A case of prevailing deficit of nonliving categories or a case of prevailing sparing of living categories?

We describe a new case of semantic deficit in which nonliving categories are disproportionately impaired. PL, a woman affected by progressive degeneration of the left temporal lobe, was examined twice, at a distance of 1 year. The deficit was first apparent on naming and on a verbal semantic questionnaire, but a year later nonliving categories were disproportionately affected also on verbal comprehension (word/picture matching task). Body parts and musical instruments were also investigated: the former was the best preserved category, whereas the latter was the most severely affected. Considering all categories, functional and perceptual information was not differently affected, but there was a trend toward a worse score for nonliving category functional questions. Discussing the current hypotheses on the genesis of category dissociations, we conclude that nonliving categories might not be a true domain, and that their impairment could simply derive from the relative sparing of the domains of the living categories, for which separate cognitive and anatomical representations can be better postulated. Finally, we discuss the problems raised by published cases in an attempt to find a consistent anatomical substrate for category dissociations.     

Neural modeling of a visual perceptual task—a case study

A model connecting psychophysical findings with their putative neurobiological substrate is examined: the attempt to relate the perception of the orientation of a line in visual space to the excitation pattern of orientation-selective neurons in the mammalian visual cortex. The specific problem is whether it is possible to derive the phenomenon of ‘simultaneous orientation contrast’, also known as the tilt illusion, from neurophysiological data by comparing the responses to similar visual patterns obtained from human observers and from visual cortical neurons in anesthetized cats. It was hoped that straight-forward concepts such as lateral inhibition in the domain of line-orientation would lead to a satisfactory model. The neurophysiological findings, however, turn out to be much more complex, particularly as contextual stimulation (non-classical receptive fields) of cortical neurons produces some hitherto unsuspected effects. When constructing neural models of visual psychophysical responses, we clearly need to consider not only non-classical receptive fields but also the fact that neural ‘filtering’ is likely to be active rather than passive.     

A case of disproportionate macrodactyly or a mild form of Proteus syndrome? An interesting case

We present a 20-year-old Malay male whom we believe has Proteus syndrome, a rare congenital disorder of asymmetrical overgrowth of body tissues. There are fewer than 100 confirmed cases reported worldwide thus the clinical presentation and histopathological findings are of significance. Our patient presented with an overgrown right small finger and subcutaneous purplish pigmentation over his left upper arm and chest since birth. His small finger gradually increased in size. He had no abnormalities in sensation or power. Radiographs revealed a delta shaped middle phalanx of the small finger. His activities of daily living were uninterrupted but he requested debulking surgery for cosmetic reasons. Histopathological examination reported hypertrophic fatty tissue composed of well formed lobules of mature adipocytes interspersed with fibrous elements.     

Molecular cytogenetic characterization of a case of Müllerian adenosarcoma

Müllerian adenosarcoma is a distinctive type of mixed Müllerian tumor of the female genital tract. To our knowledge, no cytogenetic data have been documented on Müllerian adenosarcoma in the literature so far. We report here the chromosomal findings of a Müllerian adenosarcoma in a 15-year-old female. Cytogenetic and molecular cytogenetic analysis revealed a complex karyotype involving chromosomes 2, 8, 10, 13, 19, and 21. These numerical and structural abnormalities may be of etiologic significance. This report may highlight the potential value of molecular cytogenetic analysis in differential diagnosis of Müllerian tumors. More cases are warranted to further genetically characterize this type of neoplasm.     

Is manioc a diabetogenic factor? Apropos of a case of diabetes mellitus with a large consumption of crude manioc

The case of a 24 year-old Comorian male patient consuming large amounts of cooked and uncooked cassava and suffering of malnutrition since his boyhood is reported. The patient presented a diabetes mellitus by chronic calcific pancreatitis with retinopathy and neuropathy. The protein deficiency associated with eating uncooked cassava may be recognised as a factor of calcific pancreatitis diabetes. Other factors might be associated such as the environment as well as immunological and genetic characteristics.     

Large solitary fibrous tumor of the oral cavity—Report of a case

The solitary fibrous tumor (SFT) is a rare soft tissue tumor with a substantially benign clinical behavior. The SFT of the oral cavity is a very uncommon entity. It is also of complicated diagnosis because of its extensive morphologic diversity and because of its similarity to many mesenchymal tumors. A 44-year-old man was referred for management of an asymptomatic lesion in the left buccal mucosa, which had been identified 10 years earlier. Intra-oral examination revealed a well-demarcated, fibroelastic, rounded exophytic mass located in the left buccal mucosa. The mass was covered with a non-ulcerated mucosa of normal color and measured approximately 4.0 cm in diameter. Histopathological examination showed proliferation of spindle-shaped cells arranged in fascicles and in a patternless pattern, highly vascularized, with focal staghorn vessels. Immunohistochemical analysis revealed diffuse positivity for CD34 and focal positivity for Bcl-2. Awareness of the morphological diversity of SFT coupled to a judicious use of appropriate immunohistochemical probes should prove valuable to accurately segregate SFT from other spindle cell neoplasms.     

Biodiversity and leptospirosis risk: a case of pathogen regulation?

Well balanced ecosystems have an essential role in disease regulation, and consequently their correct functioning is increasingly recognised as imperative for maintaining human health. Disruptions to ecosystems have been found to increase the risk of several diseases, including Hantavirus, Lyme disease, Ross River virus, malaria and Ciguatera fish poisoning. Leptospirosis is a globally important emerging zoonosis, caused by spirochaete bacteria, borne by many mammalian hosts, and also transmitted environmentally. We propose that leptospirosis incidence in humans is also linked to ecosystem disruption, and that reduced biodiversity (the diversity of species within an ecological community) may be associated with increased leptospirosis incidence. To investigate this hypothesis, the relationship between biodiversity levels of island nations and their annual leptospirosis incidence rates (adjusted for GDP per capita) was examined by linear correlation and regression. Supportive, statistically significant negative associations were obtained between leptospirosis incidence and (a) total number of species (r² = 0.69, p < 0.001) and (b) number of mammal species (r² = 0.80, p < 0.001) in univariate analysis. In multivariable analysis only the number of mammal species remained significantly associated (r² = 0.81, p = 0.007). An association between biodiversity and reduced leptospirosis risk, if supported by further research, would emphasise the importance of managing the emergence of leptospirosis (and other infectious diseases) at a broader, ecosystem level.     

Malignant clear-cell myomelanocytic tumor of broad ligament—a case report

Clear-cell myomelanocytic tumors (CCMT) of the perivascular epithelioid cell tumor (PEComa) family have been recently reported. We report a case involving a 12-year-old girl. The tumor (9 × 7.5 × 7 cm) was a firm, tan–gray mass with heavily dark pigmentation, massive hemorrhage, and necrosis, and was located in the right broad ligament attached to the right ovary. Histologically, the tumor was composed of polygonal cells exhibiting diffuse hemorrhage, multifocal necroses, and vascular invasion. Most of the tumor cells contained melanin pigments with Fontana–Masson positivity and ultrastructurally suspicious, membrane-bound premelanosomes. Immunohistochemical staining was positive against HMB-45 and focally positive for smooth muscle actin. The tumor recurred in the form of multiple conglomerated masses of the right iliac fossa, with the greatest measuring up to 3.8 cm in dimension, within 1 year. Most CCMT are believed to originate from falciform ligament/ligamentum teres. To the best of our knowledge, this is the second report of a CCMT arising in the broad ligament with typical morphology and contributory ancillary results. Further study for proper subclassification of the PEComa family should be validated, not by anatomic site but by clinical behavior.     

Antibody humanization: a case of the 'Emperor's new clothes'?

The antiglobulin response is perceived as a major problem in the clinical development of therapeutic antibodies. Successive technical developments such as chimeric, humanized and, now, fully human antibodies claim to offer improved solutions to this problem. Although there is clear evidence that chimeric antibodies are less immunogenic than murine monoclonal antibodies, little evidence exists to support claims for further improvements as a result of more elaborate humanization protocols.     

Long-term survivorship of a unicondylar knee replacement — A case report

Unicondylar knee arthroplasty (UKA) was introduced in the 1970s as a treatment option for isolated knee compartment gonarthrosis. Early results were discouraging secondary to poor patient selection, suboptimal surgical technique, and inferior prosthetic design. In recent years, there has been resurgence in the use of the UKA. Improvements in implant design, surgical technique, and patient selection have led to multiple studies demonstrating 94–98% survivorship of the implants at a 10 year follow-up. However, there still remains a paucity of evidence with regard to this treatment option for young, active patients. This case report presents the longest recorded follow-up (31 years) of a UKA in a young, active patient and it highlights that with appropriate patient selection and meticulous surgical technique, UKA may have a role as a long term treatment option in patients with isolated unicompartmental disease.     

The Guillain-Barré syndrome: a true case of molecular mimicry

Molecular mimicry between microbial antigens and host tissue forms an attractive hypothetical mechanism for the triggering of autoimmune disease by preceding infections. Recent crucial reviews state that molecular mimicry, as the causative mechanism, remains unproven for any human autoimmune disease. However, the peripheral neuropathy Guillain-Barré syndrome (GBS) is largely overseen in this debate. Based on recent evidence, we argue that GBS should be considered as an excellent paradigm and an attractive model for elucidation of both host and microbial aspects of molecular mimicry.     

A case of a femoral neck tumor: painless osteroid osteoma?

We report herein a unique, previously unreported, successful outcome for a patient untreated for a tumor affecting a femoral neck considered as painless osteoid osteoma. The lesion was detected by chance at examination for groin injury. Diagnosis was based on the plain radiography, bone scan, and computed tomography. The results of the full blood examination were normal. Neither pharmacomedical nor surgical treatments were given. Two years later, radiological resolution of the lesion was revealed. The patient was observed between 1995 and 2002. We conclude that painless osteoid osteoma should be included in the differential diagnosis of asymptomatic femoral neck lesions. Our case suggests that osteoid osteoma has a tendency to regress over time and that conservative management appears to be a reliable option.     

Abnormal granulation of blood granulocytes in mucopolysaccharidosis VI—a case report

Mucopolysaccharidosis (MPS) is a group of lysosomal storage disorders in which there is deficiency of specific enzymes. Depending upon the enzyme which is deficient and the nature of the material that accumulates at various tissues, the MPS is divided into 8 types (MPS I to MPS VIII). In MPS VI, deficiency of aryl B sulfatase leads to the accumulation of dermatan sulfate. Mucopolysaccharidosis VI, also called as Maroteaux-Lamy syndrome, in its severe form presents with bony lesions, corneal clouding, hepatosplenomegaly, cardiovascular abnormalities, and central nervous system deterioration. This form of MPS features the most striking abnormal granulation in the circulating white blood cells. Mucopolysaccharidosis VI has an estimated global incidence of 1 in 340 000. The number of cases showing abnormal granules in the cytoplasm of leucocytes is still rarer. We report a case of MPS VI with abnormal granules in the circulating blood leukocytes.     

Dopamine in disturbances of food and drug motivated behavior: a case of homology?

Highly palatable food and drugs of abuse share the ability to stimulate dopamine transmission in the shell of the nucleus accumbens. However, while in the case of food this property is adaptively regulated in a negative fashion upon repeated exposure to the reward, no such regulation is operative towards drugs of abuse. Dysadaptive stimulation of dopamine transmission in the accumbens shell is assigned an important role in the compulsive motivation for drugs typical of drug addiction. It is speculated that disturbances of feeding behavior are related to loss of adaptive regulation of food-stimulated release of dopamine in the shell of the accumbens.     

An impressive case of chromoblastomycosis due to Fonsecaea pedrosoi in a patient with a long history of fungal infection

Chromoblastomycosis is defined as a chronic cutaneous and subcutaneous fungal infection caused by melanized or brown-pigmented fungi. A 63-year-old man farmer showed on external and internal part of the right arm, a well-delimited verrucous and hyperkeratotic plaque, with atrophic and cicatricial areas. Direct examination of skin scrapings samples showed the presence of muriform cells, a classic feature of chromoblastomycosis. Fungal isolation was performed in Sabouraud dextrose agar, and dark olivaceous colonies were isolated. Skin biopsy samples were obtained for histopathological and molecular diagnosis. DNA extracted from both, paraffin-embedded skin biopsy samples and fungal colonies, was used for molecular identification by 18S-ITS1-5.8S-ITS2-28S rRNA amplification and sequencing. Fonsecaea pedrosoi was identified from paraffin-embedded skin samples and fungal colonies. A combined therapy with terbinafine and itraconazole, plus cryotherapy was applied with an important improvement. Herein, we report an impressive case of chromoblastomycosis due to Fonsecaea pedrosoi with a successful outcome.