Current Progress of Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) Vaccine Development

SFTSV is an emerging tick-borne virus causing hemorrhagic fever with a case fatality rate (CFR) that can reach up to 27%. With endemic infection in East Asia and the recent spread of the vector tick to more than 20 states in the United States, the SFTSV outbreak is a globally growing public health concern. However, there is currently no targeted antiviral therapy or licensed vaccine against SFTSV. Considering the age-dependent SFTS pathogenesis and disease outcome, a sophisticated vaccine development approach is required to safeguard the elderly population from lethal SFTSV infection. Given the recent emergence of SFTSV, the establishment of animal models to study immunogenicity and protection from SFTS symptoms has only occurred recently. The latest research efforts have applied diverse vaccine development approaches-including live-attenuated vaccine, DNA vaccine, whole inactivated virus vaccine, viral vector vaccine, protein subunit vaccine, and mRNA vaccine-in the quest to develop a safe and effective vaccine against SFTSV. This review aims to outline the current progress in SFTSV vaccine development and suggest future directions to enhance the safety and efficacy of these vaccines, ensuring their suitability for clinical application.

Self-assembling Gn head ferritin nanoparticle vaccine provides full protection from lethal challenge of Dabie Bandavirus in aged ferrets

Dabie Bandavirus (DBV), previously known as Severe Fever with Thrombocytopenia Syndrome (SFTS) Virus, induces a characteristic thrombocytopenia with a mortality rate ranging from 12% to as high as 30%. The sero-prevalence of DBV in healthy people is not significantly different among age groups, but clinically diagnosed SFTS patients are older than ~50 years, suggesting that age is the critical risk factor for SFTS morbidity and mortality. Accordingly, our immune-competent ferret model demonstrates an age (>4 years old)-dependent DBV infection and pathogenesis that fully recapitulates human clinical manifestation. To protect the aged population from DBV-induced SFTS, vaccine should carry robust immunogenicity with high safety profile. Previous studies have shown that glycoproteins Gn/Gc are the most effective antigens for inducing both neutralizing antibody (NAb)- and T cell-mediated immunity and, thereby, protection. Here, we report the development of a protein subunit vaccine with 24-mer self-assembling ferritin (FT) nanoparticle to present DBV Gn head region (GnH) for enhanced immunogenicity. Anion exchange chromatography and size exclusion chromatography readily purified the GnH-FT nanoparticles to homogeneity with structural integrity. Mice immunized with GnH-FT nanoparticles induced robust NAb response and T-cell immunity against DBV Gn. Furthermore, aged ferrets immunized with GnH-FT nanoparticles were fully protected from DBV challenge without SFTS symptoms such as body weight loss, thrombocytopenia, leukopenia, and fatality. This study demonstrates that DBV GnH-FT nanoparticles provide an efficient vaccine efficacy in mouse and aged ferret models and should be an outstanding vaccine candidate targeted for the aged population against fatal DBV infection.

SFTSV Gn-Head mRNA vaccine confers efficient protection against lethal viral challenge

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne virus, causing thrombocytopenia and hemorrhagic fever, with a fatality rate ranging from 12% to 30%. SFTSV possesses Gn and Gc glycoproteins, which are responsible for host cell receptor attachment and membrane fusion, respectively, to infect host cells. We have previously reported a protein subunit vaccine candidate (sGn-H-FT) of the SFTSV soluble Gn head region (sGn-H) fused with self-assembling ferritin (FT) nanoparticles, displaying strong protective immunogenicity. In this study, we present messenger RNA (mRNA) vaccine candidates encoding sGn-H or sGn-H-FT, both of which exhibit potent in vivo immunogenicity and protection capacity. Mice immunized with either sGn-H or sGn-H-FT mRNA lipid nanoparticle (LNP) vaccine produced strong total antibodies and neutralizing antibodies (NAbs) against sGn-H. Importantly, NAb titers remained high for an extended period. Finally, mice immunized with sGn-H or sGn-H-FT mRNA LNP vaccine were fully protected from a lethal dose of SFTSV challenge, showing no fatality. These findings underscore the promise of sGn-H and sGn-H-FT as vaccine antigen candidates capable of providing protective immunity against SFTSV infection.

Self-assembling Gn head ferritin nanoparticle vaccine provides full protection from lethal challenge of Dabie bandavirus in aged ferrets

IMPORTANCE

Dabie bandavirus (DBV) is an emerging tick-borne virus that causes severe fever with thrombocytopenia syndrome (SFTS) in infected patients. Human SFTS symptoms progress from fever, fatigue, and muscle pain to the depletion of white blood cells and platelets with fatality rates up to 30%. The recent spread of its vector tick to over 20 states in the United States increases the potential for outbreaks of the SFTS beyond the East Asia. Thus, the development of vaccine to control this rapidly emerging virus is a high priority. In this study, we applied self-assembling ferritin (FT) nanoparticle to enhance the immunogenicity of DBV Gn head domain (GnH) as a vaccine target. Mice immunized with the GnH-FT nanoparticle vaccine induced potent antibody responses and cellular immunity. Immunized aged ferrets were fully protected from the lethal challenge of DBV. Our study describes the GnH-FT nanoparticle vaccine candidate that provides protective immunity against the emerging DBV infection.

Glucosylceramide is essential for Heartland and Dabie bandavirus glycoprotein-induced membrane fusion

Due to climate changes, there has been a large expansion of emerging tick-borne zoonotic viruses, including Heartland bandavirus (HRTV) and Dabie bandavirus (DBV). As etiologic agents of hemorrhagic fever with high fatality, HRTV and DBV have been recognized as dangerous viral pathogens that likely cause future wide epidemics. Despite serious health concerns, the mechanisms underlying viral infection are largely unknown. HRTV and DBV Gn and Gc are viral surface glycoproteins required for early entry events during infection. Glycosphingolipids, including galactosylceramide (GalCer), glucosylceramide (GlcCer) and lactosylceramide (LacCer), are a class of membrane lipids that play essential roles in membrane structure and viral lifecycle. Here, our genome-wide CRISPR/Cas9 knockout screen identifies that glycosphingolipid biosynthesis pathway is essential for HRTV and DBV infection. The deficiency of UDP-glucose ceramide glucosyltransferase (UGCG) that produces GlcCer resulted in the loss of infectivity of recombinant viruses pseudotyped with HRTV or DBV Gn/Gc glycoproteins. Conversely, exogenous supplement of GlcCer, but not GalCer or LacCer, recovered viral entry of UGCG-deficient cells in a dose-dependent manner. Biophysical analyses showed that GlcCer targeted the lipid-head-group binding pocket of Gc to form a stable protein-lipid complex, which allowed the insertion of Gc protein into host lysosomal membrane lipid bilayers for viral fusion. Mutagenesis showed that D841 residue at the Gc lipid binding pocket was critical for GlcCer interaction and thereby, viral entry. These findings reveal detailed mechanism of GlcCer glycosphingolipid in HRTV and DBV Gc-mediated membrane fusion and provide a potential therapeutic target for tickborne virus infection.

Viral codon optimization on SARS-CoV-2 Spike boosts immunity in the development of COVID-19 mRNA vaccines

Life-long persistent herpesviruses carry "trans-inducers" to overcome the unusual codon usage of their glycoproteins for efficient expression. Strikingly, this "trans-inducibility" can be achieved by simply changing the codon-usage of acute virus glycoproteins to that of persistent herpesvirus glycoproteins with herpesviral trans-inducer. Here, we apply the "persistent viral codon-usage-trans-inducer" principle to SARS-CoV-2 Spike mRNA vaccine platform, in which the codon-usage of Spike is changed to that of Herpes Simplex Virus-1 (HSV-1) glycoprotein B (gB) with its "trans-inducer" ICP27. The HSVgB-ICP27-codon-optimized Spike mRNA vaccine induced markedly high antigen expression and stability, total IgG, neutralizing antibody, and T cell response, ultimately enhancing protection against lethal SARS-CoV-2 challenge. Moreover, the HSVgB- codon-optimized Delta (B.1.617.2) strain Spike mRNA vaccine provided significant enhancements in antigen expression and long-term protection against SARS-CoV-2 challenge. Thus, we report a novel persistent viral codon-usage-trans-inducer mRNA vaccine platform for enhanced antigen expression and long-term protection against lethal viral infection.

High-Level Ciprofloxacin-Resistant Campylobacter jejuni Isolates Circulating in Humans and Animals in Incheon, Republic of Korea

Campylobacter jejuni is one of the major causative pathogens of outbreaks or sporadic cases of diarrhoeal diseases worldwide. In this study, we compared the phenotypic and genetic characteristics of C. jejuni isolates of human and food-producing animal origins in Korea and examined the genetic relatedness between these two groups of isolates. Regardless of isolation source, all C. jejuni isolates harboured four virulence genes, cadF, cdtB, ciaB and racR, whereas the wlaN and virB11 genes were more frequently observed in human isolates. Antimicrobial susceptibility testing showed that the majority of C. jejuni isolates displayed high-level resistance to fluoroquinolone (95.2%) or tetracycline (76.2%) antibiotics, and 12.4% of isolates exhibited multidrug resistance (more than three classes of antibiotics tested). Pulsed-field gel electrophoresis (PFGE) of all Campylobacter isolates revealed 51 different SmaI-PFGE patterns and six major clusters containing both human and animal isolates. These results indicate that genetically diverse strains of C. jejuni with antimicrobial drug-resistance and virulence properties have prevailed in Incheon. Nevertheless, some particular populations continue to circulate within the community, providing the evidence for an epidemiological link of C. jejuni infections between humans and food-producing animals. Therefore, the continued monitoring and surveillance of C. jejuni isolates of human and food-producing animal origins are required for public health and food safety.

Localized prostate cancer: effect of hormone deprivation therapy measured by using combined three-dimensional 1H MR spectroscopy and MR imaging: clinicopathologic case-controlled study

PURPOSE

To determine the accuracy of combined magnetic resonance (MR) imaging and three-dimensional (3D) proton MR spectroscopic imaging in localizing prostate cancer to a sextant of the gland in patients receiving hormone deprivation therapy.

MATERIALS AND METHODS

Combined MR imaging/3D MR spectroscopic imaging examinations were performed in 16 hormone-treated patients and 48 nontreated matched control patients before radical prostatectomy and step-section histopathologic analysis. At MR imaging, cancer presence within the peripheral zone was assessed on a per sextant basis by two readers. At 3D MR spectroscopic imaging, cancer was identified by using (choline plus creatine)-to-citrate ratios at cutoff values of 2 and 3 SDs above mean normal peripheral zone values. Data were compared by using receiver operating characteristic analysis.

RESULTS

There was no significant difference in the ability of combined MR imaging/3D MR spectroscopic imaging to localize prostate cancer in treated versus control patients. For MR imaging alone, the sensitivity and specificity were 91% and 48% (reader 1) and 75% and 60% (reader 2) in treated patients versus 79% and 60% (reader 1) and 84% and 43% (reader 2) in control patients. For 3D MR spectroscopic imaging alone (>3 SDs cutoff), higher specificity (treated, 80%; controls, 73%) but lower sensitivity (treated, 56%; controls, 53%) was attained. In treated patients, high sensitivity or specificity (up to 92%) was achieved when either or both modalities indicated cancer.

CONCLUSION

When performed within 4 months after initiating hormone deprivation therapy, combined MR imaging/3D MR spectroscopic imaging had the same accuracy in localizing prostate cancer as in nontreated patients.

Genetic changes in paired atypical and usual ductal hyperplasia of the breast by comparative genomic hybridization

PURPOSE

Breast cancer is thought to develop from noninvasive precursor lesions, although the earliest steps of neoplastic transformation are still undefined. Usual ductal hyperplasia (UDH) is considered to represent a benign proliferation of ductal epithelial cells, whereas atypical ductal hyperplasia (ADH) may represent the first clonal neoplastic expansion of these cells. The aim of this study was to examine genetic alterations in UDH and ADH and to determine the relationship between these lesions in the same breast biopsy.

EXPERIMENTAL DESIGN

Comparative genomic hybridization analysis was used to define copy number alterations in DNA extracted from archival sections of 18 patients. Nine patients showed ADH with adjacent UDH, and nine showed pure UDH. None showed evidence of invasive cancer or ductal carcinoma in situ.

RESULTS

Five of the nine ADH lesions showed chromosome copy number alterations. 16q loss (five cases) and 17p loss (two cases) were the most frequent changes. The associated UDH lesions in these five patients also showed copy number alterations, always a subset of the changes present in the paired ADH. In one other patient, the UDH showed eight chromosomal alterations, whereas the paired ADH showed no changes. Only one of nine cases with pure UDH showed comparative genomic hybridization abnormalities.

CONCLUSIONS

These data support the likelihood that UDH is a precursor of ADH, at least in some cases representing neoplastic growth. The frequencies of 16q and 17p losses suggest that alterations of candidate genes located in these chromosomal regions may play a role early in breast carcinogenesis.

Desmoplastic small round cell tumor presenting as a neck mass: a case report

An unusual case study of a desmoplastic small round cell tumor presenting as a 3.5-cm, firm, supraclavicular neck mass and diagnosed by fine-needle aspirate biopsy in a 16-yr-old male is reported. Clinical, cytologic, and immunocytochemical findings are described. Histologic, immunohistochemical, and genetic features are discussed. Desmoplastic small round cell tumor should be considered in the differential diagnosis of small round cell tumors of any site; the importance of ancillary studies in arriving at the correct diagnosis is emphasized.

Impaired spermatogenesis in men with congenital absence of the vas deferens

It is generally assumed that men with congenital bilateral absence of the vas deferens (CBAVD) have azoospermia because of obstruction and that sperm production is normal. This study examines spermatogenesis in men with CBAVD to assess the validity of this assumption. We identified all men with CBAVD who had undergone either a diagnostic or therapeutic fertility procedure. Procedures included diagnostic biopsy, testis fine needle aspiration (FNA) mapping, microscopic epididymal sperm aspiration (MESA), and testis sperm extraction (TESE). Among 33 CBAVD men, 18 underwent testis biopsy, 27 had MESA/TESE, and 10 had FNA mapping. On evaluation of these procedures, normal spermatogenesis was present in 29 men. Four men (12%) demonstrated impaired spermatogenesis. One patient had FNA testis cytology consistent with late maturation arrest, another demonstrated hypospermatogenesis on biopsy and low sperm yield by MESA, and two patients had pure Sertoli cell only histology on biopsy. Aetiologies for impaired spermatogenesis included varicocele and underlying genetic abnormalities. Although patients with CBAVD are assumed to have normal spermatogenesis and infertility due simply to obstruction, the potential for concomitant defects in sperm production exists. A clinical suspicion of testis failure should prompt further diagnostic evaluation of spermatogenesis prior to sperm retrieval. In addition, genetic counselling should be offered and testing for genetic lesions, including cystic fibrosis gene mutations and/or variants, Y chromosome microdeletions, and karyotype abnormalities, should be considered.

Testicular fine-needle aspiration in infertile men: correlation of cytologic pattern with biopsy histology

Open testicular biopsy is the standard method for histopathologic assessment of spermatogenesis. The need for testis biopsy has been questioned with the increased success of minimally invasive techniques such as fine-needle aspiration (FNA) mapping. This study examines whether FNA can provide cytologic information equivalent to histologic patterns by correlating diagnoses from testis FNA cytology with biopsy histology. Men (n = 87) who had undergone both diagnostic FNA mapping and open testis biopsy in the evaluation of infertility were identified. Biopsies were assessed by recognized histologic patterns of normal, hypospermatogenesis, early and late maturation arrest, and Sertoli cell only. FNA cytologic specimens were examined for adequacy and were classified similarly. Mixed patterns were also identified. The correlation between the two methods was 94%, with no differences among the different histologies. Discrepancies between cytology and histology were primarily the result of inadequate sampling and evidence of mixed patterns on FNA mapping. FNA cytology is a minimally invasive method of obtaining testicular tissue for diagnostic purposes. These data demonstrate that FNA cytology can evaluate accurately all classically defined histologic types, and may have the potential to replace testis biopsy in the assessment of spermatogenesis.

Relationship between classic histological pattern and sperm findings on fine needle aspiration map in infertile men

Systematic testis fine needle aspiration (FNA) mapping has been proposed as an adjunctive or alternative diagnostic procedure to biopsy to determine the presence of spermatozoa within infertile testes. This study related testis histology to the global presence or absence of spermatozoa in the same testes determined by FNA cytology. Testis biopsies and FNA mapping were performed in 87 infertile, azoospermic men. A mean of 1.3 biopsies and 14 FNA sites were taken per patient. Biopsies were assessed by recognized histological patterns of normal, Sertoli cell-only, hypospermatogenesis, early and late maturation arrest, sclerosis as well as mixed patterns that included at least two of these histologies. FNA cytological specimens were assessed for sperm presence by an experienced cytologist. Overall, spermatozoa were found by FNA mapping in 52% of patients. A comparison of histology and FNA findings revealed that pure patterns of Sertoli cell-only and early maturation were associated with a very poor likelihood of sperm detection (4-8%). In contrast, patients with other pure pattern histologies or mixed patterns had high rates of FNA sperm detection (77-100%). Similar to reported testicular sperm extraction (TESE) findings, sperm detection with FNA shows wide variation depending on testis histology. Unlike most TESE reports, however, some histological patterns generally reflect a more global testicular dysfunction and poorer likelihood of sperm identification, suggesting the possibility that these phenotypes have a genetic origin. Systematic testis sampling with FNA offers additional geographical information about spermatogenesis that routine biopsies lack and can further guide couple decision-making in severe male factor infertility.

Diagnostic findings from testis fine needle aspiration mapping in obstructed and nonobstructed azoospermic men

PURPOSE

Although helpful for defining extratesticular obstruction, the testis biopsy offers limited information on nonobstructive azoospermic testes. Guided by diagnostic biopsies, testis sperm extraction procedures fail in 25% to 50% of patients with nonobstructive azoospermia, largely because it is clinically difficult to know where sperm are located. To provide a more complete assessment of spermatogenesis in nonobstructive azoospermic patients and to simplify the confirmation of sperm production in men with obstruction, we use a systematic, fine needle aspiration "mapping" procedure. We summarize the diagnostic findings in a series of azoospermic men.

MATERIALS AND METHODS

From 118 azoospermic infertile men (22 with obstructed and 96 with nonobstructed azoospermia) fine needle aspiration data were used to generate location specific, sperm frequency maps for obstructed and nonobstructive azoospermic testes to determine if "sperm rich" locations existed.

RESULTS

Fine needle aspiration map analysis revealed that all aspiration locations from obstructed cases showed sperm. In men with nonobstructive azoospermia, sperm was identified in the right testis in 134 of 652 (20.5%) and in the left testis in 151 of 716 (21.1%) separate aspirations. Rates of sperm detection among various intratesticular sites were not statistically different. In 27.1% of cases the fine needle aspiration map found sperm in men with sperm negative biopsies. The likelihood of heterogeneity in fine needle aspiration sperm findings was 25% within individual nonobstructive azoospermic testes and 19.2% between testis sides. At post-procedure followup of 88 patients (74%), no clinical or surgical complications were observed.

CONCLUSIONS

Testis fine needle aspiration mapping is a simple, reliable and informative diagnostic tool in the evaluation of azoospermic infertile men.

Compound genetic factors as a cause of male infertility: case report

A 40 year old healthy Chinese male with primary infertility was seen in a university male infertility and genetic counselling clinic. He presented with congenital bilateral absence of the vas deferens (CBAVD) and the finding of testis atrophy. Fine needle aspiration mapping of the testis identified and localized sperm production within the testicles for in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Careful evaluation of testicular cytology revealed late maturation arrest of spermatogenesis. Cystic fibrosis gene mutation analysis revealed heterozygosity for the 5T variant within the polypyrimidine tract of intron 8. Cytogenetic analysis revealed a pericentric inversion of chromosome 6 with break points at p12 and q21 [46,XY,inv(6)(p12q21)]. This case illustrates that spermatogenesis is not necessarily normal with congenital bilateral absence of the vas deferens. Compound genetic defects may coexist and underlie male infertility.

Angiomyolipoma of the liver in fine-needle aspiration biopsies: its distinction from hepatocellular carcinoma

BACKGROUND

Angiomyolipoma (AML) of the liver is an uncommon benign lesion that may be difficult to distinguish clinically, radiographically, and morphologically from hepatocellular carcinoma (HCC).

METHODS

Fine-needle aspiration biopsies (FNAB) of three AMLs of the liver were compared with FNABs from eight cases of HCC. Immunoperoxidase stains for HMB-45, muscle specific actin, and CAM 5.2 were performed on two cell blocks and one resection of AML.

RESULTS

All three AMLs yielded cellular aspirates. They were composed of clusters of cells with arborizing transgressing endothelium but no peripherally wrapping endothelium. Smooth muscle cells of AML showed fibrillar cytoplasm and indistinct cytoplasmic borders; HCC showed granular cytoplasm and distinct cytoplasmic borders. Extramedullary hematopoiesis was present only in AML. Mitotic figures were seen only in HCC. Intranuclear inclusions, nucleoli, and large, atypical cells were present in both AML and HCC. Fat was seen in only one case of AML and was scant. Immunoperoxidase stains for HMB-45 and smooth muscle actin were positive in AML and negative in adjacent normal liver. CAM 5.2 stain was negative in AML.

CONCLUSIONS

The cytologic features seen on FNABs of AML are distinct from those of HCC. Immunoperoxidase stains can aid in the definitive diagnosis on FNAB. It is important to recognize AML on FNAB to allow conservative clinical management.

Fine needle aspiration cytology of dermatopathic lymphadenitis

OBJECTIVE

Dermatopathic lymphadenitis (DL) can be a nonneoplastic cause of an enlarged lymph node or nodes. Cytologic findings of DL have not been well described. The differential diagnosis includes Langerhans histiocytosis (LH) in children and low grade lymphoma in adults. We present three cases of dermatopathic lymphadenitis with a discussion of cytologic findings and differential diagnosis.

STUDY DESIGN

Fine needle aspiration (FNA) findings of three cases of lymph nodes involved by DL were reviewed. All three were axillary lymph nodes in patients with skin rashes. Immunoperoxidase stains for S-100 and CD1a were performed on a cell block from one case, and flow cytometric analysis was performed on another.

RESULTS

FNA of DL yields cellular smears with abundant histiocytoid cells with moderate cytoplasm and ovoid, vesicular nuclei with longitudinal grooves (interdigitating reticulum cells). These histiocytoid cells are S-100 and CD1a positive. The background cells are mature lymphocytes, scattered eosinophils and plasma cells. Case 1 was originally misinterpreted as consistent with LH. In case 2, flow cytometric analysis of a mixed population of lymphocytes was seen, ruling out lymphoma. In case 3, the diagnosis of DL was based on morphologic features.

CONCLUSION

Interdigitating reticulum cells in dermatopathic lymphadenitis are S-100 and CD1a positive and could be confused with LH in children. In adults, flow cytometry could be used to distinguish them from low grade lymphoma. FNA findings of DL should be interpreted with the clinical history.

Riedel's thyroiditis presenting with hypothyroidism and hypoparathyroidism: dramatic response to glucocorticoid and thyroxine therapy

Riedel's thyroiditis is a rare fibro-inflammatory process originating in the thyroid gland with progressive extension and invasion of surrounding tissues. Patients frequently present with a stony hard thyroid mass suggestive of anaplastic carcinoma. We report a striking case of Riedel's thyroiditis associated with hypothyroidism, hypoparathyroidism and bilateral vocal cord paralysis. A dramatic response to high dose prednisone and levothyroxine therapy was seen, with recovery of parathyroid and vocal cord function. Our case suggests that early initiation of combination therapy may be important, particularly in the presence of severe disease.

Systematic fine-needle aspiration of the testis: correlation to biopsy and results of organ "mapping" for mature sperm in azoospermic men

OBJECTIVES

This study compares fine-needle aspiration (FNA) and testis biopsy for the ability to detect mature sperm in the testes of azoospermic men. In addition, we introduce the concept of testis "mapping" with FNA and apply it to detect sperm in men with severe testis failure.

METHODS

Sixteen patients were evaluated for azoospermia in a university-based infertility clinic. All men had testis biopsies and FNAs from matched testicular sites to assess for the presence of spermatozoa. Adequacy criteria for FNA specimens were strictly defined, and correlative analysis of the two techniques was performed. In addition, a subset of 12 men with nonobstructive azoospermia (NOA) had systematic FNA mapping (more than four FNA sites per testis) to detect mature sperm for potential clinical use.

RESULTS

Adequate FNA specimens were obtained in 115 (91.3%) of 126 FNA attempts. Of 34 paired biopsy FNA sites. FNA was seen to be more sensitive than, and equally specific as, testis biopsy for sperm detection. When compared with the biopsy touch imprint, FNA was equally as sensitive and specific. Among men with NOA who underwent FNA mapping, 4 (33%) of 12 had localized "patches" of sperm detected in areas distant from sperm-negative biopsy sites. In 1 case, a pregnancy was achieved with later biopsy and sperm extraction "directed" by previous FNA.

CONCLUSIONS

For sperm detection, testis FNA provides equivalent or better information than a testis biopsy. FNA can localize areas of sperm production within the testis and accurately guide sperm extraction procedures in men with NOA.

Fetal congenital cystic adenomatoid malformations of the lung: a clinicopathologic study of eleven cases

We describe the pathological examination of 11 cases of fetal congenital cystic adenomatoid malformation of the lung. All patients were treated in utero between 21 and 27 weeks of gestation with either lobectomy or placement of a thoracoamniotic shunt. Ten cases involved a single lobe, and one case involved two lobes. The lesions contained both solid and cystic areas. On the basis of microscopic appearances, we separated the malformations into two distinct types. The first type consisted of seven cases showing scattered bronchiole-like dilated spaces lined by pseudostratified ciliated epithelium with intervening tightly packed small tubules lined by columnar cells with subnuclear vacuoles. This pattern superficially resembled the pseudoglandular period of lung development. The remaining four cases were of the other histologic type. They contained scattered bronchiole-like structures with intervening irregularly branching glands lined by cuboidal epithelium within loose mesenchymal stroma. This pattern superficially resembled the canalicular period of lung development. We observed that the malformations contained cysts of various sizes and that cyst size varied widely within a single lesion. Moreover, predominantly cystic and predominantly solid lesions could not be separated histologically. Thus, we identify two patterns of fetal congenital cystic adenomatoid malformations, pseudoglandular and canalicular, the clinical significance of which is yet to be determined.

Low-grade lymphoma of mucosa-associated tissue in the parotid gland: a case report of fine-needle aspiration cytology diagnosis using flow cytometric immunophenotyping

A 66-year-old woman with Sjögren's syndrome for 7 years presented with an enlarged right parotid gland. The left parotid gland, which showed myoepithelial sialadenitis (MESA), had been resected 4 years earlier. A fine-needle aspiration (FNA) biopsy of the right parotid gland was performed. Examination of the smears revealed cells of intermediate size with a round-to-irregular nuclear outline and distinct pale cytoplasm intermixed with small mature round lymphocytes. The chromatin was slightly paler and less clumped than in small mature lymphocytes. A small inconspicuous nucleolus was seen in most of the cells. Flow cytometry immunophenotyping performed on the FNA biopsy material showed a monoclonal population of B cells with kappa light chain restriction. The cytomorphology coupled with the immunophenotyping study in this clinical context suggested the diagnosis of low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). Extensive staging work-up revealed no evidence of disseminated disease. The right parotid gland was surgically excised. Histology and gene rearrangement studies confirmed the cytologic diagnosis. To our knowledge, this is the first description of a low-grade lymphoma of MALT in a salivary gland to be diagnosed by FNA.

A case of composite Hodgkin's disease and chronic lymphocytic leukemia in bone marrow. Lack of Epstein-Barr virus

We report Hodgkin's disease arising in a 68-year-old patient with a history of chronic lymphocytic leukemia for 8 years. The patient presented with a 4-month history of weakness, loss of appetite, and a 15-pound weight loss. A bone marrow biopsy showed two distinct histologic types of lymphoma: chronic lymphocytic leukemia and Hodgkin's disease. Immunohistochemical studies showed that chronic lymphocytic leukemia cells were composed of kappa-light chain-restricted monoclonal B cells. The Reed-Sternberg cells expressed CD15. Epstein-Barr virus RNA was not identified in either the Reed-Sternberg cells or cells of chronic lymphocytic leukemia by in situ hybridization. To our knowledge, this is the second reported case of composite Hodgkin's disease and chronic lymphocytic leukemia involving the bone marrow.

Fine-needle aspiration of lymph nodes: use of flow cytometry immunophenotyping

Fine-needle aspiration of lymph nodes can be used successfully in the clinical work-up of lymphadenopathy. The procedure has some limitations, some of which can be overcome by using such ancillary studies as flow cytometry or immunophenotyping. The authors discuss the use of these techniques in establishing definitive diagnosis of the most common and well-recognized lymphadenopathies.

RBFN restoration of nonlinearly degraded images

We investigate a technique for image restoration using nonlinear networks based on radial basis functions. The technique is also based on the concept of training or learning by examples. When trained properly, these networks are used as spatially invariant feedforward nonlinear filters that can perform restoration of images degraded by nonlinear degradation mechanisms. We examine a number of network structures including the Gaussian radial basis function network (RBFN) and some extensions of it, as well as a number of training algorithms including the stochastic gradient (SG) algorithm that we have proposed earlier. We also propose a modified structure based on the Gaussian-mixture model and a learning algorithm for the modified network. Experimental results indicate that the radial basis function network and its extensions can be very useful in restoring images degraded by nonlinear distortion and noise.

Lipopeliosis. An immunohistochemical and clinicopathologic study of five cases

Lipopeliosis is an unusual liver lesion in which sinusoids become engorged by fat globules. It arises in newly transplanted donor livers that display varying degrees of fatty change. If, after transplantation, hepatocyte necrosis secondary to ischemic or preservation injury occurs, the fat escaping the hepatocytes becomes sequestered in the sinusoidal spaces. We previously described this lesion in a case report; we now describe four more cases to define better the incidence, immunohistochemical features, and clinical spectrum. Of 101 transplanted livers, the lesion was noted in five of 28 (18%), with both preservation injury and mild to moderate fatty change present 1 week following transplantation. Factor VIII-related antigen, collagen IV immunoperoxidase, and oil red O stains confirmed the engorgement of sinusoids by fat droplets, and a stain for CD68-positive cells identified a macrophage reaction around the fat droplets. The patient in our original report developed severe graft dysfunction with residual scarring of the centrilobular zone. Two of the four additional cases had no residual side effects from the lipopeliosis; however, two cases were associated with loss of graft. We conclude that lipopeliosis may be fairly common (5% of transplants). Its clinical outcome can vary greatly and most probably depends on the extent of hepatocellular necrosis.