Apolipoprotein E4 promotes the early deposition of Abeta42 and then Abeta40 in the elderly

The apolipoprotein Eepsilon4 allele (ApoEepsilon4) is associated with a selective increase in deposition of the 40-amino acid form of the beta-amyloid peptide (Abeta40) in endstage Alzheimer's disease. To determine how apoE genotype affects the early events in beta-amyloid pathogenesis, we analyzed the medial temporal lobes of 244 elderly persons who were not clinically demented using antibodies selective for the C termini of Abeta40 and Abeta42. We found that: (1) the number of both Abeta42- and Abeta40-positive senile plaques increase with age; (2) Abeta42 appears at younger ages, and in more amyloid deposits, than does Abeta40 in all ApoE groups; (3) when compared at similar ages, older persons with ApoEepsilon4 are more likely to have Abeta42- and Abeta40-immunoreactive deposits than are persons without ApoEepsilon4; (4) Abeta40-containing plaques arise at least a decade later than do Abeta42 plaques, and are seldom found in the medial temporal lobe of older persons lacking ApoEepsilon4; and (5) in the absence of overt Alzheimer's disease, cerebral amyloid angiopathy is rare in the elderly, but in our sample was significantly augmented in ApoEepsilon4 homozygotes. We conclude that ApoEepsilon4 hastens the onset of Abeta42 deposition in the senescent brain, which in turn fosters the earlier evolution of fibrillar, Abeta40-positive plaques, thereby increasing the risk of Alzheimer's disease.

[Symptomatic Langerhans-cell-histiocytosis of the cervical spine in a child: case report]

We report on a six year old female presented with a painful torticollis and a hemidysaesthesia caused by destruction of the third cervical vertebra and a paravertebral soft-tissue mass. At diagnostic routine finally a biopsy gives the diagnosis of Langerhans cell histiocytosis. In a second open approach the destructed vertebral body was replaced by a precisely adjusted autologous bone interponate and the patient was maintained in halo vest immobilisation. The outcome is described and an overview of the current literature is given.

Prevalence, morphology and biology of renal cell carcinoma in von Hippel-Lindau disease compared to sporadic renal cell carcinoma

PURPOSE

Renal cell carcinoma occurs as a sporadic tumor but may be part of the autosomal dominant von Hippel-Lindau disease, characterized by retinal and central nervous system hemangioblastoma, pheochromocytoma, pancreatic cysts and renal cell carcinoma. We determine the prevalence of von Hippel-Lindau disease in a series of unselected renal cell carcinoma cases by molecular genetic analysis, and compare sporadic to von Hippel-Lindau renal cell carcinoma with respect to morphology and biology.

MATERIALS AND METHODS

We established registers comprising 63 subjects with von Hippel-Lindau renal cell carcinoma, belonging to 30 distinct families (register A), and 460 unselected patients operated on for renal cell carcinoma in an 11-year period (register B). Molecular genetic analysis of the von Hippel-Lindau gene was performed for living patients of register A, representing 80% of von Hippel-Lindau families, and register B, 62% living patients, to identify von Hippel-Lindau germline mutations. In addition, register B was evaluated by a questionnaire (95% response) for familial occurrence of von Hippel-Lindau disease.

RESULTS

The prevalence of von Hippel-Lindau renal cell carcinoma was 1.6% in 189 consenting unselected renal cell carcinoma patients. Risk factors for occult germline von Hippel-Lindau gene mutations in register B included familial renal cell carcinoma in 3 of 3 patients (100%), multifocal or bilateral renal cell carcinoma in 1 of 10 (10%) and age younger than 50 years at diagnosis in 1 of 33 (3%). Compared to sporadic von Hippel-Lindau renal cell carcinoma was characterized by an occurrence 25 years earlier, association with renal cysts, multifocal and bilateral tumors, cystic organization and low grade histology, and a better 10-year survival (p < 0.001 each). In von Hippel-Lindau disease metastases occurred only in tumors larger than 7 cm.

CONCLUSIONS

von Hippel-Lindau differs from sporadic renal cell carcinoma in morphology and biology. Our data provide arguments for planning surgery for von Hippel-Lindau renal cell carcinoma and should stimulate future investigations.

Intravascular lymphoma presenting as symmetric polyarthritis

Intravascular lymphoma (IVL) is an uncommon neoplastic disorder characterized by monoclonal intravascular expansion of lymphoid cells. Occlusion of small vessels in various organ systems probably accounts for the broad clinical spectrum of this type of lymphoma, which can closely mimic a variety of diseases, especially vasculitic disorders, and thus lead to delayed clinical diagnosis. This is the first report of a patient who presented with a predominant symptom of symmetric polyarthritis accompanied by fever. While her initial systemic symptoms, such as fever, improved rapidly after initiation of corticosteroid therapy, the response of the polyarthritic joint manifestations was only transient. The patient died of progressive lung involvement and was diagnosed as having IVL by histologic analysis of tissue samples obtained postmortem.

Apolipoprotein E4 promotes incipient Alzheimer pathology in the elderly

To evaluate the influence of the apolipoprotein E (ApoE) epsilon4 allele on the age at which Alzheimer-like lesions appear in the brain, we analyzed the degree of cerebral beta-amyloidosis and neurofibrillary tangle formation in the hippocampal formation and adjacent cortical areas 28, 27, and 36 of persons who had died between the ages of 50 and 93 years and who had shown no signs of clinical dementia. The occurrence of the three common polymorphisms of the ApoE gene in this sample of 147 routine autopsy cases from eastern Germany was comparable to previously reported values in European and North American populations: ApoEepsilon2/2, 0.7%; ApoEepsilon2/3, 14.3%; ApoEepsilon2/4, 4.1%; ApoEepsilon3/3, 56.5%; ApoEepsilon3/4, 22.4%; and ApoEepsilon4/4, 2.0%. Nondemented persons carrying the ApoEepsilon4 allele were significantly more likely to have senile plaques, diffuse amyloid deposits, cerebrovascular amyloid, and neurofibrillary tangles than were those lacking E4. Comparing the two largest ApoE subgroups, ApoEepsilon3/3 and ApoEepsilon3/4, the relative increase in the occurrence of beta-amyloid in the epsilon3/4 group was evident by the mid-60s, with the relative increase in neurofibrillary tangles in this group emerging slightly earlier. The ApoEepsilon2 allele appears to delay the appearance of the lesions somewhat. We conclude that ApoEepsilon4 promotes the early appearance of beta-amyloid and neurofibrillary tangles in the elderly and that the increased frequency of these lesions is related to the higher risk of Alzheimer disease in persons bearing the ApoEepsilon4 allele.

Loss of heterozygosity in the tuberous sclerosis (TSC2) region of chromosome band 16p13 occurs in sporadic as well as TSC-associated renal angiomyolipomas

Angiomyolipomas (AMLs) are renal tumors that occur both sporadically and in association with tuberous sclerosis (TSC). TSC is an autosomal dominant disorder characterized by hamartomatous lesions in multiple organs. Two TSC loci are recognized: TSC1 on 9q34 and TSC2 on 16p13. Loss of heterozygosity (LOH) at the TSC1 and TSC2 loci in lesions from TSC patients has recently been reported. Lesions that are not associated with TSC have not been previously examined for LOH at the TSC loci. We analyzed 29 renal angiomyolipomas from patients without a history of TSC. Three tumors demonstrated LOH on 16p13. This is the first report indicating that mutations in TSC2 occur in tumors of patients who do not have TSC. We also found LOH on 16p13 in 5 of 8 TSC-associated AMLs. Two of these tumors were from a single patient and demonstrated different regions of LOH. These findings support the hypothesis that the TSC2 gene functions as a tumor suppressor.

[Defects in the immunoglobulin producing cells in bone marrow of patients with variable immunodeficiency syndrome]

The number of plasma cells, IgG+, IgA1+, IgA2+ and IgM+ cells were determined in bone marrow (BM) biopsies of 12 patients with common variable immunodeficiency syndrome (CVID) and 12 controls without signs of immunodeficiency. Controls had a median of 11 plasma cells/mm2, 76 IgG+, 76 IgA+ and 18 IgM+ cells/mm2 BM, respectively. Compared with the control group, the CVD patients showed a significant reduction of each cell type (p < 0.001). They also demonstrated a close correlation between low numbers of IgG+ and IgA+ cells in the BM and low IgG and IgA serum levels. In general, there was also a good correlation of the IgM+ cells and the respective IgM levels in the serum, except 2 CVID patients with normal IgM serum levels and subnormal numbers of IgM+ cells in the BM. Our results showed that there was an almost complete coincidence between the reduced numbers of Ig-producing cells in the BM and low serum levels of the respective Ig isotype. Thus, immunohistological analysis may be of additional help for the diagnosis of immunodeficiency.

[T-cell rich B-cell lymphoma: diagnosis, differential diagnosis, and classification of two representative cases]

Two post mortem examinations from the Institute of Pathology, Albert-Ludwigs-University of Freiburg, will be presented. In both cases diagnosis of a T-cell-rich B-cell-lymphoma was first established after necropsy and evaluation of the immunohistochemical results. In the first case a peripheral T-cell-lymphoma was diagnosed after a peripheral T-cell-marker test. A liver biopsy showed suspicion of a Hodgkin-lymphoma. In the second case a biopsy of an extended retroperitoneal tumor showed a centroblastic non-Hodgkin-lymphoma 3 weeks before death. By autopsy we found in both cases a wide infiltration with small monomorphic lymphocytes. Less than 20% of the infiltrate consisted of polymorphous blasts with a wide morphologic range and prominent nucleoli. Immunohistochemistry showed the blasts to be CD20-positive, while the small monomorphic lymphocytes expressed the CD3 marker. In the first case kappa-light-chain-restriction was shown in the blasts by immunohistochemistry. Differential diagnosis difficulties, diagnostic criteria, prognosis and classification of these cases in the common non-Hodgkin-lymphoma classification will be discussed in view of the current literature.

Invasive pulmonary aspergillosis. MRI, CT, and plain radiographic findings and their contribution for early diagnosis

A prospective study was conducted in 38 patients with nodular lesions on plain chest radiographs and the clinical suspicion of invasive pulmonary aspergillosis (IPA) to assess the diagnostic accuracy of magnetic resonance imaging (MRI) and computed tomography (CT). For early diagnosis of IPA (clinical signs and symptoms < 10 days), CT scans with demonstration of the halo sign had a high sensitivity (16/22) and specificity (8/8). Magnetic resonance imaging performed at the same time revealed a relatively higher sensitivity (22/22), but a very poor specificity (0/8). Gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA) enhanced images did not improve specificity. In the later course of infection (clinical signs and symptoms > 10 days), MRIs showed typical nodular target-like lesions with Gd-DTPA enhancement of the rim area that was not seen in the early course of the disease or in patients with Pseudomonas or staphylococcal infection. In conclusion, MRI findings are not as characteristic as the CT halo sign in diagnosing IPA in the early course of the disease, but the MRI target sign with Gd-DTPA enhancement of the rim area and the "reverse target" on T2-weighted images are strongly suggestive of IPA at a later stage of the disease.

[Radiologic differential diagnosis of inflammatory round pulmonary infiltrates in immunocompromised patients. A prospective study using CT and MRT]

In a prospective study we examined the diagnostic ranking of CT and MR in 52 immunocompromised patients with nodular pulmonary lesions and clinical suspicion of invasive pulmonary aspergillosis (IPA). For early diagnosis of IPA (clinical symptoms having existed for less than 10 days) the CT halo sign proved highly sensitive and specific. MRT showed at this time a comparatively high sensitivity but only low specificity that could not be improved upon after Gd-DTPA. At a later stage of the aspergillosis infection (clinical symptoms manifested for more than 10 days) MR identified aspergillus-specific lesions with on-target characteristics (marked enhancement of margins after Gd-DTPA) or the so-called "reverse" target phenomenon (T2-weighted sequences). Such lesions were never seen in the early stage of the disease in patients with nodular pulmonary lesions of different aetiology (pseudomonal or staphylococcal pneumonia).

Intravascular lymphoma simulating vasculitis

The case history of a patient with intravascular lymphoma (IL) is reported. Signs of a systemic illness including fever, muscular weakness, telangiectasias, nephrotic syndrome, and neurologic manifestation suggested vasculitis. Cyclophosphamide treatment produced almost complete remission, but the patient died of respiratory failure 13 months after presentation due to lung involvement. The diagnosis was not revealed until postmortem examination. The differential diagnosis of IL is provided.

[Differential diagnostic aspects of lethal midline granulomas (granuloma gangraenescens]

The lethal midline granuloma and limited Wegener's granulomatosis show clinical similarity, although they are of different etiology. The following case of a 53-year-old woman shows how difficult it is to establish the precise diagnosis of lethal midline granuloma. The diagnosis depends on the pathological finding of a lymphoma. The lymphoma can be differentiated in a T- or a B-cell lymphoma by immunostaining. However, the diagnostic yield of biopsies from the nose is not perfect. It would be, therefore, important to find other diagnostic criteria. The presence of the c-ANCA is a helpful tool, but in the case of limited Wegener's granulomatosis, it has a sensitivity of 50%. The prognosis of the lethal midline granuloma is poor even if an adequate radiation therapy is instituted.

[Immunohistochemical characterization of the intestinal immune system of patients with AIDS]

Lamina propria mononuclear cells in duodenal and colonic biopsies of AIDS patients and controls were immunohistologically studied for T-cells (CD3), IgA1+, IgA2+, IgM+, IgG2+, IgG4+ and J-chain-positive cells. In AIDS patients, there was a decrease of IgA1+ (p = 0.0009), IgA2+ (p = 0.011), IgM+ (p = 0.018), IgG4+ (p = 0.0002) cells in the duodenum. In the colonic biopsies, IgA2+ (p = 0.0001) and IgG2+ (p = 0.0372) cells were also decreased, whereas the IgM+ cells were increased (p = 0.0023). Relative numbers of J-chain-expressing cells of the small and large intestine were not different from controls (p = 0.373; p = 0.0618). The number of T-cells was reduced in duodenal and colonic biopsies (p = 0.0002; p = 0.0030). The presented results are compatible with the assumption of a functional B-cell defect of the intestinal immune system. The decrease of Ig-producing cells in the intestine contrasts with the increased levels of serum Ig in AIDS patients, indicating that the GALT is a particular compartment of the immune system.

Intestinal B cell defects in common variable immunodeficiency

The humoral immune system of the small intestine of 17 patients with common variable immunodeficiency (CVID) was studied by immunohistology using antibodies specific for IgA1,2, IgM, IgG1-4, the J chain and the secretory component (SC). IgA1,2+, IgG2+ and IgM+ lamina propria B cells were totally lacking in 65% (11/17), 41% (7/17) and 18% (3/17) of CVID patients, respectively. One patient exhibited an isolated IgA1 subclass deficiency. The proportion of plasma cells in conventionally stained histological sections of the same intestinal biopsies showed a close correlation with the numbers of IgA+ and IgM+ cells. Considerable numbers of J chain-synthesizing cells were present in all patients with CVID, indicating the presence of early B cells unable to differentiate into immunoglobulin-producing plasma cells. Most of the patients with intestinal IgA and/or IgM defects strongly expressed the SC in their enterocytes, suggesting an immunoglobulin-independent regulation of the SC. Clinically, only CVID patients with intestinal IgA defects developed intestinal infections with Giardia lamblia, Campylobacter jejuni or Candida albicans. The outcome of in vitro immunoglobulin synthesis assays with peripheral blood lymphocytes did not predict the presence or absence of the respective isotype-producing B cells in the intestinal lamina propria. Thus, immunohistological examinations of intestinal biopsies are required to determine the extent of mucosal immunodeficiency in CVID patients.

[Extensive pulmonary tumor embolisms of anaplastic thyroid gland carcinoma as a rare cause of hemorrhagic pleural effusion in an 88-year-old patient]

An 88 year old woman without substantial previous illness was admitted to hospital because of a rapidly developing dyspnea and thoracic pains. X-Ray, CT scan and ultra sound showed a subdivided pleural effusion of the left side. After a short time a pulmonary infiltrate as well as a contralateral pleural effusion developed. Neither tumor cells nor mycobacteria could be detected in repeated pleural punctions. The general condition of the patient was deteriorating continuously while an antibiotic therapy given in the meantime only led to a temporary recovery. Three weeks later the patient died under the picture of a cardio-respiratory failure. At autopsy the lungs showed parenchymal haemorrhages and multiple infarctions as well as pleural effusions. The above mentioned changes could be explained histologically by tumor embolism of small pulmonary arteries from an anaplastic thyroid carcinoma. The discussion gives a short survey about already published cases of tumor embolism in the lung. PMVC as the diagnostic method of choice is discussed.

Transjugular intrahepatic portosystemic stent-shunt (TIPS) in the treatment of Budd-Chiari syndrome

Budd-Chiari syndrome is characterized by splanchnic congestion due to obstruction of the hepatic venous outflow. A variety of treatment modalities have limited applicability due to their invasive nature, complications or low effectivity. The transjugular intrahepatic portosystemic stent-shunt (TIPS) offers a new treatment by creating an intraparenchymal duct between a main branch of the portal vein and hepatic vein i.e. the intrahepatic part of the inferior vena cava. This paper describes the treatment of two patients with fulminant and subacute Budd-Chiari syndrome treated 2 days and 2 months after the onset of clinical symptoms. It demonstrates that TIPS is a feasible treatment of Budd-Chiari syndrome that restores splanchnic blood flow, reduces collateral circulation and ascites and provides sufficient time to allow for elective liver transplantation, if indicated. Further studies are required to evaluate the effect of TIPS on liver function and survival.

[Reduced "oxidative burst" in a granulocyte subpopulation in a case of Sweet syndrome]

Oxidative burst was defective in 50% of peripheral blood neutrophils in a case of Sweet syndrome with leukemoid granulocytosis. Phagocytosis was normal. We suggest that the decreased ability to produce oxygen radicals observed in this patient might lead to a compensatory recruitment of hematopoietic growth factors. Consecutive activation, increased chemotaxis and adhesion of polymorphonuclear granulocytes might be the cause of the neutrophilic dermal infiltrate of Sweet syndrome.

Parthenogenetic stem cells in postnatal mouse chimeras

The ability of parthenogenetic (pg) cells to contribute to proliferating stem cell populations of postnatal aggregation chimeras was investigated. Using DNA in situ analysis, pg participation was observed in highly regenerative epithelia of various regions of the gastrointestinal tract, e.g., stomach, duodenum and colon, in the epithelia of tongue and uterus and in the epidermis. Pg cells also contributed to the epithelium of the urinary bladder, which is characterized by a relatively slow cellular turnover. Using a sensitive proliferation marker to determine division rate of pg and normal (wt) cells in tissues of a 24-day-old chimera, no significant differences between pg and fertilized cells were observed. However, in colon and uterus of a pg &lt;==&gt; wt chimera aged 101 days, a significant loss of proliferative capacity of pg cells was found. In the colon, this loss of proliferative potential was accompanied by an altered morphology of pg crypts. In general, they were situated at the periphery of the epithelium and lacked access to the lumen, with consequent cystic enlargement and flattened epithelium. No obvious morphological changes were observed in the pg-derived areas of the uterine epithelium of this chimera. Our results provide evidence that pg cells can persist as proliferating stem cells in various tissues of early postnatal chimeras. They suggest that pg-derived stem cells may cease to proliferate in restricted areas of the gastrointestinal tract and in the uterine epithelium of pg &lt;==&gt; wt chimeras of advanced age.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary thymic carcinoid with Cushing's syndrome

In a 52-year-old Caucasian man osteopoikilosis had been misdiagnosed roentgenologically 2 years before his death. Gradually he developed Cushing's syndrome and ultimately superior vena caval obstruction. At autopsy a primary thymic carcinoid with extensive osteoblastic bone metastasis was found. Immunohistochemically the tumor was shown to be positive for adrenocorticotropic hormone (ACTH), cytokeratin (KL1), neuron-specific enolase, synaptophysin, chromogranin and glucagon. Remarkably the tumour was negative for serotonin despite high urinary hydroxyindolacetic acid levels. Bilateral hyperplasia of the adrenal cortex was found. The adenohypophysis showed a considerable reduction of ACTH-producing cells and numerous Crooke's cells with a characteristic immunohistochemical pattern.

[Gastroenterologic findings in graft versus host disease after allogenic bone marrow transplantation]

We are reporting on a 25 years old patient with acute myelogenous leukemia, who developed an acute graft-versus-host disease (GVHD) 43 days after allogeneic bone marrow transplantation (BMT). The clinical symptoms included exanthema, diarrhea and abdominal cramps. The patient was treated with cyclosporine A and prednisone and the clinical symptoms disappeared subsequently. At day 225 post BMT the patient became icteric as the clinical manifestation of chronic GVHD. We describe in this case report endoscopical and histological findings during the episodes of acute and chronic graft-versus-host disease. The results obtained by sigmoidoscopy and liver biopsy confirmed the clinical diagnosis. The clinical work up of patients with acute or/and chronic GVHD should also include sigmoidoscopy in order to verify this transplantation related complication.

[Primary pulmonary hypertension and pregnancy]

Primary pulmonary hypertension (PPH) is an uncommon disease with a poor prognosis. Most patients with PPH are young women of child-bearing age. We report on such a case of PPH during pregnancy, discuss the aetiology, pathophysiology, morphological characteristics and the management in pregnancy and delivery.

Adoptive transfer of the hematopoietic system of trisomic mice with limited life span: stem cells from six different trisomies are capable of survival

The life span of murine trisomies is limited to the fetal or early postnatal period. However, rescue of the hematopoietic system of fetal mice with trisomies (Ts) 12, 13, 14, 16, 18, and 19 is possible by transplanting hematopoietic stem cells from the liver into lethally irradiated adult hosts. Thus, radiation chimeras with permanent and almost complete trisomic hematopoietic and lymphocytopoietic systems were constructed. The longest documented survival of a trisomic graft was 12 months in Ts 19 chimeras. Blood counts in trisomic chimeras reveal a marked anemia in Ts 16 chimeras; lymphocytopenia in Ts 12, Ts 16, and Ts 19 chimeras; and granulocytopenia in Ts 18 chimeras. Survival rates of Ts 12, Ts 18, and Ts 19 chimeras were not different from those of the respective controls, whereas survival rates of chimeras with Ts 13 and Ts 16 hematopoiesis were markedly reduced and that of Ts 14 chimeras only slightly reduced. These results indicate that transplanted hematopoietic stem cells from Ts 13, Ts 14, and Ts 16 fetuses exhibit relevant genetically determined defects, resulting in a reduced restoration capacity of hematopoietic organs and/or deficiencies of differentiated blood cells.

[Renal artery aneurysm in Wegener's granulomatosis]

Microaneurysms of renal and visceral arteries are characteristic signs of periarteritis nodosa. Normally they are not found in Wegener's disease, where glomerulonephritis is commonly observed. We report on a patient with vasculitis of the upper and lower respiratory tract, focal glomerulonephritis, prostatic and pulmonary granulomas and anti-cytoplasm antibodies corresponding to Wegener's disease. The most striking findings in angiography were multiple small aneurysms of the peripheral branches of the renal artery. At necroscopy these angiographic findings were histologically proven as necrosis of the arterial wall with destruction of the elastic lamina, causing local vascular ectasia. These renal vascular changes are a characteristic sign of periarteritis nodosa. The combination of clinical, laboratory, radiologic and histologic findings in our patient can be explained as an overlap-syndrome of Wegener's disease and periarteritis nodosa. We assume that the combination of pathologic findings in our patient correspond to a rare atypical renal manifestation of Wegener's disease.

[Primary manifestation of Wegener's granulomatosis of the prostate]

In approximately 2-7% of patients with Wegener's granulomatosis involvement of the prostate has been demonstrated histologically. This usually comes about quite late in the course of disease, after generalization of the granulomatous vasculitis from respiratory tract to kidneys and other organs. The patient we present had a highly atypical first manifestation of Wegener's granulomatosis in the prostate, generalized vasculitis not developing until later. When a biopsy shows unclear granulomatous changes in the prostate, a test for anticytoplasmatic antibodies should be performed in addition to the conventional serologic and cultural examinations. Anticytoplasmatic antibodies are highly specific for the diagnosis of active Wegener's granulomatosis. Early diagnosis and immediate initiation of immunosuppressive therapy with cyclophosphamide and corticosteroids can prevent or limit organ damage and improve the prognosis in Wegener's granulomatosis.

[An unusual slow course of systemic vasculitis with multiorgan involvement]

This paper reports on an unusually slowly progressing course seen in systemic vasculitis of the median and smaller arteries and small veins associated with dermatomyositis, chronically active hepatitis, glomerulonephritis of the immune complex and restrictive cardiomyopathy in a 35-year-old patient. The authors discuss the difficulties in establishing the diagnosis and in finding the exact classification of this disease.

[Therapy of amyloid nephrosis in Crohn disease: plasmapheresis plus azathioprine?]

A 38-year old woman with serious nephrotic syndrome due to kidney amyloidosis in consequence of Crohn's disease was observed. The long-term prognosis of this illness is serious, but since in the literature several good results have been mentioned under treatment with immunosuppressives, in the present case an aggressive immunosuppression was carried out, which was started under the conception that, in consequence of elimination of preamyloid substances from the serum by plasmapheresis in combination with an additional inhibition of the reproduction of these substances by azathioprine, the clinical picture could be favourably influenced. During therapy with long-term intermittent plasmapheresis in combination with azathioprine a complete remission of the nephrotic syndrome was achieved.

Degeneration and atrophy of the thymus of lethally irradiated dogs, rescued by transfusion of cryopreserved autologous blood leukocytes

Dogs exposed to a fatal radiation dose of 12 Gy were rescued by transfusion of autologous blood leukocytes. A severe acute and long-lasting damage to the thymus was observed. The acute damage, as observed on the tenth day, consisted of a marked reduction in the number of lymphocytes, degeneration of Hassall's bodies, and hemorrhage. Long-term effects, observed several months after irradiation, were partial to total atrophy of the thymus. Regeneration, when it occurred, was limited to a few small isolated areas in which lymphopoiesis was supported by epithelial reticular cells. In contrast, the lymph nodes of all dogs had abundant cortical lymphopoiesis. The abundant hemopoiesis present in the marrow from the tenth day after irradiation until the end of the observation period should have provided sufficient circulating precursor cells to seed the thymus and regenerate the organ to the same extent as that observed in the other blood-forming organs. The impairment of lymphopoietic regeneration in the thymus seems to be due, therefore, to damage caused by irradiation on the specific stroma of the organ, which is not able to support such activity.

Susceptibility of mice reconstituted with trisomy 19 hematopoietic cells to infection with Rauscher leukemia virus

Radiation chimeras with trisomy 19 hematopoietic cells were constructed to test the sensitivity of the trisomic hematopoietic system to infection with Rauscher leukemia virus: Hematopoietic cells from livers of trisomic fetuses were rescued by transplantation into lethally irradiated adult mice. These Ts 19 radiation chimeras show a stable and sufficiently long-lived trisomic hematopoiesis to allow experimental induction of Rauscher leukemia. Rauscher leukemia virus (RLV) induced a marked proliferation of erythroblasts in the spleens of Ts 19 mice and control chimeras within 3 weeks. The onset of erythroblast proliferation was significantly delayed in the Ts 19 mice, suggesting a smaller number of target cells for the RLV and/or reduced susceptibility of the target cells to RLV. Both Ts 19 and control chimeras developed nonlymphocytic leukemia 2-4 months after RLV injection. The course of leukemogenesis was similar in the two experimental groups. No numerical chromosome abnormalities associated with leukemogenesis were detectable in Ts 19 or control cells. The numbers of chromosomal sister chromatid exchanges 2 weeks after RLV injection were elevated to the same degree in both Ts 19 and control cells. Thus, cells with constitutional trisomy do not show increased chromosomal instability due to leukemogenesis.

Multifocal dermal-type basal cell adenomas of parotid glands with co-existing dermal cylindromas

A basal cell adenoma of the parotid gland accompanied by multiple developing microadenomas of the same type and three dermal cylindromas, all observed in a 54-year-old woman, were examined by light microscopy. The histological structure of the basal cell adenomas shows striking similarities to co-existing dermal cylindromas, suggesting a common histogenesis of both tumors. We suggest that the term "basal cell adenoma of dermal type" should be used for these lesions. Multifocal ductal proliferations with nascent adenomas in the glandular parenchyma allow us to trace the development of these tumors. Studies of the literature reveal four additional cases in which there are co-existing basal cell adenomas of salivary glands and dermal adnexal tumors.

Murine trisomy: developmental profiles of the embryo, and isolation of trisomic cellular systems

Many questions related to the development and the phenotypic expression of trisomy (Ts) are amenable to systematic investigation in a mouse model that allows the induction of Ts 1 to 19 by a breeding design of mice heterozygous for Robertsonian metacentric chromosomes. Some Ts do not survive the first critical phase of organogenesis on days 11 to 12 of fetal development; others as Ts 12, 14, 16, 18, and 19, have a life span until or beyond birth. Model type studies of the morphogenesis of developmental anomalies (e.g. craniocerebral, cardiovascular, or placental) are possible in Ts with a longer developmental span, and Ts 16 of the mouse is considered as a natural model of human trisomy 21. The eventual breakdown and death of the trisomic organism are inevitable. There is considerable interest to find ways for rescue and longer survival of Ts in competitive developmental systems, as e.g., in Ts in equilibrium with 2n blastocyst chimeras, or by isolation of trisomic cellular or tissue systems. Thus, the transfer of Ts hemopoietic stem cells of the fetal liver to irradiated adult recipients is a means of studying the functional capacities and maturation of trisomic hemopoiesis and lymphopoiesis. Both are almost completely restored by Ts 12, 14, 18, and 19 stem cell transplantation with survival periods of more than 6 months. But in other Ts, as of chromosomes 13 or 16, such capacity of reconstitution is impaired. The stepwise analysis of the effects of chromosome triplication on the cell level, in isolated functional systems and in the embryonic organism, is a promising way to understand the phenotypic expression of genome anomalies in complex developmental processes.

Relevance of trisomy 15 and other chromosome abnormalities in spontaneous AKR leukemia of mice with and without Robertsonian rearrangement

The types and frequencies of chromosomal abnormalities in spontaneous AKR leukemia are presented: 45% to 58% of leukemic animals exhibit chromosome abnormalities; trisomy of chromosome 15 (Ts 15) occurs as the predominant chromosome abnormality not only in AKR/J but also in two AKR sublines characterized by the presence of two or one Robertsonian biarmed translocation Rb (6.15) of the chromosomes 6 and 15. Most often a triplication of the whole Rb (6.15) is found in Rb (6.15) homozygotes corresponding to combined Ts 6 + Ts 15. In the Rb (6.15) heterozygotes both trisomy of the biarmed (6.15) and of the acrocentric 15 is observed. Centric fission of the (6.15) chromosome is also possible in Rb (6.15) homozygotes resulting in Ts 15 without simultaneous Ts 6. Trisomies of other chromosomes are found either in addition to Ts 15 or as the only abnormality. If the data of Dofuku et al. (1975) are considered, abnormal karyotypes in AKR leukemia show Ts 15 in 90%, Ts 12 and Ts 17 in 18%-20%, and Ts 3, Ts 10 and Ts 14 in 8%-10% of the cases.

Chromosome rearrangements involved in the origin of trisomy 15 in spontaneous leukemia of AKR mice

Trisomy 15, known to be the predominant chromosome abnormality in leukemic cells of the AKR strain, develops even in animals of the subline AKR/Rb1Ald with two constitutive Robertsonian translocation chromosomes (6.15). Among 10 leukemic animals of this subline exhibiting chromosomal anomalies, 6 showed trisomy of the whole Robertsonian translocation chromosome with the expression of combined trisomy 6 and 15 as the most frequent abnormality. Besides this, rearrangements were observed in five animals, most of them resulting from centric fission of the Rb(6.15) translocation chromosome. Trisomy 15 with two Rb(6.15) and an extra acrocentric 15 was found in 44% of spleen cells in one animal, and a new Rb translocation of chromosomes 11 and 15 was seen in 50% of spleen and thymus cells of another animal. In both cases trisomy 15 without simultaneous trisomy 6 resulted. Thus, the triplication of a whole Rb(6.15) is frequent in leukemic AKR/Rb(6.15)1Ald, and ensuing double trisomy 6 + 15 is tolerated by the leukemic cell. But the development of trisomy 15 combined with centric fission of Rb(6.15) without simultaneous trisomy 6 is another principle realized in leukemogenesis.

Trisomic hemopoietic stem cells of fetal origin restore hemopoiesis in lethally irradiated mice

Autosomal trisomy in the mouse is invariably associated with fetal or early postnatal death. Hemopoietic stem cells from fetuses trisomic for chromosome 12 or 19 can be rescued by transplantation into lethally irradiated mice. These trisomic cells restore hemopoiesis, including lymphopoiesis, in the irradiated mice and establish a permanent and almost complete engraftment. There is no evidence that hemopoietic cells with trisomy 12 or 19 are cytogenetically unstable.

Collection of in vitro colony-forming units from dogs by repeated continuous flow leukaphereses

The presence of in vitro colony-forming units (CFUc) was demonstrated in leukocyte suspensions collected by continuous flow leukaphereses performed serially in dogs. The CFUc yield of one leukapheresis was usually between 10(4) and 10(6). Higher yields were obtained in the 2nd to 5th leukaphereses than in the first one in the same dog. The number of CFUc collected during one leukapheresis was about four times the number of CFUc present in the circulating blood at the beginning of the leukapheresis. After a diminution during leukapheresis the circulating CFUc pool was restored in 2 or 3 days with an increase in the ratio of CFUc to mononuclear cells. These results indicate that CFUc entered the circulating pool during and after leukapheresis and that the population size regulation of canine-circulating CFUc is different from that of the bulk of the mononuclear leukoytes.

Regeneration of blood-forming organs after autologous leukocyte transfusion in lethally irradiated dogs. I. Distribution and cellularity of the bone marrow in normal dogs

Marrow cellularity in adult beagles (1-2 yr old) is highest in centrally located bones, with values between 8000 and 12,000 nucleated cells per sq mm. It decreases gradually towards the peripheral parts of the body, reaching values below 1000 per sq mm in bones distal to the elbow and knee. The first tail segment always contains some active marrow. The fifth segment has only stromal elements. In spongy bones fat cells appear to be distributed at random among the blood-forming elements. In the middle part of the femur the fatty marrow predominates in the center of the cylinder, while the subendosteal area is very cellular. The proximal and distal ends of the femur are more cellular than the middle. The small standard deviation of the cellularity in the spongy bones of the trunk and in the proximal and middle part of the humerus makes these sites areas of choice for quantitative studies of marrow regeneration. The large variations in cellularity of the marrow in the radius and tibia of young adult dogs make these sites unsuitable for such studies. The distribution of active and fatty marrow in dogs is similar to that of humans. The differential count of active marrow is quite constant between different dogs and in the various sites of each animal.

[Collection of hematopoietic stem cells from canine peripheral blood and their ability to regenerate hematopoiesis]

A procedure is presented for the collection of a large number of hemopoietic stem cells from the peripheral blood of dogs by means of a single leukapheresis using the NCI-IBM Blood Cell Separator. In the course of a leukapheresis of about 285 min duration a mean of 23 x 10-9 leukocytes is collected from the blood. The hemopoietic stem cells among such separated leukocytes initiate repopulation of bone marrow within 10 days after whole body X-irradiation with 1200 R. The cell numbers in a defined histological section of femoral bone marrow are evaluated 9 to 10 days after irradiation and subsequent autologous transfusion of 6.72 x 10-9 separated mononuclear leukocytes. The results indicate that the bone marrow cell numbers of transfused dogs are significantly greater than in dogs given only 1200 R and reach a level of approximately 49% of the normal value. Possible ways of increasing the yield of hemopoietic stem cells from the peripheral blood will be considered.