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The evolution of the diagnosis and understanding of primitive and embryonic neoplasms in children: living through an epoch.

Approximately 30% of malignant neoplasms in children are dysontogenetic tumors whose pathologic features resemble or recapitulate those of the developing organ or tissue of origin. Archetypes include classic neuroblastoma, Wilms' tumor, and embryonal rhabdomyosarcoma. This review traces the history of the principal types of dysontogenetic neoplasms and the primitive round cell tumors, Ewing's sarcoma, and peripheral primitive neuroectodermal tumor. Retinoblastoma, neuroblastoma, and Wilms' tumor were first described in the 19th century but with several different appellations than those we use today. Although some progress was made in the surgical management of Wilms' tumor during the 1940s and 1950s, most of these unique solid neoplasms of childhood were seen as essentially untreatable and inevitably fatal; surgery and perhaps irradiation were the principal therapeutic offerings. The folic acid analogue, aminopterin, was reported in 1948 as inducing the first complete but temporary remission in acute childhood leukemia. The chemotherapeutic era began shortly thereafter with effective chemotherapy in the management of Wilms' tumor with the introduction of dactinomycin. Pathologists were no longer restricted to being purveyors of the death sentence; they were now responsible for differentiating one type of primitive and embryonic neoplasm from another by using a variety of ancillary techniques, including tissue culture, electron microscopy, immunohistochemistry, and cytogenetics. Favorable or unfavorable morphologic types and subtypes of tumors were defined and, together with the pathologic staging, became incorporated into the therapeutic plan and prognostic assessment. During the past 40 years, these tumors progressed from being virtually treatment resistant to having an overall 5-year survival of 70% or greater. Through the cooperative efforts of pediatric hematologists/oncologists, pediatric surgeons, radiation therapists, and pathologists, the primitive and embryonic neoplasms of childhood are now viewed as some of the most treatable and curable of cancers.

Child↗

Comparison of microscopic examination and human papilloma virus dna subtyping in vulvar lesions of premenarchal girls

Background: In premenarchal children the diagnosis of vulvar condyloma is often based on the clinical or microscopic appearance of the lesions. Other techniques for diagnosing condyloma such as DNA subtyping are not always used by providers. The purpose of this study is to compare the microscopic examination and Human Papilloma Virus (HPV) DNA subtyping of vulvar specimens from premenarchal girls to determine whether DNA subtyping aids in the diagnosis process.Methods: Eleven premenarchal girls were taken to the operating room for the treatment of clinically diagnosed condyloma between 1993 and 1999 at the University of Michigan Medical Center. In all patients, tissue was sent for pathologic evaluation and in 10 patients the specimens also underwent DNA subtyping. One patient had prior DNA subtyping. All the other lesions were surgically ablated. Results: The average age of our patients at the time of surgery was 2.3 years, range 1-6 years. Four patients had prior surgical treatment and two patients had undergone prior medical treatment. The microscopic diagnosis was condyloma in 8 patients, squamous papilloma with focal koilocytosis not totally diagnostic for condyloma in 1 patient, chronic inflammatory infiltrate in 1 patient, and 1 patient had papillary squamous hyperplasia with no koilocytosis.All 11 specimens tested positive for HPV DNA, 10 specimens contained at least one of the low risk subtypes (6, 11, 42, 43, 44) and 1 tests positive for low risk as well as high risk HPV type (16, 18, 31, 33, 35, 45, 51, 52, 56).Conclusion: Although all our patients with a clinical diagnosis of condyloma tested positive for HPV DNA, only 8 of 11 were definitely diagnosed with condyloma by microscopic examination. We therefore suggest that in premenarchal patients with verrucous lesions in the anogenital area HPV DNA subtyping be considered to avoid confusion with the diagnosis.

Journal Article↗

Fatal familial insomnia and familial Creutzfeldt-Jakob disease: disease phenotype determined by a DNA polymorphism.

Fatal familial insomnia (FFI) and a subtype of familial Creutzfeldt-Jakob disease (CJD), two clinically and pathologically distinct diseases, are linked to the same mutation at codon 178 (Asn178) of the prion protein gene. The possibility that a second genetic component modified the phenotypic expression of the Asn178 mutation was investigated. FFI and the familial CJD subtype segregated with different genotypes determined by the Asn178 mutation and the methionine-valine polymorphism at codon 129. The Met129, Asn178 allele segregated with FFI in all 15 affected members of five kindreds whereas the Val129, Asn178 allele segregated with the familial CJD subtype in all 15 affected members of six kindreds. Thus, two distinct disease phenotypes linked to a single pathogenic mutation can be determined by a common polymorphism.

Adult↗

Subtypes of renal cell carcinoma. Different onset and sites of metastatic disease.

Different subtypes of renal cell carcinoma have different genetic features and prognoses. Whether the patterns of metastatic spread of different subtypes of renal cell carcinoma are different is unknown. To assess this, we reviewed the time course and sites of all pathologically confirmed metastatic disease in patients who underwent resection of the primary tumor at Brigham and Women's Hospital, Boston, MA, between 1973 and 1997. In 82 patients, 119 metastatic lesions were identified. Compared with clear cell tumors, papillary tumors were more likely to be Fuhrman grade 3 or 4, to have metastases present at the time of resection, and to involve lymph nodes but not lung. Metastases associated with chromophobe tumors developed in 3 patients, all of whom had Fuhrman grade 2 tumors, and were found only in the liver. We conclude that different subtypes of renal cell carcinoma develop pathologically confirmed metastases at different times and sites. The value of Fuhrman grading may depend on the subtype of renal cell carcinoma.

Aged↗

Decreased levels of the brain specific 24S-hydroxycholesterol and cholesterol precursors in serum of multiple sclerosis patients.

The serum concentration of 24S-hydroxycholesterol reflecting brain cholesterol turnover may be a possible marker for neurodegeneration and demyelination in multiple sclerosis. Serum was analyzed for cholesterol precursors and oxysterols in multiple sclerosis patients of different clinical subtypes (n=20 each subtype) and in 37 healthy controls. Serum 24S-hydroxycholesterol levels were lower in primary progressive and in older relapsing remitting multiple sclerosis patients. Furthermore, serum levels of lathosterol were decreased in all clinical subtypes. The results are important given recent interest in statin treatment in multiple sclerosis, which will further decrease the cholesterol precursor and oxysterol levels. The decreased levels of brain specific and peripheral sterols indicate a role for cholesterol homeostasis in relation to the pathology of multiple sclerosis, at least in the primary progressive clinical subtype.

Adult↗

Cytologic and histologic correlation of atypical glandular cells of undetermined significance.

To determine the cytologic and histologic correlation of atypical glandular cells of undetermined significance (AGUS) in Papanicolaou smears, a cytology file from January 1998 to May 1999 was reviewed. Surgical pathology files were searched to determine which patients received subsequent biopsies. One hundred thirty-two patients with AGUS were identified. Corresponding biopsies were available for 82 of these cases. AGUS has been sub-classified into 3 subtypes: 1) AGUS, favor reactive; 2) AGUS, not otherwise specified; and 3) AGUS, favor neoplasia. The pathologic findings for the respective Papanicolaou smears with the diagnosis of each subtype of AGUS through the follow-up period were as follows: benign lesions in 56.1%, 0%, and 1.2%; squamous intraepithelial lesions 2.4%, 0%, and 1.2%; glandular intraepithelial lesions 0%, 0%, and 17.1%; endometrial simple hyperplasia 1.2%, 0%, and 0%; and carcinoma 0%, 9.8%, and 11%, respectively. In conclusion, AGUS, on cervical cytologic screening, was correlated with significant pathologic findings in 41.5% of the patients (37.8% with preinvasive or invasive glandular lesions and 9.6% with combined squamous intraepithelial lesions). It is thought that intensive follow-up studies, including colposcopy, cervical biopsy, and curettage, should be recommended for complete evaluation of AGUS.

Adenocarcinoma↗

Prostaglandin E receptor subtypes in cultured rat microglia and their role in reducing lipopolysaccharide-induced interleukin-1beta production.

Prostaglandins (PGs) are potent modulators of brain function under normal and pathological conditions. The diverse effects of PGs are due to the various actions of specific receptor subtypes for these prostanoids. Recent work has shown that PGE2, while generally considered a proinflammatory molecule, reduces microglial activation and thus has an antiinflammatory effect on these cells. To gain further insight to the mechanisms by which PGE2 influences the activation of microglia, we investigated PGE receptor subtype, i.e., EP1, EP2, EP3, and EP4, expression and function in cultured rat microglia. RT-PCR showed the presence of the EP1 and EP2 but not EP3 and EP4 receptor subtypes. Sequencing confirmed their identity with previously published receptor subtypes. PGE2 and the EP1 agonist 17-phenyl trinor PGE2 but not the EP3 agonist sulprostone elicited reversible intracellular [Ca2+] increases in microglia as measured by fura-2. PGE2 and the EP2/EP4-specific agonists 11-deoxy-PGE1 and 19-hydroxy-PGE2 but not the EP4-selective agonist 1-hydroxy-PGE1 induced dose-dependent production of cyclic AMP (cAMP). Interleukin (IL)-1beta production, a marker of activated microglia, was also measured following lipopolysaccharide exposure in the presence or absence of the receptor subtype agonists. PGE2 and the EP2 agonists reduced IL-1beta production. IL-1beta production was unchanged by EP1, EP3, and EP4 agonists. The adenylyl cyclase activator forskolin and the cAMP analogue dibutyryl cAMP also reduced IL-1beta production. Thus, the inhibitory effects of PGE2 on microglia are mediated by the EP2 receptor subtype, and the signaling mechanism of this effect is likely via cAMP. These results show that the effects of PGE2 on microglia are receptor subtype-specific. Furthermore, they suggest that specific and selective manipulation of the effects of PGs on microglia and, as a result, brain function may be possible.

Adenylyl Cyclases↗

Warthin's tumor of parotid gland on Tc-99m pertechnetate scintigraphy with lemon juice stimulation: Tc-99m uptake, size, and pathologic correlation.

The aim of this study was to evaluate the usefulness of technetium-99m (Tc-99m) pertechnetate scintigraphy with lemon juice stimulation in the diagnosis of Warthin's tumor and its correlation with Tc-99m uptake, tumor size, and histologic subtype. Tc-99m pertechnetate scintigraphy before and after lemon juice stimulation and pathologic specimens of 34 Warthin's tumors and 47 non-Warthin's lesions were retrospectively evaluated. Tc-99m uptake of Warthin's tumors before and after stimulation was visually graded as follows: absent; indeterminate; low grade; definite; and strong. Tumor size was defined as maximum diameter of the tumor measured from the surgical specimen. Warthin's tumors were classified into three histologic subtypes according to the ratio of epithelial and lymphoid stromal components: predominant epithelial; intermediate; and low-grade epithelial types. Eighteen of 34 (53%) Warthin's tumors and one benign lymphoepithelial cyst showed higher uptake than that of the normal parotid gland on Tc-99m scintigraphy before lemon juice stimulation. Thirty-two of the 34 (94%) Warthin's tumors, one benign lymphoepithelial cyst, one pleomorphic adenoma, and one oncocytoma revealed higher uptake than that of the normal parotid gland on Tc-99m scintigraphy after lemon juice stimulation. The mean size was 37 mm in strong uptake Warthin's tumors, 24 mm in definite uptake tumors, 19 mm in low-grade uptake tumors, and 12 mm in low-grade uptake tumors excluding those tumors with large cystic component. There was a significant correlation between tumor size and degree of Tc-99m uptake after lemon juice stimulation. However, there was no correlation between histologic subtype and Tc-99m uptake, and histologic subtype and tumor size in Warthin's tumors. Our study concludes that Tc-99m pertechnetate scintigraphy with lemon juice stimulation is useful for the detection and diagnosis of Warthin's tumor. The degree of uptake in Warthin's tumor on Tc-99m scintigraphy with lemon juice stimulation depends mainly on tumor size and the presence of large cystic component in it.

Adenolymphoma↗

A case of unilateral adrenal hyperplasia: the diagnostic dilemma of hyperaldosteronism.

OBJECTIVE: To report the successful laparoscopic surgical management of a case of right unilateral adrenal hyperplasia. METHODS: We present a case of unilateral adrenal hyperplasia and review the pertinent literature. The effectiveness of surgical treatment of unilateral adrenal hyperplasia is evaluated. RESULTS: A 50-year-old man had a 7-year history of hypertension, which had been treated with antihypertensive medications. On initial assessment, he was taking long-acting diltiazem, 240 mg twice a day, and his blood pressure was 150/84 mm Hg. He was noted to have recurrent hypokalemia, low plasma renin activity, increased plasma aldosterone concentration, and high urinary aldosterone levels. Magnetic resonance imaging of the adrenal glands revealed a normal left adrenal gland and fullness of the right adrenal gland. Selective adrenal vein catheterization showed findings consistent with a right-sided adrenal gradient. Surgical removal of the right adrenal gland laparoscopically alleviated his symptoms and cured his hypertension and hypokalemia. Pathologic examination of the right adrenal gland revealed diffuse hyperplasia of the zona fasciculata and zona reticularis. Plasma aldosterone, renin, and potassium levels returned to normal postoperatively, and his blood pressure declined to 120/70 mm Hg. At 1-year follow-up, the patient remained normotensive without the need for antihypertensive agents. CONCLUSIONS: This rare type of hyperaldosteronism, known as unilateral adrenal hyperplasia, is difficult to categorize not only because it fails to typify a conventional subtype but also because it is difficult to confirm the pathologic diagnosis. Recognition of the variety of provocative, biochemical, and imaging results that may be seen in this disorder is important in making the correct diagnosis. Determining unilaterality of disease by selective adrenal vein sampling can result in a cure of hypertension and hypokalemia by surgical resection.

Adrenal Glands↗

Mechanisms of disease: focal segmental glomerulosclerosis.

Focal segmental glomerulosclerosis (FSGS), a subtype of "idiopathic nephrotic syndrome", is not a single disease, but a lesion that initially affects the glomerulus followed by the tubulointerstitium and renal vessels. The term 'FSGS' does not accurately encompass the various pathologic features of the glomerulus, which are not always focal, segmental or sclerotic. Particular variants of FSGS, such as collapsing glomerulopathy and the glomerular tip lesion, exemplify the nosologic uncertainty inherent in the classification of glomerular lesions. Pathologic variation notwithstanding, all pathologic processes that affect the podocyte lead to one of the histologic subtypes of FSGS. This specialized cell type has essential roles in maintaining the integrity of glomerular architecture, resisting endocapillary hydraulic pressure and hindering egress of proteins into the urinary space. Once initiated, podocyte lesions and ensuing fibrosis are usually irreversible, at least in human forms of FSGS. Remarkable progress has been made in unraveling the mechanisms of podocyte dysregulation that accompany the cellular variants of FSGS and in identifying genetic mutations affecting proteins of the slit diaphragm. Hopefully, this progress will drastically improve treatments for what is one of the most difficult therapeutic challenges to confront the nephrologist.

Animals↗

Renal cell carcinomas in children and young adults: increased incidence of papillary architecture and unique subtypes.

Renal cell carcinomas in children and young adults are rare, and the pathologic features of these tumors have not been well described. We reviewed 24 renal cell carcinomas in children and young adults ages 6 to 29 years, 14 of whom were younger than 18 years of age. Fourteen were female. In 19 (79%) of 24 cases, the tumor met histologic criteria for papillary renal cell carcinoma, with at least 50% papillary architecture. Four of the remaining five cases were typical clear cell tumors in patients known to have von Hippel Lindau syndrome, and one case was of chromophobe type. In the papillary tumors, calcifications, high nuclear grade, extracapsular extension (American Joint Commission on Cancer stage T3), and lymph node metastases were common. Among these papillary tumors, four distinct histologic patterns could be identified. Collecting duct-like tumors (two cases) involved the large collecting ducts, were multifocal and predominantly papillary, and had focal tubular and solid areas. These tumors were reactive for epithelial membrane antigen (EMA) and keratins, including CK7, but negative for Ulex europeaus and high molecular weight keratin 34BE12. Voluminous cell tumors (four cases) were composed of cells with extremely voluminous clear cytoplasm and, although predominantly papillary, had areas that also resembled clear cell tumors. These tumors were reactive for keratins AE1/AE3 but were otherwise negative for all other keratins, EMA, and U. europeaus. One of these tumors showed an X;7 translocation. Adult type tumors (12 cases) resembled papillary tumors of adults. These tumors were reactive for EMA and keratins, including CK7, and all but one were negative for U. europeaus and keratin 34BE12. This last case had trisomies of chromosomes 7, 16, 17, and 20. The final neuroendocrinelike case was multifocal, organoid, and composed of nests of small cells in a neuroendocrinelike pattern. Three of 13 patients were alive with disease at last follow-up, and three additional patients died of disease, all within 2 years. Progression was highly associated with lymph node involvement at the time of resection. We conclude that the clinicopathologic features of renal cell carcinomas in children and young adults differ from those arising in older adults. These tumors are characteristically high-grade, high-stage, papillary tumors with numerous calcifications, and several subtypes can be identified based on histologic, immunohistochemical, and cytogenetic features. Some subtypes appear to be unique to this age group.

Adolescent↗

Clinicopathologic characteristics of sporadic Japanese Creutzfeldt-Jakob disease classified according to prion protein gene polymorphism and prion protein type.

We analyzed neuropathologic features of 23 Japanese patients with sporadic Creutzfeldt-Jakob disease (sCJD) by means of prion protein (PrP) immunolabeling associated with codon 129 polymorphism of the PrP gene and western blot analysis of protease-resistant PrP (PrP type). Clinical features, particularly age at onset, disease duration, periodic synchronous discharge and presence of myoclonus, were also analyzed. This study included 11 cases of subacute spongiform encephalopathy (SSE), 10 cases of panencephalopathic (PE)-type sCJD and two cases of thalamic-type sCJD, classified according to cerebral pathology findings. According to PrP gene polymorphism and PrP type, 18 cases were classified as MM1-type, two as MV1-type, two as MM2-type and one as MM1 + 2-type sCJD. SSE and PE-type sCJD showed similar clinical features, with the exception of disease duration, codon 129 polymorphism and PrP type. Thalamic-type sCJD showed different clinical features and PrP type. We suggest that SSE and PE-type sCJD comprise the sCJD subtype and that PE-type sCJD is a prolonged pathologic phenotype of SSE. When we compare our results with those from a series of Caucasian sCJD patients, the percentages of codon 129 polymorphisms differed, as did classification based on PrP gene polymorphism and PrP type; our series included many PE-type sCJD cases and disease duration was relatively long and MM2-type cases showed clinicopathologic variability.

Adult↗

Clinico-pathological study of Hodgkin's lymphoma in a cancer center in Taiwan.

The incidence rate of Hodgkin's lymphoma (HL) in Asia is much lower than that of western countries. This study demonstrates the incidence rate and the clinico-pathological features of HL in a cancer center in Taiwan with respect to demographics, histological subtypes and clinical outcomes. We evaluated the clinical, morphological and immunohistochemical features of 42 patients with HL during the period of 1995-2002. Clinico-pathological features and follow-up were scrutinized. There were 21 males and 21 females. The incidence rate of HL in malignant lymphoma in our center was 7%. The median age was 26 years old. There was no apparent bimodal age distribution. The most prevalent histological subtype was nodular sclerosis (69%). Mixed cellularity, lymphocyte rich, lymphocyte depletion, nodular lymphocyte predominance and unclassified was 4.8%, 4.8%, 0%, 7% and 14% respectively. The most common site at presentation was the cervical lymph node (31 cases; 74%). Clinically, 1 (2%) had stage I disease, 23 (55%) stage II, 8 (19%) stage III and 10 (24%) stage IV. Two cases had rare primary bone marrow HL of stage IV. Both cases died within 1 month. Clinical stage (P=0.09) and age (P<0.001) were prognostic parameters determining the overall survival.

Adolescent↗

Apolipoprotein E polymorphism in cerebrovascular disease.

OBJECTIVES: The aim of this study was to investigate the relationship between the apo E genotype with acute cerebral infarction and primary intracerebral haemorrhage and to examine the relationship of the apo E genotype with mortality following acute stroke. MATERIALS AND METHODS: We studied 592 cases of acute stroke and 289 healthy control subjects clinically free of cerebrovascular disease. Pathological type of stroke was determined by cranial computed tomography and the subtype of cerebral infarction classified according to the Oxfordshire Community Stroke Project Classification (OCSP). Apo E genotype was determined using polymerase chain reaction. RESULTS: There was no difference in apo E genotype frequency between cases and controls (chi2 = 3.58, 5 d.f., P = 0.60). Apo E genotypes were not related to the pathological type of stroke (cerebral infarction, CI, n = 532 and primary intracranial haemorrhage, PICH, n = 60, (chi2 =3.738, 4 d.f., P=0.44) nor with the Oxfordshire Community Stroke Project Classification subtypes of cerebral infarction, lacunar infarction, LACI (n = 169), total anterior circulation infarction, TACI (n = 117), partial anterior circulation infarction, PACI (n = 173), posterior circulation infarction, POCS (n = 54) and including those cerebral infarcts which could not be classified (n= 19), chi2 =31.1, 20 d.f., P=0.153). At the time of the analysis, 243 cases (41.0%) had died. The median follow-up (including death) was 851 days. There was no relationship between time to death and apo E genotype in cases of either CI or PICH. CONCLUSION: In this population, there was no relationship between the apolipoprotein E polymorphism and the pathogenesis of cerebral infarction or primary intracerebral haemorrhage. Apo E genotype was not related to all-cause mortality following stroke.

Aged↗

Remodeling of the airway epithelium in asthma.

Several pathologic changes occur in the airway epithelium in asthma, but the relationship between these changes and the initiation and progression of asthma remains poorly understood. One possibility is that changes in the structure and function of the epithelium induced by environmental exposure in genetically susceptible subjects represent primary pivotal events that occur early in the pathogenesis of asthma. Alternatively, these epithelial changes may occur simply as a consequence of pivotal early events in other systems, such as immune deviation in childhood to a helper T cell type 2 (Th2) subtype of CD4(+) cells. Epithelial desquamation in asthma represents a pathologic change that is frequently cited as important for the mechanisms of airway remodeling and airway hyperresponsiveness. Desquamation of the epithelium may not represent true pathology, however, but may instead be an artifact of tissue sampling and handling. Evidence is more firm for other pathologic changes in the epithelium. For example, goblet cell numbers are increased in asthma, leading to increases in stored mucins in the epithelium and in secreted mucins in sputum. The functional consequences of these changes include sputum production and airway narrowing, which lead to asthma exacerbations. Currently available data suggest that an important mechanism for goblet cell hyperplasia in asthma is the action of Th2 cytokines. Improved understanding of epithelial goblet cell abnormalities in asthma will hopefully lead to novel therapies for mucin hypersecretion, which is an important cause of morbidity and mortality.

Animals↗

Ullrich's congenital atonic sclerotic muscular dystrophy. A case report.

A 5-year old girl with Ullrich's atonic-sclerotic muscular dystrophy is reported and 16 previously reported cases are reviewed. The clinical features, in particular proximal contractures, distal hyperextensibility, mild dysmorphism and hyperhidrosis, allow recognition of this subtype of congenital muscular dystrophy, which has no specific pathological characteristics. There is evidence in favour of an autosomal recessive mode of inheritance.

Child, Preschool↗

Congenital atlanto-axial dislocation.

Report about 105 personally operated cases of congenital atlanto-axial dislocation. This fairly common malformation in India occurs three times more in males than in females, 50% show symptoms before the age of 20 years, the other half during the third decade of life. Transient attacks of cervical cord compression occur with progressive motor and posterior column defect, and sometimes unconsciousness and cerebellar involvement are characteristic. The diagnosis is proved by X-rays including tomograms and dynamic studies. Three types of malformation can be differentiated: Group I with assimilation of the atlas, group II with anomalies of the odontoid process and group III with a normal atlas and axis. The different types and subtypes are described in detail as well as the pathological and pathogenic factors. The treatment and personal experiences show that the early treatment with posterior decompression, sometimes combined with posterior fusion was unsuccessful and resulted in a high mortality and morbidity. The antero-lateral approach, described by the author proved to be the method choice. The prognosis is dependent on the extent of the damage to the cord before treatment. Early diagnosis and treatment lead to excellent results.

Adolescent↗

Muscle pathology of myotonia congenita.

We have investigated the muscle biopsies of 8 patients with myotonia congenita. There were 2 families with autosomal recessive inheritance (5 cases), 1 with autosomal dominant inheritance, and 2 sporadic cases. Mild abnormalities were seen with routine pathological preparations which were nondiagnostic. Histochemical studies of fiber subtypes demonstrated a complete absence of Type 2B muscle fibers in all of our patients regardless of the type of inheritance. this is the first reporot of an entity in which there is a consistent absence of a muscle fiber type, and some speculation has been made as to the possible causes.

Adenosine Triphosphatases↗