly more time in the female incentive zone than in the male incentive zone. On the other hand, NC males spend the same amount of time in both incentive zones. In tests of olfactory preference, NC males spent less time investigating estrous odors than C males. As well, NC males discriminate urine from conspecifics but they spend less time smelling these odors than C males. In addition, no increase in Fos expression is observed in NC males when they are exposed to odors from estrous females. Our data also suggest that the deficits observed in NC males are not due to lower circulating levels of gonadal hormones, because estradiol supplementation does not induce sexual behavior in these animals, and their testis weight and the number of penile spines are normal. The results suggest that NC males are not sexually motivated by the receptive females and their odors.