Ultrastructural description of an unidentified apicomplexan oocyst containing bacteria-like hyperparasites in the gill of Crassostrea rizophorae.

Oocysts of an unidentified coccidian are reported in this study to parasitize the gills of the oyster Crassostrea rizophorae (Mollusca, Bivalvia) collected near the city of Recife (Itamaracá Island, 07 degrees 38' 00" S, 34 degrees 48' 06" W), Brazil. Oocysts appeared as light and dense forms, both containing rod-shaped, bacteria-like hyperparasites (BL). Both light and dense oocysts were spherical, 4.3 to 4.7 pm in diameter, but denser oocysts had irregular contours. Both forms consisted of a thick dense wall (approximately 165 nm thick) consisting of 3 layers. The outermost, a dense and irregular layer about 25 nm thick, possessed numerous bead-like structures and some slender conical projections (up to 1.5 microm long). The inner layer of the wall was formed by a dense and homogenous layer about 125 nm thick. Between these 2 layers, a thin light layer about 12 nm thick was present. Uninucleated sporocysts occupied the internal space of the oocyst and contained some rod-shaped BL and mitochondria surrounded by numerous ribosome-like particles. The dense forms of the oocysts showed the same structures described in the lighter forms and appeared to be the final maturation form of the oocysts. Free sporozoites were occasionally observed among oocysts.

Ultrastructural studies of spermiogenesis of the clamLucina pectinata (Bivalvia, Lucinidae) from Northern Brazil

Spermatogenesis and sperm ultrastructure of the clam Lucina pectinata (Lucinidae) from northern Brazil were studied using light and transmission electron microscopy. The uniflagellate spermatozoa are grouped into characteristic rings within somatic cells (Sertoli-like cells), with the acrosome oriented toward the peripheryof these cells. The spermatozoa are long cells of the primitive type (ect-aquasperm) with a total length of 50.2 ± 2.5 mm, consisting of head (acrosome + nucleus), midpiece and tail. Acrosome is formed by an, acrosomal vesicle with a conical cylinder-like shaped (0.9 ± 0.1 mm length and 0.4 ± 0.1 mm in basal diameter) having a deeply infolded basis occupied by the subacrosomal space, containing flocculent material without axial rod. The acrosomal vesicle is formed by a membrane-bounded containing a broad basal ring of electron-dense material. The nucleus (7.5 ± 0.8 mm long) is an elongated, subcylindrical rod-shaped, slightly and gently curved, with a basal invagination (0.2-0.4 mm). It contains dense chromatin without any electron-lucent lacunae.The midpiece (1.0 ± 0.3 mm long; 1.1 ± 0.2 mm width) consist of four equal mitochondria located at the same level, surrounding two centrioles arranged at right angles. The proximal centriole lies at 90° relative the distal centriole and sperm longitudinal axis. The tail (40.5 ± 2.1 mm long) contains the common 9 + 2 pattern which in tapering end piece is successively reduced and sheated by the plasmalemma.

Development of the cribriform plate and of the lamina mediana.

The development of the cribriform plate and lamina mediana was studied in macerated isolated ethmoid bones in specimens from late fetal life to the stage of its final shape (60 specimens). From fetal life to the first year of age, the ethmoid bone consisted of two separate symmetrical halves which had joined together by the end of the first year. Each half of the future ethmoid bone incorporated the superior, middle and occasionally also the supreme nasal concha. The ossification of the cribriform plate started in the new-born where it initially displayed a vertical position but became horizontal in the course of the first year. At the end of the first year both halves of the ethmoid bone had been united by the formation of the crista galli, lamina mediana and complete ossification of the cribriform plate. The lamina mediana reached its final shape by ten years of age. Each half of the ethmoid bone displayed furrows for the fila olfactoria in the region of the superior and occasionally also of the anterior part of the middle nasal concha. The furrows run in a postero-anterior direction. In the course of our investigations we found three cases where all three nasal conchae formed a unique block thus proving the common origin of these structures from the cartilaginous nasal capsule.

Acanthocollaritrema umbilicatum Travassos, Freitas & Bührnheim, 1965 (Digenea: Acanthocollaritrematidae) from the common snook, Centropomus undecimalis, from Itamaracá, state of Pernambuco, Brazil.

Acanthocollaritrema umbilicatum Travassos, Freitas and Bührnheim, 1965, is the only species of Acanthocollaritrematidae described up to the moment. The systematic position of this species and the validity of the family has been questioned by the possible presence of a gonotyl and a genital atrium associated to the acetabulum. In this paper, specimens of this trematode, collected from Centropomus undecimalis cultivated at Itamaracá, State of Pernambuco, northeast Brazil, were studied under optical and scanning electron microscopy, and compared with available sintypes. Gonotyl and genital atrium were not observed and both family and species are considered valid taxonomic entities. A. umbilicatum is redescribed with the addition of new morphological information.

Local interferon therapy for melanoma patients.

BACKGROUND: Melanoma, once considered a rare form of cancer, is increasing in incidence throughout the world. The prognosis of malignant melanoma is inversely related to the depth of tumor invasion. METHODS: Twenty-seven patients were treated with r.IFN alpha 2c. Four patients were treated with human natural leukocyte interferon (HNLI). Interferon was applied locally. Historical control groups were used for comparison in the statistical analysis. The data were evaluated taking into account the single risk factor Clark levels III and IV. In the control group there were 10 patients with Clark levels III and IV; in the group of r.IFN apha 2c-treated patients there were 20 patients. The data were analyzed by using the Kaplan-Meier and Cox methods. RESULTS: The percentage of survivals was higher in the interferon-treated groups with Clark levels III and IV, than in the control group, that is 60% compared to 25%, and 40% compared to 33%, respectively. The results of the statistical analysis after 60 months of follow-up are significantly better in the interferon group (P = 0.0175). CONCLUSIONS: The control group was not selected at random. Therefore, on the basis of our results, one can say that the treatment of the melanoma patients, Clark levels III and IV, with the r.IFN alpha 2c is promising and that further investigation is justified.

Interferon reduces recurrences of basal cell and squamous cell cancers.

BACKGROUND: Interferon is considered to be an important curative agent for dermatologic diseases. We report the follow-up experience of patients with basal cell or squamous cell carcinomas treated with human natural leukocyte interferon (HNLI). RESULTS: Among 52 patients with basal cell carcinoma (BCC) treated with HNLI more than 10 years ago, and among 58 treated more than 5 years ago, only 2 recurrences were observed. There were no recurrences in 75 patients who had a complete response to HNLI treatment, nor were there any in 20 patients with either a partial or complete response to r.IFM alpha 2c treatment. Of 52 patients with squamous cell carcinoma (SCC), 31 had been treated more than 10 years earlier, two recurrences of the disease at the site of the original lesion were observed. CONCLUSION: Interferon treatment makes it possible to achieve a persistent cure in patients with BCC and SCC in a high proportion of cases. The potential advantage of nonsurgical treatment are an enhancement of cosmetic results through the prevention of destruction of important anatomic structures.

Local interferon therapy for lip carcinoma.

In a prospective non-randomized study 21 patients with lower lip squamous cell carcinoma were treated with human natural leukocyte interferon (HNLI). The response rate was measured by a size reduction of more than 25% and was 81%. A complete response rate was considered to be a cure according to histopathological and clinical findings and was 48%. The response rate of six lower lip squamous cell carcinoma cases treated with recombinant interferon alpha 2c was 67% and the complete response rate was 17%. Three patients with basal cell carcinoma of the upper lip were also treated with HNLI. All three patients were cured, as determined by histopathological and clinical findings. These findings indicate that interferon can be a useful alternative therapy for lip carcinoma either with or without surgery.

Basal cell carcinoma treated with interferon.

Human natural leukocytic interferon (HNLI) and recombinant interferon (rIFN) alpha 2c can be used in the therapy of basal cell carcinoma. Seventy-two patients were treated for 3 to 6 weeks with a single dose of 400,000 to 1,200,000 units (HNLI) and 2,000,000 to 5,000,000 units (rIFN alpha 2c). According to histopathologic and clinical findings, 52 patients were cured, and cancer cells were not found in the biopsy material taken after HNLI treatment for the second biopsy. In nine of 72 patients the cancer lesion was reduced 25% to 90%. In 11 patients it was not reduced or was reduced less than 25%. With rIFN alpha 2c therapy given five times per week for 4 weeks, histopathologic and clinical findings showed that five patients out of 12 were cured, and cancer cells were not found in the biopsy material taken after treatment. In seven patients out of 12 the cancer lesion was reduced 25% to 90%. Both types of interferons are effective in the treatment of basal cell carcinoma. Side effects were mild.

Interferon therapy for basal cell carcinoma and squamous cell carcinoma.

Totally 161 basal cell and squamous cell carcinoma (BCC, SCC) patients were treated with human natural leucocytic interferon (HNLI) and recombinant IFN alpha 2c. After HNLI treatment, 61 out of 86 BCC patients and 29 out of 45 SCC patients were cured according to histopathologic and clinical findings. In 13 BCC and 13 SCC patients, the cancer lesion was reduced 25%-90%. After recombinant IFN alpha 2c treatment, 14 of 20 BCC patients and 4 of 10 SCC patients were cured according to histopathologic and clinical findings. In 6 BCC patients and 5 SCC patients the cancer lesion was reduced 25% to 90%. Both types of interferons are effective in the treatment of BCC and SCC patients. Local application of interferon stimulates immune reaction at the site of the tumor. There is a marked difference between the spontaneous macrophage activity and that induced by interferon. The interferon activated macrophages are significantly larger, the number of lysosomes and the density of macrophages is increased. In difficult locations intralesional therapy can be considered to avoid disfigurement of the patients with or without surgery.

The complications of external rhinoplasty.

An analysis of complications of 867 consecutive external rhinoplasties over a 14-year period is presented. The most common intraoperative complication was excessive bleeding. Transient epiphora, bleeding, excessive and/or prolonged edema, septal dematoma, transient anosmia and various problems with packing were observed in the early postoperative period. Late complications included hypertrophic scar, localized periostitis, skin telangiectasia, etc. The complications of external rhinoplasty are comparable in incidence and severity of standard endonasal rhinoplasty.

Treatment of squamous cell carcinoma with interferon.

Human natural leukocytic interferon and recombinant HulFN alpha 2c can be used in the therapy of squamous cell carcinoma. The duration of treatment was 3-6 weeks. A single dose was 400,000-5,000,000 units given weekly for 3-6 weeks. Clinically and histologically 19 of 32 patients were cured and tumor cells were not found in the material taken after interferon treatment for the second biopsy. In ten patients tumor size was reduced 25-90%, and in three patients tumor size was not reduced according to clinical findings. With recombinant HulFN alpha 2c therapy given 5 times per week for 4 weeks. Four of ten patients with similar tumors were cured clinically and histologically clinical findings. In five patients tumor size was reduced 25-90%, while in one patient there was no reduction in tumor size. Both types of interferons are effective in the treatment of squamous cell carcinoma. Side reactions were mild.

The effect of short-wavelength ultraviolet light on antigens, lectin receptors and the ultrastructure of Crithidia fasciculata.

Crithidia fasciculata is an important trypanosomatid parasite commonly affecting insects and is used extensively as a model for the study of the biochemistry, ultrastructure and organization of the kDNA network of trypanosomatids. The present study describes the evolution of UV-induced morphological changes detectable by transmission electron microscopy in Crithidia fasciculata. Although only rare and minor changes in kinetoplast DNA were demonstrable 7 h after UV irradiation, alterations of this organelle were present in almost all flagellates observed 24 h and 48 h after irradiation. Other cell structures were apparently undamaged. Ultrastructural changes in kDNA did not correspond to changes in antigenicity of protein bands in western blotting against serum from Chagas' disease patients or in the presence of 3 different lectin receptors on the surface of the parasite.

The effect of short-wavelength ultraviolet light on antigens, lection receptors and the ultraestructure of Crithidia fasciculata

Crithidia fasciculata is an important trypanosomatid parasite commonly affecting insects and is used extensively as a model for the study of the biochemistry, ultrastructure and organization of the kDNA network of trypanosomatids. The present study describes the evolution of UV-induced morphological changes detectable by transmission electron microscopy in Crithidia fasciculata. Although only rare and minor changes in Kinetoplast DNA were demonstrable 7 h after UV irradiation, alterations of this orgtanelle were present in almost al flagellates observed 24 h and 48 h after irradiation. Other cell structures were apparently undamaged. Ultrastructural changes in kDNA did not correspond to changes in antigenicity of protein bands in western blotting against serum from Chagas' disease patients or in the presence of 3 different lectin receptors on the surface of the parasite

[Occurrence of Campylobacter pylori in patients with gastritis and peptic ulcer]. / Ocorrência do Campylobacter pylori em pacientes com gastrite e úlcera péptica.

Endoscopic biopsies from the gastric antrum and margin of peptic ulcers (gastric and duodenal) were obtained from 56 patients for histologic and microbiologic studies in order to establish the occurrence of Campylobacter pylori. Thirty nine of them had antral gastritis and in 37 (94.8%) the bacteria was detected. In 17 cases with normal mucosa the culture was positive in only 2 of them (p less than 0.01). Patients with duodenal and gastric ulcer had a 100% and 88.8%, respectively, of positivity to C. pylori at samples from the margin of the lesions. Bacteriologic findings were similar to those described in the literature. At the electronic microscopy bacilli were found near or adhering to the cellular surface without signs of intraepithelial penetration. This study confirms the association between C. pylori and gastritis and peptic gastroduodenal ulcer.

The true threshold of the slow nystagmic component-L.

The fast component of nystagmus begins where the slow component stops, at the point called the threshold of the fast component R. The fast component should last until the eye is brought back into the position of azimuth zero, where the slow component begins anew. This point can be called the threshold of the slow component L. So the fast component has a span from R to L and is presented as a side of a triangle r. An additional corrective procedure in electronystagmography is suggested to avoid failures and to define the true position of L. This is the way to correct the false information on nystagmic elements and to learn the unknown features of the fast component.

Morphometric study of the plasmalemmal vesicles of the capillaries of the rat cerebellum, heart, diaphragm and lung during perinatal growth.

1. Morphometric techniques were used to determine the variation in number of plasmalemmal vesicles, their area and the area of the endothelium in capillaries of the cerebellum, heart, diaphragm and lung of rat fetuses aged 17, 19, 20 and 21 days and of newborn rats. 2. A curve fitting procedure showed that the evolution of vesicle number could be properly expressed by equations of the type y = aoekx, where y = number of vesicle images per capillary section or number of vesicles per micron3 of capillary wall, and x = age in days. The time necessary for the numerical density of the vesicles to duplicate in the capillary wall is on average 1.1-1.3 days in the lung, 1.4-1.9 days in the muscular organs and 2.3 days in the cerebellum. 3. Capillary maturation was characterized by thinning of the endothelium, especially for those at the base of the lung, and by increased numbers of vesicles. 4. The ratios: number of plasmalemmal vesicle images/endothelial area, plasmalemmal vesicle image area/endothelial area, and number of plasmalemmal vesicle images/plasmalemmal image area increased with age. The third parameter tended to reach 1 due to the increased area of the vesicles as a function of their numbers, even though there was a decrease in individual vesicle size.

Schistosoma mansoni: structural damage after treatment with oxamniquine.

The effects of a single dose (100 mg/kg-body weight of mouse) of oxamniquine on the worm's tegument and paranchyma in relation to the process of immunological granulomatous reaction of the host's liver are described under light and electron microscopy (EM). The lesions caused by the drug are sequentially and simultaneously described in form of swelling, surface bulble and disruption with erosions. Ulceration in the tubercules with loss of spines is often more extensive and severe in male worms and concentration of host's mononuclear cells is observed. The possible role of host's immune response is discussed.