Assessment of the diet of patients with rheumatoid arthritis and osteoarthritis

There have been many and divergent thoughts expressed both in the scientific and in the lay literature regarding diets for patients with arthritis (1-8). However, few experimental observations pertain to either the nutritional status of arthritis patients or the clinical value of putative nutritional therapies (1-8). Until such time as the notion that dietary manipulation can alleviate particular symptoms for selected patients is proved, it is prudent to advise patients to maintain sound nutritional practices in accordance with contemporary standards (4-8, 13-16). Our data indicate that many arthritis patients are at least marginally inadequate in selected nutrients, some of which (vitamin E and zinc) might relate to immunologic events important in perpetuating the disease. These observations provide a basis for nutritional counseling of arthritis patients.

Epithelial markers in the diagnosis of nasopharyngeal carcinoma: an immunocytochemical study

Immunocytochemical stains for three epithelial cell markers--keratin, epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA)--have been examined on paraffin-embedded material from 14 patients with nasopharyngeal carcinoma (NPC). Tumour cells staining positively for keratin were found in all cases and for EMA in eight; two tumours contained CEA-positive cells. Seven cases of Hodgkin's disease and 24 non-Hodgkin's lymphomas were uniformly negative. Keratin is the most reliable epithelial marker for identifying NPC and excluding lymphoma. The regular finding of stainable keratin in non-keratinising and anaplastic NPC supports the view that NPC is a homogeneous group exhibiting variable degrees of squamous differentiation.

Diet therapy for rheumatoid arthritis

Although diet therapy for arthritis has received considerable publicity, there is little objective information about its efficacy. We undertook a 10-week, controlled, double-blind, randomized trial of patients with active rheumatoid arthritis (RA). Twenty-six patients completed the study; 11 were on an experimental diet (a specific popular diet free of additives, preservatives, fruit, red meat, herbs, and dairy products) and 15 were on a "placebo" diet. Of 183 variables analyzed, there were no clinically important differences among rheumatologic, laboratory, immunologic, radiologic, or nutritional findings between patients on experimental and placebo diets. Six RA patients on the placebo and 5 on the experimental diet improved by objective criteria. Improvement averaged 29% for patients on placebo and 32% for patients on experimental diets. Two patients on the experimental diet improved notably, elected to remain on the experimental diet following the study period, have continued to improve, and noted exacerbations of disease upon consuming nonexperimental diet foods. Our study failed to provide evidence of objective overall clinical benefit of this diet as followed by a group of patients with longstanding, progressive, active RA. However, our data are not inconsistent with the possibility that individualized dietary manipulations might be beneficial for selected patients with rheumatic disease.

Perineural spread by squamous carcinomas of the head and neck: a morphological study using antiaxonal and antimyelin monoclonal antibodies

Perineural spread has been demonstrated histologically in 65/180 (36%) major surgical resections for squamous carcinomas of the head and neck; the incidence in a smaller necropsy series was 18/20 (90%). Perineural infiltration was observed most commonly in the vicinity of carcinomas arising in the buccal cavity (31/63, 50%) and, at all sites, it was most commonly encountered near tumours less than or equal to 2.5 cm in diameter. Perineural spread near cervical node metastases was, by contrast, uncommon in the surgical series. Tumour within perineural spaces tends to be concentrated at the margin of the nerve and shows only limited extension inwards, but cells may track upwards and downwards within the spaces. Distant spread for greater than 2 cm is unusual, and interval sampling of involved nerves in necropsy material indicates that most perineural tumour cells are confined to the distal 1 cm of the affected nerve. Infiltrated nerves regularly show varying degrees of myelin and axonal degeneration, probably anoxic in origin, and segmental infarction of nerve trunks was observed in three patients. Fine changes in axons and myelin have been regularly demonstrated with two monoclonal antibodies, and the use of these new reagents is described.

Aphasia and speech organization in children

A long-standing controversy concerns whether lateralized cerebral specialization for speech and language is present at the time of language origins (developmental invariance) or whether it gradually develops from initial bilaterality (developmental progression). Thus controversy is complicated by conflicting reports of the incidence of childhood aphasia. The discrepancies are largely due to one early study. When methods for estimating speech organization distributions are applied to later studies, the developmental invariance position is supported.

Calcium phosphate deposition disease in great danes

A new clinicopathologic syndrome, possibly familial, in Great Dane dogs, resembles the familial childhood variant of calcium pyrophosphate dihydrate deposit disease in man, except that the mineral deposits were composed of amorphous calcium phosphate or hydroxyapatite rather than pyrophosphate. The syndrome was characterized clinically by paraplegia and incoordination in very young puppies which was caused by concentric constriction of the posterior cervical spinal cord. Canal stenosis resulted from dorsal displacement of the seventh cervical vertebra and deformation of the vertebral articular processes. Mineral deposition in the diarthrodial joints of the axial skeleton could be seen on radiographs of weanling puppies, and the appendicular skeleton became involved as the dogs matured. Periarticular mineralization of the limbs was associated with shorter bones, a thin cortex, abnormal bone curvature, and increased medullary trabeculae. Bone alterations were associated with abnormalities of the growth plate, which had focal areas of cartilage calcification. Soft tissue mineralization, seen in all dogs, was a primary feature of the disease process. Serum calcium concentrations were within the normal range, but serum phosphorus concentrations were decreased.

Pain and Dysphagia in Patients with Squamous Carcinomas of the Head and Neck: The Role of Perineural Spread

Clinical and pathological features of perineural spread have been investigated in patients with squamous carcinomas at several sites in the head and neck. In 100 surgical cases, the clinical and pathological findings were congruent in 76%. Combined clinical and histological evidence of perineural invasion was recorded in 33% and the overall incidence of nerve involvement detected morphologically was 44%. Perineural infiltration was demonstrated histologically in 51% of major excisions from the buccal cavity and in 34% of resections from the oropharynx, hypopharynx and cervical oesophagus. The neurological findings were dominated by hypoaesthesia, dysaesthesia and referred pain — Mainly in the territories of cranial nerves V and IX. Multiple and/or sequential nerve involvement was occasionally seen. No correlation was established between nerve invasion and metastasis to regional lymph nodes. Long-distance infiltration of nerve trunks, and multiple involvement, are grave prognostic features.

In 17 terminal patients submitted to autopsy, 65% had combined clinical and pathological evidence of perineural spread and the overall incidence of nerve involvement detected morphologically was 88%. Sensory changes again predominated. Multiple nerve involvement was observed in 35%. An apparently new ‘dysphagia syndrome’ is described in 4 patients with oropharyngeal carcinomas in whom gross mechanical obstruction was simulated by a combination of perineural spread of tumour into the ipsilateral vagal trunk, sometimes accompanied by segmental infarction, variable invasion of the sympathetic chain, and ‘splinting’ of the pharynx by local fibrosis and tumour in the soft tissues of the neck. Short-term palliation was achieved in these patients with high-dose steroids.

Decay of colostral antibodies to bovine leukemia virus with application to detection of calfhood infection

An estimated weighted-regression method was used to describe the decay of colostral bovine leukemia virus (BLV) antibodies in the calf, as measured by agar-gel immunodiffusion with glycoprotein antigen. The prediction equation, based on 473 observations from 130 animals, was log10 inverse titer = 1.29 -0.012 age (days). The half-life of BLV antibodies was estimated to be 25.8 days. Ages at which colostral antibodies were last detected were between 51 and 187 days. Normal limits of antibody decay were estimated and used to identify virus-induced active antibodies in calves during the colostral antibody period. Calves known to be infected were identified between 2 and 180 days of age, using 95% limits. Application of this procedure for the early serologic detection of BLV-infected calves in eradication or control programs is discussed.

Framework invasion by laryngeal carcinomas

The accuracy of standard clinical and radiologic methods in detecting invasion of the laryngeal framework or the presence of a transglottic tumor was examined by comparing clinical and pathologic findings in a series of 50 randomly selected laryngectomies for squamous carcinoma. Forty-two of the patients had received radiation therapy as primary treatment. The presence of pain referred to the ear immediately before laryngectomy indicated invasion of the laryngeal framework or spread into the extralaryngeal soft tissues in 11 of 12 patients. Transglottic tumors were correctly identified in 10 of 14 patients from laryngeal tomograms, but seven additional tumors were incorrectly designated as transglottic. Both transglottic tumors and infraglottic extension were seriously underdiagnosed by direct laryngoscopy. Framework invasion was seen to be a feature of transglottic tumors 2 cm or more in diameter. The morphology of this process is described. Limited follow-up has already shown a pattern of early recurrence, frequently as cervical node metastases, that is significantly more common in patients with framework invasion.

An immunocytochemical study of the distribution of epithelial membrane antigen in normal and disordered squamous epithelium

Using immunocytochemical techniques, we have investigated the distribution of epithelial membrane antigen (EMA) in human squamous epithelium. The antigen is not demonstrable in normal adult tissues although it is present on the surface membrane of normal foetal epidermis before keratinization takes place. It may be expressed strongly in the adult, however, in in situ and infiltrative squamous carcinomas as well as in a variety of non-neoplastic states. Present evidence suggests that EMA may protect exposed surfaces. The lack of demonstrable antigen on malignant melanomas and basal cell carcinomas highlights the histogenetic differences between these tumours and squamous carcinomas, and suggests a possible role for EMA in the differential diagnosis of malignant skin tumours.

A statistical approach to the determination of the fertile period

17 beta-Estradiol (E2), basal body temperature (BBT) and luteinizing hormone (LH), were measured in normally menstruating women. The preovulatory E2 observations were characterized by variations about a constant level during the preovula-peak. The BBT observations typically varied about a constant level during the preovulatory phase then about a higher constant level during the postovulatory phase. The change points in E2 and BBT were detected using a Bayesian detection rule and a midcycle 'fertile period' was marked off. The midcycle 'fertile periods' appear to bracket the ovulation event and the method shows promise as a natural family planning method. Several practical limitations of the method are discussed.

Fetal death in utero: effect on estrone, estradiol-17 beta and progesterone levels in the ewe

Polyvinyl catheters were placed in the maternal femoral artery (MA) and maternal uterine vein (UV) of 11 near-term ewes and in the umbilical vein of their fetuses. 1-5 days postoperatively 100 ml of air were injected into the umbilical vein of 7 fetuses. 4 fetuses served as controls. Samples of blood from MA were taken 15 min prior to air embolism and every 15 min for 3 h, then at +4, +5 and +6 h after air injection. Plasma levels of estrone (E1) estradiol (E2) and progesterone (P) were determined by radioimmunoassay. In MA and UV of treated ewes there was a significant decrease in P, but not in E1 or E2 after fetal death compared to control ewes. Control levels of P in MA were 9.6 ng/ml; values at 1, +2, +4 and +6 h were 8.8, 3.3, 2.3 and 1.2 ng/ml, respectively.

A Bayesian change-point problem with an application to the prediction and detection of ovulation in women

Under the assumptions of independent normally distributed and sequentially observed responses, a Bayesian rule for detecting a change from a constant mean response is derived. It is known that both basal body temperature (BBT) and preovulatory estrogen values undergo such a change in mean value at some random time during the menstrual cycle. The Bayesian rule is applied to estrogen to predict ovulation and to BBT to detect ovulation. Data from an aggregate of women are used to obtain prior information about the change-points and the parameters that define the changes in estrogen and BBT. A method is proposed by which the accumulation of information for a specific women can be incorporated into the aggregate prior information.

Reliability and validity of the 24-hour recall

The reliability and validity of the 24-hour dietary recall method was tested statistically by comparing observed with recalled intakes of kilocalories and protein. Data on observed intake of 28 children, aged 10 through 12, with asthma, cystic fibrosis, or diabetes, participating in a summer camp program, were obtained by unobtrusive observation. The same subjects were interviewed within 24 hours after the observation. Intakes of kilocalories and of protein were computed for both observed and recalled data. The two sets of data were compared by paired t-test and regression analysis. A large and significant difference was found between mean recalled and mean observed intakes for both kilocalories and protein. This coupled with a low but significant coefficient for reliability limits the usefulness of this dietary assessment tool in the age group studied.

Five human tumour cell lines derived from a primary squamous carcinoma of the tongue, two subsequent local recurrences and two nodal metastases

Five tumour cell lines have been derived from a primary squamous carcinoma of the tongue, from 2 subsequent local recurrences, and from 2 lymph-node metastases--all from the same patient. While the cell lines shared many morphological and biochemical characteristics, those derived from recurrences and metastases appeared to be less differentiated, were less well organized in culture, and displayed fewer desmosomes and tonofilaments than cells in the primary tumour line. A recurrent line showing greatest morphological divergence from the primary tumour line also demonstrated the greatest differences at the ultrastructural level, in increased production of plasminogen activator and in the composition of cell-surface glycoproteins.

The diagnosis and surgical management of olfactory neuroblastoma: the role of craniofacial resection

The diagnosis and clinical management of olfactory neuroblastoma are discussed. Computerized tomography is a valuable means of assessing the pre-operative extent of disease and the efficacy of subsequent major surgery. The tissue diagnosis is facilitated by electron microscopy, demonstrating the presence of dense core vesicles and cytoplasmic filaments. Radiotherapy followed by craniofacial resection is the treatment of choice for olfactory neuroblastomas that are locally extensive at presentation.

Ten human carcinoma cell lines derived from squamous carcinomas of the head and neck

Ten cell lines of human squamous carcinomas of the tongue and larynx have been established from surgical specimens removed from 36 unselected patients, in order to provide systems for investigating the invasive and tissue-destructive capacity of squamous carcinomas of the head and neck. The morphology, ultrastructure and growth characteristics of the 10 lines are described. Detailed cytogenetic analysis of the first 4 lines indicates that each is karyotypically unique, with no evidence of cross-contamination. Nine of the 10 cell lines secrete immunoreactive beta human chorionic gonadotrophin (beta-hCG) in the culture medium. No correlation was demonstrated between the ability of the cell lines to secrete plasminogen activator and their capacity to grow in soft agar or as xenografts in immune-deficient mice.

Some mechanisms of local bone destruction by squamous carcinomas of the head and neck

An in vitro osteolysis assay with 45Ca-labelled mouse calvaria has been used to investigate mechanisms of direct bone invasion by squamous carcinomas of the head and neck. Short-term (3-day) organ cultures of 8 fresh squamous carcinomas showed varying degrees of in vitro bone-resorbing activity which was blocked by indomethacin, an inhibitor of prostaglandin synthesis. Supernatant media from 6 established cell lines also induced bone resorption in vitro and evoked an osteoclastic response in the cultured calvaria. Osteolysis by supernatant media was not blocked by indomethacin in all the tumour-cell lines, and the production of non-prostaglandin osteolysins by the indomethacin-resistant lines is postulated. The two principal findings that emerge are: (1) Stimulants for osteoclastic activity are derived from both squamous-carcinoma cells and from host cells in the tumour stroma. (2) These stimulants are diverse. Indomethacin-sensitive agents, presumed to be prostaglandins, are most convincingly demonstrated in the fresh tumours. Indomethacin-resistant agents, presumably not prostaglandins, are more characteristic of the carcinoma cell lines.

An unexpected fungal infection in a patient with leukaemia

A 58-year-old man, who was entering remission from acute monocytic leukaemia, died unexpectedly after five days of fever. Cultures of necropsy material grew the yeast Trichosporon beigelii, and subsequent histological examination showed a widely disseminated infection. This fungus usually causes a localised lesion of the hair shaft (piedra). Deep-seated infections due to Trichosporon spp. have been recorded infrequently and disseminated infections on only five previous occasions. None of these has been from the United Kingdom. This case report describes some of the difficulties of diagnosis.

The irradiated radical neck dissection in squamous carcinoma: a clinico-pathological study

A preliminary clinico-pathological survey is presented of radical neck dissections from 50 patients with advanced (T3, T4) squamous carcinomas of the head and neck, previously treated by irradiation and combination chemotherapy. The total yield of lymph nodes (1411) from these dissections was high--mean of 28 nodes/dissection, range 8-60; the proportion of nodes containing metastatic carcinoma was low--100 (7%)--with only 1 or 2 nodal masses/dissection in most instances. The involved nodes tended to be concentrated in 1 or 2 anatomical groups, principally in the upper anterior neck, with apparent sparing of nodes in the posterior triangle. There was a high incidence (88%) of transcapsular spread. Keratin granulomas, with or without intact metastatic carcinoma, were commonly found; on occasions they formed large masses simulating nodal metastases. The morphological patterns in uninvolved lymph nodes were shown to be of no prognostic significance. Initial data on postoperative follow-up indicated a crude survival of 52% (24 patients) at 30 months. Most deaths (80%) occurred within 12 months of major surgery; the majority (72%) died with residual malignant disease; and uncontrolled primary tumour, particularly in the oral cavity and oropharynx, was found more frequently than metastatic disease in the neck or elsewhere. Clinical implications are discussed with reference to the use of modified radical neck dissection in the surgical salvage of this poor-risk group of previously irradiated patients.

Direct bone invasion in squamous carcinomas of the head and neck: pathological and clinical implications

Direct bone invasion by tumour--an uncommon event at most sites--has been demonstrated in 18 out of 150 consecutive major surgical specimens from patients with squamous carcinomas of the head and neck. Intra-oral carcinomas invading the jaw(s) comprise the single commonest group. The tumour gains access to bone by direct spread or along perineural spaces: infiltration of periosteal lymphatics was rare. The morphological phases of bone invasion are described, the main feature being bone destruction by osteoclasts in front of the advancing tumour; tumour cells do not directly impinge on the bone surface until the late stages of invasion. Osteoblastic activity is less marked. Evidence that osteoclasts are directly stimulated by local tumour is discussed. The clinical implications relate to the possible uses of scintigraphy and the need to ensure adequate bone resections in operable lesions: the tumours sometimes infiltrate laterally beneath apparently intact bone cortex (cf. submucosal spread), and the normal tissue planes at the bone-soft tissue interface are usually distorted by previous radiotherapy.

Prostaglandin-like material extracted from squamous carcinomas of the head and neck

Tumour-associated prostaglandin-like material, assessed by bioassay, has been examined in 37 patients with primary and metastatic squamous carcinomas of the head and neck, previously treated by radiotherapy and chemotherapy followed by radical surgery. High amounts of prostaglandin-like material were extracted from tumours excised within 3 months of radiotherapy and chemotherapy. These amounts correlated with necrosis, inflammation and fibrosis, but not with tumour site, size or degree of differentiation. Most of the prostaglandins formed by these treated tumours thus seem to be associated with host stromal and inflammatory cells, rather than the neoplastic cells. The possible roles of prostaglandins in facilitating the spread of squamous carcinomas are discussed.

Natural antibodies to EBV-VCA antigens in common marmosets (Callithrix jacchus) and response after EBV inoculation

Healthy common marmosets from two separate colonies, one in England and one in France, were found to have antibodies cross-reacting with Epstein-Barr virus structural antigens (EBV-VCA). All seropositive animals were at least 2 years old. Experimental EBV infection of marmosets of different ages led to seroconversion of inoculated weanlings. Adult animals either developed antibody for the first time or showed an increase in their existing titers. Both control and infected animals developed a progressive interstitial nephritis. The lymphocytic infiltration was more extensive, diffuse and immature in appearance in inoculated animals, but no definite evidence of lymphoproliferative disease or lymphoma was found.

Perineural spread in squamous cell carcinomas of the head and neck: a clinicopathological study

Perineural spread of tumour has been demonstrated in 24% of an unselected series of 70 patients with squamous carcinomas of the head and neck treated by surgery. Slightly more than half the patients had primary tumours arising within the buccal cavity. Clinical features suggesting perineural infiltration were found in about two thirds of the cases; the symptoms and signs were usually sensory and occurred early in the disease. The mandibular division of the trigeminal nerve was most commonly affected. Perineural spread was more likely to occur with large carcinomas, moderate or poorly differentiated, showing local invasion and lymph node metastases. The associated pathological changes are described and a high incidence of damage to nerve fibres is recorded. The practical implications of perineural spread of tumour are discussed with reference to indications for more radical surgery or for more conservative measures supplemented with other modes of treatment.

Local invasion by laryngeal carcinoma--the importance of focal (metaplastic) ossification within laryngeal cartilage

Patterns of cartilage invasion by squamous carcinoma were examined in 34 consecutive laryngectomy specimens with particular reference to selective involvement of ossified cartilage. Direct infiltration of the laryngeal framework was demonstrated in 17 cases--16 (out of 17) transglottic carcinomas and in a simgle example of a combined glottic and infraglottic tumour. The susceptibility of ossified laryngeal cartilage to tumour invasion was confirmed, and morphological studies ahve clarified the underlying mechanisms. Invasion is a largely indirect process dominated by local bone destruction by osteoclasts, operating in front of the advancing tumour. One established, carcinoma cells infiltrate and erode bone alone, and the osteoclasts disappear. Reasons for the particular susceptibility of ossified laryngeal cartilage to tumour invasion are discussed and attention is drawn to the role of the tumour-associated osteoclast activating factors such as postaglandins. Therapeutic implications of cartilage invasion are noted.

Changes in tight junctions of rat intestinal crypt cells associated with changes in their mitotic activity

The freeze-fracture appearance of tight junctions between rat duodenal crypt cells was studied in normal, mitotically suppressed, and mitotically enhanced animals. In normal animals crypt cell tight junctions present a pleomorphic appearance. The population includes junctions resembling postmitotic junctions of the intestinal villus, junctions composed largely or completely of particle chains, and regions at the cell apex in which junctions are absent for 3-4 micron distances laterally. Mitotic suppression by inhibition of DNA synthesis with cytosine arabinoside results in the disappearance of pleomorphism and crypt tight junctions progressively come to resemble those of the intestinal villus. With recovery from the drug and further synchronization with Colcemid, the crypt cells undergo a mitotic burst, and all varieties of unusual junctional configurations are observed with increased frequency.

An ultrastructural investigation of nephrotoxicity in rats induced by feeding cultures of Penicillium verrucosum var. cyclopium

A renal tubular lesion was induced in male rats by giving them a culture homogenate or culture filtrate of Penicillium verrucosum var. cyclopium by gastric gavage for 20 days. The fungus was obtained from stored maize in an area of endemic nephropathy in Bulgaria. Changes in the proximal convoluted tubules were studied by light and electron microscopy. The lesion was confined to the pars recta in the outer stripe of the outer zone of the medulla. It consisted of degeneration and necrosis of epithelial cells, prominent karyomegaly, arrested mitotic divisions and production of binucleate and tetranucleate tubular cells. Two patterns of degeneration occurred with comparable frequency: a vesicular form with pyknotic nucleus and electron lucent degeneration. Nuclei of the epithelial cells in affected tubules contained segregated nucleoli. The necrotic cells were replaced by actively regenerating cells derived from adjacent viable epithelium. The similarity between the tubular lesions induced in rats and the changes found in patients with Balkan endemic nephropathy is discussed.

Pharyngeal rhabdomyoma: an unusual presentation

A case of pharyngeal rhabdomyoma is reported with the unusual presenting symptom of haemoptysis. After complete excision of the lesion, the(71-year-old) patient remained tumour-free until his death from heart disease 19 months later. Seven other published cases of pharyngeal rhabdomyoma are reviewed together with 27 other reported extracardiac adult rhabdomyomas which, with a single exception, occurred in the head and neck region.

Metastatic potential of malignant tumours

The term 'metastatic potential' is examined, together with some of the factors that may contribute to it. The evidence is drawn from clinical and experimental sources. Morphological factors include the site of the tumour, its size, histological appearances and pattern of local spread. The scope and limitations of each are discussed and the potential application of newer morphological techniques is noted. Certain non-morphological factors are considered: these are (1) the functional heterogeneity of tumour cell populations with resepct to the metastatic capacity; (2) the elaboration of certain tumour-associated products which may potentiate tumour spread; and (3) immunological factors in the form of local host cell infiltrates in and around primary tumours. The tumour-associated products include collagenases, prostaglandins and angiogenesis factor; their likely origin from tumour and host cells is stressed, together with their implications in physiological and pathological processes other than neoplasia. It is concluded that the metastatic potential of tumours cannot be assessed in the terms of conventional tumour pathology alone. A more functional approach is needed before the term 'metastatic potential' acquires solid conceptual or practical value.

The immunological response of CBA mice to P. yoelii. I. General characteristics, the effects of T-cell deprivation and reconstitution with thymus grafts

Experimental infection of normal CBA mice with the parasite Plasmodium berghei yoelii (P. yoelii) resulted in a mild, non-fatal and self-limiting infection which lasted for 15-17 days. Animals which recovered from the primary infection were immune to reinfection though parasites could be detected in the kidneys of such mice 4 weeks after recovery from infection. (No plasmodia were demonstrated in the peripheral blood and other tissues examined.) In T cell-deprived mice, P. yoelii infections resulted in a progressive parasitaemia and proved fatal in 35-40 days. Studies of fluorescent antibody levels and morphological changes in the spleens of infected normal and T cell-deprived mice showed that while normal mice produced high levels of IgG1, IgG2 and IgM antiplasmodial antibodies and developed a strong and sustained germinal centre response, in T cell-deprived animals the production of IgG1 antibodies was almost completely abolished and the germinal centre response severely impaired. Reconstitution of T cell-deprived mice with syngeneic thymus grafts resulted in partial restoration of immunological responsiveness. P. yoelii infections in these reconstituted animals ran a self-limiting course akin to that seen in normal CBA mice; the level of protective immunity and the germinal centre response correlated with the degree of reconstitution achieved.

Balkan (endemic) nephropathy and a toxin-producing strain of Penicillium verrucosum var cyclopium: An experimental model in rats

Cultures of an isolate of Penicillium verrucosum var. cyclopium, obtained from stored maize in an area of Balkan (endemic) nephropathy--Vratza, Bulgaria--has consistently induced renal tubular lesions when force-fed to rats for 20 days. The lesions, confined to the lower reaches of the proximal convoluted tublues (pars recta and junctional zone), closely resemble the tubular changes in patients with Balkan nephropathy. Preliminary evidence suggests that this nephrotoxin-producing strain of P. verrucosum var. cyclopium may be implicated in the aetiology of Balkan nephropathy.