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PubMed2004

Rapid inactivation of vaccinia virus in suspension and dried on surfaces.

A bioterrorist attack with smallpox virus would be disastrous with a 30% disease fatality rate. Such an outbreak would require biomedical laboratories for diagnosis and analyses and extensive use of clinical care facilities for patient quarantine. Safe decontamination procedures will have to be in place in order to limit the spread of the disease. In order to fulfil this need, Sanytex, a new non-corrosive commercial solution containing quaternary ammonium, aldehydes, alcohol and detergent, was tested with a view to using it in decontamination procedures. Vaccinia virus was used in this investigation as a model for smallpox virus. We determined exposure time and the concentration of Sanytex required to inactivate the virus in suspension and dried on surfaces in the presence of protein (up to 70 mg/mL). After 3 min incubation, Sanytex at a concentration of 3% led to a complete inactivation (virus titre reduction >10(4)-fold of vaccinia virus in suspension containing protein up to 30 mg/mL. A virus suspension containing 70 mg protein/mL, simulating biological fluids, was decontaminated with 10% Sanytex after 3 min. After 10 min, Sanytex at a concentration of 30%, applied on to a dried vaccinia virus contaminated surface in the presence of protein (10 mg/mL before desiccation), led to complete decontamination of the surface. Thirty minutes exposure with 30% Sanytex was necessary for a virus titre reduction of >10(4)-fold on a surface contaminated with a dried suspension of vaccinia virus in the presence of protein at 70 mg/mL. Sanytex is not corrosive, not toxic to environment and stable for up to three months even diluted. Its virucidal effect was preserved when used under pressure in a fire-hose nozzle. These results support the use of Sanytex for decontamination of biological fluids and surfaces contaminated by the smallpox virus.

Alcohols↗
PubMed2005

The tail suspension test as a model for assessing antidepressant activity: review of pharmacological and genetic studies in mice.

Since its introduction almost 20 years ago, the tail suspension test has become one of the most widely used models for assessing antidepressant-like activity in mice. The test is based on the fact that animals subjected to the short-term, inescapable stress of being suspended by their tail, will develop an immobile posture. Various antidepressant medications reverse the immobility and promote the occurrence of escape-related behaviour. This review focuses on the utility this test as part of a research program aimed at understanding the mechanism of action of antidepressants. We discuss the inherent difficulties in modeling depression in rodents. We describe how the tail suspension differs from the closely related forced swim test. Further, we address some key issues associated with using the TST as a model of antidepressant action. We discuss issues regarding whether it satisfies criteria to be a valid model for assessing depression-related behavioural traits. We elaborate on the tests' ease of use, strain differences observed in the test and gender effects in the test. We focus on the utility of the test for genetic analysis. Furthermore, we discuss the concept of whether immobility maybe a behavioural trait relevant to depression. All of the available pharmacological data using the test in genetically modified mice is collated. Special attention is given to selective breeding programs such as the Rouen 'depressed' mice which have been bred for high and low immobility in the tail suspension test. We provide an extensive pooling of the pharmacological studies published to date using the test. Finally, we provide novel pharmacological validation of an automated system (Bioseb) for assessing immobility. Taken together, we conclude that the tail suspension test is a useful test for assessing the behavioural effects of antidepressant compounds and other pharmacological and genetic manipulations relevant to depression.

Analysis of Variance↗
PubMed2004

Macrophage suspensions prepared from a blood unit for treatment of refractory human ulcers.

This paper presents an innovative method for the treatment of refractory wounds, starting with a blood unit, that is based on a biological approach. Local wound repair is one of the major unresolved clinical problems. Age, infection, clinical conditions such as diabetes mellitus, cardiac, renal, lung and liver failure, malnutrition and immunological deficiencies are among the reasons for wound repair delay or failure. Many chronic ulcers resist conventional treatment and do not heal for months and years, thus causing substantial morbidity and even mortality. The method for macrophage suspension treatment consists of introducing into the wound live cells that play a major role in the process of wound healing. The suspension is prepared from a blood unit of a healthy donor in a cost-effective, closed, sterile system. In the process of preparation, the macrophages are activated by hypo-osmotic shock to enhance their various functions in wound repair. The cells are applied to the wound either by local injection or by direct deposition into the wound. In most cases (90%), only one treatment is sufficient. Since 1995, macrophage suspensions have been used successfully in more than 1000 patients in several hospitals in Israel, without any side effects. Our results show that the use of a macrophage suspension is a safe and effective therapeutic strategy that shortens the healing period, reduces risk of complications and morbidity and improves the quality of life for long-suffering patients. This treatment requires no hospitalization and can be given on an ambulatory basis.

Adolescent↗
PubMed1999

Influence of thrombin in suspension, surface activation, and high shear on platelet surface GPIb/IX distribution.

Studies in our laboratory have shown that glycoprotein Ib/IX (GPIb/IX), the receptor for von Willebrand factor (vWf), is not decreased in number or cleared from exposed surfaces to the internal membranes of platelets activated in suspension by thrombin alone, by interaction with formvar surfaces alone, or by a combination of the two modes of stimulation. The present study has examined the influence of three different types of stimulation including activation by thrombin in suspension followed by surface activation on formvar, then exposure to high shear stress in a flat chamber. Samples were fixed for study in the electron microscope after each single stimulus, after the combination of two modes of activation, and after the combination of suspension, surface, and shear activation and were stained by an immunogold procedure using monoclonal antibodies to localize GPIb/IX on singly, doubly, or multiply activated cells. The results demonstrate that GPIb/IX receptors remain on activated platelets from edge to edge and that there is no difference in the number or distribution of receptor complexes on thrombin-activated platelets, surface-activated cells, or platelets exposed to the combination of suspension, surface, and shear activation. The findings add additional support to the concept that GPIb/IX is not a mobile receptor and is not cleared from exposed surfaces to internal membranes under physiologic conditions.

Blood Platelets↗
PubMed1999

The pharmacokinetics of ibuprofen suspension, chewable tablets, and tablets in children with cystic fibrosis.

OBJECTIVES: The objectives of this study were to compare the pharmacokinetic parameters of ibuprofen administered as a suspension, chewable tablet, or tablet in children with cystic fibrosis and to determine the optimal blood sampling times for measuring ibuprofen peak concentrations. STUDY DESIGN: A single oral 20 mg/kg dose of ibuprofen was administered, and blood samples were obtained at 15, 30, 45, 60, 120, 240, and 360 minutes after the dose was administered. Peak plasma concentration (Cmax ), time to peak concentration (Tmax ), and other pharmacokinetic parameters were determined and compared (analysis of variance and analysis of covariance). RESULTS: Thirty-eight children were included (22, 4, and 12 in the suspension, chewable tablet, and tablet groups, respectively). Tmax was the only parameter for which statistical differences were noted (suspension vs tablet, P </=.02). After age and sex were removed as potential confounding variables, Tmax remained statistically different (P </=.001). CONCLUSIONS: A 20 mg/kg dose of ibuprofen suspension is recommended, with blood samples for pharmacokinetic analysis obtained 30, 45, and 60 minutes after the dose is administered. Obtaining the first blood sample 1 hour after dose administration will miss approximately 90% of peak concentrations, increasing the likelihood of overdosing.

Administration, Oral↗
PubMed2000

Charcoal suspension for tumor labelling modifies macrophage activity in mice.

We have previously developed a charcoal suspension for injection into human breast cancers in order to facilitate their location during surgery. We observed that charcoal particles were ingested by intra and peritumoral macrophages, some of which carried the particles at some distance from the injection site. We studied the influence of the formulation parameters of the charcoal suspension for intratumoral injection on in vitro and in vivo activation and in vivo mobilization of mouse peritoneal macrophages after intra-peritoneal injection of 2 mL of each preparation. The influence of the charcoal origin (peat vs wood), granulometry, suspension vehicle (water for parenteral injection, vs saline), concentration and excipients were studied. Micronized peat charcoal in water for injection at the highest studied concentration reduced macrophage activation in vitro and in vivo. However, macrophage mobilization was weaker than after thioglycolate injection and did not seem to be charcoal dose-dependent. The additives incorporated in the charcoal suspension led in vivo to increased peritoneal macrophage activation and mobilization (mannitol, and glucose), only increased activation (polysorbate 80 and pluronic F68) or mobilization (dextran 40, egg lecithin, and cabosil), or inhibited both activation and mobilization (cremophor EL).

Animals↗
PubMedDate not supplied

Comparative bioavailability of ceftibuten in capsule and suspension forms.

The comparative bioavailability of ceftibuten, a new third-generation cephalosporin antibiotic given orally once daily, in capsule and suspension dosage forms, was assessed in healthy male subjects. In three separate studies, subjects received either a 400-mg dose as a suspension or one laboratory-batch, 400-mg capsule; one laboratory-batch, 400-mg capsule or two laboratory-batch, 200-mg capsules; or one production-batch, 400-mg capsule or two laboratory-batch, 200-mg capsules. Plasma samples were assayed for ceftibuten using high-performance liquid chromatography, and the data were assessed using pharmacokinetic and statistical methods. Confidence intervals for the maximum plasma concentration and the area under the plasma concentration-time curve extrapolated to infinity were within 80% to 125% of guidelines, demonstrating the bioequivalence of the two treatments within each of the three studies. One 400-mg capsule (laboratory or production batch) was bioequivalent to two 200-mg capsules used in a clinical efficacy trial; the 400-mg suspension was bioequivalent to a 400-mg capsule (laboratory batch). Thus we concluded that the capsule and the suspension dosage forms were bioequivalent.

Administration, Oral↗
PubMed1999

Comparative mucoretention of sucralfate suspensions in an everted rat esophagus model.

A simple, rapid, and reproducible in vitro model was established to quantify the relative esophageal mucoadhesive properties of viscous liquid formulations, and the model was applied to compare marketed sucralfate suspensions (Gastrogel, Antepsin, and Ulcogant) to better understand differences in clinical performance. Rat esophageal mucosal segments were everted onto a glass rod and briefly immersed into a liquid formulation containing 51Cr microspheres. Indirect quantification of the retained formulation provided excellent recovery (98.7-101%) and reasonable precision (1.06-38.3% CV). Mucosal retention profiles of the formulations were determined by rinsing the coated tissue in relevant gastrointestinal fluids using the technique of reciprocating vertical immersion. Dispersions of the mucoadhesive hydrogel Carbopol 934P were employed to initially characterize the performance of the model with respect to composition of the rinse fluids, and type and amount of shear force during rinsing. Retention of Carbopol was sensitive to the mechanics of rinsing and to salivary salts but not mucin in the rinse medium. A sucralfate gel suspension (Gastrogel) showed much greater mucoadhesion and resistance to removal by saliva than two non-gel suspensions (Antepsin, Ulcogant). Results suggest that in situ gelation may be a contributing mechanism for strong esophageal retention. These in vitro results are in general agreement with published human esophageal retention data on similar sucralfate suspensions and lend credence to the everted rat esophagus as a qualitatively predictive in vitro model for development of esophageal mucoadhesive liquids.

Adhesiveness↗
PubMed1998

Dose uniformity of ophthalmic suspensions.

PURPOSE: To quantify the rate of redispersion of three commercially available ophthalmic preparations as well as the drug content of single drops during the course of emptying a full container of suspension eyedrops. SETTING: Department of Ophthalmology, University of Köln, and Department of Pharmaceutical Technology, University of Bonn, Germany. METHODS: In a computer-controlled test apparatus used to simulate the shaking and dropping behavior of humans under strictly reproducible conditions, we studied the rate of redispersion of three ophthalmic suspensions: 50 mg indomethacin, 50 mg prednisolone-21-acetate, and 50 mg dexamethasone in 5 mL of aqueous fluid. The degree of shaking intensity essential for the redispersion of the ophthalmic suspensions was quantified in healthy persons and patients by an acceleration sensor. RESULTS: The mean dose delivered and the coefficient of variation of prednisolone were satisfactory. However, only 25% of the dexamethasone was available for administration; the rest remained in the bottle as a cake of sediment. Also, the variability of the drug content between drops was unacceptably high. The mean dose of indomethacin was adequate, but the between-drop variability was excessive. CONCLUSION: The dose uniformity of suspension eyedrops depends on their homogeneity immediately before administration. Among the formulation factors studied, particle size appears to be the most important. The various redispersion rates of the three drugs underline their clinical profile.

Administration, Topical↗
PubMed2006

[Production of gastrodin through biotransformation of p-hydroxybenzaldehyde by cell suspension cultures of Datura tatula L].

The conversion of exogenous p-hydroxybenzaldehyde to p-hydroxy-methyl-phenol-beta-D-glucoside (gastrodin) was studied by using cell suspension culture of Datura tatula L. The chemical structure of this synthesized gastrodin was identified based on the spectral analysis and chemical evidence. The conversion procedure of p-hydroxybenzaldehyde into gastrodin by D. tatula L. cell suspension cultures was established. The synthesized gastrodin (II) was isolated from the ferment liquor and identified by spectral analysis. At the same time, the p-hydroxybenzyl alcohol (I) converted through biotransformation of p-hydroxybenzaldehyde by cell suspension cultures of D. tatula L. was also isolated and identified. The efficiency of glucosylation of p-hydroxybenzaldehyde was remarkably enhanced by adding salicylic acid (0.1 mg/L) and keeping the lower pressure (0.001MPa) in 25L airlift loop bioreactor. The biotransformation of exogenous p-hydroxybenzaldehyde to gastrodin by cell suspension culture of D. tatula L. is a promising approach.

Benzaldehydes↗
PubMedDate not supplied

Enhanced human thrombopoietin production by sodium butyrate addition to serum-free suspension culture of bcl-2-overexpressing CHO cells.

When sodium butyrate (NaBu) was added to serum-free suspension culture of recombinant CHO (rCHO) cells for enhanced expression of human thrombopoietin (hTPO), apoptotic cell death of rCHO cells was induced in a dose-dependent manner and hTPO quality was deteriorated in regard to sialic acid and acidic isoform contents. To overcome these problems, we overexpressed Bcl-2 protein, an antiapoptotic protein, in rCHO cells producing hTPO. Compared to serum-free suspension culture of control cells without Bcl-2 overexpression (R-neo cells) and NaBu addition, a more than 10-fold increase in the maximum hTPO concentration was obtained in serum-free suspension culture of cells with Bcl-2 overexpression (R-bc12-14 cells) and 3 mM NaBu addition. Both the enhanced specific productivity endowed by NaBu and the extended culture longevity provided by the antiapoptotic effect of Bcl-2 overexpression contributed to the enhancement of maximum hTPO concentration. The problem of quality reduction of hTPO induced by NaBu was not solved by Bcl-2 overexpression, but it was not that significant. Compared to the culture in the absence of NaBu, the percentage of hTPO isoforms in pI 3-5 with high in vivo biological activity produced by R-bc12-14 cells was decreased by approximately 18% in the presence of 3 mM. As a result, a more than 6-fold increase in the production of hTPO isoforms in pI 3-5 was achieved in R-bcl2-14 cell culture with 3 mM NaBu addition. Taken together, the data obtained suggest that Bcl-2 overexpression in rCHO cells and NaBu addition in serum-free suspension culture can be an effective means to enhance the production of highly glycosylated protein such as hTPO.

Animals↗
PubMed1997

Formulation of a charcoal suspension for intratumor injection. Part 1: Study of the nature, granulometry, and concentration.

PURPOSE: We developed a charcoal suspension formulation to be injected intratumorally so that human breast cancers can be tatooed prior to chemotherapy. This deposit is intended to guide the surgeon at the time of the biopsy and resection, especially when the tumor nodule is not visible. The stain should remain in the tumor as long as the patient is on chemotherapy and should be harmless. METHODS: We studied on the effect on the nature of the charcoal, its granulometric profile, and its concentration. We then measured diffusion in vitro, in gel, and in vivo in experimental tumors. RESULTS: The formulation selected was prepared with a peal charcoal suspension in water for parenteral injections, with 50% of the particles measuring on average between 2 and 5 microns. The finest particles (< 2 microns) seem to produce the greatest in vitro diffusion and are more readily phagocyted by macrophages and thus eliminated from the tumor by those cells. CONCLUSIONS: This charcoal suspension has satisfactory formulation characteristics and diffuses the least, be it in vitro or in vivo, mainly due to the granulometric distribution of the suspension.

Animals↗
PubMed2004

Drug solubilization behavior during in vitro digestion of suspension formulations of poorly water-soluble drugs in triglyceride lipids.

PURPOSE: The purpose of this study was to characterize the solubilization and precipitation characteristics of a range of poorly water-soluble drugs during the in vitro digestion of long-chain or medium-chain triglyceride (TG) lipid suspension formulations. METHODS: TG suspensions of model drugs (present at double their equilibrium solubilities in the respective lipid) were digested in vitro and the drug solubilization and precipitation pattern in the resulting digests analyzed. RESULTS: For griseofulvin, diazepam, and danazol, solubilization of the small mass of drug originally presented in the TG lipid was efficient with only a small proportion of the dose precipitating and being recovered in the pellet phase after digestion of the TG lipid. For the more lipophilic and lipid-soluble drugs (cinnarizine, halofantrine), in which higher drug loadings were possible, significant enhancement in drug solubilization in the postdigestion aqueous phase was not apparent compared with simple TG lipid solutions. CONCLUSIONS: Suspensions of drugs, which are poorly soluble in water and TG lipid, may prove beneficial as the relatively high solubilizing capacity of the colloidal phases produced on TG digestion will likely exceed the mass of drug that could have been administered as a simple lipid solution. However, for more lipid-soluble drugs, suspension formulations may offer little benefit as sufficiently high drug loadings can otherwise be achieved with simple solution formulations that still provide for adequate solubilization after TG digestion.

Cinnarizine↗
PubMed2004

Characterization of suspension-based metered dose inhaler formulations composed of spray-dried budesonide microcrystals dispersed in HFA-134a.

PURPOSE: To assess the physicochemical characteristics and aerosol properties of suspensions of lipid-coated budesonide microcrystals dispersed in HFA-134a. METHODS: Lipid-coated budesonide microcrystals were prepared by spray-drying an emulsion-based feedstock. Physicochemical characteristics of spray-dried particles were assessed by electron microscopy, laser diffraction, and differential scanning calorimetry. Purity and content were determined by reverse-phase HPLC. Particle aggregation and suspension stability were assessed visually, and aerosol performance was assessed by Andersen cascade impaction and dose content uniformity. RESULTS: Spray-drying of micronized budesonide microcrystals in the presence of phospholipid-coated emulsion droplets results in the production of low-density lipid-coated microcrystals with low surface energy. These spray-dried particles form stable suspensions in HFA-134a. This translates into good uniformity in the metered dose across the contents of the inhaler and acceptable aerodynamic particle size distributions (MMAD = 3.2 to 3.4 microm). The formulation was observed to maintain its performance over 6 months at 40 degrees C/75% RH and 16 months at 25 degrees C/60% RH. No effect of storage orientation was observed on the content of first sprays following storage (i.e., no Cyr effect). The fine particle dose was found to be linear out to suspension concentrations of about 2% wt/vol, and FPD(4.7 microm) values approaching 400 microg can be delivered in a single inhalation. CONCLUSIONS: Engineered particles comprised of lipid-coated microcrystals may provide an acceptable alternative formulation technology for metered dose inhalers in the new hydrofluoroalkane propellants.

Aerosol Propellants↗
PubMed2000

Changes in capillary luminal diameter in rat soleus muscle after hind-limb suspension.

This study examined the time course change of the capillary luminal diameter and the number of capillaries in the rat soleus muscle during hind-limb suspension. Male Wistar rats were divided into 1 and 3 weeks of hind-limb suspension (HS) groups (HS-1 and HS-3). The HS groups were compared with age-matched control groups. All morphometric parameters with respect to capillary and muscle fibre cross-sectional area were determined in perfusion-fixed soleus muscles. After 1 and 3 weeks of hind-limb suspension, the mean muscle fibre cross-sectional area was significantly decreased in HS-1 (-32.0%) and HS-3 (-59.3%) compared with age-matched control groups. Despite a lower capillary-to-fibre ratio (HS-1, -19.3%; HS-3, -21.2%), the capillary density was unchanged in HS-1 and significantly increased in HS-3 compared with age-matched control groups. The mean capillary luminal diameter was significantly smaller in HS-1 (-19.9%) and HS-3 (-21.9%) than in the age-matched control groups. The capillary-to-fibre perimeter ratio which indicates the capillary surface area available for gas exchange between blood and tissue did not significantly differ between control groups and HS groups. In conclusion, the morphometrical adaptations in rat soleus with the suspension involved changes in both the capillary luminal diameter and number of capillaries, and the change in capillary surface area was proportional to the degree of muscle atrophy in HS groups.

Adaptation, Physiological↗
PubMed2004

Studies on the bioequivalence of second generation cephalosporins: cefaclor capsules and suspension.

The aim of the present studies, performed in two different groups of volunteers, was to prove the bioequivalence of 500 mg cefaclor (CAS 70356-03-5) test and reference capsules (Losefar 500 mg Capsules as test and an originator product as reference; study 1) and cefaclor 250 mg/5 mL test and reference suspensions (Losefar 250 mg/5 mL Granules oral suspension as test and an originator product as reference; study 2). Each study was conducted according to an open, randomized, single-dose, two-period cross-over design in healthy volunteers with a wash-out period from 7 to 14 days. Blood samples were taken up to 8 h post dosing, and concentrations of cefaclor were determined by HPLC method. In the first study, the 90% confidence intervals for intra-individual ratios of AUC0-t and Cmax of cefaclor were 0.99-1.08 for AUC0-t and 0.82-1.06 for Cmax, and thus within the acceptance ranges for bioequivalence trials. The 90% confidence interval for intra-individual ratios of AUC0-t and Cmax of cefaclor administered as suspensions were 1.10-1.19 and 1.02-1.21, respectively. These values were also within the acceptance range. Concerning the secondary parameter tmax the 90% confidence interval for the intra-individual differences for cefaclor were between -0.13 - 0.13 in the first and between 0.00 - 0.13 in the second study, respectively. In the light of the results of the studies reported here it can be concluded that cefaclor test formulations, i.e. capsules and suspension are bioequivalent to the respective reference formulations.

Adolescent↗
PubMed1999

Formulation of a charcoal suspension for intratumoral injection. Study of galenical excipients.

To tattoo human breast cancer prior to chemotherapy, radiotherapy, or surgery, thus allowing a better localization of the remaining tumor by the surgeon, we developed a formulation containing 10% charcoal suspended in water for parenteral preparations. The present study concerns a new step in the development of the charcoal suspension. We sought to determine whether the addition of various excipients could improve the formulation properties and affect the labeling of tumor by the suspension. We have tested surfactants (egg lecithin, polysorbate 80, Cremophor EL, and Pluronic F68), isotonisants (sugars such as glucose and mannitol), polysaccharides (dextrans 20 and 40), and Cabosil, a pyrogenated silica. Except for glucose and mannitol, which were added at a 5% concentration, the other excipients were added at a 0.1% concentration, they were dissolved in water for parenteral injection and sterilized at 120 degrees C for 20 min. We then measured diffusion in vivo in mammary tumor. In vivo, when injected intratumorally in mice, a greater diffusion of charcoal particles was noted within the tumor (in the case of egg lecithin, polysorbate 80, dextran 20 and 40, and glucose) and sometimes in some organs (e.g., Cremophor EL and mannitol). Pluronic F68 slightly improved the stability of the suspension and did not lead to marked diffusion at the injection site, but it showed slight toxicity and cannot be used in the formulation. We concluded that the best formulation was an aqueous 10% micronized peat charcoal suspension.

Adenocarcinoma↗
PubMed1956

Studies on the transfer of lymph node cells. VII. Transfer of cells incubated in vitro with filtrates of trypsin-treated suspensions of Shigella paradysenteriae.

Shigella paradysenteriae organisms were incubated in a solution of trypsin and then removed from the suspension by Seitz filtration. Serologic tests with anti whole Shigella serum indicated that the filtrate contained antigenic material derived from the organisms. When lymph node cells from rabbits not previously injected with Shigella were incubated in vitro with such filtrates and then transferred to irradiated recipients, agglutinins to Shigella appeared in the sera of the latter. The transfer of heated suspensions of cells was not followed by the appearance of agglutinins in irradiated recipient rabbits. Non-irradiated recipients of lymph node cells incubated with the filtrate also developed agglutinin titers, to a lower level than irradiated animals. Agglutinins did not appear in the sera of the majority of non-irradiated recipients of heated cells. The addition of excess antiserum to either the filtrate or the cell suspension before the incubation of these two materials resulted in a marked reduction in the subsequent agglutinin titers of recipient animals. However, if antiserum was added at the conclusion of the usual 30 minute incubation of cells and filtrate, or even after 5 minutes of incubation, there was no reduction in the agglutinin titers of the recipients. Cytologic examination of aliquots of a number of the suspensions of cells prepared for transfer revealed that approximately 98 to 99 per cent of the cells belonged to the lymphocytic series.

Animals↗