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1.
Clin Immunol ; 266: 110324, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032847

RESUMO

PURPOSE: Histiocytic necrotizing lymphadenitis (HNL) is an inflammatory disease of unknown etiology clinically characterized by painful lymphadenopathy. This study aimed to investigate the role of interferon (IFN)-α in the pathogenesis of HNL and the clinical significance of serum IFN-α levels for the diagnosis and monitoring of HNL disease activity. METHODS: This study enrolled 47 patients with HNL and 43 patients with other inflammatory diseases that require HNL differentiation including malignant lymphoma (ML), bacterial lymphadenitis, and Kawasaki disease. Expression of IFN-stimulated genes (ISGs) and MX1 in the lymph nodes was measured by real-time quantitative reverse transcription polymerase chain reaction and immunofluorescence staining, respectively. Enzyme-linked immunosorbent assay was used to quantify serum cytokine levels. The results were compared with the clinical features and disease course of HNL. RESULTS: Patients with HNL had a significantly elevated ISG expression in the lymph nodes compared with those with ML. MX1 and CD123, a specific marker of plasmacytoid dendritic cells (pDCs), were colocalized. In patients with HNL, serum IFN-α levels were significantly elevated and positively correlated with disease activity. The serum IFN-α level cutoff value for differentiating HNL from other diseases was 11.5 pg/mL. CONCLUSION: IFN-α overproduction from pDCs may play a critical role in HNL pathogenesis. The serum IFN-α level may be a valuable biomarker for the diagnosis and monitoring of disease activity in patients with HNL.

2.
J Clin Immunol ; 44(6): 126, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773000

RESUMO

Alemtuzumab is used with reduced-toxicity conditioning (RTC) in allogeneic hematopoietic cell transplantation (HCT), demonstrating efficacy and feasibility for patients with inborn errors of immunity (IEI) in Western countries; however, the clinical experience in Asian patients with IEI is limited. We retrospectively analyzed patients with IEI who underwent the first allogeneic HCT with alemtuzumab combined with RTC regimens in Japan. A total of 19 patients were included and followed up for a median of 18 months. The donors were haploidentical parents (n = 10), matched siblings (n = 2), and unrelated bone marrow donors (n = 7). Most patients received RTC regimens containing fludarabine and busulfan and were treated with 0.8 mg/kg alemtuzumab with intermediate timing. Eighteen patients survived and achieved stable engraftment, and no grade 3-4 acute graft-versus-host disease was observed. Viral infections were observed in 11 patients (58%) and 6 of them presented symptomatic. The median CD4+ T cell count was low at 6 months (241/µL) but improved at 1 year (577/µL) after HCT. Whole blood cells continued to exhibit > 80% donor type in most cases; however, 3/10 patients exhibited poor donor chimerism only among T cells and also showed undetectable levels of T-cell receptor recombination excision circles (TRECs) at 1 year post-HCT. This study demonstrated the efficacy and safety of alemtuzumab; however, patients frequently developed viral infections and slow reconstitution or low donor chimerism in T cells, emphasizing the importance of monitoring viral status and T-cell-specific chimerism. (238 < 250 words).


Assuntos
Alemtuzumab , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Condicionamento Pré-Transplante , Transplante Homólogo , Humanos , Alemtuzumab/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Masculino , Feminino , Condicionamento Pré-Transplante/métodos , Pré-Escolar , Criança , Lactente , Doença Enxerto-Hospedeiro/etiologia , Estudos Retrospectivos , Povo Asiático , Resultado do Tratamento , Adolescente
3.
BMC Pediatr ; 24(1): 304, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704558

RESUMO

BACKGROUND: T-cell acute lymphoblastic leukemia (T-ALL) tends to involve central nervous system (CNS) infiltration at diagnosis. However, cases of residual CNS lesions detected at the end of induction and post early intensification have not been recorded in patients with T-ALL. Also, the ratio and prognosis of patients with residual intracranial lesions have not been defined. CASE PRESENTATION: A 9-year-old boy with T-ALL had multiple intracranial tumors, which were still detected post early intensification. To investigate residual CNS lesions, we used 11C-methionine (MET)-positron emission tomography. Negative MET uptake in CNS lesions and excellent MRD status in bone marrow allowed continuing therapies without hematopoietic cell transplantation. CONCLUSIONS: In cases with residual lesions on imaging studies, treatment strategies should be considered by the systemic response, direct assessment of spinal fluid, along with further development of noninvasive imaging methods in CNS. Further retrospective or prospective studies are required to determine the prognosis and frequency of cases with residual intracranial lesions after induction therapy.


Assuntos
Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Masculino , Criança , Neoplasias Encefálicas/diagnóstico por imagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Tomografia por Emissão de Pósitrons , Metionina
4.
J Vet Pharmacol Ther ; 47(1): 21-27, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37753811

RESUMO

This study aimed to evaluate the pharmacokinetics (PK) of tranexamic acid (TXA) in horses and estimate its irrelevant plasma and urine concentrations using the pharmacokinetic/pharmacodynamic (PK/PD) approach by applying the Pierre-Louis Toutain model. TXA was intravenously administered to eight thoroughbred mares, and plasma and urine TXA concentrations were quantified by liquid chromatography/tandem mass spectrometry. The quantified data were used to calculate the PK parameters of TXA in horses. The plasma elimination curves were best-fitted to a three-compartment model. Using the Toutain model approach, irrelevant plasma and urine TXA concentrations were estimated to be 0.0206 and 0.997 µg/mL, respectively. The typical values of clearance, steady-state volume of distribution, and steady-state urine-to-plasma ratio were 0.080 L/kg/h, 0.86 L/kg, and 49.0, respectively. The obtained irrelevant concentrations will be useful for establishing relevant regulatory screening limits for effective control of TXA use in horse racing and equestrian sports.


Assuntos
Líquidos Corporais , Esportes , Ácido Tranexâmico , Cavalos , Animais , Feminino , Ácido Tranexâmico/farmacocinética , Ácido Tranexâmico/uso terapêutico , Cromatografia Líquida/veterinária
5.
J Pediatr Hematol Oncol ; 45(2): e285-e289, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36757045

RESUMO

Artemis deficiency is characterized by DNA double-strand breaks repairing dysfunction and increased sensitivity to ionizing radiation and alkylating reagents. We describe the first successful case of T-cell receptor [TCR]αß/CD19-depleted hematopoietic cell transplantation [HCT] for Artemis deficiency in Japan. A 6-month-old Korean boy was diagnosed with Artemis-deficient severe combined immunodeficiency. He had no human leukocyte antigen (HLA)-matched sibling or unrelated donor. Therefore, TCRαß/CD19-depleted HCT from his haploidentical mother was performed. Despite mixed chimerism in whole blood, T cells achieved complete donor chimerism 6 months after HCT. TCRαß/CD19-depleted HCT could be an effective treatment for patients with radiation-sensitive severe combined immunodeficiency.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Imunodeficiência Combinada Severa , Humanos , Lactente , Masculino , Antígenos CD19 , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Receptores de Antígenos de Linfócitos T alfa-beta , Imunodeficiência Combinada Severa/genética , Linfócitos T , Condicionamento Pré-Transplante , Doadores não Relacionados
6.
J Allergy Clin Immunol ; 149(2): 736-746, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34111452

RESUMO

BACKGROUND: Heterozygous germline mutations in cytotoxic T lymphocyte-associated antigen-4 (CTLA4) impair the immunomodulatory function of regulatory T cells. Affected individuals are prone to life-threatening autoimmune and lymphoproliferative complications. A number of therapeutic options are currently being used with variable effectiveness. OBJECTIVE: Our aim was to characterize the responsiveness of patients with CTLA-4 insufficiency to specific therapies and provide recommendations for the diagnostic workup and therapy at an organ-specific level. METHODS: Clinical features, laboratory findings, and response to treatment were reviewed retrospectively in an international cohort of 173 carriers of CTLA4 mutation. Patients were followed between 2014 and 2020 for a total of 2624 months from diagnosis. Clinical manifestations were grouped on the basis of organ-specific involvement. Medication use and response were recorded and evaluated. RESULTS: Among the 173 CTLA4 mutation carriers, 123 (71%) had been treated for immune complications. Abatacept, rituximab, sirolimus, and corticosteroids ameliorated disease severity, especially in cases of cytopenias and lymphocytic organ infiltration of the gut, lungs, and central nervous system. Immunoglobulin replacement was effective in prevention of infection. Only 4 of 16 patients (25%) with cytopenia who underwent splenectomy had a sustained clinical response. Cure was achieved with stem cell transplantation in 13 of 18 patients (72%). As a result of the aforementioned methods, organ-specific treatment pathways were developed. CONCLUSION: Systemic immunosuppressants and abatacept may provide partial control but require ongoing administration. Allogeneic hematopoietic stem cell transplantation offers a possible cure for patients with CTLA-4 insufficiency.


Assuntos
Antígeno CTLA-4/genética , Mutação em Linhagem Germinativa , Síndromes de Imunodeficiência/terapia , Adolescente , Adulto , Agamaglobulinemia/etiologia , Idoso , Doenças Autoimunes/etiologia , Antígeno CTLA-4/deficiência , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Transplante de Células-Tronco Hematopoéticas , Humanos , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/genética , Lactente , Doenças Pulmonares Intersticiais/etiologia , Masculino , Pessoa de Meia-Idade , Transplante Homólogo , Adulto Jovem
7.
Anal Bioanal Chem ; 414(28): 8125-8142, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36181513

RESUMO

In drug metabolism studies in horses, non-targeted analysis by means of liquid chromatography coupled with high-resolution mass spectrometry with data-dependent acquisition (DDA) has recently become increasingly popular for rapid identification of potential biomarkers in post-administration biological samples. However, the most commonly encountered problem is the presence of highly abundant interfering components that co-elute with the target substances, especially if the concentrations of these substances are relatively low. In this study, we evaluated the possibility of expanding DDA coverage for the identification of drug metabolites by applying intelligently generated exclusion lists (ELs) consisting of a set of chemical backgrounds and endogenous substances. Daprodustat was used as a model compound because of its relatively lower administration dose (100 mg) compared to other hypoxia-inducible factor stabilizers and the high demand in the detection sensitivity of its metabolites at the anticipated lower concentrations. It was found that the entire DDA process could efficiently identify both major and minor metabolites (flagged beyond the pre-set DDA threshold) in a single run after applying the ELs to exclude 67.7-99.0% of the interfering peaks, resulting in a much higher chance of triggering DDA to cover the analytes of interest. This approach successfully identified 21 metabolites of daprodustat and then established the metabolic pathway. It was concluded that the use of this generic intelligent "DDA + EL" approach for non-targeted analysis is a powerful tool for the discovery of unknown metabolites, even in complex plasma and urine matrices in the context of doping control.


Assuntos
Dopagem Esportivo , Animais , Cromatografia Líquida/métodos , Cavalos , Espectrometria de Massas/métodos , Preparações Farmacêuticas , Detecção do Abuso de Substâncias/métodos
8.
J Clin Immunol ; 41(5): 944-957, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33527309

RESUMO

PURPOSE: The purpose of our study was to compare the safety and efficacy of hematopoietic cell transplantation (HCT) using fludarabine (Flu)-based reduced intensity conditioning (RIC) with busulfan (BU) or melphalan (Mel) for primary immunodeficiency diseases (PID). METHODS: We retrospectively analyzed transplant outcome, including engraftment, chimerism, immune reconstitution, and complications in 15 patients with severe combined immunodeficiency (SCID) and 27 patients with non-SCID PID. The patients underwent Flu-based RIC-HCT with BU (FluBU: 7 SCID, 16 non-SCID) or Mel (FluMel: 8 SCID, 11 non-SCID). The targeted low-dose BU with therapeutic drug monitoring was set to 30 mg hour/L for SCID. RESULTS: The 2-year overall survival of all patients was 79.6% and that of patients with SCID in the FluBU and FluMel groups was 100% and 62.5%, respectively. In the FluBU group, all seven patients achieved engraftment, good immune reconstitution, and long-term survival. All five patients receiving umbilical cord blood transplantation achieved complete or high-level mixed chimerism and sufficient specific IgG production. In the FluMel group, six of eight patients achieved complete or high-level mixed chimerism. Viral reactivation or new viral infection occurred in one FluBU group patient and four FluMel group patients. In the non-SCID group, 10 of 11 patients (91%) who received FluMel achieved complete or high-level mixed chimerism but had variable outcomes. Patients with WAS (2/2 patients), NEMO deficiency (2/2 patients), and X-linked hyper IgM syndrome (2/3 patients) who received FluBU achieved complete or high-level mixed chimerism and long-term survival. CONCLUSIONS: RIC-HCT with FluBU is a safe and effective strategy for obtaining high-level donor chimerism, immune reconstitution including B cell function, and long-term survival in patients with SCID. In patients with non-SCID PID, the results varied according to the subtype of the disease. Further prospective studies are required to optimize the conditioning regimen for non-SCID PID.


Assuntos
Bussulfano/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/uso terapêutico , Melfalan/uso terapêutico , Doenças da Imunodeficiência Primária/terapia , Condicionamento Pré-Transplante , Vidarabina/análogos & derivados , Bussulfano/farmacocinética , Pré-Escolar , Combinação de Medicamentos , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Lactente , Contagem de Leucócitos , Masculino , Doenças da Imunodeficiência Primária/imunologia , Doenças da Imunodeficiência Primária/mortalidade , Estudos Retrospectivos , Resultado do Tratamento , Vidarabina/uso terapêutico
9.
Rinsho Ketsueki ; 62(8): 1334-1342, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34497224

RESUMO

Viral infections are one of the leading causes of death in hematopoietic cell transplantation (HCT) and are a problem that should be resolved. For post-HCT viral infections, reduction of antiviral treatment or immunosuppressive drug dose is generally performed; however, the effect of antiviral drug is sometimes limited, and reduction of immunosuppressive treatment might worsen the graft-versus-host disease. Therefore, appropriate infection preventive measures and early diagnosis and therapeutic intervention for viral infections are important. In addition, virus-specific T-cell (VST) therapy is attracting attention as a new treatment method for intractable and refractory post-HCT viral infections. Various methods have been developed to establish VSTs, from a single- to multiple-virus targeting and from related- to third-party-derived donors. Its safety and efficacy have already been reported in clinical trials, and thereby, it is expected to be established as one of the important treatments for post-HCT viral infections.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Viroses , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Linfócitos T , Transplante Homólogo , Viroses/terapia
10.
Transpl Infect Dis ; 22(5): e13331, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32424944

RESUMO

Human herpesvirus-6 (HHV-6) is a common pathogen affecting the human population. Primary HHV-6 infection generally occurs during infancy and causes exanthema subitum. Moreover, HHV-6 may exhibit inherited chromosomally integrated HHV-6 (iciHHV-6) in certain individuals. Although iciHHV-6 is generally known to be nonpathogenic, it may cause reactivation in patients with primary immunodeficiency disease (PID). XIAP deficiency is a rare PID characterized by recurrent hemophagocytic lymphohistiocytosis (HLH). It has been reported that the Epstein-Barr virus primarily causes HLH; however, the other pathogens, including HHV-6, can also cause this complication. We encountered a case of XIAP deficiency accompanied by iciHHV-6. He suffered from recurrent HLH, for which allogeneic bone marrow transplantation (BMT) was performed as a curative therapy. During the course of BMT, the patient experienced HLH three times, but there was no reactivation of endogenous HHV-6 from iciHHV-6. Finally, the patient achieved complete donor chimerism and a decline in HHV-6 DNA copy number in whole blood. This case report demonstrates no evidence of reactivation of iciHHV-6 during BMT in a patient with XIAP deficiency.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 6 , Doenças Genéticas Ligadas ao Cromossomo X , Herpesvirus Humano 4 , Humanos , Transtornos Linfoproliferativos , Masculino , Integração Viral , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X
11.
Rinsho Ketsueki ; 61(8): 870-873, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32908048

RESUMO

A 58-year-old man received high-dose melphalan with autologous peripheral blood stem cell transplantation for multiple myeloma in stringent complete response (sCR). Relapse occurred 4 years after the transplantation, and he was placed on ixazomib, lenalidomide, and dexamethasone (IRd) and achieved sCR. On the 10th day of the 10th course of IRd, he developed fever followed by generalized skin eruption with vesicles, headache, and dizziness. Varicella-zoster virus (VZV) antigen from the vesicle and VZV-DNA from the cerebrospinal fluid were detected, and he was diagnosed with systemic VZV infection. He was placed on intravenous acyclovir (ACV), and the infection resolved completely. VZV infection has been recognized as an important complication associated with the use of proteasome inhibitors; however, to our knowledge, there have been no reported cases of serious systemic VZV infection associated with ixazomib. The clinical course of this case strongly suggests the importance of prophylaxis for VZV infection during treatment with ixazomib.


Assuntos
Compostos de Boro/uso terapêutico , Varicela , Glicina/análogos & derivados , Herpes Zoster , Mieloma Múltiplo , Varicela/complicações , Glicina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia
12.
Mol Phylogenet Evol ; 130: 406-415, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30244151

RESUMO

Endosymbiotic bacteria are known from many metazoan taxa, where they manipulate host biology and reproduction. Here, we used classic PCR amplification and direct DNA sequencing with universal primers for four different endosymbionts to test for their presence in more than 300 specimens of three recent non-marine ostracod superfamilies from different geographic areas and aquatic habitats. We verified these results with "high throughput" amplicon sequencing of 16S of nine selected specimens and evolutionary placement algorithms. The phylogenetic position of endosymbionts detected in ostracod hosts was compared to known endosymbionts from other metazoans. While Wolbachia, Spiroplasma and Rickettsia are absent, we find evidence for the general presence of Cardinium bacteria in natural populations of various non-marine ostracod species. Phylogenetic reconstructions based on Cardinium 16S data and estimates of genetic distances both indicate that Cardinium from ostracods are distantly related to Cardinium from Diptera and Nematoda but represent novel strains with a monophyletic origin. Cardinium bacteria from different ostracod hosts have genetic distances of up to 3.8%, providing evidence against recent and frequent horizontal transmissions amongst the three ostracod superfamilies. High throughput sequencing reveals more than 400 different 16S amplicon sequence variants in the investigated ostracods as well as the presence of different Cardinium strains within individual Eucypris virens and Heterocypris hosts. These results call for future, more in-depth investigations. Mapping Cardinium infections on COI trees of non-marine ostracod hosts shows that the occurrence of these endosymbionts is not linked to genetic species identity or phylogenetic host groups and, except for one ostracod morphospecies, prevalence never reaches 100%.


Assuntos
Organismos Aquáticos/microbiologia , Bacteroidetes/fisiologia , Crustáceos/microbiologia , Animais , Bacteroidetes/genética , Sequência de Bases , Crustáceos/genética , Dípteros/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie , Simbiose
13.
Pediatr Diabetes ; 20(7): 1035-1040, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31322807

RESUMO

Immune dysregulation, polyendocrinopathy, enteropathy, and X-linked (IPEX) syndrome is an autoimmune disorder caused by the dysfunction of FOXP3, which leads to regulatory T-(Treg) cell dysfunction and subsequently autoimmunity including type 1 diabetes mellitus (T1D). Presently, allogeneic hematopoietic stem cell transplantation (HSCT) is a potential curative therapy for IPEX syndrome, but not for T1D. Generally, after complete loss of pancreatic ß-cells, HSCT cannot improve the prognosis of T1D. Here, we report the case of a 16-year-old adolescent with late-onset of FOXP3 R347H mutation associated IPEX syndrome with T1D, where insulin dependency was ameliorated following HSCT. This patient with insulin-dependent diabetes mellitus required insulin dosage of 1.28 U/kg/day for 1 month before HSCT. Although the results of glucose homeostasis before HSCT revealed impaired insulin secretion and low ΔC-peptide immunoreactivity (CPR, 1.0 ng/mL), the patient withdrew insulin infusion and remained euglycemic at 15 months after HSCT, and had normal ß-cell function with improved ΔCPR (3.4 ng/mL) at 20 months after HSCT. The present case suggests that HSCT for T1D-associated IPEX syndrome improves Treg deficiency and prevents elimination of ß-cells. We speculate that the period from the onset of T1D to HSCT could affect the therapeutic efficacy for T1D with IPEX, and early intervention with HSCT before or immediately after the onset of DM can rescue ß-cells and remit T1D completely. Our study elaborates not only the therapeutic strategy for T1D with IPEX, but also the pathogenic mechanism in general T1D.


Assuntos
Diabetes Mellitus Tipo 1/congênito , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/terapia , Diarreia/complicações , Doenças Genéticas Ligadas ao Cromossomo X/complicações , Transplante de Células-Tronco Hematopoéticas , Doenças do Sistema Imunitário/congênito , Insulina/deficiência , Adolescente , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Diarreia/genética , Diarreia/terapia , Fatores de Transcrição Forkhead/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Humanos , Doenças do Sistema Imunitário/complicações , Doenças do Sistema Imunitário/genética , Doenças do Sistema Imunitário/terapia , Insulina/metabolismo , Masculino , Mutação , Indução de Remissão , Resultado do Tratamento
20.
Cell Tissue Res ; 366(2): 483-497, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27449928

RESUMO

Spermatozoa of the ostracod superfamily Cypridoidea include some of the longest in the animal kingdom, but unlike other so-called giant spermatozoa, they are aflagellate, probably evolved only once, and represent an exceptionally old trait. Sperm length variations within cypridoidean species remain poorly known, a lack that hinders the development of hypotheses to explain their length and variation. For this study, the lengths of 500 spermatozoa from each of five species of freshwater cypridoidean ostracods, Candonopsis tenuis (Brady, 1886), Fabaeformiscandona subacuta (Yang, 1982), Heterocypris rotundata (Bronshtein, 1928), Ilyocypris japonica Okubo, 1990, and Notodromas trulla Smith and Kamiya, 2014, were measured, including the lengths of the posterior and anterior regions. No overall pattern in sperm variation was discernible. Length variations between species, between males of the same species, and within individual males varied from low (Candonopsis tenuis) to extraordinarily large (Notodromas trulla and Fabaeformiscandona subacuta). Sperm competition, cryptic female choice, sperm heteromorphism, and testis size are unlikely to explain all of the variations observed. Age structures of the populations sampled might play a role in explaining some intraspecific variation. The differing amounts of variation in sperm characters revealed in this study suggest that multiple evolutionary trends and pressures shape sperm lengths in this superfamily.


Assuntos
Crustáceos/metabolismo , Espermatozoides/citologia , Animais , Masculino , Mudanças Depois da Morte , Especificidade da Espécie
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